20030147 Ver 2_Dissolved Oxygen Rpt_20120120

Mr Ian McMillian
N C Division of Water Quality
401 Oversight/Express Review Permitting Unit
1650 Mail Service Center
Raleigh NC 27699 1650
Dear Mr McMillian
03- o�4 -7 Ua-
January 20 2012
1
DO
JAN 2 0 2012
DENR WATER QUALITY
Wands & &ormwauv Rrnnrl�
SUBJECT Submittal of Tillery and Blewett Falls Dissolved Oxygen Enhancement Reports
Progress Energy Carolinas Inc — Yadkin Pee Dee Hydroelectric Project No 2206
Please find enclosed three reports pertaining to Progress Energy Carolinas Inc s Dissolved
Oxygen (DO) Enhancement Plan for the Yadkin Pee Dee Hydroelectric Project Tillery and
Blewett Falls hydroelectric developments (FERC Project No 2206) These studies were
conducted as part of Progress Energy s DO Enhancement Plan to achieve water quality standards
for dissolved oxygen by the end of 2011 per 401 Water Quality Certificate (WQC) requirements
(401 WQC No 3730 modl issued by the N C Division of Water Quality on September 12,
2008) These reports have been submitted to the Federal Energy Regulatory Commission
The first report summarizes the DO verification trials conducted in 2011 at the Tillery
Hydroelectric Plant These trials evaluated the installed reservoir oxygen diffuser system turbine
venting aeration and minimum flows releases on DO levels in the Tillery tailwaters
The second report summarizes the continuous DO and temperature monitoring conducted in the
Pee Dee River tailwaters below each power plant during 2010 Continuous monitoring reports
for the period of 2004 to 2009 have been previously filed with the NC DWQ and Federal Energy
Regulatory Commission
The third report is the DO Compliance Implementation Plan which specifies the technological
and operation measures that Progress Energy will undertake to comply with the North Carolina
DO Water Quality Standards This report also contains the compliance monitoring and reporting
measures as outlined in the 401 WQC issued by the NC DWQ Filing of this DO Enhancement
Plan fulfils the schedule set forth by Progress Energy in its 401 WQC application filed with the
NC DWQ on May 11 2007 and as specified in the 401 WQC issued by the NC DWQ on
September 12 2008
Progress Energy will be implementing the DO enhancement measures at each power plant this
year We will keep the NC DWQ staff informed of our efforts as we proceed with implementing
the DO Enhancement Plan
Progress Energy Carolinas Inc
Tillery Hydra Plant
179 Tillery Dam Road
Mount Gilead NC 27306

If you have questions regarding the 2011 reports or the DO Enhancement Plan please call me at
910 439 5211 Ext 1200 or John Crutchfield at 919 546 2019
Sincerely
enne
Manager Hydro Operations
Enclosures
c w/ enclosures Mr John Crutchfield
Mr Mike Lawyer —N C Division of Water Quality
Mr Larry Mann

Ms Kimberly Bose Secretary
Federal Energy Regulatory Commission
Mail Code DPCA, HL 21 1
888 First Street NE
Washington DC 20426
Dear Secretary Bose
January 20 2012
L�
JAN202012
DENR W4
etla
nd St. .. ! QVAi ,,
SUBJECT Submittal of Tillery and Blewett Falls Dissolved Oxygen Enhancement Reports
Progress Energy Carolinas Inc — Yadkin Pee Dee Hydroelectric Project No 2206
Please find enclosed three reports pertaining to Progress Energy Carolinas Inc s Dissolved
Oxygen (DO) Enhancement Plan for the Yadkin Pee Dee Hydroelectric Protect Tillery and
Blewett Falls hydroelectric developments (FERC Project No 2206) These studies were
conducted as part of Progress Energy s DO Enhancement Plan to achieve water quality standards
for dissolved oxygen by the end of 2011 per 401 Water Quality Certificate (WQC) requirements
(401 WQC No 3730 mod] issued by the N C Division of Water Quality on September 12
2008) These reports have been submitted to the N C Division of Water Quality (NC DWQ)
The first report summarizes the DO verification trials conducted in 2011 at the Tillery
Hydroelectric Plant These trials evaluated the installed reservoir oxygen diffuser system turbine
venting aeration and minimum flows releases on DO levels in the Tillery tailwaters
The second report summarizes the continuous DO and temperature monitoring conducted in the
Pee Dee River tailwaters below each power plant during 2010 Continuous monitoring reports
for the period of 2004 to 2009 have been previously filed with the NC DWQ and Federal Energy
Regulatory Commission
The third report is the DO Compliance Implementation Plan which specifies the technological
and operation measures that Progress Energy will undertake to comply with the North Carolina
DO Water Quality Standards This report also contains the compliance monitoring and reporting
measures as outlined in the 401 WQC issued by the NC DW Q Filing of this DO Enhancement
Plan fulfils the schedule set forth by Progress Energy in its 401 WQC application filed with the
NC DWQ on May 11 2007 and as specified in the 401 WQC issued by the NC DWQ on
September 12 2008
Progress Energy will be implementing the DO enhancement measures at each power plant this
year We will keep the FERC staff informed of our efforts as we proceed with implementing the
DO Enhancement Plan
Progress Energy Carolinas Inc
T lir i D Plat t
179 id parr rt i
t luu it lead NC 1o1E

If you have questions regarding the 2011 reports or the DO Enhancement Plan please call me at
910 439 5211 Ext 1200 or John Crutchfield at 919 546 -2019
Sincerely
len enne
Manager Hydro Operations
Enclosures
c w/ enclosures Mr John Crutchfield
Mr Larry Mann
c w/o enclosures Mr Ian McMillian —N C Division of Water Quality

Yadkin -Pee Dee River Hydroelectric Project
FERC No. 2206
Continuous Water Quality Monitoring in the
Pee Dee River below the Tillery and Blewett
Falls Hydroelectric Plants,
May- October, 2010
p"
January 2012
&4�' Progress Energy

TABLE OF CONTENTS
Section Title Page No.
LISTOF FIGURES ............................................ ............................... ............................III
LISTOF TABLES ......................................................................... ............................... VI
ACRONYMLIST ..................................................................... ............................... AL- I
EXECUTIVE SUMMARY .............................................................. ............................ES- I
SECTION 1 - INTRODUCTION ..................................................... ............................... 1 -1
SECTION 2 - STUDY OBJECTIVES .............................................. ............................... 2 -1
SECTION 3 - SITE DESCRIPTION ................................................ ............................... 3 -1
3.1 Reach 1 - Pee Dee River Below the Tillery Development ............... ............................... 3 -1
3.2 Reach 2 - Pee Dee River Below the Blewett Falls Development ..... ............................... 3 -1
SECTION4 - METHODS ............................................................. ............................... 4 -1
4.1
Continuous Monitor Locations .........................................................
............................... 4 -1
4.2
Continuous Monitor Deployment .....................................................
............................... 4 -2
4.3
Continuous Monitor Service and Calibration ...................................
............................... 4 -3
4.4
Data Validation and Review .............................................................
............................... 4 -3
4.5
Quality Assurance and Quality Control ............................................
............................... 4 -3
RESULTS AND DISCUSSION
SECTION 5 - ENVIRONMENTAL AND RESERVOIR CONDITIONS .. ............................... 5 -1
5.1
Environmental Conditions ................................................................
............................... 5 -1
5.1.1
Climatological Conditions ................................................................
............................... 5 -1
5.1.2
River Flow Conditions ......................................................................
............................... 5 -2
5.2
Dissolved Oxygen in Project Reservoirs ..........................................
............................... 5 -5
5.2.1
Lake Tillery .......................................................................................
............................... 5 -5
5.2.2
Blewett Falls Lake ............................................................................
............................... 5 -6
I

TABLE OF CONTENTS
(Continued)
Section Title Page No.
SECTION 6 - 2010 WATER QUALITY RESULTS .......................... ............................... 6 -1
6.1
Water Quality in the Pee Dee River, 2010 ........................................ ...............................
6 -1
6.1.1
Dissolved Oxygen — Tillery Dam to Turkey Top Creek (Reach 1) .. ...............................
6 -1
6.1.2
North Carolina Water Quality Standards for DO in Reach 1 ........... ...............................
6 -7
6.1.3
Operational Effects of the Tillery Hydroelectric Plant ..................... ...............................
6 -9
6.1.4
Dissolved Oxygen — Blewett Falls Dam to Below Hitchcock Creek (Reach 2) ............
6 -12
6.1.5
North Carolina Water Quality Standards for DO in Reach 2 ......... ...............................
6 -16
6.1.6
Operational Effects of the Blewett Falls Hydroelectric Plant ......... ...............................
6 -18
6.1.7
Comparison of Dissolved Oxygen Temporal Trends, 2004 -2010 .. ...............................
6 -19
6.2
Water Temperature in the Pee Dee River ....................................... ...............................
6 -23
6.2.1
Reach 1 — Tillery Dam to Turkey Top Creek ................................. ...............................
6 -23
6.2.2
Reach 2 — Blewett Falls Dam to Below Hitchcock Creek .............. ...............................
6 -24
6.3
pH in the Pee Dee River .................................................................. ...............................
6 -26
6.3.1
Reach 1 — Tillery Dam to Turkey Top Creek ................................. ...............................
6 -26
6.3.2
Reach 2 — Blewett Falls Dam to Below Hitchcock Creek .............. ...............................
6 -28
6.4
Specific Conductance in the Pee Dee River ................................... ...............................
6 -29
6.4.1
Reach 1 — Tillery Dam to Turkey Top Creek ................................. ...............................
6 -29
6.4.2
Reach 2 — Blewett Falls Dam to Below Hitchcock Creek .............. ...............................
6 -30
SECTION7 - SUMMARY ............................................................ ............................... 7 -1
SECTION 8 - REFERENCES ......................................................... ............................... 8 -1
APPENDICES
APPENDIX A SUMMARY OF CONTINUOUS MONITOR PERFORMANCE IN REACHES 1
AND 2 OF THE PEE DEE RIVER BELOW THE TILLERY AND BLEWETT
FALLS HYDROELECTRIC PLANTS, 2010.
II

LIST OF FIGURES
Section Title Page No.
3 -1 Map of the Tillery Development and Reach 1 of the Pee Dee River showing
continuous water quality monitoring stations ....................... ............................... 3 -2
3 -2 Map of the Blewett Falls Development and Reach 2 of the Pee Dee River
showing continuous water quality monitoring stations ........ ............................... 3 -3
5 -1 Comparison of monthly precipitation totals during the 2010 period
to the 72 -year monthly minimum, maximum and mean precipitation totals
for the period 1938 to 2010 ................................................... ............................... 5 -1
5 -2 Comparison of mean monthly air temperatures during the 2010
period with the 72 -year monthly minimum, maximum and mean air
temperatures for the period 1938 to 2010 ............................. ............................... 5 -2
5 -3 Daily mean stream flow for the Rocky River at the N.C. Highway 52 Bridge
and the Pee Dee River at the U.S. Highway 74 Bridge, 2010 ............................. 5 -3
5 -4 Plant discharge at the Tillery Hydroelectric Plant, May- October 2010 ............... 5 -4
5 -5 Plant discharge at the Blewett Falls Hydroelectric Plant, May- October
2010 ....................................................................................... ............................... 5 -4
5 -6 Vertical profiles of dissolved oxygen concentrations measured at Station B2
at Lake Tillery, May through November, 2010 .................... ............................... 5 -5
5 -7 Vertical profiles of dissolved oxygen concentrations measured at Station B2
at Blewett Falls Lake, May through November, 2010 .......... ............................... 5 -6
6 -1 Weekly mean dissolved oxygen concentrations at continuous monitor
stations in Reach 1 of the Pee Dee River below the Tillery Hydroelectric
Plant, May 1 to October 31, 2010 ......................................... ............................... 6 -2
6 -2 Daily averages and ranges of dissolved oxygen concentrations at Stations
TYCM1 -1, TYCM1 -2, TYCM1 -3 and TYCM2 in Reach 1 of the Pee Dee
River below the Tillery Hydroelectric Plant, May 1 to November 30, 2010....... 6 -3
6 -3 Frequency distributions of dissolved oxygen concentrations at continuous
monitor stations in Reach 1 of the Pee Dee River below the Tillery
Hydroelectric Plant, May 1 to October 31, 2010 .................. ............................... 6 -5
6 -4 Dissolved oxygen concentrations and power plant generation flows in Reach
1 of the Pee Dee River below the Tillery Hydroelectric Plant, July 18 to July
22, 2010 ................................................................................. ............................... 6 -6
III

LIST OF FIGURES
(Continued)
Figure Title Page No.
6 -5 Dissolved oxygen concentrations on July 3 with no power plant geration
flow at Stations TYCM1 -1, TYCM1 -2 and TYCM2 ......... ............................... 6 -10
6 -6 Dissolved oxygen concentrations and power plant generation flow from
July 6 to July 12 at Stations TYCM 1 -1, TYCM 1 -2, TYM 1 -3
andTYCM2 ....................................................................... ............................... 6 -11
6 -7 Weekly mean dissolved oxygen concentrations at continuous monitor
stations in Reach 2 of the Pee Dee River below the Blewett Falls
Hydroelectric Plant, May 1 to October 31, 2010 ................ ............................... 6 -14
6 -8 Frequency distributions of dissolved oxygen concentrations at continuous
monitor stations in Reach 2 of the Pee Dee River below the Blewett Falls
Hydroelectric Plant, May 1 to October 31, 2010 ................ ............................... 6 -15
6 -9 Daily averages and ranges of dissolved oxygen concentrations at Stations
BFCM1, BFCMIA, and BFCM2A in Reach 2 of the Pee Dee River below
the Blewett Falls Hydroelectric Plant, May 1 to November 30, 2010 ............... 6 -17
6 -10 Dissolved oxygen concentrations at Stations BFCM1, BFCMIA and
BFCM2A, and power plant gernations flows at the Blewett Falls
Hydroelectric Plant July 6 to July 12, 2010 ........................ ............................... 6 -19
6 -11 Weekly mean temperatures at continuous monitor stations in Reach 1
of the Pee Dee River below the Tillery Hydroelectric Plant, May 1 to
October31, 2010 ................................................................. ............................... 6 -24
6 -12 Weekly mean temperatures at continuous monitor stations in Reach 2
of the Pee Dee River below the Blewett Falls Hydroelectric Plant,
May 1 to October 31, 2010 ................................................. ............................... 6 -25
6 -13 Weekly mean pH values at continuous monitor stations in Reach 1
of the Pee Dee River below the Tillery Hydroelectric Plant, May 1 to
October31, 2010 ................................................................. ............................... 6 -26
6 -14 Dissolved oxygen concentrations and pH values at Station TYCM2 in
Reach 1 of the Pee Dee River below the Tillery Hydroelectric Plant,
May6 to 14, 2010 ............................................................... ............................... 6 -27
6 -15 Weekly mean pH values at continuous monitor stations in Reach 2
of the Pee Dee River below the Blewett Falls Hydroelectric Plant,
May 1 to October 31, 2010 ................................................. ............................... 6 -28
IV

LIST OF FIGURES
(Continued)
Figure Title Page No.
6 -16 Weekly mean specific conductance values at continuous monitor stations
in Reach 1 of the Pee Dee River below the Tillery Hydroelectric Plant,
May 1 to October 31, 2010 ................................................. ............................... 6 -29
6 -17 Weekly mean specific conductance values at continuous monitor stations
in Reach 2 of the Pee Dee River below the Blewett Falls Hydroelectric
Plant, May 1 to October 31, 2010 ....................................... ............................... 6 -30
V

LIST OF TABLES
Table Title Page No.
4 -1 Description of station locations used in the continuous water quality study
in Reaches 1 and 2 of the Pee Dee River below the Tillery and Blewett
Falls Hydroelectric Plants, 2010 ........................................... ............................... 4 -1
4 -2 Locations, GPS coordinates, water depths, and types of deployment for seven
continuous water quality monitor stations in Reaches 1 and 2 of the Pee
Dee River below the Tillery and Blewett Falls Developments ............................ 4 -2
6 -1 Dissolved oxygen concentration summary for Reach 1 of the Pee Dee River
below the Tillery Hydroelectric Plant, May 1 to October 31, 2010 .................... 6 -1
6 -2 Assessments of daily dissolved oxygen concentrations from May 1 to
October 31, 2010 at stations in Reach 1 of the Pee Dee River below the
Tillery Hydroelectric Plant compared to the North Carolina dissolved
oxygen water quality standards ............................................. ............................... 6 -8
6 -3 Days that no power was generated at the Tillery Hydroelectric Plant and
assessments of dissolved oxygen concentrations at stations in Reach 1 to
determine if they met the North Carolina water quality standards for daily
average and instantaneous dissolved oxygen concentrations during 2010........ 6 -12
6 -4 Dissolved oxygen concentration summary for Reach 2 of the Pee Dee River
below the Blewett Falls Hydroelectric Plant, May 1 to October 31, 2010 ........ 6 -13
6 -5 Assessments of daily dissolved oxygen concentrations from May 1 to
October 31, 2010 at stations in Reach 2 of the Pee Dee River below the
Blewett Falls Hydroelectric Plant compared to the North Carolina DO
waterquality standards ....................................................... ............................... 6 -16
6 -6 Comparison of DO summary statistics between the 2004 to 2010 continuous
monitoring programs for the Tillery and Blewett Falls Hydroelectric
Plants................................................................................... ............................... 6 -20
6 -7 Summary statistics of water quality variables from stations in Reach 1
of the Pee Dee River below the Tillery Hydroelectric Plant,
May 1 to October 31, 2010 ................................................ ............................... 6 -23
6 -8 Summary statistics of water quality variables from stations in Reach 2 of the
Pee Dee River below the Blewett Falls Hydroelectric Plant,
May 1 to October 31, 2010 ................................................. ............................... 6 -25
V1

Acronym List
Federal /State Agencies
Advisory Council on Historic Preservation (ACHP)
Federal Aviation Administration (FAA)
Federal Energy Regulatory Commission (FERC)
National Park Service (NPS)
National Marine Fisheries Service (NMFS)
National Oceanic and Atmospheric Administration (NOAA)
National Resource Conservation Service (NRCS) formerly known as Soil Conservation Service
National Weather Service (NWS)
North Carolina Department of Environment and Natural Resources (NCDENR)
North Carolina Environmental Management Commission (NCEMC)
North Carolina Department of Natural and Economic Resources, Division of Environmental
Management (NCDEM)
North Carolina Division of Parks and Recreation (NCDPR)
North Carolina Division of Water Resources (NCDWR)
North Carolina Division of Water Quality (NCDWQ)
North Carolina Natural Heritage Program (NCNHP)
North Carolina State Historic Preservation Officer (NCSHPO)
North Carolina Wildlife Resources Commission (NCWRC)
South Carolina Department of Natural Resources (SCDNR)
South Carolina Department of Health and Environmental Control (SCDHEC)
State Historic Preservation Office (SHPO)
U.S. Army Corps of Engineers (ACOE)
U.S. Department of Interior (DOI)
U.S. Environmental Protection Agency (USEPA)
U.S. Fish and Wildlife Service (USFWS)
U.S. Geological Survey (USGS)
U.S. Department of Agriculture (USDA)
U.S. Forest Service (USFS)
Other Entities
Alcoa Power Generating, Inc., Yadkin Division (APGI)
Progress Energy (Progress)
University of North Carolina at Chapel Hill (UNCCH)
Facilities/Places
Yadkin - Pee Dee River Project (entire two - development project including both powerhouses,
dams and impoundments)
Blewett Falls Development (when referring to dam, powerhouse and impoundment)
Blewett Falls Dam (when referring to the structure)
Blewett Falls Hydroelectric Plant (when referring to the powerhouse)
Blewett Falls Lake (when referring to the impoundment)
Tillery Development (when referring to dam, powerhouse and impoundment)
Tillery Dam (when referring to the structure)
Tillery Hydroelectric Plant (when referring to the powerhouse)
Lake Tillery (when referring to the impoundment)
A1, -1

Acronym List
Acronym List
(Continued)
Documents
401 Water Quality Certification (401 WQC)
Draft Environmental Assessment (DEA)
Environmental Assessment (EA)
Environmental Impact Statement (EIS)
Final Environmental Assessment (FEA)
Initial Consultation Document (ICD)
Memorandum of Agreement (MOA)
National Wetland Inventory (NWI)
Notice of Intent (NOI)
Notice of Proposed Rulemaking (NOPR)
Preliminary Draft Environmental Assessment (PDEA)
Programmatic Agreement (PA)
Scoping Document (SD)
Shoreline Management Plan (SMP)
Laws/Regulations
Clean Water Act (CWA)
Code of Federal Regulations (CFR)
Electric Consumers Protection Act (ECPA)
Endangered Species Act (ESA)
Federal Power Act (FPA)
Fish and Wildlife Coordination Act (FWCA)
National Environmental Policy Act (NEPA)
National Historic Preservation Act (NHPA)
Terminology
Alternative Relicensing Process (ALP)
Cubic feet per second (cfs)
Degrees Celsius ( °C)
Degrees Fahrenheit ( °F)
Dissolved oxygen (DO)
Feet (ft)
Gallons per day (gpd)
Geographic Information Systems (GIS)
Gigawatt Hour (GWh)
Global Positioning System (GPS)
Grams (g)
Horsepower (hp)
Kilogram (kg)
Kilowatts (kW)
Kilowatt -hours (kWh)
Mean Sea Level (msl)
Megawatt (MW)
AL -2

Acronym List
Acronym List
(Continued)
Terminology
Megawatt -hours (MWh)
Meter (m)
Micrograms per liter (µg/L)
Milligrams per liter (mg/L)
Millimeter (mm)
Million gallons per day (mgd)
National Geodetic Vertical Datum (NGVD)
National Wetlands Inventory (NWI)
Non - governmental Organizations (NGOs)
Ounces (oz.)
Outstanding Remarkable Value (ORV)
Parts per billion (ppb)
Parts per million (ppm)
Pounds (lbs.)
Power Factor (p.f.)
Probable Maximum Flood (PMF)
Project Inflow Design Flood (IDF)
Rare, Threatened, and Endangered Species (RTE)
Ready for Environmental Assessment (REA)
Resource Work Groups (RWG)
Revolutions per Minute (rpm)
Rights -of -Way (ROW)
Stakeholders (federal and state resource agencies, NGOs, and other interested parties)
Volts (V)
AL -3

Executive Summary
This monitoring program assessed the spatial and temporal patterns of dissolved oxygen (DO)
concentrations in the Pee Dee River downstream of the Tillery and Blewett Falls hydroelectric
plants using in -situ continuous monitoring instruments during May through October, 2010. The
2010 monitoring program methods were essentially the same as the programs conducted during
2004 -2009, as part of the environmental relicensing studies.
The 2010 monitoring program evaluated the longitudinal (upstream to downstream) differences
in DO concentrations in the Pee Dee River below both power plants, and the latitudinal (east
bank to west bank) differences (2008 -2010) immediately below the Tillery Plant. Monitoring
was conducted from May- October to capture the seasonal period of hypolimnetic stratification in
both project reservoirs. The study also evaluated spatial and temporal patterns of temperature,
pH, and specific conductance below each power plant.
Four continuous water quality monitors were placed in Reach 1 and three continuous water
quality monitors were placed in Reach 2 within sections presently or previously designated by
the NCDWQ as impaired for DO under Section 303(d) of the Clean Water Act. The NCDWQ
listed the 4.9 mile reach from the Tillery Dam to the Rocky River confluence as impaired for DO
( NCDWQ 2010). These low DO concentrations occur seasonally during the warmer months
when the Project reservoirs stratify and the deeper reservoir waters have low DO concentrations.
Measured DO concentrations in the Pee Dee River from the Tillery Plant to the Rocky River
confluence were below the North Carolina DO water quality standards for instantaneous (4.0
mg/L) and daily average (5.0 mg/L) DO concentrations on some days from May through early
October of each monitored year. These periods corresponded with low DO levels in the deeper
water of Lake Tillery and the low DO concentrations in this water periodically released from the
Tillery Plant. Dissolved oxygen concentrations increased in the river below the Tillery Plant
after DO de- stratification in Lake Tillery during October. Dissolved oxygen concentrations were
also below one or both North Carolina water quality standards on days that the power plant did
not generate power. Dissolved oxygen concentrations immediately below the Tillery Plant were
more often below one or both water quality standards on non -power generation days than at
other downstream stations.
Dissolved oxygen concentrations in the river generally increased with increased distance from
the Tillery Plant due to re- aeration in the river channel and tributary inflow. Dissolved oxygen
concentrations were affected by natural diel cycles of algal photosynthesis and respiration as
well as power plant operations. Dissolved oxygen concentrations usually increased during
daylight hours and decreased at night as a result of algal photosynthesis and respiration. Tillery
Plant operations were most noticeable when power generation occurred after DO concentrations
began to rise during the morning hours. Dissolved oxygen concentrations in the river would
decrease when hypolimnetic water with low DO concentrations was released from Lake Tillery.
This change in DO concentrations was most evident 0.2 miles downstream of the Tillery Plant.
Similar to observations in previous years, there was a general increase in DO concentrations
from the east bank to the west bank at the water quality monitoring locations nearest the Tillery
Plant.
ES -1

Executive Summary
The period that DO concentrations did not meet the water quality standards occurred for a longer
period during 2010 in Reach 1 (i.e., early May through mid October) compared to the period
documented in other monitored years (i.e., mid May through early October [2004- 2009]). This
temporal difference was attributable to climatological differences, reservoir stratification
patterns, and frequency of plant generation. The year 2010 was marked by a warm, dry spring
and summer. However, in all years, reservoir de- stratification and DO levels above the state
water quality standards occurred by early to late September to mid October depending upon the
annual climatological conditions, reservoir inflow, and station location. Spatial trends in DO
concentrations in both river reaches were similar during all monitored years.
Dissolved oxygen concentrations did not consistently increase throughout Reach 2 with
increased distance from the Blewett Falls Plant. Both North Carolina water quality standards
were met more often at Station BFCM1, the uppermost monitoring station, than at any other
Station within Reach 2. The number of days not meeting the water quality standards for DO
concentrations (93, 67 and 70 days from 2008 -2010 respectively) and the percentage of DO
concentrations less than 5.0 mg/L (48.2 %, 34.5% and 31.3% from 2008 -2010, respectively) were
the greatest at Station BFCM2A, located approximately 2.1 miles downstream of the power
plant.
ES -2

Section I — Introduction
Progress Energy is currently relicensing the Tillery and Blewett Falls Developments (i.e.,
Yadkin -Pee Dee River Hydroelectric Project No. 2206) with the Federal Energy Regulatory
Commission (FERC). As part of the relicensing process, Progress Energy established Resource
Work Groups during May 2003 to identify environmental issues associated with Project
operations and develop study plans specific to Project lands and associated lakes and tailwaters.
The Water Resources Work Group (RWG) identified the need for additional water quality
studies of the Project reservoirs and tailwaters (i.e., Progress Energy 2004, Water RWG Issue
Nos. 7 and 8, "Lake Tillery and Blewett Falls Lakes and Tailwaters Water Quality "). The
purpose of these studies was to evaluate the water quality in the Project reservoirs and the Pee
Dee River below the Tillery and Blewett Falls Hydroelectric Plants. Specifically, these water
quality studies addressed: (1) meeting state water quality standards and supporting designated
uses in the reservoirs and tailwaters; (2) evaluating the Project operation effects on the water
quality in both reservoirs and downstream tailwaters; (3) cumulative effects of nutrient and
sediment loading on reservoirs and tailwaters; and (4) water quality effects of Rocky River
inflow.
Three studies were conducted during 2004 to address the water quality issues: (1) a monthly
sampling program at the Tillery and Blewett Falls Developments to characterize the existing
water quality conditions in the Project reservoirs and downstream tailwaters, including the
effects of the Rocky River tributary inflow (Progress Energy 2006a); (2) an intensive assessment
of the spatial and temporal patterns of temperature and DO concentrations in the Pee Dee River
downstream of each power plant (Progress Energy 2005a); and (3) a continuous monitoring
study of DO (Progress Energy 2005b) from May through November in the upper, mid and lower
reaches of the 303(d) impaired river reaches below each hydroelectric dam, as designated by the
NCDWQ (2006). These studies also characterized the water quality of the Project tailwaters
with and without power plant generation.
Progress Energy filed the results of the 2004 water quality studies in its Final License
Application (FLA) with FERC during April 2006 (Progress Energy 2006b).
In May 2007, Progress Energy submitted an application to the NCDWQ for a 401 Water Quality
Certificate (WQC) for the Project (Progress Energy 2007a). The WQC application also
contained the DO Enhancement Plan and schedule for meeting water quality standards at each
power plant. The NCDWQ issued the 401 WQC for the project during February 2008, which
was modified and subsequently reissued during September 2008 ( NCDWQ 2008a). The 401
WQC specified the timeline for compliance for meeting the state water quality standards at the
Project by the end of 2011.
To meet the state water quality standards, Progress Energy began an evaluation program to
assess various DO enhancement technologies, which began in the summer of 2005 and continued
through 2010. The goal of this evaluation program was to determine the least cost and most
technologically suitable method for each power plant to meet the state water quality standards.
Turbine draft tube venting has been implemented for the Blewett Falls Plant. A reservoir oxygen
diffuser system and supplemental draft tube venting has been implemented for the Tillery Plant.
1 -1

Section 1 Introduction
As part of the filed DO Enhancement Plan, Progress Energy also proposed to continue the
continuous monitoring of DO and temperature through 2010, on an interim basis, until
permanent temperature and DO compliance monitoring locations could be established at each
development. The continuous monitoring program (2010) followed the same methods used in
the 2004 relicensing study and a voluntary 2005 -2009 monitoring program (Progress Energy
2005b, 2006c, 2010).
This report provides the interim continuous water quality monitoring results in the river reaches
below the Tillery and Blewett Falls Hydroelectric Plants from May 1 to October 31, 2010. This
report marks the seventh year of monitoring (2004- 2010).
The NCDWQ has previously listed sections of the Pee Dee River below each hydroelectric plant
as impaired for aquatic life due to low DO concentrations from the hydropower operations
(NCDWQ 2006). Currently, the 4.9 -mile section of the Pee Dee River from Tillery Dam to the
confluence of the Rocky River is listed as impaired due to low DO concentrations
(NCDWQ 2010). The Blewett Falls section was removed from the 303(d) list by the NCDWQ
during 2010 (NCDWQ 2010). The Pee Dee River from Tillery Dam to Blewett Falls Lake has a
Class WS -IV,B, WS -V,B and WS- IV,B &CA water quality classification and the Pee Dee River
from Blewett Falls Lake to Hitchcock Creek has a Class C classification (NCDWQ 2007). Class
W S -V &B waters are designated as drinking water supplies and primary recreation while Class C
are designated for propagation of aquatic life and secondary recreational uses.
1 -2

Section 2 - Study Objectives
The objective of this study was to assess the spatial and temporal patterns of DO concentrations
in the Pee Dee River downstream of the Tillery and Blewett Falls Hydroelectric Plants using
in -situ continuous monitoring instruments from May through October, 2010. The study
evaluated the longitudinal (upstream to downstream) and latitudinal (east bank to west bank)
differences in the DO regime in the Pee Dee River with power plant operations over a seasonal
period of hypolimnetic stratification and de- stratification of the Project reservoirs. Monitors
were placed below each power plant and within the river sections designated or previously
designated by the NCDWQ as impaired due to low DO concentrations under Section 303(d) of
the Clean Water Act. A secondary study objective was to continuously monitor temperature, pH,
and specific conductance.
2 -1

Section 3 - Site Description
3.1 Reach 1 - Pee Dee River Below the Tillery Development
The 2010 study area for Reach 1 was a 4.6 -mile reach of the Pee Dee River in south - central
North Carolina located immediately below the Tillery Development to above the confluence of
the Rocky River (Figure 3 -1). Reach 1 immediately below the Tillery Development is generally
shallow with runs, shoals, large substrate, and bedrock outcroppings. River conditions are
similar downstream until the Rocky River confluence, approximately 5 miles downstream of the
Tillery Dam. From the Rocky River confluence to the downstream extent of Reach 1, pools and
deep runs with smaller substrate such as sand, silt and organic detritus become more common.
Several tributaries enter into Reach 1 (Figure 3 -1). Clarks Creek enters into Reach 1 from the
east just upstream of the N.C. Highway 731 Bridge. The Town of Mount Gilead's Wastewater
Treatment Plant discharges into Clarks Creek. The Rocky River, the largest tributary in the
reach, converges with the Pee Dee River from the west, approximately five miles below the
Tillery Dam. The Rocky River watershed includes several urban communities such as
Mooresville, Kannapolis, Concord, Huntersville, and eastern portions of Charlotte. Urban as well
as agricultural nonpoint sources of runoff and point sources of discharge have contributed to
degraded water quality in the Rocky River. Turbidity and fecal coliform have been noted as
water quality parameters of concern in sections of the Rocky River by the NCDWQ and the
Yadkin -Pee Dee River Basin Association ( NCDWQ 2008b, 2010). These two parameters were
in excess of applicable state water quality standards in more than 10 percent of samples collected
during the assessment period. Brown Creek flows through the Pee Dee National Wildlife Refuge
and enters into Reach 1 from the west approximately one mile upstream of the N.C. Highway
109 Bridge. Brown Creek from the mouth of Lick Creek to the confluence of the Pee Dee River
has an overall impaired use due to impaired biological integrity and low DO concentrations
( NCDWQ 2010). Two small tributaries, Cedar Creek and Turkey Top Creek, enter into Reach 1
below the N.C. Highway 109 Bridge.
3.2 Reach 2 - Pee Dee River Below the Blewett Falls Development
The 2010 study area for Reach 2 was a 2.1 -mile reach of the Pee Dee River in south - central
North Carolina from below the Blewett Falls Development to the Cartledge Creek confluence
(Figure 3 -2). Reach 2 has shoals, riffles, runs, and pools with a wide range of substrate sizes and
bedrock outcroppings. River conditions are similar throughout Reach 2. Shoals are
intermittently located within the reach, which indicate substantial drops in river channel gradient.
One named tributary enters into Reach 2 of the Pee Dee River (Figure 3 -2). Cartledge Creek
enters into the Pee Dee River from the east approximately two miles below the Blewett Falls
dam.
3 -1

Section 3 Site Description
Tillery Hydroelectric Development
�` �l Uwharrie River
APGI Falls Dam N
Mountain
Creek
v
Jacobs
Creek
Lake Tillery
STANLY
COUNTY
Cedar
Creek
I\
Continuum
Water Quafty Monitor
Locatiom
IWaa
11UaYrat
Letnar
rsa (D.t. xanp
]Lar.w.dr o..rort.
L.t.nu..t.ya<mwpoanno.a
rCllt.t (Pa Do &va)
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t3 Wn Dn lliva)
quNiry
en Baars NC Hyha�a 711 . 1.
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AM 1115 � & «4y R�vn rooavmve•
MONTGOMERY
h� COUNTY
Clarks
Creek
Tillery Dam
TYC M 1 -1
TYCM1 -2
TYCM1 -3
Rocky River /
RICHMOND
COUNTY
TYC M 2
ANSON
COUNTY
Legend
♦ Connni i, ntorLaftpns
7j^ NCCnaL: -, i..i. .. ere for Di5zo1ve00rygan
2 3
oraang5mn fv.urax m:a.yua:oa.e.r. att� •anv.c f..r w. ncpyoiDwtruvofv
Turkey Top
Creek
Brown Creek
Figure 3 -1 Map of the Tillery Development and Reach 1 of the Pee Dee River showing
continuous water quality monitoring stations.
3 -2

Section 3 Site Description
Blewett Falls Hydroelectric Development
Little River_:,,
Mountain
Creek
RICHMOND
ANSON
COUNTY COUNTY
Blewett Falls Lake(
Buffalo Cartledge
Creek Creek
4N
, 1'- Blewett Falls Dam 1
FpF62 /
U
Continuous Water Quality Monitor Locations
Swflon
hloidiGring it
L—d-
BM (BI—Mftl.L�)
Wd
d— -d -
wean
-1 (P. D—)
Cmfiu v—
fl., wfw buoy
.1 Uf 1881
B.1— lie P—.". —I UN ed.'
Buoy . ni I a' 4
qualify
- 111'1-IA IA
Thompson
BFCM2A Creekk
Island Hitchcock
Creek Creek
MARLBORO
COUNTY
Jones
Creek
SOCIETY HILL, SC
CHESTERFIELD T tI, I A I I
COUNTY not to -"Ie
Flat
NC Creek
te Line
SC
MARLBORO
COUNTY
Westfield
Creek
Legend
A,
CHESTERFIELD
COUNTY
DARLINGTON
COUNTY
N
d1k
DILL OTN
COUN Y
Black
Creek
m3m=
FLORENCE
COUNTY
FLORENCE.4-
SC
Mles
Figure 3-2 Map of the Blewett Falls Development and Reach 2 of the Pee Dee River
showing continuous water quality monitoring stations.
3-3

Section 4 - Methods
4.1 Continuous Monitor Locations
Continuous monitor stations were located in the upper, middle, and lower sections of the
monitored reaches below the Tillery and Blewett Falls Developments (Table 4 -1 and Figures 3 -1
and 3 -2). In Reach 2, the lowermost Station (Station BFCM2A) was located 2.1 miles
downstream of the Blewett Falls Dam. Prior to selecting the continuous monitor stations in
2004, lateral and vertical water quality measurements were made at cross - channel transects to
determine any significant spatial differences in DO concentrations across the river channel
(Progress Energy 2005b). Station locations were chosen to be representative of the river channel
area with the lowest DO concentrations. These same station locations were used in the
2004 -2008 continuous monitoring programs. On June 11, 2008, Stations TYCM3, TYCM4,
BFCM2 and BFCM3 were dropped from the monitoring program. Stations TYCM1 -2,
TYCM1 -3 and BFCM2A were subsequently added to the monitoring program on this same date
to better assess spatial DO concentrations in the immediate tail waters. The NCDWQ approved
these modifications to the monitoring program.
Table 4 -1 Description of station locations used in the continuous water quality study in
Reaches 1 and 2 of the Pee Dee River below the Tillery and Blewett Falls
Hydroelectric Plants, 2010.
Transect Station Location Description (approximate river miles below each power plant dam)
Reach 1 Tillery Hydroelectric Plant
TYCMl -1 East Bank of N.C. Highway 731 Bridge (0.4 mile)
TYCMl -2 Mid - Channel of N.C. Highway 731 Bridge (0.4 mile)
TYCMl -3 West Bank of N.C. Highway 731 Bridge (0.4 mile)
TYCM2 Above Rocky River confluence (4.6 miles)
Reach 2 Blewett Falls Hydroelectric Plant
BFCMl Power Plant Tailrace Buoy Line (0. l mile)
BFCMIA Below Peninsula Separating Power Plant Tailrace and Dam (0.7 mile)
BFCM2A Below Cartledge Creek confluence (2.1 miles)
Selection of the continuous monitor stations was based on the results of the cross - channel DO
measurements, suitable water depth, access to monitors, availability of permanent structures for
anchoring monitors, and protection from floating debris and vandalism. In some instances,
continuous monitors were cabled to bridge pilings, while other monitors were held in place by
anchors placed on the river bottom (Table 4 -2). The location of the continuous monitor at
Station TYCM2 was changed during 2005. It was moved to the east side of the river channel
because previous studies showed that DO concentrations were often lower on the east side.
Because the river is very shallow in this sub -reach with few deep areas, the monitor was also
moved upstream approximately 100 m.
4 -1

Section 4 Methods
Table 4 -2 Locations, GPS coordinates, water depths, and types of deployment for seven
continuous water quality monitor stations in Reaches 1 and 2 of the Pee Dee
River below the Tillery and Blewett Falls Developments.
GPS Water
Station Location Coordinates Depth Type of Deployment
TYCMI -1
N.C. Highway 731 Bridge
35� 12' 03.48" N
0.4 -2.0 m
In a Stationary, vertical PVC pipe
floats and anchored with a heavy
piling near the east shore
80� 03' 41.41" W
weight
cabled to the bridge piling
TYCMI -2
N.C. Highway 731 Bridge
350 12' 02.52" N
0.4 -2.0m
In a Stationary, vertical PVC pipe
Cartledge Creek.
piling near the mid - channel
800 03' 41.84" W
cabled to the bridge piling
350 12' 01.45" N
TYCMI -3
N.C. Highway 731 Bridge
800 03' 45.35" W
0.4 -2.0m
In a Stationary, vertical PVC pipe
Piling near the west channel
cabled to the bridge piling
TYCM2
In a shallow run near the east
35� 09' 01.60" N
0.4 -1.5 m
Suspended in water column by
bank 1 km upstream of the
80� 04' 17.12" W
floats and anchored with a heavy
Rocky River confluence
weight
BFCMI
Midway on the safety buoy line
34� 59' 00.24" N
2.0 -3.5 m
Tethered to the safety buoy line
in the power plant tailrace
79� 52' 34.00" W
cable with an anchor on the river
bottom
BFCMIA In a shallow run downstream of
34� 58' 59.92" N
1.0 -2.0 m Suspended in water column by
the peninsula separating the
79� 52' 12.77" W
floats and anchored with a heavy
tailrace and dam
weight
BFCM2A In a pool just below a rock
340 58' 04.30" N
2.5 -3.5 m Suspended in water column by
shoal below the confluence of
790 51' 58.63" W
floats and anchored with a heavy
Cartledge Creek.
weight
4.2 Continuous Monitor Deployment
YSI9 600XLM continuous monitors were selected to monitor water quality in the 2004 -2010
monitoring studies (YSI 2003). All continuous monitors were placed in a sleeve section of
two -inch diameter PVC pipe for protection. Holes were drilled in the lower end of the PVC pipe
to allow water to move freely around the continuous monitor probes. Five different deployment
techniques were used for the continuous monitors depending on the station location (Table 4 -2).
Continuous monitors were anchored to permanent structures such as bridge pilings when
available. Otherwise, continuous monitors were anchored to the river bottom by a heavy weight
and suspended in the water column beneath foam floats. Continuous monitors at stations
TYCM1 -1, TYCM1 -2 and TYCM1 -3 maintained stationary positions and were capable of
recording accurate depth data.
Continuous monitors were deployed below the Tillery and Blewett Falls developments in late
April and began logging data on May 1, 2010. Continuous monitors were programmed to record
temperature, DO, pH, specific conductance and depth at 15- minute intervals. During 2004, a
28- second warm up period was used for the DO probes. A 40- second warm up period was used
4 -2

Section 4 Methods
for the DO probes in 2005 -2010. All continuous monitors were removed from the river on
October 31 of each year after the 2004 monitoring year.
4.3 Continuous Monitor Service and Calibration
Continuous monitors were calibrated in the laboratory prior to deployment. Continuous
monitors were field- checked /calibrated against known pH and conductivity standards during
routine field servicing. Dissolved oxygen membranes were changed during service, and DO was
air - calibrated prior to each deployment. Additionally, continuous monitors were cleaned and
data were uploaded during service. Temperature probes were checked when continuous
monitors were returned to the laboratory for service, cleaning, and calibration during the study.
The continuous monitors were scheduled to be serviced and calibrated biweekly and rotated
among stations during the May through October monitoring period. Rotating continuous
monitors reduced the time that data were not recorded and helped determine if any data
anomalies were due to station environmental conditions or continuous monitor performance.
Continuous monitors that were not deployed in the field were returned to the laboratory for
service, cleaning, and calibration. All YSI® 600XLM continuous monitors had a unique
identification number which permitted instrument performance tracking during the study.
4.4 Data Validation and Review
Each YSIg 600XLM continuous monitor was compared against a laboratory- and field - calibrated
YSI9 Model 650 multi - parameter instrument during the field servicing. All continuous monitor
data were combined for each station and then reviewed and edited to determine if any data
needed to be omitted due to equipment performance issues. Water quality data were recorded in
the field and retained for analysis for 93.1 -100 percent of the time that continuous monitors were
deployed (Tables A -1). Data were omitted if there was a problem with one or more of the YSI®
600XLM continuous monitor probes based on the instrument -to- instrument comparisons.
Periods when data were not logged at each station and the reason(s) why the continuous monitor
malfunctioned or why recorded data were omitted after review are listed in Table A -2.
4.5 Quality Assurance and Quality Control
All continuous monitoring data were collected in accordance with Progress Energy's Quality
Assurance /Quality Control (QA/QC) Program (Progress Energy 2007b, 2007c and 2008). In
addition, Progress Energy filed a draft Quality Assurance Project Plan (QAPP) with the
NCDWQ in its 401 Water Quality Certificate application, dated May 11, 2007 (Progress Energy
2007a). The QAPP specifies the QA/QC framework that was followed during the conduct of
these studies.
Progress Energy is certified by the NCDWQ and the South Carolina Department of Health and
Environmental Control to collect water quality and biological samples through Standard
Operating Procedures. Specific procedures for instrument calibration and water quality
sampling, including sample handling and chain -of- custody, are detailed in Progress Energy's
QA/QC Program and the QAPP.
4 -3

Results and Discussion
Section 5 — Environmental and Reservoir Conditions
5.1 Environmental Conditions
5.1.1 Climatological Conditions
The long -term annual precipitation average at Wadesboro, North Carolina (COOP Station
318964) for the 1938 -2010 period was 118.6 cm. Precipitation during 2010 (89.5 cm) was less
than the long term annual average. The long -term monthly precipitation average was surpassed
in January, May and September (Figure 5 -1). Monthly precipitation totals for 2010 ranged from
1.4 cm of precipitation in October to 14.2 cm of precipitation in September.
40.0
35.0
30.0
25.0
0
't� 2 0. 0
a.
15.0
a
10.0
5.0
0.0
4 �
Month
2010 Monthly Precipitation Totals — — 72 Year Precipitation Mean
• - 72 Year Precipiation Minimum — - 72 Year Precipiation Maximum
Figure 5 -1 Comparison of monthly precipitation totals during the 2010 period to the
72 -year monthly minimum, maximum, and mean precipitation for the period
1938 to 2010. (Data Source: Wadesboro, North Carolina COOP Station
318964).
5 -1
' ♦
i
Month
2010 Monthly Precipitation Totals — — 72 Year Precipitation Mean
• - 72 Year Precipiation Minimum — - 72 Year Precipiation Maximum
Figure 5 -1 Comparison of monthly precipitation totals during the 2010 period to the
72 -year monthly minimum, maximum, and mean precipitation for the period
1938 to 2010. (Data Source: Wadesboro, North Carolina COOP Station
318964).
5 -1

Section 5 Environmental and Reservoir Conditions
Mean monthly air temperatures were generally above the 1938 -2010 long -term average for the
majority of 2010 (Figure 5 -2). Monthly average air temperatures ranged from 17.5 °C (October)
to 27.8 °C (July) during the May through October monitoring period (Figure 5 -2). Based on the
long -term monthly averages, 2010 was 0. VC warmer than the 72 year average.
35.0
30.0
25.0
U
0— 20.0
15.0
s,
a.
5 10.0
E�
5.0
0.0
dop
/
/ / \ �\
wo
\ \
/ r
-5.0
4
Month
2010 Monthly Average Temperature — — 72 Year Temperature Mean
— • -72 Year Temperature Min — -72 Year Temperature Maximum
Figure 5 -2 Comparison of mean monthly air temperatures during the 2010 period with
the 72 -year monthly minimum, maximum and mean air temperatures for the
period 1938 to 2010 (Source: Wadesboro, North Carolina COOP Station
318964).
5.1.2 River Flow Conditions
The stream flow gage for the Rocky River at the N.C. Highway 52 Bridge (USGS 02126000)
reflected local and watershed precipitation events (Figure 5 -3). The stream flow gage for the Pee
Dee River at the U.S. Highway 74 Bridge (USGS 02129000) reflected watershed precipitation
events as well as Blewett Falls Hydroelectric Plant operations. Daily mean stream flow for the
Rocky River ranged from 74 cfs (September 23) to 38,700 cfs (February 6), and averaged
1,124 cfs. Daily mean stream flow at the U.S. Highway 74 Bridge ranged from 959 (June 26) to
96,200 cfs (February 6), and averaged 7,571 cfs.
5 -2

Section 5 Environmental and Reservoir Conditions
45,000
40,000
w
35,000
0 30,000
25,000
20,000
15,000
10,000
A 5,000
0
1 -Jan
Rocky River at the N.C. Highway 52 Bridge (USGS 02126000)
120,000
20 -Feb 10 -Apr 30 -May 19 -Jul 7 -Sep 27 -Oct 16 -Dec
Date
Pee Dee River at the U.S. Highway 74 Bridge (USGS 02129000)
w
100,000
F° 80,000
60,000
s,
40,000
20,000
A
0
1 -Jan 20 -Feb 10 -Apr 30 -May 19 -Jul 7 -Sep 27 -Oct 16 -Dec
Date
Figure 5 -3 Daily mean stream flow for the Rocky River at the N.C. Highway 52 Bridge
and the Pee Dee River at the U.S. Highway 74 Bridge, 2010.
Power plant discharge never exceeded 20,000 cfs below the Tillery Hydroelectric Plant
(Figure 5 -4). Water spilling over the dam did not occur during 2010. For the May through
October monitoring period, more power generated flows occurred during May and June than any
other months, while the least flow occurred during September and October. The number of days
from May 1 to October 31 without any power generation during a 24 -hour period at the Tillery
Hydroelectric Plant totaled 2 days.
5 -3

Section 5
20,000
18,000
w 16,000
14,000
F° 12,000
c 10,000
8,000
s,
6,000
U� 4,000
2,000
0
30 -Apr 20 -May
Environmental and Reservoir Conditions
9 -Jun 29 -Jun 19 -Jul 8 -Aug 28 -Aug 17 -Sep 7 -Oct 27 -Oct
Date
Figure 5 -4 Plant discharge (cfs) at the Tillery Hydroelectric Plant, May- October 2010.
During the 2010 monitoring period, plant discharge estimates never exceeded 10,000 cfs below
the Blewett Falls Hydroelectric Plant (Figure 5 -5). Power generation in May was greater than
any other month, while the least amount of power generation occurred during September. The
Blewett Falls Plant released flows every day during the monitoring period and for more than 24
consecutive hours on several occasions from May through October.
10,000
9,000 ,
8,000
w
7,000
0 6,000
w
5,000
4,000
3,000
2,000
1,000 - —
0
30 -Apr 20 -May 9 -Jun 29 -Jun 19 -Jul 8 -Aug 28 -Aug 17 -Sep 7 -Oct 27 -Oct
Date
Figure 5 -5 Plant discharge (cfs) at the Blewett Falls Hydroelectric Plant, May- October
2010.
5 -4

Section 5 Environmental and Reservoir Conditions
5.2 Dissolved Oxygen in Project Reservoirs
5.2.1 Lake Tillery
The intake structure at the Tillery Hydroelectric Plant extends from 12 to 19 m below the surface
of Lake Tillery at the normal maximum operating elevation (277.3 ft)'. Vertical profiles of DO
concentrations were taken at least once a month at Station B2 on Lake Tillery near the intake
structure (Figures 3 -1 and 5 -6). In May of most monitored years (Progress 2005b, 2006a, 2006c
and 2010), Lake Tillery was well -mixed and DO concentrations were similar throughout the
water column (Figure 5 -6). In June of most monitored years stratification (i.e., change of >1
mg/L per meter of depth) occurred at or below four meters (Figure 5 -6). Dissolved oxygen
concentrations were stratified in the lake during July, August, September and the early part of
October, and DO concentrations were less than 5.0 mg/L below 7 m. Dissolved oxygen
concentrations at the intake depth (12 -19 m) were < 4.0 mg/L from June - September. Dissolved
oxygen stratification disappeared during early October, as DO concentrations were above 5 mg/L
and similar throughout the water column. The period of DO stratification in 2010 was greater
than that for the 2006 -2009 periods (Progress 2010).
0.0
2.0
4.0
6.0
8.0
a.
10.0
A 12.0
14.0
16.0
18.0
20.0
Dissolved Oxygen (mg/L)
0.0 2.0 4.0 6.0 8.0 10.0 12.0
5/3/2010
5/27/2010
6/16/2010
7/6/2010 7/20/2010
8/25/2010
9/7/2010
10/4/2010
11/1/2010
Figure 5 -6 Vertical profiles of dissolved oxygen concentrations measured at Station B2
at Lake Tillery, May through November, 2010.
' Unless otherwise noted, all elevations are NAVD 88 datum. The NAVD 88 datum is 0.9 feet lower than the 1929
NGVD datum.
5 -5

Section 5
5.2.2 Blewett Falls Lake
Environmental and Reservoir Conditions
The intake structure at the Blewett Falls Hydroelectric Plant extends from approximately 6 to
10 m below the lake surface at the normal maximum operating elevation (177.2 ft)'. Vertical
profiles of temperature and DO concentrations were taken at least once a month at Station B2
located near the Blewett Falls Dam. This station is adjacent to the power plant intake canal
(Figures 3 -5 and 5 -7). Station B2 was usually 7 to 9 m deep depending upon lake level
elevation. Dissolved oxygen concentrations were >5.0 mg/L throughout the water column
during May and stratified by mid -late June. Dissolved oxygen concentrations at the intake depth
(6 -10 m) were <4.0 mg /L from July to early September. From mid -late September through
October DO concentrations were above 5.0 mg/L throughout the water column (Figure 5 -7).
Dissolved Oxygen (mg/L)
0.0 2.0 4.0 6.0 8.0 10.0
0.0
1.0
2.0
3.0
4.0
5 5.0
A
6.0
7.0
8.0
9.0
Figure 5 -7
12.0
5/3/2010
5/27/2010
6/7/2010
6/29/2010
7/19/2010
8/25/2010
9/7/2010
9/21/2010
10/4/2010
11/1/2010
Vertical profiles of dissolve oxygen concentrations measured at Station B2 at
Blewett Falls Lake, May through November, 2010.
5 -6

Section 6 - 2010 Water Quality Results
6.1 Water Quality in the Pee Dee River, 2010
6.1.1 Dissolved Oxygen - Tillery Dam to Turkey Top Creek (Reach 1)
During the May through October monitoring period, instantaneous DO concentrations in Reach 1
ranged from 0.2 to 17.2 mg/L at the four monitoring stations in Reach 1 (Table 6 -1). Mean DO
concentrations at these four stations ranged from 4.6 to 6.4 mg/L (Table 6 -1). Throughout
Reach 1, DO concentrations exhibited a seasonal trend by decreasing during May and June;
remaining at a seasonal low during July and August; rising during early September; fluctuating
during September and early October; then rising during mid and late October (Figures 6 -1 and
6 -2).
Table 6 -1 Dissolved oxygen concentration summary for Reach 1 of the Pee Dee River
below the Tillery Hydroelectric Plant, May 1 to October 31, 2010.
Dissolved Oxygen (DO) Variable
TYCM1 -1
Reach 1 Stations
TYCM1 -2 TYCM1 -3
TYCM2
Mean DO (mg/L) ¶
4.6
4.8
5.5
6.4
Range of DO (mg/L)
0.2 -12.1
1.4 -14.7
1.2 -17.2
1.8 -17.2
Percent of DO concentrations < 5.0 mg/L
56.3%
57.1%
50.7%
44.3%
Percent of DO concentrations < 4.0 mg/L
46.1%
41.9%
37.1%
29.3%
Percent of DO concentrations < 3.0 mg/L
29.0%
19.5%
18.7%
5.2%
Percent of DO concentrations < 2.0 mg/L
11.8%
3.5%
1.9%
0.1%
Date of lowest DO concentration
18 -Jul
27 -Jul
19 -Jul
13 -Jul
First DO concentration < 5.0 mg/L
21 -May
1 -May
1 -May
11 -May
Last DO concentration < 5.0 mg/L
26 -Oct
15 -Oct
18 -Oct
7 -Sep
First DO concentration < 4.0 mg/L
26 -May
30 -May
1 -May
16 -Jun
Last DO concentration < 4.0 mg/L
23 -Sep
14 -Oct
15 -Oct
7 -Sep
First DO concentration < 3.0 mg/L
19 -Jun
6 -Jun
11 -May
18 -Jun
Last DO concentration < 3.0 mg/L
22 -Sep
26 -Sep
12 -Sep
6 -Sep
First DO concentration < 2.0 mg/L
23 -Jun
6 -Jul
17 -Jun
13 -Jul
Last DO concentration < 2.0 mg/L
8 -Sep
17 -Aug
19 -Aug
19 -Jul
Longest duration of DO < 5.0 mg/L (hours)
63.5
58.3
40.8
26
Start of longest duration of DO < 5.0 mg/L
17 -Aug
17 -Aug
20 -Aug
18 -Aug
¶ Mean of all measurements for the monitoring period of May 1 to October 31, 2010.
6 -1

