NC0005363_Other_20160503

ENKE
GY.
April 28, 2016
Jeffrey O. Poupart
Water Quality Permitting Section Chief
Division of Water Resources
Department of Environmental Quality
State of North Carolina
1617 Mail Service Center
Raleigh, NC 27699-1617
Harry K. Sidens
Senior Vice President
Environmental, Health 8 Safety
526 S Church Street
Mail Code SCUP
Charlotte, NC 28202
[phone]
Subject: March 2, 2016 Insufficiency of Discharge Assessment Plans — Duke Energy Carolinas,
LLC and Duke Energy Progress, LLC
Dear Mr. Poupart:
This responds to your letter of March 2, 2016 to Duke Energy Carolinas, LLC and Duke Energy
Progress, LLC on March 2, 2016 regarding Duke Energy's proposed Discharge Assessment
Plans.
With regard to your letter describing changes in Section 3.2.2 Observation and Sampling:
• The discussion must include a statement noting that jurisdictional determinations regarding
the extent of waters of the United States and their relationship with identified seeps at the
subject facilities will be obtained from the United States Army Corps of Engineers (USA
COE).
Duke Energy does not yet have jurisdictional determinations from the US Army Corps of
Engineers for the relevant areas at all of the twelve sites mentioned in your letter. We submitted
applications for jurisdictional determinations in September, October, and November 2015 and
have since worked with the Corps of Engineers to schedule site visits and provide draft plats for
approval. Nonetheless, the timing of the approved jurisdictional determinations is up to the
Corps and outside of Duke's control. To date, out of these twelve sites, only Buck has an
approved jurisdictional determination, but we do not yet have the signed plats.
We will submit the maps you have requested for each site on a rolling basis, within a reasonable
period after the jurisdictional determinations are complete. In order to address the changes
described in your March 2, 2016 letter, we have added the following text at the start of Section
3.2.2.
Jurisdictional determinations regarding the extent of waters of the United States and
their relationship with identified seeps at the subject facilities will be obtained from the
United States Army Corps of Engineers (USA COE). Until jurisdictional determinations
are finalized by USA COE, preliminary information will be used to evaluate the seeps as
described in the section below.
RECEIVED/NCDEQ/DWR
MAY 0 3 2016
Water Quality
Permitting Section

The second change in Section 3.2.2 described in your letter is as follows.
_ The schedule for water quality sampling of the seeps and related jurisdictional waters must
be more frequent than the semi-annual basis stated in the proposed DAPs. DWR
recommends a monthly monitoring schedule, consistent with the conditions described in the
DAPs' general assessment requirements, for all identified seeps that will continue for twelve
( 12) months. After that time, monitoring may be reduced to a semi-annual basis until such
monitoring becomes a requirement of the NPDES permit.
We do not believe sampling monthly as part of a revised Discharge Assessment Plan is
warranted. For the larger receiving waters, data is available from sampling -associated with
NPDES permits that demonstrates the lack of impact on the larger surface waters of the state.
In addition, we are conducting weekly observations of all AOWs on a dam or dike slope,
sampling any new seeps, and providing the analytical results to DEQ. We recommend the
sampling frequency under the DAPs remain at twice/year with the weekly inspections of dam
slopes for any new seeps with data provided to DEQ. We recommend that we collectively focus
our resources on the completion of all of the NPDES Wastewater Permits for the Duke Energy
sites and implement appropriate sampling frequency for each of the permitted seeps in that
document.
However, in order to address the changes described in your March 2, 2016 letter, we have
added the following text in Section 3.2.2.
In addition to sampling conducted with the semi-annual assessments, additional seep
sampling- will be conducted at locations and at a frequency as determined through
discussions with NC DEQ personnel.
We would like to work with DEQ to achieve alignment of the various (present and future)
documents involving required seep activities including:
• Discharge Assessment Plans
• Discharge Identification Plans
• NPDES Wastewater Permits
• EPA requirements
• Any future legal agreements with either DEQ or EPA
Duke Energy is committed to providing the Department with additional information to facilitate
the issuance of new NPDES Wastewater permits. The issues are complex and require special
consideration, as illustrated by the time elapsed since the permit applications were submitted.
We look forward to working with you further to resolve the issues identified here on a mutually
acceptable schedule.
Sincerely,
Harry Sideris
Senior Vice President
Environmental, Health and Safety

W. H. Weatherspoon Power Plant Ash Basin
Topographic Map and
Discharge Assessment Plan
NPDES Permit NC0005363
April 29, 2016

