NC0003425_Draft Permit_20210309

Y
ROY COOPER 'I r' _
Governor
MICHAEL S.REGAN
Secretary
S.DANIEL SMITH NORTH CAROLINA
Director Environmental Quality
March 9, 2021
Mr. Paul Draovitch, Senior Vice President
Environmental, Health and Safety
Duke Energy Carolinas,LLC
Mail Code EC13K
P.O. Box 1006
Charlotte,North Carolina 28201-1006
Subject: Draft NPDES Major Modification
Permit NC0003425
Roxboro Steam Electric Generating Plant
Person County
Facility Class I
Dear Mr. Draovitch:
The Division has received your request for a Major Modification of the subject permit.
Enclosed with this letter is the modified permit. Please review this permit modification carefully to
ensure thorough understanding of the conditions and requirements it contains.
The draft permit modification contains the following significant changes from your current
permit:
1). The bottom ash purge water was added to the list of the contributing sources of wastewater to
the Lined Retention Basin. Per updated 40 CFR 423.13(k)(2)(i)(A) (updated on 10/13/2020), the
discharge of pollutants in bottom ash transport water from a properly installed, operated, and
maintained bottom ash system is authorized to maintain system water chemistry where installed
equipment at the facility is unable to manage pH, corrosive substances, substances or conditions
causing scaling,or fine particulates to below levels which impact system operation or maintenance.
2). The Technology Based Effluent Limits for Total Arsenic, Total Mercury, Total Selenium, and
Nitrate/nitrite as N were adjusted for Internal Outfall 010 and Internal Outfall 011 (FGD
wastewater) in accordance with updated 40 CFR 423.13(g)(1)(i).
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3). The flow limit for the Internal Outfall 002 was increased from 2.0 MGD to 3.0 MGD to
accommodate large storm events. In addition, the interstitial flow volume reporting was added
to this outfall.
4).The header for the Condition A.(1)was corrected to allow for the complete ash excavation from
the East Ash Basin Extension and for the discharge of industrial stormwater from the landfill.
5).The monthly instream monitoring location name was changed from 6B to F2(Special Condition
A. (18)).
Please provide any comments you have regarding the draft permit modification to this
office by April 12, 2021. At this time, the Division is also publishing a notice in the newspapers of
general circulation in Person County,inviting public comment on the Draft Modification. Following
the 30-day comment period,we will review all pertinent comments received and take appropriate action
on the permit modification.
If you have any questions about the NPDES permit process,please contact me at the
following e-mail address: sergei.chernikov(a,ncdenr.gov,or telephone number: 919-707-3606.
Sincerely,
Sergei Chernikov,Ph.D.
Environmental Engineer III
Industrial NPDES Permitting Unit
cc: Central Files
NPDES Files
EPA Region IV (e-copy)
Raleigh Regional Office/Water Quality (e-copy)
Raleigh Regional Office/PWS (e-copy)
WSS/Aquatic Toxicology Unit (e-copy)

Permit NC0003425
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WATER RESOURCES
Draft PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provisions of North Carolina General Statute 143-215.1,other lawful
standards and regulations promulgated and adopted by the North Carolina Environmental
Management Commission, and the Federal Water Pollution Control Act,as amended,
Duke Energy Progress, LLC
is hereby authorized to discharge wastewater from a facility located at the
Roxboro Steam Electric Generating Plant
1700 Dunnaway Road,Semora
Person County
to receiving waters designated as Hyco Reservoir in the Roanoke River Basin in accordance with
effluent limitations,monitoring requirements, and other applicable conditions set forth in Parts I,
II, III and IV hereof.
This permit shall become effective
This permit and the authorization to discharge shall expire at midnight on June 30,2025.
Signed this day
S. Daniel Smith,Director
Division of Water Resources
By Authority of the Environmental Management Commission
Page 1 of 29

Permit NC0003425
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility,whether for operation or discharge are hereby revoked.As of this
permit issuance,any previously issued permit bearing this number is no longer effective.Therefore,the exclusive
authority to operate and discharge from this facility arises under the permit conditions,requirements,terms,and
provisions included herein.
Duke Energy Progress,LLC is hereby authorized to:
1. Continue to operate the following systems located at Roxboro Steam Electric Generating Plant off
NCSR 1377 near Roxboro in Person County:
• Outfall 001.Discharge overflow from the East Ash Basin Extension,extracted groundwater,ash
basin closure flows,and stormwater runoff into a UT to Hyco Reservoir.
• Ash Pond Treatment System(Internal Outfall 002). Continue to discharge ash transport water,low
volume wastewater,runoff from the ash landfill,dry fly ash handling system wash water,ash silo
wash water,storm water runoff,cooling tower blowdown from unit number 4,and domestic
sewage treatment plant effluent. Effluent from the ash pond discharges through an internal
conveyance to the heated discharge pond,and is ultimately released into Hyco Reservoir through
Outfall 003.
• Heated Discharge Pond(Outfall 003). Continue to discharge once-through cooling water,
stormwater runoff,coal pile runoff,flue gas desulfurization treated wastewater,flue gas
desulfurization cooling water,ash pond dam chimney drains and other basin seepage flows,
anhydrous ammonia testing waters and emergency flows(until construction of low volume wastes
treatment system),effluent from the ash pond(Outfall 002),ash basin closure flows,and extracted
groundwater. Continue to discharge the effluent from the low volume waste treatment systems
(Outfall 012A and 012B),and yard sump overflow to the heated discharge pond.This outfall
discharges to Hyco Reservoir.
• Cooling Tower Blowdown System(Internal Outfall 005). Continue to discharge cooling tower
blowdown from unit number 4 into the low volume wastewater treatment system(outfall 012B)or
into the heated discharge pond.
• Coal Pile Runoff Treatment System(Outfall 006). Emergency overflow from the coal pile and
other coal handling areas,runoff from the limestone and emergency gypsum stack,raw water tank
drainage,incidental leakage from absorbent seals,and the truck wheel wash water. On a non-
emergency basis these waters are routed to a retention pond for treatment by neutralization,
sedimentation,and equalization prior to being discharged directly into Hyco Reservoir.
• Domestic Wastewater Treatment System(Internal Outfall 008). Continue to discharge effluent
from the domestic treatment system into the ash pond or the low volume waste treatment system
(Outfall 012B).
• Chemical Metal Cleaning Treatment System(Internal Outfall 009). Continue to discharge
chemical metal cleaning wastes into the low volume waste treatment system(Outfall 012).
• Flue Gas Desulfurization Treatment System(Internal Outfall 010).Continue to operate a FGD wet
scrubber treatment system consisting a settling pond and a bioreactor,discharging into the heated
discharge pond.
• Flue Gas Desulfurization Treatment System(Internal Outfall 011).Upon completion of
construction,operate a Flue Gas Desulfurization System discharging to the low volume waste
treatment system(outfall 012B)or the heated discharge pond.
• Low Volume Wastes Treatment System(Internal Outfall 012A).Upon construction,discharge
landfill stormwater,east ash basin closure flows,treated extracted groundwater,contact and non-
contact storm water runoff into the heated discharge pond.
• Lined Retention Basin(Internal Outfall 012B).Continue to discharge low volume wastes,metal
cleaning wastes(Internal Outfall 009),ash silo wash water,cooling water from Unit 4,anhydrous
ammonia testing waters and emergency flows,domestic sewage treatment plant effluent,domestic
WWTP effluent(Internal Outfall 008),bottom ash purge from the submerged flight conveyers
(purge volume not to exceed 10% of the water systems volume), ash landfill leachate,treated FGD
Page 2 of 29

