NC0038377_Draft Permit_20180501

ROY COOPER
.:., Governo,
MICHAEL S.REGAN
Secretary
Water Resources a LINDA CULPEPPER
Environmental Quahty Interim Director
May 1, 2018
Mr. Harry Sideris, Senior Vice President
Environmental, Health and Safety
Duke Energy Carolinas, LLC
Mail Code EC 13K
P.O. Box 1006
Charlotte, North Carolina 28201-1006
Subject: Draft NPDES Permit
Permit NC0038377
Mayo Steam Electric Generating Plant
Person County
Facility Class I
Dear Mr. Sideris:
Enclosed with this letter is a copy of the draft permit for your facility. Please review the
draft very carefully to ensure thorough understanding of the conditions and requirements it
contains.
The draft permit contains the following significant changes from your current
permit:
• The effluent page for the ash pond with FGD wastewater was removed from the permit
since the facility eliminated the FGD discharge by installing the Vapor Compression
Evaporator (zero liquid discharge system).
• The daily maximum TSS limit was reduced to 50 mg/L from 100 mg/L (Outfall 002) to
meet the requirements of 40 CFR 423.
• The limits for Total Beryllium, Total Chlorides, and Total Fluoride (Outfall 002-
decanting) were added to the permit based on the results of Reasonable Potential
Analysis.
• The monitoring frequency for Total Copper and Total Arsenic were increased to Monthly
from Quarterly (Outfall 002 - decanting) based on the review of the effluent data.
• The monitoring for Total Iron (Outfall 002-decanting) was removed due to the
elimination the state standard for Iron during the last triennial review.
• The monitoring frequency for Total Selenium was reduced to Monthly from 2/Month
(Outfall 002-decanting) based on the results of the Reasonable Potential Analysis.
• The monitoring for Total Chromium, Turbidity, Total Zinc, Total Mercury, Total
Beryllium, Total Chlorides, Total Fluoride, Total Barium, Total Thallium, Total
Antimony, Total Boron, and Temperature (Outfall 002-decanting) were added to the
permit based on the review of the effluent data.
• The Selenium Study and Crutchfield Branch Special Conditions were eliminated from the
permit, they are replaced with Outfalls 101 and 102 for toe drains. Please see A. (8.) and
A. (9.).
• The monitoring frequency for the Whole Effluent Toxicity was increased to Monthly
(Outfall 002 - Dewatering) to=afl'dliratilsidg 'ff imminent.
State of North Carolina I Environmental Quality
1611 Mail Service Center I Raleigh,North Carolina 27699-1611
919-707-9000

• A separate effluent page for the dewatering of the ash pond (Outfall 002) was added to
the permit. Please see Condition A. (4.).
• The following monitoring parameters were eliminated (Outfall 009) to be consistent with
the latest update to 40 CFR 423: Total Beryllium, Total Cadmium, Total Chlorides, Total
Chromium, Total Copper, Total Fluoride, Total Lead, Total Manganese, Total Nickel,
Total Silver, Total Barium, Total Thallium, Total Vanadium, Total Antimony, Total
Boron, Total Cobalt, Total Molybdenum, Total Zinc, and TSS.
• The Technology Based Effluent Limits for Total Arsenic, Total Mercury, Total Selenium,
and Nitrate/nitrite as N were added to the permit (Outfall 009) based on the
requirements in 40 CFR 423.
• The monitoring frequency for Total Arsenic, Total Mercury, Total Selenium, and
Nitrate/nitrite as N was reduced to Quarterly (Outfall 009) based on the review of the
effluent data.
• The turbidity limit was added to the permit (Outfall 002) to meet the state turbidity
standard per 15A NCAC 2B .0211(3) (k).
• The Toe Drain Outfalls 101 and 102 (Please see A. (8.) and A. (9.)) were added to the
permit.
• The Domestic Wastewater Treatment Plant Special Condition was added to the permit to
assure compliance with the 40 CFR 133.102. Please see Special Condition A. (17.).
• The Additional Conditions and Defmitions Special Condition was added to the permit.
Please see Special Condition A. (18.).
• 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. The requirement to begin reporting
discharge monitoring data electronically using the NC DWR's Electronic Discharge
Monitoring Report (eDMR) Internet application has been added to your final NPDES
permit. [See Special Condition A. (19.)]
For information on eDMR, registering for eDMR and obtaining an eDMR user account,
please visit the following web page: http://dec.nc.gov/about/divisions/water-
resources/edmr.
For more information on EPA's final NPDES Electronic Reporting Rule, please visit the
following web site: https:j/www federalregister.gov/documents/2015/10/22/2015-
24954/national-pollutant-discharge-elimination-system-npdes-electronic-reporting-rule
• The Special Condition entitled Compliance Boundary was added to the permit. Please see
Special Condition A. (20).
• The special condition entitled "Structural Integrity Inspections of Ash Pond Dam" was
added to the permit in accordance with the new EPA requirements. Please see Special
Condition A. (21).
• The "Clean Water Act Section 316(b)" Special Condition was added to the permit. Please
see Special Condition A. (22.).
• The Fish Tissue Monitoring near Ash Pond Discharge Special Condition was added to the
permit. Please see Special Condition A. (23.).
• The Instream Monitoring Special Condition was added to the permit to monitor the impact
of the facility on the receiving stream. Please see Special Condition A. (24.).
• The Biocide Special Condition A. (25.) was added to the permit to be consistent with the
permitting procedure for power plants.
• The new internal outfall 002A was added to the permit to accommodate construction of
the new Retention Basin. Please see A. (5.).
• The new internal outfall 002B was added to the permit to accommodate construction of
the new yard sump. Please see A. (6.).

