NC0003425_Fact Sheet_20160823

DEPARTEMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WATER RESOURCES
FACT SHEET FOR NPDES PERMIT DEVELOPMENT
NPDES No. NC0003425
Summary
The Roxboro Steam Electric Plant is an electric generating facility that uses steam turbine
generation (via four coal-fired units with a total net capacity of 2558 MW). Units No. 1 and 2
(385 MWe and 670 MWe, respectively) use condensers as cooling devices. Units No. 3 and 4
(707MWe and 700 MWe, respectively) use cooling towers as cooling devices.
The facility has three existing cooling water intake structures (CWISs). The source water for
CWISs No.1 and 2 is the Hyco Reservoir. The source water for CWIS no. 4 is the sites cooling
canal. The facility total intake is approximately 1,114 MGD. The facility discharges to subbasin
030205 in the Roanoke River Basin. Discharges are mostly industrial, with a very small
domestic flow (internal Outfall 008) piped to the on-site ash pond. Discharges from the ash
pond (internal Outfall 002), once -through cooling water and FGD treat -met sytem (internal
outfall 010) are discharged to the Discharge Canal (outfall 003). The Discharge Canal and Coal
Pile Runoff (outfall 006) both discharge to Hyco Reservoir. The Hyco Reservoir is a 17.6 km2
waterbody constructed in 1963 by CP&L to serve as a cooling water source. The receiving
waterbody is class WS -V; B. The facility is located in the Lower Piedmont area of the state, the
applicable state water quality temperature standard is 3TC (89.6° F).
This facility is subject to EPA effluent guideline limits per 40 CFR 423 - Steam Electric Power
Generating Point Source Category which were amended November 3, 2015. The facility is also
subject to the Cooling Water Intake Structures Rules (40 CFR 125) effective October 14, 2014.
The intake flow is > 125 MGD.
Facility Information
Applicant/ Facili Name:
Applicant,.A ddress:
Duke Ener Progress/Roxboro Steam Electric Generatin Plant
1700 Dunnawav Rd., Semora, NC 27343
Facility Address:
1700 Dunnawa Rd., Semora, NC 27343
Permitted Flow
Not limited
Type of Waste:
99.8 % Industrial, 0.2% - domestic
Facility/Permit Status:
Existing/ Renewal
Person
-County:
Miscellaneous
Receiving Stream:
Hyco Reservoir
Stream
Classification:
WS -V, B
Subbasm:
03-02-05
303(d) Listed?:
No
Drainage Area (mi2):
Summer 7Q10 cfs)
30Q2 cfs):
Average Flow cfs :
Lake
0
0
0
Primary SIC Code:
Regional Office:
Quad
Permit Writer:
4911
RRO
Olive Hill
Teresa Rodriguez
IWC (%):
100%
Date:
8/23/2016
Summary
The Roxboro Steam Electric Plant is an electric generating facility that uses steam turbine
generation (via four coal-fired units with a total net capacity of 2558 MW). Units No. 1 and 2
(385 MWe and 670 MWe, respectively) use condensers as cooling devices. Units No. 3 and 4
(707MWe and 700 MWe, respectively) use cooling towers as cooling devices.
The facility has three existing cooling water intake structures (CWISs). The source water for
CWISs No.1 and 2 is the Hyco Reservoir. The source water for CWIS no. 4 is the sites cooling
canal. The facility total intake is approximately 1,114 MGD. The facility discharges to subbasin
030205 in the Roanoke River Basin. Discharges are mostly industrial, with a very small
domestic flow (internal Outfall 008) piped to the on-site ash pond. Discharges from the ash
pond (internal Outfall 002), once -through cooling water and FGD treat -met sytem (internal
outfall 010) are discharged to the Discharge Canal (outfall 003). The Discharge Canal and Coal
Pile Runoff (outfall 006) both discharge to Hyco Reservoir. The Hyco Reservoir is a 17.6 km2
waterbody constructed in 1963 by CP&L to serve as a cooling water source. The receiving
waterbody is class WS -V; B. The facility is located in the Lower Piedmont area of the state, the
applicable state water quality temperature standard is 3TC (89.6° F).
This facility is subject to EPA effluent guideline limits per 40 CFR 423 - Steam Electric Power
Generating Point Source Category which were amended November 3, 2015. The facility is also
subject to the Cooling Water Intake Structures Rules (40 CFR 125) effective October 14, 2014.
The intake flow is > 125 MGD.

NPDES PERMIT FACT SHEET
Page 2
Roxboro Steam Electric Plant
NPDES No. NC00003425
The facility operates five internal outfalls and two outfalls to Hyco Reservoir. Duke requested
the addition of two new outfalls on the permit; one to reflect the future treatment system for the
low volume wastes as the ash basin will be closed and one for seeps and stormwater.
Description of existing outfalls:
• Outfall 003 - Heated Discharge Canal to Hyco Reservoir. The discharge canal combines
all internal outfalls (002, 005, 008, 009, 010) before discharging to Hyco Reservoir. In
addition, once -through cooling water from condensers for units 1,2, and 3, once -through
cooling water from heat exchangers, seepage from ash pond, and stormwater runoff
from plant drainage areas are discharged to the discharge canal.
Outfa11006 - Coal Pile Runoff discharges directly to Hyco Reservoir. Coal pile runoff
wastewaters include runoff from the coal pile, limestone pile and gypsum pile, truck
wheel wash area and coal handling areas. Treatment is accomplished by neutralization,
sedimentation and equalization.
Internal Outfall 002 - Ash Pond discharging to the discharge canal. The ash pond
receives wastewater from the following source:
• Bottom ash transport waters
• Silo wash water
• Ash landfill leachate and runoff (this landfill receives CCR from Mayo and
Roxboro plants)
• Dry -ash handling system wash water
• Blowdown from Unit 4 cooling tower
• Coal mill rejects and pyrites
• Sewage treatment plant effluent
• Low volume waste consisting of boiler blowdown, equipment maintenance
cleaning wastewaters, RO reject wastewater and floor drains. Low volume
wastes are treated by neutralization.
• Emergency overflow from FGD system blowdown.
The ash pond uses precipitation, adsorption, and settling for treatment, which has been
determined by NC to be BAT for this facility.
• Internal Outfall 005 - Cooling tower blowdown from Unit 4.
• Internal Outfall 008 - Treated domestic wastewater. The treatment system consists of a
screen, communitor, surge tank, aeration tank, clarifier, chlorine contact chamber and
sludge holding tank. A new package plant will be installed to replace the existing plant.
• Internal Outfall 009 - Chemical metal cleaning waste. Wastewaters from cleaning of the
boilers is generated every five to eight years. Every three to five years wastewaters are
generated from cleaning the heat exchangers. The wastewaters generated can be treated
by evaporation or by neutralization and precipitation.
• Internal Outfall 010 - Flue Gas Desulfurization (FGD) .treatment system discharging to
the discharge canal. The scrubber system removes SOx by mixing flue gas with a