Permit NC0003425
blowdown,storm water runoff,runoff from the coal pile and other coal handling areas,runoff from
the limestone and emergency gypsum stack,raw water tank drainage,incidental leakage from
absorbent seals,and the truck wheel wash water. These waters are routed to a retention pond for
treatment by neutralization,sedimentation,and equalization prior to being discharged to retention
basin.The retention basin discharges into the heated discharge pond.
■ Emergency overflow from low volume wastewater treatment system(Outfall 012C).Continue to
discharge emergency overflow from retention basin to Hyco Reservoir.
2. Discharge from said treatment works and/or outfalls at the locations specified on the attached map
into the Hyco Reservoir,classified as WS-V&B waters in the Roanoke River Basin.
Page 3 of 29

Permit NC0003425
Part I
A. (1)Effluent Limitations and Monitoring Requirements(Outfall 001) [15A NCAC 02B.0400 et seq.,
02B.0500 et seq.]
During the period beginning on the effective date of this permit and lasting until expiration,the Permittee
is authorized to discharge from Outfall 001 (overflow from East Ash Basin Extension,and stormwater
runoff).Such discharges shall be limited and monitored!by the Permittee as specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
CHARACTERISTICS Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location
Flow,MGD Weekly Estimate Effluent
pH 6.0 to 9.0 S.U. Monthly Grab Effluent
TSS 30.0 mg/L 100.0 mg/L Monthly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Monthly Grab Effluent
Fluoride 1.8 mg/L 1.8 mg/L Monthly/Weekly2 Grab Effluent
Total Arsenic,µg/L 10.0 µg/L 340.0 µg/L Monthly/Weekly2 Grab Effluent
Total Copper,µg/L Monthly/Weekly2 Grab Effluent
Total Antimony,µg/1 Monthly/Weekly2 Grab Effluent
Total Lead,µg/L Monthly/Weekly2 Grab Effluent
Total Selenium 5.0 µg/L 56.0 µg/L Monthly/Weekly2 Grab Effluent
Total Barium,mg/L Monthly/Weekly2 Grab Effluent
Total Iron,µg/L Monthly/Weekly2 Grab Effluent
Total Manganese,µg/L Monthly/Weekly2 Grab Effluent
Total Zinc,µg/L Monthly/Weekly2 Grab Effluent
Total Nickel,µg/L Monthly/Weekly2 Grab Effluent
Total Mercury,ng/L3 Monthly/Weekly2 Grab Effluent
Chlorides,mg/L Monthly/Weekly2 Grab Effluent
Nitrate/Nitrite as N Monthly Grab Effluent
Sulfates Monthly Grab Effluent
Total Dissolved Solids, Monthly Grab Effluent
mg/L
Hardness-Total as Quarterly Grab Effluent
[CaCO3 or(Ca+Mg)] mg/L
Acute Toxicity! Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A. (29).
2. The facility shall conduct weekly sampling during removal of the ash from the east ash basin
extension.
3. The facility shall use EPA method 1631E.
4. Acute Toxicity(Pimephales promelas,24-hour)monitoring shall be performed in accordance with
Special Condition A. (14)of this permit.
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Within 180 days of the issuance date of the permit the permittee shall submit Items V and VI of NPDES
application Form 2C.
If any one of the pollutants(As,Se,Hg,Ni,and Pb)reaches 85% of the allowable level during the
decanting/dewatering,the facility shall immediately discontinue discharge of the wastewater and report
it to the Regional Office and Complex NPDES Permitting Branch via telephone and e-mail.
Page 4 of 29

Permit NC0003425
A.(2)Effluent Limitations and Monitoring Requirements(Outfall 002-normal operation- decanting
phase) [15A NCAC 02B.0400 et seq.,02B.0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration or
commencement of the dewatering operations,the Permittee is authorized to discharge from Internal
Outfall 002 ash pond effluent(decanting the free water above the settled ash layer that does not
involve mechanical disturbance of the ash). Such discharges shall be limited and monitored.'by the
Permittee as specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
CHARACTERISTICS Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location
Flow Daily Continuous Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L 2/Month Grab Effluent
Total Suspended Solids3 30.0 mg/L 100 mg/L 2/Month Grab Effluent
Total Arsenic,µg/L Weekly Grab Effluent
Total Molybdenum,µg/L Weekly Grab Effluent
Total Selenium,µg/L Weekly Grab Effluent
pH4 Monthly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system See Special Condition A.(29).
2. Samples taken in compliance with the monitoring requirements listed above shall be taken at the ash
pond discharge prior to mixing with other sources of wastewater.
3. The facility shall continuously monitor TSS concentration when the decanting process commences and
the pump is operating.The dewatering pump shall be shutoff automatically when one half of the
Daily Maximum limit(15 minutes average)is exceeded.Pumping will be allowed to continue if
interruption might result in a dam failure or damage.Continuous TSS monitoring is only required
when pumps are employed for decanting.
4. The facility shall continuously monitor pH when the decanting process commences and the decanting
pump shall be shutoff automatically when 15 minutes running average pH falls below 6.1 standard
units or rises above 8.9 standard units.Pumping will be allowed to continue if interruption might
result in a dam failure or damage.Continuous pH monitoring is only required when pumps are
employed for decanting.
By April 30,2021 there shall be no discharge of pollutants in bottom ash transport waters.This
requirement only applies to bottom ash transport water generated after April 30,2021.
In accordance with N.C.G.S.§130A-309.210,by December 31,2019,the facility shall convert to the
disposal of dry bottom ash,as defined in the Coal Ash Management Act("CAMA").
Fly ash is handled dry at this facility.
The facility is allowed to draw down the wastewater in the ash pond to no less than three feet above the
ash.
The limits and conditions in Section A.(3)of the permit apply when water in the ash settling basin is
lowered below the three feet trigger mark,measured at the pump intake.
The rate for lowering the liquid level in a coal ash pond shall not exceed one(1)foot per day unless a
higher rate is supported to the satisfaction of DEMLR and in accordance with NCAC,Title 15A,
Subchapter 2K.
Page 5 of 29

Permit NC0003425
The facility shall use a floating pump station with free water skimmed from the basin surface using an
adjustable weir.
The facility shall notify via e-mail DWR Complex NPDES Permitting Unit and DWR Raleigh Regional
Office seven calendar days prior to the commencement of the dewatering.
When the facility commences the ash pond decanting/dewatering,the facility shall treat the wastewater
discharged from the ash pond using physical-chemical treatment,if necessary,to assure state Water
Quality Standards are not contravened in the receiving stream.Duke Energy shall notify DWR NPDES
Permitting and DWR Raleigh Regional Office,in writing,within seven calendar days of installing
additional physical-chemical treatment at this Outfall.
•
Page 6 of 29