• The former Stormwater Outfalls 004, 005, 006c, 006d, and 006e were added to the
permit. Please see A. (10.) through A. (14.).
• The Internal Outfall 011 for domestic wastewater was added to the permit. Please see A.
(15.).
• The mixing zone for Chlorides was eliminated and the permit limits were reduced due to
the installation of the zero liquid discharge system for the FGD wastewater.
• The Applicable State Law special condition was added to the permit. Please see A. (26.).
Please provide any comments you have regarding the draft permit to this office by
June 1, 2018. 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 permit. Following the 30-day
comment period, we will review all pertinent comments received and take appropriate action on
the permit renewal.
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: 919-807-6386.
Sincerely,
k___..5"
Sergei Chernikov, Ph.D.
Environmental Engineer II
Complex NPDES Permitting Unit
cc: Central Files
NPDES Files
EPA Region IV
Raleigh Regional Office / Water Quality(e-copy)
Raleigh Regional Office / Public Water Supply Regional Engineer(e-copy)
WSS/Aquatic Toxicology Unit(e-copy)

Permit NC0038377
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 provision 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 and stormwater from a facihty located at the
Mayo Steam Electric Generating Plant
off of US Highway 501
northeast of Roxboro
Person County
to receiving waters designated as the Mayo Reservoir and Crutchfield Branch in the Roanoke River Basin in
accordance with effluent limitations,monitoring requirements, and other applicable conditions set forth in
Parts I, II, and III hereof.
The permit shall become effective
This permit and the authorization to discharge shall expire at midnight on.
Signed this day
DRAFT
Linda Culpepper, Interim Director
Division of Water Resources
By Authority of the Environmental Management
Commission
Page 1 of 26

Permit NC0038377
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 Mayo Steam Electric Generating Plant, off of US
Highway 501, northeast of Roxboro,Person County:
• Outfall 001. Cooling Tower System. Less than once per year the cooling towers and circulating
water system are drained by gravity and discharged directly to Mayo Reservoir.
• Outfall 002.Ash Pond Treatment System. Outfall 002 discharges directly to Mayo Reservoir.
The ash pond receives coal pile runoff, stormwater runoff, cooling tower blowdown, FGD
wastewater (overflow during sever storm events only), and various low volume wastes such as
boiler blowdown, oily waste treatment,wastes/backwash from the water treatment processes
including Reverse-Osmosis (RO) wastewater, plant area wash down water, equipment heat
exchanger water, groundwater,yard sump overflows, occasional piping leakage from limestone
slurry and FGD system, and treated domestic wastewater.
• Internal Outfall 008. Cooling tower blowdown is directly discharged to the ash pond. Cooling
tower blowdown is indirectly discharged to Mayo Reservoir via the ash pond treatment system
(Outfall 002).
• Internal Outfall 009. Discharge from the FGD blowdown treatment system. FGD blowdown is
indirectly discharged to Mayo Reservoir via the ash pond treatment system (Outfall 002)
• Outfall 002A. Upon completion of construction, discharge from the new lined retention basin.
Basin will accept wastes from holding cell (vacuumed sediments and solids), coal pile runoff,
stormwater runoff, cooling tower blowdown, and various low volume wastes such as boiler
blowdown, oily waste treatment,wastes/backwash from the water treatment processes including
Reverse-Osmosis (RO) wastewater, plant area wash down water, equipment heat exchanger water,
groundwater, occasional piping leakage from limestone slurry and FGD system, chemical metal
cleaning waste, and treated domestic wastewater. The wastewater from this outfall discharges to
Mayo reservoir via the Outfall 002 location.
• Internal Outfall 002B.Yard sump overflows (contain all wastes routed to the new retention
basin).The wastewater from this outfall discharges to Mayo reservoir via the Outfall 002.
• Toe Drain Outfalls 101 (lat.: 36.53890;long. -78 89351) and 102 (lat.: 36.53890;long.: -78.89341)
-2 potentially contaminated toe drains.These toe drains discharge to effluent channels that flow to
Crutchfield Branch.
Page 2 of 26