NPDES PERMIT FACT SHEET Roxboro Steam Electric Plant
Page 3 NPDES No. NC00003425
limestone slurry. The blowdown from the scrubber is discharged to a gypsum settling
pond system then to a bioreactor which utilizes microorganisms to reduce soluble
contaminants to insoluble forms (under anaerobic conditions) that then precipitate from
solution. Wastewater is discharged to the ash pond effluent channel. An emergency
overflow from the FGD system blowdown discharges to the ash pond.
Proposed Outfalls:
Outfall 001 (Seeps) - The facility identified 16 unpermitted seeps. Seven seeps are
engineered drains from the ash basin flowing to the discharge canal. Four non -
engineered seeps also flow to the discharge canal. Four seeps from the ash landfill and
one from the gypsum pile flow to the intake canal through a common outfall. This
outfall was previously designated as outfall 001 in the permit and will be reinstated to
monitor the seeps.
Internal Outfall 012 - Low volume waste and other wastewaters. Duke will build a new
dual basin treatment system to treat wastewaters than now go to the ash basin.
CWA 316 (b)
The permittee shall comply with the Cooling Water Intake Structure Rule per 40 CFR 125.95.
The Division approved the facility request for an alternative schedule in accordance with 40
CFR 125.95(a)(2). The permittee shall submit all the materials required by the Rule with the next
renewal application.
Temperature Mixing Zone - Outfall 003
The facility is located in the Lower Piedmont area of the state, the applicable state water quality
temperature standard is 32°C (89.6° F). The authorized temperature mixing zone for outfall 003
includes the North Hyco Arm downstream of NC Hwy 57, the main body of Hyco Reservoir
downstream of the confluence of the Cobbs Creek Arm and the North Hyco Arm and the entire
afterbay lake. USGS data at the afterbay monitoring station (USGS Station 02077303) was
reviewed for the period of January 2011 to April 2016. Data shows that the temperature water
quality standard was not exceeded for this period. Maximum temperature recorded was 30.5°C.
Instream Monitoring
The permit requires monitoring of Hyco Reservoir in accordance to the Biological Monitoring
Program as approved by the Division. Based on the Divisions review of the reports the fish
community is comparable to other piedmont reservoirs and no problems were noted.
DATA REVIEW/PERMIT REQUIREMENTS
Internal Outfall 002 - Ash Pond
This outfall is subject to the Effluent Limitations Guidelines (ELG) in Table 1.
Table 1. ELG Outfall 002 (Prior to November 1, 2018)
Pollutant Daily Maximum Monthly ELGAvera e
TSS 100 m / 1 30 m / 1 40 CFR 423.12 (b) (4
Oil & Grease 20 mg/1 15 mg/1 1 40 CFR 423.12 b 4

NPDES PERMIT FACT SHEET Roxboro Steam Electric Plant
Page 4 NPDES No. NC00003425
After November 1, 2018 no discharge of bottom ash transport water is allowed as per 40 CFR
423.13 (k) (1) (i). Compliance with this section shall be as soon as possible but no later than
December 31, 2023. Duke has submitted a schedule of compliance for meeting the rule by April
30, 2021. Fly ash transport water is not discharge so they will meet the compliance date of
November 1, 2018.
The current permit requires monitoring for flow and total selenium, limits for Oil & Grease and
TSS. A summary of DMR data for the period of January 2011 to January 2016 is included in
Table 2. There have been no violations of permit limits or conditions.
Table 2. DMR Summary Outfall 002
Parameter
Average
imum
Basis
Flow
10.8 MGD
48.3 MGD
3.1 MGD
TSS
5 m /l
21 m /l
< 2.5 m /l
Total Selenium
14.6 µ /l
68.8 µ /l
< 10 µ /l
O&G
<5m /l
13.5m /l
<5m /l
Table 3. Monitoring Requirements/ Proposed Changes Outfall 002
Parameter
Monitoring
Changes
Basis
requirements
Flow
Monitor
No changes
15A NCAC 2B.0505
TSS
30 mg/l monthly aver
No changes
40 CFR 423.12(b)(4)
100 m / 1 daily max
Oil & Grease
15 mg/l monthly aver
No Changes
40 CFR 423.12(b)(4)
20 m / 1 daily max
Total
Selenium
Monthly monitoring
No changes
Pollutant of concern.
Turbidity, pH
Pollutant of concern for
No requirement
Monitor
dewatering/ decanting
Internal Outfall 002 - Dewatering
To meet the requirements of the Coal Ash Management Act of 2014, the facility needs to
dewater two ash ponds by removing the interstitial water and excavate the ash to deposit it in
landfills. The facility's highest discharge rate from the dewatering process will be 1 MGD. The
facility submitted data for the standing surface water in the ash ponds, interstitial water in the
ash, and interstitial ash water that was treated by filters of various sizes. The following
pollutants were detected at concentrations higher than the water quality standards: selenium,
arsenic and molybdenum. A new effluent and monitoring sheet is included in the permit for the
ash pond dewatering phase. As this is an internal outfall the water quality standards are not
applied. Monitoring will be required for selenium, arsenic, molybdenum, antimony and copper.
Ash Pond Dams:
Seepage through earthen dams is common and is an expected consequence of impounding
water with an earthen embankment. Even the tightest, best -compacted clays cannot prevent
some water from seeping through them. Seepage is not necessarily an indication that a dam has
structural problems, but should be kept in check through various engineering controls and

NPDES PERMIT FACT SHEET
Page 5
Roxboro Steam Electric Plant
NPDES No. NC00003425
regularly monitored for changes in quantity or quality which, over time, may result in dam
failure.
Outfall 003 - Discharge Canal (Combined outfalls)
DMR/Compliance Review
Data were reviewed for the period of January 2011 to March 2016. There have been no
violations of permit limits or conditions.
TaW,, d nIMR gnmmary Outfall 003
Parameter 1 ` v N
Flow (MGD)
Average
840
Ma`
1130
6.9
TRC
Not dischar ed
_
TP (mg/1)
< 0.036
< 0.05
< 0.05
TN (mg/1)
0.68
1.08
0.44
Temperature °C
29
41
13°C
Total Arsenic µ / 1)
6.2
17.1
< 2.8
H SU
7.34
8
6.38
Toxicity Testing (003):
Current Requirement: Acute P/ F at 90%, February, May, August, November.
Proposed Requirement: Acute P/F at 90%, February, May, August, November.
The facility passed 21 tests out of 21 tests performed for the period of January 2011 to January
2016.
Reasonable Potential Analysis Outfall 003:
The Division conducted EPA -recommended analyses to determine the reasonable potential for
toxicants to be discharged at levels exceeding water quality standards/ EPA criteria by this
facility from outfall 003. For the purposes of the RPA, the background concentrations for all
parameters were assumed to be below detection level. The RPA uses 95 % probability level and
95% confidence basis in accordance with the EPA Guidance entitled "Technical Support
Document for Water Quality -based Toxics Control." With the approval of the Triennial Review
(2007-2014) of the NC Water Quality Standards by the Environmental Management
Commission (EMC) in 2014 and US -EPA (with some exceptions) on April 6, 2016, the NPDES
Permitting Unit is required to implement the new dissolved metal standards in all permits
public noticed after April 6, 2016. The RPA included evaluation of dissolved metals standards,
utilizing measured hardness value of 100 mg/L CaCO3 for hardness -dependent metals.
A reasonable potential analysis was conducted for arsenic, copper, nickel, selenium, strontium,
thallium, chlorides and zinc. Arsenic data used for the RPA was collected between 2011 and
2016. Data for the remaining parameters was from a special study for the period of March 2010
to August 2011. Based on this analysis, the following permitting actions are proposed for this
permit:
• Monitoring Only. The following parameters will receive a monitor -only requirement
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/ criteria, but the maximum predicted concentration was >50% of the
allowable concentration: Arsenic, selenium, chloride and thallium.
• No Limit or Monitoring: The following parameters will not receive a limit or monitoring,
since they did not demonstrate reasonable potential to exceed applicable water quality