Contents
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CONTENTS
Paqe
Contents......................................................................................................................................i
Figuresand Tables.....................................................................................................................ii
Section1 -
Introduction..............................................................................................................
1
Section2 -
Site Background.......................................................................................................
3
2.1
Plant Description..................................................................................................3
2.2
Ash Basin Description..........................................................................................3
2.3
Site Geologic/Soil Framework..............................................................................3
2.4
Topographic Map and Identification of Discharges...............................................4
2.4.1 Engineered Drainage System for Earthen Dam........................................5
2.4.2 Non -Engineered Seep Identification.........................................................5
Section 3 -
Discharge Assessment Plan.....................................................................................
6
3.1
Purpose of Assessment.......................................................................................6
3.2
Assessment Procedure........................................................................................6
3.2.1 General Assessment Requirements.........................................................6
3.2.2 Observation and Sampling.......................................................................7
3.2.3 Evaluation................................................................................................9
3.2.4 Assessment Reporting.............................................................................9
Section4 -
References..............................................................................................................10

Duke Energy Progress, LLC I Discharge Assessment Plan W. �♦1 H. Weatherspoon Power Plant Ash Basin J
FIGURES AND TABLES
Figures and Tables
Figure 1 — Site Location Map
Figure 2 — Topographic Map
Table 1 — Seep and Associated Discharge Locations and Descriptions
Table 2 — Laboratory Analytical Methods
Table 3 — Weatherspoon — Example of Surface Water/Seep Monitoring Flow and Analysis
Results Table

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SECTION 1 - INTRODUCTION
Section 1 - Introduction
The purpose of this document is to address the requirements of North Carolina General Statute
(GS)130A-309.210(a) topographic map and (b) Assessment of Discharges from Coal
Combustion Residuals Surface Impoundments to the Surface Waters of the State, as modified
by North Carolina Senate Bill 729, for the W. H. Weatherspoon Power Plant (Weatherspoon
Plant) ash basin operated under National Pollutant Discharge Elimination System (NPDES)
Permit NC0005363.
The following requirements are contained in General Statute (GS) 130A-309.210(a):
(1) The owner of a coal combustion residuals surface impoundment shall identify all
discharges from the impoundment as provided in this subsection. The requirements for
identifying all discharges from an impoundment set out in this subsection are in addition
to any other requirements for identifying discharges applicable to the owners of coal
combustion residuals surface impoundments.
(2) No later than December 31, 2014, the owner of a coal combustion residuals surface
impoundment shall submit a topographic map that identifies the location of all (i)
outfalls from engineered channels designed or improved for the purpose of collecting
water from the toe of the impoundment and (ii) seeps and weeps discharging from the
impoundment that are not captured by engineered channels designed or improved for
the purpose of collecting water from the toe of the impoundment to the Department.
The topographic map shall comply with all of the following:
a. Be at a scale as required by the Department.
b. Specify the latitude and longitude of each toe drain outfall, seep, and weep.
c. Specify whether the discharge from each toe drain outfall, seep, and weep is
continuous or intermittent.
d. Provide an average flow measurement of the discharge from each toe drain outfall,
seep, and weep including a description of the method used to measure average flow.
e. Specify whether the discharge from each toe drain outfall, seep, and weep identified
reaches the surface waters of the State. If the discharge from a toe drain outfall,
seep, or weep reaches the surface waters of the State, the map shall specify the
latitude and longitude of where the discharge reaches the surface waters of the
State.
f. Include any other information related to the topographic map required by the
Department.
The following requirements are contained in General Statute (GS) 130A-309.210(b):
b) Assessment of Discharges from Coal Combustion Residuals Surface Impoundments to
the Surface Waters of the State. The owner of a coal combustion residuals surface

Duke Energy Progress, LLC I Discharge Assessment Plan W.H.�1
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SECTION 1 -INTRODUCTION
impoundment shall conduct an assessment of discharges from the coal combustion
residuals surface impoundment to the surface waters of the State as provided in this
subsection. The requirements for assessment of discharges from the coal combustion
residuals surface impoundment to the surface waters of the State set out in this
subsection are in addition to any other requirements for the assessment of discharges
from coal combustion residuals surface impoundments to surface waters of the State
applicable to the owners of coal combustion residuals surface impoundments.
(1) No later than December 31, 2014, the owner of a coal combustion residuals surface
impoundment shall submit a proposed Discharge Assessment Plan. to the
Department. The Discharge Assessment Plan shall include information sufficient to
allow the Department to determine whether any discharge, including a discharge
from a toe drain outfall, seep, or weep, has reached the surface waters of the State
and has caused a violation of surface water quality standards. The Discharge
Assessment Plan shall include, at a minimum, all of the following:
a. Upstream and downstream sampling locations within all channels that could
potentially carry a discharge.
b. A description of the surface water quality analyses that will be performed.
c. A sampling schedule, including frequency and duration of sampling activities.
d. Reporting requirements.
e. Any other information related to the identification of new discharges required by
the Department.
(2) The Department shall approve the Discharge Assessment Plan if it determines that
the Plan complies with the requirements of this subsection and will be sufficient to
protect public health, safety, and welfare; the environment; and natural resources.
(3) No later than 30 days from the approval of the Discharge Assessment Plan, the
owner shall begin implementation of the Plan in accordance with the Plan's
schedule.
The North Carolina Senate Bill 729 establishes the submittal date of this topographic map and
Discharge Assessment Plan no later than December 31, 2014.
The topographic map, developed to satisfy the requirements of GS1 30A-309.21 0(a), was
utilized as the basis for developing the assessment procedures presented in this plan, required
by GS130A-309.210(b).
2