Permit NC0038377
• Internal outfall 011 Domestic wastewater plant.The wastewater from this outfall discharges to
Mayo Reservoir via Outfall 002
• Outfalls 004, 005, 006c, 006d, and 006e. These are former stormwater outfalls, they primarily
contain stormwater and groundwater with some additional dust suppression irrigation,and cooling
tower drift. These outfalls discharge to Mayo Reservoir
2. Discharge from said treatment works and/or outfalls at the locations specified on the attached map into
Mayo Reservoir,which is classified as WS-V waters, and Crutchfield Branch,which is classified as C
waters in the Roanoke River Basin.
Page 3 of 26

Permit NC0038377
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 the permit and lasting until expiration, the Permittee is
authorized to discharge from Outfall 001 (Cooling Tower System). Monitoring is required only during
discharge events to the Mayo reservoir. Such discharges shall be limited and monitored4 by the Permittee as
specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Type Sample
Average Maximum Frequency Locationl
Flow Daily Pump Logs or Effluent
similar readings
Free Available 200 µg/L 500 µg/L Weekly Grab Effluent
Chloriie2
Time of Chlorine 2 hours Weekly Logs
Addition2
Total Chromium3 0.2 mg/L 0.2 mg/L 2 / Month Grab Effluent
Total Zinc3 1.0 mg/L 1.0 mg/L 2 / Month Grab Effluent
Priority Pollutants 3 No Detectable Amount Annual Grab Effluent
Temperature, °C Daily Grab Effluent
pH > 6.0 and < 9.0 standard units Weekly Grab Effluent
Notes.
1. Samples taken in compliance with the monitoring requirements listed above shall consist of cooling tower
effluent prior to its discharge to Mayo Reservoir.
2. Monitoring is required only if chlorine-based compounds are added to the system. Neither free available
chlorine nor total residual chlorine may be discharged from any single generating unit for more than two
hours per day,unless the Permittee demonstrates to the Division of Water Resources that discharge for
more than two hours is required for macroinvertebrate control. The 500 µg/L limitation is an
instantaneous maximum and is to be measured during the chlorine release period. The 200 µg/L
limitation is an average during the chlorine release period. Simultaneous multi-unit chlorination is
permitted.
3. 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.
4. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
The above listed effluent limitations shall be sampled prior to draining the cooling tower(s), at a location
prior to discharge to Mayo Reservoir.There shall be no discharge of polychlorinated biphenyl compounds
such as those commonly used for transformer fluid.
Page 4 of 26

Permit NC0038377
A. (2.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Internal Outfall 008)
[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 008 (Internal outfall, Cooling Tower System). Such discharges shall be
limited and monitored4 by the Peinuttee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Locationl
Flow Daily Pump Logs Effluent
or similar
readings
Free Available 200 µg/L 500 µg/L Weekly Grab Effluent
Chlorine2
Time of Chlorine 2 hours Weekly Logs
Addition2
Total Chromium3 0.2 mg/L 0.2 mg/L 2 / Month Grab Effluent
Total Zinc3 1.0 mg/L 1 0 mg/L 2 / Month Grab Effluent
Priority Pollutants 3 No Detectable Amount Annual Grab Effluent
pH > 6.0 and < 9.0 standard Weekly Grab Effluent
units
Notes.
1. Samples taken in compliance with the monitoring requirements listed above shall consist of cooling
tower blowdown.
2 Monitoring is required only if chlorine-based compounds are added to the system. Neither free
available chlorine nor total residual chlorine may be discharged from any single generating unit for
more than two hours per day,unless the Permittee demonstrates to the Division of Water Resources
that discharge for more than two hours is required for macroinvertebrate control. The 500 µg/L
limitation is an instantaneous maximum and is to be measured during the chlorine release period
The 200 pg/L limitation is an average during the chlorine release period. Simultaneous multi-unit
chlorination is permitted
3. 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
4. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19).
This outfall is not authorized to discharge directly to the Mayo Reservoir.
Page 5 of 26