NPDES PERMIT FACT SHEET Roxboro Steam Electric Plant
Page 6 NPDES No. NC00003425
standards/ criteria and the maximum predicted concentration was <50% of the
allowable concentration: copper, nickel, strontium, and zinc.
Mercury Evaluation Outfall 003:
A mercury evaluation was conducted in accordance with the permitting guidance developed
for the implementation of the statewide Mercury TMDL to determine the need for a limit and
Mercury Minimization Plan (MMP). Monitoring for mercury is not required for outfall 003 but
mercury data was collected during a special study during the period of March 2010 to August
2011. The water quality based effluent limitation (WQBEL) for mercury is 12 ng/1. The
technology based effluent limit (TBEL) is 47 ng/1. None of the annual averages exceeds the
WQBEL or TBEL, no limit is required. See the attached mercury evaluation spreadsheet.
Table 5. Mercury Evaluation
Table 6. Monitoring Requirements/Proposed Changes Outfall 003
2010
2011
# of Samples
20
16
Annual Average, n / L
3.6
4.4
Maximum Value, n / L
7.63
6.92
TBEL, n / L
47
WQBEL, n / L
12.0
Table 6. Monitoring Requirements/Proposed Changes Outfall 003
Monitoring
Parameter
requirements/Limits
Changes
Basis
Plow
Monitor
No changes
15A NCAC 213.0505
TRC
200 gg/1
Modified limit to
State WQ standards, 15A
instantaneous max
28 µg /1 daily max
NCAC 2B.0200. The water
quality standard is more
stringent than the effluent
idelines limit.
TP
Monitor
No changes
15A NCAC 2B.0500
TN
Monitor
No changes
15A NCAC 2B.0500
Temperature
Monitor
No changes
Approved Mixing zone
Total Arsenic
Monitor
No changes
Based on results from
RPA, Predicted
concentration greater than
50% of allowable.
Total Selenium
No requirement
Quarterly
Based on results from
monitoring
RPA, Predicted
concentration greater than
50% of allowable.
Total Thallium
No requirement
Quarterly
Based on results from
monitoring
RPA, Predicted
concentration greater than
50% of allowable.
Chloride
No requirement
Quarterly
Based on results from
monitoring
RPA, Predicted

NPDES PERMIT FACT SHEET
Page 7
Roxboro Steam Electric Plant
NPDES No. NC00003425
Internal Outfall 005 - Cooling Tower Blowdown from Unit 4
This outfall is subject to the ELGs in Table 7.
TaW, 7 FTC; n„tfa» nn.5
Pollutant,
Daily Maxi munmiT
Monthly
concentration greater than
Parameter
6 to 9 SU
0.5 mg/1
Avera �
0.2 mg/l
50% of allowable.
pH
6 to 9 SU
No changes
State WQ standards, 15A
Free available
500 µg/l daily max
126 Pollutants
NCAC 2B.0200
Acute toxicity
P/F 90%
No changes
State WQ standards,15A
0.2 mg/1
40 CFR 423.13 (d) (1)
Chromium
NCAC 2B.0200
Internal Outfall 005 - Cooling Tower Blowdown from Unit 4
This outfall is subject to the ELGs in Table 7.
TaW, 7 FTC; n„tfa» nn.5
Pollutant,
Daily Maxi munmiT
Monthly
, ELG
Parameter
6 to 9 SU
0.5 mg/1
Avera �
0.2 mg/l
40 CFR 423.12 (b) 1)
40 CFR 423.12 (d) (1)
H
Free Available
Chlorine
15A NCAC 2B.0505
Free available
500 µg/l daily max
126 Pollutants
No detectable amounts
40 CFR 423.13 d 1
Total
0.2 mg/1
0.2 mg/1
40 CFR 423.13 (d) (1)
Chromium
40 CFR 423.13 (d)(2)
Chlorine
Total Zinc
1.0 mg/ 1
200 g /1 dailymax
1.0 mg/1
40 CFR 423.13 d) (1)
The permit includes monitoring for flow and Total Residual Chlorine (TRC), limits for Free
Available Chlorine, Total Chromium, Total Zinc and 126 priority pollutants.
Special condition A. (14) in the permit doesn't allow the discharge of the cooling tower
blowdown to the discharge canal, it has to be discharged to the ash pond. With the
modifications planned to the site and the future closure of the existing ash pond Duke will like
to have the option to discharge the blowdown to the discharge canal. This will continue to be an
internal outfall subject to the same limits under 40 CFR 423. The limits apply before it comingles
with any other waste stream so there is no change in limits or other permit conditions by
allowing the cooling tower blowdown to discharge into the discharge canal.
DMR/ Compliance Review:
Data were reviewed for the period of January 2011 to January 2016. There have been no
violations of permit limits or conditions. Flow was the only parameter monitored at this outfall
since the facility did not chlorinate or added chromium or zinc for maintenance activities. Flow
is reported as 7.2 MGD on a daily basis.
rr W Q 'N4- i;lv,r;ncr RPn,,;rPmonta/Pronosed Changes Outfall 005
Monitoring
Changes
g
Basis
Parameter
Requirements/Limits
Flow
Monitor
No changes
15A NCAC 2B.0505
Free available
500 µg/l daily max
No changes
40 CFR 423.13 (d)(1)
chlorine
200 µ /l monthly avera e
Total Residual
Monitoring
No changes
40 CFR 423.13 (d)(2)
Chlorine
Total chromium
200 g /1 dailymax
No changes
40 CFR 423.13 d) 1)

NPDES PERMIT FACT SHEET
Page 8
Roxboro Steam Electric Plant
NPDES No. NC00003425
Outfall 006 - Coal Pile Runoff
This outfall is subject to the ELG in Table 9.
Table 9. ELG Outfall 006
Pollutant
200 µ /1 monthly average
Monthly ELG., f
Average -
TSS _-
Total Zinc
1.0 mg/l daily max
No changes
40 CFR 423.13 (d)(1)
TSS (mg/1)
1.0 m / 1 monthly average
76.6
< 2.5
The 126 priority
pollutants
No detectable amount
No changes
40 CFR 423.13 (d)(1)
Outfall 006 - Coal Pile Runoff
This outfall is subject to the ELG in Table 9.
Table 9. ELG Outfall 006
Pollutant
Daily Maximum
Monthly ELG., f
Average -
TSS _-
50m /1
40 CFR 423.12 b) 9
H
6 to 9 SU 40 CFR 423.12 b) 1)
DMR/Compliance Review:
Data were reviewed for the period of January 2008 to March 2013. There have been no
violations of permit limits or conditions.
Table 10. DMR Summary Outfall 006
Parameter
Average
Maximum
Minimum
Flow MGD
0.23
0.05
0.002
TSS (mg/1)
2.6
76.6
< 2.5
H (SU)
7.39
8.9
6.04
Priority Pollutant Scan:
The application included the results of one scan. Selenium was detected above the water quality
standard. Monitoring for selenium was added to the permit.
Table IL Monitoring Requirements/ Proposed Changes Outfall 006
Parameter
Monitoring
Changes
Basis
requirements/Limits
Flow
Monitor
No changes
15A NCAC 2B.05
TSS
50 mg/l instantaneous
Added Monthly
40 CFR 423.12(b)(9),
averagelimit of 30
max
1 ge
40 CFR 122.45
H
6 to 9 SU
No changes
40 CFR 423.12 1
Total selenium
No requirement
Quarterly Monitoring
Detected in the PPA
Acute toxicity
P/F 90%
No changes
State WQ standards,
15A NCAC 2B.0200