Section 6 2010 Water Quality Results
Tillery Reach 1 -2010
11
10
F]
J 8
of
E 7
6
O 5
d
0
4
C3 3
2
1
0�
05/01/10
06/01/10 07/01/10 08/01/10 09/01/10 10/01/10
Date
- - - TYC M1 -1 TYC M1 -2 � , TYC M1 -3 M -jVl TYC M2
11/01/10
Figure 6 -1 Weekly mean dissolved oxygen concentrations at continuous monitor stations
in Reach 1 of the Pee Dee River below the Tillery Hydroelectric Plant, May 1
to October 31, 2010.
6 -2

Section 6 2010 Water Quality Results
Tillery Reach 1, Station TYCM1 -1 -2010
19
18
17
16
15
14
J 13
12
a�
11
X
10
O 9
v
> 8
0
�n 7
to
0 6
5
4
3
2
1
0
05/01/2010 06/01/2010 07/01/2010 08/01/2010 09/01/2010 10/01/2010 11/01/2010
Date
19
18
17
16
15
14
J 13
E 12
� 11
a�
10
X
O 9
v
> 8
0
Cn 7
M
D 6
5
4
3
2
1
0
05/01/2010 06/01/2010 07/01/2010 08/01 /2010 09/01/2010 10/01/2010 11/01/2010
Date
Tillery Reach 1, Station TYCM1 2 -2010
Figure 6 -2 Daily averages (black line) and ranges (vertical bars) of dissolved oxygen
concentrations at Stations TYCM1 -1, TYCM1 -2, TYCM1 -3 and TYCM2 in
Reach 1 of the Pee Dee River below the Tillery Hydroelectric Plant, May 1 to
October 31, 2010.
6 -3

Section 6 2010 Water Quality Results
Tillery Reach 1, Station TYCM1-3 -2010
19
18
17
16
15
14
13
12
11
a
lo-
9-
v
a� 8
0
to 7
to
0 6
S
4
3
2
1
O
05/01/2010 06/01/2010 07/01/2010 08/01/2010 09/01/2010
Date
19
18
17
16
15
14
J 13
12
11
a 10
x
O 9
v
8
Cn
to 7
Mn
0 6
5
4
3
2
1
O
Tillery Reach 1, Station TYCM2 - 2010
10/01/2010 11/01/2010
05/01/2010 06/01/2010 07/01/2010 08/01/2010 09/01/2010 10/01/2010
Date
Figure 6 -2 (continued).
Dissolved oxygen concentrations less than 1.0 mg/L occurred occasionally between July 11 and
August 12 at Station TYCM1 -1. However, these DO concentrations below 1.0 mg/L only
occurred for short periods of time ( <4% of total observations) (Figure 6 -3). At all stations, the
lowest DO concentrations occurred from mid -late July (Figure 6 -2, Table 6 -1). On July 18, the
lowest DO concentration of 0.2 mg/L occurred at Station TYCM1 -1 (Table 6 -1). Time periods
with exceptionally low levels of DO ( <2.0 mg/L) occurred from late June through early
September, during the overnight to the early morning time period with no power generation flow
(Figure 6 -4).
6 -4

Section 6 2010 Water Quality Results
25
KII
_
m
15
a
a
a�
Cr
10
m
L
LL
5
0
THIMReach 1- 2010
0 -1 1 -2 2-3 3-4 4-6 5-6 6 -7 7-8 8-9 9- 1010- 1111 -1212 -1313- 1414 -1515 -1616- 17'17 -18
Dissolved Oxygen (mg/L)
TYCM1 -1 � TYCM1 -2 TYCM1 -3 TYCM2
Figure 6 -3 Frequency distributions of dissolved oxygen concentrations at continuous
monitor stations in Reach 1 of the Pee Dee River below the Tillery
Hydroelectric Plant, May 1 to October 31, 2010.
6 -5

Section 6 2010 Water Quality Results
20
15
a�
P
bA
10
0
.O
U
7
O
5
0
0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00
Time
TYCMl -1 TYCMl -2 TYCMl -3 TYCM2 Flow
20000
15000
w
U
10000
_O
�I
5000
0
Figure 6 -4 Dissolved oxygen concentrations and power plant generation flows in
Reach 1 of the Pee Dee River below the Tillery Hydroelectric Plant, July 18
to July 22, 2010.
Dissolved oxygen concentrations throughout Reach 1 fluctuated widely on most days during the
study period (Figures 6 -2 and 6 -4). These daily fluctuations were most apparent at Station
TYCM2 where DO concentrations often fluctuated by more than 9.0 mg/L during July.
Dissolved oxygen concentrations on July 13 ranged from 1.8 mg/L (lowest recorded at this
station) to 10.8 mg/L. Dissolved oxygen concentrations were often supersaturated and exceeded
17.0 mg /L and 200 percent saturation on some occasions during May. Station TYCM2 was the
shallowest of the monitored stations, and changes in river flow, coupled with diurnal fluctuations
associated with algal photosynthesis and respiration, likely contributed to these DO conditions.
Weekly mean DO concentrations varied throughout Reach 1 (Figure 6 -1). However, weekly
mean DO concentrations for Station TYCM1 -2, TYCM1 -3, and TYCM2 were typically greater
than weekly mean DO concentrations at Station TYCM1 -1.
Station TYCM1 -1 had more instantaneous DO concentrations below 4.0 mg/L (46.1 %) than
other stations in Reach 1 (29.3 - 41.9 %) (Table 6 -1 and Figure 6 -3). Stations TYCM1 -1 and
TYCM1 -2 had the greatest percentage of DO concentrations <5.0 mg/L (56.3% and 57.1%
6 -6

Section 6 2010 Water Quality Results
respectively) when compared to other Reach 1 stations. Station TYCM2 differed from other
stations with a wider distribution of DO concentrations, including a greater percentage of DO
concentrations greater than 10.0 mg/L (Figure 6 -3).
The percentage of instantaneous DO concentrations below 5.0 mg/L in Reach 1 generally
decreased with increased distance from the Tillery Hydroelectric Plant. Nearly 57 percent of the
instantaneous DO concentrations recorded at Stations TYCM1 -1 and TYCM1 -2 from May
through October were less than 5.0 mg/L (Table 6 -1). The percent of DO concentrations below
5.0 mg/L decreased at the downstream station to a low of 44.3 percent at Station TYCM2. The
percentage of instantaneous DO concentrations below 5.0 mg /L also decreased from the east
bank to west bank along the N.C. Highway 731 Bridge (56.3% and 50.7% respectively).
In Reach 1, instantaneous DO concentrations first decreased below 5.0 mg/L on May 1 at
Stations TYCM1 -2 and TYCM1 -3 (Table 6 -1). Dissolved oxygen concentrations below 5.0
mg/L were recorded on many days at stations in Reach 1 through October. The last DO
concentration below 5.0 mg/L in Reach 1 was recorded at Station TYCM1 -1 on October 26.
The lowest recorded instantaneous DO concentration during the study period was 0.2 mg/L at
Station TYCM1 -1. Dissolved oxygen concentrations remained below 5.0 mg/L for almost three
consecutive days in mid August at Station TYCM1 -1 (Table 6 -1). At all other stations, the
longest duration of DO concentrations below 5.0 mg/L occurred during the mid August time
frame.
6.1.2 North Carolina Water Quality Standards for DO in Reach 1
The North Carolina water quality standards for DO require a daily average DO concentration of
at least 5.0 mg/L and all instantaneous DO concentrations must be at least 4.0 mg/L (NCDWQ
2007). Dissolved oxygen concentrations were below one or both water quality standards at all
four stations in Reach 1 for varying periods of time in 2010. Both water quality standards were
not met for at least 74 days from May through October, depending on the station (Table 6 -2;
Figures 6 -3 and 6 -4). The period during which the daily average DO standard was not met in
Reach I extended from June 6 through September 29. Instantaneous DO concentrations in
Reach 1 initially decreased below 4.0 mg/L on May 1 and concentrations less than 4.0 mg/L
were recorded on some days until October 15 (Table 6 -2).
6 -7

Section 6 2010 Water Quality Results
Table 6 -2 Assessments of daily dissolved oxygen concentrations from May 1 to October
31, 2010 at stations in Reach 1 of the Pee Dee River below the Tillery
Hydroelectric Plant compared to the North Carolina dissolved oxygen water
quality standards.
North Carolina Water Quality Standard
TYCM1 -1
Reach 1 Stations
TYCMI -2 TYCM1 -3
TYCM2
Daily average DO (5.0 mg /L)
Number of days not meeting standard
90
94
76
27
First day standard was not met
17 -Jun
6 -Jun
9 -Jun
18 -Jun
Last day standard was not met
23 -Sep
29 -Sep
29 -Sep
28 -Aug
Instantaneous DO (4.0 mg /L)
Number of days not meeting standard
90
119
128
74
First day standard was not met
26 -May
30 -May
1 -May
16 -Jun
Last day standard was not met
23 -Sep
14 -Oct
15 -Oct
7 -Sep
Number of days either standard was not met+
91
119
128
74
Number of days assessed
146¥
154¥
172¥
123¥
+The total number of days that one or both of the North Carolina water quality standards for daily average
(5.0 mg/L) and instantaneous (4.0 mg/L) DO concentrations were not met.
¶The number of days assessed was the total number of days from May 1 to October 31 when DO concentrations
were recorded for at least half of the day.
¥ Appendix A.
At Station TYCM1 -1, DO concentrations were below one or both North Carolina water quality
standards for 91 non - consecutive days from May 26 to September 23 (Table 6 -2 and Figure 6 -2).
Instantaneous DO concentrations below 4.0 mg/L and daily average concentrations below
5.0 mg /L occurred on the same days. At Station TYCM1 -1, instantaneous DO concentrations
below 4.0 mg/L and daily average DO concentrations less than 5.0 mg/L occurred on 90 days
from May through September (Table 6 -2).
At Station TYCM1 -2, DO concentrations were below one or both North Carolina water quality
standards for 119 non - consecutive days from May 30 to October 14 (Table 6 -2 and Figure 6 -2).
Instantaneous DO concentrations below 4.0 mg/L and daily average concentrations less than
5.0 mg/L typically occurred on the same days. At Station TYCM1 -2, instantaneous DO
concentrations below 4.0 mg/L occurred on 119 days whereas daily average DO concentrations
below 5.0 mg/L occurred on 94 days from June through September (Table 6 -2).
Dissolved oxygen concentrations were below each of the North Carolina water quality standards
more frequently at Station TYCM1 -3 than at other Reach 1 stations. At Station TYCM1 -3, DO
concentrations were below one or both water quality standards on 128 non - consecutive days
6 -8

Section 6 2010 Water Quality Results
from May 1 to October 15 (Table 6 -2 and Figure 6 -2). At Station TYCM1 -3, instantaneous DO
concentrations below 4.0 mg/L occurred on 128 days (Mayl- October 15) whereas daily average
concentrations below 5.0 mg/L occurred on 76 days (June 9- September 29) (Table 6 -2).
At Station TYCM2, DO concentrations were below one or both North Carolina water quality
standards for 74 non - consecutive days from June 16 to September 7 (Table 6 -2 and Figure 6 -2).
Instantaneous DO concentrations below 4.0 mg/L and daily average concentrations below
5.0 mg/L typically did not occurred on the same days. At Station TYCM2 instantaneous DO
concentrations below 4.0 mg/L occurred on 74 days whereas daily average DO concentrations
below 5.0 mg/L occurred on 27 days from June through September.
6.1.3 Operational Effects of the Tillery Hydroelectric Plant
Dissolved oxygen concentrations in Reach 1 were affected by natural diel cycles (algal
respiration - photosynthesis), power plant operations, and tributary inflow. The relative degree of
algal respiration effect on DO concentrations compared to power plant operations could not be
readily partitioned out with this monitoring program. Similar to observations in previous studies
(Progress Energy 2005b,2006c, 2010), there were strong diel cycles in DO concentrations at all
monitored stations, which likely reflected the influence of algal photosynthesis and respiration
on DO dynamics at these shallow stations . These diel cycles were apparent on days of no power
plant generation (Figure 6 -5). Dissolved oxygen concentrations typically changed by 4 to 8
mg/L during a 24 -hour period at all monitored stations. On days without power generation, the
DO concentrations would begin to rise around dawn; peak during early afternoon; decrease
through the early evening; and then remain low until the next day (Figure 6 -5).
When in- stream flows increased with power generation, the DO concentrations correspondingly
decreased during periods of hypolimnetic DO stratification (Figure 5 -6, 6 -4, and 6 -6). This
effect was particularly evident when generation began several hours after DO concentrations
began to rise in the morning hours. Dissolved oxygen concentrations would then decline to
levels just above the pre -dawn concentrations (Figure 6 -4 and 6 -6 and Progress Energy 2005b,
2010). The diel response of DO also showed seasonal shifts with greater peaks in DO
concentrations during the days of longer daylight length and higher water temperatures (late May
through September) when there was greater photosynthetic activity as opposed to the days of
shorter daylight length and lower water temperatures (early May and October) (Figure 6 -2).
6 -9

Section 6 2010 Water Quality Results
12
9
an
O
6
0
A 3
0 4—
0:00
3:00 6:00 9:00 12:00 15:00
Time
18:00 21:00
TYCMl -1 — TYCMl -2 TYCM2
Figure 6 -5 Dissolved oxygen concentrations (mg/L) on July 3 with no power plant
generation flows at Stations TYCM1 -1, TYCM1 -2 and TYCM2.
Power generation affected the daily DO maximums and daily DO means more than daily DO
minimums at Station TYCM1 -1 (Section 5.5.3 of Progress Energy 2005b). If no power
generation occurred, DO concentrations were typically above 4.0 mg /L for 8 -12 hours
(Figure 6 -5 and Progress Energy 2005b,2006c, 2010). During power generation days, the period
of DO concentrations above 5.0 mg/L would be shorter, and DO concentrations would decline
below 4.0 mg/L during power generation.
6 -10

Section 6 2010 Water Quality Results
12.0
10.0
5 8.0
C 6.0
5C 4.0
IX
A
2.0
0.0
I A i L I
1ff1m�1'imln
oil
�Ll_L1W��
0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00
Time
20,000
16,000
12,000
8,000
A
4,000
0
TYCMl -1 TYCMl -2 TYCMl -3 TYCM2 Power Plant Generation Flow
Figure 6 -6 Dissolved oxygen concentrations (mg/L) and power plant generation flow
from July 6 to July 12 at Stations TYCM1 -1, TYCM1 -2, TYCM1 -3 and
TYCM2.
Even on days when no power generation occurred, the DO concentrations were not always high
enough to meet both North Carolina DO water quality standards at Stations TYCM1 -1 and
TYCM1 -2 in early August (Table 6 -3). From May 1 to October 31, the number of days without
any power generation during a 24 -hour period at the Tillery Hydroelectric Plant totaled 2 days.
Of these 2 days, daily mean DO concentrations were less than 5.0 mg /L on 1 day at Station
TYCM1 -1. Instantaneous DO concentrations below 4.0 mg/L occurred on 1 day at Station
TYCM1 -1 and 1 day at Station TYCM1 -2 (Table 6 -3). These results indicated that algal
respiration, tributary inflow, and /or wicket gate leakage from the power plant influenced DO
dynamics during non - generation periods at Stations TYCM1 -1, TYCM1 -2, TYCM1 -3, and
TYCM2.
6 -11

Section 6 2010 Water Quality Results
Table 6 -3 Days that no power was generated at the Tillery Hydroelectric Plant and
assessments of dissolved oxygen concentrations at stations in Reach 1 to
determine if they met the North Carolina water quality standards for daily
average and instantaneous dissolved oxygen concentrations during 2010.+
Date
3 -July
2- October
Total
Reach 1 Stations
TYCMI -1 TYCMI -2
< 5.0 < 4.0 < 5.0 < 4.0
mg/L mg/L mg/L mg/L
X X
N /A¶ N /A¶
1 1 0
TYCMI -3
< 5.0 < 4.0
mg/L mg/L
TYCM2
< 5.0 < 4.0
mg/L mg/L
X N /A¶ N /A¶
N /A¶ N /A¶
1 0 0 0 0
'Days when the daily average DO was < 5.0 mg/L and days when an instantaneous DO concentration was
< 4.0 mg/L are denoted with an "X ". Days that the water quality standards were met are not marked.
¶ No data were recorded for the given time period due to instrumentation malfunction. See Appendix A table A -2.
6.1.4 Dissolved Oxygen — Blewett Falls Dam to Below Hitchcock Creek (Reach 2)
For the May through October study period, instantaneous DO concentrations ranged from 0.1 to
11.6 mg /L at the four monitoring stations in Reach 2 (Table 6 -4). Mean DO concentrations at
these stations within Reach 2 ranged from 5.7 to 6.3 mg/L for the May through October period
(Table 6 -4). Generally, DO concentrations at stations within Reach 1 decreased during May and
June; were lowest during July and August; and then increased during early September through
October (Figure 6 -6).
Weekly average DO concentrations were usually lowest at Stations BFCMIA and BFCM2A.
Generally, the weekly average DO concentrations differed by less than 3.0 mg/L among all
stations. Weekly average DO concentrations for all monitored stations followed a similar spatial
trend throughout the monitoring period with Stations BFCMIA and BFCM2A generally
differing by 1.0 to 2.0 mg/L from the other station (Figure 6 -7).
6 -12

Section 6 2010 Water Quality Results
Table 6 -4 Dissolved oxygen concentration summary for Reach 2 of the Pee Dee River
below the Blewett Falls Hydroelectric Plant, May 1 to October 31, 2010.
Reach 2 Stations
Dissolved Oxygen (DO) Variable BFCM1 BFCMIA BFCM2A
Mean DO (mg/L) +
6.3
5.9
5.7
Range of DO (mg/L)
2.5 -11.0
0.1 -11.6
0.1 -11.1
Percent of DO concentrations < 5.0 mg/L
15.0%
33.9%
31.3%
Percent of DO concentrations < 4.0 mg/L
2.9%
14.3%
12.2%
Percent of DO concentrations < 3.0 mg/L
0.1%
3.5%
3.3%
Percent of DO concentrations < 2.0 mg/L
N /A¶
1.0%
1.5%
Date of lowest DO concentration
27 -Jun
2 -Aug
20 -Sep
First DO concentration < 5.0 mg/L
6 -Jun
14 -Jun
11 -Jun
Last DO concentration < 5.0 mg/L
29 -Sep
30 -Sep
18 -Oct
First DO concentration < 4.0 mg/L
27 -Jun
15 -Jun
11 -Jun
Last DO concentration < 4.0 mg/L
28 -Aug
28 -Sep
29 -Sep
First DO concentration < 3.0 mg/L
27 -Jun
30 -Jun
27 -Jun
Last DO concentration < 3.0 mg/L
13 -Jul
20 -Sep
21 -Sep
First DO concentration < 2.0 mg/L
N /A¶
25 -Jul
13 -Jul
Last DO concentration < 2.0 mg/L
N /A¶
20 -Sep
21 -Sep
Longest duration of DO < 5.0 mg/L (hours)
43.75
66.75
66.25
Start of longest duration of DO < 5.0 mg/L
20 -Aug
17 -Aug
11 -Jul
'Mean of all measurements for the monitoring period of May 1 to October 31, 2010.
¶ Not Applicable.
Instantaneous DO concentrations below 5.0 (mg/L) were most frequent at Stations BFCMIA
(33.9 %) and BFCM2A (31.3 %) during May through October (Table 6 -4). Instantaneous DO
concentrations below 5.0 mg/L represented about 15 percent of the total number of
measurements at Station BFCM1 during this same period. The percentage of DO concentrations
below 4.0 mg/L were also greatest at Stations BFCMIA (14.3 %) and BFCM2A (12.2 %).
Frequency distributions indicated that Station BFCMIA and BFCM2A had more DO
concentrations below 3.0 mg/L and more DO concentrations greater than 9.0 mg/L (Figure 6 -8).
6 -13

Section 6 2010 Water Quality Results
Blewett Falls Reach 2 - 2010
10
9
8
J 7
E
6
as
5
O
4
0
N
D) 3
0
`:
1
0+----
05/01/10
EI
06/01/10 07/01/10 08/01/10 09 /01/10
Date
- ^ - BFCM1 El El El BFCM1A �� BFCM2
10/01/10 11/01/10
Figure 6 -7 Weekly mean dissolved oxygen concentrations at continuous monitor stations
in Reach 2 of the Pee Dee River below the Blewett Falls Hydroelectric Plant,
May 1 to October 31, 2010.
6 -14

Section 6 2010 Water Quality Results
Blemtt Falls Reach 2 - 2010
35
0
�, 25
c
m
v
L
020
a
a
15
Cr
W
L
U- 10
5
0
0 -1 1 -2 2-3 3-4 4-5 5-6 6 -7 7-8 8-9 9 -10 10 -11 11 -12
Dissolved Oxygen (mg/L)
BFCM1 �BFCM1A MBFCM2A
Figure 6 -8 Frequency distributions of dissolved oxygen concentrations at continuous
monitor stations in Reach 2 of the Pee Dee River below the Blewett Falls
Hydroelectric Plant, May 1 to October 31, 2010.
Instantaneous DO concentrations initially declined below 5.0 mg/L in Reach 2 on June 6 at
Station BFCM1 (Table 6 -4). Dissolved oxygen concentrations below 5.0 mg/L were recorded in
Reach 2 until October 18 at Stations BFCM2A (Table 6 -4).
The minimum DO concentration for Reach 2 was 0.1 mg/L at Stations BFCMIA and BFCM2A
on August 2 and September 20, respectively (Table 6 -4). The lowest DO concentrations at all
stations during the late July to mid September time frame. The longest duration (66.75 hours at
Station BFCMIA) of DO concentrations below 5.0 mg/L also occurred during this time period.
6 -15

Section 6 2010 Water Quality Results
6.1.5 North Carolina Water Quality Standards for DO in Reach 2
Dissolved oxygen concentrations at Reach 2 stations were below one or both North Carolina
water quality standards for 21 to 70 days from May through October, depending upon the station
(Table 6 -5). All four stations had instantaneous DO concentrations below 4.0 mg/L and daily
average DO concentrations below 5.0 mg/L during this period (Figure 6 -9). Daily average DO
concentrations were below the water quality standard for some days in Reach 2 from June 11 to
September 29. Dissolved oxygen concentrations below the instantaneous water quality standard
(4.0 mg/L) were recorded on some days in Reach 2 beginning June 11 and ending September 29.
Dissolved oxygen concentrations were below one or both water quality standards at Station
BFCM1 on 30 days, the fewest of any stations in Reach 2.
Table 6 -5 Assessments of daily dissolved oxygen concentrations from May 1 to October
31, 2010 at stations in Reach 2 of the Pee Dee River below the Blewett Falls
Hydroelectric Plant compared to the North Carolina dissolved oxygen water
quality standards.
North Carolina Water Quality Standard
BFCM1
Reach 2 Stations
BFCMIA BFCM2A
Daily average DO (5.0 mg/L)
Number of days not meeting standard
21
46
38
First day standard was not met
27 -Jun
30 -Jun
26 -Jun
Last day standard was not met
27 -Aug
29 -Sep
29 -Sep
Instantaneous DO (4.0 mg/L)
Number of days not meeting standard
26
56
67
First day standard was not met
27 -Jun
15 -Jun
11 -Jun
Last day standard was not met
28 -Aug
28 -Sep
29 -Sep
Number of days either standard was not met+
30
60
70
Number of days assessed¶
165¥
140¥
151¥
+The total number of days that one or both of the North Carolina water quality standards for daily average
(5.0 mg/L) and instantaneous (4.0 mg/L) DO concentrations were not met.
¶The number of days assessed was the total number of days from May 1 to October 31 when DO concentrations
were recorded for at least half of the day.
¥ Appendix A.
6 -16

Section 6 2010 Water Quality Results
Blevm t Falls Reach 2, Station BFCM1 - 2010
15
14
13
12
11
J 10
a�
9
a�
a� 8
a
x
O 7
v
a�
O
6
y
y 5
D
4
3
2
1
O
05(01/2010 06/01/2010 07/01/2010 06/01/2010 09/01/2010 10/01/2010
Date
Blewett Falls Reach 2, Station BFCM1A - 2010
15
14
13
12
11
J 10
a�
E
c
9
a>
a� 8
a
X
O 7
v
a>
� 6
0
0 5
4
3
2
1
O
11/01/2010
05(01/2010 06/01/2010 07/01/2010 08/01/2010 09/01/2010 10/01/2010 11/01/2010
Date
Figure 6 -9 Daily averages (black line) and ranges (vertical bars) of dissolved oxygen
concentrations at Stations BFCM1, BFCMIA, and BFCM2A in Reach 2 of
the Pee Dee River below the Blewett Falls Hydroelectric Plant, May 1 to
October 31, 2010.
6 -17

Section 6 2010 Water Quality Results
Blew-aft t Falls Reach 2, Station BFC3Vl2A - 2010
15
14
13
12
11
U 10
E
c
a�
u� a
a
x
O 7
v
a�
O
6
HJ
0 5
4
3 I� II
2
1
O
05/01/2010 06/01/2010 07/01/2010 Oa/01/2010 09/01/2010 10/01/2010 11/01/2010
Date
Figure 6 -9 (continued).
At Station BFCM1, both instantaneous and daily average water quality standards were not met
for 30 days between June 27 and August 28 (Table 6 -5 and Figure 6 -9). The daily average DO
concentration was below 5.0 mg/L on 21 days from June 27 to August 27. Instantaneous DO
concentrations were below 4.0 mg/L on 26 days between June 27 and August 28.
At Station BFCMIA, both instantaneous and daily average water quality standards were not met
for 60 days between June 15 and September 29. The daily average DO concentration was below
5.0 mg /L on 46 days from June 30 to September 29. Instantaneous DO concentrations were
below 4.0 mg/L on 56 days between June 15 and September 28 (Table 6 -5 and Figure 6 -9).
Dissolved oxygen concentrations were below the instantaneous and daily average water quality
standards on more days at Station BFCM2A than at any other Station in Reach 2. At Station
BFCM2A, the instantaneous water quality DO standard was not met on 70 days beginning on
June 11 and ending on September 29 (Table 6 -5 and Figure 6 -9). The daily average DO
concentration was below 5.0 mg/L on 38 days between June 26 and September 29.
Instantaneous DO concentrations were below 4.0 mg/L on 38 days between June 26 and
September 29.
6.1.6 Operational Effects of the Blewett Falls Hydroelectric Plant
Dissolved oxygen concentrations at Stations BFCM1, BFCMIA, and BFCM2A fluctuated
throughout the study period (Figures 6 -9 and 6 -10). The operation of Blewett Falls Plant
influenced DO concentrations in Reach 2 during periods of lake stratification (Figure 6 -10). An
examination of DO concentrations and generation flows from July 6 -12 showed a distinct DO
cycle at all stations with power plant generation. Blewett Falls Plant operations have an effect
on DO levels in Reach 2, but the effect is dependent upon the degree of lake stratification
(Figure 5 -7), and the amount of water released from the plant.
6 -18

Section 6 2010 Water Quality Results
12.0
10.0
P
= 8.0
bA
C 6.0
4.0
0
IX
A 2.0
0.0
0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00
Time
BFCMl BFCMIA BFCM2A Power Plant Generation Flow
12,000
10,000
8,000
6,000
4,000
2,000
0
Figure 6 -10 Dissolved oxygen concentrations at Stations BFCM1, BFCMIA, and
BFCM2A, and power plant generation at the Blewett Falls Hydroelectric
Plant, July 6 to 12, 2010.
6.1.7 Comparison of DO Temporal Trends, 2004 - 2010
A comparison was made between temporal and spatial trends observed in DO concentrations in
each power plant tailwaters between the 2004 -2010 monitoring programs. Although the
monitoring period duration and station locations differed between years (i.e., May- November in
2004 and May- October in 2005- 2010), some general trends can be described relative to DO
concentrations in power plant tailwaters.
Generally, the means and ranges of DO concentrations were similar although there were some
differences in the lower end of measured DO concentrations depending upon station location
(Table 6 -6). The period that DO concentrations did not meet the water quality standards
occurred later in the year during 2007 from two to four weeks (i.e., mid May to early October)
compared to the period documented in other years (i.e., late May through early September). This
temporal difference was attributed to climatological differences, reservoir stratification patterns,
and subsequent power plant generation. The year 2007 was marked by a dry, warm spring and
hot summer. There were a greater percentage of DO values that were in the 2 -5 mg/L range in
2010 compared to other years at most continuous monitoring stations in both river reaches. The
May- October 2010 monitoring was climatologically described as warmer and drier than the 72-
year average (Figure 5 -1 and 5 -2).
Generally, spatial trends in both river reaches were consistent between monitoring years. The
stations closest to the Tillery Hydroelectric Plant have the greatest occurrence of DO values
below the DO water quality standards with the frequency of occurrence of low DO values
decreasing with increasing downstream distance. At the Blewett Falls Hydroelectric Plant, the
stations closest to the plant have the lowest occurrence of DO values below the DO water quality
standards, with the frequency of occurrence of low DO values increasing with increasing
downstream distance.
6 -19
U
bA
S.
U
IX

Section 6 2010 Water Quality Results
Table 6 -6 Comparison of DO summary statistics between the 2004 -2010 continuous
monitoring programs for the Tillery and the Blewett Falls Hydroelectric
Plants.
Tillery Hydroelectric Plant
Dissolved Oxygen (DO) Variable
Reach 1 Station
TYCMI -1
2004
2005
2006
2007
2008
2009
2010
Mean DO (mg/L)
5.3
5.4
5.4
5.2
5.1
5.2
4.6
Range of DO (mg/L)
1.2 -11.1
0.4 -13.1
0.9 -13.8
0.2 -14.0
0.6 -12.6
0.1 -12.3
0.2 -12.1
Percent of DO concentrations < 5.0 mg/L
42.5%
45.7%
46.8%
50.8%
47.1%
43.7%
56.3%
Percent of DO concentrations < 4.0 m
28.8%
31.3%
34.6%
37.9%
37.7%
30.8%
46.1%
Percent of DO concentrations < 3.0 mg/L
8.7%
14.4%
21.9%
27.6%
24.6%
21.4%
29.0%
Percent of DO concentrations < 2.0 m
0.5%
1.3%
6.3%
10.3%
3.3%
13.4%
11.8%
Daily average DO (5.0 mg/L)
Number of days not meeting standard
80
45
94
29
38
76
Number of days not meeting standard
83
76
81
91
79
70
90
First day standard was not met
June 3
June 30
10 -Jun
29 -Ma
12 -Jun
25 -Jun
17 -Jun
Last day standard was not met
Sep 7
Oct 7
14 -Sep
22 -Oct
8 -Oct
27 -Sep
23 -Sep
Instantaneous DO (4.0 mg/L)
93
94
128
First day standard was not met
12 -Jun
5 -May
30 -May
Number of days not meeting standard
91
87
97
115
94
68
90
First day standard was not met
June 1
June 10
25 -May
26 -May
30 -May
27 -Jun
26 -May
Last day standard was not met
Sep 8
Oct 7
14 -Se
19 -Oct
11 -Se
27 -Se
23 -Se
Number of days either standard was not
met'
94
88
98
117
95
74
91
Number of days assessed
1 140
1 169
1 195
1 214
1 161
168
1 146
Dissolved Oxygen (DO) Variable
Reach 1 Stations
TYCM1 -2
TYCM1 -3
2008
2009
2010
2008
2009
2010
Mean DO (mg/L)
4.7
5.6
4.8
5.8
5.9
5.5
Range of DO (mg/L)
1.2 -11.6
1.4 -13.8
1.4 -14.7
1.1 -14.4
0.9 -15.8
1.2 -17.2
Percent of DO concentrations < 5.0 mg/L
62.5%
41.7%
57.1%
47.0%
39.5%
50.7%
Percent of DO concentrations < 4.0 m
50.8%
27.5%
41.9%
37.4%
28.1%
37.1%
Percent of DO concentrations < 3.0 m
31.3%
16.8%
19.5%
18.2%
15.8%
18.7%
Percent of DO concentrations < 2.0 mg/L
5.5%
6.3%
3.5%
2.6%
3.3%
1.9%
Daily average DO (5.0 mg/L)
Number of days not meeting standard
80
45
94
29
38
76
First day standard was not met
12 -Jun
30 -Jun
6 -Jun
23 -Jun
2 -Jul
9 -Jun
Last day standard was not met
17 -Se
28 -Se
29 -Se
15 -Se
21 -Se
29 -Se
Instantaneous DO (4.0 mg/L)
Number of days not meeting standard
91
70
119
93
94
128
First day standard was not met
12 -Jun
5 -May
30 -May
12 -Jun
5 -May
1 -May
Last day standard was not met
21 -Se
28 -Se
14 -Oct
23 -Se
25 -Se
15 -Oct
Number of days either standard was not met+
91
70
119
93
94
128
Number of days assessed
110
143
1 154
1 I 3 4-1
165
1 172
6 -20

Section 6 2010 Water Quality Results
Table 6 -6 (continued).
Dissolved Oxygen (DO) Variable
Reach 1 Station
TYCM2
2004
2005
2006
2007
2008
2009
2010
Mean DO (mg/L)
6.7
6.8
7.2
6.9
6.8
6.2
6.4
Range of DO (mg/L)
2.1 -16.9
0.9 -17.7
1.8 -17.5
1.8 -17.0
1.8 -17.1
0.5 -18.7
1.8 -17.2
Percent of DO concentrations < 5.0 m
24.1%
32.3%
29.8%
37.6%
35.9%
36.1%
44.3%
Percent of DO concentrations < 4.0 mg/L
8.0%
20.3%
15.5%
25.3%
17.3%
22.4%
29.3%
Percent of DO concentrations < 3.0 m
0.6%
5.6%
5.1%
8.8%
2.8%
7.0%
5.2%
Percent of DO concentrations < 2.0 mg/L
0.0%
0.2%
0.2%
0.2%
0.1%
0.4%
0.1%
Daily average DO (5.0 mg/L)
Number of days not meeting standard
23
38
22
14
10
27
27
First day standard was not met
June 10
July 5
28 -Jun
25 -Jun
26 -Jun
1 -Jul
18 -Jun
Last day standard was not met
Aug 13
Aug 30
15 -Se
13 -Se
14 -Se
31 -Au
28 -Au
Instantaneous DO (4.0 mg/L)
Number of days not meeting standard
52
69
56
99
77
59
74
First day standard was not met
May 23
June 12
25 -Jun
27 -Ma
7 -Jun
21 -Jun
16 -Jun
Last day standard was not met
Sep 8
Sep 28
15 -Sep
19 -Sep
18 -Sep
21 -Sep
7 -Sep
Number of days either standard was not
met'
53
70
59
99
78
59
74
Number of days assessed
145
1 169
1 193
1 214
1 169
1 169
1 123
Blewett Falls Hydroelectric Plant
Dissolved Oxygen (DO) Variable
Reach 2 Station
BFCMI
2004
2005
2006
2007
2008
2009
2010
Mean DO (mg/L)
6.7
6.4
6.3
6.2
5.8
6.4
6.3
Range of DO (mg/L)
2.1 -11.5
2.5 -10.7
1.5 -11.8
1.4 -11.5
0.2 -10.7
1.0 -11.6
2.5 -11.0
Percent of DO concentrations < 5.0 mg/L
7.1%
16.3%
20.3%
24.9%
32.0%
18.4%
15.0%
Percent of DO concentrations < 4.0 mg/L
0.9%
2.4%
7.3%
9.5%
16.8%
6.3%
2.9%
Percent of DO concentrations < 3.0 mg/L
0.2%
<0.1%
1.1%
1.7%
7.8%
1.3%
0.1%
Percent of DO concentrations < 2.0 mg/L
0.0%
0.0%
0.2%
0.1%
3.2%
0.1%
0.0%
Daily average DO (5.0 mg/L)
Number of days not meeting standard
7
21
38
52
57
26
21
First day standard was not met
June 14
July 1
12 -Jun
11 -Jun
7 -Jun
5 -Jul
27 -Jun
Last day standard was not met
Sept 2
Oct 3
19 -Sep
26 -Sep
14 -Sep
24 -Sep
27 -Aug
Instantaneous DO (4.0 mg/L)
Number of days not meeting standard
12
27
40
67
71
36
26
First day standard was not met
May 31
June 26
10 -Jun
1 -Jun
3 -Jun
16 -Jun
27 -Jun
Last day standard was not met
Sept 6
Oct 3
20 -Sep
11 -Oct
14 -Sep
24 -Sep
28 -Aug
Number of days either standard was not
met'
12
33
47
71
75
39
30
Number of days assessed
141
1 183
1 192
1 202
177
1 163
1 165
6 -21

Section 6 2010 Water Quality Results
Table 6 -6 (continued).
Dissolved Oxygen (DO) Variable
Reach 2 Station
BFCMIA
2004
2005
2006
2007
2008
2009
2010
Mean DO (mg/L)
6.6
5.8
5.9
5.9
5.0
5.9
5.9
Range of DO (mg/L)
2.5 -10.0
0.3 -11.6
0.1 -11.7
0.5 -13.5
0.1 -10.2
0.7 -11.1
0.1 -11.6
Percent of DO concentrations < 5.0 mg/L
12.0%
33.3%
33.0%
38.4%
46.5%
26.9%
33.9%
Percent of DO concentrations < 4.0 mg/L
3.2%
13.6%
17.2%
16.6%
30.9%
12.9%
14.3%
Percent of DO concentrations < 3.0 mg/L
0.2%
4.6%
6.7%
6.2%
17.0%
4.3%
3.5%
Percent of DO concentrations < 2.0 mg/L
0.0%
1.8%
3.2%
1.7%
10.4%
0.8%
1.0%
Daily average DO (5.0 mg/L)
8 -Oct
27 -Se
29 -Se
Number of days either standard was not met+
93
67
70
Number of days not meeting standard
11
54
63
58
90
45
46
First day standard was not met
Jul 30
May 30
1 -Jun
29 -Ma
23 -Ma
26 -Jun
30 -Jun
Last day standard was not met
Sept 6
Oct 5
9 -Sep
12 -Sep
20 -Sep
24 -Sep
29 -Sep
Instantaneous DO (4.0 mg/L)
Number of days not meeting standard
23
58
89
92
104
61
56
First day standard was not met
July 30
June 6
23 -May
29 -May
6 -May
26 -Jun
15 -Jun
Last day standard was not met
Sept 6
Oct 5
13 -Se
16 -Oct
17 -Se
24 -Se
28 -Se
Number of days either standard was not met+
23
66
91
93
105
63
60
Number of days assessed
63
164
217
214
175
176
140
Dissolved Oxygen (DO) Variable
Reach 2 Station
BFCM2A
2008
2009
2010
Mean DO (mg/L)
5.1
5.5
5.7
Range of DO (mg/L)
0.2 -10.8
0.1 -10.3
0.1 -11.1
Percent of DO concentrations < 5.0 mg/L
48.2%
34.5%
31.3%
Percent of DO concentrations < 4.0 m
31.0%
22.4%
12.2%
Percent of DO concentrations < 3.0 m
16.1%
14.4%
3.3%
Percent of DO concentrations < 2.0 mg/L
8.1%
8.1%
1.5%
Daily average DO (5.0 mg/L)
Number of days not meeting standard
72
51
38
First day standard was not met
12 -Jun
29 -Jun
26 -Jun
Last day standard was not met
23 -Se
27 -Se
29 -Se
Instantaneous DO (4.0 mg/L)
Number of days not meeting standard
90
66
67
First day standard was not met
12 -Jun
26 -Jun
11 -Jun
Last day standard was not met
8 -Oct
27 -Se
29 -Se
Number of days either standard was not met+
93
67
70
Number of days assessed
136
152
151
+The total number of days that one or both of the North Carolina water quality standards for daily average
(5.0 mg/L) and instantaneous (4.0 mg/L) DO concentrations were not met.
¶The number of days assessed was the total number of days from May 1 to October 31 when DO concentrations
were recorded for at least half of the day.
"Station BFCMIA was added to the monitoring program on July 29, 2004.
§ Stations TYCM3, TYCM4, BFCM2, and BFCM3 were removed from the monitoring program on June 11, 2008.
"Stations TYCM1 -2, TYCM1 -3, and BFCM2A were added to the monitoring program on June 12, 2008.
6 -22

Section 6 2010 Water Quality Results
6.2 Water Temperature in the Pee Dee River
6.2.1 Reach 1- Tillery Dam to Turkey Top Creek
Water temperatures ranged from 14.3 °C to 37.8 °C in Reach 1 from May through October
(Table 6 -7). Mean water temperatures in Reach 1 from May through October ranged from
24.3 °C at Station TYCM1 -3 to 25.3 °C at Station TYCM2 (Table 6 -7). The Reach 1 maximum
instantaneous temperature of 37.8 °C occurred at Station TYCM1 -3 on July 24. Weekly mean
temperatures were slightly lower at Station TYCM1 -1 than the other stations from May through
early August, and Station TYCM1 -3 had slightly lower weekly mean temperatures from mid
August through October (Figure 6 -11).
Table 6 -7 Summary statistics of water quality variables from stations in Reach 1 of the
Pee Dee River below the Tillery Hydroelectric Plant, May 1 to October 31,
2010.
Water Quality Variable
TYCM1 -1
Reach 1 Stations
TYCM1 -2 TYCM1 -3
TYCM2
Mean temperature ( °C)
24.7
25.0
24.3
25.3
Temperature range ( °C)
16.4-30.8
15.8-34.0
14.3 -37.8
16.7-34.5
Median pH
6.8
6.8
6.9
6.9
pH range
6.5 -8.6
6.3 -9.3
6.3 -9.9
6.3 -10.1
Mean specific conductance (p S /cm)
90.9
91.7
88.9
89.6
Specific conductance range (pS /cm)
67.0-117.0
74.0-104.0
69.0-105.0
71.0-107.0
6 -23

Section 6 2010 Water Quality Results
Tillery Reach 1 - 2010
X
d
a0
d
20
U
Cn
cD
P
ED
cD
R
cD
10
a�
CL
E
a�
H
0i
05/01/10
06✓01 /10 07101110 08✓01 /10 09/01/10 10/01/10
Date
eee TYCM1 -1 �Q TYCM1 -2 TYCM1 -3 TYCM2
11/01/10
Figure 6 -11 Weekly mean temperatures at continuous monitor stations in Reach 1 of the
Pee Dee River below the Tillery Hydroelectric Plant, May 1 to October 31,
2010.
Temperature values greater than the North Carolina water quality standard of 32 °C were most
often observed at Station TYCM2 during July and August. Infrequent excursions above 32 °C
were noted at Stations TYCM1 -2 and TYCM1 -3. Temperature measurements greater than 32 °C
at Station TYCM2 accounted for less than 2 percent (n =221) of the total number of discrete
temperature measurements at this station (n= 11,232). There were 248 measurements greater
than 32 °C at Station TYCM1 -3 (n= 16,032) and 68 water temperature measurements greater than
32 °C at Station TYCM1 -2 (n= 13,824).
6.2.2 Reach 2 — Blewett Falls Dam to Below Hitchcock Creek
Water temperatures ranged from 17. VC to 35.8 °C at all stations in Reach 2 from May through
October in Reach 2 (Table 6 -8). Mean water temperatures in Reach 2 ranged from 25.7 °C at
BFCMIA to 26.3 °C at Station BFCM2A (Table 6 -8). The Reach 2 maximum instantaneous
temperature of 35.8 °C occurred at Station BFCMIA on July 4.
Weekly average water temperatures at all three stations were very similar throughout the study
period (Figure 6 -12).
6 -24

Section 6 2010 Water Quality Results
Table 6 -8 Summary statistics of water quality variables from stations in Reach 2 of the
Pee Dee River below the Blewett Falls Hydroelectric Plant, May 1 to October
31, 2010.
Reach 2 Stations
Water Quality Variable
BFCM1
BFCMIA
BFCM2A
Mean temperature ( °C)
26.2
25.7
26.3
Temperature range ( °C)
18.2-31.6
17.1-35.8
18.1-32.5
Median pH
7.0
7.1
7.0
pH range
6.5 -9.3
6.7 -9.3
6.5 -9.2
Mean specific conductance (pS /cm)
101.3
103.2
104.9
Specific conductance range (pS /cm)
73.0- 135.0
77.0-139.0
74.0-132.0
40
a�
L
30
U
N
L M
W
Co
L
C.
L
N
E 10
N
H
0 i
05(01/10
Blewett Fal Is Reach 2 - 2010
06101 /10 07101110 08101 /10 09/01/10 10101/10
Date
s e e BFCM1 E]--� BFCM1A , 6 BFCM2
11/01/10
Figure 6 -12 Weekly mean temperatures at continuous monitor stations in Reach 2 of the
Pee Dee River below the Blewett Falls Hydroelectric Plant, May 1 to October
31, 2010.
6 -25

Section 6 2010 Water Quality Results
Temperature values greater than the North Carolina water quality standard of 32 °C were most
often observed at Station BFCMIA during July and August. Infrequent excursions above 32 °C
were also noted at Station BFCM2A. Temperature measurements greater than 32 °C at Station
BFCMIA accounted for less than 1% (n =62) of the total number of discrete measurements at this
station (n= 13,920). There was one measurement >32 °C at Station BFCM2A (n = 13,726).
6.3 pH in the Pee Dee River
6.3.1 Reach 1— Tillery Dam to Turkey Top Creek
Median pH values at stations in Reach 1 were slightly acidic (6.8 to 6.9) for the study period
(Table 6 -7). Instantaneous pH values in Reach 1 ranged from 6.3 at Stations TYCM1 -2 and
TYCM1 -3 and TYCM 2 to 10.1 at Station TYCM2. Weekly mean pH means ranged from 6.7
to 7.7 at all stations (Figure 6 -13). Station TYCM1 -1 typically had the lowest weekly mean pH
values while Station TYCM2 usually had the highest weekly mean pH values. All stations
exhibited similar weekly mean pH trends during the monitoring period.
8
7
= 6
CL
6
41
05/01/10
Tillery Reach 1 - 2010
06/01/10 07101110 08✓01 /10 09/01/10 10f01/10
Date
eea TYC M1 -1 �Q TYC M1 -2 TYC M1 -3 M M TYCM2
11/01/10
Figure 6 -13 Weekly mean pH values at continuous monitor stations in Reach 1 of the Pee
Dee River below the Tillery Hydroelectric Plant, May 1 to October 31, 2010.
6 -26

Section 6 2010 Water Quality Results
The daily pH values fluctuated over a large range at Station TYCM2 and instantaneous values
frequently exceeded 9.0, particularly during May. These instantaneous pH values exceeded the
upper limit (9.0) of the North Carolina water quality standard for pH (NCDWQ 2007).
Approximately 4.2% of the total number of measurements (n= 11,232) at Station TYCM2
exceeded 9.0. Instantaneous pH values > 9.0 accounted for 2.2% (n =349) of the total number of
discrete measurements (n= 16,032) at Station TYCM1 -3. There were 13 measurements > 9.0 at
station TYCM1 -2 (n= 13,824). These pH fluctuations at Station TYCM2 followed DO trends;
reflect algal photosynthesis and respiration (Figure 6 -14). Algae produce oxygen and take up
carbon dioxide during photosynthesis, resulting in a pH increase. Conversely, when algae
respire and produce carbon dioxide, the pH decreases. Decreases in pH will also occur when
power plant generation flows release cooler /lower DO hypolimnetic water downstream with
lower pH values (Figure 6 -14).
20
16
12
i."
bA
YE 8
0
.O
7
O
IX
IX
A 4
20,000
16,000
12,000
w
U
_O
8,000
4,000
0 0
0:00 0:00 0:00 0:00 0:00 0:00 0:00 0:00 0:00
Time
Dissolved Oxygen (mg/1) pH Power Plant Generation Flow
Figure 6 -14 Dissolved oxygen concentrations, pH values, and power plant generation flow
at Station TYCM2 in Reach 1 of the Pee Dee River below the Tillery
Hydroelectric Plant, May 6 to 14, 2010.
6 -27

Section 6 2010 Water Quality Results
6.3.2 Reach 2 — Blewett Falls Dam to Below Hitchcock Creek
Median pH values at stations in Reach 2 were neutral (7.0 to 7.1) for the study period
(Table 6 -8). Instantaneous pH values in Reach 2 ranged from 6.5 at Stations BFCM1 and
13FCM2A to 9.3 at Stations BFCM1 and BFCMIA. Weekly mean pH values ranged from 6.8 to
7.8 (Figure 6 -15). Generally, Station BFCMIA had greater weekly mean pH values more often
than the other stations combined. All stations exhibited similar weekly mean pH trends during
the monitoring period (Table 6 -8).
s
7
= 6
CL
5
41
05101/10
Blewett Falls Reach 2 - 2010
06/01/10 07/01/10 08/01/10 09 /01/10 10(01/10 11/01/10
Date
see BFCM1 BFCM1A BFCM2
Figure 6 -15 Weekly mean pH values at continuous monitor stations in Reach 2 of the Pee
Dee River below the Blewett Falls Hydroelectric Plant, May 1 to October 31,
2010.
Variation in pH was greatest throughout Reach 2 from late August through September, which
coincided with a period of lower flow and warmer than average air temperatures. Less than 1%
of the total number of discrete pH values at all stations exceeded the North Carolina water
quality standard of 9.0.
6 -28

Section 6 2010 Water Quality Results
6.4 Specific Conductance in the Pee Dee River
6.4.1 Reach 1— Tillery Dam to Turkey Top Creek
Mean specific conductance values for stations within Reach 1 from May through October ranged
from 88.9 µS /cm at Station TYCM1 -3 to 91.7 µS /cm at Station TYCM1 -2 (Table 6 -7).
Instantaneous specific conductance values within Reach 1 ranged from 67 to 117 µS /cm.
Weekly mean specific conductance values were typically greater at Stations TYCM2
(Figure 6 -16).
120
110
v
N 100
v
co
90
v
0
80
U
v
70
CL
N
60
60+--
W01/10
Tillery Reach 1 - 2010
06 /01/10 07101110 08 /01/10 09/01/10 10f01 /10
Date
e �e TYC M1 -1 TYC M1 -2 �� TYC M1 -3 M - TYC M2
11/01/10
Figure 6 -16 Weekly mean specific conductance values at continuous monitor stations in
Reach 1 of the Pee Dee River below the Tillery Hydroelectric Plant, May 1 to
October 31, 2010.
6 -29

Section 6 2010 Water Quality Results
6.4.2 Reach 2 — Blewett Falls Dam to Below Hitchcock Creek
Mean specific conductance values at stations in Reach 2 ranged from 101.3 to 104.9 µS /cm for
the period from May through October (Table 6 -8). Instantaneous specific conductance values
ranged from 73 to 139 µS /cm. Weekly mean specific conductance values at each station
generally showed similar temporal trends during the study period (Figure 6 -17).
120
110
v
N 100
3
d
v
= 90
C9
v
3
= 80
0
U
2
70
CL
N
60
50
0501/10
Blewett Falls Reach 2 - 2010
06/01/10 07/01/10 08/01/10 09/01/10 10f01 /10
Date
eee BFCM1 El--� BFCM1A BFCM2
11/01/10
Figure 6 -17 Weekly mean specific conductance values at continuous monitor stations in
Reach 2 of the Pee Dee River below the Blewett Falls Hydroelectric Plant,
May 1 to October 31, 2010.
6 -30

Section 7 - Summary
This monitoring program assessed the spatial and temporal patterns of DO concentrations in the
Pee Dee River downstream of the Tillery and Blewett Falls Hydroelectric Plants using in -situ
continuous water quality monitors from May through October, 2010. The monitoring program
evaluated the longitudinal (upstream to downstream) and latitudinal (east bank to west bank)
differences in the DO regimes in the river associated with power plant operations over a seasonal
period of stratification and de- stratification of the Project reservoirs. The monitoring program
also evaluated spatial and temporal patterns of temperature, pH, and specific conductance in both
reaches below the power plants.
Continuous monitors were placed in the river below each power plant and within the sections
currently or previously designated by the NCDWQ under Section 303(d) of the Clean Water Act
as impaired due to low DO concentrations. The NCDWQ listed the 4.9 -mile reach from the
Tillery Dam to the Rocky River confluence. The 6.3 mile reach from the Blewett Falls Dam to
the mouth of Hitchcock Creek was previously listed as impared due to low DO concentrations.
Dissolved oxygen concentrations in the Pee Dee River from the Tillery Hydroelectric Plant to the
Rocky River confluence were below one or both water quality standards on some days from mid -
May to early October depending upon station location. This period corresponded with
stratification of the hypolimnion of Lake Tillery and the subsequent low DO concentrations of
lake water released during power plant generation into the river.
Dissolved oxygen concentrations generally increased throughout Reach 1 with increased distance
from the Tillery Hydroelectric Plant due to re- aeration in the river channel and tributary inflow.
Dissolved oxygen concentrations also generally increased from east river bank to west river bank
along the N.C. Highway 731 Bridge. Dissolved oxygen concentrations in Reach 1 were affected
by natural diel cycles of algal photosynthesis and respiration, tributary inflow, and power plant
generated flows. Dissolved oxygen concentrations usually increased during daylight hours and
decreased at night as a function of algal photosynthesis and respiration. Power plant generation
flow effects on DO dynamics were most evident when power generation occurred after DO
concentrations began to rise during the morning hours. Dissolved oxygen concentrations in the
river would decrease when the hypolimnetic water from Lake Tillery was released during power
generation. This effect was most evident at Station TYCM1 -1, located approximately 0.2 miles
downstream of the Tillery Plant.
Dissolved oxygen concentrations in Reach 1 were below the instantaneous and daily average DO
water quality standards on the day that the Tillery Hydroelectric Plant did not generate power.
Dissolved oxygen concentrations at Station TYCM1 -1 were below one or both water quality
standards on non -power generation days more than other stations in Reach 1.
Dissolved oxygen concentrations in the Pee Dee River below the Blewett Falls Hydroelectric
Plant were below one or both water quality standards on some days from mid -May to early
October. The period of lowest DO concentrations in Reach 2 also corresponded with stratified
DO conditions in Blewett Falls Lake when hypolimnetic DO concentrations were below
5.0 mg/L.
7 -1