Duke Energy Progress, LLC I Discharge Assessment Plan FN
y W. H. Weatherspoon Power Plant Ash Basin
SECTION 2 - SITE BACKGROUND
Section 2 - Site Background
2.1 Plant Description
The Weatherspoon Plant is a former coal-fired electricity -generating facility located in Robeson
County, North Carolina, near the city of Lumberton (Figure 1). The location of the Weatherspoon
Plant is shown on Figure 1. The Weatherspoon Plant started operations in 1949. Two additional
units were added in the 1950s. Four oil and natural gas fueled combustion turbines were added
in the 1970s. As of October 2011, all of the coal-fired units were retired. The four oil and natural
gas fueled units continue to operate to meet peak demand. The facility is located southeast of
Lumberton on the east side of North Carolina Highway 72. The topography around the property
generally slopes downward toward the Lumber River.
The Weatherspoon Plant utilizes an approximate 225-acre cooling pond located adjacent to the
Lumber River. The ash basin is located north of the cooling pond, northeast of the plant. The
Weatherspoon Plant NPDES permit (NC005363) authorizes the discharge of recirculated
cooling water, ash sluice water, domestic wastewater, chemical metal cleaning water, and low
volume wastewater including reject water from a reverse osmosis water treatment unit from the
cooling pond via Outfall 001 to the Lumber River under severe weather conditions and cooling
pond maintenance.
2.2 Ash Basin Description
The plant, cooling pond, and ash basin are located on the east side of the Lumber River. The
ash basin is located north of the cooling pond, northeast of the Weatherspoon Plant. The ash
basin consists of approximately 65 acres. The 500-foot compliance boundary circles the ash
basin.
The ash basin is impounded by an earthen dike. Ash generated from coal combustion was
stored on -site in the ash basin. Overflow from the ash basin drains to the northeast corner of the
cooling pond.
2.3 Site Geologic/Soil Framework
Geographically, the Weatherspoon Plant lies within the Coastal Plain Physiographic Province.
The North Carolina Coastal Plain is approximately 90 to 150 miles wide from the Atlantic Ocean
westward to its boundary with the Piedmont province (Winner, Jr. and Coble, 1989). Two natural
J' subdivisions of the Coastal Plain were described by Stuckey (1965): the Tidewater region and
the Inner Coastal Plain. The Weatherspoon Plant is located within the Inner Coastal Plain,
which consists of the gently rolling land surface between the Tidewater region and the Fall Line
(Winner, Jr. and Coble, 1989). The Weatherspoon Plant is located within a subdivision of the
C Inner Coastal Plain that is typified by swampy areas in the flat uplands between major river
systems. The Weatherspoon Plant is located on the east side of the Lumber River.
The Coastal Plain comprises a wedge-shaped sequence of stratified marine and nonmarine
(' sedimentary rocks deposited on crystalline basement. The sedimentary sequences range in age
from recent to lower Cretaceous (Winner, Jr. and Coble, 1989). In this region, units of confined
r
aquifers divided by confining layers overlay the crystalline bedrock. These confined aquifers