NPDES PERMIT FACT SHEET
Page 9
Internal Outfall 008 - Domestic WWTP
Tl-,l0 1 7 M41? ROXAOXA7 C)114all 009
Roxboro Steam Electric Plant
NPDES No. NC00003425
Parameter
Average
Maximum
Minimum
Flow (MGD)
0.007
0.01
0.002
TSS (mg/ 1
14.7
30
5
H SU
6.8
7.3
6.5
BOD (mg/1)
10.4
28
2.1
NH3N (mg/ 1)
0.8
1.6
secondary treatment of
Table 13 Monitoring Requirements/Proposed Changes Outfall 008
Parameter
Monitoring
Changes
Basis
Flow
requirements/Limits
No changes
15A NCAC 2B.0505
Floe
0.015 MGD
Add effluent page
WWTP will be upgraded
1.0 mg/1 daily max
for 0.025 MGD
during this permit cycle
TSS
30 mg/1 monthly aver
No changes
NPDES rules for
45 mg/1 daily max
secondary treatment of
TSS
30 mg/1 monthly aver
No changes
domestic wastewater,
100 mg/1 dail max
15A 2B.0400
pH
6 to 9 SU
No changes
State WQ standards, 15A
20 mg/ 1 daily max
2B.0200
BOD
30 mg/1 monthly aver
No changes
NPDES rules for
45 mg/1 daily max
secondary treatment of
domestic wastewater,
15A 2B.0400
Total
Monitor
No changes
DWQ Policy
ammonia
Internal Outfall 009 - Chemical cleaning waste
Tol,ln 1d Mnn;+nr;nQ Ran,,;romPnts/Proposed Changes Outfall 009
Parameter
Monitoring
requirements/Limits
Changes
Basis
Flow
Monitor
No changes
15A NCAC 2B.0505
Total Copper
1.0 mg/1 monthly aver
No changes
40 CFR 423.13 (e)
1.0 mg/1 daily max
Total Iron
1.0 mg/1 monthly aver
No changes
40 CFR 423.13 (e)
1.0 m / 1 daily max
TSS
30 mg/1 monthly aver
No changes
40 CFR 423.13 (e)
100 mg/1 dail max
Oil & Grease
15 mg/1 monthly aver
No changes
40 CFR 423.13 (e)
20 mg/ 1 daily max
Internal Outfall 010 - FGD
This outfall is subject to the Effluent Limitations Guidelines (ELG) in Table 15. These are new
limitations promulgated November 3, 2015.

NPDES PERMIT FACT SHEET
Page 10
Table 15. ELG Outfall 01.0
Roxboro Steam Electric Plant
NPDES No. NC00003425
Pollutant
Daily Maximum
Maximum
Monthly
Averse
Flow MGD
ELG
1.77
H
Total Beryllium. (gg/1)
6 to 9 SU
10
40 CFR 423.12
b 1
TSS
100 mg/1
< 1
30 mg/1
102
40 CFR 423.12
) 11)
Oil and grease
20 m
/ 1
15 mg/1
40 CFR 423.12
b) 11
Total Arsenic
11 µ
/1
8 µ
/1
40 CFR 423.13
1 i
Total Mercury
788 ng/1
356 ng/1
40 CFR 423.13
1 i
Total Selenium
23 µ
/1
12 µ
/1
40 CFR 423.13
) 1) i
Nitrate/nitrite
17 mg/
1
4.4 mg/1
40 CFR 423.13
1) i)
The rule establishes compliance dates for the new limitations. Permittee must meet limits as
soon as possible beginning on November 1, 2018 but no later than December 31, 2023. Duke will
construct a new treatment system and requested a compliance date of December 31, 2023. As
the new treatment system will be placed in operation and the old pond may still discharge until
it is decommissioned. A new outfall is included in the permit for the new systern.
The current permit includes monitoring for flow, total beryllium, total mercury, total antimony,
total selenium, total silver and total vanadium. Table 16 includes a summary of DMR data for
the period of January 2011 to January 2016. There have been no violations of permit limits or
conditions.
Table 16. DMR Summar Outfall 010
Parameter
Average
Maximum
Minimum
Flow MGD
0.84
1.77
0.01
Total Beryllium. (gg/1)
3.9
10
< 1
Total Mercury µ / 1
1.08
9.6
< 1
Total Selenium (gg/1)
102
712
< 50
Total Silver (gg/1)
6
8.4
< 5
Total Antimony (gg/1)
31
70
< 25
Total Vanadium (gg/1)
< 25
< 25
< 5
Table 17. Monitoring Requirements/Proposed Changes Outfall 010
Parameter
Monitoring
requirements/Limits
Changes
Basis
_
Flow
Monitor
No changes
15A NCAC 213.0505
Total Beryllium
MonitorRemove
monitoring
Internal outfall, not a
parameter of concern.
Total Vanadium
Monitor
Remove monitoring
Internal outfall, not a
parameter of concern.
Total Antimony
Monitor
Remove monitoring
Internal outfall, not a
parameter of concern.
Total Silver
Monitor
Remove monitoring
Internal outfall, not a
arameter of concern.

NPDES PERMIT FACT SHEET
Page 11
Roxboro Steam Electric Plant
NPDES No. NC00003425
Total Arsenic No monitoring Add limits of 11 µg/1
daily maximum and 40 CFR 423.13 (g) (1) (i)
8 µg/l monthly
average
Total Selenium Monitor Add limits of 23 µg/1
daily maximum and 40 CFR 423.13 (g) (1) (i)
12 µg/1 monthly
Nitrate/Nitrite No monitoring Add limits of 17
mg/ 1 daily
maximum and 4.4 40 CFR 423.13 (g) (1) (i)
mg/ 1 monthly
Total Mercury Monitoring Add limits of 788
ng/1 daily maximum 40 CFR 423.13 (g) (1) (i)
and 356 ng/1
monthly average.
Proposed Outfalls:
Outfall 001
The facility identified 16 unpermitted seeps. Data collected on the seeps was reviewed to
determine the need for limits. Five seeps discharge to the intake canal at Hyco Reservoir. The
point of discharge is where former Outfall 001 used to discharge. The Division will reinstate
outfall 001 to monitor the discharge from the seeps.
Table 18. Outfall 001 Proposed Limits/Mori
Parameter — _ Monitorin
Flow Monitor
pH 11
Total copper, total antimony,
total lead
Fluoride
Total Arsenic
Total Selenium
Sulfites
Monitor
imus f
-s
15A NCAC 2B.0505
State WQ standards, -15A 2B
.0200
Detected below the wqs
Limit -18 mg/l
Limit -10 µg/l
Limits 5 µg/1 Monthly Average
56 µg/l Daily Max
Limit - 250 mg/1 (Monthly
average & daily max)
TDS, Hardness, Conductivity I Monitor
Acute toxicity
Quarterly Limit
Detected above the wqs
Detected above the wqs
Detected above the wqs
Detected above the wqs
Parameters of concern
State WQ standards, 15A
NCAC 2B.0200
The remaining 11 seeps all drain to the discharge canal near the ash basin, 7 of those are
chimney drains from the ash basin dam. The flow from the combined seeps account for less
than 0.0005 % and will be included in the authorized wastewaters discharging through outfall
003.