Section 7 Summary
Dissolved oxygen concentrations did not increase throughout Reach 2 with increased distance
from the Blewett Falls Hydroelectric Plant. Both water quality standards were met more often at
Station BFCM1, the uppermost monitoring station nearest the power plant. The number of days
not meeting the water quality standards for DO concentrations and the percentage of DO
concentrations less than 5.0 mg/L were the greatest at Station BFCM2A, located approximately
2.1 miles downstream of the power plant.
The period that DO concentrations did not meet the water quality standards occurred later in the
year during 2010 in Reach 1 (i.e., early May through mid October) compared to the period
documented in other years (i.e., mid May through mid October). This temporal difference was
attributable to climatological differences, reservoir stratification patterns, and subsequent power
plant generation. The year 2010 was marked by a warm, dry spring and hot summer. However,
in all years, reservoir destratification and attainment of the state water quality standards occurred
by early to late September to mid October depending the annual climatological conditions,
reservoir inflow, and station location. Spatial trends in DO concentrations in the both river
reaches were similar during all years.
Water temperatures in both reaches corresponded to changes in ambient air temperatures and
precipitation. Weekly mean temperatures peaked during the mid to late August in Reach 1 and
peaked during late July in Reach 2. Temperatures were more consistent among stations within
Reach 2 over the study period due to the shorter length of the reach and fewer major tributaries
within Reach 2. Changes in water temperatures were minimal in both study reaches with the
arrival of hypolimnetic water released from the power plants.
The median pH values for stations in Reaches 1 and 2 were slightly acidic to near neutral (6.8 to
7.1). There was considerable temporal variation in weekly median pH values for both reaches.
This variability was mainly attributed to algal photosynthesis and respiration diel cycles. The
weekly mean pH values ranged from 6.7 to 7.7 in Reach 1, while weekly mean pH values ranged
from 6.8 to 7.8 in Reach 2. Station TYCM2 had periods of large daily fluctuations and high pH
values that likely resulted from algal photosynthesis and respiration cycles.
The mean specific conductance values for stations in Reaches 1 and 2 ranged from 88.9 to
104.9 uS /cm. At stations in Reach 1, mean specific conductance concentrations ranged from
88.9 to 91.7 uS /cm. Mean specific conductance values ranged from 101.3 to 104.9 US/cm in
Reach 2.
7 -2

Section 8 - References
North Carolina Division of Water Quality. 2006. North Carolina water quality assessment and
impaired waters list (2006 integrated 305(b) and 3030(d) list). Public review draft.
February 2006. North Carolina Department of Environment and Natural Resources,
Division of Water Quality, Raleigh, North Carolina.
2007. NC DENR- Division of Water Quality "Redbook." Surface waters and wetlands
standards. NC Administrative Code 15A NCAC 0213.0100, .0200 & .0300. Amended
effective: May 1, 2007. North Carolina Department of Environment and Natural
Resources, Division of Water Quality, Raleigh, North Carolina.
2008a. Yadkin -Pee Dee Project for Tillery and Blewett Falls Reservoirs. Rockingham,
Stanly, Anson, Richmond and Montgomery Counties. DWQ 02010437, Version 02.
Federal Energy Regulatory Commission Project Number 2206. APPROVAL of 401
Water Quality Certification Modified. North Carolina 401 Water Quality Certification,
Pages 11 -12. September 30, 2008.
2008b. Basinwide Water Quality Plans — Yadkin -Pee Dee River Basin. North Carolina
Department of Environment and Natural Resources, Division of Water Quality, Raleigh,
North Carolina.
2010. North Carolina water quality assessment and impaired waters list (2010 integrated
305(b) and 3030(d) list). EPA Approved. August 2010. North Carolina Department of
Environment and Natural Resources, Division of Water Quality, Raleigh, North Carolina.
Progress Energy. 2003. Initial consultation document. Yadkin -Pee Dee River Project FERC
No. 2206. February 2003. Progress Energy, Raleigh, NC.
2004. RWG meeting summary notes, templates, and study plans. Yadkin -Pee Dee River
Project FERC No. 2206. January 2004. Progress Energy.
2005a. Yadkin -Pee Dee River Project FERC No. 2206. Intensive temperature and
dissolved oxygen study of the Pee Dee River below the Tillery and Blewett Falls
Hydroelectric Plants. Water Resources Group. Issues Nos. 7 and 8 - Lake Tillery and
Blewett Falls Lakes and Tailwaters Water Quality. November 2005. Progress Energy.
2005b. Yadkin -Pee Dee River Project FERC No. 2206. Continuous water quality
monitoring in the Pee Dee River below the Tillery and Blewett Falls Hydroelectric
Plants. Water Resources Group. Issues Nos. 7 and 8 - Lake Tillery and Blewett Falls
Lakes and Tailwaters Water Quality. November 2005. Progress Energy.
2006a. Yadkin -Pee Dee River Project FERC No. 2206. Monthly water quality
monitoring study of Lake Tillery, Blewett Falls Lake, and associated tailwaters. Water
Resources Group. Issues Nos. 7 and 8 - Lake Tillery and Blewett Falls Lakes and
Tailwaters Water Quality. April 2006. Progress Energy. April 2006.
8 -1

Section 8
References
2006b. Application for license. Yadkin -Pee Dee River Project FERC No. 2206.
Submitted by Progress Energy, Raleigh, North Carolina.
2006c. Yadkin -Pee Dee River Hydroelectric Project FERC No. 2206. Continuous water
quality monitoring in the Pee Dee River below the Tillery and Blewett Falls
Hydroelectric Plants, May- October 2005.
2007a. Application for Water Quality Certification Pursuit to Section 401 (a) (1) of the
Clean Water Act. Yadkin -Pee Dee River Hydroelectric Project, FERC Project No. 2206.
Progress Energy Carolinas, INC., Raleigh, NC. May 2007.
2007b. Biology Program Procedures Manual (Procedures NR- 00058, NR- 00069, and
NR- 00071). Progress Energy Carolinas, Inc., Raleigh, North Carolina.
2007c. Biology Program Quality Assurance Manual. Progress Energy Carolinas, Inc.,
Raleigh, NC.
2008. Biology Program Procedures Manual (Procedures NR- 00071). Progress Energy
Carolinas, Inc., Raleigh, North Carolina.
2010. Yadkin -Pee Dee River Hydroelectric Project FERC No. 2206. Continuous water
quality monitoring in the Pee Dee River below the Tillery and Blewett Falls
Hydroelectric Plants, May- October 2006 -2009.
Southeast Regional Climate Center. 2011. Historic climate summaries for Wadesboro, NC
COOP Station 318964. http: / /www.dnr.state.sc.us. Columbia, South Carolina.
State Climate Office of North Carolina. 2011
Wadesboro, NC COOP Station 318964,
Carolina.
Precipitation and mean daily temperature for
http: / /www.nc- climate.ncsu.edu Raleigh, North
YSI. 2003. Environmental Monitoring Systems Operations Manual. YSI Incorporated. Yellow
Springs, Ohio.
8 -2

APPENDICES

APPENDIX A
SUMMARY OF CONTINUOUS MONITOR PERFORMANCE IN REACHES I AND 2 OF
THE PEE DEE RIVER BELOW THE TILLERY AND BLEWETT FALLS
HYDROELECTRIC PLANTS, 2010

Table A -1 Number and percentage of water quality parameter readings that were
recorded and retained for stations in Reaches 1 and 2 of the Pee Dee River
below the Tillery and Blewett Falls Hydroelectric Plants, May 1 to
October 31, 2010.
Number of Water Quality Parameter Readings
Specific
Station Temperature Dissolved Oxygen Conductance pH
Reach 1
TYCMI -1 14,112
13,132
14,112
14,112
TYCMI -2 13,824
13,824
13,824
13,824
TYCMI -3 16,032
15,648
16,032
16,032
TYCM2 11,232
11,232
11,232
11,232
Reach 2
BFCM1
14,880
14,880 14,880
14,880
BFCMIA
13,920
12,622 13,920
13,920
BFCM2A
13,728
13,155 13,728
13,728
100.0%
97.6%
Percentage of Water Quality Parameter Readings
100.0%
TYCM2
100.0%
Specific
100.0%
Station
Temperature
Dissolved Oxygen Conductance
pH
Reach 1
TYCMI -1
100.0%
93.1%
100.0%
100.0%
TYCM1 -2
100.0%
100.0%
100.0%
100.0%
TYCMI -3
100.0%
97.6%
100.0%
100.0%
TYCM2
100.0%
100.0%
100.0%
100.0%
Reach 2
BFCM1
100.0%
100.0%
100.0%
100.0%
BFCMIA
100.0%
90.7%
100.0%
100.0%
BFCM2A
100.0%
95.8%
100.0%
100.0%
Mean
100.0%
96.7%
100.0%
100.0%
Appendix A -1

Table A -2 Periods that water quality data were not recorded by YSI° 600XLM
continuous monitors or data were omitted upon review for stations in
Reaches 1 and 2 during 2010.
Station
Duration
Parameters
Affected+
Description
BFCMI
May 3 -May 18
Temp, DO,
Circuit board was declared bad by YSI Technician. All data
Sp Cond
declared invalid.
BFCMIA
May 18 -June 14
Temp, DO,
Meter was missing.
Sp Cond
BFCM2A
May 3 —May 18
Temp, DO,
Circuit board was declared bad by YSI Technician. All data
Sp Cond
declared invalid.
BFCM2A
May 18 —May 27
Temp, DO,
Hardware malfunction caused meter to go missing.
Sp Cond
BFCM2A
July 21 -July 27
DO
Hole in DO membrane.
TYCMI -1
June 28 -July 17
Temp, DO,
Battery/Power Pack was declared bad by YSI Technician.
Sp Cond
TYCMI -1
September 23-
DO
Low DO charge.
October 5
TYCMI -2
May 5 -May 28
Temp, DO,
Battery/Power Pack was declared bad by YSI Technician.
Sp Cond
TYCMI -3
October 11-
DO
Low DO charge.
October 14
TYCM2
July 20 -July 28
Temp, DO,
Monitor was stolen.
Sp Cond
TYCM2
September 7-
Temp, DO,
Monitor was stolen. This was the second meter declared
October 31
Sp Cond
stolen from this station. No data were collected at this station
after September 7
+Parameters monitored were temperature (Temp), dissolved oxygen (DO), pH, and specific conductance (sp Cond).
All represents all four monitored parameters.
Appendix A -2

Yadkin -Pee Dee Hydroelectric Project No. 2206
Tillery Hydroelectric Development
Dissolved Oxygen Enhancement Field Verification Methods for Tillery
Hydroelectric Development
Phase V -2011 Turbine Aeration Tests, Reservoir Oxygen Diffuser Tests, Crest Gate Minimum
Flow Tests, DO Compliance Monitor Tests, and Whole Plant Aeration Modeling Assessment
Prepared for Progress Energy Carolinas, Inc.
Prepared by
Richard J. Ruane, REMI
Mark H. Mobley, P.E., Mobley Engineering, Inc.
Charles W. Almquist, Ph.D., P.E., Principia Research Corporation
Paul Gantzer, Ph. D., P.E., GWRE, LLC
Jonathan C. Knight, Ph.D., REMI
Daniel F. McGinnis, Ph.D., MERC
Paul J. Wolff, Ph. D., WolffWare, Ltd.
111N
Mobley Engineering
December 2011
V PrQ0
AEO Rcscrvwr
Enxiroeirarerafar
fA3n.-Hff.menr, ra{

Table of Contents
Listof Figures ................................................................................... ............................... ............................iii
Listof Tables ................................................................................................................ ...............................
iv
ExecutiveSummary ....................................................................................................... ...............................
v
1.0 Introduction ........................................................................................................ ...............................
1
1.1 Site Description ............................................................................................... ..............................2
2.0 Turbine Aeration Tests ....................................................................................... ..............................4
2.1 Description of Units and Aeration Capabilities ............................................. ...............................
4
2.2 Test Methodology .......................................................................................... ...............................
5
2.2.1 Turbine Aeration Performance Tests ..................................................... ...............................
5
2.2.2 Tailrace DO Uptake Tests ....................................................................... ..............................6
2.3 Instrumentation .............................................................................................. ...............................
8
2.4 Analyses ......................................................................................................... .............................10
2.4.1 Air Flow ................................................................................................. .............................10
2.4.2 Relative Water Flow Rate .................................................................... ...............................
10
2.4.3 Turbine Efficiency ............................................................................... ...............................
10
2.5 Results ............................................................................................................ .............................11
2.5.1 Turbine Aeration Performance Tests ..................................................... .............................11
2.5.2 Tailrace DO Uptake Tests .................................................................... ...............................
12
2.5.3 Impact on Unit Efficiency ...................................................................... .............................13
3.0 Oxygen Diffuser Tests ..................................................................................... ...............................
27
3.1 Description of the Oxygen Diffuser ............................................................. ...............................
27
3.2 Diffuser Tests ................................................................................................. .............................28
3.2.1 Instrumentation .................................................................................... ...............................
28
3.3 Results ............................................................................................................ .............................29
3.4 Summary and Conclusions ........................................................................... ...............................
31
4.0 Crest Gate Operations ...................................................................................... ...............................
42
4.1 Test Procedure ............................................................................................. ...............................
42
4.2 Results ............................................................................................................ .............................42
5.0 Development and Calibration of the Tillery Turbine Aeration Model ............ ...............................
47
5.1 Background .................................................................................................. ...............................
47
5.2 Calibration Procedure .................................................................................. ...............................
47
5.3 Calibration Data and Results ........................................................................ ...............................
48
5.4 Summary and Conclusions ............................................................................. .............................49
6.0 Tillery System Aeration Model ....................................................................... ...............................
53
i

6.1 Background .................................................................................................... .............................53
6.1.1 Input Data ............................................................................................. ............................... 54
6.1.2 System Aeration Model Assumptions and Rules ................................. ............................... 54
6.2 Model Data and Results ............................................................................... ............................... 55
6.3 Summary and Conclusions ........................................................................... ............................... 56
7.0 Evaluation of Location of the Compliance Monitor ........................................ ............................... 61
8.0 Summary and Conclusions .............................................................................. ............................... 64
9.0 References .......................................................................................................... .............................66
ii

LIST OF FIGURES
Figure 1 -1. Location of the Yadkin -Pee Dee Hydroelectric Project, Tillery and Blewett Falls
Hydroelectric Developments ........................................................... ...............................
Figure 2 -1. Transverse Cross Section through Unit 1 ......................................... ...............................
Figure 2 -2. Tailrace Monitoring Stations for Turbine Venting Tests ................. ...............................
Figure 2 -3. 6 -inch Bellmouth Inlet for Units 1 - 3 (spoolpiece not shown) ....... ...............................
Figure 2 -4. 8 -inch Bellmouth Inlet for Unit 4 ..................................................... ...............................
Figure 2 -5. Unit 1 Air Flow vs. Power at Various Tailwater Elevations ............ ...............................
Figure 2 -6. Unit 2 Air Flow vs. Power at Various Tailwater Elevations ............ ...............................
Figure 2 -7. Unit 3 Air Flow vs. Power at Various Tailwater Elevations ............ ...............................
Figure 2 -8. Unit 4 Air Flow vs. Power at Various Tailwater Elevations ............ ...............................
Figure 2 -9. Unit 1 Air Flow and DO Uptake vs. Power Output ......................... ...............................
Figure 2 -10. Unit 2 Air Flow and DO Uptake vs. Power Output ....................... ...............................
Figure 2 -11. Unit 3 Air Flow and DO Uptake vs. Power Output ....................... ...............................
Figure 2 -12. Unit 4 Air Flow and DO Uptake vs. Power Output ....................... ...............................
Figure 2 -13. Unit 1 DO Uptake vs. Air:Water Ratio .......................................... ...............................
Figure 2 -14. Unit 2 DO Uptake vs. Air:Water Ratio .......................................... ...............................
Figure 2 -15. Unit 3 DO Uptake vs. Air:Water Ratio .......................................... ...............................
Figure 2 -16. Unit 4 DO Uptake vs. Air:Water Ratio .......................................... ...............................
Figure 2 -17. Effect of Air Admission on Unit Efficiency .................................. ...............................
Figure 3 -1. Schematic of an Oxygen Diffuser .................................................... ...............................
Figure 3 -2. Diffuser Layout and Reservoir Test Points ...................................... ...............................
Figure 3 -3. Tailrace Monitoring Stations for Oxygen Diffuser Tests ................. ...............................
Figure 3 -4. Turbine Operations and Tailrace DO Measurements 8/8/ 2011 ........ ...............................
Figure 3 -5. Turbine Operations and Tailrace DO Measurements 8/ 9/ 2011 ........ ...............................
Figure 3 -6. Turbine Operations and Tailrace DO Measurements 8/ 10/ 2011 ...... ...............................
Figure 3 -7. Turbine Operations and Tailrace DO Measurements 8/ 11/ 2011 ...... ...............................
Figure 3 -8. Turbine Operations and Tailrace DO Measurements 8/ 12/ 2011 ...... ...............................
Figure 3 -9. Lateral DO and Temperature Contours in Tillery Forebay 8/ 11/ 2011 ............................
Figure 3 -10. Longitudinal DO and Temperature Contours in Tillery Forebay 8/8/2011 ...................
Figure 3 -11. Longitudinal DO and Temperature Contours in Tillery Forebay 8/9/2011 ...................
Figure 3 -12. Longitudinal DO and Temperature Contours in Tillery Forebay 8/10/2011 .................
Figure 3 -13. Longitudinal DO and Temperature Contours in Tillery Forebay 8/11/2011 .................
Figure 3 -14. Longitudinal DO and Temperature Contours in Tillery Forebay 8/12/2011 .................
Figure4 -1. Tillery Crest Gate ............................................................................. ...............................
Figure 4 -2. Monitoring Stations for Crest Gate Tests ......................................... ...............................
Figure 4 -3. Tailrace Dissolved Oxygen and Crest Gate Operation, August 2011 .............................
Figure 4 -4. Tailrace Dissolved Oxygen and Crest Gate Operation for a Two Day Interval ..............
Figure 4 -5. Tailrace Dissolved Oxygen and Crest Gate Operation for a Three -Day Interval ...........
Figure 4 -6. Tailrace Dissolved Oxygen and Crest Gate Operation, August 2008 .............................
Figure 5 -1. Polynomial Fit for Tailwater Elevation vs Project Flow .................. ...............................
Figure 5 -2. Unit 1 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011 .............................................. ...............................
Figure 5 -3. Unit 2 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011 .............................................. ...............................
III
.. 3
.. 5
.. 7
..9
..9
14
14
15
15
16
16
17
17
18
18
19
19
20
27
28
29
35
35
36
36
37
37
38
38
39
39
40
43
44
45
45
46
46
49
49
..... 50

Figure 5 -4. Unit 3 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011 ................................................... ...............................
Figure 5 -5. Unit 4 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011 ................................................... ...............................
Figure 5 -6. DBM Calibration of Bubble Size versus Unit Flow Rate ..................... ...............................
Figure 5 -7. Turbine Aeration Model Predicted DO versus Measured DO .............. ...............................
Figure 6 -1. Project Flow Exceedance Plot for Tillery ............................................. ...............................
Figure 6 -2. Typical Input Data and Results for the System Aeration Model ........... ...............................
Figure 6 -3. Exceedance Plot of Diffuser Oxygen Flow Rate ................................... ...............................
Figure 6 -4. Hourly Exceedance Plot of the Predicted Project Discharge DO .......... ...............................
Figure 6 -5. Daily Average Exceedance Plot of the Predicted Project Discharge DO .............................
Figure 6 -6. Monthly Oxygen Requirements for the Diffuser .................................. ...............................
Figure 6 -7. Annual Oxygen Requirements for the Diffuser .................................... ...............................
Figure 7 -1. Lateral Variation of Tailrace Dissolved Oxygen and Crest Gate Operation ........................
Figure 7 -2. Lateral Variation of Tailrace Dissolved Oxygen and Crest Gate Operation, 8/10-
8/13/2011 ............................................................................................. ...............................
Figure 7 -3. Lateral Variation of Tailrace Dissolved Oxygen and Crest Gate Operation, 8/15-
8/18/2011 ............................................................................................. ...............................
LIST OF TABLES
Table2.1. Unit Characteristics ................................................................................. ...............................
Table 2.2. Instrumentation Used and Measured Parameters during Turbine Aerations Tests ................
Table 2.3. Nominal Power Settings (MW) for Aeration Performance Tests ........... ...............................
Table 2.4. Nominal Power Settings (MW) for Tailrace DO Uptake Tests .............. ...............................
Table 2.5. Unit 1 Turbine Aeration Tests ................................................................ ...............................
Table 2.6. Unit 2 Turbine Aeration Tests ................................................................ ...............................
Table 2.7. Unit 3 Turbine Aeration Tests ................................................................ ...............................
Table 2.8. Unit 4 Turbine Aeration Tests ................................................................ ...............................
Table 2.9. Unit 1 Tailrace DO Uptake Tests ............................................................ ...............................
Table 2.10. Unit 2 Tailrace DO Uptake Tests .......................................................... ...............................
Table 2.11. Unit 3 Tailrace DO Uptake Tests .......................................................... ...............................
Table 2.12. Unit 4 Tailrace DO Uptake Tests .......................................................... ...............................
Table 3.1. Oxygen Diffuser Test Matrix 8/8/ 2011 ................................................... ...............................
Table 3.2. Oxygen Diffuser Test Matrix 8/ 9/ 2011 ................................................... ...............................
Table 3.3. Oxygen Diffuser Test Matrix 8/ 10/ 2011 ................................................. ...............................
Table 3.4. Oxygen Diffuser Test Matrix 8/ 11/ 2011 ................................................. ...............................
Table 3.5. Oxygen Diffuser Test Matrix 8/ 12/ 2011 ................................................. ...............................
Table 3.6. Instantaneous Oxygen Demand and Biological Oxygen Demand Test Results ....................
Table 4.1. Crest Gate Design Parameters ................................................................ ...............................
lv
50
51
51
52
57
57
58
58
59
59
60
62
M
63
..4
.. 8
12
13
21
22
23
24
25
25
26
26
32
32
33
33
34
41
44

EXECUTIVE SUMMARY
Since 2005, Progress Energy Carolinas, Inc. has undertaken a comprehensive program to evaluate
technological methods for enhancing the dissolved oxygen (DO) concentrations at the Yadkin -Pee Dee
Hydroelectric Project No. 2206 (Tillery and Blewett Falls hydroelectric developments). This program
was undertaken to fulfill the DO Enhancement Plan that Progress Energy filed with the Federal Energy
Regulatory Commission and the North Carolina Division of Water Quality (NC DWQ) for complying
with North Carolina DO water quality standards by the end of 2011 (Progress Energy 2007; NC DWQ
2008).
In the summer of 2011, several DO projects were performed that included
1. Turbine aeration tests were performed to measure the air flow rates and DO uptake that turbine
venting provides for each unit.
2. A reservoir oxygen diffuser system was installed in the forebay of Lake Tillery that can provide a
maximum oxygen flow rate of 150 tons per day (151,000 scfh).
3. The oxygen diffuser system was tested for a five -day period on August 8th through the 12th to
investigate the performance of the system over a wide range of unit operations.
4. Minimum flow tests with crest gate releases were performed using the DO measured at the USGS
compliance monitor (NC Highway 731 Bridge).
5. A turbine aeration model was created to predict the quantity of air that a turbine can provide for a
given water flow rate and tailwater elevation and to predict the resulting DO increase for the
given air flow.
6. A system aeration model was created to evaluate the combined effect of turbine aeration, the
oxygen diffuser system operation, and crest gate and spill flow releases for achieving DO
compliance.
7. Lateral DO measurements across the width of the tailrace channel were acquired to determine the
spatial variations that occurred for various operating conditions and during various times of the
day.
As a result of the work performed in 2011, the following results were obtained:
1. The DO uptake for turbine aeration of Units 1 to 3 was measured and ranged from approximately
0.6 to 1.4 mg /L. Unit 4 achieved a significantly higher DO uptake of 2.7 mg/L, but only at low
power settings less than 10 MW. These results were similar to previous turbine aeration tests
conducted from 2007 to 2010.
Tests with the reservoir oxygen diffuser system demonstrated that it can provide the increase in
DO necessary during power plant generation to meet requirements as measured at the tailrace DO
compliance point located at the NC Highway 731 Bridge. On the first day of the test with no
oxygen flow from the diffuser and with turbine venting turned off, turbine flows produced a DO
that fell below 3.0 mg/L. By the third day of testing with sustained operation of the diffuser, the
DO at the compliance point was consistently 5.0 mg /L or higher. On the subsequent days of
testing, the DO periodically exceeded 6.0 mg /L.

A system aeration model predicted that both the minimum target of 4.0 mg /L and the daily
average target of 5.0 mg/L can be met in the discharge at the powerhouse.
Using the crest gate to provide minimum flows of 330 cfs is effective for achieving the target DO
of 4.0 mg /L at the compliance location. During non - generation periods in the early morning
hours, the DO dropped to 2.0 to 3.0 mg /L when the crest gate was not operated. When crest gate
flows were started within two hours after generation stopped, the target DO of 4.0 mg/L was
achieved.
However, as specified in the Project 401 Water Quality Certificate (NCDWQ 2008), it should be
noted that the 330 cfs minimum flow tested under these verification trials will not be required
until after the final and non - appealable FERC license has been issued for the Yadkin -Pee Dee
Hydroelectric Project, as well as for the upstream Yadkin Hydroelectric Project No. 2197. The
Yadkin Project flows are necessary to meet the minimum flows at the Yadkin -Pee Dee Project.
Under the existing minimum flow conditions of 40 cfs required in the current Yadkin -Pee Dee
Project license, the North Carolina water quality standards are not being met during the nighttime
hours when there is no power plant generation and aquatic plant respiration demands decrease
DO concentrations in the Project tailwaters.
The comparison of three lateral DO measurements at the NC Highway 731 Bridge showed
appreciable variation between them. Because the water flows more directly to the East Bank
under minimum flow conditions, the DO will be higher on this side of the tailrace due to the
shorter residence time and the reduced impact of the respiration effects for aquatic plants. For the
tests performed in this study, the DO measured near the East Bank consistently exceeded the
hourly minimum of 4.0 mg /L when the crest gate provided the minimum flow.
vi

1.0 INTRODUCTION
Since 2005, Progress Energy Carolinas, Inc. has undertaken a comprehensive program to evaluate
technological methods for enhancing the dissolved oxygen (DO) concentrations at the Yadkin -Pee Dee
Hydroelectric Project No. 2206 (Tillery and Blewett Falls Hydroelectric Developments). This program
was undertaken to fulfill the DO Enhancement Plan that Progress Energy filed with the Federal Energy
Regulatory Commission and the North Carolina Division of Water Quality (NC DWQ) for complying
with North Carolina DO water quality standards by the end of 2011 (Progress Energy 2007; NC DWQ
2008).
The methods and technologies evaluated include the following items:
Turbine Aeration with Passive Air Injection — The vacuum breaker was used for the air
passage. Initially the tests were performed without baffle plates and then baffle plates were added
to increase the passive air flow (DTA 2007, 2008; ARCADIS 2010a, 2010b; this report).
Turbine Aeration with Forced Air Injection — The air inlet locations for the forced air tests
included the vacuum breaker, draft tube vents, and through a ring that was fabricated for these
tests and installed at the top of the draft tube (DTA 2008; HDR -DTA 2009; ARCADIS 2010a,
2010b, 2010c).
Selective Withdrawal — These tests involved blocking off the lower section of the trashrack for
Unit 1 with canvas tarps. Tests were performed with the lower 20 and the lower 40 feet of the
trashrack blocked off (ARCADIS 2010a, 201Od).
Surface Water Mixing — These tests included testing an array of four smaller impellers and
testing a single large impeller (DTA 2008; HDR -DTA 2009).
Minimum Flow Releases Through the Crest Gate — These flows will generally be higher in
DO because reservoir surface water with higher DO is the source of the crest gate flow. In
addition, some aeration will occur as the water flows down the crest gate sluiceway (DTA 2008;
HDR -DTA 2009; ARCADIS 2010a, 2010b; this report).
Compressed Air Bubble Diffusers — This test involved placing a diffuser rack approximately
30 feet in front of the turbine intake and along the face of the intake screens. During unit
operation, compressed air was provided to the diffusers to aerate the water flowing into the
turbine (DTA 2008; HDR -DTA 2009; ARCADIS 2010a).
In the summer of 2011, additional DO verification testing was performed that included:
1. Turbine aeration tests were performed to measure the air flow rates and DO uptake that turbine
venting provides for each unit.
2. A reservoir oxygen diffuser system was installed in the forebay of Lake Tillery that can provide a
maximum oxygen flow rate of 150 tons per day (151,000 scfh).
3. The oxygen diffuser system was tested for a five -day period on August 8t' through the 12t'' to
investigate the performance of the system over a wide range of unit operations. On the first test
day, with the oxygen diffuser off and with no turbine venting, high generation flows produced
DO concentrations that were less than 3.0 mg /L at the mid - channel compliance point located at
the NC Highway 731 Bridge. During subsequent testing with diffuser operation and turbine

venting on, the DO consistently remained above 5.0 mg /L and periodically exceeded 6.0 mg /L at
the compliance point.
4. Minimum flow DO tests (330 cfs) with crest gate releases were performed for 24 -hour periods
using the USGS compliance monitor (NC Highway 731 Bridge).
5. A turbine aeration model was created to predict the quantity of air that a turbine can provide for a
given water flow rate and tailwater elevation and to predict the resulting DO increase for the
given air flow.
A system aeration model was created to evaluate the combined effect of turbine aeration, the
oxygen diffuser, and crest gate and spill flow releases for achieving DO compliance.
7. Lateral DO measurements across the width of the tailrace channel were acquired to determine the
spatial variations that occurred for various operating conditions and during various times of the
day.
In addition to the comprehensive DO testing program, Progress Energy has also conducted water quality -
related evaluations at the Tillery and Blewett Falls Developments since 2004 as part of the FERC
relicensing process and the NCDWQ 401 Water Quality Certification process for the Yadkin -Pee Dee
River Hydroelectric Project (FERC No. 2206), which includes both developments (Progress Energy
2005a, 2005b, 2006a, 2006b, 2006c, 2010, 2011). These evaluations have been conducted to address
temporal and spatial variations in seasonally low DO concentration levels in certain portions of the Pee
Dee River in the vicinity of each of the developments.
This report presents the results of the DO field verification tests performed during 2011 and the results of
system aeration modeling. The field tests and aeration modeling demonstrated that the Tillery
Development now has the capacity to attain the DO compliance requirements (i.e., instantaneous DO
value of 4.0 mg /L and daily DO average value of 5.0 mg /L) during power plant generation periods and
during nongeneration periods with a 330 cfs minimum flow.
1.1 Site Description
The Tillery Development is located on the Yadkin -Pee Dee River in Stanly and Montgomery counties in
south central North Carolina. The Tillery Development is part of the Yadkin -Pee Dee Hydroelectric
Project (FERC Project No. 2206), which also includes the downstream Blewett Falls Hydroelectric
Development. The Yadkin -Pee Dee Hydroelectric Project is owned and operated by Progress Energy
Carolinas, Inc. (PEC). The primary purpose of the Project is to provide peaking and load- following
generation. Total generating capacity of the hydroelectric plant is 86 MW. The Tillery Development
began operation in 1928 and is located at approximately mile 218 on the Pee Dee River in the Piedmont
region of North Carolina. Lake Tillery is the hydroelectric development's reservoir and has a normal
pool elevation of 277.3' feet above mean sea level.
'North American Vertical Datum of 1988 (NAVD 88). Unless otherwise noted, all data are NAVD 88.
The NAVD 88 is 0.9 ft lower than the 1929 National Geodetic Vertical Datum (NGVD 29).
2

Figure 1 -1. Location of the Yadkin -Pee Dee Hydroelectric Project, Tillery and Blewett Falls
Hydroelectric Developments.
Grten ur6
-CP Tu�MVw4
'
Ndmm Dam
-
Fac4 Dyne
horlott.•
Trl*ry Dam
9dewel! Falls Darn
Norm Camrrrra
50udh C &liiidlrF�
earrnr
vrrara
A f 1 a n I o c
0Caarr
a- �.ar.rw
r168S4 n— hl8rllti G75_i rlC�iDr!
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re a4F*larlM f.4L#1�1 � R/R
Figure 1 -1. Location of the Yadkin -Pee Dee Hydroelectric Project, Tillery and Blewett Falls
Hydroelectric Developments.

2.0 TURBINE AERATION TESTS
Field tests to characterize the ability of Units 1 — 4 to draw air into the draft tube and to assess the
resulting DO uptake in the tailrace were performed on August 2 -5, 2011. The objective of these tests was
to measure the air flow, other unit operating parameters, and the increase in tailrace elevation over a full
range of operating conditions. These results also provide calibration data for the "discrete bubble"
aeration model (DBM) used to predict the increase in DO at various operating conditions.
Data results from these tests are shown in the figures and tables located at the end of this section.
2.1 Description of Units and Aeration Capabilities
Table 2.1 summarizes some of the salient characteristics of the four generating units at the Tillery
Development. Figure 2 -1 shows a cross section through Unit 1.
Table 2.1. Unit Characteristics
Units 1 and 3 are of identical design, incorporating vertical -shaft Francis runners. Unit 2 is also a
vertical -shaft Francis runner of a slightly smaller design. The draft tubes of Units 1, 2, and 3 are of
identical design. As shown in Figure 2 -1, the draft tube is a Moody high -cone spreading design. The
draft tube has two vent lines to atmosphere: a six -inch line located high in the draft tube, which leads to a
valved bell -mouth inlet located just outside the wheel pit near the turbine pedestal; and a 10 -inch line
located low in the draft tube, the inlet of which enters the wheel pit just above the gate ring.
The 10 -inch line is located too low in the draft tube to effectively induce air flow. The 6 -inch line has
been shown in previous testing (ARCADIS 2010a, 2010b; DTA 2007) to induce measurable air flow
under some operating conditions. Previous testing has verified that little or no air flow is achieved
through several existing pipes leading into the headcover, even though the testing described here shows
that significant headcover vacuum exists under most operating conditions.
Unit 4 is a vertical shaft, axial -flow propeller design. Air admission to this unit is through an 8 -inch line
which enters the headcover, throttled by a gate -cam- controlled valve. The air inlet is a pipe end which
protrudes into a recess in the pedestal wall facing the dam. No drawings of the draft tube were available.
4
Unit 1
Unit 2
Unit 3
Unit 4
Rated Turbine Power (hp)
31,100
25,600
31,100
33,000
Best Efficiency Power (MW)
19
16
19
23
Maximum Power (MW)
21
18
21
27
Minimum Flow (cfs)
2,428
1,933
2,428
31603
Best Efficiency Flow
3,613
2818
3,613
4,230
Maximum Flow (cfs)
4,540
3,700
4,540
5,220
Units 1 and 3 are of identical design, incorporating vertical -shaft Francis runners. Unit 2 is also a
vertical -shaft Francis runner of a slightly smaller design. The draft tubes of Units 1, 2, and 3 are of
identical design. As shown in Figure 2 -1, the draft tube is a Moody high -cone spreading design. The
draft tube has two vent lines to atmosphere: a six -inch line located high in the draft tube, which leads to a
valved bell -mouth inlet located just outside the wheel pit near the turbine pedestal; and a 10 -inch line
located low in the draft tube, the inlet of which enters the wheel pit just above the gate ring.
The 10 -inch line is located too low in the draft tube to effectively induce air flow. The 6 -inch line has
been shown in previous testing (ARCADIS 2010a, 2010b; DTA 2007) to induce measurable air flow
under some operating conditions. Previous testing has verified that little or no air flow is achieved
through several existing pipes leading into the headcover, even though the testing described here shows
that significant headcover vacuum exists under most operating conditions.
Unit 4 is a vertical shaft, axial -flow propeller design. Air admission to this unit is through an 8 -inch line
which enters the headcover, throttled by a gate -cam- controlled valve. The air inlet is a pipe end which
protrudes into a recess in the pedestal wall facing the dam. No drawings of the draft tube were available.
4

lrlriLl
���I��1
A
Figure 2 -1. Transverse Cross Section through Unit 1
2.2 Test Methodology
Two types of aeration tests were performed on all units:
Turbine aeration performance, in which air flows and unit operating characteristics were
measured over a range of power outputs and tailwater elevations. These tests were run relatively
rapidly, with no DO measurements being made.
2. DO uptake measurement in the tailrace, run at one tailwater elevation and for sufficient time to
allow steady -state DO uptake measurements over a range of power outputs.
2.2.1 Turbine Aeration Performance Tests
The primary objective of the turbine aeration performance tests was to measure the naturally induced air
flow into the aeration vents of each of the four units over a range of power outputs and tailwater levels. A
secondary objective was to assess the effect of air admission on unit efficiency. For this objective,
relative water flow rate was to be determined by measuring the pressure difference between a raw water
line connected to the face of the dam and penstock piezometer taps located near the inlet to the spiral
case, the flow rate being proportional to the square root of this pressure difference. However, because
none of the penstock piezometer lines (4 per unit) on Units 1 — 3 were operational, relative flow rate
measurements were not possible for those units. The Unit 4 piezometers were functional.
Despite the lack of a direct relative flow rate measurement for Units 1 — 3, a method for estimating the
effect of air admission on efficiency was developed and is described in Section 2.4, Analyses.

Because air flow is generally strongly dependent on tailwater elevation, tests were conducted
simultaneously on two units. One unit started a test series at maximum power output, the other at
minimum power output, with the remaining two units either off or in condensing mode (i.e., at zero
discharge). The unit at maximum power output was stepped down in power at each test point, while the
unit at minimum power was correspondingly stepped up, until both had covered the range from minimum
to maximum power. This mode of testing kept the total discharge from the two units under test
approximately constant, so that the tailwater elevation also remained approximately constant. An
additional advantage was that the tests could be completed more quickly, since two units were tested
simultaneously.
At each test condition (i.e., at each power output), two runs were made: one with the air valves open, the
other with air valves closed. When moving to a new power output, the air valves were left at the position
they had been at for the previous test. A test run was made at the new power output, the air valve position
changed, a test run made at that condition, and continuing through the range of power outputs.
During testing, each unit was set to the desired power output and air valve position, and allowed to
stabilize for about two to three minutes. Data was acquired from all instruments (described in
Section 2.3, Instrumentation) at a rate of one complete scan every second for three minutes. Basic
analysis of the data was performed in near -real time, the results being made available as the units were
being set to the next power output.
At the conclusion of the first series of tests, one of the other two units was brought online at best
efficiency to increase the discharge and thus raise the tailwater elevation. After the tailwater elevation
had stabilized, the testing sequence described above was repeated. Following those tests, the remaining
unit was brought online and testing performed at the high tailwater elevation.
Because measurement of DO uptake was not an objective of these tests, a large number of test runs at
various power outputs and tailwater elevations was possible.
Units 2 and 4 were tested together, as were Units 1 and 3. One day of testing was required for each pair
of units at all three tailwater elevations.
2.2.2 Tailrace DO Uptake Tests
The objective of the tailrace DO uptake tests was to quantify the increase in DO attributable to turbine
venting for each of the four units. This information was used to calibrate the mathematical DO transfer
model (DBM or "Bubble Model"). All tests were run with only the unit being tested generating, so these
tests were performed at the lowest possible tailwater elevation.
A two - person field crew operating in a motorized inflatable boat in the tailrace obtained surface
measurements of temperature, DO, total dissolved gas (TDG), and conductivity in the tailrace
immediately downstream of the draft tube exit of the unit being tested. Locations of the tailrace
measurements are shown in Figure 2 -2. In addition, all of the unit parameters monitored during aeration
performance tests were also acquired during these tests.
Starting with the air valve closed, the tested unit was set to its minimum power output (minimum
discharge). Turbine parameters and the water quality parameters enumerated above were collected for a
period of approximately 15 minutes. This yielded the background DO concentrations at the set discharge.
The air valve was then turned on, flow conditions in the tailrace allowed to stabilize, and the turbine and
water quality parameters recorded.
Ce

The unit was set to successive power outputs, up to maximum power, with the air valve position at the
start of a test pair being the same as the end of the previous test pair.
Obtaining the "air -off' water quality data at each power output was necessary because the withdrawal
zone in the reservoir generally depends on the flow rate, which changes with each change in unit power.
The air -off tests were not possible for Unit 4 because of the cam - actuated air valve. However, air flow
only occurred over a very limited range of gate openings, so that the background DO of the first test made
after air valve closure can be expected to be representative of the background over the range of air
admission.
Turbine Venting Monitoring Points
Figure 2 -2. Tailrace Monitoring Stations for Turbine Venting Tests
7

2.3 Instrumentation
Table 2.2 lists the turbine parameters measured and instrumentation used in these tests.
Table 2.2. Instrumentation Used and Measured Parameters during Turbine Aerations Tests
Measurement
Location
Instrument
Model
Data Acquisition
Control room
Data acquisition system
HP 34970A
Headwater
Control room
Plant instrument
Tailwater
Control room
Plant instrument
Power
Control room
Plant instrument
Air pressure
Turbine floor
Absolute pressure cell
Rosemount 3051CA1
Air temperature
Turbine floor
RTD/RH combo
Omega HX91
Relative humidity
Gate position
Turbine floor
Wheel pit (U1— 3)
Gov. Cabinet (U4)
RTD/RH combo
Pullpot
Omega HX91
Celesco PT420 -40
Air flow
Air inlet
DP cell
Rosemount CD2
Headcover press
Wheel pit
GP cell
Rosemount CD3
Air flow was measured using the bellmouth inlets on all units. A 6 -inch draft tube air vent bellmouth
(used on Units 1 — 3) is shown in Figure 2 -3. For these tests, a short spool piece (not shown) with two
pressure taps was inserted between the bellmouth and the valve, allowing the bellmouth throat pressure to
be measured. The Unit 4 air inlet was located behind a grate, with a non - related valve body about a foot
in front of it. A custom - fabricated short body bellmouth with throat pressure taps was installed by
attaching the bellmouth to the protruding pipe with a rubber coupling. A photograph of the installation is
shown in Figure 2 -4.

Figure 2 -3. 6 -inch Bellmouth Inlet for Units 1— 3 (spoolpiece not shown)
Figure 2 -4. 8 -inch Bellmouth Inlet for Unit 4
m

2.4 Analyses
2.4.1 Air Flow
Air flow velocity V, was determined from the gage pressure measured at each bellmouth using a
simplified version of the air velocity calculation given in American Society of Mechanical Engineers
(1971):
Va = 66.75
where h is bellmouth pressure in inches of water. This equation is within about 3% of the full equation
for low Mach number flows at air temperatures between 40 and 100 °F.
The air flow rate Qa is computed from:
Qa = VA
where A is the bellmouth throat area in W.
2.4.2 Relative Water Flow Rate
For all units, the water flow rate for the air -off tests were taken from the plant's power- discharge tables
For an air -on test, a procedure was developed for estimating the change in flow rate from the
corresponding air -off test, as described below.
During these tests, the units were operated on automatic generation control, which meant that the unit was
computer - controlled to deliver a desired power output. At each test condition, the desired power output
was entered into the control system, which then moved the wicket gates to achieve the desired power
output. When the air valve position was changed, the presence or absence of air flow would cause a
change in power output (less power with air on), and the control system would move the gates to
compensate.
A curve of water flow rate Q versus gate opening G for each unit was developed from the air -off test data.
Using this curve and change in gate opening from the air -off to the air -on tests, the change in flow rate
was estimated. Although it might be expected the Q -G curve may itself change with air admission, that
change is likely to be small, so that calculations based on the small changes in gate experienced here
would not be affected significantly.
The effect on unit efficiency is discussed in Section 2.5, Results
2.4.3 Turbine Efficiency
Turbine efficiency q is defined by
P
= 737.6 PgQH
Where Pis the power output (kW), p is the water density (lbm /ft3), gis the acceleration of gravity (ft 2 /s),
Q is the water flow rate (ft3 /s), and His the gross head (ft, headwater elevation minus tailwater elevation).
10

2.5 Results
2.5.1 Turbine Aeration Performance Tests
The nominal test program for the aeration performance tests is shown in Table 2.3 below. Units 2 and 4
were tested together, as were Units 1 and 3.
Because the generating units were on automatic generation control, the target power outputs were not
exactly achieved, but the intended range of power outputs was covered.
The test data and computed results for the aeration performance tests are summarized in Tables 2.5 — 2.8,
located at the end of this section.
Figures 2 -5 through 2 -8 show the measured air flow for Units 1 — 4 as a function of power output at
tailwater elevations from about 205 to 209 ft (1929 NGVD, so values are 0.9 ft higher than the NAVD 88
datum). Air flows follow the same general trends as in previous tests, but are generally somewhat lower.
This difference maybe due to the different flow measurement techniques employed. The 2010 tests used
single -point velocity measurements for Units 1 — 3 and velocity traverses for Unit 4. The tests described
herein used bellmouth inlets for all air flow measurements.
The figures show that, in agreement with previous testing, Unit 4 provides the largest air flow; but only at
low gate openings below the normal operating range for this unit. The headcover pressure measurements
summarized in Table 2.8 show that the headcover pressure rises rapidly after the cam - operated valve
closes, indicating that no additional air flow would be achieved if the valve were disconnected from the
cam and allowed to stay open at higher power outputs.
Units 1 and 3 both achieve air flow at all tailwater elevations, with Unit 1 peaking at about 35 cfs at the
lowest tailwater elevation, and Unit 3 peaking at about 30 cfs. The best air flow appears to be achieved
near the most efficient power output (i.e., at "economy load ") for both units. Unit 1 generally exhibits air
flow at all power outputs, while Unit 3 does not aerate below about 15 MW.
11

Table 2.3. Nominal Power Settings (MW) for Aeration Performance Tests
Note: Each unit under test was operated with air on and air off.
August 4, 2011
August 2, 2011
Units under test
Tailwater
Condition
Unit 2
Unit 4
Unit 1
Unit 3
Low
Tailwater
Elevation
18
8
0
0
17
10
0
0
16
12
0
0
15
14
0
0
14
16
0
0
13
18
0
0
12
20
0
0
11
22
0
0
10
24
0
0
9
26
0
0
8
27
0
0
Mid
Tailwater
Elevation
8
27
0
18
10
24
0
18
12
20
0
18
14
16
0
18
16
12
0
18
18
18
0
18
High
Tailwater
Elevation
18
8
18
18
16
10
18
18
14
12
18
18
12
17
18
18
10
22
18
18
8
27
18
18
Note: Each unit under test was operated with air on and air off.
August 4, 2011
Units under test
Tailwater
Unit 1
Unit 3
Unit 2
Unit 4
21
9
0
0
20
10
0
0
18
11
0
0
17
12
0
0
16
14
0
0
15
15
0
0
14
16
0
0
12
17
0
0
11
18
0
0
10
20
0
0
9
21
0
0
9
21
0
24
12
18
0
24
14
16
0
24
16
14
0
24
18
12
0
24
21
9
0
24
21
9
16
24
18
12
16
24
16
14
16
24
14
16
16
24
12
18
16
24
9
21
16
24
Unit 2 is the least effective at inducing air flow, with essentially no air induced at the highest tailwater
elevation. At lower tailwater elevations, it generally induced air flow at power outputs above about 10
MW, but the peak air flow at the lowest tailwater elevation was only about 20 cfs.
2.5.2 Tailrace DO Uptake Tests
The nominal test program for the tailrace DO uptake tests is shown in Table 2.4. Test data and computed
results for these tests are summarized in Tables 2.9 — 2.12, located at the end of this section.
Figures 2 -9 through 2 -12 show the air flows and DO uptake measured during the tailrace tests. These
were all single -unit tests, so that the tailrace was at the lowest elevation, and air flows were at their
highest.
12

Table 2.4. Nominal Power Settings (MW) for Tailrace DO Uptake Tests
August 5, 2011
August 3, 2011
1045- 1245
1100- 1230
1345 - 1530
9
Unit 4
Unit 2
1.
8
8
2.
9
10
3.
10
12
4.
13
14
5.
18
16
6.
27
18
August 5, 2011
0730- 1000
1045- 1245
Unit 3
Unit 1
9
9
12
12
14
14
16
16
18
18
21
21
Notes: Only the unit under test was generating during these tests.
Units were operated with air on and air off at each test condition.
For Units 1 — 3, the DO uptake ranges from about 0.6 to 1.4 mg /L, with Unit 2 showing the poorest
performance in this regard. Unit 4 shows a substantially higher DO update at about 2.7 mg /L, but only at
very low power outputs. These results are similar to previous aeration tests conducted during 2006 to
2010 (DTA 2007, 2008; ARCADIS 2010a, 2010b).
Though there is scatter in the data, these graphs show that no apparent strong correlation exists between
air flow and DO uptake. This is further confirmed by Figures 2 -13 through 2 -16, which plot DO uptake
against air:water ratio. With the possible exception of Unit 3, the correlations are weak. The lack of
correlation of DO uptake with air:water ratio suggests that some factor other than air flow rate is limiting
the transfer of oxygen to the water.
One possibility for Units 1 — 3 is that, because the air enters at a single point on the side of the draft tube,
relatively little mixing of the air with the water flow occurs, so that the surface area over which oxygen
transfer can occur is limited. In this case, increasing air flow may not provide a commensurate increase in
transfer surface area available, with the consequence that the dependence of DO uptake on air flow or
air:water ratio is diminished.
2.5.3 Impact on Unit Efficiency
The impact of air admission on unit efficiency was estimated as previously described in Section 2.4,
Analyses. The result for Unit 1, which is typical, is shown in Figure 2 -17, where air:water ratio and
efficiency change are plotted as a function of water flow rate. The effect on efficiency is generally small,
with a trend toward larger losses at higher air:water flow ratios. At the highest discharges, the efficiency
loss is about 1.2 %, where the air:water ratio is about 0.6 %. This agrees with previous experience at
medium head plants (head between 60 and 150 feet), where the impact of air admission on efficiency is
generally found to be on the order of about 1% efficiency loss per 1% of air:water ratio.
13

35
30
25
20
V
3
0
LL
Q 15
10
5
■ N = 205.4
•N =206.5
•1w =ma.i
• N = 208.9
Tillery Unit 1
Air Flow
0
0 5 10 15 20
Power (KW
Figure 2 -5. Unit 1 Air Flow vs. Power at Various Tailwater Elevations
35
30
25
20
V
9
0
LL
Q 15
10
5
■N =205.0
•N =206.8
•N =208.0
• N = 208.9
Tillery Unit 2
Air Flow
0
0 5 10 15 20
Power (NMI
Figure 2 -6. Unit 2 Air Flow vs. Power at Various Tailwater Elevations
14
25
25

35
30
25
F20
V
3
0
LL
Q 15
10
5
■ N = 205.4
•N =206.5
♦N =208.1
• N = 208.9
Tillery Unit 3
Air Flow
0 AO
0 5 10 15 20
Power (NMI
Figure 2 -7. Unit 3 Air Flow vs. Power at Various Tailwater Elevations
90
80
70
60
y 50
3
0
LL
40
Q
30
20
10
0
■ ry = 205.4
• N = 06.8
• w =208.0
• N = 208.9
Tillery Unit 4
Air Flow
25
0 5 10 15 20 25 30
Power (NMI
Figure 2 -8. Unit 4 Air Flow vs. Power at Various Tailwater Elevations
15

Tillery Unit 1
35
30
25
20
v
3
O
LL
Q 15
10
5
0
0 5 10 15 20
Power (MVV)
Figure 2 -9. Unit 1 Air Flow and DO Uptake vs. Power Output
0 5 10 15 20
Power (MVV)
Figure 2 -10. Unit 2 Air Flow and DO Uptake vs. Power Output
L[:
1.4
1.2
1.0
0.8
w
Y
Q
7
0.6 0
D
0.4
0.2
- 0.0
25
1.4
1.2
W1,
0.8
d
R
Q
0.6 0
0
M
0.2
0.0
25

35
30
25
20
V
3
O
LL
Q 15
10
5
0
0 5 10 15 20
Power (MVV)
Figure 2 -11. Unit 3 Air Flow and DO Uptake vs. Power Output
Tillery Unit 3
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0 5 10 15 20 25
Power (NM
Figure 2 -12. Unit 4 Air Flow and DO Uptake vs. Power Output
17
1.4
1.2
if
0.8 E
d
Y
Q
7
0.6 0
0
Ai
0.2
0.0
25
5.0
4.0
3.0 c
E
Y
R
Q
2.0 0
1.0
0.0
30

2.0
1.5
w
1.0
Q
7
O
0
0.5
Tillery Unit 1
DO Uptake vs Air:Water Ratio
0.0
0.00 0.25 0.50
Air:Water Ratio (% )
Figure 2 -13. Unit 1 DO Uptake vs. Air:Water Ratio
PAI
1.5
E
w
� 1.0
7
O
D
0.5
Tillery Unit 2
0.75 1.00
DO Iptake vs Air:111
mmm
mmmmmmmmmmmmmmmmmmm
iii��■ii�iii� iii
0.00 0.25 0.50 0.75 1.00
Air:Water Ratio ( %)
Figure 2 -14. Unit 2 DO Uptake vs. Air:Water Ratio
18

2.0
1.5
w
1.0
Q
7
O
0
0.5
Tillery Unit 3
DO Uptake vs Air:Water Ratio
0.0
0.00 0.25 0.50
Air:Water Ratio (% )
Figure 2 -15. Unit 3 DO Uptake vs. Air:Water Ratio
5
4
c 3
w
Y
Q
O 2
0
1
Tillery Unit 4
z,*, sp mat o
0
0.0 0.5 1.0 1.5 2.0 2.5
Air:Water Ratio ( %)
Figure 2 -16. Unit 4 DO Uptake vs. Air:Water Ratio
19
0.75 1.00
3.0 3.5 4.0

1.0
0.5
Gl
0.0
Q
O
G1
O)
C
-0.5
U
a
U
C
Gl
U_
.w
W
-1.0
-1.5
Efficiency Change and Air:Water Ratio vs. Discharge
Unit 1 Tailwater206.5ft
• Efficiency change
■Air: Water ratio
500 1000 1500 2000 2500 3000 3500 4000 4500 5000
Discharge (cfs)
Figure 2 -17. Effect of Air Admission on Unit Efficiency
20