Permit NC0003425
A. (3)Effluent Limitations and Monitoring Requirements (Outfall 002-dewatering phase) [15A NCAC
02B.0400 et seq.,02B.0500 et seq.]
During the period beginning upon the commencement of the dewatering operations and lasting until
expiration,the Permittee is authorized to discharge from Internal Outfall 002(Ash Pond Treatment
System Dewatering-removing the interstitial water). Such discharges shall be limited and monitored)
by the Permittee as specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
CHARACTERISTICS Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location2
Flow,MGD Weekly Continuous Effluent
Interstitial Flow 3.0 MGD Weekly Continuous Effluent
Total Selenium,µg/L Weekly Grab Effluent
Total Arsenic,µg/L Weekly Grab Effluent
Total Mercury,ng/L Weekly Grab Effluent
Total Molybdenum,µg/L Weekly Grab Effluent
Total Antimony,µg/L Weekly Grab Effluent
Total Copper,µg/L Weekly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Weekly Grab Effluent
Total Suspended Solids3 30.0 mg/L 100 mg/L Weekly Grab Effluent
pH4 Monthly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A. (29).
2. Effluent sampling shall be conducted at the discharge from the ash settling pond prior to mixing
with any other waste stream.
3. The facility shall continuously monitor TSS concentration when the dewatering process commences
and the pump is operating.The dewatering pump shall be shutoff automatically when one half of the
Daily Maximum limit(15 minutes average)is exceeded.Pumping will be allowed to continue if
interruption might result in a dam failure or damage.The continuous TSS monitoring only required
when the pumps are employed for dewatering.
4. The facility shall continuously monitor pH when the dewatering process commences and the
dewatering pump shall be shutoff automatically when the 15 minutes running average pH falls below
6.1 standard units or rises above 8.9 standard units.Pumping will be allowed to continue if
interruption might result in a dam failure or damage.The continuous pH monitoring only required
when the pumps are employed for dewatering.
There shall be no discharge of floating solids or visible foam in other than trace amounts.
By April 30,2021 there shall be no discharge of pollutants in bottom ash transport waters.This
requirement only applies to fly ash transport water generated after April 30,2021.
In accordance with N.C.G.S. §130A-309.210,by December 31,2019,the facility shall convert to the
disposal of dry bottom ash,as defined in the Coal Ash Management Act("CAMA").
Fly ash is dry handled at this facility.
The rate for lowering the liquid level in a coal ash pond shall not exceed one(1)foot per day unless a
higher rate is supported to the satisfaction of DEMLR and in accordance with NCAC,Title 15A,
Subchapter 2K.
Page 7 of 29

Permit NC0003425
The facility shall notify via e-mail DWR Complex NPDES Permitting Unit and DWR Raleigh Regional
Office seven calendar days prior to the commencement of the dewatering.
When the facility commences the ash pond decanting/dewatering,the facility shall treat the wastewater
discharged from the ash pond using physical-chemical treatment,if necessary,to assure state Water
Quality Standards are not contravened in the receiving stream.Duke Energy shall notify DWR NPDES
Permitting and DWR Raleigh Regional Office,in writing,within seven calendar days of installing
additional physical-chemical treatment at this Outfall.
Page 8 of 29

Permit NC0003425
A. (4)Effluent Limitations and Monitoring Requirements(Outfall 003) [15A NCAC 02B .0400 et seq.,
02B.0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration,the Permittee
is authorized to discharge from Outfall 003(Heated Discharge Pond to the Hyco Reservoir). Such
discharges shall be limited and monitored)by the Permittee as specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
CHARACTERISTICS Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location2
Flow Daily Calculation Effluent
Total Residual Chlorine3 28 µg/L 2/Month Grab Effluent
Total Phosphorus Monthly Grab Effluent
Total Nitrogen Monthly Grab Effluent
Effluent,
Temperature 4 Continuous Recorder Afterbay
Discharge
Total Arsenic,µg/L Monthly/Weekly5 Grab Effluent
Total Selenium,µg/L Monthly/Weekly5 Grab Effluent
Chloride,mg/L Monthly/Weekly5 Grab Effluent
Total Mercury,ng/L6 Monthly/Weekly5 Grab Effluent
Total Antimony,µg/L Monthly/Weekly5 Grab Effluent
Total Molybdenum,µg/L Monthly/Weekly5 Grab Effluent
Total Thallium µg/L Monthly/Weekly5 Grab Effluent
pH 6.0 to 9.0 S.U. Monthly/Weekly5 Grab Effluent
Ammonia? 1.0 mg/L 5.0 mg/L Daily? Grab Effluent
Acute Toxicity8 Quarterly Composite Effluent
Hardness-Total as
[CaCO3 or(Ca+Mg)], Quarterly Grab Effluent,4C 4D
mg/L
Turbidity9,NTU Monthly/Weekly5 Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A.(29).
2. Effluent sampling shall be performed in the heated discharge pond at the point of discharge into Hyco
Reservoir.
3. Total Residual Chlorine compliance(including monitoring)is required only if chlorine or chlorine
derivative is added to the cooling water. The Division shall consider all effluent TRC values reported
below 50 µg/L to be in compliance with the permit. However,the permittee shall continue to record
and submit all values reported by a North Carolina certified laboratory(including field certified),even
if these values fall below 50 µg/L.
4. The Permittee shall operate so as to remain in compliance with the conditions outlined in the mixing
zone defined in Special Condition A. (17)of this permit. The temperature of Hyco Reservoir at no
time shall exceed the thermal water quality standard outside the mixing zone defined in Special
Condition A.(17).These thermal limitations may be deleted or revised,as appropriate,based upon
evaluation of the results of the thermal studies.This permit may be reopened to implement a
temperature limit if the permittee is not in compliance with Special Condition A.(17).
5. The facility shall conduct weekly sampling during dewatering of the ash basin.
6. The facility shall use EPA method 1631E.
7. Ammonia limit and monitoring is only applicable in the event of an emergency release of anhydrous
ammonia during the time the released waters are discharged through outfall 003.
Page 9 of 29

Permit NC0003425
8. Acute Toxicity(Pimephales promelas)P/F @ 90%,March,June,September and December. See Special
Condition A. (14)of this permit. Composite samples for this effluent characteristic shall consist of 24
or more grab samples of equal volumes collected at equal intervals over a 24-hour period.
9. The net turbidity shall not exceed 50 NTU using a grab sample and measured by the difference
between the effluent turbidity and the background turbidity.The sample for the background turbidity
shall be taken at a point in the receiving waterbody upstream of the discharge location,and the
background turbidity and the effluent turbidity samples shall be taken within the same 24 hour
period.
NTU-Nephelometric Turbidity Unit
The Permittee is allowed to operate Unit 3 in a once-through cooling mode from October 15 through April
30.
If any one of the pollutants(As,Se,and Hg)reaches 85% of the allowable level during the
decanting/dewatering,the facility shall immediately discontinue discharge of the wastewater and report
it to the Regional Office and Complex NPDES Permitting Branch via telephone and e-mail.
There shall be no discharge of floating solids or visible foam in other than trace amounts outside a distance
five(5)meters from the discharge pipe.
Page 10 of 29