NPDES PERMIT FACT SHEET
Page 12
Roxboro Steam Electric Plant
NPDES No. NC00003425
Internal Outfall 012
A new treatment system will be installed to divert wastewaters from the ash basin. The
proposed system consists of two lined basins discharging to the effluent discharge canal. Low
volume wastes, metal cleaning wastes, stormwater, and other miscellaneous wastes that are
routed to the ash basin will be routed to this new treatment system.
Table 19. Outfall 012 Proposed Limits/ Monitoring:
Parameter
Monitoring
Basis
requirements/Limits
Flow
Monitor
15A NCAC 2B.0505
Total Suspended Solids
30 mg/1 Monthly Average
40 CFR 423.12 (b)(3)
100 mg/1 Daily Max
Oil & Grease
15 mg/1 Monthly Average
40 CFR 423.12 (b)(3)
100 m / 1 Daily max
ADDITIONAL CHANGES TO PERMIT
• A separate effluent page for the dewatering of the ash ponds (Outfall 002) was added to the
permit.
• Outfall 001 was reinstated to monitor discharge of seeps and stormwater.
• A new internal outfall (Outfall 011) was added to the permit to monitor the discharge from
the proposed FGD treatment system.
• A new internal outfall (Outfall 012) was added to the permit for the proposed retention
basin for wastewaters previously treated in the ash pond.
• Special Condition A.(14) that prohibited the discharge of cooling tower blowdown from
outfall 005 to the discharge canal was eliminated from the permit.
• A special condition was added to describe Section 316(b) requirements for submittal of
applicable information.
• A special condition was added to the permit to require an Ash Pond Closure Plan
• A Special Condition was added to the permit to require compliance with Senate Bill 729
(Coal Ash Management Act).
• Attachment 1 entitled "Groundwater Monitoring Plan" was added to the permit.
PROPOSED SCHEDULE FOR PERMIT ISSUANCE
Draft Permit to Public Notice: August 24, 2016
Permit Scheduled to Issue: October 17, 2016
STATE CONTACT
If you have any questions on any of the above information or on the attached permit, please
contact Teresa Rodriguez at [phone].
f
NAME:
(:�( ln�, DATE:/ //(p

8/18/16 WQS = 12
Facility Name: Roxboro
otal Mercury 1631E PQL = 0.5 ng/L
Date Modifier Data
3/2/2010
3/16/2010
4/6/2010
4/20/2010'
5/4/2010
5/18/2010
6/3/2010
6/15/2010
7/6/2010
7/20/2010
8/3/2010
8/17/2010
9/7/2010
9/21/2010
10/5/2010
10/21/2010
11/2/2010
11/16/2010
12/7/2010
12/21/2010
1/4/2011
1/18/2011
2/2/2011
2/15/2011
3/1/2011
3/14/2011
4/5/2011
4/19/2011
5/3/2011
5/17/2011
6/7/2011
6/21/2011
7/6/2011
7/19/2011
8/2/2011
8/16/2011
5.96
4.97
4.19
3.61
3.8
3.36
7.63
3.67
2.75
1.7
1.32
2.33
1.52
1.99
2.28
6.42
5.14
3.51
2.05
3.18
4.25
4.85
6.11
6.92
6.71
6.33
4.24
2.91
3.35
5.69
4.7
4.71
2.32
1.44
2.88
2.71
ng/L
Value
5.96
4.97
4.19
3.61
3.8
3.36
7.63
3.67
2.75
1.7
1.32
2.33
1.52
1.99
2.28
6.42
5.14
3.51
2.05
3.18
4.25
4.85
6.11
6.92
6.71
6.33
4.24
2.91
3.35
5.69
4.7
4.71
2.32
1.44
2.88
2.71
MERCURY WQBEL/TBEL EVALUATION
No Limit Required
MMP Required
7Q10s = 0.000 cfs WQBEL =
Permitted Flow = 1109.000
V:2013-5
12.00 ng/L
47 niz/L
3.6 ng/L - Annual Average for 2010
4.4 ng/L - Annual Average for 2011

Duke Energy
NC0003425
Freshwater RPA -
Qw (MGD) = 0.25
1Q10S (cfs) = 0.00
7Q10S (cfs) = 0.00
7Q10W (cfs)= 0.00
30Q2 (cfs) = 0.00
Avg. Stream Flow, QA (cfs) = 0.00
Receiving Stream: NO HUC NUMBER
95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
WWTP/WTP Class: Roxboro
IWC% @ 1Q10S = 100
IWC% @ 7Q10S = 100
IWC%@ 7Q10W = 100
IWC% @ 30Q2 = 100
IW%C @ QA = 100
Stream Class: WS
Outfall Outfall 001 Seeps 9-14
Qw=0.25 MGD
COMBINED HARDNESS (mg/L)
Acute = 99 mg/L
Chromic = 99 mg/L
YOU HAVE DESIGNATED THIS RECEIVING
STREAM AS WATER SUPPLY
Effluent Hard:1 val > 100 mg/L 0 val < 25 mg/L
default 99 mg/L (Effluent Hard Med = 100 mg/L)
PARAMETER
STANDARDS & CRITERIA (2)
w
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
TYPE
(1)
NC WQS / Applied %2 FAV /
aR
z
n # Det. Max Pred Cw Allowable Cw
Chronic Standard Acute
Acute (FW): 340.0
Limit
Arsenic
C
150 FW 340
ug/L
_ _ _ _ _ ___
_________________________
3 3
76.2
Chronic (FW) 150.0
De 12RI It C. V.
Noval ue>Allowable Cw
Arsenic
C
10 HH/WS
ug/L
Note: it < 9
Chronic (HH) 10.0
Limited data set
2 value(s) > Allowable Cw
Acute: 6.690
Cadmium
NC
1.6678 TR 6.6897
ug/L
3 0 1 NO DETECTS
___ _ ____ _ ___
__________________________
Note: n < 9
Chronic: 1.668
Limited data set
Max MDL = 1
Acute: 2,793.8
Chromium III
NC
363.4201 FW 2793.8313
µg/L
0 0
N/A
___ _ ____ _ ___
__________________________
Chronic: 363.4
Acute: 16.0
Chromium VI
NC
11 FW 16
pg/L
0 0
N/A
___ _ _____ ___
__________________________
Chronic: 11.0
Chromium, Total
NC
µg/L
3 1 7.7
Monitor
Note: n<9 Default C.V
Limited data set
Acute: 38.30
Monitor
Copper
NC
25.5442 FW 38.2981
ug/L
3 2 13.26
_ _ _____ _ ___
_________________________
Note: n!5 9 Default C.V.
Chronic: 25.54
Limited data set
No value > Allowable Cw
Acute: NO WQS
limit
Fluoride
NC
1800 FW
ug/L
3 3 3,000.0
_ _ _ __ _ ___
_________________________
Note: n:5 9 Default C.V.
Chronic: 1,800.0
Limited dataset
No value> Allowable Cw
Acute: 347.352
Monitor
Lead
NC
13.5358 FW 347.3518
ug/L
3 1 6.270
___ _ ____ _ ___
__________________________
Note: Dct�.It C.A .
n <_ 9 u
Chronic: 13.536
Limited data set
No value> Allowable Cw
Acute: NO WQS
Monitor
Mercury
NC
12 FW
0.5
ng/L
3 0 1 NO DETECTS
___ _ _ ___ ___
_________________________
Note: n < 9
Chronic: 12.0
Limited data set
Max MDL = 1000
RPA seeps 09 14 (Autosaved).xlsm, rpa
Page 1 of 2 8/18/2016