Table 2.5. Unit 1 Turbine Aeration Tests
Common Data I Unit 1 Data I Calculations
21
Head-
Flow
Air:
Test Con-
Air
Water
Air
Air
Re 1.
U1
U1 Gate
cover
U1 Air
Gate
for
Gross
Air Vel.
Air
Water
Unit Effic
Run
Time
dition
Valve
Temp
HW
TW
Press
Temp.
Humid.
Flow
U1 MW
Stroke
Press
Flow
Pos
Calcs
Head
ocity
Flow
Ratio
iency
EST
F
ft
ft
psia
F
%
cfs
MW
in
in H2O
in H2O
%
cfs
ft
We
cfs
13TOlN
9:59
Low TW
Off
83
277.94
206.35
14.59
91.01
59.28
4288
21.53
6.93
-95.64
-0.05
92.8
4288
71.59
0
0.00
0.0
83.28
13T02W
10:23
Low TW
Off
83
277.91
206.70
14.59
90.25
56.83
4297
21.41
7.07
-94.14
0.00
92.0
4297
71.21
0
0.00
0.0
83.05
13T03N
10:36
Low TW
Off
83
277.91
206.63
14.59
90.13
55.75
3635
19.28
10.59
-85.87
0.00
70.1
3635
71.28
0
0.00
0.0
88.34
13T04N
10:43
Low TW
Off
83
277.90
206.65
14.59
90.36
54.86
3385
17.91
11.43
-82.34
0.00
64.9
3385
71.25
0
0.00
0.0
88.14
13T05N
11:01
Low TW
Off
83
277.96
206.67
14.59
90.77
55.54
3205
16.75
11.84
-81.19
0.00
62.3
3205
71.29
0
0.00
0.0
87.04
13T06N
11:07
Low TW
Off
83
277.97
206.69
14.59
91.24
54.39
3064
15.81
12.19
-80.25
0.00
60.1
3064
71.28
0
0.00
0.0
85.95
13T07N
11:25
Low TW
Off
83
277.93
206.71
14.59
91.71
53.74
2934
14.94
12.54
-78.82
0.00
57.9
2934
71.22
0
0.00
0.0
84.91
13T08N
11:35
Low TW
Off
83
277.91
206.69
14.59
91.83
53.56
2597
12.82
13.43
-75.76
0.00
52.4
2597
71.22
0
0.00
0.0
82.25
13T09N
11:52
Low TW
Off
83
277.88
206.67
14.59
92.02
51.96
2463
11.98
13.78
-73.89
0.00
50.3
2463
71.21
0
0.00
0.0
81.08
13T10N
11:59
Low TW
Off
83
277.85
206.71
14.59
92.27
51.75
2305
10.97
14.15
-72.27
0.00
47.9
2305
71.14
0
0.00
0.0
79.44
13T11N
12:18
Low TW
Off
83
277.84
206.88
14.59
92.70
51.24
2136
9.86
14.60
-71.22
0.00
45.1
2136
70.96
4
0.69
0.0
77.25
13T12N
12:56
Mid TW
Off
83
277.87
208.09
14.59
93.59
51.52
2120
9.64
14.59
-71.07
0.00
45.2
2120
69.78
4
0.74
0.0
77.34
13T13N
13:16
Mid TW
Off
83
277.83
208.09
14.59
94.00
51.76
2610
12.68
13.31
-74.16
0.00
53.1
2610
69.74
4
0.80
0.0
82.70
13T14N
13:23
Mid TW
Off
83
277.82
208.13
14.59
93.91
52.23
2922
14.60
12.46
-76.20
0.00
58.5
2922
69.69
4
0.78
0.0
85.15
13T15N
13:39
Mid TW
Off
83
277.77
208.12
14.59
94.21
51.22
3262
16.78
11.57
-78.11
0.00
64.0
3262
69.66
4
0.78
0.0
87.67
13T16N
13:45
Mid TW
Off
83
277.77
208.10
14.59
94.32
50.66
3600
18.64
10.77
-80.83
0.00
69.0
3600
69.67
4
0.78
0.0
88.25
13T17N
14:03
Mid TW
Off
83
277.75
208.17
14.59
94.65
50.28
4398
20.99
5.87
-87.58
0.00
99.4
4398
69.58
4
0.85
0.0
81.42
13T18N
14:25
High TW
Off
83
277.74
208.87
14.59
94.83
49.96
4387
20.68
5.86
-82.55
0.00
99.5
4387
68.87
4
0.80
0.0
81.28
13T19N
14:48
High TW
Off
83
277.73
208.94
14.58
94.86
49.21
3845
19.32
9.27
-81.04
0.00
78.3
3845
68.79
3
0.67
0.0
86.70
13T20N
14:55
High TW
Off
83
277.72
208.94
14.58
94.84
50.90
3312
16.89
11.35
-77.55
0.00
65.4
3312
68.79
3
0.65
0.0
88.03
13T21N
15:12
High TW
Off
83
277.68
208.95
14.58
94.62
53.85
3009
14.98
12.11
-75.22
0.00
60.7
3009
68.73
3
0.53
0.0
86.01
13T22N
15:19
High TW
Off
83
277.66
208.92
14.58
94.62
54.35
2676
12.92
13.07
-73.13
0.00
54.7
2676
68.74
3
0.51
0.0
83.37
13T23N
15:36
High TW
Off
83
277.61
209.00
14.58
94.93
52.36
2184
9.90
14.35
-69.63
0.00
46.7
2184
68.62
3
0.65
0.0
78.41
13TOlA
10:04
Low TW
On
83
277.93
206.46
14.59
91.08
59.14
4181
21.23
5.85
-96.34
3.24
99.6
4252
71.47
121
23.67
0.6
82.93
13TO2Aa
10:26
Low TW
On
83
277.91
206.72
14.59
90.23
56.70
4170
21.10
7.09
-96.01
3.97
91.9
4168
71.19
133
26.17
0.6
84.42
13TO3A
10:31
Low TW
On
83
277.91
206.65
14.59
90.12
55.98
3602
19.12
10.59
-86.40
4.34
70.1
3602
71.25
139
27.35
0.8
88.42
13TO4A
10:48
Low TW
On
83
277.92
206.63
14.59
90.55
54.89
3387
17.93
11.42
-82.59
4.64
64.9
3388
71.29
144
28.28
0.8
88.10
13TO5A
10:56
Low TW
On
83
277.95
206.64
14.59
90.64
55.29
3202
16.74
11.84
-81.29
2.75
62.3
3203
71.31
111
21.79
0.7
87.00
13TO6A
11:13
Low TW
On
83
277.97
206.70
14.59
91.37
54.11
3066
15.82
12.19
-80.36
1.74
60.1
3067
71.27
88
17.34
0.6
85.91
13TO7A
11:20
Low TW
On
83
277.95
206.71
14.59
91.69
53.78
2927
14.90
12.54
-79.27
1.22
57.9
2925
71.24
74
14.52
0.5
84.90
13TO8A
11:40
Low TW
On
83
277.89
206.68
14.59
91.98
52.73
2597
12.81
13.42
-75.44
1.27
52.5
2602
71.21
76
14.84
0.6
82.09
13TO9A
11:47
Low TW
On
83
277.88
206.66
14.59
92.06
52.37
2462
11.97
13.78
-73.89
0.94
50.3
2462
71.22
65
12.75
0.5
81.07
13T10A
12:05
Low TW
On
83
277.85
206.77
14.59
92.34
51.80
2308
10.99
14.14
-72.69
0.31
48.0
2312
71.08
37
7.28
0.3
79.38
13T11A
12:12
Low TW
On
83
277.84
206.82
14.59
92.52
51.46
2134
9.85
14.60
-71.37
0.28
45.1
2135
71.02
35
6.92
0.3
77.15
13T12A
13:02
Mid TW
On
83
277.88
208.14
14.59
93.63
52.31
2112
9.58
14.59
-71.76
0.01
45.2
2112
69.74
5
0.99
0.0
77.20
13T13A
13:10
Mid TW
On
83
277.87
208.12
14.59
93.99
51.63
2601
12.63
13.34
-74.67
0.28
53.0
2589
69.75
35
6.95
0.3
83.00
13T14A
13:29
Mid TW
On
83
277.80
208.12
14.59
93.99
52.10
2920
14.59
12.45
-76.20
0.22
58.5
2923
69.68
31
6.18
0.2
85.07
13T15A
13:34
Mid TW
On
83
277.79
208.12
14.59
94.08
51.85
3266
16.81
11.55
-78.29
1.52
64.1
3272
69.67
83
16.26
0.5
87.53
13T16A
13:51
Mid TW
On
83
277.75
208.08
14.59
94.51
50.80
3575
18.53
10.77
-80.93
3.63
69.0
3575
69.68
128
25.11
0.7
88.32
13T17A
13:57
Mid TW
On
83
277.74
208.12
14.59
94.58
50.52
4234
20.66
5.86
-87.16
2.13
99.5
4234
69.62
98
19.25
0.5
83.19
13T18A
14:32
High TW
On
83
277.74
208.91
14.58
94.87
50.07
4266
20.43
5.87
-82.75
1.56
99.4
4266
68.83
84
16.50
0.4
82.60
13T19A
14:43
High TW
On
83
277.74
208.94
14.58
94.89
49.49
3838
19.30
9.19
-81.60
1.28
78.8
3856
68.80
76
14.92
0.4
86.36
13T20A
15:00
High TW
On
83
277.71
208.93
14.58
94.74
52.42
3314
16.90
11.35
-77.03
1.03
65.4
3314
68.78
68
13.36
0.4
88.03
13T21A
15:06
High TW
On
83
277.70
208.94
14.58
94.71
53.86
3011
15.00
12.11
-75.30
0.00
60.6
3010
68.76
3
0.64
0.0
86.04
13T22A
15:24
High TW
On
83
277.65
208.90
14.58
94.63
55.29
2681
12.95
13.06
-73.03
0.08
54.7
2685
68.75
18
3.62
0.1
83.27
13T23A
15:31
High TW
On
83
277.62
208.98
14.58
95.00
54.95
2202
10.02
14.30
-70.02
0.00
47.0
2222
68.64
3
0.68
0.0
77.96
21

Table 2.6. Unit 2 Turbine Aeration Tests
Common Data I Unit 2 Data I Calculations
22
Head-
Air:
Test Con -
Air
Water
Air
Air
Rel.
U2
U2 Gate
cover
U2 Air
Flow for
Gross
Air Val
Air
Water
Unit Effic
Run
Time
dition
Valve
Temp
HW
TW
Press
Temp.
Humid.
Flow
U2 MW
Stroke
Press
Flow
Gate Pos
Calcs
Head
ocity
Flow
Ratio
iency
EST
F
ft
ft
psia
F
%
cfs
MW
in
in H2O
in H2O
%
cfs
ft
ft/s
cfs
24TOIN
10:10
Low TW
Off
83
277.91
205.00
14.63
84.23
63.41
3448
18.26
13.67
-33.58
0.06
83.9
3448
72.91
0
0.00
0.0
86.22
24TO2N
10:36
Low TW
Off
83
277.91
206.49
14.63
84.51
61.04
3559
18.12
13.47
-29.70
0.06
85.2
3559
71.42
0
0.00
0.0
84.64
24TO3N
10:43
Low TW
Off
83
277.90
206.58
14.63
84.61
61.30
3243
17.14
15.16
-39.96
0.06
74.7
3243
71.32
0
0.00
0.0
87.96
24TO4N
11:03
Low TW
Off
83
277.88
206.74
14.62
84.89
60.03
3004
16.14
16.37
-47.71
0.06
67.2
3004
71.14
0
0.00
0.0
89.66
24TO5N
11:10
Low TW
Off
83
277.87
206.75
14.62
84.94
59.60
2775
14.99
17.48
-56.10
0.06
60.3
2775
71.13
0
0.00
0.0
90.17
24TO6N
11:25
Low TW
Off
83
277.84
206.76
14.62
85.00
57.62
2617
14.07
18.21
-61.51
0.06
55.8
2617
71.08
0
0.00
0.0
89.78
24TO7N
11:33
Low TW
Off
83
277.82
206.80
14.62
85.03
57.84
2418
12.83
18.92
-60.26
0.06
51.4
2418
71.03
0
0.00
0.0
88.68
24TO8N
11:48
Low TW
Off
83
277.81
206.81
14.62
85.23
57.09
2201
11.46
19.43
-57.98
0.06
48.2
2201
71.00
1
0.20
0.0
87.07
24TO9N
11:54
Low TW
Off
83
277.82
206.83
14.62
85.31
56.93
2083
10.72
19.78
-56.13
0.06
46.0
2083
70.99
0
0.00
0.0
86.09
24TION
12:09
Low TW
Off
83
277.87
206.92
14.62
85.53
56.81
1941
9.84
20.20
-53.35
0.06
43.4
1941
70.95
0
0.00
0.0
84.79
24T11N
12:22
Low TW
Off
83
277.87
206.92
14.61
85.69
56.68
1772
8.78
20.70
-49.82
0.06
40.3
1772
70.95
0
0.00
0.0
82.94
24T12N
13:08
Mid TW
Off
83
277.79
207.91
14.61
86.17
55.16
1756
8.58
20.71
-50.61
0.06
40.3
1756
69.88
0
0.00
0.0
82.99
24T13N
13:18
Mid TW
Off
83
277.77
207.97
14.60
86.16
54.43
2034
10.27
19.86
-55.27
0.06
45.6
2034
69.80
0
0.00
0.0
85.90
24T14N
13:35
Mid TW
Off
83
277.75
207.93
14.60
86.39
52.86
2418
12.63
18.80
-55.74
0.06
52.1
2418
69.82
0
0.00
0.0
88.81
24T15N
13:42
Mid TW
Off
83
277.75
207.85
14.60
86.45
52.07
2681
14.21
17.81
-51.61
0.06
58.2
2681
69.90
0
0.00
0.0
90.03
24T16N
13:58
Mid TW
Off
83
277.77
207.84
14.60
86.61
52.81
3097
16.23
15.76
-35.75
0.06
71.0
3097
69.93
0
0.00
0.0
88.97
24T17N
14:08
Mid TW
Off
83
277.77
207.80
14.60
86.73
52.95
3755
18.12
11.19
-15.99
0.06
99.4
3755
69.97
0
0.00
0.0
81.87
24T18N
14:50
HIgh TW
Off
83
277.67
208.80
14.59
91.49
46.19
3700
17.64
11.13
-9.47
0.06
99.7
3700
68.86
1
0.13
0.0
82.20
24T19N
15:00
HIgh TW
Off
83
277.65
208.86
14.59
92.25
44.96
3472
17.09
13.54
-17.14
0.06
84.8
3472
68.79
0
0.00
0.0
84.96
24T20N
15:17
High TW
Off
83
277.63
208.89
14.59
92.90
44.62
2895
15.08
16.68
-37.40
0.06
65.3
2895
68.74
0
0.07
0.0
89.97
24T21N
15:23
High TW
Off
83
277.62
208.91
14.59
93.08
44.17
2517
13.04
18.51
-49.97
0.06
53.9
2517
68.70
0
0.00
0.0
89.52
24T22N
15:38
High TW
Off
83
277.61
209.02
14.58
93.71
44.35
2156
10.85
19.41
-51.58
0.06
48.3
2156
68.60
0
0.00
0.0
87.11
2 4T23
15:44
HI hTW
On
83
277.61
209.05
14.58
93.85
43.37
1831
8.90
20.42
-54.61
0.06
42.1
1831
68.56
0
0.00
0.0
84.13
24TOIA
10:15
Low TW
On
83
277.91
205.69
14.63
84.30
63.10
3528
18.28
13.22
-32.54
0.89
86.8
3586
72.22
60
11.86
0.3
83.82
24TO2A
10:31
Low TW
On
83
277.91
206.43
14.63
84.48
61.00
3549
18.11
13.29
-29.96
0.58
86.3
3572
71.48
48
9.37
0.3
84.23
24TO3A
10:48
Low TW
On
83
277.90
206.67
14.63
84.71
61.62
3210
16.99
15.17
-40.52
0.18
74.6
3208
71.23
23
4.45
0.1
88.29
24TO4A
10:57
Low TW
On
83
277.91
206.72
14.63
84.85
60.72
2987
16.07
16.36
-48.60
0.31
67.2
2989
71.19
33
6.48
0.2
89.67
24TO5A
11:12
Low TW
On
83
277.88
206.84
14.62
84.97
58.94
2772
14.96
17.46
-55.45
0.62
60.4
2777
71.04
50
9.75
0.4
90.01
2 4T06
11:20
Low TW
On
83
277.86
206.76
14.62
85.01
56.92
2608
14.02
18.22
-61.34
1.14
55.7
2605
71.10
69
13.58
0.5
89.82
24TO7A
11:37
Low TW
On
83
277.82
206.79
14.62
85.07
57.95
2423
12.86
18.92
-59.53
1.26
51.3
2423
71.03
73
14.30
0.6
88.73
24TO8A
11:43
Low TW
On
83
277.81
206.80
14.62
85.19
57.26
2202
11.47
19.42
-58.13
0.34
48.2
2203
71.00
35
6.82
0.3
87.08
24T09A
1158
Low TW
On
83
277.85
206.86
14.62
85.39
56.98
2076
10.68
19.78
-56.37
0.31
46.0
2075
70.99
33
6.45
0.3
86.11
24TIOA
1205
Low TW
On
83
277.87
206.89
14.61
85.49
56.92
1941
9.84
20.21
-53.42
0.30
43.4
1940
70.98
32
6.31
0.3
84.82
24T11A
12:27
Low Tw
On
83
277.87
206.92
14.61
85.73
57.07
1773
8.79
20.70
-49.94
0.08
40.3
1774
70.95
10
1.91
0.1
82.91
24T1 2A
1304
Mid Tw
On
83
277.81
207.89
14.61
86.12
54.69
1759
8.60
20.71
-50.69
0.06
40.3
1759
69.92
0
0.00
0.0
83.00
24T13A
13:23
Mid TW
On
83
277.75
207.99
14.60
86.21
54.36
2032
10.25
19.86
-55.31
0.06
45.5
2031
69.76
3
0.60
0.0
85.91
24T14A
13:30
Mid TW
On
83
277.76
207.97
14.60
86.31
54.15
2418
12.62
18.81
-55.32
0.12
52.1
2417
69.80
16
3.14
0.1
88.84
2 4T15
1347
Mid Tw
On
83
277.77
207.82
14.60
86.50
52.20
2679
14.21
17.81
-51.87
0.12
58.3
2680
69.95
16
3.18
0.1
89.96
24T1 6A
1353
Mid TW
On
83
277.76
207.85
14.60
86.57
52.91
3093
16.21
15.76
-36.00
0.07
71.0
3091
69.92
8
1.52
0.0
89.03
24T1 7A
1412
Mid TW
On
83
277.76
207.80
14.60
86.80
53.36
3730
18.07
11.15
-15.79
0.28
99.6
3733
69.97
31
6.15
0.2
82.12
24T1 8A
1445
HIgh TW
On
83
277.67
208.76
14.59
90.95
47.76
3693
17.64
11.17
-10.21
0.08
99.5
3690
68.91
8
1.64
0.0
82.36
24T1 9A
15:05
Hi gh TW
On
83
277.64
208.86
14.59
92.51
45.03
3479
17.11
13.55
-17.43
0.06
84.7
3479
68.78
0
0.04
0.0
84.89
24T2 OA
1512
HIgh TW
On
83
277.63
208.89
14.59
92.78
44.57
2898
15.10
16.66
-37.72
0.06
65.4
2902
68.74
0
0.00
0.0
89.86
24T21A
15:27
High Tw
On
83
277.62
208.93
14.58
93.20
44.29
2516
13.03
18.51
-49.63
0.06
53.9
2516
68.69
0
0.00
0.0
89.49
24T22A
15:34
HIgh TW
On
83
277.63
208.99
14.58
93.55
44.80
2157
10.86
19.41
-51.43
0.06
48.3
2157
68.64
0
0.00
0.0
87.10
24T23A
15:49
HI hTW
On
83
277.61
209.08
14.58
94.03
43.06
1822
8.84
20.43
-52.43
0.06
42.0
1821
68.53
1
0.21
0.0
84.11
22

Table 2.7. Unit 3 Turbine Aeration Tests
Common Data I Unit 3 Data I Calculations
23
U3
Head-
Flow
Air:
Test Con-
Air
Water
Air
Air
Rel.
U3
Gate
cover
U3 Air
Gate
for
Gross
Air Vel-
Air
Water
Unit Effic
Run
Time
dition
Valve
Temp
HW
TW
Press.
Temp.
Humid.
Flow
U3 MW
Stroke
Press
Flow
Pos
Calcs
Head
ocity
Flow
Ratio
iency
EST
F
ft
ft
psia
F
%
cfs
MW
in
in H2O in H2O
%
cfs
ft
ft/s
cfs
13T0lN
9:59
Low TW
Off
83
277.94
206.35
14.59
91.01
59.28
2050
9.40
8.97
-66.43
0.01
43.6
2050
71.59
0
0.00
0.0
76.05
13T02W
10:23
Low TW
Off
83
277.91
206.70
14.59
90.25
56.83
2214
10.44
9.38
-65.47
0.01
46.1
2214
71.21
0
0.00
0.0
78.59
13T03N
10:36
Low TW
Off
83
277.91
206.63
14.59
90.13
55.75
2392
11.56
9.84
25.18
0.01
48.9
2392
71.28
0
0.00
0.0
80.48
13T04N
10:43
Low TW
Off
83
277.90
206.65
14.59
90.36
54.86
2555
12.55
10.23
25.29
0.01
51.3
2555
71.25
0
0.00
0.0
81.80
13T05N
11:01
Low TW
Off
83
277.96
206.67
14.59
90.77
55.54
2896
14.65
11.07
25.17
0.01
56.5
2896
71.29
0
0.00
0.0
84.26
13T06N
11:07
Low TW
Off
83
277.97
206.69
14.59
91.24
54.39
3058
15.73
11.53
24.74
0.01
59.3
3058
71.28
0
0.00
0.0
85.66
13T07N
11:25
Low TW
Off
83
277.93
206.71
14.59
91.71
53.74
3221
16.86
11.97
24.13
0.01
62.0
3221
71.22
0
0.00
0.0
87.28
13TO8N
11:35
Low TW
Off
83
277.91
206.69
14.59
91.83
53.56
3361
17.85
12.33
23.92
0.01
64.3
3361
71.22
0
0.00
0.0
88.51
13T09N
11:52
Low TW
Off
83
277.88
206.67
14.59
92.02
51.96
3503
18.73
12.67
24.16
0.01
66.4
3503
71.21
0
0.00
0.0
89.13
13T10N
11:59
Low TW
Off
83
277.85
206.71
14.59
92.27
51.75
3964
20.55
15.19
14.44
0.01
81.9
3964
71.14
0
0.00
0.0
86.52
13T11N
12:18
Low TW
Off
83
277.84
206.88
14.59
92.70
51.24
4411
21.47
17.95
12.25
0.01
98.9
4411
70.96
0
0.00
0.0
81.42
13T12N
12:56
Mid TW
Off
83
277.87
208.09
14.59
93.59
51.52
4404
20.98
17.96
11.91
0.01
99.0
4404
69.78
0
0.00
0.0
81.06
13T13N
13:16
Mid TW
Off
83
277.83
208.09
14.59
94.00
51.76
3647
19.01
13.63
18.59
0.01
72.3
3647
69.74
0
0.00
0.0
88.74
13T14N
13:23
Mid TW
Off
83
277.82
208.13
14.59
93.91
52.23
3274
16.93
12.26
20.82
0.01
63.9
3274
69.69
0
0.00
0.0
88.07
13T15N
13:39
Mid TW
Off
83
277.77
208.12
14.59
94.21
51.22
2996
15.00
11.50
21.39
0.01
59.1
2996
69.66
0
0.00
0.0
85.35
13T16N
13:45
Mid TW
Off
83
277.77
208.10
14.59
94.32
50.66
2662
12.92
10.56
23.21
0.01
53.4
2662
69.67
0
0.00
0.0
82.72
13T17N
14:03
Mid TW
Off
83
277.75
208.17
14.59
94.65
50.28
2164
9.92
9.36
22.55
0.01
46.0
2164
69.58
0
0.00
0.0
78.21
13T18N
14:25
High TW
Off
83
277.74
208.87
14.59
94.83
49.96
2152
9.75
9.36
22.08
0.01
46.0
2152
68.87
0
0.00
0.0
78.14
13T19N
14:48
High TW
Off
83
277.73
208.94
14.58
94.86
49.21
2622
12.54
10.52
21.92
0.01
53.1
2622
68.79
0
0.00
0.0
82.54
13T20N
14:55
High TW
Off
83
277.72
208.94
14.58
94.84
50.90
2958
14.60
11.45
21.65
0.01
58.9
2958
68.79
0
0.00
0.0
85.19
13T21N
15:12
High TW
Off
83
277.68
208.95
14.58
94.62
53.85
3294
16.86
12.41
18.51
0.01
64.8
3294
68.73
0
0.00
0.0
88.39
13T22N
15:19
High TW
Off
83
277.66
208.92
14.58
94.62
54.35
3592
18.48
13.15
18.26
0.01
69.3
3592
68.74
0
0.00
0.0
88.86
13T23
15:36
High TW
Off
83
277.61
209.00
14.58
94.93
52.36
4393
20.53
17.95
10.93
0.01
98.9
4393
68.62
0
0.00
0.0
80.86
13T0lA
10:04
Low TW
On
83
277.93
206.46
14.59
91.08
59.14
2061
9.46
9.01
-67.42
0.01
43.8
2078
71.47
0
0.00
0.0
75.66
13T02Aa
10:26
Low TW
On
83
277.91
206.72
14.59
90.23
56.70
2215
10.44
9.41
39.76
0.01
46.3
2228
71.19
0
0.00
0.0
78.14
13T03A
10:31
Low TW
On
83
277.91
206.65
14.59
90.12
55.98
2377
11.46
9.80
25.14
0.01
48.7
2360
71.25
0
0.00
0.0
80.92
13T04A
10:48
Low TW
On
83
277.92
206.63
14.59
90.55
54.89
2557
12.56
10.22
25.38
0.01
51.3
2557
71.29
0
0.00
0.0
81.83
13T05A
10:56
Low TW
On
83
277.95
206.64
14.59
90.64
55.29
2895
14.65
11.07
25.20
0.01
56.5
2896
71.31
0
0.00
0.0
84.23
13T06A
11:13
Low TW
On
83
277.97
206.70
14.59
91.37
54.11
3070
15.81
11.56
24.75
0.01
59.5
3080
71.27
0
0.00
0.0
85.49
13T07A
11:20
Low TW
On
83
277.95
206.71
14.59
91.69
53.78
3231
16.94
12.00
24.13
0.01
62.2
3240
71.24
0
0.00
0.0
87.12
13TO8A
11:40
Low TW
On
83
277.89
206.68
14.59
91.98
52.73
3360
17.83
12.33
24.00
3.17
64.2
3359
71.21
119
23.39
0.7
88.51
13T09A
11:47
Low TW
On
83
277.88
206.66
14.59
92.06
52.37
3487
18.64
12.66
23.99
4.05
66.3
3483
71.22
135
26.44
0.8
89.22
13T10A
12:05
Low TW
On
83
277.85
206.77
14.59
92.34
51.80
3968
20.54
15.43
12.94
3.26
83.4
4013
71.08
121
23.72
0.6
85.50
13T11A
12:12
Low TW
On
83
277.84
206.82
14.59
92.52
51.46
4288
21.26
17.79
9.72
3.03
97.9
4276
71.02
116
22.87
0.5
83.13
13T12A
13:02
Mid TW
On
83
277.88
208.14
14.59
93.63
52.31
4305
20.79
17.95
12.32
2.00
98.9
4304
69.74
95
18.62
0.4
82.24
13T13A
13:10
Mid TW
On
83
277.87
208.12
14.59
93.99
51.63
3709
19.25
13.64
21.68
3.06
72.4
3711
69.75
117
23.01
0.6
88.31
13T14A
13:29
Mid TW
On
83
277.80
208.12
14.59
93.99
52.10
3270
16.90
12.26
20.79
0.01
63.8
3269
69.68
0
0.00
0.0
88.07
13T15A
13:34
Mid TW
On
83
277.79
208.12
14.59
94.08
51.85
2993
14.99
11.49
21.44
0.01
59.1
2991
69.67
0
0.00
0.0
85.40
13T16A
13:51
Mid TW
On
83
277.75
208.08
14.59
94.51
50.80
2658
12.90
10.55
23.23
0.01
53.3
2656
69.68
0
0.00
0.0
82.74
13T17A
13:57
Mid TW
On
83
277.74
208.12
14.59
94.58
50.52
2163
9.92
9.36
22.76
0.01
45.9
2159
69.62
0
0.00
0.0
78.34
13T18A
14:32
High TW
On
83
277.74
208.91
14.58
94.87
50.07
2152
9.75
9.36
21.99
0.01
46.0
2151
68.83
0
0.00
0.0
78.18
13T19A
14:43
High TW
On
83
277.74
208.94
14.58
94.89
49.49
2617
12.51
10.49
21.92
0.01
52.9
2603
68.80
0
0.00
0.0
82.94
13T20A
15:00
High TW
On
83
277.71
208.93
14.58
94.74
52.42
2965
14.64
11.47
21.57
0.01
58.9
2969
68.78
0
0.00
0.0
85.12
13T21A
15:06
High TW
On
83
277.70
208.94
14.58
94.71
53.86
3253
16.59
12.32
18.58
0.01
64.2
3226
68.76
0
0.00
0.0
88.79
13T22A
15:24
High TW
On
83
277.65
208.90
14.58
94.63
55.29
3595
18.49
13.15
18.32
2.47
69.3
3594
68.75
105
20.70
0.6
88.88
13T23A
15:31
High TW
On
83
277.62
208.98
14.58
95.00
54.95
4296
20.37
17.94
10.05
1.48
98.9
4295
68.64
82
16.00
0.4
82.04
23

Table 2.8. Unit 4 Turbine Aeration Tests
24
U4 Head-
Flow
Air
Test Con-
Air
Water
Air
Air
Rel.
U4
Gate cover
U4 Air
for
Gross
Veloci
Air
Air:Wat
Unit Effi-
Run
Time
dition
Valve
Temp
HW
TW
Press.
Temp.
Humid.
Flow
U4 MW
Stroke Press.
Flow
Gate A
Calcs
Head
ty
Flow
er
ciency
EST
F
ft
ft
psia
F
%
cfs
MW
in in H2O
in H2O
%
cfs
ft
ftts
cfs
24TOIN
10:10
Low TW
Off
83
277.91
205.00
14.63
84.23
63.41
2314
8.68
28.20 -95.79
13.53
34.6
2314
72.91
241
84.28
3.6
61.09
24TO2N
10:36
Low TW
Off
83
277.91
206.49
14.63
84.51
61.04
2627
10.72
27.31 -68.06
8.55
39.9
2627
71.42
193
67.37
2.6
67.81
24TO3N
10:43
Low TW
Off
83
277.90
206.58
14.63
84.61
61.30
2868
12.44
26.37 -19.77
0.33
45.6
2868
71.32
36
12.57
0.4
72.19
24TO4N
11:03
Low TW
Off
83
277.88
206.74
14.62
84.89
60.03
3152
14.56
25.44 76.46
0.04
51.1
3152
71.14
2
0.62
0.0
77.11
24TO5N
11:10
Low TW
Off
83
277.87
206.75
14.62
84.94
59.60
3390
16.47
24.86 152.86
0.04
54.6
3390
71.13
2
0.58
0.0
81.08
24TO6N
11:25
Low TW
Off
83
277.84
206.76
14.62
85.00
57.62
3653
18.59
23.88 231.81
0.03
60.4
3653
71.08
0
0.00
0.0
85.01
24TO7N
11:33
Low TW
Off
83
277.82
206.80
14.62
85.03
57.84
3911
20.57
23.10 280.46
0.04
65.0
3911
71.03
0
0.00
0.0
87.90
24TO8N
11:48
Low TW
Off
83
277.81
206.81
14.62
85.23
57.09
4209
22.56
22.12 335.25
0.04
70.9
4209
71.00
0
0.00
0.0
89.64
24TO9N
11:54
Low TW
Off
83
277.82
206.83
14.62
85.31
56.93
4559
24.48
20.63 409.21
0.04
79.8
4559
70.99
0
0.00
0.0
89.81
24TION
12:09
Low TW
Off
83
277.87
206.92
14.62
85.53
56.81
4909
26.01
18.03 479.28
0.04
95.3
4909
70.95
0
0.00
0.0
88.67
24T11N
12:22
Low TW
Off
83
277.87
206.92
14.61
85.69
56.68
4927
26.08
17.97 481.38
0.04
95.7
4927
70.95
0
0.00
0.0
88.58
24T12N
13:08
Mid TW
Off
83
277.79
207.91
14.61
86.17
55.16
4789
25.14
18.45 477.68
0.04
92.8
4789
69.88
0
0.00
0.0
89.19
24T13N
13:18
Mid TW
Off
83
277.77
207.97
14.60
86.16
54.43
4740
24.89
18.93 467.10
0.04
89.9
4740
69.80
0
0.00
0.0
89.33
24T14N
13:35
Mid TW
Off
83
277.75
207.93
14.60
86.39
52.86
3995
20.79
22.89 305.04
0.03
66.3
3995
69.82
0
0.00
0.0
88.47
24T15N
13:42
Mid TW
Off
83
277.75
207.85
14.60
86.45
52.07
3452
16.70
24.43 186.42
0.03
57.1
3452
69.90
0
0.00
0.0
82.15
24T16N
13:58
Mid TW
Off
83
277.77
207.84
14.60
86.61
52.81
2914
12.58
25.98 38.35
0.03
47.9
2914
69.93
0
0.00
0.0
73.29
24T17N
14:08
Mid TW
Off
83
277.77
207.80
14.60
86.73
52.95
2323
8.48
28.08 -85.04
11.74
35.3
2323
69.97
226
78.93
3.4
61.93
24T18N
14:50
High TW
Off
83
277.67
208.80
14.59
91.49
46.19
2364
8.65
27.83 -80.19
10.81
36.8
2364
68.86
218
76.17
3.2
63.07
24T19N
15:00
High TW
Off
83
277.65
208.86
14.59
92.25
44.96
2621
10.36
27.07 -53.77
5.86
41.3
2621
68.79
161
56.37
2.2
68.19
24T20N
15:17
High TW
Off
83
277.63
208.89
14.59
92.90
44.62
2953
12.65
25.81 61.59
0.03
48.9
2953
68.74
0
0.00
0.0
73.97
24T21N
15:23
High TW
Off
83
277.62
208.91
14.59
93.08
44.17
3592
17.47
23.94 237.60
0.03
60.1
3592
68.70
0
0.00
0.0
84.02
24T22N
15:38
High TW
Off
83
277.61
209.02
14.58
93.71
44.35
4362
22.56
21.54 388.88
0.03
74.3
4362
68.60
0
0.00
0.0
89.52
24T23N
15:44
HI hTW
Off
83
277.61
209.05
14.58
93.85
43.37
4764
24.45
18.71 483.68
0.03
91.2
4764
68.56
0
0.00
0.0
88.85
24TOIA
10:15
Low TW
On
83
277.91
205.69
14.63
84.30
63.10
2277
8.36
28.23 -93.05
13.05
34.5
2277
72.22
237
82.83
3.6
60.38
24TO2A
10:31
Low TW
On
83
277.91
206.43
14.63
84.48
61.00
2610
10.60
27.35 -71.40
9.11
39.7
2610
71.48
199
69.51
2.7
67.48
24TO3A
10:48
Low TW
On
83
277.90
206.67
14.63
84.71
61.62
2866
12.41
26.14 15.43
0.04
46.9
2866
71.23
0
0.00
0.0
72.17
24TO4A
10:57
Low TW
On
83
277.91
206.72
14.63
84.85
60.72
3143
14.50
25.47 79.77
0.04
50.9
3143
71.19
1
0.23
0.0
76.95
24TO5A
11:12
Low TW
On
83
277.88
206.84
14.62
84.97
58.94
3415
16.65
24.75 152.82
0.03
55.2
3415
71.04
0
0.00
0.0
81.48
24TO6A
11:20
Low TW
On
83
277.86
206.76
14.62
85.01
56.92
3636
18.46
23.90 228.34
0.03
60.3
3636
71.10
0
0.00
0.0
84.78
24TO7A
11:37
Low TW
On
83
277.82
206.79
14.62
85.07
57.95
3881
20.35
23.19 276.33
0.03
64.5
3881
71.03
0
0.00
0.0
87.63
24TO8A
11:43
Low TW
On
83
277.81
206.80
14.62
85.19
57.26
4265
22.90
22.04 346.14
0.03
71.4
4265
71.00
0
0.00
0.0
89.79
24TO9A
11:58
Low TW
On
83
277.85
206.86
14.62
85.39
56.98
4553
24.45
20.49 407.62
0.04
80.6
4553
70.99
0
0.00
0.0
89.82
24TIOA
12:05
Low TW
On
83
277.87
206.89
14.61
85.49
56.92
4913
26.04
18.18 479.72
0.04
94.4
4913
70.98
0
0.00
0.0
88.65
24T11A
12:27
Low TW
On
83
277.87
206.92
14.61
85.73
57.07
4897
25.97
18.17 476.82
0.04
94.5
4897
70.95
0
0.00
0.0
88.72
24T12A
13:04
Mid TW
On
83
277.81
207.89
14.61
86.12
54.69
4806
25.23
18.36 480.93
0.04
93.3
4806
69.92
0
0.00
0.0
89.14
24T13A
13:23
Mid TW
On
83
277.75
207.99
14.60
86.21
54.36
4755
24.94
18.79 471.45
0.04
90.7
4755
69.76
0
0.00
0.0
89.27
24T14A
13:30
Mid TW
On
83
277.76
207.97
14.60
86.31
54.15
3933
20.34
22.97 295.11
0.04
65.8
3933
69.80
0
0.00
0.0
87.99
24T15A
13:47
Mid TW
On
83
277.77
207.82
14.60
86.50
52.20
3432
16.55
24.55 178.20
0.03
56.4
3432
69.95
0
0.00
0.0
81.84
24T16A
13:53
Mid TW
On
83
277.76
207.85
14.60
86.57
52.91
2917
12.60
25.94 43.92
0.03
48.1
2917
69.92
0
0.00
0.0
73.35
24T17A
14:12
Mid TW
On
83
277.76
207.80
14.60
86.80
53.36
2336
8.57
28.00 -86.22
11.89
35.8
2336
69.97
228
79.41
3.4
62.24
24T18A
14:45
High TW
On
83
277.67
208.76
14.59
90.95
47.76
2333
8.45
27.99 -82.16
11.15
35.9
2333
68.91
221
77.30
3.3
62.39
24T19A
15:05
High TW
On
83
277.64
208.86
14.59
92.51
45.03
2639
10.47
27.04 -49.50
4.94
41.6
2639
68.78
148
51.81
2.0
68.51
24T20A
15:12
High TW
On
83
277.63
208.89
14.59
92.78
44.57
2928
12.47
25.85 60.70
0.03
48.6
2928
68.74
0
0.00
0.0
73.55
24T21A
15:27
High TW
On
83
277.62
208.93
14.58
93.20
44.29
3628
17.73
23.83 244.76
0.03
60.7
3628
68.69
0
0.00
0.0
84.49
24T22A
15:34
High TW
On
83
277.63
208.99
14.58
93.55
44.80
4353
22.53
21.61 386.49
0.03
73.9
4353
68.64
0
0.00
0.0
89.53
24T23A
15:49
HI hTW
On
83
277.61
209.08
14.58
94.03
43.06
4773
24.47
18.50 486.04
0.03
92.5
4773
68.53
0
0.00
0.0
88.81
24

Table 2.9. Unit 1 Tailrace DO Uptake Tests
Table 2.10. Unit 2 Tailrace DO Uptake Tests
Common Data
Mechanical Data
Mechanical Data
Water Quality Data
Water Quality Data
Calculations
Calculations
Air'
Air'
Air
Air
Air
Re 1.
U1
U1 Gate
U1 Air
Water
Conduc-
DO
TDG
DO
Gate
Gross
Air Vel-
Air
Water
Air
Air
Air
Re 1.
U1
U2 Gate
U2 Air
Temp
tivity
DO
Temp
tivity
Gate
Gross
Uptake
Air
Water
Run
Time
Valve
Run
Time
Valve
HW
TW
Press.
Temp.
Humid.
Flow
U1 MW
Stroke
Flow
Opening
Head
ocity
Opening
Head
ocity
Flow
Ratio
ft
EST
ft
F
ft
psia
F
%
cfs
MW
in
in H2O
C
28.24
usi
90.89
mg /l
1.38
mmHg
740
mg /l
%
ft
ft/s
cfs
1755 8.87 20.83 0.03
1T07N 9:47 Off
277.68 205.06 14.67 89.42 63.67
2111 9.85 14.77 0.00
- 44.1 72.61 3.4 0.7
0.0
1T08N
10:17
Off
277.64
92.28
205.18
14.66
89.96
62.48
0.03
2555
12.72
13.62
0.00
28.31
90.66
1.58
728
0.0
51.2
72.46
3.0
0.6
0.0
1T09N
10:33
Off
277.64
52.75
205.29
14.66
90.18
62.32
28.30
2870
14.78
12.77
0.00
28.35
90.17
1.64
720
-
56.5
72.35
2.9
0.6
0.0
1TION
10:58
Off
277.75
2618
205.45
14.66
90.25
62.33
89.00
3200
16.92
11.92
0.00
28.33
90.62
1.67
731
-
61.8
72.30
3.4
0.7
0.0
1T11N
11:10
Off
277.84
16.30
205.53
14.66
90.15
62.69
2.43
3490
18.80
11.24
0.00
28.33
90.63
1.67
723
-
66.0
72.31
3.5
0.7
0.0
1T12N
11:45
Off
1 277.82
13.58
205.93
14.66
90.61
62.28
754
1 4379
21.85
5.85
0.00
1 28.51
89.83
1.95
736
-
99.6
71.89
3.4
0.7
0.0
1T07A
9:56
On
277.66
1.28
205.04
14.67
89.63
63.57
0.83
2109
9.84
14.77
1.68
28.22
90.09
2.37
734
0.99
44.1
72.62
86.4
17.0
0.8
1T08A
10:05
On
277.66
28.15
205.12
14.67
89.82
63.36
43.6
2532
12.59
13.67
2.38
28.32
88.64
2.64
742
1.06
50.9
72.54
103.0
20.2
0.8
1T09A
10:38
On
277.64
88.17
205.32
14.66
90.00
62.65
72.93
2870
14.71
12.77
2.67
28.34
88.65
2.61
730
0.96
56.5
72.33
109.0
21.4
0.7
1TIOA
10:47
On
277.67
2.97
205.39
14.66
90.24
62.40
107.6
3159
16.64
12.02
3.94
28.33
89.84
2.70
741
1.04
61.2
72.28
132.4
26.0
0.8
1T11A
11:21
On
277.84
751
205.56
14.66
90.54
61.98
11.2
3479
18.73
11.24
6.84
28.34
85.92
2.70
729
1.03
66.0
72.28
174.0
34.2
1.0
1T12A
11:34
On
1 277.82
0.69
205.83
14.66
90.31
62.74
0.4
4155
21.36
5.85
3.77
28.51
88.37
2.86
742
0.91
99.5
71.99
129.6
25.4
0.6
Table 2.10. Unit 2 Tailrace DO Uptake Tests
25
Common Data
Mechanical Data
Water Quality Data
Calculations
Air'
Water
Conduc-
DO
Air
Air
Air
Re 1.
U1
U2 Gate
U2 Air
Temp
tivity
DO
TDG
Uptake
Gate
Gross
Air Vel-
Air
Water
Run
Time
Valve
HW
TW
Press.
Temp.
Humid.
Flow
U2 MW
Stroke
Flow
Opening
Head
ocity
Flow
Ratio
EST
ft
ft
psia
F
%
cfs
MW
in
in H2O
C
28.07
usi
89.24
mg /l
1.87
mm Hg
725
mg /l
%
ft
ft/s
cfs
2TO7N 13:42 Off
277.78 204.82 14.57 91.81 54.44
1755 8.87 20.83 0.03
39.5 72.96 0.0 0.0
0.0
2TO8N
14:03
Off
277.88
204.88
14.57
92.28
53.02
1983
10.33
20.16
0.03
28.10
89.25
1.95
749
43.7
73.00
0.0
0.0
0.0
2TO9N
14:09
Off
277.89
204.94
14.57
92.40
52.75
2283
12.27
19.32
0.03
28.30
89.00
2.31
742
48.9
72.95
0.0
0.0
0.0
2TION
14:41
Off
277.92
205.13
14.56
93.10
46.36
2618
14.40
18.30
0.03
28.28
89.00
2.29
748
-
55.2
72.79
0.0
0.0
0.0
2T11N
14:52
Off
277.92
205.27
14.56
93.34
45.67
2961
16.30
16.71
0.03
28.33
88.94
2.43
746
-
65.1
72.65
0.0
0.0
0.0
2T12N
15:17
Off
277.92
205.52
14.55
93.74
44.06
3549
18.40
13.58
0.03
28.39
88.88
2.53
754
84.5
72.40
0.0
0.0
0.0
2TO7A
13:47
On
277.81
204.80
14.57
91.97
54.09
1749
8.84
20.83
1.28
28.04
89.24
2.70
740
0.83
39.5
73.00
74.0
14.5
0.8
2TO8A
13:57
On
277.84
204.85
14.57
92.18
52.82
1958
10.17
20.17
1.67
28.15
89.07
2.91
750
0.96
43.6
72.99
85.3
16.7
0.9
2T09A
14:16
On
277.91
204.98
14.57
92.52
52.31
2283
12.26
19.32
2.22
28.20
88.17
3.03
740
0.72
48.9
72.93
98.6
19.4
0.8
2TIOA -1
14:29
On
277.90
205.06
14.57
92.73
51.14
2598
14.28
18.30
2.63
28.08
89.29
2.97
758
0.68
55.2
72.84
107.6
21.1
0.8
2T11A
15:04
On
277.91
205.34
14.55
93.44
45.98
2960
16.28
16.46
0.78
28.35
88.95
2.99
751
0.56
66.6
72.58
57.1
11.2
0.4
2T12A
15:11
On
277.91
205.43
14.55
93.57
45.44
3494
18.26
13.57
1.20
28.39
88.94
3.22
757
0.69
84.6
72.48
71.8
14.1
0.4
25

Table 2.11. Unit 3 Tailrace DO Uptake Tests
Table 2.12. Unit 4 Tailrace DO Uptake Tests
Common Data
Mechanical Data
Water Quality Data
Calculations
U3
Air'
Air
Air
Air
Re 1.
U1
U4 Gate
U4 Air
Water
Conduc-
DO
TDG
DO
Gate
Gross
Air Vel-
Air
Water
Air
Air
Air
Re 1.
U1
Gate
U3Air
Temp
tivity
DO
TDG
Uptake
Gate
Gross
Air Vel-
Air
Water
Run
Time
Valve
HW
TW
Press.
Temp.
Humid.
Flow
U3 MW
Stroke
Flow
Opening
Head
ocity
Flow
Ratio
EST
ft
ft
psia
F
%
cfs
MW
in
in H2O
C
28.14
usi
91.71
mg /l
1.29
mm Hg
760
mg /l
%
ft
ft/s
cfs
3TO1N 6:30 Off
277.80 204.95 14.64 86.68 69.27
2104 9.90 9.02 0.01
- 43.9 72.85 0.0 0.0
0.0
3TO2N
7:10
Off
277.81
205.21
14.65
89.29
64.73
2533
12.62
10.11
0.01
28.26
90.96
1.55
709
-
50.6
72.61
0.0
0.0
0.0
3TO3N
7:20
Off
277.83
205.29
14.65
89.72
64.06
2848
14.58
10.88
0.01
28.32
91.00
1.65
708
3.5
55.3
72.54
0.0
0.0
0.0
3TO4N
7:58
Off
277.75
205.50
14.66
89.03
64.82
3183
16.79
11.80
0.01
28.52
90.14
1.90
723
3.0
61.0
72.25
0.0
0.0
0.0
3TO5N
8:16
Off
277.72
205.59
14.66
89.70
63.41
3471
18.77
12.53
0.01
28.42
90.21
1.85
713
0.3
65.5
72.13
0.0
0.0
0.0
3TO6N
8:52
Off
277.71
206.00
14.67
88.39
65.59
4400
21.75
17.56
0.01
28.52
90.19
1.98
736
0.0
96.5
71.71
0.0
0.0
0.0
3TO1A
6:35
On
277.79
204.97
14.65
86.96
68.58
2102
9.89
9.03
0.01
28.16
91.54
1.32
736
0.03
43.9
72.83
0.0
0.0
0.0
3TO2A1
7:02
On
277.81
205.18
14.65
89.09
65.05
2530
12.61
10.11
0.01
28.25
91.13
1.52
717
-0.02
50.6
72.63
0.0
0.0
0.0
3TO3A
7:35
On
277.82
205.35
14.65
89.29
64.63
2850
14.58
10.90
1.96
28.45
90.25
3.01
723
1.36
55.5
72.47
93.1
18.3
0.6
3TO4A
7:45
On
277.79
205.45
14.66
88.32
66.24
3182
16.81
11.80
2.73
28.53
85.96
3.20
759
1.31
61.0
72.33
110.0
21.6
0.7
3TO5A
8:28
On
277.71
205.62
14.67
88.29
65.41
3466
18.73
12.53
4.74
28.63
88.27
3.43
736
1.59
65.5
72.09
144.7
28.4
0.8
3TO6A
8:42
On
277.70
205.90
14.67
87.64
66.68
4265
21.53
17.54
3.59
28.52
88.13
2.70
747
0.72
96.4
71.81
126.0
24.7
0.6
Table 2.12. Unit 4 Tailrace DO Uptake Tests
26
Common Data
Mechanical Data
Water Quality Data
Calculations
Air'
Air
Air
Air
Re 1.
U1
U4 Gate
U4 Air
Water
Conduc-
DO
TDG
DO
Gate
Gross
Air Vel-
Air
Water
Temp
tivity
Uptake
Run
Time
Valve
HW
TW
Press.
Temp.
Humid.
Flow
U4 MW
Stroke
Flow
Opening
Head
ocity
Flow
Ratio
EST
ft
ft
psia
F
%
cfs
MW
in
in H2O
C
usi
mg /l
mm Hg
mg /l
%
ft
ft/s
cfs
4TO1
11:08
Auto
277.80
204.94
14.58
87.54
59.48
2288
8.50
28.36
13.80
28.11
100.00
5.49
806
2.74
33.7
72.86
244.9
85.5
3.7
4TO2
11:15
Auto
277.79
205.03
14.58
87.85
60.01
2440
9.55
27.94
13.76
28.16
100.00
5.48
841
2.73
36.2
72.76
244.6
85.4
3.5
4TO3
11:42
Auto
277.77
205.20
14.58
88.89
59.53
2580
10.51
27.53
11.55
28.20
100.00
5.29
850
2.54
38.6
72.57
224.9
78.5
3.0
4TO4
12:02
Auto
277.79
205.44
14.58
89.35
56.46
2982
13.43
26.05
0.22
28.25
100.00
2.75
797
0.00
47.5
72.36
28.0
9.8
0.3
4TO5
12:22
Auto
277.78
205.68
14.58
89.93
57.68
3618
18.57
24.04
0.03
28.35
100.00
2.51
778
0.00
59.4
72.09
0.0
0.0
0.0
4TO6
12:35
Auto
277.77
206.01
14.58
90.29
55.49
4912
26.31
18.35
0.03
28.35
100.00
2.60
762
0.00
93.4
71.76
0.0
0.0
0.0
26

3.0 OXYGEN DIFFUSER TESTS
The fully operational Tillery reservoir oxygen diffuser system was tested during the week of August 8 -12,
2011, to verify DO enhancement capability over a wide range of hydro operations. Measurements of
water quality conditions in the reservoir and tailrace were acquired in addition to operational data for the
hydro turbines and oxygen diffuser system. The target DO compliance level of 5.0 mg /L was achieved
during these tests.
3.1 Description of the Oxygen Diffuser
The oxygenation technology deployed at the Tillery Development is a diffuser pipe system installed in the
reservoir to release oxygen in the forebay of the reservoir. Figure 3 -1 presents a conceptual drawing of
oxygen diffuser operation. Lengths of porous hose are installed near the bottom of the reservoir. Oxygen
is supplied to the diffusers from a nearby liquid oxygen storage facility located on the east bank of the
reservoir. After the liquid oxygen is vaporized into a gaseous state at the storage facility, it flows through
a supply hose to the diffuser hose and is uniformly released along the length of the porous hose. The
oxygen dissolves into the water that is drawn into the turbines while they operate and thereby provide DO
to the downstream tailrace.
Figure 3 -2 shows the layout of the Tillery oxygen diffusers. Four separate lines, each of which is 3,500
feet in length, were installed at approximately 54 feet (Lines 1 and 4) and 65 feet in depth (Lines 2 and 3).
This system provides a maximum oxygen flow rate of 150 tons per day. With an expected oxygen
transfer efficiency of 85 %, the system is capable of providing a flow rate of 127.5 tons per day that is
dissolved in the reservoir and can be subsequently drawn into the turbines for release in the tailrace.
Figure 3 -1. Schematic of an Oxygen Diffuser
27

Tillery 02 Testing Points
1 L$
t
� a
s'
- E F
0 :$
M
F250 Sao 1.000 Fee! �
Err in rin
Figure 3 -2. Diffuser Layout and Reservoir Test Points
3.2 Diffuser Tests
Several diffuser tests were performed from August 8 -12 to demonstrate the oxygenation capability of the
system over a wide range of operating conditions. Tables 3.1 through 3.4 present the sequence of tests
that were performed over this time period. In summary, the first day of testing involved acquiring
forebay and tailrace DO measurements with no oxygen flow from the diffuser system and with turbine
aeration turned off. For the second day of testing, the diffuser was operated while turbine aeration was
off. For the following three days various combinations of diffuser flow rates with turbine aeration from
various generating units were implemented.
3.2.1 Instrumentation
In the tailrace, measurements of the DO for each individual unit were obtained using a boat to maneuver a
DO probe directly into the outflow of the unit. Continuous recording DO probes were deployed adjacent
to the USGS compliance location on the NC Highway 731 Bridge pier, and in the west channel of the
tailrace. Tailrace monitoring locations are shown in Figure 3 -3.
In the reservoir, water quality profiles were taken at the seventeen locations shown in Figure 3 -2. A
Seabird Electronics SBE 19plus high- resolution profiler (CTD) with optional SBE 43 dissolved oxygen
sensor, having a response time of 1.4 seconds at 20 °C, was used to collect conductivity, temperature,
depth, and DO data at a 4 Hz sampling rate.
28