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SECTION 2 - SITE BACKGROUND
- consist of laterally continuous silt and clay rich layers. The Lower Cape Fear and Upper Cape
Fear aquifers are depicted as the lower -most marine sediment units in the Robeson County
area (USGS 1989). The Upper Cape Fear aquifer is overlain by a semi -confining unit that
separates the Upper Cape Fear aquifer from the overlying Black Creek aquifer. A semi -
confining unit over the Black Creek aquifer separates the Black Creek aquifer from the overlying
Peedee aquifer. In this region, the semi -confining unit between the Peedee aquifer and the
overlying Yorktown and/or Coastal Plain deposits that comprise the surficial aquifer is
discontinuous.
The surficial aquifer is Quaternary in age and primarily composed of sands with interbedded
silts and clays. The Yorktown Formation is of the Tertiary Era and generally consists of fine-
grained sands, shell material, and bluish gray silts and clays. The contact between the Yorktown
and the underlying Peedee may represent an erosion unconformity. Cretaceous in age, the
Peedee formation generally consists of gray or light brown, silty, fine to very fine grained quartz
sand with traces of glauconite, phosphorite, oyster shells, and pyrite. The Black Creek_
Formation is also considered Cretaceous in age and generally consists of clay, gray to black,
lignitic; contains thin beds and laminae of fine-grained micaceous sand and thick lenses of
cross -bedded sand. Glauconitic, fossiliferous clayey sand lenses are also reported to exist in
the upper part of the Black Creek Formation. The surficial aquifer is the saturated zone that
underlies the land surface and is generally shallow in the region. It is the first aquifer to receive
recharge from precipitation. This recharge water is stored in the surface aquifer as the
groundwater migrates toward local discharge points (lakes, rivers, streams, etc.). A portion of
the groundwater in the surficial aquifer migrates vertically to recharge deeper, confined to semi -
confined aquifers. On average, only a fraction of the surficial aquifer recharge reaches the
deeper aquifers (Giese et al., 1997). This finding is thought to reflect the influence of confining
and semi -confining layers and the substantial amount of time it takes for groundwater to reach
these deeper units.
In the Robeson County part of the North Carolina Coastal Plain, groundwater is obtained from
the surficial, Peedee, Yorktown, and Black Creek aquifers. The Coastal Plain groundwater
system consists of aquifers comprised of permeable sands, gravels, and limestone separated
by confining units of less permeable sediment.
2.4 Topographic Map and Identification of Discharges
A topographic map is presented in Figure 2 to meet the requirements of GS 130A-309.210(a) in
�_' the identification of outfalls from engineered channels, as well as seeps and weeps.
Seepage is the movement of wastewater from the ash basin through the ash basin
embankment, the embankment foundation, the embankment abutments, basin rim, through
residual material in areas adjacent to the ash basin. A seep is defined in this document as an
expression of seepage at the ground surface. A weep is understood to have the same meaning
as a seep.
Indicators of seepage include areas where water is observed on the ground surface and/or
where vegetation suggests the presence of seepage. Seepage can emerge anywhere on the
downstream face, beyond the toe, or on the downstream abutments at elevations below normal

Duke Energy Progress, LLC I Discharge Assessment Plan W.H.��
H. Weatherspoon Power Plant Ash Basin
SECTION 2 - SITE BACKGROUND
pool. Seepage ma va in appearance from a "soft," wet area to a flowing "spring." Seepage
PY vary PP � 9
may show up first as only an area where the vegetation is lusher and darker green than
surrounding vegetation. Cattails, reeds, mosses, and other marsh vegetation often become
- established in a seepage area. However, in many instances, indicators of seeps do not
necessarily indicate the presence of seeps. Areas of apparent iron staining and/or excess iron
bacteria may also indicate the presence of a seep.
Locations of seepage at the ground surface adjacent to the ash basin have been identified and
are shown in Figure 2. These areas include the earthen embankments which impound the ash
basin as well as adjacent areas where water from the ash basin may have infiltrated into the
underlying residual materials and expressed as seepage.
l;
2.4.1 Engineered Drainage System for Earthen Dam
Earth dams are subject to seepage through the embankment, foundation, and abutments.
Seepage control is necessary to prevent excessive uplift pressures, instability of the
downstream slope, piping through the embankment and/or foundation, and erosion of material
by migration into open joints in the foundation and abutments. The control of seepage is
performed by the use of engineered drains such as blanket drains, trench drains, and/or toe
drains. In certain cases horizontal pipes may be installed into the embankment to collect and
control seepage. It is standard engineering practice to collect the seepage and convey seepage
away from the dam.
The Weatherspoon Ash Basin Dam was constructed with a drainage system, such as toe
drains, or outfalls, associated with the ash basin dam, which are shown as required by GS
130A-309.210(a)(2)(i) on Figure 2.
f �
2.4.2 Non -Engineered Seep Identification
Topographic maps of the site were reviewed to identify regions of the site where there was a
potential for ash basin related seepage to be present. These regions were determined by
comparing ash basin full pond elevations to adjacent topography with ground surface elevations
lower than the ash basin full pond elevation. Synterra staff performed site observations within
these identified areas as part of NPDES inspections during the reapplication process during
August 2014 and documented locations where seepage was apparent at the time of the site
visit. These seeps are identified as required by GS 130A-309.210(a)(2)(ii) on Figure 2.