Permit NC0003425
A. (5)Effluent Limitations and Monitoring Requirements (Internal Outfall 005) [15A NCAC 02B .0400
et seq.,02B.0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration,the Permittee
is authorized to discharge from Internal Outfall 005(Cooling Tower Blowdown). Such discharges shall
be limited and monitored)by the Permittee as specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample
CHARACTERISTICS Average Maximum Frequency Sample Type Location2
Flow Continuous Pump Logs Effluent
during discharge
Free Available Chlorin& 200 µg/L 500 µg/L 2/month Multiple Grabs Effluent
Total Residual Chlorin& Monthly Multiple Grabs Effluent
Total Chromium4 200 µg/L 200 µg/L 2/Month Composite Effluent
Total Zinc4 1.0 mg/L 1.0 mg/L 2/Month Composite Effluent
The 126 Priority Pollutants(40
CFR Part 423,Appendix A)
Exclusive of Zinc and No Detectable Amount Annual Grab Effluent
Chromium4
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A. (29).
2. Effluent sampling shall be conducted at the discharge from the cooling tower prior to mixing with
other waste streams.
3. Neither free available chlorine nor total residual chorine may be discharged from any single
generating unit for more than two hours per day,unless the Permittee demonstrates to the Division
that discharge for more than two hours is required for macroinvertebrate control. The 500 µg/L is a
daily maximum limitation and is to be measured during the chlorine release period. The 200 µg/L
limitation is an average during the chlorine release period. Monitoring is required only when chlorine
is added to the cooling water system.
4. Limitations and monitoring requirements for the 126 Priority Pollutants(per 40 CFR Part 423,
Appendix A,exclusive of zinc and chromium)apply only if these substances are added by the
permittee for cooling tower maintenance. Compliance with the limitations for the 126 priority
pollutants in 40 CFR 423.13(d)(1)may be determined by engineering calculations which demonstrate
that the regulated pollutants are not detectable in the final discharge by the analytical methods in 40
CFR Part 136. All primary industries are required to submit a priority pollutant analysis in accordance
with 40 CFR Part 122 with their application for permit renewal.
Discharge of blowdown from the cooling tower is defined as the minimum discharge of recirculation
water necessary for the purpose of discharging materials contained in the process,the further build-up of
which would cause concentration in amounts exceeding limitations established by best engineering
practice.
The Permittee is authorized to discharge Maintenance Drain wastewater from the Cooling Tower for Unit
4 directly to the discharge canal. Grab samples of the following parameters are to be collected prior to
mixing with other waste streams and the results shall be submitted to DWR:pH(SU),flow(MGD)and
total residual chlorine(mg/L). The Permittee shall notify the Division of Water Resources,Raleigh
Regional Office,prior to draining the cooling tower,except during non-office hour emergencies when
notification must be made the next working day.Total residual chlorine monitoring is required prior to a
maintenance drain of the Unit 4 Cooling Tower only if chlorine is added to the system.
Page 11 of 29

Permit NC0003425
A. (6)Effluent Limitations and Monitoring Requirements(Outfall 006) [15A NCAC 02B.0400 et seq.,
02B .0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration,the Permittee
is authorized to discharge from Outfall 006(Coal Pile Runoff Treatment System to the Hyco Reservoir).
Such discharges shall be limited and monitored"by the Permittee as specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
CHARACTERISTICS Monthly Daily Measurement Sample Type Sample Location3
Average Maximum Frequency2 p yP P
Flow Monthly Estimate Effluent
Total Suspended Solids 50.0 mg/L Monthly Grab Effluent
Total Selenium 56.0 µg/L Monthly Grab Effluent
Oil and Grease 20.0 mg/L _ Monthly Grab Effluent
pH 6.0 to 9.0 S.U. Monthly Grab Effluent
Acute Toxicity' Annually Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A. (29).
2. The permittee shall collect samples if the pond discharges during a calendar month.If there is no
discharge during the calendar month"No Flow" shall be denoted in the DMR.
3. Effluent sampling shall be conducted at the point of discharge into Hyco Reservoir. Samples taken in
compliance with the monitoring requirements listed above shall be taken prior to mixing with other
sources of wastewater.
4. Acute Toxicity(Pimephales promelas,24-hour)monitoring shall be performed in accordance with
Special Condition A. (15)of this permit.
There shall be no discharge of floating solids or visible foam in other than trace amounts outside a distance
five(5)meters from the discharge pipe.
Material storage runoff shall include rainfall to navigable waters through any discernable,confined
and/or discrete conveyance from,or through,coal.
Within 180 days of the effective date of the permit,the permittee shall submit Items V and VI of NPDES
application Form 2C.
Page 12 of 29

Permit NC0003425
A. (7)Effluent Limitations and Monitoring Requirements (Internal Outfall 008) [15A NCAC 02B .0400
et seq.,02B.0500 et seq.]
During the period beginning upon the effective date of the permit and lasting until expiration,the
Permittee is authorized to discharge from Internal Outfall 008(Domestic Wastewater Treatment System)
into the low volume waste treatment system. Such discharges shall be limited and monitored)by the
Permittee as specified below:
EFFLUENT DAILY MAXIMUM MONITORING REQUIREMENTS
Monthly Daily Measurement Sample
CHARACTERISTICS Average Maximum Frequency Sample Type Location2
Flow 0.025 MGD Quarterly/Annual3 Pump Logs Effluent
Biochemical Oxygen 3
Demand(5-day®20°C) 30.0 mg/L 45.0 mg/L Quarterly/Annual Grab Effluent
Total Suspended Solids 30.0 mg/L 45.0 mg/L Quarterly/Annual3 Grab Effluent
Total Ammonia(as N) Quarterly/Annual3 Grab Effluent
pH Quarterly/Annual3 Grab Effluent
Fecal Coliform 200/100 mL 400/100 mL Quarterly/Annual3 Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A.(29).
2. Samples taken in compliance with the monitoring requirements listed above shall be taken after
treatment and prior to mixing with other sources of wastewater.
3. After one year of quarterly monitoring the sampling frequency will be modified to Annual.
See Special Condition A. (22).
Page 13 of 29

Permit NC0003425
A. (8) Effluent Limitations and Monitoring Requirements (Internal Outfall 009) [15A NCAC 02B .0400
et seq.,02B.0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration,the Permittee
is authorized to discharge from Internal Outfall 009(Metal Cleaning Wastes). Such discharges shall be
limited and monitored)by the Permittee as specified below:
LIMITS MONITORING REQUIREMENTS
EFFLUENT
CHARACTERISTICS Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location
Once per Discharge Pump Logs
Floe Event or similar Outfall 012B
reading
Total Suspended Solids 30.0 mg/L 100 mg/L Once per Discharge Grab Outfall 012B
Event
Oil and Grease 15.0 mg/L 20.0 mg/L Once per Discharge Grab Outfall 012B
Event
Once per Discharge
Total Copper 1.0 mg/L 1.0 mg/L pp g/ g/ Grab Outfall 012BEvent
Total Iron 1.0 mg/L 1.0 mg/L Once per Discharge Grab Outfall 012B
Event
pH Once per Discharge Grab Outfall 012B
Event
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A. (29).
2. Samples taken in compliance with the monitoring requirements listed above shall be taken prior to
mixing with other sources of wastewater.
Page 14 of 29

Permit NC0003425
A. (9) Effluent Limitations and Monitoring Requirements(Internal Outfall 010) [15A NCAC 02B.0400
et seq.,02B.0500 et seq.]
During the period beginning on the effective date of the permit and lasting until the existing FGD
treatment system is decommissioned,the Permittee is authorized to discharge from Internal Outfall 010
(FGD blowdown). Such discharges shall be limited and monitoredi by the Permittee as specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample
CHARACTERISTICS Average Maximum Frequency Sample Type Location2
Flow Pump Logs or
Monthly Effluent
similar reading
Total Suspended Solids 30.0 mg/L 100.0 mg/L Quarterly Grab Effluent
Oil and grease 15.0 mg/L 20.0 mg/L Quarterly Grab Effluent
Total Arsenic3 8.0 pg/L 18.0 pg/L Quarterly Grab Effluent
Total Mercury3 34.0 ng/L 103.0 ng/L Quarterly Grab Effluent
Total Selenium3 29.0 pg/L 70.0 pg/L Quarterly Grab Effluent
Nitrate/Nitrite as N3 3.0 mg/L 4.0 mg/L Quarterly Grab Effluent
pH Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.Special Condition A. (29).
2. Samples taken in compliance with the monitoring requirements listed above shall be taken after
bioreactor treatment and prior to mixing with other sources of wastewater.
3. In accord with the Steam Electric Effluent Limitations Guidelines for FGD wastewater(40 C.F.R.
423),these limits shall become effective on December 31,2021. This permit may be reopened and
modified if changes are made to 40 C.F.R.423.
There shall be no discharge of untreated FGD blowdown.
Page 15 of 29