Tailrace Oxygen Diffuser Test Stations
Figure 3 -3. Tailrace Monitoring Stations for Oxygen Diffuser Tests
3.3 Results
Time series charts and contour plots are presented to demonstrate the DO improvements that the Tillery
oxygen diffuser system provided in the tailrace and reservoir forebay. A summary of the test results are
presented in this section. Figures 3 -4 through 3 -8 present time series plots of tailrace DO concentrations
for each day of testing. In addition to DO concentrations, these plots also show the total project and
individual unit flow rates, and the oxygen flow rates for the diffuser system. On the first day of the test,
the power plant turbines were operated on a normal operating schedule without oxygenation to provide
background DO values in the reservoir forebay and tailrace. Figure 3 -4 shows that there is initially a high
DO concentration (10.0 mg /L) due to photosynthesis of the large amount of aquatic plants in the tailrace.
At the peak turbine operation of approximately 17,000 cfs, the tailrace DO reaches a minimum of 2.8
mg /L.
On the second day of the test, power plant turbines were scheduled to operate the same as on August 8.
However, the testing schedule was altered due to an outage of Unit 4. The oxygen diffuser system was
operated with the start of the available generating units. The oxygen flow was set to provide
approximately 2.4 mg /L of DO increase, based on the instantaneous water flow as calculated from the
total unit power. A programmable logic controller adjusted the total oxygen flow, as needed, and
provided the desired flow rate and distribution of oxygen to the four diffusers in the reservoir in the order
chosen by the operator. Since the reservoir forebay was not oxygenated at the initiation of hydro
29

generation operations, the diffuser release of DO started out at levels similar to or lower than that
measured on the previous day of testing. Figure 3 -5 shows that the DO increased throughout the
generation period. Unit 2 started at about 1.7 mg /L and increased to 4.3 mg/L over the course of the day.
Unit 3 started at 2.3 mg /L and increased to 3.5 mg /L. Unit 1 started at 2.9 mg/L and increased to
4.7 mg /L.
Figure 3 -6 presents results from the third day of testing when the power plant turbines were scheduled to
provide several different unit combinations for DO enhancement verification. Two draft tube venting
tests were also scheduled. Unit 1 operating alone started at 3.6 mg /L and increased to 4.7 mg /L with
turbine venting. With Unit 1 and Unit 2 in operation, Unit 1 started at 4.3 mg/L and increased to 5.1
mg /L with turbine venting. Unit 2 started at 4.1 mg/L and increased to 4.7 mg /L with turbine venting.
During generation, oxygen was built up in the forebay due to operation of the oxygen system. After
approximately 5 hours of operation, Units 2 and 4 were both maintaining 5.0 mg /L without turbine
venting. After approximately 7 hours of operation, Units 1 and 2 were close to 6.0 mg/L and Unit 4 was
4.8 mg /L. DO levels of 5.0 mg/L were maintained at the compliance point for most of the hydro
generation period.
Figure 3 -7 presents results from the fourth day of testing when several additional unit combinations were
operated. The oxygen flow rate was turned up on the diffuser system to add approximately 3.0 mg /L to
the hydro turbine flow so that the oxygen system maximum design flow could be tested during the
operation of all four units. Two turbine venting tests were also scheduled. Unit 3 operating alone started
at 4.5 mg/L and increased to 5.4 mg/L with turbine venting. With Units 2 and 3 in operation, Unit 3
maintained a DO concentration of 5.0 mg /L and Unit 2 maintained the DO at 5.8 mg /L without turbine
venting. With Units 3 and 4 in operation, Unit 4 maintained the DO at 5.0 mg/L. Unit 3 maintained 6.2
mg /L without turbine venting and 6.6 mg /L with turbine venting. With the higher initial DO
concentrations in the reservoir, DO levels of 5.0 mg/L or above were maintained at the compliance point
throughout the generation period.
The non - uniform DO concentration in the units was produced by the lateral distribution of DO in the
forebay, which is shown in Figure 3 -9. The DO concentration is higher near the river channel, which
produces a higher DO in Unit 3 because the intake for that particular unit is near the riverbed.
Figure 3 -8 presents the results for the fifth day of testing when additional unit combinations were
operated. The oxygen flow rate was turned down to add approximately 2.0 mg /L to the hydro turbine
flow because downstream DO levels exceeded desired levels on August 11. A turbine venting test was
also scheduled. Unit 4 operating alone maintained 5.7 mg /L. With Unit 1 and Unit 4 in operation, the
DO concentration was about 6.0 mg /L. With Units 1 and 3 in operation, the DO concentration was
approximately 6.0 mg /L without turbine venting and 6.4 mg /L with turbine venting. With all three units
in operation, the DO concentrations were again non - uniform with Unit 1 considerably higher than Unit 4.
During the fifth test day, DO concentrations of 5.0 mg /L or above were maintained at the compliance
point for all of the hydro generation period.
Figures 3 -10 through 3 -14 present DO and temperature contours along the transect defined by points B -E-
H-K-Q, which are shown in Figure 3 -2 with point B located closest to the Tillery Dam. The figures
present the DO concentrations that occurred after each day of testing. A continual increase of DO can be
seen as the tests progress through time. After the second day of testing, a maintenance oxygen flow of
300 scfm was implemented to eliminate any time lags in meeting the compliance at the bridge when the
turbines were started.
30

These figures clearly demonstrate a continual DO increase in the forebay as the diffuser operated during
the testing sequence. For example, on the first day of testing, reservoir DO is low and consistently below
2.0 mg /L below elevations of 260 ft. By the last day of testing the DO exceeds 4.0 mg /L at elevations
above 220 feet, which are next to the dam. The diffuser system provided sufficient oxygen to increase the
reservoir forebay DO concentration so that the tailrace DO compliance levels can be achieved.
As part of the diffuser system tests, the oxygen demand was measured over a short term (2 -hr) and longer
term (24 -hr) period to evaluate the Instantaneous Oxygen Demand (IOD) and the Biological Oxygen
Demand (BOD). Table 3.6 presents the results of these measurements. The IOD is consistently near zero
before and after oxygenation with a small decrease that occurs because of oxygenation. The BOD was
reduced at location E and throughout the tailrace as a result of oxygenation. As a result of these empirical
tests, the IOD was set to zero and the BOD was set to 0.5 in the oxygen diffuser system aeration model.
3.4 Summary and Conclusions
Oxygen diffuser system tests were performed on August 8 -12, 2011 to validate system performance to
achieve the DO compliance target levels during power plant generation. These tests collected DO data in
both the reservoir forebay and downstream tailrace. Several combinations of unit flows and diffuser
oxygen flow rates were tested to demonstrate the diffuser system performance over a wide range of power
plant operating conditions. In addition, turbine venting tests were also performed to evaluate the additive
effects of venting to DO levels.
The initial DO concentration in the reservoir forebay was low (2.0 mg /L or less) and produced tailrace
DO concentrations of less than 3.0 mg /L as measured at the DO compliance point at the NC Highway 731
Bridge. During the course of testing with sustained operation of the oxygen diffuser system, the reservoir
forebay DO concentration increased to levels that exceeded 5.0 mg /L over a large area of forebay
elevations adjacent to the Tillery Dam. From the third through the fifth day of testing, the tailrace DO
concentrations at the compliance location consistently exceeded 5.0 mg /L while the power plant turbines
were operating. Therefore, these verification tests demonstrated that the oxygen diffuser system is
capable of providing sufficient DO levels for the Tillery Development to meet the target DO compliance
during power plant generation.
31

Table 3.1. Oxygen Diffuser Test Matrix 8/8/2011
Progress Energy
Dissolved Oxygen Enhancement Verification Trials
August 8, 2011
Test No.
Start
Time
End
Time
Unit #
Comment
Flow
(cfs)
Turbine
Venting
Target
Delta DO
(mg/L)
oxygen
(scfm)
Flow per Diffuser
1
2
3
4
None
0:00
7:00
None
N/A
N/A
N/A
0
T8 -0
7:00
11:50
None
1
N/A
N/A
N/A
0
610
610
T8 -1
11:50
13:00
1,3
7,226
Off
N/A
0
599
599
T8 -2
13:00
13:42
2,4
Unit 4 trip
7,048
Off
N/A
0
329
329
T9 -3
13:42
14:00
2,
2,818
Off
N/A
0
559
559
T8 -3
14:00
14:45
2,3
6,431
Off
N/A
0
526
526
526
14:45
15:00
2, 3, 4
10,661
1 Off
N/A
1 0
1 407
1
1 407
1 407
T8 -4
15:00
17:15
2, 4, 3, 1
14,274
Off
N/A
0
1 150
1
1
150
None
17:15
23:59
None
N/A
N/A
N/A
0
Table 3.2. Oxygen Diffuser Test Matrix 8/9/2011
Progress Energy
Dissolved Oxygen Enhancement Verification Trials
August 9, 2011
Test No.
Start
Time
End
Time
Unit #
Comment
Flow
(cfs)
Turbine
Venting
Target
Delta DO
(mg/L)
Oxygen
(scfm)
Flow per Diffuser
1
2
3
4
T9 -0
0:00
12:00
None
N/A
T9 -1
12:00
13:00
1,3
1
7,226
Off
2.4
1 1,220
610
610
T9 -2
1 13:00
13:40
2,4
7,048
Off
2.4
1,197
599
599
13:40
14:00
2
unit 4 trip
2,818
Off
2.4
659
329
329
T9 -3
14:00
15:00
2,3
6,431
Off
2.4
1,118
559
559
T9 -4
15:00
17:00
2, 3, 1
10,044
Off
2.4
1,578
526
526
526
17:00
18:00
1 1,3
7,226
Off
2.4
1 1,220
1 407
1
1 407
1 407
T9 -5
17:00
23:59
None
N/A
N/A
1
1 300
1 150
1
1
150
32

Table 3.3. Oxygen Diffuser Test Matrix 8/10/2011
Progress Energy
Dissolved Oxygen Enhancement Verification Trials
August 10, 2011
Test No.
Start
Time
End
Time
Unit #
Comment
Flow
(cfs)
Turbine
Venting
Target
Delta DO
(mg /L)
Oxygen
(scfm)
Flow per Diffuser
1
2
3
4
T10 -0
0:00
12:00
None
N/A
N/A
1
300
150
150
T10 -1
12:00
12:30
1
3,613
Off
2.4
655
327
75
75
327
T10 -2
12:30
13:00
1
3,613
On
2.4
655
327
327
T10 -3
1 13:00
13:30
1,2
6,431
Off
2.4
1,118
559
559
T10 -4
13:30
14:00
1,2
6,431
On
2.4
1,013
507
441
507
T10 -5
14:00
16:00
2,4
7,048
Off
2.4
1,226
409
409
409
T10 -6
16:00
18:00
1, 2, 4
10,661
Off
3
1,891
473
473
473
473
T10 -7
18:00
20:00
None
I
N/A
N/A
1
300
75
1 75
75
1 75
T10 -7
20:00
21:00
1,2,314
emergency
operation
14,274
Off
1
300
75
75
75
75
T10 -7
21:00
23:59
Crest Gate
N/A
N/A
1
300
75
75
75
75
CG5
19:00
23:59
Crest Gate
330
Table 3.4. Oxygen Diffuser Test Matrix 8/11/2011
Progress Energy
Dissolved Oxygen Enhancement Verification Trials
August 11, 2011
Test No.
Start
Time
End
Time
Unit #
Comment
��fs
Turbine
Venting
Target
Delta DO
(mg /L)
oxygen
(scfm)
Flow per Diffuser
1
2
3
4
CG5
0:00
8:00
Crest Gate
330
T11 -0
0:00
13:00
None
N/A
N/A
1
300
75
75
75
75
T11 -1N
13:00
13:30
3
3,613
Off
3
875
437
437
T11 -1A
13:30
14:00
3
3,613
On
3
875
437
437
T11 -2
14:00
15:00
2,3
6,431
Off
3
1,323
441
441
441
T11 -3N
15:00
15:30
3,4
7,843
Off
3
1,548
516
516
516
T11 -3A
15:30
16:00
3,4
7,843
On (3)
3
1,548
516
516
516
T11 -4
16:00
17:00
1, 2, 3, 4
14,274
Off
3
2,571
643
643
643
643
T11 -5
17:00
23:59
None
N/A
N/A
1
300
150
150
CG6
17:00
23:59
Crest Gate
330
33

Table 3.5. Oxygen Diffuser Test Matrix 8/12/2011
Progress Energy
Dissolved Oxygen Enhancement Verification Trials
August 12, 2011
Test No.
Start
Time
End
Time
Unit #
Comment
Flow
(cfs)
Turbine
Venting
Target
Delta DO
(mg /L)
Oxygen
(scfm)
Flow per Diffuser
1
2
3
1 4
CG6
0:00
7:30
Crest Gate
330
T12 -0
0:00
7:30
None
N/A
N/A
1
300
150
150
T12 -0
7:30
13:00
None
N/A
N/A
1 0.5
150
150
T12 -1
13:00
14:00
4
4,230
Off
2
679
1 339
339
T12 -2
14:00
15:00
1,4
7,843
Off
2
1,062
531
531
T12 -3N
15:00
15:30
1,3
7,226
Off
2
996
498
498
T12 -3A
15:30
16:00
1,3
7,226
On
2
996
498
498
T12 -4
16:00
17:00
1, 3, 4
11,456
Off
2
1,445
482
482
482
T12 -5
17:00
23:59
None
N/A
N/A
0.75
230
230
34

Tillery Dam - [Test T8) - Tailrace
ADO - USGS site — DO West Channel USGS D0 v Unit 7
• Unit 2 • Unit 3 ■ Unit4 —Zero DO
Station Flow USGS stage tDiffuser 02 Flow
12
48,000
11
44,000
10
40,000
9
m
8
36,000
J
U]
p�
32,000 c
� 6
�
5
28,040 p
tT
�
0 4
24,000
3
20,000
O 2
�
w 1
16,000
0
12,000
1
8,000
_2
4,000
-3
-4
0
10:00 12.00 14:00 16:00 18:00 20:00 22:00 0:00
8:00
Figure 3 -4. Turbine Operations and Tailrace DO Measurements 8/8/2011
Tillery Dam - (Test T9) - Tailrace
—DO - USGS site ADO Wesl Channel USGS DO • Unit 1
• UnA 2 ■ Unil3 . Unil4 —Zero DO
�Slaldw flow USGSBWe tDiHuser 02 Flow
12 48,000
11
44,000
10
40,000
8 36,000
7 u]
32,000
�s ro
5 28,000 3p
m
ILL
s 4 24,000
U 01, m
3 20,000
0 2 a
N 1 16.000
O
D 12,000 y
-1 7
8,000
-z
3 4,000
8.00 14:00 12.00 14.00 16:00 18:00 20:00 22:00 4:00
Figure 3 -5. Turbine Operations and Tailrace DO Measurements 8/9/2011
35

Figure 3 -6. Turbine Operations and Tailrace DO Measurements 8/10/2011
rigure s -i. iurbme uperations ana iaiirace liu > veasurements b/iii.Luii
W:
Tillery Dam - (Test T10) - Tailrace
—DO - J-DGS s@e
—DO West Channel —l1SGS DO
• Unil7
■ Unit2
A JmI3 . Jnil4
—Zero DO
— Slalion Flow
USGS stage tDiffusGr02 Flow
t Crest Gala Flow
12
48,000
11
aa.000
10
40,000
9
d
8
36.000 m
Co
J
7
32,000 'v
6
—
Cz
m
5
+
23,000 c
rn
+
+
LL
4
-
24,000
d3
O7
20,000
O
2
p
N
16,000
1
0
12,000
-1
8,000
-2
4.000
3
800
10:00 1200
1400 16:00 18-00 20 -00
22 -00 0 -00
Figure 3 -6. Turbine Operations and Tailrace DO Measurements 8/10/2011
rigure s -i. iurbme uperations ana iaiirace liu > veasurements b/iii.Luii
W:

Figure 3 -8. Turbine Operations and Tailrace DO Measurements 8/12/2011
W
❑Ishanne ELF
Figure 3 -9. Lateral DO and Temperature Contours in Tillery Forebay 8/11/2011
37

0
0
W
0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000
Distance (ft)
Figure 3 -10. Longitudinal DO and Temperature Contours in Tillery Forebay 8/8/2011
Az
3
g
Figure 3 -11. Longitudinal DO and Temperature Contours in Tillery Forebay 8/9/2011
38

Distance (ft)
Figure 3 -12. Longitudinal DO and Temperature Contours in Tillery Forebay 8/10/2011
Distance (ft)
Figure 3 -13. Longitudinal DO and Temperature Contours in Tillery Forebay 8/11/2011
39

❑iatane (t
Figure 3 -14. Longitudinal DO and Temperature Contours in Tillery Forebay 8/12/2011
40

Table 3.6. Instantaneous Oxygen Demand and Biological Oxygen Demand Test Results
Location
Sample Collection
Date /Time
Sample Depth
(m)
In Situ - DO
(mg /I)
2 hr
02 Demand
(mg /l)
24 hr
02 Demand
(mg /l)
Tailrace
7/18/1111:45
0.3
0.09
0.99
E-- foreba
7/18/111015
17.1
0.09
0.02
-0.12
E-- foreba
7/18/111015
18.2
0.09
0.01
-0.03
E-- foreba
7/18/111015
19.2
0.09
1 0.00
0.09
E-- foreba
7/18/111015
20.1
0.09
0.00
0.28
E-- foreba
7/18/111015
21.1
0.09
0.00
0.10
Test T1 -1 Unit
7/20/111341
0.3
2.56
0.04
0.48
Test T1 -1 Unit
7/20/111344
0.3
3.21
0.05
0.55
Test T1 -3 Bride
7/20/111658
0.3
3.50
0.05
0.53
Test T1-3 Unit 3
7/20/111652
0.3
3.04
0.06
0.65
Test T1 -3 Unit 1
7/20/11 1648
0.3
2.55
0.07
0.61
Test T1 -2 Bride
7/20/111540
0.3
3.20
1 0.07
0.65
Test T1 -1 Bride
7/20/111350
0.3
3.70
0.03
0.53
Test T2-1 Unit
7/21/111339
0.3
5.67
0.04
0.48
Test T2-1 Unit
7/21/111344
0.3
4.83
0.05
0.55
Test T2-3 Bride
7/21/111530
0.3
5.20
0.05
0.53
Test T2-3 Unit 3
7/21/111508
0.3
5.30
0.06
0.65
Test T2 -3 Unit 1
7/21/11 1513
0.3
6.34
0.07
0.61
Test T2-2 Bride
7/21/111425
0.3
5.30
0.07
0.65
Test T2-1 Bride
7/21/111350
0.3
5.30
1 0.03
0.53
Test T3 -1 Unit
7/22/111242
0.3
3.94
0.10
0.71
Test T3 -1 Unit
7/22/111245
0.3
4.19
0.11
0.83
Test T3 -3 Bride
7/22/11 1555
0.3
5.20
0.10
0.82
Test T3 -3 Unit 3
7/22/11 1540
0.3
4.98
0.10
0.79
Test T3 -3 Unit 1
7/22/11 1545
0.3
6.34
0.12
0.85
Test T3 -2 Bride
7/22/11 1445
0.3
5.30
0.12
0.93
Test T3 -1 Bride
7/22/11 1255
0.3
4.80
0.10
0.82
E-- foreba
8/3/111200
17.2
0.09
0.04
0.31
E-- foreba
8/8/111200
18.3
0.09
-0.01
0.21
E-- foreba
8/8/111200
19.3
0.09
0.03
0.35
E-- foreba
8/8/111200
20.2
0.09
0.06
0.40
E-- foreba
8/8/111200
21.2
0.09
0.00
0.27
Falls Tailrace
8/4/2011 14:41
0.3
5.22
0.02
0.16
E-- foreba
8/8/111200
17.2
0.09
0.70
E-- foreba
8/8/111200
18.3
0.05
0.69
E-- foreba
8/8/111200
19.3
0.07
0.88
E-- foreba
8/8/111200
20.2
0.08
1.19
E-- foreba
8/8/111200
21.2
0.04
0.97
USGS Site
8/8/2011 15:30
0.3
2.8
0.05
0.49
Unit 4
8/8/2011 15:12
0.3
2.81
0.03
0.48
Unit 3
8/8/2011 15:17
0.3
2.77
0.04
0.41
Unit 2
8/8/2011 15:22
0.3
2.69
0.04
0.40
Unit 1
8/8/2011 15:26
0.3
2.75
0.02
0.29
Q- -above diffusers
8/11/1121:29
15.4
-0.07
0.00
Q- -above diffusers
8/11/1121:29
16.4
-0.01
-0.07
Q- -above diffusers
8/11/1121:29
17.4
0.01
0.01
Q- -above diffusers
8/11/1121:29
18.4
0.01
0.15
Q- -above diffusers
8/11/1121:29
19.4
0.01
0.14
E-- foreba
8/11/1121:09
17.2
0.05
0.49
E-- foreba
8/11/1121:09
18.3
0.05
0.57
E-- foreba
8/11/1121:09
19.3
0.06
0.57
E-- foreba
8/11/1121:09
20.2
0.06
0.57
E-- foreba
8/11/1121:09
21.2
1 0.12
1.11
USGS Site
8/11/2011 16:57
0.3
5.3
-0.01
0.06
Unit
8/11/201116:47
0.3
4.45
0.00
0.03
Unit
8/11/201116:51
0.3
6.44
0.02
0.31
Unit
8/11/201116:54
0.3
7.39
0.02
0.30
Unit 1
8/11/2011 16:57
0.3
6.94
0.01
0.20
Q- -above diffusers
8/19/11 945
15.4
0.11
-0.02
0.00
Q- -above diffusers
8/19/11 945
16.4
0.1
0.04
0.15
Q- -above diffusers
8/19/11 945
17.4
0.1
0.06
0.35
Q- -above diffusers
8/19/11 945
18.4
0.1
0.04
0.34
Q- -above diffusers
8/19/11 945
19.4
0.1
0.07
0.45
E-- foreba
8/19/111015
17.2
0.14
0.02
0.02
E-- foreba
8/19/111015
18.3
0.14
0.09
0.31
E-- foreba
8/19/111015
19.3
0.11
0.20
0.97
E-- foreba
8/19/1110:15
20.2
0.11
0.19
0.90
E-- foreba
8/19/111015
21.2
0.1
0.23
1.12
Avera es
0.05
0.48
Medians
0.05
0.49
41

4.0 CREST GATE OPERATIONS
The crest gate at Tillery will be used to provide minimum flow releases under the new FERC license
requirements from the hydroelectric development. The crest gate is shown in Figure 4 -1, and design
parameters are given in Table 4.1. The crest gate is located adjacent to the powerhouse on the east side of
the dam.
4.1 Test Procedure
The crest gate was tested for aeration effectiveness during seven non - generation periods in August 2011.
The released minimum flow was the same for each test, approximately 330 cfs. The 330 cfs minimum
flow is specified in the North Carolina 401 Water Quality Certificate (NCDWQ 2008) and is expected to
be included in the new FERC license requirements, once issued. The DO concentration of the crest gate
flow was computed by averaging the DO concentration in the top 3 meters (9.8 ft) of the reservoir surface
water from vertical profile data that were obtained when these minimum flow tests were performed. The
DO measurements at the NC Highway 731 Bridge were used to evaluate the overall effectiveness of the
crest gate flows. Monitoring station locations for crest gate testing are shown in Figure 4 -2.
4.2 Results
The results of these minimum flow tests are presented in Figure 4 -3. All of the test results showed a
significant improvement in the tailrace DO concentrations by using the crest gate to supplement tailwater
flow. On evenings when the crest gate was not used, minimum DO levels dropped to 2.0 to 3.0 mg /L.
However, when the crest gate was opened soon after generation stopped, the minimum DO was 4.0 mg/L.
These tests indicate that if crest gate flows are delayed by more than two hours, the DO may fall below
4.0 mg /L at the compliance location.
By comparing the DO concentration in the crest gate releases to the DO concentration measured at the
compliance point, the effects of respiration and photosynthesis dynamics of aquatic plants in the tailrace
can be ascertained. Figure 4 -3 shows that water flowing through the crest gate has a DO concentration
that exceeds 7.0 mg /L while the DO at the compliance location periodically approaches 2.0 mg /L. The
DO effects of crest gate operation can also be seen in Figure 4 -3. The minimum DO falls between 2.0
and 3.0 mg/L on evenings when the crest gate was not operated, while the minimum DO is increased to
4.0 mg /L on evenings when the crest gate was operated.
The detailed plots in Figures 4 -4 and 4 -5 show the tailrace DO concentrations with the crest gate
operating on two and three evenings, respectively. Three distinct periods are observed for the daily
cycles:
1. Low Flow Period with Algal Respiration in the Early Morning Hours — Water flow for this
cycle is low and is provided either by leakage flows from the dam (from leaking tainter wicket
gates) or from minimum flow provided by the crest gate. With the low flow, aquatic plant
respiration dominates the DO that approaches 2.0 mg /L at night unless the crest gate is open,
during which the minimum DO is 4.0 mg /L.
Late Morning Low Flow Period with Photosynthesis before Turbine Generation Starts —
During this period, supersaturated levels of DO occurred due to aquatic plant photosynthetic
activity.
High Flows During the Afternoon Generation Period — During this period, the DO
concentration in the generation flows dominate the DO measured at the compliance location. The
42

DO measured at the compliance point is a function of the DO concentration in the turbine
withdrawal zone of the reservoir forebay and of the DO increase provided by turbine venting.
The oxygen diffuser system plays a primary role during this period by ensuring that the DO
concentration flowing into the turbines is high enough for the turbine venting to achieve the target
DO. DO is not measurably affected by aquatic plant photosynthesis during high generation
flows.
Figure 4 -6 shows results from tests previously conducted by Progress Energy during August 2008. These
results show that minimum DO levels were affected in a manner similar to the more recent tests.
Figure 4 -1. Tillery Crest Gate
43

Table 4.1. Crest Gate Design Parameters
DESIGN PARAMETERS:
CLEAR WATERWAY WIDI.1
VERTICAL GATE HEIGHT;
CREST ELEVATION - GATE FULL UP; 239,45'
• GREST ELEVATION - GATE DOWN; 231,59
r NORFIAL WATER LEVEL; I PLEASE PROVIDE
• DESIGN WATER LEVER; 234,46'
+ TIME TO OPEN OR CLOSE. 15 MIN MINIMUM
Tailrace Creat Gate Test Stations
Figure 4 -2. Monitoring Stations for Crest Gate Tests
44

Tillery Tailrace Dissolved Oxygen and Crest Gate Operation
USGS DO ■ Crest Gate Oxygen Crest Gate Spill
IL
11
10
9
rn 8
E
c 7
v
rn
X
O 6
'O
> 5
O
N
0 4
3
2
1
0
I UUU
900
800
700
600 N
U
3
500 O
LL
400 U)
300
200
100
0
oP P ryP �P �P yP 6P P
ti ti ti ti ti ti ti ti
2011
Figure 4 -3. Tailrace Dissolved Oxygen and Crest Gate Operation, August 2011
12
11
10
9
m 8
c 7
v
a
O 6
'O
> 5
0
N
N 4
0
3
2
1
0
O�
^O'
\ ^O
0
Tillery Tailrace Dissolved Oxygen and Crest Gate Operation
-USGS DO ■ Crest Gate Oxygen Crest Gate Spill
1000
900
800
700
600 w
500 0
LL
400 N
300
200
100
0
ti
2011
Figure 4 -4. Tailrace Dissolved Oxygen and Crest Gate Operation for a Two Day Interval
45
I
I
I I
I
I
■ %
■
■
I
I
I I I
I I■
■ I
I
I
I I I
I I
I
I I
I I
I I
I I
I I
I I
I
I I
I
I
I
I
I
I
I I
I I
I
I I
I
I I
I I
I
1000
900
800
700
600 w
500 0
LL
400 N
300
200
100
0
ti
2011
Figure 4 -4. Tailrace Dissolved Oxygen and Crest Gate Operation for a Two Day Interval
45

Tillery Tailrace Dissolved Oxygen and Crest Gate Operation
—USGS DO ■ Crest Gate Oxygen Crest Gate Spill
12
11
10
9
m 8
E
c 7
v
a
O 6
'O
5
0
N
N q
0
3
2
1
0
1000
900
800
700
600 m
v
500 0
LL
400 n
300
200
100
0
0 0 0
2011
Figure 4 -5. Tailrace Dissolved Oxygen and Crest Gate Operation for a Three -Day Interval
12.0
10.0
8.0
m
6.0
O
0
4.0
2.0
DO and Flows
—DO TYCM1 -2 (Center) - DO TYCM1 -1 (East) DO TYCM1 -3 (West) Spill Flow Turbine Flow
30,000
25,000
20,000
N
15,000
3
0
LL
10,000
5,000
0.0 0
08/13/0817:27 08/14/0817:27 08/15/0817:27 08/16/0817:27 08/17/0817:27 08/18/0817:27 08/19/0817:27
r scroll Data Timestamp rx -Mls wale
Figure 4 -6. Tailrace Dissolved Oxygen and Crest Gate Operation, August 2008
I

5.0 DEVELOPMENT AND CALIBRATION OF THE TILLERY TURBINE AERATION
MODEL
A turbine model was created for the Tillery units to predict the quantity of air flow that each unit provides
and the according DO increase in the unit discharge. A DBM is the primary component of the turbine
aeration model which predicts the DO increase for a given air flow into a unit. The DBM is a first -order
gas transfer model [Ruane and McGinnis 2007]. Turbine aeration models, based on the DBM, have been
successfully implemented at several hydro plants at which turbine aeration was applied to enhance the
DO of the turbine discharge.
An important consideration for the turbine aeration model is that it is appropriately calibrated to tailor it
to the unique characteristics of each unit. The results of the air flow and tailrace DO testing that were
previously described (see Section 2) were used to calibrate both the air flow for each unit and the
according DO increase that the air flow for a given unit provides. Details of the DBM calibration are
presented below.
5.1 Background
The DBM is the foundation of the turbine aeration model that was used at Tillery. The model predicts gas
transfer (both dissolution and stripping of gases) across the surface of individual bubbles and
simultaneously tracks both gaseous (bubble) and dissolved nitrogen and oxygen.
Because the DBM is based on fundamental principles, it can be tailored for use in various aeration models
that cover several applications. Examples of these applications include bubble -plume diffusers
[McGinnis et al. 2004; 7 Wuest et al. 1992], side - stream super saturation systems for rivers, and turbine
aeration units. The DBM approach was first used by REMI in 2003, on the Saluda Project, with excellent
results and has since been successfully applied to over 20 hydropower plants.
DBM turbine aeration applications are based on the following assumptions
The bubbles are produced at a constant rate, and remain uniformly distributed across the draft
tube.
Both water and bubbles are in plug flow, with negligible dispersion.
3. No bubble coalescence occurs; that is, N, the number of bubbles per second, remains constant.
4. For a given set of boundary conditions, the bubbles produced are uniform in size.
5. Temperature is assumed constant throughout the draft tube and tailrace.
5.2 Calibration Procedure
The calibration procedure for the turbine aeration model consists of the following steps:
1. The geometry of the draft tube is developed and incorporated into the DBM program.
2. The tailwater elevation versus project flow is added to the model.
Airflow lookup tables are created for each unit. These are used to compute the quantity of
airflow that a unit provides given the unit flow rate and tailwater elevation.
47

Using measured inflow and outflow DOs, measured airflow, temperature, turbine flow, and
tailwater elevation, the model is iteratively run to determine the bubble size that most closely
yields the measured DO.
Additional key characteristics and assumptions in the Tillery Turbine Aeration Model include the
following items:
1. The tailwater elevation (TWE) is assumed to vary as a polynomial function of flow rate. The
tailwater polynomial for Tillery is shown in Figure 5 -1.
2. Lookup tables were used to accurately characterize unit air flows as a function of unit water flow
rate and TWE.
3. Each unit is assumed to have the same bubble size versus unit flow relationship.
4. Dissolved nitrogen is assumed to be 105% saturated.
5. There are no air controls on the model. Unit air flow control valves are either fully open or fully
closed.
5.3 Calibration Data and Results
The calibration data was provided by various turbine aeration tests conducted at Tillery (ARCADIS
2010a; ARCADIS 2010b). A preliminary calibration was performed based on aeration tests conducted at
Tillery in 2008. The model was further tuned to accurately reflect the results from the aeration tests
performed on August 2 -5, 2011.
The tailwater elevation versus project flow used in the model is presented in Figure 5 -1. This is based on
data acquired during the August 2011 turbine aeration tests and archival data for plant operations.
Figures 2 -4 through 2 -7 present the test results for the individual unit air flows. These data were used to
derive air flow lookup tables for the model. Figures 5 -2 through 5 -5 present the air flow as computed
from the lookup tables for the DO tests that were conducted in August 2011.
The bubble size relation required to best fit the DO data for each unit is presented in Figure 5 -6. The
polynomial fit also shown in this figure was used to represent the bubble size versus flow rate for each
unit.
Figure 5 -7 presents the model predictions versus measured data for the recent turbine aeration tests. The
predicted DO for Units 1, 2, and 4 agrees closely with the measured DO. The predicted DO for Unit 3
falls outside of the 10% error band. During the calibration procedure, it was determined that an
unrealistic bubble size relationship would have been required to improve this calibration. A possible
explanation for this discrepancy is that the simplified model flow does not adequately represent the actual
flow patterns through the draft tube, which produces a discrepancy between the model residence time and
the actual residence time. This could cause the DO from Unit 3 to be biased low and would bias the
estimated oxygen use for the diffuser to be high. Because the turbine aeration provides a small portion of
the total oxygen required for compliance, and because this bias exists in only one unit, this will produce
an insignificant error in the calculations to predict maximum oxygen flow rates and total oxygen required
for the diffuser system.
48

5.4 Summary and Conclusions
A turbine aeration model for Tillery Units 1 -4 was created and calibrated to predict the DO increase in the
turbine discharges that aeration provides. The calibration data and results are presented. The actual air
flow agrees closely to the model air flow contained in the lookup tables. The predicted DO agrees closely
to the measured DO for Units 1, 2, and 4. The DO for Unit 3 is biased low, which will cause the model to
under predict the DO increase resulting from turbine aeration. Because the oxygen provided by the
turbines is much less than the turbine provided by the diffusers, the effect of the bias on the system
aeration results will be negligible.
Figure 5 -1. Polynomial Fit for Tailwater Elevation vs Project Flow
t Measured Air Flow t Model Air Flow
40 40
35 35
30 30
N
y 25 25
3 20 20
O
LL 15 15
L
a 10 10
5 5
0 0
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Unit Water Flow (cfs)
Figure 5 -2. Unit 1 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011
49

Figure 5 -3. Unit 2 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011
t Measured Air Flow Model Air Flow
30 30
25 25
20 20
v
3 15 15
O
LL
L 10 10
a
5 5
0 1 0
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Unit Water Flow (cfs)
Figure 5 -4. Unit 3 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011
50
t Measured Air Flow a Model Air Flow
25
25
20
20
N
15
15
3
0
LL
10
10
L
'a
5
5
0
0
0 500 1000 1500 2000 2500 3000 3500
4000
Unit Water Flow (cfs)
Figure 5 -3. Unit 2 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011
t Measured Air Flow Model Air Flow
30 30
25 25
20 20
v
3 15 15
O
LL
L 10 10
a
5 5
0 1 0
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Unit Water Flow (cfs)
Figure 5 -4. Unit 3 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011
50

Figure 5 -5. Unit 4 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011
2.1
t Measured Air Flow @ Model Air Flow
90
90
80
80
1.9
70
RZ = 0.9846
70
60
60
v
50
Unit 1
50
3
£
1.7
40
40
LL
E
L
30
30
a
20
20
1.5
10
10
'v
R
0
0
0 1000 2000 3000 4000 5000 6000
`y
Unit Water Flow (cfs)
Figure 5 -5. Unit 4 Air Flow Lookup Table Fit to Data Acquired During the Turbine DO Uptake
Testing Conducted August 5 -8, 2011
Figure 5 -6. DBM Calibration of Bubble Size versus Unit Flow Rate
51
2.1
�
■
�
�
Unit 2
Unit 3
Unit 4
Bubble curve
1.9
RZ = 0.9846
Unit 1
£
1.7
E
1.5
'v
R
`y
1.3
1.1
R
0.9
0.7
0.5
1500
2000
2500 3000 3500
4000 4500
Unit flow rate (cfs)
Figure 5 -6. DBM Calibration of Bubble Size versus Unit Flow Rate
51
�
■
�
�
Unit 2
Unit 3
Unit 4
Bubble curve
RZ = 0.9846
Figure 5 -6. DBM Calibration of Bubble Size versus Unit Flow Rate
51

Figure 5 -7. Turbine Aeration Model Predicted DO versus Measured DO
(Dashed Lines are ±10 %)
52
6.0
♦Unit1
■Unit2
5.5
5.0
♦ Unit 4
4.5
rn
E
p
4.0
0
v
3.5
U
'v
3.0
♦ Unit 3
IL
2.5
AL
2.0
1.5
1.5 2.0 2.5
3.0 3.5 4.0 4.5
5.0 5.5 6.0
Measured DO (mg /L)
Figure 5 -7. Turbine Aeration Model Predicted DO versus Measured DO
(Dashed Lines are ±10 %)
52
♦Unit1
■Unit2
♦ ♦
♦ Unit 4
Figure 5 -7. Turbine Aeration Model Predicted DO versus Measured DO
(Dashed Lines are ±10 %)
52

6.0 TILLERY SYSTEM AERATION MODEL
A system aeration model was created to predict DO concentrations in the Tillery tailrace. The system
aeration model combines the effects of the reservoir forebay oxygenation, turbine aeration, crest gate
releases, and infrequent dam tainter gate spill releases. Five years of hourly archival data were used to
create input data for the model that included project flow rates, influent DO, and plant power production.
Based on these input data, the model determines whether the compliance targets can be achieved and how
to operate the various systems to achieve compliance.
6.1 Background
The three components in the system aeration model include the forebay oxygenation system, the turbine
aeration system, and the crest gate and dam tainter gate releases for minimum and bypass flows,
respectively. The system aeration model is a time invariant system, i.e., the solution at any time step does
not depend on the solution from the previous model time step. Specifically, the model does not include a
forebay or tailrace model to predict the time variant production and consumption of DO. The formulation
of the system aeration model is consistent with the scope of the current project and provides a framework
for predicting the effects of the different components on the tailrace DO.
As previously described, the reservoir oxygen diffuser system consists of four, 3,500 -ft line diffusers that
can provide a maximum oxygen flow rate of 150 tons /day. As the oxygen is released in the reservoir
forebay and dissolved, not all of it is drawn into the power plant turbines. Three factors are used to
determine how much oxygen is released or consumed in the reservoir forebay before being drawn through
the turbines. An oxygen transfer efficiency (OTE) of 85% is used to compute the amount of oxygen that
is dissolved in the forebay as a function of the total oxygen flow rate of the forebay diffusers. The
primary mechanism for the 15% oxygen loss is that the oxygen is released through the water surface
before it dissolves. As the oxygen is released in the forebay, both organic and inorganic components in
the reservoir are oxidized and consume oxygen before it is drawn into the turbines. Two factors are used
to represent these processes, which include an instantaneous oxygen demand (IOD) to model the short-
term consumptive processes and a biological oxygen demand (BOD) to represent the longer term
consumptive processes.
The OTE in conjunction with the IOD is used to predict the oxygen flow rate that is required to achieve
DO compliance. The maximum oxygen flow rate was used to determine the size of the reservoir forebay
oxygen diffuser system. The OTE determines the amount of oxygen dissolved in the water flowing
through the turbines versus the total amount of oxygen released in the reservoir. This was set to 85% for
Tillery, which is based on experience with several previous installations. For many installations, the DO
is further reduced because of short-term oxidation processes represented by the IOD. However, for the
Tillery diffuser system, field testing showed that the IOD was very small and was therefore not a factor
that affected the oxygen requirements of the system.
The BOD in conjunction with the OTE is used to determine the quantity of oxygen that will be required to
meet compliance. Typical operation of the reservoir forebay diffusers involves a continual flow of
oxygen that maintains the forebay DO at a prescribed level. This ensures that there will be sufficient DO
in the initial turbine releases at startup to meet compliance. Because the forebay diffuser maintains DO at
higher levels, longer term processes consume some of the DO, which is represented by the BOD. The
BOD was modeled by reducing the DO in the hourly flow rate by 0.5 mg /L, which was based on field
testing (see Section 3).
53

The Tillery system aeration model includes a turbine aeration component that is previously described in
Section 5. The turbine aeration model predicts the quantity of air drawn into each turbine and the
resulting DO levels in the individual turbine releases. The DO levels in the turbine releases are then
combined with the crest gate and infrequent dam tainter gate spill flow DO to provide the average DO
concentration for the project release into the tailrace. The turbine aeration model obtains the air flow
rates for the turbines by linearly interpolating data contained in lookup tables of air flow rate versus water
flow rate and tailwater elevation. The DO uptake is then computed by the BDM, which is based on a first
principles approach.
Bypass flows are an important component of Tillery operations with respect to the tailrace DO levels.
The bypass flows are produced by minimum flows through the crest gate and by higher, but infrequent
flow releases through the dam tainter gates. The crest gate flows were modeled by reviewing the archival
data and replacing all project flow rates of zero with 725 cfs during the fish spawning season (March 15th
to May 15th) and 330 cfs for all other times of the year. When a flow rate of zero was increased to 330 cfs
(or 725 cfs for spawning season) the flow rate in the following hour was decreased by the same amount to
maintain the same historical volumetric flow rate. The spill flow was only modified when it was
important for achieving DO compliance.
6.1.1 Input Data
The input data for the system aeration model were obtained from hourly plant operating data that
contained project flow rate, plant load, headwater elevation, and tailwater elevation versus time. These
data were then synchronized to water quality data measured at the NC Highway 731 Bridge (compliance
point) which provided DO concentration and temperature versus time. The bridge DO data were used to
represent the influent DO to the turbines. Archive data from 2005 and 2007 -2010 were used in the model.
In general, data from May 1st to October 31st were analyzed for these years (Progress Energy 2006c).
However, in 2008, the available data were from June 12th to October 15th. In 2006, there were insufficient
DO measurements to use for model input. For some months, there were several days for which archive
DO measurements were not available. The oxygen usage for these months was scaled by the number of
days for which data existed versus the number of days for which data did not exist to make the data
consistent on a year -to -year basis.
The DBM requires individual unit water flow rates to compute the air flow and DO uptake on a unit basis.
However, individual unit load information is not available in the Tillery hourly operating plant data.
Because actual data were not available, unit load information was computed from the plant load
information and the operating head by assuming the units were always historically dispatched in a
specified order as follows: Unit 2 being loaded first, followed by Unit 4, then Unit 3, and then Unit 1.
This is the typical dispatch order for Tillery operation. An optimized dispatch calculation procedure,
constrained by the specified unit order, was used to compute the unit load allocation for a given plant
load. The unit flow rates were then computed from the unit load, given the gross head for the given time
step, and from the unit characteristics.
6.1.2 System Aeration Model Assumptions and Rules
The system aeration model used the archival data in conjunction with the turbine aeration model and a set
of rules for computing whether compliance was achieved at each time step and how much oxygen was
required for achieving compliance. The calculation procedure mirrors the operational procedure that
Tillery will use for meeting compliance. The calculation procedure of the system aeration model includes
the following steps:
54

1. Flows at each time step were computed based on archival data. Zero project flows were replaced
by minimum flows of either 725 cfs (March 15th to May 15th) or 330 cfs at all other times.
The flows were separated into turbine flows and bypass flows. The bypass flows are either the
minimum flows through the crest gate or dam tainter gate spill flows.
3. If the influent DO is greater than 5.0 mg /L and the plant load is greater than zero, then no aeration
is applied and the tailrace DO is set to be the same as the influent DO.
4. If the influent DO is less than 5.0 mg /L and the plant load is greater than zero, then an iterative
procedure is employed to compute the DO added by the reservoir forebay oxygen diffuser system
and the DO added by turbine venting aeration:
a. The amount of DO turbine aeration provides is computed. If the tailrace DO with turbine
aeration meets 5.0 mg /L, then the tailrace DO is set to the DO value with turbine
aeration.
b. If the DO is less than the target, then the influent DO is increased with the reservoir
forebay diffusers. The influent DO is increased to the level at which the turbine aeration
can then meet the target exactly. This requires an iterative solution because the DO
uptake that the turbine aeration provides is dependent on the influent DO concentration.
c. If turbine aeration in conjunction with the maximum oxygen flow from the forebay
diffusers cannot meet the target, then a portion of the turbine flow is diverted to spill.
This would have been necessary for only one event in the archival data on August 30,
2005. In this case, the turbine flow exceeded 16,000 cfs. A spill flow of approximately
4,500 cfs would have been necessary to meet the minimum target of 4.0 mg /L.
5. If the influent DO is less than 5.0 mg /L and the plant load is zero, then a minimum flow solution
is assumed. The minimum flow is 725 cfs during spawning season and 330 cfs at all other times.
The DO is assumed to be 6.0 mg/L for minimum flows coming from reservoir surface water.
6.2 Model Data and Results
Five years of archival data were used to evaluate the operation of the Tillery aeration system to represent
a range of hydrologic conditions. These data are described above and were provided by Progress Energy.
Figure 6 -1 presents exceedance plots of the project flows for the five years modeled. The highest flow
years are 2005 and 2009; the lowest flow years are 2007 and 2008; and 2010 is an intermediate flow year.
The exceedance also shows that a significant portion of operation will occur at minimum flow conditions,
which are flows 725 cfs or lower. For example, for all years, minimum flows occur 60% of the time
during the oxygen compliance season. For the lower flow years, 2007 and 2008, minimum flows occur
over 70% of the time.
Figure 6 -2 presents typical input data to the model and the aeration results. This figure includes the
project flow rate, the water temperature, and three different DO levels: (1) the influent DO; (2) the DO
concentration of the water entering the turbines after reservoir forebay oxygenation is applied; and (3) the
DO concentration of the water leaving the powerhouse after turbine aeration is applied.
Figure 6 -3 presents an exceedance plot of the oxygen flow rates required by the reservoir forebay oxygen
diffuser system to meet a target DO of 5.0 mg /L. The oxygen flow rates have been filtered to exclude
values of zero; therefore, the data represent the portion of time that the diffuser system is operating. The
55

maximum capacity of 150 tons /day was needed in only 2 years, 2005 and 2007. In those years the
maximum capacity was needed less than 1% of the time. Therefore, the system is adequately sized to
meet the oxygen requirements for the target DO compliance levels.
Figure 6 -4 presents an hourly exceedance plot for the tailrace DO. This figure shows that a target of
5.0 mg /L is consistently met with the exception of August 30, 2005, when the DO falls to 4.1 mg /L. On
this date, high flows in excess of 16,000 cfs occurred while the influent DO was less than 1.0 mg /L. A
spill flow of 4,500 cfs is provided in this simulation which is required to achieve the hourly target of 4.0
mg /L.
Figure 6 -5 presents the daily averaged exceedance plot of tailrace DO. The daily average of 5.0 mg /L is
continually met for all years.
Figure 6 -6 presents the oxygen required from the reservoir forebay diffusers to meet the DO targets on a
monthly basis. August and July required the largest amounts, which varied from 240 to 960 tons.
Operation begins in May and extends through October. However, minimal oxygen is required for the
beginning and ending months. Figure 6 -7 presents the oxygen required for each year that was analyzed.
The largest amount, which was 1,880 tons, was required in 2005. The lowest, which was 750 tons, was
required in 2009.
6.3 Summary and Conclusions
A system aeration model was created to simulate the effects of operating the Tillery aeration system,
which includes an oxygen diffuser, turbine aeration, and bypass flows through a crest gate to meet
minimum flow requirements and through dam tainter gates to release higher infrequent spill flow rates.
Five years of archival data covering a range of hydrologic conditions (i.e., wet, dry and average flow
years) were used to create the input files to the model. These data and the model were used to simulate
the proposed operation of the Tillery aeration system. This includes minimum flow releases, using
turbine aeration as the first option for meeting the tailrace DO requirement, and using the reservoir
forebay oxygen diffuser system when the turbine aeration does not achieve the target DO compliance
level. Spill flows can also be used to achieve the target if turbine aeration combined with the maximum
oxygen flow from the diffusers does not meet the target.
This model shows that the oxygen diffuser system is capable of continually meeting the target DO water
quality standards. Both the instantaneous DO compliance target of 4.0 mg /L and the daily average
compliance target of 5.0 mg /L were continually met. The analyses show that the maximum oxygen flow
rate from the reservoir oxygen diffuser system is required for only two years of operation and for less than
one percent of the operating time. Therefore, the oxygen diffuser capacity of 150 tons /day is appropriate
for meeting DO requirements at the Tillery Development. The amount of oxygen that is required varies
annually and ranges from 750 tons in 2009 to 1,880 tons in 2005.
M:

Figure 6 -1. Project Flow Exceedance Plot for Tillery
Figure 6 -2. Typical Input Data and Results for the System Aeration Model
57
Influent DO —DO Entering Turbines —Tailrace DO —
Project Flow
12
24,000
10
- -
- - -' - - - - - - - - - - - - - - - - - ----- - - - - -- - - - -- - - -
-- - - - - -' - -
- - -
20,000
8
- -
- - - - - - - - - - - - - - -- --- - - - - -- - -- - - - - - - -
-- - - - -- -
- --
16,000
+
6
-- - -- - -- --
-
-
12,000
O
O
4 ---
7--
T - - - - - r
8,000
2
- -
- - -' -- - -' -- -------------------- - - - - -' -
- - - - -'- -
--
4,000
0
0
08/10/05 08/11/05 08/11/05 08/12/05 08/12/05 08/13/05 08/13/05
08/14/05 08/14/05
08/15/05
08/10/05
Figure 6 -2. Typical Input Data and Results for the System Aeration Model
57

160 -2005 -2007 -2008 -2009 -2010
140 -- -- - - - - - - ----- r----- r - - - - - r - - - - - r ----- - - - - - - - - - - - - - - - - -
Q 120 - - - - -- -----,-----,----------r-----r----------------
U)
C
H 100 F
O 60 - --
IL
40 -----,------,-----,-----,----------r-----r----------------
X
0
20 ---------- - - - - -- - - - -- -------------------------------
0
0 2 4 6 8 10 12 14 16 18 20
Exceedance ( %)
Figure 6 -3. Exceedance Plot of Diffuser Oxygen Flow Rate
Figure 6 -4. Hourly Exceedance Plot of the Predicted Project Discharge DO
58

Figure 6 -5. Daily Average Exceedance Plot of the Predicted Project Discharge DO
1,200
■ 2005 ■ 2007 2008 ❑ 2009 ■ 2010
1,000
800
C
N
A
K
0 600
O
N
C
H 400
200
0
May Jun Jul Aug Sep Oct
Figure 6 -6. Monthly Oxygen Requirements for the Diffuser
59

2000
1800
1600
1400
C
1200
A
O 1000
O
800
C
O
~ 600
400
200
0
2005 2007 2008 2009 2010
Figure 6 -7. Annual Oxygen Requirements for the Diffuser
•1

7.0 EVALUATION OF LOCATION OF THE COMPLIANCE MONITOR
Because of the width and complexity of the braided channel in the Tillery tailrace, significant lateral
variations in the tailrace DO occur. To evaluate the lateral variation, two additional DO monitors were
deployed on the East and West sides of the channel, and at the same distance from the dam as the USGS
monitor. The assessment period was similar to the period of the crest gate evaluation in August 2011. It
should be noted here that the USGS data presented in the report are provisional data and subject to change
with final quality assurance review by the USGS.
Figures 7 -1 through 7 -3 present the results of the comparisons between these three monitor locations,
which include the following observations:
1. During generation, only minor differences occur in the DO measurements. Large generation
flows provide a fairly uniform flow with a uniform DO distribution at the compliance
measurement location. These differences may be caused by a variety of factors, which include:
the differing aeration characteristics of the units; differing flow combinations of units that are
operating to meet the generation requirement; and measurement tolerances of the instruments.
2. During periods of non - generation, the monitor on the west bank of the bridge typically records
the highest DO for two reasons: (1) the west channel receives leakage from the tainter gates on
the dam (aerated water leakage), and (2) more photosynthesis occurs during the morning on the
west bank because it receives longer periods of sunshine. The east bank DO is highly variable
and is typically lower than the west bank because it receives the low DO wicket gate leakage. In
addition, the east bank receives less sunshine with resulting lower oxygen production from
photosynthesis of aquatic plants. However, when the crest gate was operating, the east bank
monitor exhibited the highest DO during the nighttime hours since the flow path from the dam is
relatively unobstructed and water reaches the east bank faster, which limits DO removal
occurring from plant /algal aquatic respiration.
3. The center monitor (USGS site) represents a balance between the two bank extremes and
therefore is more indicative of the average tailrace DO levels. However, the center monitor also
provides the lowest DO levels when the crest gate is operating.
In summary, the lateral variations in the DO measurement are a result of interacting physical and
biological processes occurring in the tailrace. The amount of aquatic vegetation in the immediate tailrace
area greatly influences DO dynamics, especially during non - generation periods during nighttime hours.
The amount of aquatic plant biomass will vary from year to year depending upon prevailing
environmental factors and, thus, the subsequent influence on tailrace DO dynamics will also vary from
year to year. These 2011 data results, along with previous minimum flow tests conducted during the
2007 -2010 period, showed that crest gate operation meets minimum flow requirements; provides a
measurable DO increase at the compliance location; and meets the 4.0 mg /L instantaneous compliance
target level.
61

Figure 7 -1. Lateral Variation of Tailrace Dissolved Oxygen and Crest Gate Operation
Tillery Tailrace Dissolved Oxygen and Crest Gate Operation
—USGS DO —East Bank Sonde Center Sonde
—West Bank Sonde —Crest Gate Spill
18
1000
17
16
900
15
800
14
m
13
700
E
12
11
600
a
10
0
0
9
■I■
500
LL
v
8
6
■I■I�i�l
400
N
7
_
%�
5
300
4
200
■imi■
lwl
2
100
■I ■I
■I
■I
■�
■I
0
0
O�
O� O� O� O� O� O�
O.
^ry. O. ^ry. O. ^ry. O.
O \n�
\^n ^ \n� ^n nn ^^ \^n
^� ^�
0 \^
0 \^ \�^\ 0 \ \dry 0 \
0 0 0
2011
■I
■
■
■
■II
■I
I■
I
■'■i■I■
.
■
■
■
■I
■I
■ I■
■IWPM
.
I
I■
■
■
■I
■
I 1
�■
■
■
■
■�
■J
■
I
I
■I
■
■
■ I
.,,
:
=
1
" �
��
I■
�rI�
II
'���
���
„
■
r■I
!
�■
ism
loommon
.
. .
. . . . . . . . . . . . . .
. . .
Figure 7 -1. Lateral Variation of Tailrace Dissolved Oxygen and Crest Gate Operation
Figure 7 -2. Lateral Variation of Tailrace Dissolved Oxygen and Crest Gate Operation, 8/10-
8/13/2011
CL
Tillery Tailrace Dissolved Oxygen and Crest Gate Operation
—USGS DO —East Bank Sonde Center Sonde
—West Bank Sonde —Crest Gate Spill
18
1000
17
16
900
15
800
14
m
13
700
E
12
11
600
a
10
0
0
9
500
LL
v
8
6
400
N
7
_
%�
5
300
4
200
3
2
100
1
0
0
O�
O� O� O� O� O� O�
O.
^ry. O. ^ry. O. ^ry. O.
O \n�
\^n ^ \n� ^n nn ^^ \^n
^� ^�
0 \^
0 \^ \�^\ 0 \ \dry 0 \
0 0 0
2011
Figure 7 -2. Lateral Variation of Tailrace Dissolved Oxygen and Crest Gate Operation, 8/10-
8/13/2011
CL

Figure 7 -3. Lateral Variation of Tailrace Dissolved Oxygen and Crest Gate Operation,
8/15 - 8/18/2011
63
Tillery Tailrace Dissolved Oxygen and Crest Gate Operation
-USGS DO -East Bank Sonde - Center Sonde
-West Bank Sonde -Crest Gate Spill
12
1000
11
900
10
800
9
m
8
700
E
7
600
w
6
500
0
0
'O
LL
5
400
N
0
N
N
4
300
3
2
200
1
100
0
0
.00
00 .00 00 .00 00
.00
0 0 0
2011
Figure 7 -3. Lateral Variation of Tailrace Dissolved Oxygen and Crest Gate Operation,
8/15 - 8/18/2011
63

8.0 SUMMARY AND CONCLUSIONS
This report describes testing and modeling that were performed to evaluate the capability of the Tillery
Hydroelectric Plant for achieving a tailrace DO compliance of 4.0 mg /L and 5.0 mg /L for daily average
values based on 15- minute interval readings. A summary of the test and model results include the
following:
1. Unit air flow rates and the resulting DO uptake with turbine venting were measured for Units 1
through 4. The maximum DO uptake for Units 1 through 3 ranged from approximately 0.6 to 1.4
mg /L. Unit 4 achieved a significantly higher DO uptake of 2.7 mg/L, but only at low power
settings less than 10 MW. These results were similar to previous turbine aeration tests conducted
from 2007 to 2010.
Tests with the reservoir oxygen diffuser system demonstrated that it provides the increase in DO
necessary to meet performance goals during power generation as measured at the tailrace DO
compliance point located at the NC Highway 731 Bridge. On the first day of the test, with no
oxygen flow from the diffuser and with turbine venting turned off, turbine flows produced a DO
that fell below 3.0 mg /L. By the third day of testing, with sustained operation of the diffuser, the
DO at the compliance point was consistently 5.0 mg /L or higher. On the subsequent days of
testing, the DO periodically exceeded 6.0 mg /L.
3. A turbine aeration model was created and calibrated with data from turbine aeration tests to
predict both the amount of unit air flow that each unit can draw into it and the corresponding DO
uptake for that airflow.
A system aeration model was created to evaluate the combined effects of turbine aeration, oxygen
diffusers, and minimum flow releases through the crest gate and higher flow releases through the
spill gate. The model predicted that both the minimum target of 4.0 mg /L and the daily average
target of 5.0 mg /L can be met in the discharge at the powerhouse. The model does not include
the nighttime respiration of aquatic plants, which can have significant effects on achieving the
DO compliance during minimum flow periods. However, field data collected in August 2011,
and previous years, showed that targets for both the average daily DO and the minimum DO were
attained with crest gate operation.
Testing was performed to evaluate the effectiveness of crest gate flows for achieving the target
DO at the compliance location. During minimum flow periods, respiration by aquatic plants has
a substantial impact on DO in the early morning hours. On evenings when the crest gate flow
was not operated, the DO ranged between 2.0 and 3.0 mg /L. When the crest gate was opened,
soon after generation stopped, the minimum DO of 4.0 mg /L was generally achieved. Slight
excursions below 4.0 mg /L were observed when crest gate operation was delayed by more than
two hours after generation stopped.
64