Duke Energy Progress, LLC I Discharge Assessment Plan♦�
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SECTION 3 - DISCHARGE ASSESSMENT PLAN
Section 3 - Discharge Assessment Plan
3.1 Purpose of Assessment
The purpose of the assessment is to determine whether existing, known discharges from toe
drain outfalls, seeps, and weeps associated with the coal combustion residuals surface
impoundment (ash basin) have reached the surface waters of the State and have caused a
violation of surface water quality standards as required by North Carolina General Statute 130A-
309.210(b).
Figure 2 and Table 1 present the background and downstream sampling locations to be
considered as part of this Discharge Assessment Plan (DAP). These locations may be
assessed by comparing surface water sampling analytical results of the associated background
location with the corresponding downstream location. For discharges located at the toe of a
dam, an upstream location within the channel may not have been possible to isolate for
comparison given the proximity to the ash basin, which would have the same chemical
composition as the discharge itself. As such, the upstream location was established upstream of
the ash basin and is considered "background." For discharges located a distance from the ash
basin, an identified upstream, or "background" location for sampling may be compared to the
downstream portion of the discharge channel. The background and downstream sampling
locations are shown on Figure 2 with "B" and "D" identifiers, respectively, and the corresponding
seep locations associated with the sampling locations are indicated on Table 1.
3.2 Assessment Procedure
The assessment procedure associated with the Weatherspoon Plant ash basin is provided
within this section. In addition to the specific requirements for the assessment, Section 3.2 also
provides the general requirements, the frequency of assessment, documentation requirements,
and a description of the surface water quality analyses that will be performed.
3.2.1 General Assessment Requirements
Assessments are to be performed in three phases as follows:
• Observation and sampling (assessment site visit),
• Evaluation, and
• Assessment reporting.
The assessment site visit shall be performed when the background and downstream locations
are accessible and not influenced by weather events. Locations on or adjacent to the ash basin
embankments should be performed within two months after mowing, if possible. In addition, the
assessment site visit should not be performed if the following precipitation amounts have
i occurred in the respective time period preceding the planned assessment site visit:
• Precipitation of 0.1 inches or greater within 72 hours or
• Precipitation of 0.5 inches or greater within 96 hours.
The assessments shall be performed under the direction of a qualified Professional Engineer or
- Professional Geologist on a semi-annual basis within two nonadjacent quarters. The date of the
6

Duke Energy Progress, LLC I Discharge Assessment Plan W.H.1J�
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SECTION 3 - DISCHARGE ASSESSMENT PLAN
initial assessment site visit shall be selected no later than 30 days from the approval of the
Discharge Assessment Plan and should fall within one of the semi-annual timeframes.
Additional seep locations that may have been identified and documented in an Identification of
New Discharge report(s) shall be reviewed prior to performing an assessment site visit, if
available.
3.2.2 Observation and Sampling
Jurisdictional determinations regarding the extent of waters of the United States and their
relationship with identified seeps at the subject facilities will be obtained from the United States
Army Corps of Engineers (USACE). Until jurisdictional determinations are finalized by USACE,
preliminary information will be used to evaluate the seeps as described in the section below.
The initial assessment site visit should be performed to document baseline conditions of the
discharge channel, including location, extent (i.e., dimensions of affected area), and flow of
each discharge. Discharge channel background and downstream locations should be verified
using a Global Positioning System (GPS) device. Photographs should be taken from vantage
points that can be replicated during subsequent semi-annual assessments.
Initial and subsequent assessment site visits shall document a minimum of the following to
respond to the requirements in 130A-309.21 0.1 (b):
• Record the most recent ash basin water surface elevation and compare to the seep and
outfall and associated discharge location surface water elevations.
• For each discharge channel, the observer shall note the following as applicable on the
day of the assessment site visit:
o Is the discharge channel flowing at the time of the assessment site visit?
o Does the discharge channel visibly flow into a Water of the U.S. at the time of the
assessment site visit?
o How far away is the nearest Water of the U.S.?
o Document evidence that flow has or could reach a Water of the U.S. (e.g.,
description of flow, including extent and/or direction) and describe the observed
j condition. Evidence that flow could or has reached a Water of the U.S. may be
indicated by an inspection of the adjacent and downstream topographic drainage
features.
o Observe and document the condition of the discharge channel and outfall of the
engineered channel or seep location with photographs. Photographs are to be
taken from similar direction and scale as photographs taken during the initial
assessment site visit.
• Record flow rate within the discharge channel, if measureable, using the following
methods:
r1