Permit NC0003425
A.(10)Effluent Limitations and Monitoring Requirements (Internal Outfall 011) [15A NCAC 02B .0400
et seq.,02B.0500 et seq.]
During the period beginning upon the commencement of operations of the new FGD system and lasting
until expiration,the Permittee is authorized to discharge from Internal Outfall 011(FGD blowdown).
Such discharges shall be limited and monitored)by the Permittee as specified below:
LIMITS MONITORING REQUIREMENTS
EFFLUENT Monthly Daily Measurement Sample
CHARACTERISTICS Average Maximum Frequency Sample Type Location
Flow PumMonthly similar Logs
Effluentsimilar
Total Suspended Solids 30.0 mg/L 100.0 mg/L Quarterly Grab Effluent
Oil and grease 15.0 mg/L _ 20.0 mg/L Quarterly Grab Effluent
Total Arsenic 3 8.0 pg/L 18.0 µg/L Quarterly Garb Effluent
Total Mercury 3 34.0 ng/L 103.0 ng/L Quarterly Grab Effluent
Total Selenium 3 29.0 pg/L 70.0 pg/L Quarterly Grab Effluent
Nitrate/Nitrite as N 3 3.0 mg/L 4.0 mg/L Quarterly Grab Effluent
pH Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A. (29).
2. Samples taken in compliance with the monitoring requirements listed above shall be taken after
bioreactor treatment and prior to mixing with other sources of wastewater.
3. In accord with the Steam Electric Effluent Limitations Guidelines for FGD wastewater(40 C.F.R.
423),these limits shall become effective on December 31,2021. This permit may be reopened and
modified if changes are made to 40 C.F.R.423.
There shall be no discharge of untreated FGD blowdown.
The facility shall continue to operate the FGD treatment system until all coal-fired units are
retired.
Page 16 of 29

Permit NC0003425
A. (11)Effluent Limitations and Monitoring Requirements (Internal Outfall 012A) [15A NCAC 02B
.0400 et seq.,02B .0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration,the Permittee
is authorized to discharge from Internal Outfall 012A. Such discharges shall be limited and monitored)
by the Permittee as specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample
CHARACTERISTICS Average Maximum Frequency Sample Type Location
Flow Monthly Pump Logs or Effluent
similar reading
Total Suspended Solids 30.0 mg/L 100.0 mg/L Monthly Grab Effluent
Oil and grease 15.0 mg/L 20.0 mg/L Monthly Grab Effluent
Total Arsenic,µg/L Weekly3 Grab Effluent
Total Molybdenum,µg/L Weekly3 Grab Effluent
Total Selenium,µg/L Weekly3 Grab Effluent
Total Mercury,ng/L Weekly3 Grab Effluent
Total Antimony,µg/L Weekly3 Grab Effluent
Total Copper,µg/L Weekly3 Grab Effluent
pH Weekly3 Grab Effluent
Notes
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A. (29).
2. Samples taken in compliance with the monitoring requirements listed above shall be taken after
the treatment system and prior to mixing with other sources of wastewater.
3. Monitoring is only required when discharging east ash basin closure flows or treated groundwater
through this outfall.
Within 180 days of the commencement of operations of the treatment system the permittee shall submit
Items V and VI of NPDES application Form 2C.
Page 17 of 29

Permit NC0003425
A. (12)Effluent Limitations and Monitoring Requirements (Internal Outfall 012B) [15A NCAC 02B
.0400 et seq.,02B.0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration,the Permittee
is authorized to discharge from Internal Outfall 012B. Such discharges shall be limited and monitored)
by the Permittee as specified below:
LIMITS MONITORING REQUIREMENTS
EFFLUENT Q
Monthly Daily Measurement Sample
CHARACTERISTICS
Type
P
Sam l T e
Average Maximum Frequency Location2
Flow MonthlyPump Logs or Effluent
similar reading
Total Suspended Solids 30.0 mg/L 100.0 mg/L Monthly Grab Effluent
Oil and grease 15.0 mg/L 20.0 mg/L Monthly Grab Effluent
pH Quarterly Grab Effluent
Ammonia3 Daily3 Grab Effluent
Total Arsenic Monthly Grab Effluent
Total Selenium Monthly Grab Effluent
Total Mercury4 Monthly Grab Effluent
Notes
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A. (29).
2. Samples taken in compliance with the monitoring requirements listed above shall be taken after
the treatment system and prior to mixing with other sources of wastewater.
3. Ammonia limit and monitoring is only applicable in the event of an emergency release of
anhydrous ammonia during the time the released waters are discharged through outfall 012B.
4. The facility shall use EPA method 1631E.
Within 180 days of the commencement of operations of the treatment system the permittee shall submit
Items V and VI of NPDES application Form 2C.
Except for those discharges authorized below,or when the bottom ash transport water is used in
the FGD scrubber,there shall be no discharge of pollutants in bottom ash transport water.Bottom
ash transport water shall be discharged to the FGD scrubber during normal operations.
If the FGD Scrubber is unavailable to receive bottom ash transport water,the discharge of
pollutants in bottom ash transport water(bottom ash purge water)from a properly installed,
operated,and maintained bottom ash system to the Lined Retention Basin is authorized under the
following conditions:
A. To maintain system water balance when precipitation-related inflows are generated from a Y p P
10-
year storm event of 24-hour or longer duration(e.g.,30-day storm event)and cannot be
managed by installed spares,redundancies,maintenance tanks,and other secondary bottom
ash system equipment;or
B. To maintain system water balance when regular inflows from waste streams other than
bottom ash transport water exceed the ability of the bottom ash system to accept recycled
water and segregating these other waste streams is feasible;or
C. To maintain system water chemistry where current operations at the facility are unable to
currently manage pH,corrosive substances,substances or conditions causing scaling,or fine
particulates to below levels which impact system operation or maintenance;or
Page 18 of 29

Permit NC0003425
D. To conduct maintenance not otherwise described above and not exempted from the definition
of transport water in 40 C.F.R.§423.11(p),and when water volumes cannot be managed by
installed spares,redundancies,maintenance tanks,and other secondary bottom ash system
equipment.
In no event shall the total volume of the discharge to the Lined Retention Basin exceed a 30-day
rolling average of ten percent of the primary active wetted bottom ash system volume.The
volume of daily discharges used to calculate the 30-day rolling average shall be calculated using
measurements from flow monitors or pump logs. Based on a calculated bottom ash transport
system volume of 0.995 million gallons,the 30 day rolling average discharge shall not exceed 0.099
MGD.
Page 19 of 29