6. However, as specified in the Project 401 Water Quality Certificate (NCDWQ 2008), it should be
noted that the 330 cfs minimum flow tested under these verification trials will not be required
until after the final and non - appealable FERC license has been issued for the Yadkin -Pee Dee
Hydroelectric Project as well as for the upstream Yadkin Hydroelectric Project No. 2197. The
Yadkin Project flows are necessary to meet the minimum flows at the Yadkin -Pee Dee Project.
Under the existing minimum flow conditions of 40 cfs required in the current Yadkin -Pee Dee
Project license, the North Carolina water quality standards are not being met during the nighttime
hours when there is no power plant generation and aquatic plant respiration demands decrease
DO concentrations in the Project tailwaters.
7. A comparison of three lateral DO measurements at the NC Highway 731 Bridge showed
appreciable variation between them. Because the water flows more directly to the east bank
under minimum flow conditions, the DO will be higher on this side of the tailrace due to the
shorter residence time and the reduced impact of the respiration effects of aquatic plants. For the
tests performed in this study, the DO measured near the east bank consistently exceeded the
hourly minimum of 4.0 mg /L when the crest gate provided the minimum flow.
65

9.0 REFERENCES
American Society of Mechanic Engineers, Fluid Meters Sixth Edition, New York, 1971
ARCADIS. 2010a. Yadkin -Pee Dee River Hydroelectric Project. FERC Project No. 2206. Dissolved
Oxygen Enhancement Methods for the Tillery and Blewett Falls Hydroelectric Developments. Phase IV
- 2009: Baffle Plates, Aeration Ring, Partial Trashrack Blockage and Air Diffuser Deployment.
Syracuse, NY. January 2010.
2010b. Yadkin -Pee Dee River Hydroelectric Project. FERC Project No. 2206. Dissolved
Oxygen Enhancement Field Verification Methods for the Tillery and Blewett Falls Hydroelectric
Developments. Phase IV - 2010 Draft Tube Venting, Minimum Flow Tests, and Engineering
Evaluations. Syracuse, NY. December 2010.
2010c. Progress Energy. Tillery Dissolved Oxygen Enhancement Program. Feasibility
Review. March 15, 2010. Syracuse, NY. March 15, 2010.
. 2010d. Progress Energy. Yadkin -Pee Dee Hydroelectric Project, Tillery Hydroelectric Plant.
Flexible Curtain Weir Concept to Increase Tailwater Dissolved Oxygen Concentration. Engineering
Report. Syracuse, NY. June 2010.
DTA (Devine Tarbell & Associates). 2007. Yadkin -Pee Dee River Hydroelectric Project. FERC Project
No. 2206. Investigation of Measures to Enhance Dissolved Oxygen Concentrations in the Tailwaters of
the Tillery and Blewett Falls Hydroelectric Developments. PHASE L Turbine Venting. April 2007.
2008. Yadkin -Pee Dee River Hydroelectric Project. FERC Project No. 2206. Investigation of
Measures to Enhance Dissolved Oxygen Concentrations in the Tailwaters of the Tillery and Blewett Falls
Hydroelectric Developments. PHASE IL Surface Mixing and Compressed Air. June 2008.
HDR -DTA. 2009. Yadkin -Pee Dee River Hydroelectric Project. FERC Project No. 2206. Investigation
of Measures to Enhance Dissolved Oxygen Concentrations in the Tailwaters of the Tillery and Blewett
Falls Hydroelectric Developments. PHASE III: 2008 Reservoir Air Diffuser with Surface Mixing. HDR-
DTA. June 2009.
McGinnis, D. F., A. Lorke, A. Wuest, A. St6ckli, and J. C. Little. 2004. Interaction between a bubble
plume and the near field in a stratified lake, Water Resources Research, 40, W10206,
doi:10.1029/2004WR00303 8.
Mobley, M. H., P. J. Wolff, and R. J. Ruane. 2010. Evaluation of Oxygen Diffuser System Requirements
for Tillery Hydroelectric Plant (FERC Project No. 2206). Mobley Engineering, Inc., Norris, TN.
September 2010.
NCDENR (North Carolina Department of Environment and Natural Resources). 2010. NC 2010
Integrated Report 5- 303(d) List, EPA Approved August 31, 2010. NCDENR Division of Water Quality,
Raleigh, NC.
NCDWQ (North Carolina Division of Water Quality). 2008. Yadkin -Pee Dee River Hydroelectric
Project for Tillery and Blewett Falls Reservoirs. Rockingham, Stanly, Anson, Richmond and
Montgomery Counties. DWQ 02010437, Version 02. Federal Energy Regulatory Commission Project
Number 2206. APPROVAL of 401 Water Quality Certification Modified. North Carolina 401 Water
Quality Certification. Pages 11 -12. September 30, 2008.
.:

Progress Energy. 2005a. Yadkin -Pee Dee River Project, FERC No. 2206. Intensive temperature and
dissolved oxygen study of the Pee Dee River below the Tillery and Blewett Falls Hydroelectric Plants.
Water Resources Group. Issues Nos. 7 and 8 - Lake Tillery and Blewett Falls Lakes and Tailwaters
Water Quality. November 2005.
.2005b. Yadkin -Pee Dee River Project, FERC No. 2206. Continuous water quality monitoring
in the Pee Dee River below the Tillery and Blewett Falls Hydroelectric Plants. Water Resources Group.
Issues Nos. 7 and 8 - Lake Tillery and Blewett Falls Lakes and Tailwaters Water Quality. November
2005.
2006a. Yadkin -Pee Dee River Project, FERC No. 2206. Monthly water quality monitoring
study of Lake Tillery, Blewett Falls Lake, and associated tailwaters. Water Resources Group. Issues
Nos. 7 and 8 - Lake Tillery and Blewett Falls Lakes and Tailwaters Water Quality. April 2006.
2006b. Application for license. Yadkin -Pee Dee River Project, FERC No. 2206. Submitted
by Progress Energy, Raleigh, North Carolina.
2006c. Yadkin -Pee Dee River Hydroelectric Project, FERC No. 2206. Continuous water
quality monitoring in the Pee Dee River below the Tillery and Blewett Falls Hydroelectric Plants, May -
October 2005.
2007. Application for Water Quality Certification pursuant to Section 401(a)(1) of the Clean
Water Act. Yadkin -Pee Dee River Hydroelectric Project, FERC Project No. 2206. Submitted by
Progress Energy, Raleigh, North Carolina. May 2007.
2010. Yadkin -Pee Dee River Hydroelectric Project, FERC No. 2206. Continuous water
quality monitoring in the Pee Dee River below the Tillery and Blewett Falls Hydroelectric Plants, May -
October, 2006 -2009. December 2010.
2011. Yadkin -Pee Dee River Hydroelectric Project, FERC No. 2206. Continuous water
quality monitoring in the Pee Dee River below the Tillery and Blewett Falls Hydroelectric Plants, May -
October 2010. December 2011.
Ruane, R. J., and D. F. McGinnis. 2007. "Applications of the Discrete - Bubble Model for Turbine
Aeration Systems," Waterpower XV Technical Papers CD -Rom, HCI Publications, Kansas City, MO.
Wuest, A., N. H. Brooks, and D. M. Imboden. 1992. Bubble plume modeling for lake restoration. Water
Resources Research, 28(12): 3235 -3250.
67

Progress Energy Carolinas, Inc.
Yadkin Pee -Dee Hydroelectric Project No. 2206
Tillery and Blewett Falls Developments
Dissolved Oxygen Compliance Implementation Plan
0 Progress Energy
January 20, 2012

Table of Contents
Section Page No.
Listof Tables .............................................................................................. ............................... iii
Listof Figures ............................................................................................. ............................... iii
1.0 Introduction ............................................................................................ ............................... 1
2.0 Project Description ................................................................................. ............................... 2
3.0 Background of Dissolved Oxygen Issues at the Project ......................... ............................... 3
3.1 Pee Dee River Water Quality Classification ..................................... ............................... 4
3.2 Continuous Water Quality Monitoring Program ............................. ............................... 4
4.0 DO Enhancement Technology Testing ................................................... ............................... 6
4.1 Tillery Development ......................................................................... ............................... 7
4.2 Blewett Falls Development ............................................................ ............................... 10
5.0 Implemented DO Enhancement Technologies .................................... ............................... 11
5.1 Tillery Development ....................................................................... ............................... 11
5.2 Blewett Falls Development ............................................................ ............................... 14
6.0 North Carolina Dissolved Oxygen Water Quality Standards ................ ............................... 16
7.0 Water Quality Compliance Monitoring Stations .................................. ............................... 17
7.1 Compliance Monitoring Station Locations ..................................... ............................... 17
7.2 Compliance Monitoring Equipment ............................................... ............................... 20
8.0 Compliance Monitoring and Reporting ................................................ ............................... 22
9.0 References ............................................................................................ ............................... 23
APPENDICES
Appendix A Yadkin -Pee Dee Hydroelectric Project No. 2206 Tillery and Blewett Falls
Developments Water Quality Certificate
Appendix B Letter to Mr. John Dorney, N.C. Division of Water Quality from Mr. Ken Kennedy,
Progress Energy, Hydro Operations, January 25, 2011

LIST OF TABLES
Table Page
1 YSI 600 OMS sensor specifications ................................................... ............................... 20
LIST OF FIGURES
Figure Page
1 Yadkin -Pee Dee River Basin showing location of the Yadkin -Pee Dee
Hydroelectric Project No. 2206 ......................................................... ............................... 3
2 Schematic of a reservoir oxygen diffuser system operation ............ ............................... 11
3 Map showing layout of the Tillery Hydroelectric Plant reservoir oxygen
diffusersystem .................................................................................. ............................... 12
4 Tillery Hydroelectric Plant turbine operations and tailrace DO measurements
on August 11, 2011 verification trials ............................................... ............................... 13
5 Longitudinal DO and temperature contours in the Lake Tillery intake
forebay area, August 11, 2011 .......................................................... ............................... 14
6 Draft tube venting system installed on Unit 3 of the Blewett Falls
HydroelectricPlant ........................................................................... ............................... 15
7 Dissolved oxygen levels recorded at the USGS water quality compliance
monitoring station located in the Blewett Falls tailrace, July- November, 2011 ............. 16
8 Location of USGS water quality compliance monitoring station at the N.C.
Highway 731 Bridge below the Tillery Hydroelectric Plant .............. ............................... 19
9 Location of USGS water quality compliance monitoring station in the tailrace
below the Blewett Falls Hydroelectric Plant ..................................... ............................... 19

1.0 Introduction
Progress Energy Carolinas, Inc. (Progress Energy) is currently relicensing the Yadkin -Pee Dee
Hydroelectric Project (FERC Project No. 2206) with the Federal Energy Regulatory Commission.
Progress Energy filed its license application with FERC on April 26, 2006 and entered into a
Comprehensive Settlement Agreement (CSA) signed by 12 stakeholders on June 29, 2007
(Progress Energy 2006a, 2007a). The CSA was filed with FERC on July 30, 2007 as part of the
relicensing record. Section 2.3 of the CSA specifically addressed water quality issues, including
dissolved oxygen (DO). In April 2008, FERC issued the Final Environmental Impact Statement
for the Project (FERC 2008) which recommended that Progress Energy: (1) implement a DO plan
that would have DO meeting state water quality standards by the end of 2011; (2) determine
the final location for a water quality monitoring equipment near the N.C. Highway 731 Bridge,
where DO would be continuously monitored; and (3) install equipment, and monitor water
temperature and DO immediately downstream of the Blewett Falls tailrace.
As part of the relicensing process, Progress Energy applied for a 401 Water Quality Certificate
(WQC) with the N.C. Division of Water Quality on May 17, 2007 (Progress Energy 2007b). The
401 Water Quality Certificate application specified a DO Enhancement Plan to address
seasonally low DO conditions observed in each power plant tailwaters. The Plan provided a
schedule for Progress Energy to meet the North Carolina DO water quality standards. During
February 2008, the North Carolina Division of Water Quality (NC DWQ) issued the 401 Water
Quality Certificate (WQC) for the Yadkin -Pee Dee Project, which was subsequently modified and
reissued on September 12, 2008. In the issued 401 WQC, the NC DWQ outlined conditions for
meeting the DO water quality standards at the Project (NC DWQ 2008a; Appendix A). The 401
WQC stated that Progress Energy must have measures in place at the Tillery and Blewett Falls
Developments by the end of December 2011 that will enhance dissolved oxygen levels and
meet state water quality standards in the Pee Dee River below each hydroelectric
development.
The DO Enhancement Plan outlined a systematic, step -wise technological evaluation program
to determine the most cost - effective technology at each power plant that would meet the
North Carolina DO Water Quality Standards (4 mg /L instantaneous and 5 mg /L daily average) by
the end of 2011 (Progress Energy 2007b). As part of the DO Enhancement Plan, Progress
Energy committed to filing a DO Implementation Compliance Plan with the FERC and NC DWQ
which specifies the operational technologies employed to meet the DO water quality standards
and the compliance monitoring measures.
Fll

As specified in the Project 401 Water Quality Certificate (NCDWQ 2008a), the 330 cfs minimum
flow tested under the DO verification trials and all other conditions of the 401 WQC will not be
required until after the final and non - appealable FERC license has been issued for the Yadkin -
Pee Dee Hydroelectric Project, as well as for the upstream Yadkin Hydroelectric Project No.
2197. The Yadkin Project flows are necessary to meet the minimum flows at the Yadkin -Pee
Dee Project. Under the existing minimum flow conditions of 40 cfs required in the current
Yadkin -Pee Dee Project license, the North Carolina water quality standards are not being met
during the nighttime hours when there is no power plant generation and aquatic plant
respiration demands decrease DO concentrations in the Project tailwaters. Furthermore, under
the existing minimum flow conditions without the implemented DO enhancement measures,
the DO water quality standards are met during the day time hours with increasing DO levels
caused by aquatic plant photosynthesis until power plant generation decreases DO levels.
Aquatic plant photosynthesis and respiration effects are most evident during the growing
season months.
The purpose of this report is to specify the technological and operational measures that
Progress Energy will undertake to comply with the North Carolina DO Water Quality Standards.
This report also contains the compliance monitoring and reporting measures as outlined in 401
WQC issued by the NC DWQ. Filing of this DO Enhancement Plan fulfils the schedule set forth
by Progress Energy in its 401 WQC application and specified in the 401 WQC issued by the NC
DWQ on September 12, 2008.
2.0 Project Description
Progress Energy's Yadkin -Pee Dee River Project (Project) is located on the Yadkin -Pee Dee River
in the State of North Carolina (Figure 1) and consists of the upstream 84 megawatt (MW) Tillery
Development and the downstream 24.6 MW Blewett Falls Development. Each development
consists of a dam, powerhouse, impoundment, substation, structures used in connection with
the Project, water rights, rights -of -way, lands, and interest in lands necessary for the operation
and maintenance of the Project. The Blewett Falls and Tillery developments were constructed
in the early 1900s. Blewett Falls was placed in operation in 1912, and the Tillery Development
commenced operations in 1928. The primary purpose of the Project is to generate electricity
and meet other important electrical system needs for the benefit of Progress Energy's
ratepayers. The Project is used for critical load- following and on -peak generation and its
economic viability is dependent on serving these specific purposes. Both Tillery and Blewett
Falls also have the capability to "black start ", meaning the ability to come online under system
blackout conditions to support local loads and aid in overall control area restart and recovery.
4

The Project has provided valuable service as a peaking and load- following electrical generation
resource throughout its entire history.
3.0 Background of Dissolved Oxygen Issues at the Project
Progress Energy has conducted water quality - related evaluations at the Tillery and Blewett Falls
Developments since 2004 as part of the FERC relicensing process and NC DWQ 401 Water
Quality Certification process for the Yadkin -Pee Dee River Hydroelectric Project (FERC No.
2206), which includes both developments (Progress Energy 2005a, 2005b, 2006a, 2006b, 2006c,
2010, 2011). These evaluations have been conducted to address temporal and spatial variations
in seasonally low dissolved oxygen concentration (DO) levels in certain portions of the Pee Dee
River in the vicinity of each development.
Figure 1. Yadkin -Pee Dee River showing location of the Yadkin -Pee Dee Hydroelectric
Project No. 2206 (Tillery and Blewett Falls Developments).
41

3.1 Pee Dee River Water Classification
A 5 -mile reach of the Pee Dee River below the Tillery Development (i.e., 4.9 river miles from
Norwood Dam to Rocky River) has been listed as impaired for aquatic life due to low DO and
low pH under Section 303(d) of the Clean Water Act by the North Carolina Department of
Environment and Natural Resources - Division of Water Quality (NCDENR 2010). The Pee Dee
River below the Blewett Falls Development was not listed as impaired for DO on the NC DWQ
2010 303(d) listing.
The sections of the Pee Dee River from Tillery Dam to Blewett Falls Lake are classified by the
NCDWQ as Class WS -IV,B, WS -V,B and WS- IV,B &CA waters, which are suitable for the
designated uses of aquatic life use and propagation, drinking water and primary and secondary
recreational uses. From Blewett Falls Lake to Hitchcock Creek, the Pee Dee River is classified as
a Class C river (NCDWQ 2011). The designated uses of Class C waters are propagation of aquatic
life and secondary recreational uses.
Downstream of the Tillery Development, Progress Energy and the NCDWQ have documented,
on occasion, the occurrence of DO concentrations below the state water quality standards of 4
mg /L measured on an instantaneous basis and 5 mg /L measured on a daily average basis (NC
DWQ 2007, 2008b). These occurrences appear to coincide with summertime seasonal periods
of reservoir thermal stratification, with resulting low DO conditions in hypolimnetic waters (i.e.,
the bottom and most dense layer in a thermally stratified water body).
For the Blewett Falls Development, DO concentrations in the tailwater area have been recorded
on occasion to be below state water quality standards. Similar to the Tillery Development,
these low DO occurrences coincide with periods of seasonal reservoir thermal stratification
with their attendant low DO conditions in the reservoir bottom waters, especially during the
summer period from May through September.
In addition, aquatic plant photosynthesis and respiration dynamics in both power plant
tailwaters affect the DO regime in these areas. Creek inflow of low DO water may also
influence DO dynamics in these tailwater areas on occasion.
3.2 Continuous Water Quality Monitoring Program
Progress Energy conducted an extensive program of continuous water quality monitoring
program in the Pee Dee River below each of the Project developments from 2004 to 2010
(Progress Energy 2005a, 2005b, 2006b, 2006c, 2010, 2011). The monitoring program was
C!

developed and implemented in consultation with the NCDWQ as part of the relicensing studies
for the Project (Progress Energy 2004). In addition to DO concentration levels, the monitoring
program also recorded water temperature, pH, and conductivity. This continuous monitoring
program showed several consistent spatial and temporal trends during the 2004 -2010 period as
follows:
• This monitoring program assessed the spatial and temporal patterns of temperature and DO
concentrations in the Pee Dee River downstream of the Tillery and Blewett Falls hydroelectric
plants using in -situ continuous monitoring instruments during May through October, 2005-
2011. Water temperature and DO concentrations were measured with YSI 600 XLM continuous
water quality monitoring sondes which obtained measurements every 15 minutes during the
monitoring period.
• DO concentrations in both power plants tailwaters were below one or both state water
quality DO standards generally between mid May and September, with the lowest DO
concentrations occurring in late July and August during the period of greatest thermal
stratification in each project reservoir.
• Dissolved oxygen concentrations in the river generally increased with increased distance from
the Tillery Plant due to re- aeration in the river channel and tributary inflow.
• Dissolved oxygen concentrations did not consistently increase throughout river tailwaters
with increased distance from the Blewett Falls Hydroelectric Plant. Both North Carolina water
quality standards were met more often at the lowermost monitoring station, located below the
confluence with Hitchcock Creek, approximately 7 miles downstream of the power plant.
• Spatial trends in DO concentrations in the two river reaches below the power plants were
similar during all monitored years.
• Dissolved oxygen concentrations were affected by natural diurnal cycles of aquatic plant
photosynthesis and respiration as well as power plant operations. Dissolved oxygen
concentrations usually increased during daylight hours and decreased at night as a result of
aquatic plant photosynthesis and respiration.
• The length of the period that DO concentrations did not meet the water quality standards
was affected by inter - annual climatological differences, reservoir stratification patterns,
reservoir inflows, degree of aquatic plant photosynthesis and respiration, and frequency of
plant generation. Reservoir destratification and DO levels above the state water quality
0

standards usually occurred by early to late September to mid October during the 7 -year
monitoring period. Dissolved oxygen values were above the North Carolina DO water quality
standards by the end of October for this same 7 -year monitoring period.
4.0 DO Enhancement Technology Testing
A DO enhancement technological evaluation program was conducted at the Tillery and Blewett
Falls developments during the 2006 -2010 period. This program was designed to systematically
evaluate various DO enhancement technologies through the conduct of field testing of the
currently available, feasible technologies. This program identified the most technologically
feasible methods for meeting the state DO water quality standards. Each of the evaluated
technologies was assessed for DO uptake efficiency, impacts to turbine - generator performance,
and unit operation and maintenance impacts.
The following DO enhancement technologies were evaluated at the Tillery and Blewett Falls
developments from 2006 to 2011:
• Turbine Aeration with Passive Air Admission (Tillery and Blewett Falls Plants) —The
vacuum breaker or draft tube vents were used for the air admission during field tests.
Initially the Tillery Plant tests were performed without baffle plates and then baffle
plates were installed in the draft tubes to increase the passive air flow (DTA 2007, 2008;
ARCADIS 2010a, 2010b).
• Turbine Aeration with Forced Air Injection (Tillery Plant) —The air inlet locations for
the forced air field tests included the vacuum breaker, draft tube vents, and through a
nose cone ring that was fabricated for these tests and installed at the top of the draft
tube (DTA 2008; HDR -DTA 2009; ARCADIS 2010a, 2010b). An air compressor delivered
the forced air injection. A desktop engineering feasibility study also evaluated the
potential of high volume air blowers in providing turbine aeration (ARCADIS 2010c).
• Selective Surface Water Withdrawal (Tillery Plant) —These field tests involved
blocking off the lower section of the trashrack of Unit 1 with canvas tarps (ARCADIS
2010a). Tests were performed with the lower 20 and the lower 40 feet of the trashrack
blocked off. A follow -up feasibility modeling study was conducted evaluating a flexible
curtain weir that would be located in the intake forebay area (ARCADIS 2010d).
• Surface Water Mixing (Tillery and Blewett Falls Plants) —These field tests included
testing an array of four smaller impellers and testing a single large impeller mounted on
a pontoon boat platform (DTA 2008; HDR -DTA 2009).
1.1

• Compressed Air Bubble Diffusers (Tillery and Blewett Falls Plants) –These field tests
involved placing two diffuser racks in front of the turbine intake trash racks. During unit
operation, compressed air was provided to the diffusers to aerate the water flowing into
the turbine (Tillery and Blewett Falls plants) (DTA 2008; ARCADIS 2010a). A test was
also performed with a diffuser installed in the Blewett Falls tailrace (HDR -DTA 2009).
• Surface Water Mixers Operating in Combination with Draft Tube Vent Passive Air
Admission (Tillery and Blewett Falls Plants)— Various field test combinations of surface
water mixing and passive air admission with turbine venting at different unit generation
settings (DTA 2008; HDR -DTA 2009).
• Compressed Air Bubble Diffusers at the Intake Structure in Combination with Draft
Tube Passive Air Admission (Tillery Plant)— Various field tests of both technologies
operated in tandem at different unit generation settings (DTA 2008; HDR -DTA 2009;
ARCADIS 2010a).
• Reservoir Oxygen Diffuser System (Tillery Plant) —A desktop engineering feasibility
study for the Tillery Plant was conducted during 2010 using historical plant operating
and environmental data (Mobley et al. 2010, 2011). A reservoir oxygen diffuser system
was installed in front of the intake forebay of Lake Tillery and successfully tested during
July and August 2011 (Ruane et al. 2011).
In addition, the proposed minimum flows for the new license term were tested at each
hydroelectric plant to determine if those flows would meet the DO water quality standards
(DTA 2008; HDR -DTA 2009; ARCADIS 2010a, 2010b; Ruane et al. 2011). At the Tillery Plant, the
minimum flow trials were conducted for 24 -hour periods with an approximate 330 cfs surface
release from the dam crest gate sluiceway. The minimum flow trials at the Blewett Falls Plant
were conducted for 24 -hour periods with an approximate 1200 cfs release from a selected
generating unit.
Conclusions from the DO verification trials at both power plants are summarized below.
4.1 Tillery Development
Reservoir Oxygen Diffuser System
• To achieve compliance with the state DO water quality standards with power plant
operations, a reservoir oxygen diffuser system was installed during 2011 and operated in
conjunction with passive venting on Units 1, 2, and 3 (Ruane et al. 2011). A feasibility study
II

conducted by Mobley et al. (2010) recommended a diffuser system maximum capacity of 150
tons per day with system operation to match hydro generation releases.
• Tests with the reservoir oxygen diffuser system demonstrated that it can provide the
increase in DO necessary during power plant generation to meet DO water quality standard
requirements as measured at the tailrace compliance point located at the N.C. Highway 731
Bridge (Ruane et al. 2011). On the first day of the test with no oxygen flow from the diffuser
and with turbine venting turned off, turbine flows produced a DO that fell below 3.0 mg /L. By
the third day of testing with sustained operation of the diffuser, the DO at the compliance point
was consistently 5.0 mg /L or higher. On the subsequent days of testing the diffuser system, the
DO periodically exceeded 6.0 mg /L.
• A system aeration model predicted that both the minimum target of 4.0 mg /L and the daily
average target of 5.0 mg /L can be met in the discharge at the powerhouse.
Draft Tube Venti
• The DO uptake for turbine aeration of Units 1 to 3 during the 2011 verification trials was
measured and ranged from approximately 0.6 to 1.4 mg /L. Units 1 and 3 provided greater DO
gains than Unit 2. Unit 4 achieved a significantly higher DO uptake of 2.7 mg /L, but only at low
power settings less than 10 MW. These results were similar to previous turbine aeration tests
conducted from 2007 to 2010.
• Passive aeration with draft tube venting will not solely achieve the required DO compliance
levels under all conditions.
• For Units 1, 2 and 3, the addition of baffle plates or the modification to the baffle plate
design improved the magnitude of the air flow through the 6 inch vacuum breakers. However,
the improved air flow did not provide any consistent and measurable increases in DO uptake
when compared to the 2009 results without use of the baffle plates.
• The baffle plate design utilized on Unit 1 provides approximately 10% greater air flow than
the design used on Unit 3. Units 1 and 3 both achieve air flow at all tailwater elevations, with
Unit 1 peaking at about 35 cfs at the lowest tailwater elevation, and Unit 3 peaking at about 30
cfs. The best air flow appears to be achieved near the most efficient power output (i.e., at
"economy load ") for both units. Unit 1 generally exhibits air flow at all power outputs, while
Unit 3 does not aerate below about 15 MW.
• The 10 -inch draft tube vents on Units 1 -3 did not create air flow through these vents, either
with or without baffle plates, to be an effective venting option.
E:3

• For single unit operation, Unit 2 provided the greatest DO uptake at the proposed DO
compliance monitoring location. The maximum DO measurement occurred with Unit 2 at
minimum load.
• For two unit operation, Unit 1 at best efficiency and Unit 4 at 9 to 10 MW load with the
vacuum breaker open provided the greatest DO uptake at the compliance monitoring location.
However, the vacuum breaker vent on Unit 4 only provides aeration up to a 9 to 10 MW load
and closes automatically at higher generation loads.
• DO levels with three and four units operating are less than DO levels with one or two units
operating in a venting mode.
• When operating Units 1, 2 and 3, the addition of Unit 4 with the vacuum breaker open (9 -10
MW load) does not increase the DO at the compliance monitoring location. This test result was
likely related to flow patterns where the Unit 4 generation flow is directed towards the west
river bank shoreline with the other units operating.
Minimum Flow and Compliance Monitoring
• Using the crest gate to provide minimum flows of 330 cfs is effective for achieving the target
DO of 4.0 mg /L at the compliance location. During non - generation periods in the early morning
hours, the DO dropped to 2.0 to 3.0 mg /L when the crest gate was not operated. When crest
gate flows were started within two hours after generation stopped, the target DO of 4.0 mg /L
was achieved.
• As specified in the Project 401 Water Quality Certificate (NCDWQ 2008a), the 330 cfs
minimum flow tested under these verification trials and all of the other conditions of the 401
WQC will not be required until after the final and non - appealable FERC license has been issued
for the Yadkin -Pee Dee Hydroelectric Project, as well as for the upstream Yadkin Hydroelectric
Project No. 2197. The Yadkin Project flows are necessary to meet the minimum flows at the
Yadkin -Pee Dee Project. Under the existing minimum flow conditions of 40 cfs required in the
current Yadkin -Pee Dee Project license, the North Carolina water quality standards are not
being met during the nighttime hours when there is no power plant generation and aquatic
plant respiration demands decrease DO concentrations in the Project tailwaters. Furthermore,
under the existing minimum flow conditions without the implemented DO enhancement
measures, the DO water quality standards are met during the day time hours with increasing
DO levels caused by aquatic plant photosynthesis until power plant generation decreases DO
levels. Aquatic plant photosynthesis and respiration effects are most evident during the
growing season months.
01

• The selected DO compliance monitoring location (center of river at the Highway 731 Bridge)
provides a representative indication of DO concentrations for the majority of the operating
scenarios. However, during the 2011 trials, a comparison of three lateral DO measurements at
the N.C. Highway 731 Bridge (East Bank, Mid Channel, and West Bank) showed appreciable
variation between them. Because the water flows more directed to the East Bank under
minimum flow conditions, the DO will be higher on this side of the tailrace due to the shorter
residence time and the reduced impact of the respiration effects for aquatic plants. For the
tests performed in the 2011 study, the DO measured near the East Bank consistently exceeded
the hourly minimum of 4.0 mg /L when the crest gate provided the minimum flow.
4.2 Blewett Falls Development
• A draft tube vent system was designed and installed to meet the North Carolina water
quality standards during power plant generation period, including the expected minimum flows
during the next FERC license term.
• The new draft tube vent systems installed for Units 3 and 4 provide air flow in excess of
design conditions. A similar draft tube venting system was also installed on Units 1, 2, 5, and 6.
• During the 2010 minimum flow tests, both the instantaneous and daily average DO
compliance standards were met at the tailrace center buoy line monitoring location during
both the 24 -hour test with Unit 3 and the 24 -hour test with Unit 4.
• The maximum DO uptake achieved under various Units 3 and 4 operating scenarios in 2010
was 2.0 mg /L. This increase was accomplished with a minimum starting DO of 4.6 mg /L. This is
less than the target increase of 2.6 mg /L, which is projected for the worst case scenario.
• Testing of the complete draft tube venting system during the 2011 verification trials
demonstrated the system was capable of meeting the North Carolina DO water quality
standards.
• The DO compliance monitoring location is located in the tailrace, approximately 800 feet
downstream of the power plant.
0111

5.0 Implemented DO Enhancement Technologies
Based on the results of the tested technologies, Progress Energy implemented a reservoir
oxygen diffuser system with supplemental draft tube venting (Units 1 -3) at the Tillery Plant and
draft tube venting at the Blewett Falls Plant to achieve the desired goal of meeting the North
Carolina DO water quality standards (ARCADIS 2010b; Mobley et al. 2010; Ruane et al. 2011).
Additionally, reservoir surface releases from the dam crest gate to provide minimum flows are
capable of meeting the DO standards at the Tillery Development during nongeneration periods
(ARCADIS 2010a, 2010b; Ruane et al. 2011) when minimum flows are provided by the upstream
Yadkin Project in accordance with the issuance of the new FERC license (see Section 1.0,
Introduction).
5.1 Tillery Development
Progress Energy constructed a reservoir oxygen diffuser system at the Tillery Development
during 2011 to improve dissolved oxygen levels in hydropower generation releases. This type
of system has been installed at 16 hydropower projects around the U.S. to meet dissolved
oxygen compliance requirements in the downstream hydro power releases (Mobley
Engineering, Inc. 2011). The diffuser system distributes oxygen in the reservoir just upstream of
the dam (Figure 2). The diffuser system consists of four 3,500 foot long diffuser lines upstream
of the intake forebay supplied with gaseous oxygen from a bulk liquid oxygen facility on the
east shoreline of Lake Tillery (Figure 3).
The bulk oxygen facility has two 15,000 gallon horizontal storage tanks for liquid oxygen; four
26 ft vertical tower vaporizers to convert liquid oxygen to gaseous oxygen; and an oxygen flow
control skid to regulate gaseous oxygen flow into the diffuser lines. Liquid oxygen is delivered
to the facility by tanker truck. A Programmable Logic Controls (PLC) system regulates the
amount of oxygen delivered by the diffuser system based on the oxygen deficit in the reservoir
water column and amount of flow with power generation.
Surla ce Water
. Wthd --f
Z.-
Figure 2. Schematic of a reservoir oxygen diffuser system operation.
11

The diffuser lines are positioned in the submerged riverbed in front of the intake forebay and
numbered 1 -4 from the east shoreline out, corresponding to the turbine unit designations (Figure
3). In order to provide flexibility in the vertical placement of oxygen in the reservoir, the diffusers
are installed at two elevations. Diffuser lines Nos. 1 and 4 are at elevation 224 ft (54 feet deep at
nominal 278 ft normal lake elevation). Diffusers lines Nos. 2 and 3 are at elevation 212 ft (66 feet
deep at nominal 278 ft normal lake elevation). Typically, one diffuser line will operate continuously
at a pre- determined "maintenance" flow to ensure oxygenated conditions in the reservoir forebay
with power plant generation startup. The additional lines will deliver oxygen after plant start -up
depending upon the amount of flow with power generation. These additional lines will shut -down
when the power plant ceases the generation event. The diffuser system can operate in an auto or
manual mode.
Lake Tillery Oxygen System
�.o
� 1
L a ky e y'
2
O 250 500 1.000 Feet
Mob/e
Figure 3. Map showing layout of the Tillery Hydroelectric Plant reservoir oxygen diffuser
system.
RI`)

The diffuser system was successfully tested during July and August ( Ruane et al. 2011). Results
indicated that the system successfully met the desired compliance target level of 5 mg /L under
varying generation load scenarios (see Figures 4 and 5 as one diffuser test example and the
resulting reservoir DO conditions with the diffuser operating).
The reservoir oxygen diffuser system was tested over a five -day period on August 8 -12, 2011 to
investigate the performance of the system over a wide range of unit generation operations (see
Ruane et al. 2011 for complete test results). On the first test day, with the diffuser off and with
no turbine venting, high generation flows produced DO concentrations at the compliance
monitoring point that were less than 3 mg /L. During subsequent testing with diffuser operation
and turbine venting on, the DO periodically exceeded 6.0 mg /L. Minimum flow tests with crest
gate releases were also performed, and DO at the compliance monitoring point exceeded 4
mg /L.
Previous verification trials during the 2006 to 2011 period also indicated that supplemental
draft tube venting from Units 1 -3 provided approximately 0.6 to 1.4 mg /L increase in DO
concentrations. These trials also indicated that a minimum flow release of 330 cfs met the
desired DO water quality standards during nongeneration periods.
Figure 4. Tillery Hydroelectric Plant turbine operations and tailrace DO measurements on August 11,
2011 verification trials (from Ruane et al. 2011).
13

0
W
Distance (ft)
Figure S. Longitudinal DO and temperature contours in the Lake Tillery intake forebay area, August
11, 2011 (from Ruane et al. 2011).
5.2 Blewett Falls Development
New draft tube vents were installed at the Blewett Falls Plant during March through November
2010 (Figure 6). The new vents were installed on the draft tubes as they exited underneath the
power plant with the vent air intakes extending above grade at the penstock elevation (Figure
6). Two 8 -inch vents constructed of Schedule 80 PVC piping were installed on one of the two
draft tubes for Units 1, 2, 5, and 6 while two 8 -inch vents constructed of Schedule 80 PVC piping
were installed on both draft tubes for Units 3 and 4.
Operation trials were successfully performed on the partially completed system in August 2010
(Units 3 and 4) and on the entire completed system during the May- November 2011 period.
The Blewett draft tube system has a Programmable Logic Controls (PLC) auto - venting
configuration which obtains a real time radio - telemetry signal from the DO sonde and transmits
that signal into the PLC for automatic opening and closing the draft tube vent valve controls
depending upon the DO levels during unit generation. This PLC auto - venting system can also be
manually operated by an operator in case of loss of radio - telemetry signal or other equipment
failure.
F01I

i
■ P
Air Intake
Valve Controls
R
Unit3 Penstock
Figure 6. Draft tube venting system installed on Unit 3 of the Blewett Falls Hydroelectric
Plant.
0167

The graph shown below (Figure 7) shows the DO levels with the Blewett draft tube venting
system operation during the July 13 through November 30, 2011 time period:
10
0
8
aA
E 7
a�
6
aA
x X>' 5
O
4
O 3
7-Mi
1
X
\ \ \ \ \ \ \ \ \ \ \ \ O O O O N N N N N
F ` N N W F- F- N W F- N N \ \ \ \ \ \ \ \ \
W O \ O V 4�h F` \ 4�h F` 00 C71 F` F` N N l0 F` N W
\ \ \ N \ \ \ \ N \ \ \ \ N l0 01 \ \ M W O
N N N O N N N N O N N N N \ \ \ N N \ \ \
O O O F` O O O O F` O O O O N N N O O N N N
O O O F` F` O O O
Week
Figure 7. Dissolved oxygen levels recorded at the USGS water quality compliance monitoring
station located in the Blewett Falls tailrace, July- November 2011.
There were three brief instances of DO deviations below the 4 mg /L instantaneous water
quality standard (August 22, September 5, and October 2) while all daily average DO values
were above the 5 mg /L during the trial operational period. The DO deviation on August 22
occurred during one 15 minute interval measurement at 2230 hours. The DO deviation on
September 7 was maybe the result of a lightning strike a few days earlier that affected
communications transmission from the DO sonde to the auto venting equipment in the power
plant. The DO fluctuations on October 2 occurred during a 30- minute period just after
midnight.
6.0 North Carolina Dissolved Oxygen Water Quality Standards
The 401 Water Quality Certificate issued by the NC DWQ on September 12, 2008 (NC DWQ
2008b; see Appendix A) specifies compliance with North Carolina water quality DO standards in
the Project tailwaters as follows:
RR

"Progress Energy shall meet dissolved oxygen standards by December 2011. The
implementation schedule includes completion of field testing of DO enhancement options by
December 2008 and completing successful implementation of the best suited DO enhancement
technology by December 2011."
The two DO water quality standards that have to be met for warm waters in North Carolina (NC
DWQ 2007) are: (1) a minimum instantaneous value of 4.0 mg /L and (2) a daily (24 -hour)
average value of 5 mg /L.
7.0 Water Quality Compliance Monitoring Stations
7.1 Compliance Monitoring Station Locations
The 401 Water Quality Certificate issued by the NC DWQ specifies compliance monitoring
measures to ensure DO water quality standards are met in the Project tailwaters:
Tillery Plant
"Progress Energy will provide continuous monitoring of water temperature and dissolved
oxygen. Temperature and DO monitoring will occur below the Tillery Plant with equipment
installed by the Applicant in accordance with protocols approved by NCDWQ. The final location
of DO monitoring near the Highway 731 Bridge will be determined based upon further testing of
DO enhancement technologies and resulting patterns of DO concentrations in the Tillery
tailwater."
Blewett Falls Plant
"Progress Energy will provide monitoring of water temperature and dissolved oxygen.
Temperature and DO monitoring will occur immediately below the end of the Blewett Falls
tailrace with equipment installed by the Applicant in accordance with protocols approved by
NCDWQ."
Progress Energy met with NC DWQ and U.S. Geological Survey (USGS) personnel on January 13,
2011, to discuss water quality compliance monitoring equipment and site placement at both
power plants. This meeting included a field site visit at both power plant tailwaters to select the
compliance monitoring locations. Progress Energy contracted the USGS to operate and
maintain the water quality compliance equipment and to provide data reporting via the USGS
National Water Information System (NWIS) web interface.
0 FKl

The water quality compliance station locations are:
1) Tillery Hydroelectric Plant —River midchannel at the N.C. Highway 731 Bridge located
approximately 0.4 miles downstream of the power plant (Figure 8). This station has
been identified in the USGS National Water Information System website as USGS
0212378405, PEE DEE R AT HWY731 BL LK TILLERY NR NORWOOD, NC (GPS
latitude /longitude coordinates: 35° 12' 02.488 "N, 80° 03" 42.725 "W). This compliance
monitoring station is located on a bridge piling at river midchannel.
2) Blewett Falls Plant— Mid - channel in the tailrace, approximately 800 feet downstream of
the power plant (Figure 9). This station has been identified in the USGS National Water
Information System website as USGS 0212880025 PEE DEE RIVER BELOW POWERHOUSE
DAM NR PEE DEE, NC (GPS latitude /longitude coordinates: 34° 59' 00.925" N, 79° 52'
30.857" W). This compliance monitoring station is a floating buoy system anchored at
midchannel in the power plant tailrace.
The selected location of these compliance monitoring stations was determined through
previous water quality studies conducted at both power plants (ARCADIS 2010b; DTA 2008;
HDR -DTA 2009; Progress Energy 2005a, 2006c, 2010, 2011).
The NCDWQ personnel verbally agreed to the location of these compliance monitoring stations
during the January 13 field site visit. Progress Energy sent a follow -up letter' confirming these
locations as the compliance monitoring stations, as required by the 401 Water Quality
Certificate stipulations (Appendix B). The USGS installed the water quality compliance
equipment on May 18, 2011 below the Tillery Plant and on July 13, 2011 below the Blewett
Falls Plant.
'Letter to Mr. John Dorney, N.C. Division of Water Quality, 401 Oversight /Express Permitting Unit from Mr. Ken
Kennedy, Progress Energy Hydro Operations. Subject: Proposed Dissolved Oxygen and Temperature
Compliance Monitoring Locations. Yadkin -Pee Dee Hydroelectric Project No. 2206. 401 Water Quality
Certificate (No. 3730, Mod') Requirements.
0 E:3

Figure 8. Location of USGS water quality compliance monitoring station (USGS 0212378405)
at the N.C. Highway 731 Bridge below the Tillery Hydroelectric Plant.
Figure 9. Location of USGS water quality compliance monitoring station (USGS 0212880025)
in the tailrace below the Blewett Falls Hydroelectric Plant.
0V

7.2 Compliance Monitoring Equipment
The USGS has installed YSI 600 CMS V2 sondes equipped with YSI 6150+ ROX Optical DO Probes
for compliance water quality monitoring. At Blewett Falls, the water quality sonde is mounted
to an YSI EMM68 solar - powered buoy. Parameters measured at each monitoring station are
DO (mg /L), DO percent saturation ( %), temperature ( °C), and stream gage height (feet). The YSI
600 CMS V2 sensor accuracy and precision specifications are listed in the table below:
Table 1. YSI 600 OMS sensor specifications.
Parameter
Range
Resolution
Accuracy
ROXTM
0 to 500%
0.1%
0 to 200 %: ±1% of
Optical Dissolved
reading or 1% air
Oxygen•
saturation, whichever is
% Saturation
greater;
200 to 500 %: ±15% of
reading
ROXTM
0 to 50 mg /L
0.01 mg /L
0 to 20 mg /L: ± 0.1
Optical Dissolved
mg /L or 1% of reading,
Oxygen•
whichever is greater;
mg /L
20 to 50 mg /L: ±15%
of reading
Temperature
-5 to +50 °C
0.01 °C
±0.15 °C
Additional information regarding the description and specifications of the YSI water quality
sondes can be found at http : / /www.ysi.com /products.php.
The USGS will periodically calibrate the water quality sondes, at least on a biweekly basis,
during the compliance monitoring season. Calibration of the water quality equipment for
temperature and DO will follow procedures established by the USGS and YSI (Wagner et al.
2006; YSI 2011).
Specifically, the DO calibration procedure is as follows:
YSI ROX Optical Dissolved Oxygen Sensor
1) Place the sensor either (a) into a calibration cup containing about 1/8 inch of water
which is vented by loosening the threads or (b) into a container of water which is being
continuously sparged with an aquarium pump and air stone.
2) Wait approximately 10 minutes before proceeding to allow the temperature and oxygen
pressure to equilibrate.
411

3) Select ODOsat % and then 1 -Point to access the DO calibration procedure. Calibration of
the Optical dissolved oxygen sensor in the DO % procedure also results in calibration of
the DO mg /L mode and vice versa.
4) Enter the current barometric pressure in mm of Hg. (Inches of Hg x 25.4 = mm Hg).
Note: Laboratory barometer readings are usually "true" (uncorrected) values of air
pressure and can be used "as is" for oxygen calibration. Weather service readings are
usually not "true ", i.e., they are corrected to sea level, and therefore cannot be used
until they are "uncorrected ". An approximate formula for this "uncorrection" (where
the BP readings MUST be in mm Hg) is: True BP = [Corrected BP] — [2.5 * (Local Altitude
in ft above sea level /100)].
5) Press Enter and the current values of all enabled sensors will appear on the screen and
change with time as they stabilize. Observe the readings under ODOsat %. When they
show no significant change for approximately 30 seconds, press Enter. The screen will
indicate that the calibration has been accepted and prompt you to press Enter again to
return to the Calibrate menu.
Temperature
1) Thermometers must be calibrated or checked against a calibration thermometer, which
is either certified by the National Institute of Standards and Technology (NIST) or
certified by the manufacturer as NIST traceable (Radtke et al. 2004).
2) Liquid -in -glass thermometers and thermistors must be accurate within ± 0.2 °C. For
both thermistors and liquid -in -glass thermometers, an annual five -point calibration is
required over the temperature range of 0 to 40 °C using a temperature - controlled water
bath and an NIST- certified or NIST - traceable thermometer to ensure accurate
temperature measurement.
3) Two -point calibration checks over the maximum and minimum expected annual
temperature range must be made three or more times per year for thermistors and two
or more times per year for liquid -in -glass thermometers. Calibrated thermometers and
thermistors must be marked with the date of calibration.
Progress Energy will notify the FERC and NC DWQ if there are any changes in the type of water
quality monitoring equipment and subsequent calibration changes in future compliance years.
Progress Energy will submit that information for review and approval and file any applicable
updated equipment information and calibration procedures with both agencies.
21

8.0 Compliance Monitoring and Reporting
In accordance with the compliance reporting requirements outlined in Sections III.A.2 and
III.6.2 the 401 Water Quality Certificate:
"Annual compliance reports will be prepared by Progress Energy and submitted to NCDWQ and
FERC by April 15th of the following year "
The parameters that will be monitored and reported on the USGS NWIS web site for each of the
water quality stations at Tillery and Blewett Falls are: (1) dissolved oxygen (mg /L); (2) percent
saturation of dissolved oxygen ( %); (3) water temperature ( °C), and (4) river stage height (ft).
Compliance data will be recorded at 15 minute intervals and updated on the NWIS web site on
an hourly basis. The data recorded on the USGS NWIS website will be labeled as "provisional"
and therefore subject to revision until after USGS quality assurance data review at the end of
each monitoring season. Final annual monitoring reports submitted by Progress Energy to the
NC DWQ and FERC will be based on the USGS data provided after the final quality assurance
review.
The compliance monitoring season, as specified in the 401 Water Quality Certificate, will be
from May 1 through November 30 of each year. Progress Energy requests concurrence from
the NC DWQ to shorten the compliance monitoring period to May 1 through October 31. The
continuous water quality monitoring data from 2004 to 2010 showed that reservoir de-
stratification and DO water quality standards are met by September to early October (Progress
Energy 2006a, 2006c, 2010, 2011). There were no instances of DO levels falling below the
North Carolina water quality standards by the end of October in the 7 -year monitoring period.
As required by the 401 WQC, Progress Energy will submit an annual compliance report to NC
DWQ and FERC for DO and temperature by April 15 of each year. The compliance report will be
a data file provided by the USGS which will consist of DO and temperature for all recorded 15
minute intervals during the compliance monitoring period; the daily minimum and maximum
DO and temperature values; and the daily (24 hour) DO average for each day. The report will
also provide, as necessary, a written description of environmental or power plant operating
conditions that affected DO levels during the monitoring year.
Progress Energy will also verbally notify the NC DWQ of any DO excursions below the water
quality standards that may occur during the compliance monitoring season prior to issuing the
annual report.
01a

9.0 References
ARCADIS. 2010a. Yadkin -Pee Dee River Hydroelectric Project. FERC Project No. 2206. Dissolved
Oxygen Enhancement Methods for the Tillery and Blewett Falls Hydroelectric
Developments. Phase IV — 2009: Baffle Plates, Aeration Ring, Partial Trashrack Blockage and
Air Diffuser Deployment. ARCADIS, Syracuse, NY. January 2010.
_. 2010b. Yadkin -Pee Dee River Hydroelectric Project. FERC Project No. 2206. Dissolved
Oxygen Enhancement Field Verification Methods for the Tillery and Blewett Falls
Hydroelectric Developments. Phase IV — 2010 Draft Tube Venting, Minimum Flow Tests, and
Engineering Evaluations. ARCADIS. Syracuse, NY. December 2010.
. 2010c. Progress Energy. Tillery Dissolved Oxygen Enhancement Program. Feasibility
Review. March 15, 2010. ARCADIS. Syracuse, NY. March 15, 2010.
_. 2010d. Progress Energy. Yadkin -Pee Dee Hydroelectric Project, Tillery Hydroelectric
Plant. Flexible Curtain Weir Concept to Increase Tailwater Dissolved Oxygen Concentration.
Engineering Report. ARCADIS, Syracuse, NY. June 2010.
DTA. 2007. Yadkin -Pee Dee River Hydroelectric Project. FERC Project No. 2206. Investigation of
Measures to Enhance Dissolved Oxygen Concentrations in the Tailwaters of the Tillery and
Blewett Falls Hydroelectric Developments. PHASE I: Turbine Venting. Devine Tarbell &
Associates. April 2007.
. 2008. Yadkin -Pee Dee River Hydroelectric Project. FERC Project No. 2206. Investigation
of Measures to Enhance Dissolved Oxygen Concentrations in the Tailwaters of the Tillery
and Blewett Falls Hydroelectric Developments. PHASE II: Surface Mixing and Compressed
Air. Devine Tarbell & Associates. June 2008.
HDR -DTA. 2009. Yadkin -Pee Dee River Hydroelectric Project. FERC Project No. 2206.
Investigation of Measures to Enhance Dissolved Oxygen Concentrations in the Tailwaters of
the Tillery and Blewett Falls Hydroelectric Developments. PHASE III: 2008 Reservoir Air
Diffuser with Surface Mixing. HDR -DTA. June 2009.
FERC. 2008. Final Environmental Impact Statement for Hydropower Licenses. Yadkin
Hydroelectric Project -FERC Project No. 2197 -073. Yadkin -Pee Dee River Hydroelectric
Project -FERC Project No. 2206 -030. North Carolina. FERC /FEIS- 0215F. Federal Energy
Regulatory Commission. April 2008.
Mobley, M. H., P. J. Wolff, and R. J. Ruane. 2010. Evaluation of Oxygen Diffuser System
Requirements for Tillery Hydroelectric Plant (FERC Project No. 2206). Mobley Engineering,
Inc., Norris, TN. September 2010.
23

Mobley Engineering, Inc. 2011. Mobley Engineering, Inc. Design and installation of aeration
systems for hydropower, water supply reservoirs and other applications.
http:// www. mobleyengineering.com /home.htmI (accessed on October 31, 2011).
NCDENR. 2010. NC 2010 Integrated Report 5- 303(d) List, EPA Approved Aug 31, 2010. N.C.
Department of Environment and Natural Resources, Division of Water Quality, Raleigh, NC.
N.C. Division of Water Quality. 2007. NC DENR- Division of Water Quality — Redbook. Surface
waters and wetlands standards. NC Administrative Code 15A NCAC 0213.0100, .0200 &
.0300. Amended effective: May 1, 2007. North Carolina Department of Environment and
Natural Resources, Division of Water Quality, Raleigh, North Carolina.
. 2008a. Yadkin- Dee Project for Tillery and Blewett Falls Reservoirs. Rockingham, Stanly
Anson Richmond and Montgomery Counties. DWQ 02010437, Version 02. Federal Energy
Regulatory Commission Project Number 2206. APPROVAL of 401 Water Quality
Certification Modified. North Carolina 401 Water Quality Certification. Pages 11 -12.
September 30, 2008.
_. 2008b. Basinwide Water Quality Plans– Yadkin -Pee Dee River Basin. North Carolina
Department of Environment and Natural Resources, Division of Water Quality, Raleigh,
North Carolina.
2011. Classifications and Standards Unit Home. North Carolina Waterbody Reports.
http: / /h2o.enr. state. nc .us /bims /reports /reportsWB.html (Accessed November 2, 2011).
Progress Energy. 2004. RWG meeting summary notes, templates, and study plans. Yadkin -Pee
Dee River Project FERC No. 2206. January 2004. Progress Energy.
2005a. Yadkin -Pee Dee River Project FERC No. 2206. Intensive temperature and
dissolved oxygen study of the Pee Dee River below the Tillery and Blewett Falls
Hydroelectric Plants. Water Resources Group. Issues Nos. 7 and 8 - Lake Tillery and Blewett
Falls Lakes and Tailwaters Water Quality. November 2005. Progress Energy.
2005b. Yadkin -Pee Dee River Project FERC No. 2206. Continuous water quality
monitoring in the Pee Dee River below the Tillery and Blewett Falls Hydroelectric Plants.
Water Resources Group. Issues Nos. 7 and 8 - Lake Tillery and Blewett Falls Lakes and
Tailwaters Water Quality. November 2005. Progress Energy.
_. 2006a. Application for license. Yadkin -Pee Dee River Project FERC No. 2206. Submitted by
Progress Energy, Raleigh, North Carolina.
hz!