Duke Energy Progress, LLC I Discharge Assessment Plan W.H.)l
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SECTION 3 - DISCHARGE ASSESSMENT PLAN
o Timed -volumetric method: Collect a volume of water from the discharge of the PVC
pipe directly into an appropriately sized container. Measure volumes (in mL) in the
field utilizing a graduated container. Record the amount of time (in seconds)
needed to collect the volume of water and calculate the flows (in MGD) for the
timed -volume.
o A V-notch weir apparatus will be installed, if necessary, during the initial
assessment site visit to impound seepage at locations with a defined channel.
Once the impounded seep reaches equilibrium discharge, flows will be measured
using the timed -volumetric method described above.
o Area -velocity method: Measure point velocities and water depth at a minimum of 20
stations along a transect setup perpendicular to the direction of flow using a
Swoffer® 3000 flow meter mounted to a standard United States Geologic Survey
(USGS) top -set wading rod. Utilize the average velocity and cross -sectional area of
the wetted channel to calculate flows in MGD.
• Collect water quality samples using the following methods:
o Collect background and downstream samples during a period with minimal
preceding rainfall to minimize potential effects of stormwater runoff. Sampling
procedures should prevent the entrainment of soils and sediment in water samples
that can result in analytical results not being representative of the flow. Because
Areas of Wetness (AOWs)/seeps often have poorly defined flow channels and
minimal channel depth, conventional grab samples collected directly into laboratory
containers or intermediate vessels is not possible without disturbance and
entrainment of soils and sediments. Further, many AOWs are contiguous with low-
lying areas subject to surface water runoff and resulting heavy sediment loading
during storm events or are near surface waters subject to flooding such that
representative samples of the AOW cannot be obtained. If the facility is unable to
obtain an AOW sample due to the dry, low flow or high flow conditions preventing
the facility from obtaining a representative sample, a "no flow' result or "excessive
flow" will be recorded.
o After collection, samples will be preserved and stored according to parameter
specific methods and delivered to the laboratory under proper Chain -of -Custody
(COC) procedures.
o Analytical parameters for analysis include: Fluoride, Arsenic, Cadmium, Copper,
Chromium, Nickel, Lead, Selenium, and Mercury. This list includes all parameters
previously identified for seep sampling at Duke Energy power plants for which
relevant stream water quality standards are in place. (This list is responsive to the
statutory requirement for the discharge assessment to allow determination whether
discharges from toe drain outfalls, seeps, or weeps have reached surface waters
and caused a violation of surface water quality standards.) Analyses shall be
conducted by Duke Energy's Huntersville Analytical Laboratory (NC Wastewater
r�
Certification #248) and Pace Analytical Laboratories (NC Wastewater Certification

Duke Energy Progress, LLC I Discharge Assessment Plan �1J�
W. H. Weatherspoon Power Plant Ash Basin
SECTION 3 - DISCHARGE ASSESSMENT PLAN
# 12). Laboratory analytical methods used for each constituent are provided in
Table 2.
o Seep in -situ measurements: In -situ field parameters (temperature and pH) shall be
measured utilizing calibrated field meters either at the discharge of the seep
directly, at the discharge of the flow measurement devices, or in the water pool
created behind the device, if sufficient water depth did not exist at the device
discharge.
o Lumber River and Ash Basin Sample Collection Method: Water quality samples
and in -situ measurements from the Lumber River shall be collected at a location
upstream and downstream of the ash basin. Additionally, water samples and in -situ
measurements shall be collected from an in -process ash basin location. The grab
samples shall be collected from the river and basin's surface (0.3 m) directly into
appropriate sample bottles.
• In addition to sampling conducted with the semi-annual assessments, additional seep
sampling will be conducted at locations and at a frequency as determined through
discussions with NC DEQ personnel.
3.2.3 Evaluation
Evaluation of the data from the initial assessment site visit will establish baseline conditions and
will serve as the basis for comparison for subsequent assessment site visit results. Evaluation of
observations and sampling results shall include location, extent (i.e., dimensions of affected
area), and flow of each discharge. The analytical results of the upstream and downstream
locations shall be compared to the 15A NCAC 2B standards for surface water quality upon
j receipt to identify potential exceedances.
3.2.4 Assessment Reporting
Each assessment site visit shall be documented by the individual performing the assessment,
as described in Section 3.2.2 to meet the requirements in 130A-309.21 0.1 (b). The report should
contain site background, observation and sampling methodology, and a summary of the
observations and descriptions of the discharge channels observed, changes in observations
compared to previous assessment events, estimates of flows quantities, and photographs of
discharges and outfalls of engineered channels designed or improved for collecting water from
the impoundment. Photographs are to be numbered and captioned. The flow and analytical
results shall be recorded and presented in tables similar to the examples provided as Tables 1
and 3. The analytical results shall be compared to the 15A NCAC 2B standards for surface
water quality and exceedances highlighted. This information shall be compiled, reviewed, and
submitted to NC DEQ within 90 days from the Observation and Sampling event.