Permit NC0003425
A.(13)Effluent Limitations and Monitoring Requirements (Outfall 012C) [15A NCAC 02B .0400 et seq.,
02B.0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration,the Permittee
is authorized to discharge from Outfall 012C. Such discharges shall be limited and monitored"by the
Permittee as specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample
CHARACTERISTICS Average Maximum Frequency Sample Type Location
Flow Per discharge event Estimate Effluent
Total Suspended Solids 30.0 mg/L 100.0 mg/L Per discharge event Grab Effluent
Oil and grease 15.0 mg/L 20.0 mg/L Per discharge event Grab Effluent
pH 6.0 to 9.0 S.U. Per discharge event Grab Effluent
Ammonia3 1.0 mg/L 5.0 mg/L Per discharge event Grab Effluent
Total Arsenic,pg/L Per discharge event Grab Effluent
Total Mercury,ng/L Per discharge event Grab Effluent
Total Selenium,pg/L Per discharge event Grab Effluent
Nitrate/Nitrite as N, Per discharge event Grab Effluent
mg/L
Total Copper,pg/L Per discharge event Grab Effluent
Total Iron,pg/L Per discharge event Grab Effluent
Notes
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system.See Special Condition A. (29).
2. Samples taken in compliance with the monitoring requirements listed above shall be taken after
the treatment system and prior to mixing with other sources of wastewater.
3. Ammonia limit and monitoring is only applicable in the event of an emergency release of
anhydrous ammonia during the time the released waters are discharged at the same time as the
emergency overflow.
Within 180 days of the first discharge event the permittee shall submit Items V and VI of NPDES
application Form 2C.
All flows shall be reported on monthly DMRs. If no flow occurs during a given month,the words"no flow"
should be clearly written on the front of the DMR. All samples shall be of a representative discharge.
Page 20 of 29

Permit NC0003425
A. (14) Acute Toxicity Testing PASS/FAIL Permit Limit Outfalls 001 and 003 [15A NCAC 02B .0200 et
seq.]
The Permittee shall conduct acute toxicity tests on a quarterly basis using protocols defined in the North
Carolina Procedure Document entitled"Pass/Fail Methodology For Determining Acute Toxicity In A
Single Effluent Concentration" (Revised-December 2010 or subsequent versions).The monitoring shall be
performed as a Fathead Minnow(Pimephales promelas)24 hour static test.The effluent concentration at
which there may be at no time significant acute mortality is 90%(defined as treatment two in the
procedure document). The tests will be performed during the months of March,June,September and
December. These months signify the first month of each three month toxicity testing quarter assigned to
the facility. Effluent sampling for this testing must be obtained during representative effluent discharge
and shall be performed at the NPDES permitted final effluent discharge below all treatment processes.
The parameter code for Pimephales promelas is TGE6C. All toxicity testing results required as part of this
permit condition will be entered on the Effluent Discharge Form(MR-1)for the month in which it was
performed,using the appropriate parameter code.Additionally,DWR Form AT-2(original)is to be sent to
the following address:
Attention: North Carolina Division of Water Resources
Water Sciences Section/Aquatic Toxicology Branch
1621 Mail Service Center
Raleigh,North Carolina 27699-1621
Or,results can be sent to the email:[e-mail].
Completed Aquatic Toxicity Test Forms shall be filed with the Water Sciences Section no later than 30 days
after the end of the reporting period for which the report is made.
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests,as well as all dose/response data.Total residual chlorine
of the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of
the waste stream.
Should there be no discharge of flow from the facility during any month,the Permittee will complete the
information located at the top of the aquatic toxicity(AT)test form indicating the facility name,permit
number,pipe number,county,and the month/year of the report with the notation of"No Flow"in the
comment area of the form.The report shall be submitted to the Water Sciences Section at the address cited
above.
Should the Permittee fail to monitor during a month in which toxicity monitoring is required,then
monthly monitoring will begin immediately.Upon submission of a valid test,this monthly test
requirement will revert to quarterly in the months specified above
Should any test data from either these monitoring requirements or tests performed by the North Carolina
Division of Water Resources indicate potential impacts to the receiving stream,this permit may be re-
opened and modified to include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document,such as minimum control
organism survival and appropriate environmental controls,shall constitute an invalid test and will
require immediate follow-up testing to be completed no later than the last day of the month following the
month of the initial monitoring.
Page 21 of 29

Permit NC0003425
A. (15) Acute Toxicity Monitoring(ANNUAL)Outfall 006[15A NCAC 02B.0200 et seq.]
The permittee shall conduct annual acute toxicity tests using protocols defined as definitive in EPA
Document EPA-821-R-02-012 entitled"Methods for Measuring the Acute Toxicity of Effluents and
Receiving Waters to Freshwater and Marine Organisms."The monitoring shall be performed as a Fathead
Minnow(Pimephales promelas)24 hour static test.Effluent samples for self-monitoring purposes must be
obtained during representative effluent discharge and shall be performed at the NPDES permitted final
effluent discharge below all waste treatment processes.
The parameter code for Pimephales promelas is TAA6C. All toxicity testing results required as part of this
permit condition will be entered on the Effluent Discharge Form(MR-1)for the month in which it was
performed,using the appropriate parameter code.Additionally,DWR Form AT-1 (original)is to be sent to
the following address:
Attention: North Carolina Division of Water Resources
Water Sciences Section/Aquatic Toxicology Branch
1621 Mail Service Center
Raleigh,North Carolina 27699-1621
Or,results can be sent to the email:[e-mail].
Completed Aquatic Toxicity Test Forms shall be filed with the Water Sciences Section no later than 30 days
after the end of the reporting period for which the report is made.
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests,as well as all dose/response data.Total residual chlorine
of the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of
the waste stream.
Should there be no discharge of flow from the facility during any month,the permittee will complete the
information located at the top of the aquatic toxicity(AT)test form indicating the facility name,permit
number,pipe number,county,and the month/year of the report with the notation of"No Flow"in the
comment area of the form.The report shall be submitted to the Water Sciences Section at the address cited
above.
Should any test data from either these monitoring requirements or tests performed by the North Carolina
Division of Water Resources indicate potential impacts to the receiving stream,this permit may be re-
opened and modified to include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document,such as minimum control
organism survival and appropriate environmental controls,shall constitute an invalid test and will
require immediate follow-up testing to be completed no later than the last day of the month following the
month of the initial monitoring.
A. (16) Intake Screen Backwash Condition[NCGS 143-215.1(b)]
Continued intake screen backwash discharge is permitted without limitations or monitoring requirements.
A. (17) Temperature Requirements(Outfall 003 Mixing Zone) [NCGS 143-215.1(b)]
a. Water quality standards for temperature for lower piedmont waters(32°C)will not apply within a
mixing zone, which shall include the North Hyco arm downstream of NC Highway 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. The area described does not include the South Hyco Arm or the
first finger arms on the west side of the reservoir lying upstream of the dam.Water within the main
Page 22 of 29