_. 2006b. Yadkin -Pee Dee River Project FERC No. 2206. Monthly water quality monitoring
study of Lake Tillery, Blewett Falls Lake, and associated tailwaters. Water Resources Group.
Issues Nos. 7 and 8 - Lake Tillery and Blewett Falls Lakes and Tailwaters Water Quality. April
2006. Progress Energy. April 2006.
_. 2006c. Yadkin -Pee Dee River Hydroelectric Project FERC No. 2206. Continuous water
quality monitoring in the Pee Dee River below the Tillery and Blewett Falls Hydroelectric
Plants, May- October 2005.
_. 2007a. Comprehensive Settlement Agreement for the Relicensing of the Yadkin -Pee Dee
River Project. FERC Project No. 2206. Progress Energy Carolinas, Inc. June 29, 2007.
_. 2007b. Application for Water Quality Certification pursuant to Section 401(a)(1) of the
Clean Water Act. Yadkin -Pee Dee River Hydroelectric Project, FERC Project No. 2206.
Submitted by Progress Energy, Raleigh, North Carolina. May 2007.
_. 2010. Yadkin -Pee Dee River Hydroelectric Project FERC No. 2206. Continuous water
quality monitoring in the Pee Dee River below the Tillery and Blewett Falls Hydroelectric
Plants, May- October, 2006 -2009. Progress Energy. December 2010.
_. 2011. Yadkin -Pee Dee River Hydroelectric Project FERC No. 2206. Continuous water
quality monitoring in the Pee Dee River below the Tillery and Blewett Falls Hydroelectric
Plants, May- October, 2010. Progress Energy. December 19, 2011.
Radtke, D.B., Kurklin, J.K., and Wilde, F.D. (eds.). 2004. Temperature (version 1.2): U.S.
Geological Survey Techniques of Water- Resources Investigations. Book 9, Chapter A6, Sec-
tion 6.1, 15 pages (accessed July 28, 2004, at http:/ /pubs.water.usgs.gov /twri9A6 /).
Ruane, R. J., M. H. Mobley„ C. W. Almquist, P. Gantzer, J. C. Knight, D. F. McGinnis, and P. J.
Wolff. 2011. Yadkin -Pee Dee Hydroelectric Project No. 2206. Tillery Hydroelectric
Development. Dissolved oxygen enhancement field verification methods for Tillery
Hydroelectric Development. Progress Energy. December 2011.
Wagner, R.J., Boulger, R.W., Jr., Oblinger, C.J., and Smith, B.A. 2006. Guidelines and standard
procedures for continuous water - quality monitors — Station operation, record computation,
and data reporting: U.S. Geological Survey Techniques and Methods 1 –D3, 51 p. + 8
attachments; accessed April 10, 2006, at http: / /pubs. water. usgs.gov /tm1d3.
YSI. 2011. 6- Series, Multiparameter Water Quality Sondes. User Manual. YSI Incorporated.
Yellow Springs, OH.
PV

Appendix A
Yadkin -Pee Dee Hydroelectric Project No. 2206
Tillery and Blewett Falls Developments
401 Water Quality Certificate

�0F W ArFgQ Michael F. Easley, Governor
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
Q Y Coleen H. Sullins, Director
Division of Water Quality
September 30, 2008
Mr. Charles Gates, Vice President — Fossil Generation
Progress Energy Carolinas, Inc.
410 S. Wilmington Street
Mailcode: PEB 7A1
Raleigh, NC 27601
Re: Yadkin -Pee Dee Project for Tillery and Blewett Falls Reservoirs, Rockingham, Stanly, Anson,
Richmond and Montgomery Counties
DWQ #2003 -0147, Version 2.0; Federal Energy Regulatory Commission Project Number 2206
APPROVAL of 401 Water Quality Certification — Modified
Dear Mr. Gates:
Attached hereto is a complete copy of the 401 Water Quality Certification No. 3730 mod] issued to Progress
Energy Carolinas, Inc. dated September 12, 2008. The previous mailings dated September 12, 2008 and
September 19, 2008 omitted a final signature page and several attachments of maps. Therefore, this complete
copy with the date of September 12, 2008 is a complete copy of the modified 401 Certification for this project.
If we can be of further assistance, do no hesitate to contact us.
Sincerely,
Cyndi Karoly, Supervisor
401 Oversight/Express Review Permitting Unit
CS /j rd
Attachment
Cc: Mike Lawyer, DWQ Fayetteville Regional Office
Rob Krebs, DWQ Mooresville Regional Office
File Copy
Mailing list from Public Hearing
Matt Matthews, DWQ
Honorable Gene McLaurin, Mayor — City of Rockingham, 514 Rockingham Rd, Rockingham, NC 28379
Gerrit Jobsis, American Rivers, Southeast Division, 2231 Devine St, Suite 202, Columbia, SC 29205
Heather Preston, Water Quality Division, Bureau of Water, 2600 Bull St., Columbia, SC 29201
Adam Rigsbee, Restoration Systems, 1101 Haynes St., Suite 107, Raleigh, NC 27604
Steve Reed, NC Division of Water Resources
Gene Ellis, Alcoa Power Generating Inc., Yadkin Division, P.O. Box 576, Badin, NC 28009 -0576
Ms. Kimberly D. Bose, Secretary, FERC, 888 First Street, N.E., Washington, DC 20426
Don Laton, NC Attorney General's Office
John Suttles, Senior Attorney, SELL 200 West Franklin St., Chapel Hill, NC 27516
401 Oversight/Express Review Permitting Unit
1650 Mail Service Center, Raleigh, North Carolina 27699 -1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: 919 - 733 - 1786 / FAX [phone] / Internet: htto:/ /h2o.enr.state.nc.us /ncwetlands
An Equal Opportunity/Affirmative Action Employer — 50 %Recycled/100/ Post Consumer Paper
W1
NorthCarolina
JVaturallty

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September 12, 2008
Mr. Charles Ciat��, Viw Presidcnt — fossil Cierlmtion
Piog ess hievg} C.4ru1im*, Int_
410 S- Wihuiispvl Slr=t
Mailcode, lT A 7.41
Puduigh. NC 2W301
R>:; Yadleiu -Pee l r Pwir ut for Tiller' and lilevw'en PAUL, Rc:;czvoirs, ktockinghwh,, Swnly, Anson.
Ricbm -nd and Mcm Lgo=7 Counties
DW-Q }2003 -0147, V- '.Tsiam2.0. federal I.nrr�* P.c91.11 FV C~ommis:;ion Projcd NumLvr2206
APPRON4A1,w%4 -01 W uIo r Quality Ceilification- 'vlodifiod
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Attwhcd hm -cto is a copy ofC mi ftcation No. 373CI,rodI issued to pro esq 1-'li�r�a Catulina, Inc_
c awj -9*PtcmLxr 12, NO& L.i w1dililm, you sJiould get Any whcr fcdcral, state or inept] ly'amits before
YOU 84 Hl--ml midi your pm7leci indudug (bLx llOt liraitewl vi) Solid Waste, ge6nm and Erosion
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AJ,Im Rig, b", RmloTaifyii SYsIrnl& I I F) I Tlii.yne4 SIT"', 91jilo 107, Rriki�ll, NC
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Don Tnion, NC .horn {:}' GUI-ICTA 'S 0-'iNC
Jl n 5134I'M, RIA43T Alllomcy, Soushorn Environmaital Law Center, TX IrVesi Frank'in
9lTft!',: TTill, NC 27516

NORTH CAROLINA 401 WATER {QUALITY CERTIFICATION
THIS CERTIFICATION is issued in conformity with the requi- ements cf Section 409 Public Laws
92 -500 and 95 -1'.7 of the United Stdes and subject to the North Carolina division of Water
Quality (NCD Q; Regulation6. rn 15 N AC 2H. Section 0500 :o Progress Energy Carolinas,
Inc. fa cant rue the operation of hydrepnvrer darns at Tillery and Blewett Falls Reaervoim in
Stanly, Anson, Rjdfimond and Montgomery C oun-.i @ &, North Carolina. pursu*mI to do avplication
filed on the 11th day of Mays of 2007, the Gomprehensive Settlement Agreement sated rune 29,
7047 9.11 in addi' -ional correspondence received December 13, 2007.
Tt7e application a d Supparting documenkai6on provide adequate assurance #h at the D opcsed
work will not result in a viplation •af applicable VVater Quality Standards and discharge
guidelines. Therefore, the State of Varth Carolina certifies that this activity will no-. vialale tf-e
applicable portions of SeCtDns 301, 302, 303, 308, 307 (if PL 92 -500 and PL $5 -217 if
cona4cted in acoordanaa with the application, the supporting documPntari'M. and conditions
hPrPinaftr:r qel forh
This approva! i5 art y valid for the purpose and design submitted in the applicaton materials and
as d(�scdbed in the Public Notice. I` :he prajeat is Gn$nged, a new application for a n8w
Certification is requires. If the Vopetty is sold, the new owner must be given a copy of the
Certification and approval letter and is thereby r4lsponfiible. forcamplying with all conditions of
this C: Any rewowner most notify trie Division and request the Certification to issued
in their name. Shovid wetland or stream fill be requested in the future, additional womperrsatory
mitigation may be required as 0e60ribed in 15A NCAC 21H .4535 (h) (6) and (7}. If any plan,
revisions frorn the approved site plan result in a change in steam or wetland impact o; an
increase in impervious surfaces, the NCDVVQ shall be notified in writing and a new app ication
for 401 Ce •tifisation may be required. For this approval to ha vaN7, oompliance Vrith the
conditions lisred r>aIdw is req,iired.
Gonditions of Certifcatlon:
1. No waste. spoil. solids, or fill of any kind shall oc6ur in wetlanda waters. or riparian
areas beyond tho fdbtpnrrt of the impacts dep.cted in the Ceitifi�;akwn. All
construction activities, incl iding the design, installation, operatics, and mainrpnantp
t,4 sediment and erosion -conirdl BpSt Management Practices, shall be performed 9p
that no violaf ens of state water quality standards, statuter, or rules occur:
2. Sediment-and wosirin control measures steal not be plat =d ii wetlands orwaters to
the maximum extent practicable. If placement of sediment and erosion wantrol
devices in wetlands and waters is unavaidahl4, they shall be removed and the
natural grade restGred within six months of the date that the Di}iision of Land
Resources has released the projg.rt:
The Applicant shall identify and fe.'3Ort in writirrp existing and prcpo6ed consumptive
uses to NGL)VVQ and the NC Division of Water Resources (NGIJWR), The Applicant
&half report the existing or projected (as appropriate) average consumptive
wi!hdrawal and maximum capacity fur each withdrawal- The applicant shall report
existing c,:rarisumptive uses to NCDWQ and NCIDWR within 60days ofthe
acceptanne of the Liwanse and shall report proposed new or oxpardod ooneumphve
uses tc NCDVVQ And NCD R within 30 day6 of rtiueiving a request for the proposed
=I

t)ow oe expanded withdrawal and before submitting any requests to Federal Energy
Roguldtory Crjnerniy�!Un -;FERC).
4. This Gertifiratinn does nntgrant or affirm any property rrtPub, license or privilege in
any waters or any .19 ht of use in any waters. Tlr;e CeryificoG9n doe@ n9t auftrize
any person to intarfere with the riparian rights, littoral rights or water u5g ri -ght6 of any
other person, ono this Certification does not crcato any proscriptive right or any righl
of priority regarding any usage of water. No Derson shall interpose his Certification
as a deferse n any action respecting the determination of riparian or, litto-al dghis or
at[ iei water use rights. No consumptive user is deemec by virtue of this Certifiration
to possess any prescriptive or other right of priority with respect to any other
consumptive user ragardlass of the quantity of tho withdrawal or the date on which
the withdrawal was Initiated or expended. This Certification issues on the express
understanding of the NC Department of Environment and Natural Resources
(NCDENR} that Dumuantto Federal Power Act secti on 27, 16 U.S.C. §821. the
License does not establish or determine a proprietar/ right to any use of water. ft
pstaNlshes the naluep. of the use to which a prop'ietary right may ti�, put under thp.
Fede'21 Power Alt.
Cantir�uinq Cor��lionC9:
Progress Energy OarDlinas, Inc. shall conduct its activities in a manner consistent
with State water quality standards (including any requirements resulting from
compliance with s:ect.on 303(d} of the Clean tiNater Act] and any other appropriate
requirements of ;state law and federal law. If the Division determines That such
standards or laws are not being met (inciudirig the failure to stistaln a dorignated or
Achieved use) or that State or federal law is teing violated: or that further conditions
4 r 000--5r.Ary to at6um co mpliar c , the Division may reevaluate ar.d modiy this
Cerlific0on to includa conditions appropriate to assure compliarcewith such
standards and requirements in accordance with 15A NCAC 2H.05C7(d). Be`ore
n•odifying the Certification. the Division shall notiy Progress Energy Carolin88. Iny
and the Federal Energy Reg t,latory Commission. piavide public nonce in accordance
with t 5A N(-AC 7H 11503 and prrivide opportunity for public Bearing in accordance
with 15A NCAC 2H.0504. Any new or revised conditions shall be provided to
Progress Energy Carolinas, Inc. in writing. shall be provided to the Federa Energy
Regulator {Corr mission for mferenC9 in any Permit or l_cerse i ssues by that agency
and sha1I aIse become conditions of the FERG License for the project. In addition. -f
the DO enhancement program as outlined in the Re licensing Agreern9nl does not
result :n meeting the DO or ternperakure water gvIility standard, they this Condition
shall be triggered to rest -It in addit °anal rneaewres to ineet these standards. Provided
�urther, if the Division devalo and adopts standard success criteria for fish similar
:a the aquartic rnacrotyenthos criteria referenced at Condition 7.e.i. of this
Certification. this Condition may also ho triggered to incorporate said standard
success criteria.
Miti ap tion:
b. Siream protection, mitigation and enhanoemprrt measures as specified in
Sections 2.5, 2.6 1.1., and 2.6.2.1 of the Corn prehensive Settlement Agreement
dated June 29 2-a37, small be implemented. NCDVVQ shall be copied on the
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property transfers. leases, and any relatec restrictive c;overionW,, ror Lhe property
descnhed in the C(,mprwhenfirvp Spttlompnt Ag reemant dated June 29, 2f}07.
Other Cond,tiorl*
7. Aquatic" Life Monitoring
Progress Energy Carolinas, Ira. shall coriduC1 post- Iiuming moniicr Pg or aquatic
life bel:)w Tillery Dam as ovtllned below. The purpgsi� of #ha rnonit3ring is to
doeuirtient the conditiDn of the aquati-2 corriinunity in the Pee Dee Riverf om Tillery
Dam to its confluence wish the Rocky River In addition to the wale quality
monitoring as specified in the Comprehensive Settlement Agreement dated June 29
2007, the following biological monitoring shall be required by PragrB35 Energy
Carolinas, Ina as outlined in the January 18, 2007, lotker leom John Dcimoy of
NCDWQto John Crutchfield of Progress Energy Carolinas Inc. ;subject: Biological
man itoring below Lake T Ilery to meet -grater qual ity siandards) end the April 12,
2007, Ieder 1-om Phillip J. Lucas of Progress Energy Carolinas, Inc., to John Dorney
cf NCI)VVQ responding to the Juna29, 2007 letter Lsubject: Progress Energy
Carol Pas, Inc. review and comment Dn proposed biological monitoring below the
Tillery hydroel,& Jri0 pl$M). inolAing enclosure 1 'Progreso Energy Caroiinas Ina
Demiled Technical Comments Regarding Proposed NCDWQ Biological Monitoring of
the Pee Dee River from Tillery Dam to Rocky River Confluence." Progress Energy
Carolinas, Inc., sliall suarnit for NCDWO written approval a detailed monitoring plan
inc udi-ig a specfic monitoring schedule, that adcresses. at a minimLIrn, the following
sterns:
a. Iftnitoring Bites - Two sites (7Z1 an T7_2) shall be used wth the exact
monitoring I0Cation5 selected after consultation and a site visit by NCD O.
h. Frequent y of Monitoring - Pre-new license and post -new Iiciense bio1439ioal
monitoring shall be conducted to establish a t)dselinQ coridition for the
determination of changes attributable to, among 3ther things, improvern-�nts in
flow and dissolved oxygen. Pre -new license conditions shall be determined
prior to implemenka;ron of ticensec rrinimum flax, and dissolved oxygen
imolovernents from Vie project. Post -near license sampling shall t►e condreted
on three {3'1 year intervals for at least four (4} oycle& with written reports
provided to N DbVQ. Forlotivirc Lhe Subriidlal Pr ttiy wiilleri rt�porl folkrvrinq the
fourlh LyuIe_ NCI)%NQ and Progress Energy Carolinas, Inc. shall consult
regarding the need for an.:i arty rharrgPt to fi,tt)rg mQnitarir1g.
c. Type of Monitoring - Aquatic macrobenthas man itarin-j shall Lie conducted
osir-9 rnettrodolc�gy approved by NCD' .'JQ Fish community sampling shall be
c❑nduc,.ad u6ing methodology used in the 2004 shallow slater study. .r,dludirc
tote barge electrofisl•ing, bacXpaok etettrcfishing, and seining. In addition, the
standard physical and chemical monitoring ihat is r3uti 7ely done during
iriauiabentho5orfisr sampling shall be conducted
d Timing rf Men toring - Monitoring shall be conducted during July pr Avgu5t of
the years when it is required, and each sampling event shall conducted
during the game three week windcwv dL,ring Ju.y or Aug usl lo r -truce variatOirty.
e. S_ccessfReaovary Criteria
i. Aquatk: Mincr9benthos - Success criteria for aquatic marxalowtho& shall be
the stanoar:l NCDWC[ cualitakive raking system_ Classification of the
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con7n7uni�y at east as 'Goad -Fa r' shall be deemed successful for aquatic
macrobenthos.
ii. Fish - Fish monitoring data shall be repc red in a farm at to be approved in
writing by NCD4VQ in order to evaluate the response of the fish camrnuriiy
to higher flows and higher cissolved oxygen levels. N I) %NQ may develoo
success criteria forfiish, and Pfog Mss Energy Carolinas, Inc.. will be
afforded an opparturr,ky to renew and Comment o7 success criteria
ceweloped by N O'" before the modification prausion cf Condition S of
Certification No 3730 mods is rigginrod.
Trigger Date for Biological Criteria Evaluation - Attainmen, of macrobentlDs
success criteria shall be measured using analytical data obtained from a
sampling event conducted during ar before 2074. providpd that the 2024 trigger
date may be extended upon a sgawing by Progress Energy Carolinas, 1q--., t -lat
uncontrollable conditions, 6urh 96 Exton -;iod drought or Chemical or mvage
release, inte -fered with attainment of the success criteria. Upon such shaving,
MCDWO shal set an alterrieitiae date.
E. Dissolved oxyrderi mi)ndr3ring acrd improvement -- Improvements to the dissolved
oxygen in 'he Yadkin River shall be done in compliance with the Cornpm.hpnsivp
Saltlarnent AQree-nent. however, if dissolved oxygen levels are less than the
applicable water quality standard after those improvements) Progress Energy
Carolinas, Inc. shall propose additional meosuros to NODWO in order to meet that
standard_ Such measures as agreed upon in wriling by NCQWQ. shall be
imple- nenked by Progre�9 Fnprgy Carolinas, Inc. at an agreed -upon schedule.
9. Comprehensive Settleme -it Agreement - The Corn pre I-ensive Settlement Agreement
dated June 29, 2007 is hereby incorporated by reference into this Certificol on, wth
the exception of Sertions 2 4 and 2.E (exoept for 2.6.1.1. and 2.6 .y.) of the
Comprehensive SE)tt1$ment Aqi Bement dated June 29, 2007 The 4ndiCions of
prtifiratic•r No. 3734 mod1 shall control over cond in Ihre Comprehensive
Settle men, Agreement dated June 29. 2(W. wl3ich are inconsistent with this
Ce,tification.
10. Progress Erergy Carolinas. Inc., shall collaborate with the M. C VVildlife Resources
Commission to makEp boat ramps at Biewetk Falls Lake aoaessible for public boating
use over the range of elevations up to 4 feet below normal full pc rd a evation (1Te 1
ft. '1929 NGVD datum).
11. Progress Energy Garolirnas, Inr,. shall notify NCDVVQ inwrikinp withi -1 5 working days
of discovery of any deviations to the law rakes and lake Tavel fluctuatio-is as set forth
in the Com pre hensma Settiement Agree met. t)eoreased flow shall be restored as
soon as praCl.til to Ihc� written satisfaction cf NCMQ.
2. NCabVQ sha11 he copied oar the fish and eel Dassage scMeoule.
Thetallowing conditions are taken from the Ccrn prehensive 5ettleniont Agrearnent dated
Jung 29, 2007 and are hereby incorporated as conditions of this Cartif4cation.
1. Minimum Instmarn Flows and Other Stream Pr=ction Measures
A. RiVer Inflows from APGl's Yadkin µydroalactric Project
4
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Progress Energy's obligation to meet the minimum flow releases described herein is con,hngen.
upon Pmgr"o Energy's Trllery Developmenk.receiving epecified rninir'Um itrnx releasee 'Fprn
Alcoa Power Generating Irrc.:s Yadkiri : lycr,�clectric Project. The `allowing tipecil`i&J minimum
levels of inflow to Lake Tillery -rom Falls Dam are rrecessa ry for Progress Energy to r: ie--t i(s
minim4im flow abligatioh3:
February 1 to May 15 -2,000 Us as measured on an average Gaily basis'.
May 16 to May 3' —1,500 as as reasursd On an averse daily bdSis
June 1 to January 31 —1,000 cfs as measured on an average daily basis.
B_ BleWOt Fail& Plant
I _ MinlmUrrti Flew Regirria
From February 1 through May 15 of each year, the continuous minimum flaw will be 2,4CC efs,
as measured atthe existing USCSgage at Rackingham. toenhance spawning habitat in the
Pee Dee Ricer dasnstream of the Blewert Falls DpvNopmP. nt Prom may 15 ty'ough May 31 of
each year, a continuous minimum flaw will be 1.800 cfs and for the remainder of the year. June
1 through January 31. the continuous mi aim um flow will be 1,24a cfs, a 1 subject to allowaole
variances described belax. Th is CertiflcaUcin establishes a higher priority on the maintenance of
minirnum flows, than the mnint�nanoe of reservoir water leve s. Therefore, intequently, events
may require the prioritization of rtYaintaini'1-y minimum flows aver the reservoir water levels
identified in Section II of the Comprehensive SpillpmpntAgreement.
2. Flow Adjustments to Enhance Fish Spawning
Progress Energy shall operate its Blewatl Falls Facility during certair times of the year in a
mahner antended to enhance fish spawning conditions downrtrearn of the Blewett Falls
Development as eescribed and defined below. These time piariods art mfe -red to herein as
'flaw 8djustrrerit operations' and they shall occur each year as either (a) one 14�tay and one
10 -day period or {e1 fivp 5 -clay periods In any event, these periods of irna adjustment to
enhance spawning will be araoterized by the to'lawing.
Flaw adjustment operatic ns shall oo wr between February 1 and May 15.
-hg, specific time periods in each year will bin decided upc.r by reaourae
agencies, ProgroaS Fnergy, and Alcoa Power Generating 17c. (APGI'i -
cgll"t -uly, the'Spawhing Flow Management Taanr'. Other eritities able to
demonstrate relevant fiskigri5 expertise may participate in thesediscussi2ns, If
the vptian of one 14 -day per od and one 10 -day pprlod is r rl-Dsen Progress
Energy must be notified of the. specific dates at least 14 days prier io the stad of
each pericc. ff the option of rive 5-day periods 18 chosen Progress Energy must
be notified of the antira schedule at least 14 days in advance of the start of the
first of the 5 -day peri ods.
Pen ads of flaw adjustment operations shall be chosen by the Spawning Flow
Management Team based on interpretatior of relevan, factors that might iP..clude,
but are not limiled to. water temperature and weather data, projected inflow
conditions, and observatiarrs of fish spawning behavior. If f7e option of five 5 -day
periods is implemented, two of thino per ods must occur between April 15 and
May 15.
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• Because of concerns regardii)g the predictability of inflows over longer periods of
time, the indiviouAl flow adjustment periods rnuak be separated by at least one
wook. o rless otherwise apprmued by Progress Energy
+ t` a period of unusually low inflow to 13 lewekt Falls Reservoir br a Low Irflcw
Protocol ,'LIP') perod occurs during a previously 6elected flaw adjustment
operatics period, the release of the -equirEW rn nimr.m contiruous flour (or in the
(,.nsip of an LIP eye-it. the LIP P( m) will still be considered a flow adjustment
period.
If a period of higher inflow to Bleweft FaIIs Reservoir occurs during a ~elected
flow adjustment operation period, wherein itiere is a cvnbnuous operation of all
C.omrnercially available turbines in the Blewett Falls powerhouse, po"iDIy
accompanied by additional spillage over the dam crest, this period will count as a
flaw adjustment period so long as any interruptions in the Continuous operation of
.a 11 E�ornmercially avail2bla turbines are infrequenkarid unscheduled.
If a anod of inteernedinte inflow to the BIewDtt Falls Reservoir ocimrs (flags in
the ange of 3,0x4 to UDO cful. Progress Energy will manage reieases at the
Rowetl Falls powerha.ise a8 follows:
{1) kf unregulated tributafy inflow to the Pae Dee River above Blew attFalls
(particularly from the Rocky River) changes signrfican" during a
d as ignated flcw adjustment aperati¢rl por od, Progress E�nefgy can
respon -1 to the so changes in flow as needed to ma+i "e reservoir
ope•ations by increasing or reducing the number of turbines in operation
witttiLiut considerat an to the limits described below in {2) through (5). This
wnuld still be cc- i5iderecl a flow adjustment period
t2) Except as identit-ed ir. (1 ) above. the upramp lime of each turbine at
Blow; tt Falls will be no less than 30 minutes from off -line to full gate.
(3) Except as Aentified in (1) above, the down ramp time of each turbine at.
Blewett FaIIs frrarn fu'I gate to off -line will be in acomrdi�nce with the
following guidelines:
i. ,after the first operating unit is taken off -line, the seLwmd operating
unit to me taken off-line shall riot be taken Off -line for at least two hours
after the first operating unit was taken oft -iine.
ii. After the second operatioq unit is takers off -Iine, the third operating
unit ko he taken off -line �1fall not betaken off-fine for at le4%st four
haur6 aRer the second operating unit w99 taken off-line.
iii. After tre thi d operating unit is taken aft -line, the fourth aperaling
unit to be tak -an ort -Iine aha l not be taken off -line for at least six hours
after the 'In ird opera_ing urnk was taken off -Iine.
(4) On the first day of any flow adjustment operaton Ins rod, Blewett FaIIs
must cornmenoe such related opraticns no IaWthan 8 a. m. to rttill be
considered as a fu11 day of flow adjustment opera'ian.
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(5) On the last day of any flow adjustment coe,atior, pericc, Blewetk Falls
-nits jan begin to be taken off -line no earlier than 4 p.m. By example. the
schPdulp t]Qlnw wnuld hP cnnsidemd a Full day of a diesignated flow
adjus-rnent operation period if it were the last day of such period:
(i) d PM — go from 5 units to 4 units
(ii) 0 PM — go from 4 union to 3 unils3
(iii) 10 PM —yo frvrn 3 u,i kk k0 2 urlikS
(5) If the five 5--day flow adaustment operatic r. periods are chosen in any
give-i year. each paned sVall begin a i a Monday rnarning and enj an a
Friday evening.
(7) If t fe one 14-day and One ' 0 -day peJod is Chosen in any given year,
the actual dates shall be such as to minimize the number of weekend days
within the 14-day pericc. Far the 10 -day period, there will be na more than
2 'weekend days
All decioion9 to be •made by the Spawning Flow Managemert Team as outlined in this section
shall roquire corieer,Aws 3s apaofiaally defined as follows in he Comp- ehensive Settlement
Agn9emenl:
A resolution; bused on wnbenius shall have either the unanimous support or all
Parties, or at leasr no nppnsitinn frn-n Fkny Party If n Pary has no object on to the
resolution but does not specifically endo fw it. the LOCK of 0ppo6ition shall be
cronsidered to be suppa•t of the resolution.
Progress Energy will prepaca an annual report of the operations of the $lewett Falls
DG- Mop~fent during the F owAdjustmenj Qpefatwn peiiod!i� ;onsisking of meeting notes_ flow
records from streamflow gages. and plant aperations. The opp-ations M the 'rillery Plant during
the FI{rw Adjustment Period wil be coordinated by Progress Energy and sutlect to dispOtoh 1y
Progress Energy in accorda nice with its system needs.
The first year of •mplemenkation of the Flow Adjustment Operations shall be tho calendar year
following the year of licenso issuance. Aftcr five yeerr, of Flow AdjuBt rent Operations, the
Spawninq Flow Management Team shall evaluate the Flow Adjustment Oper¢kipiis and -J awe op
recommercied changes for consideration by the resou -ce agencies and Progress Enp•gy. Rp-
evaluation at 5 -year interva s may occur if dotprmined neressary anc if agreed to by tha
Spawning FIQW M1anagementTeam.
3. Minimum Flow Variance
The rninimum fluw regime will allow a variancc for two 5 -hour periods each year to recuoe the
minimum Mow release to just lea -(age f low fa' tasting Black -start capability of turbines at the
Blewett FaJIs powerhouse. These black -start tests will be restricted ro o•: Cjr onl in October.
November, Decsrnu4w. of J; rnua•y, when environmental effects of low flow for a �:-hour period
are expected to be minimal, f -url:W these tests shall no- bra conducted in October if a Stage I
or greate, Low Inflow Protocol event has been triggered.
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In an effari to properly manage water during unusually law flog C�rldiki0r S, Progre!A Energy
shall W,ctpate in a Low Inflow Protocol (LIP) (see Section I. D). Minimum instrearn flows may
he reduced during these LIP periods in order to conserve wale- resources du1rig pad ods of low
flew in the wai � mhed,
4. Minimum f=low Compliance and Monitoring
Progress Energy will maintain to the standards established by the USGS a cant nuous `low
mon.toring gage at the site of the current Rockingham US GS gage and will provide flaw data to
the public, via the Internet or ather appropriate means, io be updated no less than every two (2;
hours. For the tirs- ten (1 al years after issuance of the New License, Prl:gress Energy tivil
cortract with the US GS for operation and •nairitenance of this gage. Annual reporting of flcyrs
will be n eocordance with normal US CS practices and procedures. Com plianeewith mini-nurn
floors for the Blewe't Fa11s facility will be measured at the Rockingham Sage.
Progress Erie igy will Inailtai-t to the standards estab fished by the U SO S a contmuaus flow
man taring gage at rho site of the currant Rocky River gage near the rnautt• of the Rocky River.
Progress Energy curre -illy pays a portion of the cast of the maintenance of ni€ gage. If far any
reason the funding cf this gag$ by others is lost, then Progress Energy will be responsiale for
the add itiDnal funding necossary to maintain the gage_ However, the !Applicant may elect to
discontinue the use o- UISG5 as the provider of this service after the First ten (10) years
following the issuance of the new Iicanse.
Minimum releases required at the Blewett Falls Development shall be presumed tv have been
met f flews recorded at the streamflaw gage at RocKir!g ham are within 5°1a of the required
m nimum release. so Zang as the 'true -up" pracadure described Wow i5 implomentod Progress
Energy wild p -epere an annual repc-ndawrnenting its cornpliaxewth minimurn reIsaa$s
including any Irue -up" periods. To the extent practicable PrCmresr, Energy will "iru &u p`
minimumflows monthly; that is, Flows falling below thY rninirrnum shall be offi i by flaws greater
tnar7 the Minimum (fiurino mlrti,murn rn"se periods) M the same month for a reasonably
equivalent amount of time. If any irstancas of recorded lower- than - required minimum flows are
not propery compensated for in the month they occur, such compensation will oocuras sobrl a5
practicable in he next month, but no later than the 1 5L day of that month. Progress Energy's
annual report sha I indicate all periods where a "true -u o' was required and show ri aw and when
t-te ;AGaal "true -up' Dacurred. The annual report shall be filed with the MCDEN9 — MrVQ and
1) VR, by March 31 of the fol During year. If any of the resourov agencies have siynirir ant
concerns or oomments art the report. a .ansultotinn rnoc-ting wil, he convened to discuss these
concerns. Such rreet- ng shall be hold within 45 days of the issuance of the report.
There shall be no'4jirning" of t7q minimum f low variance allcr&E -d under this compliance
st,aIdad; that is, under no circumstance shall Progress Energy intentionally or willfully use the
existence of the variance grid trut -up rnechanism to deliberately manipulate minrmum flow
releases fie oninrida with demand for electricity. For example, a consistent record of lower -than-
required ninimurn `:lows during periods of high electrical demand shall Ito cnn�idpred 'gaming.'
Certain LIP events require the rgIease of 925 cfsas the 'critcaIfiow.` TheApplicant5haIL
endeavor to •naintain t'iis target kw, hgwev, r, compliance will have been whiewed if the flow
recorded during this ekrarrt is bet„ragn 900 and 954 efs at the Rockingham gage.
A -11

C_ Tillery Plant
1. Minimum Flow Reginho
Progress Energy will provide a continuoLis year -round rninim,ini ncm at the Tillery Dave opment
of 3gO gTs exyept for a psr.od of eight continuous weeks --an7rnancing as early as March 15, bUt
no Iator than Ma rah 22, when a minimum flaw of 72:5 cfs shall be provided to enhance Amer can
shac spawning. This release of 725 gf6 will sta+t in 2610, or at the Irst passage of Arnekan
shad aaawe Rlewett Falls Darn, whiO-&waris later.
2. Temperature ofMinimurin Flow Releases
Flu-hz released at the JrlleN Deuelaomem fortna purpose of meeting minimum A.)w
requirements will 4e done in such away as to ay6d skimming high temperature surface water
from tho a:5pwnost surface of Lace Ti ley W high Le- nperatr+re gradients are found to occur in
th& upper .six inches of the lake.
3_ Minimum Flow Corn plianceand Monitoring
1"hin 12 months of the New L °cense FiercrmIng Final and Non- Aopealable_ Fragress Energy
will install and maiintain to ttre standards established by the USGS a continuous flow mantorir,g
gage below the Tillery development nea - the State Highway 731 Bridge and wil provide flour
data to the pvlblic�, via the Inte nct or other appropriate means, to be updated no leas than ;Very
two 12) hours. For the first ten (10) years after issuance of the New License, Progress Energy
%vill contract wiiih the USGS for operation and maintenanw of this gage. Annual reporting of
flows wrilI be in acco• dance with normal [i5 c S prar,lir*s acid proce-aures_
Minimum releases required at the I d]ery unvtlopment a•e presumed to have been met if flows
recorded at the streamflow gate near the Highway 731 Bridge are with n 5% f the required
minimum, as Ivrxj astho "tru; -up:' prarcdure doscribed below s implemented. Progress Energy
will propsfe an arnual report documenting its aompliancewith minimum releases including any
'try„ -upj' period. To the extem. practicable. Progress Energy will 'true -up' minimum flours
monthly; that is. flows ;ailing belan the mirtim.im sha I be offset by flaws Uri.alE--r than the
minimum (duri ng minimum release periods) in the rsirne month and for a reasonably equivalent
amaurt pf time. If any instances of recorded kyvar- than - required minimum flows are not
properly campcnsatcd for in the month divi occur, such compensation wrilI occur as soon as
practicable in the next month, but no pater than the 15th day of that month. Progress Energy's
annual report ahali i,dicate all penodr, wcrere a'true -uo' was required and show how and when
the actual ':tru &tjr occurred.
4. Other Stream Protection Measures
Progress Energy has agreed to conserve for lowposes of stream pmtertion vAriDUS plats Of lord
it owns along the Pee Dee River in the vicincky of the Project. C *r rervstion is dGhievod through
cithcr dory ;lion of lands to %L- State of North Caroline or through the plapement of restricAvin
c*vansnts ort riparian lartid$ and witriin shoreline bufferzorieS, Thee rnea5ure5 are d=SGribed in
detail in SBG-ion IV.
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D. Low Inflow Protocol
Progress Energy agrees =a oa.m ply with the requi rem enls of :he Low Inflow Protocol (LIP) dated
February 2CC -1, which was developed as part of the relirensing prcaess. The campletc text Of
the LIP is also attached se, Appendix B for inclusion in ihe401 Water Quality Certificate.
E. Implcmantatlon Schedule
Minimum instrearr, flows wall be commenced within 00 days r3f the rimeip' gf a New Licerse from
FERC that is Final and Non- Appealable, assuming riatAPGF!; rtew heerse has been issued
prior to or concurrew. Nth PrQgm5s Energy's license and thal AP I has commenced, and
continues. the re eases specified ir, Ge,3tion I A.
11, Reservoir Water Levels
A. Blevvett Falls Plant
When inflam to Blevwtt Falls Reservoir are less than approximately 7,440 cfs, Progreyr,
Energy shall maintain a year -round water level regime at Blewett Falls Lake that allow for
fluctuations of up Ic B ft, between alavation 17;2.1 and 178.1 ft. except for system
emergencies and LIP. When flashboards are down ar add ticral 2 ft of draw-down to
elevation 170.1 ft is necessary to safely replace the flashboards.
During the Mass spawning season, April 15 to May 15. Prc -grass Energy wi1I limit water Ieve€
Chdny�-.is to 2 ft to enhance bass spawning except when additional rpsprwir storage is
necessary Tin rn wt mirtim-.jm flow release obligations (minimum [low role a see wi I have
priority over lake elevation6j a• if the flashboards fail. In either of the exceptions roted
above, Progress Energy will endeavor to return to normal operations as soon as reasonably
practical.
B. Tillery Plant
1. Water Lev@Is
Prog mss Energy will tallow a seasonally -based lake Ieval ^nanagemE rnl $Ctedule at Lake
TdIery during the tend of the New License. From December 15 through March 1, lake Icwcl
fluctuations will be limited l0 3 f between 274.3 and 277.3. unless use of rese rvoir storage is
need to meet demand for aleetriCity. If s,,orege is needed for electrical generation
purposes during this period. Progress Energy may use the storage available between
el -evations 272.3 ft and 277.3 ft, rc- suiting in a rraximum fluct.iation of 5 ft. When used for
thesp rawer- rPIatnd ptiWAF s, Progress Energy will normally cycle the reservoir within these
elevation lirn its on a doily ormul"aily taams WgiterfIuctuations up to 8 tt may occur duri ng
sys#om emergencieA, and pokenti arl y be greater du' ng LIP periods.
From Apr 115 to May 15, Progress Energy will limit lake leve changes to 1.5 ft below the
water surface elevation -if the reservoir as measured c April 15 far bass spawning (higher
elevations are acoepkab•e).
Duri ng all Other periods of the year (except flood flag condi-ions), Progress Energy will
maintain lake level fluctuations to genera Iy within 2.5 ft of full pool {elevat an 277.3 h
14
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measured at Tillery Dam;. a7 waekda'ys, and generally 1.5 it of full poc-1 an wee kands and
holidayq.
Z. Maintenance Drawdowns
OnGe- iq every � -yYar period, Progress Energy will sc.ie -Jule a maintenance dravrdown of up
to 15 ft In occur om t_akp Td fry within the #amber '5 to r)P mber 1� timefr#rme. Thit
drawdowq will allow Progress Energy io perform rc -Gtine periedir, rroimtanano dnd ga.e
testing that cannot be aocomplishad when the lake level is -i ighar.
3. Public Information on Water Lovcls
Prcgress Energy wil: add a projection of the expected daily water Iov� -S for th3 day or, their
existing 800 - 899-4435 publ.c messaging ser�eice. For the first Fire years of the Nefw Li -camid,
Prcgress Energy will also arovide an annual nctice on November 15 alerting the pub is to
Me dr2VldbWn IiMitfi thWt apply 00x ari npCamoer 1,5 ord March
4_ Emorganay or LIP WatorLnveI Variance
In the case cf an LIP evwt, Lake Tillery and the atcer larger reservoirs in the basin will be
called '.ipcn to use some of their storage to agrno # dowmtmam flaws in a coordinated
manner. Management of flaws and %vater lavels during LIP events are contained in the LIP
attached hereto as Appendix B.
C_ Compliance Munitaring
Annua• reports on lake level compliance will be submitted to the North Ca,ol ra Division of
Waie` Qual ty (N D'NQI and will Include hourly readings of lekc lavols rcoarded at the Wh
the Tillery er,d Uevmft llal s darra.
D. Implement,ati" Schedule
The rkwi resefvsjr level management regime will be initiateswithin 12D d%S of '.he. New
Licenses becorning Final and Non- Appealable.
III, 1Nat�r{3uality
A_ Blewett Falls Plant
1. Tailwater Watar Quality
Progress Energy sha I meet digsolved oxygen standards by Decemtt-r2011. The
implementation schedule inc!udes oompletiwi of fierd testi'tg of DO enhancement options by
Deoember2t}48. and competing successful implementation of the best suited a-0
eriri,hras:ementt,echno Dgi • by Decem r 2D1'
2- Compliance Monitoring
Progress Enor -c r will provi-�Ia monitoring of wetertemperatura and dissolved oxyger.
Tempera -ure and DO monitofing will ocour immediarelyr below the e-id of the Blewett Falls
tailrace with aquiprntnr in -stalled by the Applicant in ao2cirdwic m with prutm:0s approved by
IN
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NCDVdO. Annual compliance reportswi I be prepared by Progress Energy and submitted to
NCDWO and FE RC by April 15th of the fo lowing year.
B. Ti l lery Plant
i, Tailwater Water Quality
Progress Energy shall meet diss3lved oxygen standards by Deceirkhw 2011. Thd
implementation schedule includes completion of Veld testing of various DO e±nhanceme;rt
options by December 20D8, and completing successful implementation of the best suited
DO enhancement technology by December 2011.
2. Compliance Monitoring
Progress Energy w II provide continuous monitoring of water temperature and dissolved
pxygpn ?emppralure and DO mpr1itpring will ootur below ,'hp Tillery Plart wllh equipment
installed by the Applicant in aces- rd ance with protocols approuscs by NCDWQ_ The final
IocaGan of DO monitcdre near the Highway 731 Bridge will be determined based upon
further testing of QO e=nhancement technologies and resulting patterns of DO conce=ntrations
in the Tillery taiMrater. Annual compliance reports will be prepared by Progress Energy and
eubmittea to NCDVw(� and FE RC Dy April 15th of the fa How rig year.
C_ Total Maximum Daily Load Processes
If_ durng the term of tie new hoerse, any Total Maximum Daily Load (TMDL) PFOCOG r, fro
required for the Yadkin -Pee Dee River (or its tributariea) within the Project Boundary of the
Yadkin -Pee Dee Project or - ?n the Fern Dee River imrrrediatiply dewnttri aim of aithar Tillery
Reservoir of Blewelt Falls Reservoir, the Applicant will particiNte in these processes.
Parlivpaor) would he exacted to include, for example providing any existing water quality
sampling or flow release data and participating in relevant stakeholder technical teams
IV. Additional Stream Protection Measures
For the purpose of providing additional protection to steam and riparian r.abitata withiri the river
corridor potentially affected by Project opera ions, Pr rig ikrsa Energy will undertake cerain
measures a5follow5-
(1) the donalion to the State of North Oerolina of certain parses of Undeveloped land
owned by Progress Energy borderirg the Pee Dee Fiver;
(2) the placement of restrictive covenants for conservation purposes on curtain parcels of
undeveloped land owned by Progress Energy adjare tto Project- affected waters; and
(3) the :eaaing of certain landr, owned by Progress Ene;r�y to the State of North C iAl01ii, a for
the tern`, of the now license.
Each of the measures referenced above erg more fully described below.
12
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A_ Lanft to Be Donated to the State of North Carolina
Within five pears of tyre its -itmw gf the New License fur the Project that is Final and Non -
Appealable, Progress Ena,gy will dGm4dto to tires sate of North Carolina various trad6 of land it
owns along file Pee Dee River below Blewett Falls Darn on both the east dnCl west rive -banks
extendirg Toni 3leweti Fa Is Dam to belewthe Highway 74 bridge and including lands adjacent
to the highly valued river weals located below Highway 74. These Iands also include the
abbro Slopes area above Hig Map T4 and valuable riparian and wetland GDrnplexes on the
East and Nest river banks. These lares to be donated, which have a total - aveege of
approximately 1000 atrez�, are depicted in the attached Appendix C.
Within five years of the iasjance of the New Lioense far the Project that is Final and Non -
Appealable, Pr❑gress Energywdl also donate tithe State of Noah Carolina lands it presently
awns along the eastern bank of the Pee CLOO River extending downstream Tom the Highway
731 bridge for approximately four (4} c, nfiguous rnile5 These lands to be donated, which have
a total a:;reage of approximately 3�6 acres and will provide a protected riparian corridor along
the east shore of the Pee Dee River, are depicie ?d in ilie attached Appendix C.
UnbI lthese lands are donated to the State of North Carolina. the Parties agree that interim land
ma n a9prinn. nt by the Applicant will use reasonable efforts to conform to the fotlowing forestry
management pre -Gti�es where tim bering is scheduled:
(1) For loblolly dine plamations that are 34 ar more years old, thin to approximately 30
tmc&lacras.
(2) For pine!- ra,tdwood mixed stands tha- are 30 or more years alc, after aonsultaEtion with
NGVdRC:, thin 1-r� approx ma-ely 30 treeslacrs.
(3) For 15 to 30 year old stands of loblolly pine, lhin 'p approxirna!ety 64 trees;acre.
(4) Rasa ve tho ability to clear cut parcols up to 25 $orbs in size where best maraaernent
practices would dictate (not including any anvironmentally slgnificart areas) but orly
after consultatfon with NS RC and DWQ.
(5) Leave an and !Au ibed buffer of not less than `00 fa-ar in width along the Pee Dee River
and along troth sides of any streams
(s) PmdDminantly hardwood stands will nit be timbered.
The Applicant represents that it is responsibia for providing reliable electric service to its
customers withi7 North and South Carolina. To that erid, from tima to fime! the Applicant
constrr,cts electrical transmission lines within its service area. The Applicant represents that
such lines are located only after :,ohsideration of many factor$, ii�cluding potential impacts to
homes, businesses. schools, roaca, aria; other infrastructure, cultural anc historic resaI-irces;
sensitive e-iviron- nental features and n2trrral areas; and other fac'ora, Nothing in this 40"
Cerrifim;Tion (1) is intended specifically to prohibit the Licensee frorn planning, designing, and
constructing a transmission or distribution fine through, aver or advss lands described above by
thEs Cagifiootiar, or (2) shall obviate al)y duty to obtain all noGessary regulalary, env-mninenial
or othe{ approvals. The parties :ecogrmre that the rights, duties, nbllrgations of this 4-01
Cfertif Gation and the actions taken tr11Mt,ant to this o--rlificate (such as the prese- vation of lands
13