Duke Energy Outfall Outfall 001 Seeps 9-14
NC0003425 Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators Qw = 0.25 MGD
RPA seeps 09 14 (Autosaved).xlsm, rpa
Page 2 of 2 8/18/2016
Acute: NO WQS
Molybdenum
NC
2000 HH
ug/L
3 3
330.0
1
_ _ _ — _ _ _
_ — — _ ——_—_—_—_—_—_—_—_
Note: n:5 9
Default C.V.
Chronic: 2,000.0
Limited data set
No value> Allowable Cw
Acute (FW): 1,073.9
Nickel
NC
119.2776 FW 1073.9039
Ng/[.
3 3
10.9
---------------------------------------------
Chronic (FW) 119.3
3te:n59
DelaultC.V.
N_ovalue >_Allow_able_Cw_
Nickel
NC
W's
25.0000 W
µg/L
. imited data set
C hronic (WS)_25.0
No value > Allowable Cw
Acute: 56.0
Limit
Selenium
NC
5 FW 56
ug/L
3 2
188.7
_ _
_ —_—_—_—_—_—_—_---_—_—_—
Note: n <9
Default C.V.
___ ----__
Chronic: 5.0
mited data sel
1 values > Allowable Cw
Acute: 403.4
Zinc
NC
406.7415 PN' 403.4414
ug/L
3 0 NO DETECTS
_ ___
_--_—_—_—_—_—_-----_—_—_—_
N nte: n 5 9
_
Chronic: 406.7
sited data set
Max MDL = 5
Acute:
0 0
N/A
--Chronic: ----------
---------------------------�
Acute:
0 0
NA
--------------------------
--Chronic:----------
Acute:
0 0
N
-— - — - — -—
Chronic:
------------------------
Acute:
0 0
NA
--------------------------
--Chronic:----------
RPA seeps 09 14 (Autosaved).xlsm, rpa
Page 2 of 2 8/18/2016

Table 1. P
Facility Name
WWTP/WTP Class
NPDES Permit
Outfall
Flow, Qw (MGD)
Receiving Stream
HUC Number
Stream Class
❑✓ Apply WS Hardness WQC
7Q10s (cfs)
7Q10w (cfs)
30Q2 (cfs)
QA (cfs)
1Q10s (cfs)
Effluent Hardness (Median)
Upstream Hardness
Combined Hardness Chronic
Combined Hardness Acute
Data Source(s) I
❑CHECK TO APPLY MODEL
Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
REQUIRED DATA ENTRY
ct Information
❑CHECK IF HQW OR ORW WQS I
i
Duke Energy
Roxboro
NC0003425
Outfall 001 Seeps 9-14
0.250
hyco lake
WS
0.00
0.00
0.00
0.00
- 0.00
default 99 mg/L (Effluent Hard Med = 100 mg/L)
99 mg/L (Average)
99mg/L -__---
99 mg/L �------
Par01
Par02
Par03
Par04
Par05
Par06N
Par07
Par08
Par09
Par10
Par11
Par12
L, Par13
Par14
Par15
Par16
Par17
Par18
Par19
Par20
Par21
Par22
Par23
Par24
Table 2. Parameters of Concern
Name WQS Type Chronic Modifier Acute PQL Units
Arsenic
Aquactic Life
C
150
FW
340
ug/L
Arsenic
Human Health Water Supply
C
10
HH/WS
N/A
ug/L
Beryllium
Aquatic Life
NC
6.5
FW
65
ug/L
Cadmium
Trout
NC
1.6678
TR
6.6897
ug/1-
g/LChlorides
Chlorides
Water Supply
NC
250
WS
mg/L.
Chlorinated Phenolic Compounds
Water Supply
NC
1
A
ug/L
Total Phenolic Compounds
Aquatic Life
NC
300
A
ug/L_
Chromium III
Aquatic Life
NC
363.4201
FW
2793.8313
ug/L
Chromium VI
Aquatic Life
NC
11
FW
16
pg/L
Chromium, Total
Aquatic Life
NC
N/A
FW
N/A
pg/L
Copper
Aquatic Life
FW
38.2981
ug/1-
Cyanide
Aquatic Life
NC
5
FW
22
10 ug/L
Fluoride
Aquatic Life
INC
1,800
FW
ug/L
Lead
Aquatic Life
NC
13.5358
FW
347.3518
ug/L
Mercury
Aquatic Life
NC
12
FW
0.5 nc,/L
Molybdenum
Human Health
NC
2000
HH
ug/L
Nickel
Aquatic Life
NC
119.2776
FW
1073.9039
pg/L
Nickel
Water Supply
INC
25.0000
WS
N/A
pg/L
Selenium
Aquatic Life
NC
5
FW
56
ug/L
Silver
Aquatic Life
NC
0.06
FW
3.1616
ug/L
Zinc
Aquatic Life
NC
406.7415
FW
403.4414
ug/L
RPA seeps 09 14 (Autosaved).xlsm, input
8/18/2016

RPA seeps 09 14 (Autosaved).xlsm, input
8/18/2016

H1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
REASONABLE POTENTIAL ANALYSIS
Effluent Hardness (monthly average)
Use "PASTE SPECIAL
Values" then "COPY"
Maximum data
H2
Upstream Hardness
Use "PASTE SPECIAL
Values" then "COPY"
. Maximum data
Par01 & Par02
Use "PASTE SF
Values" then
. Maximum
Arsenic
paints = 5
points = 58
points = 58
Date Data BDL=1/2DL Results
Date Data BDL=1/2DL Results
Date
Data BDL=1/2DL
Results
100 100 Std Dev.
N/A
1
100 100 Std Dev.
N/A
1
15.7 15.7
Std Dev.
11.8990
Mean
100.0000
2
Mean
100.0000
2
1.73 1.73
Mean
14.2767
C.V.
0.0000
3
C.V.
0.0000
3
25.4 25.4
C.V. (default)
0.6000
n
1
4
n
1
4
n
3
10th Per value
100.00 mg/L
5
10th Per value
100.00 mg/L
5
Median Value:
99.00 mg/L
6
Average Value
99.00 mg/L
6
Mult Factor =
3.00
Max. Value
100.00 mg/L
7
Max. Value
100.00 mg/L
7
Max. Value
25.4
8
8
Max. Pred Cw
76.2
9
9
10
10
11
11
12
12
13
13
14
14
15
15
16
16
RPA seeps 09 14 (Autosaved).xlsm, data
1 8/18/2016

REASONABLE POTENTIAL ANALYSIS
ParO4
Pall
Par10
Values" then "COP'
Copper
Values" then
Use"PASTE SPECIAL
. Maximum c
Cadmium
Values" then "COPY"
Chromium, Total
Date
1
Data BDL=1/2DL
< 1 0.5
. Maximum data
2.0639
1.1951
1.1900
2
1.34 1.34
Mean
points = 58
0.6000
3
4.42 4.42
Date
Data BDL=1/2DL
Results
4
Date
Data BDL=112DL
Results
1
< 1 0.5
Std Dev.
0.0000
1
3.00
1 0.5
Std Dev.
2
< 1 0.5
Mean
0.5000
2
Max. Value
1 0.5
Mean
3
< 1 0.5
C.V.
0.0000
3
9
2.57 2.57
C.V. (default)
4
n
3
4
n
5
5
6
13
Mult Factor =
1.00
6
Mult Factor =
7
Max. Value
0.500 ug/L
7
Max. Value
8
Max. Pred Cw
O DETECTS ug/L
8
Max. Pred Cw
9
9
10
10
11
11
12
12
13
13
14
14
15
15
16
16
Use "PASTE SPEC A&
Pall
Use "PASTE SF
Values" then "COP'
Copper
Values" then
. Maximum data
. Maximum c
points = 58
points = 5
Date
1
Data BDL=1/2DL
< 1 0.5
Results
Std Dev.
2.0639
1.1951
1.1900
2
1.34 1.34
Mean
2.0867
0.6000
3
4.42 4.42
C.V. (default)
0.6000
3
4
n
3
5
3.00
6
Mult Factor =
3.00
2.6 pg/L
7
Max. Value
4.42
7.7 pg/L
8
Max. Pred Cw
13.26
9
10
11
12
13
14
15
16
RPA seeps 09 14 (Autosaved).xlsm, data
-3- 8/18/2016