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SECTION 4 - REFERENCES
Section 4 - References
Giese, G.L. Eimers, J.L., and Coble, R.W. 1997. Simulation of Ground -Water Flow in the
Coastal Plain Aquifer System of North Carolina, United States Geological Survey
Professional Paper 1404-M.
North Carolina Department of Environment and Natural Resources. 2007. Dam Operation,
Maintenance, and Inspection Manual, North Carolina Department of Environment and
Natural Resources, Division of Land Resources, Land Quality Division, 1985 (Revised
2007).
North Carolina Department of Natural Resources and Community Development. 1985. Geologic
Map of North Carolina.
Stuckey, J.L. 1965. North Carolina: Its Geology and Mineral Resources, Raleigh, North Carolina
Department of Conservation and Development, 550p.
Winner, M.D., Jr., and Coble, R.W. 1989. Hydrogeologic Framework of the North Carolina
Coastal Plain Aquifer System: U.S. Geological Survey Open -File Report.
10

FIGURES
I:1►iIC
TABLES

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WT
Traftr
PROPERTY BOUNDARY k
500' COMPLIANCE►
O' %� L(��yg �• - 'jdBOUNDARY .+
WASTE _�•, <y i r
BOUNDARY r I
! Pubbc 9ost
nd
�, ;" ,•may `, � � �-" �� � `•
ez
4.
r
i�
f \ , ant
bo
a-y her J�Q 3ra
NOTES:
I. SOURCE: USGS TOPOGRAPHIC MAP OBTAINED FROM
GEOSPATIAL DATA GATEWAY AT
HTTP://DATAGATEWAY. NCRS. USDA. GOV/
SCALE (FEET)
1,000 0 1,000 2,000
SITE LOCATION MAP DATE
DUKE ENERGY PROGRESS DEC. 16, 2014
WEATHERSPOON POWER PLANT
NPDES PERMIT #NC0005363 FIGURE
��u hrt«mp= LUMBERTON, NORTH CAROLINA

Table 3 - Weatherspoon Plant - Example Flow and Analysis Results Table
Parameter-.f.
Fluoride
Hg - Mercury (71900)
As - Arsenic (01002)
Unit
mg
{Jgl
14
Cd - Cadmium (01027)
IJgi
Cr - Chromium (01034)
IJg,
Cu - Copper (01042)
IJg,
Pb - Lead (01051)
Ni - Nickel (01067)
lig,
lig.
Se - Selenium (01147)
IJg
pH
SA
Temperature
°C
Flow
MG
s
�S-01.1-.
S-02
S-03'
S-04 :.
...S-05-..
.'"- 5-06 ;_:.. `:
;"' .: S-07.
S-08 --
S-09."
S-10..
g-1.1_
< 0.1
NS
0.19
NS
0.23
< 0.1
< 0.1
< 0.1
< 0.1
NS
NS
I
< 1
NS
< 1
NS
< 1
< 1
< 1
< 1
< 1
NS
NS
7.41
NS
292
NS
43.8
6.1
< 1
< 1
1.59
NS
NS
< 1
NS
< 1
NS
< 1
< 1
< 1
< 1
< 1
NS
NS
< 1
NS
< 1
NS
< 1
1.72
< 1
< 1
< 1
NS
NS
< 1
NS
< 1
NS
< 1
2.47
< 1
< 1
< 1
NS
NS
< 1
NS
< 1
NS
< 1
2.39
< 1
< 1
< 1
NS
NS
1
< 1
NS
25.6
NS
18.0
6.73
< 1
< 1
2.22
NS
NS
< 1
NS
< 1
NS
< 1
< 1
< 1
< 1
< 1
NS
NS
6.5
NS
7.3
NS
7.3
6.6
6.7
6.6
7.0
NS
NS
25
NS
25
NS
25
28
25
24
29
NS
NS
D
NF
NS
0.06172
NS
0.01987
NF
0.01267
0.00141
0.03016
NS
NS
Notes:
1. Flow measurements and analytical samples were collected on August 18-19, 2014.
2. NF - Stream flow not present during this sampling event or too low to be measured.
3. NS - No surface water present during this sampling event. Evidence of seasonal wetness.