Permit NC0003425
lake and the afterbay lake to Hyco River shall comply with water quality standards except the
temperature standards in the areas of the lake defined herein as a mixing zone. Water discharged
from the afterbay shall comply with the temperature standard. Temperature readings from the
afterbay shall be obtained from the existing USGS station(02077303).
b. Temperature measurements made to monitor compliance with this provision shall be made at least
six inches,but not more than one foot,below the surface of the lake.
c. Temperature shall be measured daily. In case where the permittee experiences equipment
problems and is unable to obtain daily temperatures from the monitoring station temperature
monitoring must be reestablished within five working days.
d. Temperature increases shall be determined as the increase in temperature above the background
level. Background level shall be defined as the temperature measured at the confluence of the two
southern finger arms on the north side of the lake (Lat. 36.5111, Long 79.06629).The downstream
compliance point shall be defined as the afterbay discharge.
e. A summary of the temperature monitoring results at all sampling locations as established in the
biological monitoring program for Hyco Reservoir and condition A.(4) shall be submitted to the
Division with the annual Biological MonitoringReport due byJuly31 of the followingyear.
gl P
A.(18) Instream Monitoring [NCGS 143-215.1(b)]
In accordance with the previously submitted biological monitoring program (as approved by the Director
of the Division, and as it may be amended), the Permittee shall submit results of biological studies and
monitoring programs by July 31 of the following year. The facility shall conduct monthly in-stream
monitoring at Station F2 (formerly 6B) for total arsenic, total selenium, total mercury, total chromium,
dissolved lead, dissolved cadmium, dissolved copper, dissolved zinc, total bromide, total hardness (as
CaCO3),turbidity,and total dissolved solids(TDS). The monitoring results shall be reported on the facility's
Discharge Monitoring Reports and included with the NPDES permit renewal application.
A. (19)Fish Tissue Monitoring Near Ash Pond Discharge[NCGS 143-215.3(a)(2)]
The facility shall conduct fish tissue monitoring annually and submit the results with the NPDES permit
renewal application. The objective of this monitoring is to evaluate potential uptake of pollutants by fish
tissue near the ash pond discharge. The parameters analyzed in fish tissue shall include arsenic,selenium,
and mercury. The monitoring shall be conducted in accordance with the sampling plan approved by the
Division.The plan should be submitted to the Division within 180 days from the effective date of the permit.
Upon approval,the plan becomes an enforceable part of the permit.
Copies of all the study plans,study results,and any other applicable materials should be submitted to:
Electronic Version Only(PDF and CD)
Division of Water Resources
WQ Permitting Section-NPDES
1617 Mail Service Center
Raleigh,NC 27699-1617
Electronic Version(PDF and CD)and Hard Copy
Division of Water Resources
Water Science Section
1621 Mail Service Center
Raleigh,NC 27699-1621
A.(20) Applicable State Law(State Enforceable Only) [NCGS 143-215.1(b)]
This facility shall meet the General Statute requirements under NCGS§130A-309.200 et seq.This permit
may be reopened to include new requirements imposed under these Statutes.
Page 23 of 29

Permit NC0003425
A. (21) Limitations Reopener[NCGS 143-215.1(b)]
The permit shall be modified,or revoked and reissued,to comply with any applicable effluent guideline
or water quality standard issued or approved under sections 302(b)(2)(c)and(d),304(b)(2)and 307(a)of
the Clean Water Act,if the effluent guideline or water quality standard so issued or approved:
a. Contains different conditions or is otherwise more stringent than any effluent limitation in the
permit;or
b. Controls a pollutant not limited in the permit.
The permit as modified or reissued under this paragraph shall also contain any other requirements in the
Act then applicable.
A. (22) Domestic Wastewater Treatment Plant[NCGS 143-215.1(b)]
The permittee shall at all times properly operate and maintain the domestic wastewater treatment plant to
meet secondary standards as specified for internal outfall 008.
A. (23) Bioreactor Condition[NCGS 143-215.1(b)]
An operation and maintenance plan, including a monitoring regimen for the bioreactor units and an
emergency response plan in the event of an upset, shall be maintained and available for inspection by
Division personnel.
A.(24) Ash Pond Closure[NCGS 143-215.1(b)]
The facility shall prepare an Ash Ponds Closure Plan.This Plan shall be submitted to the Division one month
prior to the closure of ash ponds.
A.(25) Clean Water Act Section 316(b) [40 CFR 125.95]
The permittee shall comply with the Cooling Water Intake Structure Rule per 40 CFR 125.95.The
permittee shall submit the following information as required in 122.21 (except 122.21 (r)(6))by May 31,
2023.
§122.21(r)(2)Source Water Physical Data
§/22.21(r)(3)Cooling Water Intake Structure Data
§122.21(r)(4)Source Water Baseline Biological Characterization Data
§/22.21(r)(5)Cooling Water System Data
§122.21(r)(6)Chosen Method(s)of Compliance with the Impingement Mortality Standard(the chosen
method will be defined after the site-specific BTA determination is made by the Director)
§122.21(r)(7)Entrainment Performance Studies
§122.21(r)(8)Operational Status
§122.21(r)(9)Entrainment Characterization Study
§122.21(r)(10)Comprehensive Technical Feasibility and Cost Evaluation Study
§122.21(r)(11)Benefits Valuation Study
§122.21(r)(12)Non-water Quality and Other Environmental Impacts Study
Based on the director's selection of entrainment,this permit may be reopened to establish a schedule to
implement the selected technology.
Copies of all the study plans,study results,and any other applicable materials should be submitted to:
Page 24 of 29

Permit NC0003425
1. Electronic Version Only(PDF and CD)
Division of Water Resources
WQ Permitting Section-NPDES
1617 Mail Service Center
Raleigh,NC 27699-1617
2. Electronic Version(PDF and CD)and Hard Copy
Division of Water Resources
Water Sciences Section
1623 Mail Service Center
Raleigh,NC 27699-1623
Based on 40 CFR 125.92(c)and 40 CFR 125.94(c)&(d),the Director has determined that operating and
maintaining the existing closed-cycle recirculating system meets the requirements for a provisional BTA.
The final determination will be made upon review of the materials submitted by the permittee.This
determination does not preclude the Division from implementing additional requirements to minimize
impingement and entrainment of the aquatic organisms based on the results of the studies.
The facility shall continue to demonstrate that make-up water withdrawals attributed specifically to the
cooling portion of the cooling system have been minimized.
Nothing in this permit authorizes take for the purposes of a facility's compliance with the Endangered
Species Act.
A.(26) Structural Integrity Inspections of Ash Pond Dam [15A NCAC 02K.0208]
The facility shall meet the dam design and dam safety requirements per 15A NCAC 2K.
A. (27) Biocide Condition[NCGS 143-215.1(b)]
The permittee shall not use any biocides except those approved in conjunction with the permit
application. The permittee shall notify the Director in writing not later than ninety (90) days prior to
instituting use of any additional biocide used in cooling systems which may be toxic to aquatic life other
than those previously reported to the Division of Water Resources. Such notification shall include
completion of Biocide Worksheet Form 101 and a map locating the discharge point and receiving stream.
Completion of Biocide Worksheet Form 101 is not necessary for those outfalls containing toxicity testing.
Division approval is not necessary for the introduction of new biocides into outfalls currently tested for
whole effluent toxicity.
A. (28)Compliance Boundary[15A NCAC 02L.0107]
The compliance boundary for the disposal system shall be specified in accordance with 15A NCAC 02L
.0107(a)or(b)dependent upon the date permitted. An exceedance of groundwater standards at or beyond
the compliance boundary is subject to remediation action according to 15A NCAC 02L.0106(c),(d),or(e)
as well as enforcement actions in accordance with North Carolina General Statute 143-215.6A through 143-
215.6C.
The compliance boundary maps for this facility are incorporated herein and attached hereto as
Attachments A and B.Attachment A includes the temporary compliance boundary around the East Ash
Basin Extension.Attachment B is the future compliance boundary effective upon completion of the
removal of coal ash from the East Ash Basin Extension.
Page 25 of 29