described herein) maybe considered in any proceeding regarding atranslnissron ordntnbutian
lin °.
Each pa�ty assumes responsibili_y For its awn assts associated with deed transfers descrbed
herein.
B. Lands Subject to a Restrictive Covenant
Progress Energy w•II place a restrictive covenant tar conservation purposes on certain lards it
owns known as the "Diggs Tract' along the Pee flee River be aw the Highway 74 bridge, whin
is depicted in the attacf ed Appendix D. Within tw,weWe (12) months of ttie issuance of a New
License for _be Project that is Final and Non- Appealab,e. Progress Energy will execute, deliver
anc cause to be recorded covenants and re5tr0ivn5 establishing a buffer zone adjaceni to the
ever the: would be at least 1 UU- ft=Nide along the entire tract. Within the buffer zone, activities to
be allow --d would be limited to such a,�trfities as €elective clearing and oantrolled bumrng in
acoordanae with a forest mor egement plan approved by NCDENR, limited unimproved fc-ot
trails nak :U exceed 4 fk i7 wifth and a single beat access point to the river. Foot trails generally
parallel in the river shall be no closer to the river than 50 fe°t. Thera shall be no mvie than three
trails perpendicular to the river within the buffer zone. Except to a000mmedats the above
allowable activities, the following shall be pro hibited within tl'e buffer zone: filling, drainira,
flooding, dredging, impounding olear r-g. burning, Cutting or destroying vegetation, culUvating,
excavating, erecting, overnight camping, r $th,itinC, releasing wastes, or otherwise doing any
vrot within the buffer zone, introducing �xctin species into the buffer zone (except biological
controls pre- approued by NC DVUQ) and from changing the grade or elevation, impai6r}g tie
flew or cirot- lation of waters, red w6nq the reach of waters, and any other discharge or $ttivity
rvauidnq a permit ender clean water a mater pollution oantral taws and regula.+dn8: a8
arneri-Jud TI le lolloviing are euaressly excepted from the prohibited activitign. -;a) cumulatively
very $m all impacts associated with hrinting, fishing, and similar 1eor�-.ali -3)nal or educational
activity, consistent with the continuing natural ccncdiDn of thin property; (b) removal or trimming
of vegetation hazardous to persons or property; and (c) restnrat on or mitigation required under
law. No pe rma nent structu res would be allowed within the i00-f,' buffer zone_
Within twenty four (24) morths of the issuance of the New L- cerse that is Final and Non -
Appeatable, Progress Energy wdi also place a -astrictive covenant for conserva`Ion purposes on
Project lards it owma in the Grassy Islands area localed at the upper reaches of Blewett Falls
Lake, which are depicted in the attached Appendix 0 7hie area contains large bottomland
hardwood forests and an oxbow swamp with a large stand of Black Gum. These are highly
valued wetland resources of r --giorial Signifi cance_ The restrictive cvVenant would be defined to
permit only certain rr)r- rnnsurnptive uses of the lands, including fishirk9. hvnLing: hiking. b,rd-
watching, and other low- density recreation active ties F'rohibrted activities ,mill be idienticai to
those desorbed above for the Diggs Tract.
Wilhin twenty four (24) months of the issuance of the New License that is Final and Non -
Appealable, Prog -ess Energy wrll pla .p a restrictive covenant fcr ounserwation purposes on
certain lanes it awns near the mouth of the Uwhanie River, which are depicted in .he attached
Appendix C. The lands to be prote;�ked by a restrictive covenant indudit! (1) those extending
fr -om Dutchman's Creek downstream to the lip of the peninsula on the south side of the mouth of
the Uwhanle River and (2) th4c�p at the upper and of the "bay." created by the above peninsula,
that are classified as of E)egumlt er 2MB as E- ivironmentaMaturat Arpafi in the Shoreline
Management Plan stoppil-y at the first tract of land classified as Impact Minimization Zane Thin
restrictive covenant will allow only certain non -consumplive uses of these lands, such as fishing,
14
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hunting, hiking, bird - watching, and other low- dersiry re.crpariort airtiwifiPS Pr[rhiW6d activities
will be idertical to those described above related to the resirictive covenants to be applisd to the
bu#ar zpna of the brggg Tract.
Until these- lands are protected by covenant, the Parties agree :hat inferini land management Uy
theApplituankwill trse reasona Die ertartsto conform to the fallativirg Forestry management
practiceswherptimhpring SSr;hepuleo:
(1) For Lab ally pin$ plantations that are 3C ar more years old, thin to approximaicly W
trccsfacres.
{2) For pine;horjvv;)L3d rTiuted stands that are 30 or mare years aid, after consultation with
NCVVRC, thin to approximately 30 trees. +acre.
{3) For 16 to 30 year old etande of loblolly pine, thiP. to apDroxi-nately 60 lrccs;accc
{4} Reserwo ,he 0dility to clea-rut pane s up to 25 acres in size where b$st rrioriagerneI
era, tires would [fiotake 6uk rncluding any environmentally signiPfc2nf areafij hur only
after consultation'with NCVVRC and akrVQ.
{5) Leave an undisturbed offer cf not less than 100 feet in width along the Peg Dee R:wer
erd alorg both sides of any stregms.
{6) Predominantly harctNwvA atandswil no- be timbered.
The Applicant represents that it is responsible for proliieing reliable alectric serwil'e to its
Customers withi-i North and South Cargling To that end, from time to time tho Appli" -it
constructs electrical transmission lines within its servme area. The Applicant r$p•esenka that
such limes are located onily after consideration of many factors, inCtr.ding paten -ial mpnmci ir.
Ilorrlek�, businesses, schools, roads, and other infrntructure; Guttural ano historic resaurWS.
sensitive envircin yierrtel features and natural areas; and other factors. Nothing in this 40'
Certificatiarl (1) is intended spech arlytoprahtbitthcA # pliGantfmm plenring, des gning, and
constructing a tranGmie5ion or distribut on line through. over ar acmes lands described above by
this Cerfificaticr or (2) shall obvrake any duty to obtain all nacr:s,.;ary replakory, environmental,
or other approvals. Thin pa fie6 reca9nize that the rights, duties, obeigations of this 401
certifi-cafe and the acticrs taken Dursuant is this Certification (such as Lh(c preserMation of lands
described herein] may be considered in any p.roocodinq regarding atransmissicn or distribLAIivn
line
Each party assumes responsibility for its ovm casts assadated wil h the deed transfers and
resirictive r;,wenants described herein.
C. Lands to ba Leased
Progress Energy will lase to the State of Nortii Carolina for the turn of the new license, and at
the present lease .-ate, lands it Cur iently owns between Morrow Mc)tjMaFn Sate Pat and the
Pei Dag River. whicri lands are depicted in the akwaGhed Appendix E These lands are in Chia
vicinity of Arid include the exisiing beat laurMCri area at Morrow Mountain State Park. -he base
shalt be II2 okiated and executed wi #hint twelve (12} months of the issuance of the New Llaensm
-hat is Final and Nan - Appealable.
15
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V. Otharttilll &caltari9GUr Pratiaction. Mitioation and Enhancement Measures
A_ S;lewett Falls Plant
1, Shoreline Management
The shoreline management practice for Ble vett Falls Lake will prohibit private access, except
normal foot access to the lake across Project lands except at the denigrated public access
areas. By this measure, shoreline management shall focus on natural resource protection to
preserve the largely undisturbed nature of the Blewett Falls impoundment. Additional wrikter
appruva: from DVVQ is req.iiredfor changes to he shoreline management plan.
2. Blewett Falls Lake Sediment Survey
Five years fallowing the issuance of the Now License that is Final and Non - Appealable,
Progress Energy will cond.i:;t a sediment survey in 6lewekt Falls Lake and a gravel recrui menk
surrey in the Blewett Falls Ulwa[er. The grave recruitment survey will repeal the study
conducted by Progress Energy during the relicensing process. If results indicate that there is still
no significant problem retated to gravel recruitment, then Pingiuuu Energy will upndud another
survey after an additional 10 years.
B. Tillery Plant
1. Implementation of Shoreline Management Plan
Progress Energy tvil irnplernent end enforce the existing Tillery Shoreline Management Plan
{SAP} approved by the FERC by order dated November 24, 2DD4
Appendix B
Low Inflow Protwol for the Yadkin S Yadkin -Pen Doe (fiver Hydroelectric Projects
:e'!#7AN
The fundamental 90el of this LOW Inflow Protocol (LIP1 i4 to Cake staged acti7in.5 in the Yadkin -
Pee flea Rivar Basin iie&ded to delay the point at which available water sic rage in the Yadkin
Hydroelectric Project (Foderal Energy Regulatory Commission— FERC Na. 2197) and the
Yadkin -Pee Dee Hydroelectric Projert( }ERR No. 2200 (collectively, projects) reservoirs iafully
depleted while maintaining dovmskrearn flows. This LIP is intended to provide additional tirne to
increase the prot)aNIIky that o sciptation will restore streamllow and reservoir veoov elevations
to normal ranges. The amount of additional time that is gained drlrir,q irnplementation cf this LIP
depends or the diagnostic accuracy of the trigger pa.nts, the am aunt of regulatory flexibility
available to operate the projects, and the affective ness of the project8' operalOm and h9 water
users in working together to irnpk - rnenk required actions and achieve significant Water use
reduetiors_ It is assurneC that watLn.r users in the Yadkir -Pee Dee River Begin not subject to this
LIP must Damply with 011 epplio @ble State and kcal drought response ruirements.
fdlorespecifically, this LIP establishes prvaedures for adjusting operations dunng peripdsof low
inflow to the Yadki n Hydroelectric Project owned and o perated by Alcoa Power Generating I ne.
(APGI) and the Yadkin -Pee Dee River Hydioeleckric P raj ect owned by Carolina Power & Light
Company and ope•ated by Pri5orpsfi Fnargy Carolinas, Lnc. (PE) (c llemwety. Lieonsees) during
16
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the te7n of the new FERC licenses issued r {,r iheye projects. The provisions of this LIP should
be interpreted in A m8nner corisistent with al. ocher provisiorrs of the new FERC IIC4�nS95.
OVERVIEVw
This LIP will be implemented during periods wher there r9 not enough water floruing irrtL) the
projects' reservoirs to meet the projects' Requireo Mininr.a -n Instream Flovis while rraintaining
reservoir water elevatiorks within Normal Operating Ranges This LIP provides trigger po nts and
operating prcceduresthat thr: t iren *ees will foJlaw for the projects. I his LIP also specif.es water
withdrawal reduction measures for ather Ovate -users in portions of the Yadkin -Pee Dee River
Basin.
The L nsees wi11 provide flow from storage in the projects' reservoir 15 to support hydroelectric
generation and to provide Required Min; mum Instream Flaws in accnrdanMp with their
respective nevi FERC: licenses. a idrq periods of nor•nal influx. reservoir watorelevations will
be maintained within their Nor•nal Reservoir Operating Ranges_ During times that inflow is not
odeg4ate to provide Required Minimum Ins`rcam Flowa and maintain reservoir water elevations
wi'.hin kmeir Normal Roscrvoir Operating Ranges, the Lirensees wi11 educe releases for
hydroelectric generation. If resenrpir storage continues to drop and climatalogic o- hydrologic
conditions worsen untirtriggerpoints defined in this LlRare reachel, the LirenseeswilI
implement additinn01 provisions of this LIP, ir4rludirg meeting with the designated agencies and
water users to dismiss the reed for actiorts pursuant tc this Lla. If conditions tivQ -s.en.
progressive stages of this ,IP will allow additional use of the available water storage invenf,)ry,
while conservtng water storage volumes through roquirld reductions in LIP Floes and required
Ndur4iona in water withdrawals.
Implementation of this LIP ar.-� movement between ere various stages are based on
measuremYnts of Stream Gage I hime -Month Rolling Average Flow, U. S. Drought Munito-
Threa -Month Numeric Average, and the High mock Reservarr water elevation. The u.�iIculation of
these tdggom and specific thresholds associated with each Stage are detailed in this t .P
Recognizing that improvemi�nIs to this LIP may be idPntJFl 1 during the now FERC Iicerrse
period, this t I ori11 be re- evaluated as defined in Key Den nit icns, Facts and Assumptions
No. 18.
KEY DEFINITIONS, FACTS, AND ASSUMPTIONS
1. Low Inflow Watch br Loyr Inf ow Conditiori — A period of ti rne whin there is not enCLgh
water flo"!ag into the piofects' reservoirs to maaC he projects' Requ red rAinimurn Iristrearn
Flowswlule maintainingraswvnit water elevation ewrthin Normal ResarvoirOpe rat. rig
Rarges.
2. LIF3 Flows— For the Durposes of this LIP. this terrn referr} to the flows defined in Table E.
3 Required Fdlirli -nurn Instrearm FIom —For the purpc:-ses a.:his LIP. this term includes t4e
minimum fl(lw requirementsi inuJuded in the new FFRC licenses for the projects.
4. Public.rnfomlation Obligations — The L consaag will develop and provide informatics vn their
respoctiv —e websites tc inwebsites tc infprrl the public on re rvoir wafer elevations. projec[ releases.
us2bilit4 Of public access areas. reservoir inflows, rneteorolgyikm l furecros:s, Histnric and
Ac-uaI Strum Cage Three- rdonth Rolling Avsrage FImy calculatior,s, U.S. Drought Morlitor
17
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Three -Month Numerc Average calculatkons, LIP qtqtws.YPD-DrAAG meeting summades,
and implementation of maintenance or ernprgpnry ape-ration plans.
5, S'rsam Gage Three -Month Rolling Avemge Flow — The three -month rolling average of
.Streamflow will be calculated at the fol lowi rig USGS stream gages:
Yadkin R ve r at Yadkin Cc Ilege (0211050b)
South Yadkin River gear Mocksviile (0211KOO)
Abbolts Creek at �_exington {W1 ;1500)
Rocky River near Nvrx' (02125000)
This flow will be calculatec on trie last day of eorh month by averaging the monthly 5yerage of
the u crept n701111 and the two preceding months. The sum of the three -month rolling $verag-[�
far these four gage stations will be cnrnpaield to Ilie Historic Stream wage Three - Month Rolling
Average F ow far the aorresponding period.
fi. Historic Stream Gage Three -Month Rolling Averaoe Flow — The daily flow far each of the
four designated UE G 3 stern gages has been used to calculate a monthly average flow for
the period of record 1S74 thruuyh 2603 Because the USGS only bagan gaging flaws for
Abt33tts Creel( in t9AB. the historical average far this gage will be lased on khe period 1986
through 2003. The histaric three -month rolling Ayerege flaw for each month of the yeas.
presented in Table 1, was calculated on the Iast day of each month of the year by averaging
the morOly average flow for each month and t-ie preceding two montri s The use of the
period of record 1074 through 2DQ3 to calcu lete the his, oft three -month rolling average f ow
will to-e evaluated every five years dui ir,9 the review of ti is LIP (see Key Def nitions, Facts,
.9nd Assumptions No. 1t3).
Timblo 1. Historic Stream Gage Three -Month Rollin Avers a Flow
For Evaluation of Average of daily floors Historic Three -Month
Flow Trigger ¢n_ during; Rolling
Average r w, oFs
January 1 Oat -Mov -Der-
'Fulruary 1 Now- Dec -Jan 260
March 1 DeG,1an -Feb 3,250
April 1 ,,en -Feb -Mar T.700
Ma y 1 Feb- t,ller -A r 7.5Ei.0
Jkine 1 Mar -A r Ma 6,854
July 1 Apr- May-�ue
August 1 Ma - Jun -Jul 4,200
Septern lr 1 JUn-Jul-A.Lig 3,600
October 1 Jul-Aug-sep 3,200
November 1 ,4ug- ep-Orl 3,300
December 1 yep -W -Nov 3,554
7 Ful. Pon-a Elevation —Also referred to as "Full Pond ". this .s the elevation of a resenra,r
(mdasured in fee`., U 30 S datum [NGVD 192 91) the; carrespancs to the point at which water
would first begin ,a sRil froin each reservoir s darn if the respective Licensee took no autior..
This elevation rnrespondsto'he lowest pc�int alo igthe top -Df the Spillway (inctudtng
flashboards) for mervairs with out flood gPLtes; and to the lowest poii>•t @long the top of the
18
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flood gales for reservoirs that have flaad gates. The full Pond Elevation for ViCh pro,ects'
reservoirs s listed in cable 2
Table 2. Full Pond Elevations
S. Normal Reservoir Operating Range-The band of reservair vrater slevations within tivnich
the Licensees normally attempt to maintain a gvan reservoir on a givar day. Each reservoir
has its own specific Normal Reservoi - Operating Range, bounded by Full Pop Elevation
and Normal Minimum E:evation. If net inflows to the reservoir are within a reasona Die
toleranr_e of the average or expected amounts, project equipment is operating properly, and
if rndintendn(� cr emergenry aperatiorL plans have riot been implernentec, reserycir water
elt Ovation excursion$ 4ot6rdo of tree Normal 4�eseruo r Operating Flange should rut QcCur
The new FERC license for the Yadkin Project include6 operating iwvoe that establish tho
Normal Rcsorvoir Operating Range for oari Yadkin PtojvIt reservoir.
9. Normal Mini nurn Elavation iNMEj -The elevation d' d reservoir (rreasured in feet, USGS
datum [NGVD 19291) that defines the t lorr, a` :he rese+voir'b Normal Op�-ca -.zng Mango for
a given day of the year. NME for each Df the projects: reservoirs is I ;;tad in Takla 3
Table 3. Normal Minimum Elevations (feet USGS datum - NGVD IM)
Mouth
High
Ronk
Full Pond Elevation
Reservoir
Tillery
(feet, USGS datum - NGVD 1929)
Hip Rock
332.8 278.2
328.8 273.2
523.9
Tuckertown
613.9
51 &.9
transition
6199
504.7
Narrows
328.8
329 6
5D9.8
Falls
6617 5W 8
561 + 504 8
332.8 - --
Tillery
172.1
172'l
1.72 1 -_
172.1
112.1
278.2
Plewett Falls
561.7 504 8
1781
S. Normal Reservoir Operating Range-The band of reservair vrater slevations within tivnich
the Licensees normally attempt to maintain a gvan reservoir on a givar day. Each reservoir
has its own specific Normal Reservoi - Operating Range, bounded by Full Pop Elevation
and Normal Minimum E:evation. If net inflows to the reservoir are within a reasona Die
toleranr_e of the average or expected amounts, project equipment is operating properly, and
if rndintendn(� cr emergenry aperatiorL plans have riot been implernentec, reserycir water
elt Ovation excursion$ 4ot6rdo of tree Normal 4�eseruo r Operating Flange should rut QcCur
The new FERC license for the Yadkin Project include6 operating iwvoe that establish tho
Normal Rcsorvoir Operating Range for oari Yadkin PtojvIt reservoir.
9. Normal Mini nurn Elavation iNMEj -The elevation d' d reservoir (rreasured in feet, USGS
datum [NGVD 19291) that defines the t lorr, a` :he rese+voir'b Normal Op�-ca -.zng Mango for
a given day of the year. NME for each Df the projects: reservoirs is I ;;tad in Takla 3
Table 3. Normal Minimum Elevations (feet USGS datum - NGVD IM)
Mouth
High
Ronk
Tucker- Narrows
town
564.7 59.8
561 7 504 6
Falls
Tillery
Slowett
Falls
Full Pond 523.9
332.8 278.2
328.8 273.2
178.1
January 1
February 1 _
March 1
April 1
613.9
51 &.9
transition
6199
172.1
5617 544.8
328.8
329 6
273.2
275.7
172.1
172.1
6617 5W 8
561 + 504 8
328.13
275.7
275.7
172.1
172'l
1.72 1 -_
172.1
112.1
May i _ 619.9
Jinn 1 _ 610.9
July 1 619.9
Au i.fit 1 6199
561.7 5D?1 8
561.7 504 8
328.9
328.8
275.7
275.7
5617
561.7_
5$1
'5048
5048
504 8
328.8
2 rb. f
Sgterrber 1
Oct obe -1
619.9
619.9
328.8
328.8
V8 �5
275.7
275.7_
275.7
172.1
V2.1
172.1 --
172.1
172.1
561.7
561.7
561.7
6048
5D4 8
_
November 1 transition
Demmber 1 -1 b 613.9
5D4 8
1328.8 27$ 7
1328.8 273.2
a Public Wale rSyst4rn is
water to the public having
December 16 -31 $1 rJ
"0. Public Watec9y t in -For the
or privately owned water systorn
561 _ 7 _
504 8
purposes of this LIP,
that supplies potable
any PU01cly
an
19
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instaManeo.is withdrawal capacity oFcre million gallons per dap Dr more, and witharavrs
frarn storage in the projects reservoirs.
11. Non - Public Wator User — For the purposes of this LIP. d Non - Public Water User is any
publicly oe pivately awned water withdrawer that wikhdraws water tor uses other than
supplying getable water to the public, having an in 50rltonen Js withdrawal capacity of one
million gallons per day or more that wilhd ram from storage in the projects' reservoirs.
12 J S. DroLght Monk. — A synthesis Of multiple indces, outlooks, and news awuu•its
(published by the U. S. Department of AgRCUlturej khal represent a consensus of federal and
acadornio scientists conceming the drought status of all parts of the United Stakes. Typical y,
the U. G. Drought Monitor indicates intensi'y or draught as DO Abnormally Dry. D1-
Mrjderate, D2- Severe, 03- Extreme a -id Gil- Exceptional. The current U S. Drought Monitor
and explanator{ material can be found at httZ:JAVAw. drain l-it.A.edufdrnlmanitor. him 1.
13 U.S. Drought Mon for Three- Mionkh Nvmeric A� age — If the U.S. Drought Ataniior has a
designation ranging from DO ,c Da m of the last day of a month for e y par. of the Yadkin -
Pee Dee River Basin that draln9 to the Blewott Fails development, the basir will ce
assigned a numeric value for that month. The numerio value will equal the highest U.S
Droughl Mcrilcr designatiDn (e.g 00 -0: DI =1, U2�2, U3 =3 and D4=4) for any park of the
Yadkir -Pee Dee River F32sin draining to Blewett Falls development as Df the last day of the
month. A normal 4onditicn in the basin, defined 99 #hn absence of a drought desigrlakion, will
be assigned a nurreric vn uc of negative ane ( 1). A. rolling average of the numO.Lrir values of
the current month and previous two manure will I>ei calculated by APO at the end of the
month and designated as the U.S. DroughL Monitor Tb ree-Mo nth NumerioAvEaragc for
purposem or .his LIP.
14. Critical Reservoir Wa!ar Elevation — The refia.nroir water elevation (measured in feat.
USGS datum [KJOVD 1 929]) below which a Public }Plater System intake. Nan - Public Water
Users intake, or hydropower plant laoakad on the reservoir cannot operate under normal
aonditiuns. Crib caI Reservoir Water Elevations are defined in Table 4.
Table 4. Critical Reservoir Water 10"44i an
Critical Reservoir
Rasar ck Wafer Elevation TYPe
measured at the dim
(feet USGS Datum - NGV01929)
High Rock 5-999 04 ft below full pool) Hydropower Produotiun
Tuckertowir 580.7 (4 ft below to II pool) _ Public W,31er Supply
Narrows 4868 f23 ft belgN ful pool) Public ~Aster Supply —
Falls 322.8 (10 fk below ful I I ) =l I drapower Production
Tillerl 2138.2 i 10 ft below full coal Puclic Water Supply
81owatt Falls 168 t'0.1 ft belowfull pool) P.iblic Water Supplyf Hydropowef
Producthan
16. CJtio I Fe Low— The Rows from the projects #hal are necessary to prew9i7t long -term or
irrcversible damage to aquatic communities consismnt wit-i the refinurce management goals
Scud ofz�ectNes for the afFiticted stream reAr Kes and necessary to provide some basic level of
water quality rnairi#enance in affected river roaches, For the purposes of this LIP. t -le Critia2
Flows are defined as Follows:
20
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+ Falls Development — the Critical Flow f om the Falls Development is equal is t (0
Js measured on a daily auerage basis.
Tillery Developrment — the Critical Flow from the Tillery Development is the same as
required minimum instream Pow as defined in the new FERC iioense for Yadkin Pee -
Dee River Hydroelectric Projec.
+ Blewett Falls Development —tne Critical Flow from the BFewett Falls Development is
023 c�s rmcasurod an a continious basis.
10. Organizational Ablareviaiigns — Organizational abbreviations include Aloaa Power
Oor7anating Inc. (APOI), Progress Energy (PEY, NC Department cf Environment and Natural
ReSOUTCeS (h1GDENR), North Carolina D vision of Water Resources {NGI7WRj, Nor_b
Carclina Division of Water Quality (NCD*Q)_ North Carolina 1ArldI fe Resources
Commission (MF;WRC). South Caro ina Department of Natural Resources (SLUNK). Sou.11
Carolina Department of Health and EnvrorirrrentaI Qontro I (SCDHEC). the United States
Fish @rnd Wild life Service (USFWS), High Rack Lake Association (HRLA), Badirr Lake
Association (DLA), and South Carolina Pee Dee Riser Coalition (SCPDRC).
17. Yadkin -Pee Dee River Basin Dmouclht Manacleneml Advscry Croup (YPD -D MAO) —The
YPD -MIAG s established to facilitate imp4emantation and review of this LIP. Members of
the YPC] -DMAG agree to comply with this LIP. Membership on the YPD -DMAG is open to
one rapres.enWi-de tram each of thetoltawing DManizaticrs:
APGI
* PE
• NCDWR
• NCDlrvQ
+ NCVVRC
• SC:DNR
SCDHEC
USFWS
r Duke Power
• HRLA
BLA
Lake Tillery homeowners repmGsMatign
•
All owners of a Public- Water System intake or a Non - Public, Waver beers Lntake that
witted -aw t•om storage in one of the projects' reservoirs.
The Lkenroer, will share the TesponsibHity to notify NGDUVR of a Law Inflow Conditinn
NGDWR and SCDNR will share respaneibility to coordinate with the YPD -DMAG including
notifying, setting agendas, leading discussi(3ns. and providing calfteeti-ig summaries.
Regardless of the Low Inflow 03ndifian, coordinatior will include a meeting convened
annually by NCDVVR during April to discuss issi.as r(B.Irsvar, to this LIP. Membership in the
YPD -DMAG may be expanded based on a consensus of the momt)-mi5 or at the direction of
FLH0. 1 h NCDWR will maintain an active roster of the Y�, -DMAG, will prepare meeting
summaries of all YPD -DMAG meetings.
1B. Revising this LIP — Durii)g .ne mow FERC license period, the YPD•DMAG wil' hal rnnv ". Lid
by NCDbVR and SCDNR at Ipaol once -eweryfive (5) yea•sto review and, if necessary,
update this LIP. Decisions on medifrcnlinnSto the Licersees' responsibilities undarthis LiP,
21
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if anv, M! be determined by rpnsensusofthe Licensers and the States of North Carolina
and SOLlth Carclir« (fipecifically NCDWR, NCDWQ. SC DNR. S DHEC) after consultabon
With other rnerngers c -f the YPD- DIa1AG. Proposed moddiration to the Licensees'
re5ponsibilities-will be submitted to DVVQ for mviewan,- aporaval as necessary
MvdifiCations to the responsibilities of other rnem bars Snot the FE RC licensee5j of the YPD -
DMAQ under this LIP, if any, will be Ceterrni nod by cansensus of those members after
cnnsuliation with the Licensees. Appioved modifications will be ircorpbrdtC4 through
rauisian ofth.s LIP. The YPD- []MAiT may appoint an ad noo cum -nittee to Consider issues
rolovant to this LIP. An i5ewe such as the substitution of a reg ion ol drought man ito�For the
U.S. Drought Monitor, if developed in the future, or proportional drawdown of storage
reservoirs during LIP rtoge$ are examples of items :hat may be considered.
19. Cor sensus — The .inanimous support of al I Parrs, of at least no opposition from any
Party
20. Water lrVithdrawel Data Collection and Repartrrr4 —The 3wrers of all Wat,e• intokps
impacted by this LIP are to cam ply with water osa reporting requirements of the appropriate
State Agencies. The YPD -DrAAG can regUest afid should reoeive •eleWnitwateruse
inforrri ill inn from the a ppropriate state 8gency o r d rectly from the owners of indMdua'
imakes.
2' Drought Response Plan Updates — All Public Water Supply System owners and Non-
public Water Users subject to this LIP will review and update their drought response plans,
or develop a plan if they do not have one, to ensure oompliancc acid coordtnativri with this
LIP, including the authority to erforce the pruvisions outlined herein. Nothing in th is LIP is
intended to prevent Public Water ;System owners or Nan- Publiv Water l.'ser5 fwi taking
mare rastriative actions or from complying with any applicable law or regulation.
22. Relationship Between 1h is LIP and Mai rtend:1 C;e and Em emency Plans — }Maintenance and
emergency plans crutliI)a the general apprvoch the Ucersees will take under certain
maintenance, ernpr9a -icy, equ'pment fail u re and other situatlonsta Continue practical and
safe oz�eratiorl of the projects :a mAiniain operations consistenl with the nee FERC license
ppnditions to the maxi -num axtant possible: and to communicate with resourrP agpndas and
the affected parties. Under these plans, temporary inodifica'ionsto required Minimum
Irslream Flow releMes, and the NotrnaI Reservoir Operating Ranges are allowed. Lowering
projects" rtiivoi' water elevations caused by situations addre�.sec under maintenerice and
emergency plans wi11 not iruakp implemenation of this LIP. Also, if this LIP has dl ready
been implemented a: the time that a situation Cowered by these plans is initiated. the
Lirnnscc nay suspend irnplementation of this LIP until the maintet7anre or amergency
situation has been eliminated. Notifioa #ion will be provided by the Licensees to the Mate
Agencies as soarl as practcable.
PROCEDURE
A Law Inflow Wxch a, Law Inflow Condit on, as speorfically tlefinod below, will he triggered by
the oambination of conditicrs defined in T2blc 3. This LIP Y611 be implemented at Slags 0 and, if
Me combination +,f Conditions becomes more severe, the 5ti 9 will increase in ore stage
increments. The Licensees and other water users will follow the proced.i re set forth in this
section regarding communications and adjustments to f:ows and other water demands.
22
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Table 5_ Summary of LIP Triggers
High Rork
Stage . Rose rvalr Elevation
< Nh1E minus Q � f I and
0 1 � WE
I I <NME minus I €t
1 <NME minus 2 )
3 <NME minus 3 ft
X112 of . VMI minus
d Crtical Reservoir
Wal.ei Elvvdtiod
US Drought
W-nnitar Three -
Month Numeric
Average
ary 1 or
OR
stream Gage Th ree-
Month Rolling
Average
as a parcent of the
Historical Average
and
>0
Dr I 48;0
either
—
>1
ar rt41�6
and
either
and }2 or35°r6
either
<30 °G
and
n3 or
either
and >d
or
<30 %
either
I
The LIP Flaws set forth in Table E wil be snit ated an a monthly basis and are designed to
equitably al ocati?� the impacts of reducec water availability in accordance with the goal Df this
LIP. Initiation of this LIP will be Lased an analysis of the trigger oariditions on the first day of
each month. The High Rock Reservair water elevation as of midnight between the laid day ❑f
the previous month and the first day attl -.e current Mvr�h will Do u5ee in COMbinahbn wii7 the
U.S. Draught Monitor Three -Month Nurnorii; Average and the Strearr Gage Threl�-Mo .9th
R -oiling Average Flow to determi-le the need to declare a Low Inflow Watch or change the stage
pf Low Inflow Goncitions.
23
,

Table S. LIP FIow91' I. rfs
High Rock Falls? Blewatt Falls : ?:
g imun slow to (daily average flow target} {contirll.aus flow target".)
maximum flovrta etl
Feb 1- May Jun 1- Feb 1- May Jun t - Feb 1 - May Jun I-
Mqy 15 10-31 Jan 31 May 1b 16 -31 Jan 31 1 May 1 16-31 Jan 31
0 2000 1500 1040 2000 1500 1GOD 2440 1840 1200
1 1454 1170 900 1460 1170 930 1750 14D0 1480
2 1080 950 834 1080 950 W 1340 1.150 1000
3 770 1 770 770 I 77D 770_.1 770 926 9415 925_
4 Additional measures may be delorinined by oansensus of the Li :e -lsees and State
A ancies. NCDWO npprmat ❑f any additional measures will be required.
Consistent with the goal of this LIP to Conserve w9ver while maiM;9inl ig
downstream flows, projects will be operatad to achieve the target f aws to the
extent practicable as a first priority arrd to supD.emert inflow, equitably from
the. ;to rage reservoirs as a second priority.
' I n LIP flow values shown in the table abDve reflect flour targets. These va ues
cannot be met exactly aS shown and will likely vary slightly an a real time t»Fis
from the values shown Dore. It is expected that the variances from the larger.
flaws will be minimal. In Stages 0 -2 he releases from Blewett Falls will be
within 5`7b of tfke target as measured at the tJSGS Rockingham gage. In stages
3-4 the Teteafies from Blewett Falls wd 149 between 900 -950 cf, a€ measured
at lone USGS R&ckingham gage.
Local inflows to Blewett Frl'e Reservoir may be large even curing ex:epded
Im inflow conditions. If at eny time dudng the implementation o` the L1 F, IpGal
inflows to Blewett Fal-s Resarroirare large enough to fill Blewett Falls
Reservoir to full pond. Iho Downstream Licensee may tern porar-ly kicreasc
Blewett Falls generation to avoid spill.
Stage 0 - Low Inflow Watch:
Tn;? Licensees will moniloi High bock Reservvi- winter elevations, the U . Drought Monitor end
the designated stream gages and will declare d Stage 0 Love Inflow Watch (cr kne month if the
following condition, are present on the first day of the month
• If the Itigh Rock Reservoir water elevation Is Del ow the NM minus 0.5 ft under a r y
ir,0aw or drought ronditibn.
OR
• The High flock Reservoir wa-ar elevation 15 below its NM E.
AND EITHER
OR
■ TheU. S. DroughtMonitor7hipr-- McrthN-imerioAveragefortheYadkin -Pee
Dee River B$sin draining to Blewe1t Falls Developrnort is greater I-ar) or equal to
Zero.
24
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■ The Stream Gage Thee -Month Rolling Average Flow for the monitored strearn
gages is less than 44N of tho I historic Steam Gage Tnree -Montt RpNing
Avprace Flaw.
When a Stage D Low Inflow Watch is declared=
1 The Licensees will -notify via crnail the MCD'ArR of a Stage G Low Inflow Watch as soon as
practtaWe but np later than three business days af.er the deelnration.
2 The N('DWR will activate the YPD -DMAG and initiate monthly n'eeurQo or w4nf$rence calls
to be held on the Monday before the se�cr-� Tuesday. Monthly discussions will.
a R,2view provisions of this LIP.
In. C;arify communisation channels between the YPD -DMAG rnombcrs.
c. Review hydrological status of the basin.
d. Review the roles of ,3nrh Yimn -DMACS merrber and discuss their plans For responding if
an elewatad Law Inflow Condition is declared.
e. Review information rcport,ng ay YPD DIVIAG members, including a sto rage :h istory and
forecast from the Licensees, a water use history and foreuaet from each wafer uscr on
the YPD•DMAG. and stare -wide drought responss status (including, but nct limited to,
impact to water quality, fisheries. wilgldA, ate, ) �rnm the member agencies.
t. Public canrnunication',
'Strife 1 - Lour Inflow CondItion:
The Licensees wvi1I monitor HEgh Rook Re erwoir water elevations, the U-S. Brought Monitor and
the desirgnatpcl mrsa;n gage and will doe are a Stage 1 Low Inflow Con dition fcrthe month if
thL fallowing cc�nditions are present or the first of the rronth:
The prior month LIP condition was Stage 0;
AND
The High Rack Reserver water elevation is more than 1 ft below the NME;
AND EITHER
The U S. Brought Mr3minr Thrc�P-Month N- LjmeiicAverage furthe Yadkin -Pee
Dee River Basir drain ng to Blewett Falls Develoomoni is greater than or equal to
1.
OR
■ The Strearn Gage Three- ruionth Rolling Average Flaw for the mor4ored stream
gages i9 1e55 than 41% of the Historic Stream Cage Three -Month Rolling
Average Flow.
When a Stage 7 Law Inflow Condition is declared;
The Licensees •quill:
25
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a Notify NC DWR of declaration of a Stage t LQw Inflow Condition via email as Boor, W
practicable but no later than two business days after the dedEvation
b. Impternerit LIP Flows as detailed in Table 6 for each project by the seVerlth day of the
month in which a Stage 1 Lour Inflow Condition is declared. To meet the LIP Flows for
laga 1.
APGI will supplement Hroject inflows by drawing first from Nnrrrsws Reservoir .inti
the Narrows Reservoir dr2wdown below its N M E matCheS the High Flock Reservoir
dravrdawn below its NME at tho time that the Stage " Low Inflow Condltior is
declared.
APO wdt supplement Project inflows by drawing from High RorK and Narrows
reservoirs apprardmately equally on a foot- per -foot basis below the Normal Minim-.im
Eevation f.NME).
PEwill supplement Project innaws by drawingfrorn either Tillery or 6lewet. Falls as
required
c. U pdate their reBpoctivewobsites as noted in Key Definitions, Facts and Asswntptions Nc.
4.
d. Provide Public Alater Systom ,ntake ow iem and Nor - Public Water USer'S with weekly
updates on ruber4nir water elevaticrs and inflow of water into the prcjects' reservoirs.
2. if they -i3ve not alrearly do re sa. NGDWR will tiooroinate with SCDNR to tonduct monthly
meetings or conference calls to be held c the Monday before the second Tuesday. Monthly
discussions will
a. Review prov15iOnS of this LIP
b. Clarify comminit;0p11 channels between theYPID -DPAPG membevs.
c. Review hydrological status of the basir.
d. Review the roles of each 'Y PD-01VIAG member and discubb IN& plans for responding if
an elevated Low Inflow Condition is declared.
e. Review information reporting by YPD -DMAG members, including a stomp history and
rorecast from the Licensees, a water use hiutoq and forecast from each - ,%,ater user on
.be YPD -DMAG, and state -wide drought response statue (iru lvding, but not !imdad to,
.mpact to water quality. rlshe. rips. wildlife. etc.) from the mernberagencies
I. Public ccmmunicatio -ts
3. Gwrers of Pudlic Water Systern intakes will complete the following activInps within 14 days
after a Stage 1 Low Inflow Cor7di #ion is declared:
a. Notify ttleir water cl.stamers of the low inflow condition through public outreach and
communication efforts.
b. ReqLCst that _heir water customers irr.plement volurAary wvater use restrictons, i-1
accordance with their drought response plans. Atthis stage, the goal is to reduu -water
withdrawals by approxi Mato fy 5% from the amount that would otherwise be expected.
Thane restrictions may include:
■ Reduvkivn of LKwr. and landscape irrigation to no -nore than two days per week (i.e.
residential, multi - family, parka. stre€Ascnpes. schools, etc).
26
A -29

Reduction of residential vehicle washiq
a Provide a status updalP ;ci the YPD•DMAC on actual "terwtthdmwal trends anp
discuss plans for mowing to mancatory restrictions, if #hey are required.
4. Nan - Public Water Users on the YPD -DMAG will complete the %Ilowirig activities within 14
days aRera Stage 1 Low Inflow Condition is declared:
a Not'ufv their emplcyees and; orcusbmersofihel (;wuuzflowcondidDn.
b. request that their empinyees and customers -conserve water through reduction of water
u p. P_IPGtric power consumption. and ether means. and
Instdute rn -house conserva,,ibn consistent with thoir drought management plan, and
minimize Consumptive uses -a the extent feasible.
Ste a 2— Low Inflow Condition;
The Licensees will rronitar High Rock RPServalr water elevations, the U.S. Drought Monitor and
the- iesignateo simn n pages and will nectar& o Stage 2 Loxv InflYN Conditiion for 'he month if
tME? following ::o-1dit ons are present on the flat of the month:
* The 0 or m ankh LI P condition was Stage 1;
AND
■ The High Rock Reservoi r water elevation is more than 2 ft below the NM E.
AND EITHER
* The U.S_ Drought falanitor Three- Ma'Ith Numeric Average Far the Yadkin -Poe
Dee River Basin draining to Blowett Falls DeVeloprnent iS greaterthan or
eelual tD 2.
OR
The Stream Cage Three. Mori th Ro Ii Average Flpw for the monitored
stream oagas is less than 35% of the Historic Stream [3age Th rea -Month
Rolling Average Flnw
Whan a Stage 2 Lew Inflow Condition Is devlared;
1. The Licensees will:
a. Nolify NCOVVR of a dea ration of Stage 2 Low Inflow Condiripn via email as soon as
practi0able but no later than two busdnpsfi (lays after the declaration.
b. Impl&rnent LIP Flcws as detailed in Table 6 fo- each project by the seventh day o- rhea
month in which a S;age2 Low In`low Condition is drolared. To 17eet the LIP Flowsfor
Stage:
27
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■ APGI will supplement ProjeJ inflows by drawing From High Rook and Narrows
reservoirs approximately equal y oii a foot - per -foot basis.
• F'L wil I suppl -9menl Project inflows by drawing fmm either Til levy or Ble•ruett Fall s as
requires.
c. Upc ate their respeoti a weasites as noted in Key -Definitions, Facts and Assumpticr,s No.
4.
d. Praalde Public -Wate' Syslem intake ovrners and Non - Public Water Users wdh uD:Wes
twice peF week on reservoir water elevalians 8irtri inflcw of water into the systern
e. Continue participation in month lyor n ore frequent menirng orconfierence calls of thp.
YPD -DMA
2_ NCDWR ml' coordinate with SCDNR to conduct monthly Y PD- DNIAG meetings or
eon°erence calls to be head on the Monday before the second Tuesday. Monthly discussions
will:
a_ Review Frovisions of this LIP.
b_ Clarify C4mrnuinication channels between the YPD -DMAG members
c. Review hydrological status of Lhe Wmin
d. Review the roles of east-: YPD -OMAG mom ber and disouus their plans for responding if
an 91svated Laa Inflow Condition is declared.
. Review information reporting by YPD -DMAG members, inn iding a storage history and
fomeastfrom the Licensees. a water use history alid Forecastfrom each water useron
the YPD- IDMAG, and state -wide draught tespon status (including, but not limited to,
impact to water -quelity, fisheries, wildlife, eto.) frorn the member agencies.
f Public communic4lions.
a Owners of Public Naiei Systen intakes will complete the following aotivities with n 14 days
after the Stage 2 1 ow Inflow Condition is declared.
a. No, ify their water customers of the cont nuAd law inflow condition and! movement tc more
stringent rnandalory water use restrictions through public nuueach and communication
efforts.
I.). Require that their water custarners implement mandatory water use - e7,trii tions, in
accordance with their drought response ptana. At this stage, the gee is to reduce water
,withdrawals by appruxirnatgly 10`/. from the amount that would POOrwise be expected.
These restrictions may include:
■ Limiting lawn -a nd landscape irrgat,Qn Lo no mcre tnFlri nk)2L day per week {i e.
residential, multi - family. parks, streetsoapes, schools etc).
■ Elim!nat.ng residential veh cle washing.
■ Urniting public building, sidewalk, and strut washing activities except as required for
safety a idror to maintain regulatory oomplion c1g.
1 inviting const•uotioai uses of water such as dust control.
28
A -31

Lin ntiiig flushirry Arid hydiarit tebt+nrrd piu[irarny exuept [o mairs[ain water qualdy vi
other epeoal cirr:umstanr.2s
Elimirating the filling of new swimming pools.
■ Enfprre mandatory water use restrictions through the assessment of penalties.
■ En -courage indu Stria ls -ria lufaCtunng process chargesthat reduce water
oon5umptian.
Provide a status update t3 the YPD -DMAG on a�tual water withdrawal trends
4. Non - Public Lvater User, on thE? YPD -DMAG %v IC complete the f(Acvring activi'ies within 14
days eflcrt7e Stage 2 Low Inflow Condition is declared -
a. Notify their einplcyees andlur custurners Df the ow inflow condition through public
outn:ach and communicatian efforts.
t. Request that thei• employees and "5tOrrer5 conserve wa-er through reduction of water
use, electric power consurrptior,, and other rreerl5
c. Institute it -louse conservation conssislen[ witli [heir required d-ought management plans
and minimize con4umptiWe uses to the extent fpnsihle
5tape 3 - Low Inflow Condition:
The Licensees will monitor High Roc* Reservoir water elevations, the U.S. Drought Monitor and
the designated strearn gages a n j will declai a Stage 3 Low Inflow Condition for the month if
the following conditions are present on the first of the mbrTth:
■ The pricrrnonth LIP conditionwas Stage 2:
AND
■ I he High Rock Reservoir=ater elavation is more than 3 ft below the NME.
AND EITHER
r The U.S. Drought Monitor Thr —np- Month Numeric Average for the Yadkin -PrsLh uee HiUe•
Fla ,sin draining to Ble%vett Falls Development is greatertran a- equalto 3.
OR
■ The Stream Gage Three -Month Rolling Average P1 01N for the monibred stream
gages is less Lnan 30% of fhe Historic Stream Gage Three -Month Rolling g,rerago
Flow
When a Stage 3 Low Inflow Condition IS declared:
1. The Licensees will:
29
A-32

a. Notify NGDWR of a declaration of Stage 3 Law Inflow Condition via email as soon as
practicable but no later than 48 hours after the cedaretion.
b Implement LIP FIDws to designated Critical Flcws as detailed in Table 6 for each project
ty the seventh day of the month it which a Stage 3 Low Inflow Condition is ded Ared. To
mom the Critical F ows:
• f%PGI will suppleMont Project irfHcws by drawing from High Rack end Narrows
n:ser,roirs apprcWnxely equally on a ;Dot- per-foot basis.
+ PE wll 9upplemeni Project inflowb by drawing from either Ti'lery or Blewekt Falls
as required.
c. Upcate tneir respective tiwcbs'tes as noted in Key Definitions. Facts, and Assumptions
Nc. 4.
d Prm ide Public Water Cystern irtake ovrnem and Non - Public Water kAer's ,a&. bi- weekly
(twice each creek) updates an reservoir water elevations and inDi;w a` water into the
system.
e. Continue panoipation in monthly or more frequent meeting cr Confe. rence calls of the
YPD- DM,4G.
2. NDDWR will coordinate with CDDNR to cc; ncuot rnonthly YPD -DMA a neetings or
confemrce calls to be held on the Monday before t7e second Tuesday. Monthly diwursions
wd I:
a. Review provisions of this LIP.
b. Clarify eornirn i nicaticn channels between tie YPD -DMAG memhers
c. Review hydrological status of the basin.
d. Review the roles of each YPD -DMAG rnernh er and discuss their plans for respond ng if
a7 elevated Lour Inikow Condition is declared.
e. Review inform Fhtlon reporting by YPD -DMAG members, including a storage history and
forecast from True LiaOnsr3es. a wa`Pr u52 history and foreUasl �rom each water user on
the YPD -DMAG. and statewide draught respanss 6'nfus {indudirg. but not limited to.
impart to water quality, fi6hi§rio&: wildlife. etc.} from the member agencies.
f. Pub:ic oommunioationS.
3. Ovwriors of Public Water $yslem intakes will complete the fallaw.ng acJAies within 14 days
afkprthe Stage 3 Low lriflcw Condition is declared:
a. Notify their water Customers of the wntinued low inflow Condition and mowemont to
emergency grater use restrictions through public cutreaaCh and conimunicatior, e`forts. At
Ns stage, the goal is to reduce water Usage by approximately 20% from the amount that
would otherwise be expected.
b. Re!Wiot all oaitcoor water use.
c. Implementemerge-icy water use restrickioris in acco rdance with their dtought response
plans, including enformment of these fertrictiotis and assossmerd of penalties.
J. Prioritize and meek mth their commerc ial and industral larga water customers and meet
1� discuss strateg es for water reduction measures inGUding devetapme. nt of an activity
schedule and contingency plans.
e. Pri;.,para to mplernerr, emergency plans to respond k� water outageu.
30
A -33

4. Non-Public Users cr the YPD -DMAG will complete the following ac6vitieswi-hin 14
days after Stage Low Irflow CojiditiDn is declared:
a Continue informing their custom -ers o= the low inf low conditionthrorigI public outreach
ar)d carnminication efforts.
b. Request that their customers conserve water through red uctior. or water use, electric
power omreumptian, and other rreans.
Stage 4 Low Inflow Condition:
The Licensees will monitor reservoir alevstianb. the U.S. Droughl Monitor and the desigrated
stream gages and w 5 declare a Stage 4 Low Inflow Condition for the month if the following
conditions are present on the first of the month:
AND
+ The pnor month LIP condition was Stage 3:
+ The High Rock Reservoir water a evation is Irdss thsi� 600.9 tt US GS (November I
thrcwgh March 11 or less than 609.9 ft USGS,;April t through Oonhnr 1) '
AND EITNLR
0R
+ The U.S. drought Monitor Three -Month Numgri� Average for the Yadkin -Pee
Dee River Basin draining to Blewell Falh� Development is greaser than or equal to
4
+ The Steam Gage ThreE­ Mem�[h Rulliriq Average Flow far the monitored stream
gages is less than 30% ofthp Hifitofir. fitream Gage Three, Month Rolling
Average low.
When a Stage 4 Low Inflow Condli"n it declared:
1. The ticensees will notify NCDWR via email as soon as practicable but no late• ttiaii 4B hc,a - s
after i he declaration.
2. NGD'P1R w 1 rp.qi,e9t a meeting of the YAD -DMAG within f days after the decla.,Aon of the
Stage 4 Law Inflow Condition fir diseussion to deterrnine rf there are any add ion al
measures that can be irnplamigr7ted tQ-
a. R °duce water withdrawals, redum water releases from the projeJs or use nditiuna
resermir storeigewithCLt ore -atirIg mOresevere regional prot:tem €.
' 1-0ss tha-1 c -le half to dls:ence Detn+cen the NME a -ic ih° Critical Reser, -oi, wat5i Eleuatlan
31
A -34

b. Work tpgether is deve op n ans and imp[ement any adeitionaI measuras identified
AMVP
C Conrnunicaie conditions to the public.
f dditiDnal rneaswea may be deterrninod by consenSLS of the L cenSees arid State Agencies
with NGDVVQ approval as necessary.
Recovery from LIP Stages
Reooyery from this LIP will De triggered by any of the three following axicilions:
■ Coadii on 1: All three triggers associated wth a Icwer numbered LIP Stage are met.
OR
Condition 2: High Rork Ro&ervoir water elevaticrs relim to at orabove the NME
PLUS 2.5 ft
OR
+ Condition 3: High Rock Reservoir water elewat ions return to at or above the t~ ME for
2 consecutive iveek5
Witiexr any of these three conditions occurs-.
The Licensees will take the Fallowing aztion-
a. Condition 1: The LIP recovery will be a general revemal of the staged approach
described above
b. Condition 2: The LIP will be disrantirrued.
c Condition 3: The LIP will be discontinued.
7. The Licensees will notify the WMAR via email wiftn 3 busirlass days following altalrtirnant
of any of the conditions nwnessary to return to a lower stage of this LIP. Changes to less
restrictive Stages will be made:
a. Condition 1. on the first of each monln if a slow recovery is Lndicated; or
b. Condition 2. inlinddiately if High Rack Reservoir elevations are at or abov" the N M E
PLUS 2.5 ft
C Condition 3: immediately iFHigh Rock Reservoir elevations are atord17ave the NMEfo•2
canserutive weeks.
3 The Licoansees will update their respective webs.tes as noted iri Ke} definitions, Facts and
Assumptiom No. 4
32
Hevimm ryrogress E rixgy tart ficAc�1 2403 -014', vur 7 EP.Whento, J(30 mad l
A -35

Alsn, this spprmrsl to proceed with your proposed impaets or to conduct impeets Lo wAlors HS
dcpietcd in your applkaticm shall expire upon expirstinu of the 404 or CAM Permit.
Irthis Certification is unaoccptabI;, O )"3, }'qu hyyp the I'iellt to ru] Bldjudi(Alorry L1eHtitg uFwu Milieu
reyuesL Widdrl sixLw (60) dmy:; roll awing rvxiltC oftllis C'cvMcadcu. This ;cquen iuust Ise in the form &f a
'kwiaern petirica Coiltomling lu CLl<1pwr 15013 ul Lhe %: vb Cffrolinx (kmLr'al Slaftnes and tiled with the
Offco of Admiai,%Vive Hear fts. -6714 Mail Seevjce CauL&, R,')kiA, N.C. 2769") -6714. Tf
mudi fic.atians arc madc to an prig ina I C ulifICADD, You had -%e the YigLLI 10 an ft i udic,ilory heurin on thr
rtL�adiJi{:LLiuns upLm urittcn reyucct within sixty (611) dws mllowblg 1cccipt 4l'dLe C'11I9ifiCaLiLM- UnlVs�,
auwLL Q:V I]dtLd2, are n]aLlr_ LhLs CtrtificaLim xhall Lam. final skid binding,
This Lbe i2Lh "y ul Srptembcr 2009
D14- JLSIO� OF WATER QLUALTTY
61ccn FL Sullin I _rcct r
k -' Chcrsiyk-T5l]a i Review Pere: d5.ir, I mg .
I. OV2il Seri - ;femme 4JIrip)l, 40. III r.`alvli[W 2'6 ?u -]6 ?G
2 ?'d7 (.rzI+nxrWjIpaf %I.' uLks 1_SG - FALL iVJL IL)rIh Cx:lllna 2-- N;
PIIOIw: P17- ,J3--L:TB@ 'A'e -C 919 7�1A 699.3: lnterrw- hut" h'n em ara•.uc .a•n�- ci I Lb
Ant —gLm I(II.DOi,nil .'_kIl'umelitvik-Ii_m Imalav:r— SVI.RevjxI&d' 1045 P Air [:.)rn; Cf YrN'r
tij up(:mlina
i }11a?dflli}��f

A -37
Progress Energy
Buchanan Mitigation Lands
1532.9 Acres Donated
Y 17d}11�1
i iMaid}
b%- y
K
;r
a{
N l7q4nw
a urrer�r
V
4
Legend
IL 17 INki1
&4"7"A
Pee Dee Ri,*p
� Buchenery Mil��MiRrS
K �i&M& R7
J finds E.�,t0/6ss
— DOT Rtads
a CA 4E
A -37

4i -ti -y In ll)Walw14 wl lUU
Progress Energy
Almond Mitigation Lands
Peo Doe River
DOT made
A -38

A -39

Progress Energy
Blewrett Falls Mitigation Lands J,-�
y-r
F! .
4
Legend
Restrictive Covenants
-
WT Falls Lake
o nas os e
— T RO�dG
A -40

A -41

A -42

Appendix B
Letter to Mr. John Dorney, N.C. Division of Water Quality
from
Mr. Ken Kennedy, Progress Energy, Hydro Operations
January 25, 2011
Subject:
Proposed Temperature and Dissolved Oxygen Compliance Monitoring
Stations
Yadkin -Pee Dee Hydroelectric Project No. 2206
401 Water Quality Certificate (No. 3730, Mod1) Requirements

Progress Energy
?�,.°n ary 2.5, 2011
lrJl. JU13JL Dio-rnCy
North Carr..Iina Division of 'f ka#er Quali v
401 UversjohL- T'xpress Re;-iew Pc=ittin,� 'Unit
16 ;1) MEil Sarvice C'cnic:
Ralcigb, �C 27699-160
Dear VT. Domoy:
�UBJECT' Proposcd Di&,,oivcd Oxvger. a17d Tempc:attue CnrrlpJrmcz -Nloniu3rirtg Lucations
Vadkin -Pee Dee Hydror.loctric No. 2206
'ql NWatcr Q-jaliC�: C'artifLcate ,; \rs. 37:10: Vod L) RegLdremcnts
Prrrnur on -3he meeting atthe Tillery an4 BlcvL-n : alls 1'TydT0C1 1,'c Drvv1vpnrc`nts on danuat'.
1?�_ 2011. ProPpmss Lne -gy requcsIs LIIAL Lhc N.C. DivisiDn ix—V xcr Quality ANC' j)wQ) revie�ti�
a_,l i:13provc the -3ronosed dissolvad oxygea j.1)U) a. d tempc_xturo cotnjrliarrc: _:r�nirorin
?oc €tion in etu;h power plan-, tai.i�.��Elters. .lie Piopas4d eampliamz Luorutorjn� localions are in
acc�rdanc ��itir the lPr.at ess ]- norg -,`s DO :irilttanc•:7ricnt i'la -s lilmi in its 401 Ll'atrr Quality
Cartificate apno-lkulion to the NC'DWQ' and, 9;1l+xtgvrntly- NC. DWQ 401 V'v:(,,C isxucd an
Sep-rcrikr 30. ?ON -'
As reviewed Dn -sit., 11.orss F'ncrL -L
pr %xi, 4he foJ17 -hT cnmpliancc monitoring locations
fax tlr. Tilleiy and '3L �
cu-kTn Falls 1T }' m(t lcct:is jDeveippm. nRn:
PrDposed DO and Temperature Compliance
HAroeleetric Developm t M-liforing Luca ion
Tiller N.C. llji 2hwuv 7' 1 Bridgo (mid- rhannci)
13leWeLlFalIs Ta_1raL:c, mica- ah�uur:.] dfj3Raxi7MLCJy 800 feet downst :cain i }f
p91.'r cr pant c.Piu.c 2)
The proposed Compliance mor_iloring locations will pmvide long -Icryn ]W.nitrtins, elf DO
4 mentrwjcns and Icniperang-e in the ncxt =Eli(' Fucngr. t,rm of the Pro'c'Lt- The Tillery 1314ni
cOmalianrc loci :inn ix Krpnx:mntek,- 2,000 fee- downhtrcarn at the Tillers Pant kr ilc the
wpLased F314v'ett l'alli; R '-ni(03ing locution is approximauely' 80 fL:c[ Liu WE_,SLr�!um of the power
I etU, ;a Vir. Tad-d 5t. jc%nns. N.C. Divi!;ipn of Water Qua Ry frcm Mr. Ph 11 _uLe�, Pra3Kress Ener21, May 11, 20L;/.
Suoject: '?Ndkin -Pee Dee ?rojr. -1 1 =ERC Vo. 22116 -mo}, Secrion 402 VJdWr C�uali:yCertlil[a:lp-1 A�)plics. ion.
L[ Aux ; hrr. Charles S;uCS. ?repress Energy Tam 0 -.dl Karoly, 4.C. Civislor. of VfaX, C�ual,ty, iEptamopr 3C,
2008. Re' Yodki.i I% Gee Project for Tillery and P ewtL: Falls ReservoIrS. Rucgingham, Mnl'e, Anson,
Rlchro6nd, -nnd MQ-tgorr erp Cauntics, -jWCL -:2110 X117, Version 2.0; redera En -2r6N Rep. atory Curr mission
Prcjert 2206, Apprcvel of tUi Wax, Qua. 1-y €r. :,ifrral an — hiodlfled.
Fr )OD E'n'u5 Cnvliras, -c
n - r...
'd-I ,I r:'r.'
B -1

p ?ant ir, the tailracc (Figares l and E), Bolh proposed cA mplirnce mjnilorinl 10 CL iot,.q are
czmsiszc t with location rcqlllrcaicntS spn:incd ir. the NC DWQ issucd 401 WQC, .
The yrnn;y�,cd lm.8rions a"thc. -k- compliHmT.. m fin ii4 r:n6 N101:rrrA rare Lhe result nl'ex[e -nA %q-- DO
eTn11mm-unt tusting and +natcr quality iM- CAigalirms crrndur wd by Pr Lq- €s Lrtvroy front 2006
to MAI. Rc5ult5 of thnsc studin have b--en l-reviuusly li:ecl wi:U Nu DWQ for rcvic }ti' and
discussrd during urmuO re-view rr=631gS betWec❑ NC 6WQ Lt.LLJ Pco�,eiS ELIMly staff: The
proposed :pu'uions will p --vide fepresernat "ve sanililes tar die DO comecntratiom and
letnperac. %s iii .Nat�,rs from -he power plant tail: ice areas.
Praaress Energy is warkillg xith -he U.S. G%--alagical Suvav to acgvirc t4 mosr tr.rhncil4)&.,lly
feasib "e nio-.dtodne egiiipmieni for each of the respKti }Ve rnorritori„g lrrcatinn5. We a"-Iticipat;:
that the USGS wil: ins-call thz oclripnicnc di ring this yvaT; but r.,aj not havit flit vq- .3ipmm -. Jull ;-
fumcui:�nal until 0,.r May wher ci it interim compliance :iioniroiing seas rn Begins" As an ir"rerim
m 4,re, Frog "ss Forgj '.vi'l 2ontinue to operate its temporary' monitorh- sandcs at the
pcopo -;ed compliance rnanbri ig locations in each tailrace und' the USGS equipnicnt is full,
in;toLlIad and 4unctional. Afer the USGS equipment is hinalled and functional, x c will revicW
the mouito °irg data uiTh the NC D %VQ to detet'mitie t= their Rrr my adji3xtmrntw mrcm mry '41 the
aho3an4;orrplianoe lacatiaus.
Pr4igress Fm rgY nqww that NC T)W r�,v'.ew and appro -e in }4_itine cbe pry -Dscd DO mid
ternperarjre Cnrriplianee monimring ;acatinat,. 13 no ss Enet'gy iv[Jl prarvide t "i% NC I)WQ the
OJ S coordinates for earn of the roanitori: i .ocaaans once apprc v':�d_
Please Corila;x Mr Jahn %.r3trhfirH f414- 7415 - !6141 i• %-ou hHvn any qu6cUiniiR -gar-dira the
proposed complisncc monitoring ..c3cations.
Enc;losum
c; SILO" Bowler —ITRC.
.Ir)hn (''m% afield
Mark' A- Pawlorw3ki —H RC
AWN
7C" e"nnedy.
I h dro 0 oeimoiis Ma.wger

'Yadti.' Pee Oee Rive, Ve,o&,ctric P•o '.ect, : ERC P,o,cc: No. 22C& InveSti, atiGns of r4mur4s to Eil'arir?
J ssolveo Oxvr;er EimcE- .trati :m ii the Tailraters a.' the Tillery and Baw.tt 'ails Hwd•aelectric
Oevelaommts. PHASEI: TurbineV=- -tiny. D &MET3,b- H&AssaCeTes.'iPr112607.
Yddain -Pee Dee Rifle• HVdroelecttle 3eoje,L FERC Projim Y0. =N& Inwesugatiors of Measures to Enhance the
Dissolva- Oxygen Concentrations h the Tai.•uaters of the T;IIe•y and B Av,tt :alls HWdraelectrir
Deralopnents. PHASE II: Bvfare Mixing and Compressed Air. DevineTarbell ardAssvciates..une c00$.
wadk n•Pee Dee Rwer Hycroe'ectr:c Pralect. FERC Pro. °c. no. 2746. Inv -estIggloo of roeasures tc 2nhanw
Dissolve,c Csxy2eo Concentrations ii the TM,watirs of the T.IIe'u and Bexreti Falls Hydroelectrii
Developnants. PHASE II.: 2008 A'& aiffuser with Surface hi'xinE. HDR/DTA. lure 2009 -
P-ogreRs Energy. vadkir. -Pea Dee River - lydroalertrit Pro;ert FERL P-Dje t Na. 2205. Rap.i @h, North tarollnr.
Dls�❑lopr. C&ySp,° Fnhan ^pmanl Fm-Id Verlilra im mmhnn: for Ip. - I.Ipry And R;w.d.,ptt Fak Flydrnelpetrlc
Dem-or mints. Phase IV -2009: Baffle pates. aerat'on rinE. par EI rash rack bla:kage and ar f;usg
deploym ert.. an ra ry 2010.
Pfngev Fnergy "adkln -Ppg :�°p Rlvef Aydrnal&n.trc Prnjml FERC Pr:jml No. 770. Raelk, NxTh �Mrnllnt.
Di-;$ glvpfI ^xy ?pn Fnhankpm -n! F'p:d Vpriiirgrim M4pthrs3c fpr -Fp 'illpry anrj R gupkt FaIIS iyrlru?Ip{xri,�
Dewelspments. Phase IV- 2010: ]raft Tube Vemin@, rd.nimurr =Igx Tests, and _ngineerin¢ Eualuatior-.
Deoere.bar MIC.
Pro,V,,*s EnerEv. Continucoa W;+ -er Qua.ity Vcn'turinR -, 1'.e RRF, Jea River aglow the T:I;pr4 and Blewetc Fa 119
Hydrealearit Flanks, may -0ctoba - °, 2W6 -2009 Cecer•.ber 2014.
B -3

rnch)iure 1. Props -ed dissolml orygen and complianas wonitg-nng locatir- nt the
Til.lcry Hidroclectric Y7evelupment for 401 Water Quality CcrlifiLldu
re {luimments is the n -ml. FF RC. license term.
B -4

Fnrluxure 2. Propipsed di.%X1I1 Vt-1l flkyge.n snd comPIiarree monitoring Irrcation at Flee
131evrelt Fxlln Hydrocieclrie De}elipmrnt for 4{}1 NValer QuAty C:errifies�te
rrquiremeuts iu tke ava FE, RC license term.
B -5