Table 1— Weatherspoon Steam Station Ash Basin — Seep and Associated Discharge Locations and Descriptions
Location Coordinates
Flow -
:
Discharge Location
Seep / :
NAD e3
.l t
Flow
Measurement
•
Background
Discharge Location and Discharge Sampling '
Coordinates
. ' . sat
DischargelD
Description
• (MGD)and
Locaton
Location
Latitude
Longitude
Latitude
Longitude,
Method_
' '
S-01
34.593324
-78.973004
Continuous
NF
Discharged to Wastewater Effluent
Around riprap pile on northeast side of ash basin
S-02
34.593513
78.969757
Intermittent
NS
2-D
0.06172
At toe of dike on east side of ash basin
S-03
34.591892
-78.967913
Continuous
area -velocity
1-9
2-D
34.589175
-78.965478
Southeast face of ash basin dike
S-04
34.589755
-78.966327
Intermittent
NS
2-D
0.01987
East side of ash basin at toe of dike
S-05
34.589871
-78.965880
Continuous
area -velocity
2-13
North of railroad tracks
S-06
34.593088
-78.973552
Continuous
NF
2 B
3-D
34 587675
-78.978144
S-07
34.588211
-78.977747
Continuous
0.01267
48' concrete pipe flowing toward S-18 and -22
timed -volumetric
3-D
0.00141
48' concrete pipe flowing toward S-18 and -22
S-08
34.588199
-78.977730
Continuous
timed -volumetric
3-D
S-09
34.590244
-78.973407
Continuous
0.03016
Discharged to Wastewater Effluent
area -velocity
Immediately at toe of dike face of west side of ash
S-10
34.589208
-78.971123
Intermittent
NS
basin
1-B
2-D
Western toe/engineered outfall from ash basin
5-11
34.586537
-78.968071
Intermittent
NS
2-D
34.589175
-78.965478
Second westernmost toe drain from ash basin
5-12
34.588729
78.967785
Intermittent
NS
2-D
Second easternmost toe drain from ash basin
S-13
34.588896
-78.967469
Intermittent
NS
2-D

Discharge Location
Seep/
Location Coordinates
tNno e31
Flow -'
Flow' ;
Back round
:
-Discha Location and DISCh'ar a Sam. Im
Coordinates
.Measurement' -
9.
'Location-
a
r9 9 P 9
tonDeat_ ,
Discharge ID.
,Description
(MGD),and . -
'
location -
Method _'
: Latitude'
Longitude =
Latitude
- Longitude
0.00061
Eastern toe drain from ash basin
5-14
34.589052
78.967185
Continuous
timed -volumetric
2-D
0.08781
Channel along south edge of ash basin; captures
S-15
34.589240
-78.966433
Continuous
flows from S-10to -14.
area -velocity
2-D
S-16
34.587238
-78.969535
Continuous
0.02020
Discharged to Wastewater Effluent
-
-
area -velocity
Upstream
3-13
Just below public boat ramp
S-17
34.591216
-78.982946
Surface
Water
NM
4 D
34.565589
-78.970033
0.01372
2-B
Concrete pipe downstream of S-07 and -08
S-18
34.587809
-78.978069
Continuous
timed -volumetric
3-D
34 587675
-78.978144
Downstream
500 ft south of cooling pond
S-19
34.567428
-78.969752
Surface
Water
NM
4-D
3-B
34.565589
-78.970033
Upstream
Jacob Swamp water upstream from plant at Old
S-20
34.593876
-78.958137
Surface
NF
Whiteville Road
Water
4-D
Ash Pond
1-B
Wastewater from southeast comer of ash basin
S-21
34,590123
-78.967084
Water
NF
34 589175
-78-965478
2-13
Concrete pipe underneath old dike adjacent to
5-22
34.587810
-78.978079
Intermittent
NS
Lumber River
34.587675
-78.978144
3-D
Notes:
1. Flow description for each seep sample location is based on observation during site visits performed by Synterra in August 2014.

Table 2 — Laboratory Analytical Methods
- Parametee
Method,:.
Reporting
Units..
Laboratory ;,
Fluoride (F)
EPA 300.0
1
mg/I
Duke Energy
Mercury (Hg)
EPA 245.1
0.05
Ng/I
Duke Energy
Arsenic (As)
EPA 200.8
1
Ng/I
Duke Energy
Cadmium (Cd)
EPA 200.8
1
Ng/I
Duke Energy
Chromium (Cr)
EPA 200.8
1
Ng/I
Duke Energy
Copper (Cu)
EPA 200.8
1
Ng/I
Duke Energy
Lead (Pb)
EPA 200.8
1
Ng/I
Duke Energy
Nickel (Ni)
EPA 200.8
1
Ng/I
Duke Energy
Selenium (Se)
EPA 200.8
1
Ng/I
Duke Energy