Permit NC0003425
A. (29)Electronic Reporting of Discharge Monitoring Reports P.S.143-215.1(b)]
Federal regulations require electronic submittal of all discharge monitoring reports(DMRs)and program
reports.The final NPDES Electronic Reporting Rule was adopted and became effective on December 21,
2015.
NOTE: This special condition supplements or supersedes the following sections within Part II of this
permit(Standard Conditions for NPDES Permits):
• Section B.(11.) Signatory Requirements
• Section D. (2.) Reporting
• Section D.(6.) Records Retention
• Section E. (5.) Monitoring Reports
1. Reporting Requirements[Supersedes Section D. (2.)and Section E. (5.) (all
The permittee shall report discharge monitoring data electronically using the NC DWR's Electronic
Discharge Monitoring Report(eDMR)internet application.
Monitoring results obtained during the previous month(s)shall be summarized for each month and
submitted electronically using eDMR. The eDMR system allows permitted facilities to enter
monitoring data and submit DMRs electronically using the internet. Until such time that the state's
eDMR application is compliant with EPA's Cross-Media Electronic Reporting Regulation
(CROMERR),permittees will be required to submit all discharge monitoring data to the state
electronicallyusingeDMR and will be required to complete the eDMR submission byprinting,
�l P P g
signing,and submitting one signed original and a copy of the computer printed eDMR to the
following address:
NC DENR/ Division of Water Resources/ Water Quality Permitting Section
ATTENTION: Central Files
1617 Mail Service Center
Raleigh,North Carolina 27699-1617
If a permittee is unable to use the eDMR system due to a demonstrated hardship or due to the facility
being physically located in an area where less than 10 percent of the households have broadband
access,then a temporary waiver from the NPDES electronic reporting requirements may be granted
and discharge monitoring data may be submitted on paper DMR forms(MR 1,1.1,2,3)or alternative
forms approved by the Director. Duplicate signed copies shall be submitted to the mailing address
above. See"How to Request a Waiver from Electronic Reporting" section below.
Regardless of the submission method,the first DMR is due on the last day of the month following the
issuance of the permit or in the case of a new facility,on the last day of the month following the
commencement of discharge.
Starting on December 21,2025,the permittee must electronically report the following compliance
monitoring data and reports,when applicable:
• Sewer Overflow/Bypass Event Reports;
• Pretreatment Program Annual Reports;and
• Clean Water Act(CWA)Section 316(b)Annual Reports.
The permittee may seek an electronic reporting waiver from the Division(see"How to Request a
Waiver from Electronic Reporting" section below).
Page 26 of 29

Permit NC0003425
2. Electronic Submissions
In accordance with 40 CFR 122.41(1)(9),the permittee must identify the initial recipient at the time of
each electronic submission. The permittee should use the EPA's website resources to identify the
initial recipient for the electronic submission.
Initial recipient of electronic NPDES information from NPDES-regulated facilities means the entity
(EPA or the state authorized by EPA to implement the NPDES program)that is the designated entity
for receiving electronic NPDES data [see 40 CFR 127.2(b)].
EPA plans to establish a website that will also link to the appropriate electronic reporting tool for each
type of electronic submission and for each state. Instructions on how to access and use the
appropriate electronic reporting tool will be available as well. Information on EPA's NPDES
Electronic Reporting Rule is found at: http://www2.epa.gov/compliance/final-national-pollutant-
discharge-elimination-system-npdes-electronic-reporting-rule.
Electronic submissions must start by the dates listed in the"Reporting Requirements" section above.
3. How to Request a Waiver from Electronic Reporting
The permittee may seek a temporary electronic reporting waiver from the Division. To obtain an
electronic reporting waiver,a permittee must first submit an electronic reporting waiver request to the
Division. Requests for temporary electronic reporting waivers must be submitted in writing to the
Division for written approval at least sixty(60)days prior to the date the facility would be required
under this permit to begin submitting monitoring data and reports. The duration of a temporary
waiver shall not exceed 5 years and shall thereupon expire. At such time,monitoring data and reports
shall be submitted electronically to the Division unless the permittee re-applies for and is granted a
new temporary electronic reporting waiver by the Division. Approved electronic reporting waivers
are not transferrable. Only permittees with an approved reporting waiver request may submit
monitoring data and reports on paper to the Division for the period that the approved reporting
waiver request is effective.
Information on eDMR and the application for a temporary electronic reporting waiver are found on
the following web page:
http://deq.nc.gov/about/divisions/water-resources/edmr
4. Signatory Requirements[Supplements Section B. (11.) (b)and Supersedes Section B.(11.)(d)j
All eDMRs submitted to the permit issuing authority shall be signed by a person described in Part II,
Section B. (11.)(a)or by a duly authorized representative of that person as described in Part II,Section
B. (11.)(b). A person,and not a position,must be delegated signatory authority for eDMR reporting
purposes.
For eDMR submissions,the person signing and submitting the DMR must obtain an eDMR user
account and login credentials to access the eDMR system. For more information on North Carolina's
eDMR system,registering for eDMR and obtaining an eDMR user account,please visit the following
web page:
http://deq.nc.gov/about/divisions/water-resources/edmr
Page 27 of 29

Permit NC0003425
Certification. Any person submitting an electronic DMR using the state's eDMR system shall make
the following certification[40 CFR 122.22]. NO OTHER STATEMENTS OF CERTIFICATION WILL
BE ACCEPTED:
"I certify, under penalty of law, that this document and all attachments were prepared under my direction or
supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate
the information submitted. Based on my inquiry of the person or persons who manage the system,or those
persons directly responsible for gathering the information, the information submitted is, to the best of my
knowledge and belief, true,accurate,and complete.I am aware that there are significant penalties for submitting
false information, including the possibility of fines and imprisonment for knowing violations."
5. Records Retention[Supplements Section D. (6.)1
The permittee shall retain records of all Discharge Monitoring Reports,including eDMR submissions.
These records or copies shall be maintained for a period of at least 3 years from the date of the report.
This period may be extended by request of the Director at any time[40 CFR 122.41].
A. (30)Additional Conditions And Definitions [NCGS 143-215.3(a)(2)and NCGS 143-215.66]
1. EPA methods 200.7 or 200.8(or the most current versions)shall be used for analyses of all metals
except for total mercury(EPA Method 1631E).
2. All effluent samples for all external outfalls shall be taken at the most accessible location after the
final treatment but prior to discharge to waters of the U.S. (40 CFR 122.41(j)).
3. The term low volume waste sources mean wastewater from all sources except those for which
specific limitations are otherwise established in this part(40 CFR 423.11 (b)).
4. The term chemical metal cleaning waste means any wastewater resulting from cleaning any metal
process equipment with chemical compounds,including,but not limited to,boiler tube cleaning
(40 CFI(423.11 (c)).
5. The term metal cleaning waste means any wastewater resulting from cleaning[with or without
chemical cleaning compounds]any metal process equipment including,but not limited to,boiler
tube cleaning,boiler fireside cleaning,and air preheater cleaning(40 CFR 423.11 (d)).
6. For all outfalls where the flow measurement is to be"estimated"the estimate can be done by
using calibrated V-notch weir,stop-watch and graduated cylinder,or other method approved by
the Division.
7. The term"FGD wet scrubber wastewater" means wastewater resulting from the use of the flue-gas
desulfurization wet scrubber.
8. There shall be no discharge of polychlorinated biphenyl compounds.
9. The permittee shall report the presence of cenospheres observed in any samples on the DMRs in
the comment section.
10. The applicant is permitted to discharge chemical metal cleaning wastes to the Lined Retention
Basin.
11. Nothing contained in this permit shall be construed as a waiver by the permittee of any right to a
hearing it may have pursuant to State or Federal laws and regulations.
Page 28 of 29

Permit NC0003425
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Duke Energy Progress-Roxboro Steam Station,Person County Facility Location
Receiving Stream: Hyco Reservoir Stream Class: WS-V,B *
Sub-Basin: 03-02-05 State Grid: B22NE/Olive Hill Al
Drainage Basin: Roanoke River Basin 'Y
Outfall 001:Latitude 36°29'1.25" Longitude 79°3'23.0"
Outfall 003:Latitude 36°28'48" Longitude 79°05'11"
Outfall 006:Latitude 36°19'13" Longitude 79°04'41" NPDES Permit NC0003425
Outfall 012C:Latitude:36°12914" Longitude 79°04'S5"
Page 29 of 29