'ECTALPar13
-OPY"
lata
8
ug/L
ug/L
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
REASONABLE POTENTIAL ANALYSIS
-4-
Use"PASTE SPECIAL
Lead
Use"PASTE SPECIAL
Fluoride
Date Data BDL=1/2DL
Values" then "COPY"
1
< 1 0.5
. Maximum data
2
< 1 0.5
points = 58
Date Data BDL=1/2DL
Results
C.V. (default)
180 180
Std Dev.
413.2796
500 500
Mean
560.0000
1000 1000
C.V. (default)
0.6000
7
n
3
8
Mult Factor =
3.00
9
Max. Value
1000.0 ug/L
10
Max. Pred Cw
3000.0 ug/L
-4-
Use"PASTE SPECIAL
Lead
Date Data BDL=1/2DL
Results
1
< 1 0.5
Std Dev.
2
< 1 0.5
Mean
3
2.09 2.09
C.V. (default)
4
n
5
Results
0.9180
6
< 1000 500
Mult Factor =
7
2
Max. Value
8
0.6000
Max. Pred Cw
9
C.V.
3
10
n
11
5
12
3.00
6
13
Mult Factor =
2.090 ug/L
14
Max. Value
15
8
16
-4-
Use"PASTE SPECIAL
Values" then "COPY"
Mercury
. Maximum data
points = 58
Date Data BDL=1/2DL
Results
0.9180
1
< 1000 500
Std Dev.
1.0300
2
< 1000 500
Mean
0.6000
3
< 1000 500
C.V.
3
4
n
5
3.00
6
Mult Factor =
2.090 ug/L
7
Max. Value
6.270 ug/L
8
Max. Pred Cw
9
10
11
12
13
14
15
16
RPA seeps 09 14 (Autosaved).xlsm, data
8/18/2016

REASONABLE POTENTIAL ANALYSIS
Par16
Use "PASTE SPECIAL
Use"PASTE SPECIAL
Values" then "COPY"
Values" men "COPY"
. Maximum data
Molybdenum
Maximum data
points = 58
Data BDL=1/2DL
1.8129
1
1.86 1.86
Date
Data BDL=112DL
Results
0.0000
1
110 110
Std Dev.
500.0000
2
38.1 38.1
Mean
0.0000
3
106 106
C.V. (default)
3
4
n
8
5
9
1.00
6
10
Mult Factor =
500.0 ng/L
7
Max. Value
O DETECTS ng/L
8
Max. Pred Cw
9
14
10
16
11
12
13
14
15
16
REASONABLE POTENTIAL ANALYSIS
-5-
Par17 & Par18
Use "PASTE SPECIAL
Use"PASTE SPECIAL
Values" then "COPY"
Values- then "COPY"
. Maximum data
Nickel
. Maximum data
points = 58
Data BDL=1/2DL
1.8129
1
1.86 1.86
Date
Data BDL=112DL
Results
40.4063
1
< 1.0 0.5
Std Dev.
84.7000
2
< 1.0 0.5
Mean
0.6000
3
3.6 3.64
C.V. (default)
3
4
n
8
5
9
3.00
6
10
Mult Factor =
110.0 ug/L
7
Max. Value
330.0 ug/L
8
Max. Pred Cw
9
14
10
16
11
12
13
14
15
16
-5-
RPA seeps 09 14 (Autosaved).xlsm, data
8/18/2016
Par19
Use "PASTE SPECIAL
Values" then "COPY"
Selenium
. Maximum data
points = 58
Date
Data BDL=1/2DL
1.8129
1
1.86 1.86
1.5467
2
< 1 0.5
0.6000
3
62.9 62.9
3
4
5
3.00
6
3.6 pg/L
7
10.9 pg/L
8
9
10
11
12
13
14
15
16
RPA seeps 09 14 (Autosaved).xlsm, data
8/18/2016

REASONABLE POTENTIAL ANALYSIS
RPA seeps 09 14 (Autosaved).xlsm, data
- 6 - 8/18/2016
Par21
Use"PASTE SPECI
Use "PASTE SPECIAL
Values" then "COPY"
Zinc
Values" then "COPY"
. Maximum data
. Maximum data
points =58
'll nts.�.§8
Results
Date
Data BDL=1/2DL
Results
Std Dev.
35.6405
1
< 5 2.5
Std Dev.
0.0000
Mean
21.7533
2
< 5 2.5
Mean
2.5000
C.V.(default)
0.6000
3
< 5 2.5
C.V.
0.0000
n
3
4
n
3
5
Mutt Factor =
3.00
6
Mutt Factor =
1.00
Max. Value
62.9 ug/L
7
Max. Value
2.5 ug/L
Max. Pred Cw
188.7 ug/L
8
Max. Fred Cw
O DETECTS ug/L
9
10
11
12
13
14
15
16
RPA seeps 09 14 (Autosaved).xlsm, data
- 6 - 8/18/2016

NC0003425
Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
Qw (MGD) = 1.81 WWTP/WTP Class:
1Ql0S (cfs) = 0.00 IWC% @ 1Q10S = 100
7Q10S (cfs) = 0.00 IWC% @ 7Q10S = 100
7Q10W (cfs) = 0.00 IWC%@ 7Q10W = 100
30Q2 (cfs) = 0.00 IWC% @ 30Q2 = 100
Avg. Stream Flow, QA (cfs) = 0.00 IW%C @ QA = 100
Receiving Stream: NO HUC NUMBER Stream Class: WS
Outfall 006
Qw = 1.81 MGD
YOU HAVE DESIGNATED THIS RECEIVING
STREAM AS HQW OR ORW
COMBINED HARDNESS (me/L)
Acute = 25 mg/L
Chromic = 25 mg/L
YOU HAVE DESIGNATED THIS RECEIVING
STREAM AS WATER SUPPLY
Effluent Hard:O val > 100 mg/L 0 val < 25 mg/L
Effluent Hard Med = 25 mg/L
PARAMETER
STANDARDS 8 CRITERIA (2)
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
TYPE
(1)
J
a
zn
NC WQS / Applied %2 FAV /
Det Max Pred Cw Allowable Cw
Chronic Standard Acute
Acute: 28.0
Limited data, monitor quarterly
Selenium
NC
2.5 FW 2ti
ue I
1 1 5.4
_ _
etc: n59 Default C.V.-------_-----------_------
mited data • 1 values > Allowable Cw
Acute: 62.9
No RP
Zinc
NC
63.3667 FW 62.8526
ug/L
1 1 12.6
ote: n <_ 9 Deiault ('A.
Chronic: 63.4
=riled data set
No value > Allowable Cw
Acute:
0 0
N/A
---------------------------I
--Chronic:----------
Acute:
--Chronic: ----------
-------------------
Acute:
N,A
---------------------------------------------
Chronic:
Acute:
0 0
N
_
--Chronic:_ ----'-----
--------------------------
RPA 006.x1sm, rpa
Page 1 of 1 8/18/2016

Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
REQUIRED DATA ENTRY
Table 1. Project Information
Par01
Par02
Par03
Par04
Par05
Par06E
Par07
Par08
Par09
Par10
Par11
l' Par12
Par13
Par14
Par15
Par16
Par17
Par18
Par19
Par20
Par21
Par22
Par23
Par24
Table 2. Parameters of Concern
Name woS Type Chronic Modifier Acute PQL Units
Arsenic
Aquactic Life
❑� CHECK IF HQW OR ORW WQS
150
Facility Name
340
ug/L
Arsenic
Human Health Water Supply
WWTP/WTP Class
NPDES Permit
NC0003425
N/A
Outfall
006
Aquatic Life
Flow, Qw (MGD)
1.810
FW
Receiving Stream
Hyco Lake
Cadmium
Trout
NC
HUC Number
Stream Class
WS
ug/L
[2]Apply WS Hardness WQC
70111 Os (cfs)
0.00
250
7Q1 Ow (cfs)
30Q2 (cfs)
0.00
- --
0.00
mg/L.
QA (cfs)
0.00
i
1Q10s (cfs)
0.00
Effluent Hardness (Median)
4
25 mg/L
--default
Aquatic Life
Upstream Hardness
25 mg/L (Hard Aveage = 25 mg/L)
A
Combined Hardness Chronic
I _ , _ s _ 25 mg/L
Chromium III
Combined Hardness Acute
25 mg/L
117.7325
FW
0
Data Source(s)
❑CHECK TO APPLY MODEL
Aquatic Life
NC
11
Par01
Par02
Par03
Par04
Par05
Par06E
Par07
Par08
Par09
Par10
Par11
l' Par12
Par13
Par14
Par15
Par16
Par17
Par18
Par19
Par20
Par21
Par22
Par23
Par24
Table 2. Parameters of Concern
Name woS Type Chronic Modifier Acute PQL Units
Arsenic
Aquactic Life
C
150
FW
340
ug/L
Arsenic
Human Health Water Supply
C
10
HH/WS
N/A
ug/L
Beryllium
Aquatic Life
NC
6.5
FW
65
ug/L
Cadmium
Trout
NC
0.5899
TR
2.0145
ug/L
Chlorides
Water Supply
NC
250
WS
mg/L.
Chlorinated Phenolic Compounds
Water Supply
NC
1
A
ug/L
Total Phenolic Compounds
Aquatic Life
NC
300
A
ug/L
Chromium III
Aquatic Life
NC
117.7325
FW
905.0818
ug/L
Chromium VI
Aquatic Life
NC
11
FW
16
pg/L_
Chromium, Total
Aquatic Life
NC
N/A
FW
N/A
Ng/L
Copper
Aquatic Life
INC
7.8806
FW
10.4720
ug/L
Cyanide
Aquatic Life
NC
5
FW
22
10 ug/L
Fluoride
Aquatic Life
NC
1,800
FW
ug/L_
Lead
Aquatic Life
NC
2.9416
FW
75.4871
ug/L
Mercury
Aquatic Life
NC
12
FW
0.5 ng/L
Molybdenum
Human Healtn
NC
2000
HH
ug/L
Nickel
Aquatic Life
NC
37.2313
FW
335.2087
Ng/L
Nickel
Water Supply
NC
25.0000
WS
N/A
Ng/L
Selenium
Aquatic Life
NC
5
FW
56
ug/L
Silver
Aquatic Life
NC
0.06
FW
0.2964
ug/L
Zinc
Aquatic Life
INC
126.7335
FW
125.7052
ug/L
RPA 006.xlsm, input
8/18/2016

RPA 006.xism, input
8/18/2016

Par19
1
2
3
4
5
6
7
8
9
10
11
12
13
REASONABLE POTENTIAL ANALYSIS
Selenium
a "PASTE SPECIAL
Values" then "COPY"
Par21
. Maximum data
points = 58
Date Data BDL=1/2DL Results
5.4 5.4 Std Dev.
N/A
1
Mean
5.4000
2
C.V.
0.0000
3
n
1
4
5
Mull Factor =
1.00
6
Max. Value
5.4 ug/L
7
Max. Pred Cw
5.4 ug/L
8
9
10
11
12
13
Zinc
Date Data BDL=1/2DL Results
12.6 12.6 Std Dev.
Mean
C.V.
n
Mult Factor =
Max. Value
Max. Pred Cw
M
Use"PASTE SPECIAL
Values" then "COPY"
. Maximum data
points = 58
12.6000
0.0000
1
1.00
12.6 ug/L
12.6 ug/L
RPA 006.xism, data
8/18/2016

Roxboro Steam Electric Plant
NC0003425 Freshwater RPA - 95% Probability/95% Confidence Using Metal Translators
MAXIMUM DATA POINTS = 58
Qw (MGD) = 1109.00 WWTP/WTP Class:
1QIOS (cfs) = 0.00 lwco/ @ 1Q10S = 100
7Q10S (cfs) = 0.00 IWC°/ @ 7Q10S = 100
7QIOW (cfs) = 0.00 IWC% @ 7QIOW = 100
30Q2 (cfs) = 0.00 IWC% @ 30Q2 = 100
Avg. Stream Flow, QA (cfs) = 0.00 IW'/.0 @ QA = 100
Receiving Stream: NOHUCNUMBER Stream Class: WS
Outfall 003
Qw = 1109 MGD
COMBINED HARDNESS (me/L)
Acute = 99 mg/L
Chromic = 99 mg/L
YOU HAVE DESIGNATED THIS RECEIVING
STREAM AS WATER SUPPLY
Effluent Hard:1 val > 100 mg/L 0 val < 25 mg/L
default 99 mg/L (Effluent Hard Mea = 100 mg/L)
PARAMETER
STANDARDS & CRITERIA (2)
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
TYPE
J
F
NC WQS / Applied '/z FAV /
I n 4 Det. Max Pred Cw Allowable Cw
(1)
a
z
M
Chronic Standard Acute
Acute (FW): 340.0
Arsenic
C
150 FW 340
uW1,
No RP, > 50% of allowable. Monitor Quartedy
58 6
5.0
_ _ _
Chronic_(FW):----150.0 --
- -------------------
N_o value > Allowable Cw_
Arsenic
C
10 HH/WS
ug/L
Chronic (HH):-�--10.0 --
-----•-•- --- ------------
No value > Allowable Cw
NO WQS
Chlorides
Chlorides
INCNC
250 WS
250 WS
mg/L
'1911
36 35
16 11
114,1Acute:
134.1
No RP, > 50% of allowable. Monitor Quarterly.
.............................................
Chronic 250.0
No value > Allowable Cw
Acute: 38.30
Copper
NC
_>.,442 PW' 38.2_981
ug/L
36 0
NO DETECTS
No RP
_ _ _ _-_-_ _
Chronic: 25.54
-_-_-_-_-_-_-_-___-_-
Max MDL = 5
Acute (FW): 1,073.9
Nickel
NC
119.2776 FIV 1073.9039
µg2
No RP
36 36
1.5
Chronic (FW) ----119.3 --
-------------------------
No value >_ Allowable Cw
Nickel
NC
25.0000 WS
µg/L
Chronic (WS): 25.0
No value> Allowable Cw
Acute: 56.0
Selenium
NC
5 FW 56
ug/L
36 36
4.1
-----------------------------
No RP, > 50% of allowable. Monitor Quarterly
Chronic: 5.0
-----------•-----
No value > Allowable Cw
Acute: 403.4
Zinc
INC
406.7415 FW 403.4414
ug/L
36 7
113.4
No RP
--------------------------------------------- _ _ _ _ _
_Chronic: _-_-_-
406.7
-_-_-_-_-_-_-_-.-_-_-_-_-_-
No value> Allowable Cw
Acute: NO WQS
thallium
INC
0.24 WS
µg2
36 1
0.28500
RP, one detection at MDL
------------------------------
Chronic: 0.24000
______
1 value(s) > Allowable Cw
Monitor quarterlly
Acute: NO WQS
Strontium
NC
14000 WS
µg2
36 36
271.36000
No RP
_ __ _ _ _ _
--Chronic: 14000.00000
---_----- ...............
No value> Allowable Cw
Acute:
0 0
N/A
- _ _ _-_-_-_-_-
Chronic:
_ _-_-_-_-_-_-_-_-
Acute:
0 0
N/A
___ _ _____
Chronic
_
Page 1 of i RPA Outfall 003.xlsm, rips
8/18/2016