Permit NC0038377
A (3.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Outfall 002-normal
operation/decanting)
[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 002(decanting the free water above the settled ash layer that does
not involve mechanical disturbance of the ash). These requirements shall remain in effect during
the term of the permit. Such discharges shall be limited and monitored'by the Permittee as specified below.
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location
Pump Logs
Flow Weekly or similar Effluent
readings
Oil and Grease 15.0 mg/L 20.0 mg/L Monthly Grab Effluent
Total Suspended Solids' 30.0 mg/L 50.0 mg/L Monthly Grab Effluent
Turbidity', NTU Monthly Grab Effluent
Total Selenium Monthly Grab Effluent
Total Chromium,pg/L Monthly Grab Effluent
Total Copper, µg/L Monthly Grab Effluent
Total Zinc, µg/L Monthly Grab Effluent
Acute Toxicity' Quarterly Grab Effluent
Total Mercury' Monthly Grab Effluent
Total Arsenic Monthly Grab Effluent
Total Beryllium 6.5 µg/L 65.0 µg/L Weekly Grab Effluent
Total Chlorides 250.0 mg/L 250.0 mg/L Weekly Grab Effluent
Total Fluoride 1,800.0 pg/L 1,800.0 µg/L Weekly Grab Effluent
Total Barium,mg/L Monthly Grab Effluent
Total Thallium Weekly Grab Effluent
Total Antimony, µg/L Monthly Grab Effluent
Total Boron, mg/L Monthly Grab Effluent
Temperature, °C Daily Grab Effluent
pH6 > 6.0 and < 9 0 standard units 2 /Month Grab Effluent
Notes:
Samples taken in compliance with the monitoring requirements listed above shall be taken prior to mixing
with other waste streams
1. Acute Toxicity (Fathead Minnow 24-hr) No significant mortality at 90% Please See Special
Condition A. (16.).
2 The facility shall use EPA method 1631E.
3. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system Please See Special Condition A (19.).
4. The discharge from this facility shall not cause turbidity in the receiving stream to exceed 50 NTU If
the instream turbidity exceeds 50 NTU due to natural background conditions, the discharge cannot
cause turbidity to increase in the receiving stream. Therefore,if the effluent measurement exceeds 50
NTU, the Permittee shall sample upstream and downstream turbidity in the receiving waterbody,
within 24 hours, to demonstrate the existing turbidity level in the receiving waterbody was not
increased.All data shall be reported on the DMRs. (See 15A NCAC 2B .0211 (21)).
Page 6 of 26

Permit NC0038377
NTU -Nephelometric Turbidity Unit.
5. The facility shall continuously monitor TSS concentration when the decanting process commences
and the 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 is only required when the pumps are employed.
6. 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. The continuous pH monitoring is only required when the pumps
are employed.
There shall be no discharge of floating solids or visible foam in other than trace amounts outside an area five
(5) meters from the discharge pipe. There shall be no discharge of polychlorinated biphenyl compounds
such as those commonly used for transformer fluid.
The facility is allowed to drawdown the wastewater in the ash pond to no less than three feet above
the ash. 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.
The facility shall use a floating pump station with free water skimmed from the basin surface using
an adjustable weir.
The limits and conditions in Section A. (4.) of the permit apply when water in the ash settling basin
is lowered below the three feet trigger mark.
By November 1,2018 there shall be no discharge of pollutants in fly ash transport water. This
requirement only applies to fly ash transport water generated after November 1,2018. By November
1,2018 there shall be no discharge of pollutants in bottom ash transport water. This requirement
only applies to bottom ash transport water generated after November 1,2018.
The facility shall notify DWR Complex NPDES Permitting Unit and DWR Raleigh Regional
Office,in writing, seven calendar days prior to the commencement of the decanting.
When the facility commences the ash pond/ponds decanting, the facility shall treat the wastewater
discharged from the ash pond/ponds 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 7 of 26

Permit NC0038377
A. (4.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS- (Outfall 002-
dewatermg)
[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 002 (dewatering-removing the interstitial water). Such discharges
shall be limited and monitored3 by the Permittee as specified below:
PARAMETER LIMITS _ MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location
Pump Logs
Flow 2.0 MGD8 Weekly or similar Effluent
readings
Oil and Grease 15.0 mg/L 20.0 mg/L Weekly Grab Effluent
Total Suspended Sohds5 30.0 mg/L 50.0 mg/L Weekly Grab Effluent
Turbidity',NTU Weekly Grab Effluent
Total Selenium Weekly Grab Effluent
Acute Toxicity' Monthly Grab Effluent
Total Mercury',ng/L Weekly Grab Effluent
Total Arsenic 10.0 µg/L 340.0 pg/L Weekly Grab Effluent
Total Cadmium 0.59 pg/L 3.24µg/L Weekly Grab Effluent
Total Chlorides 250.0 mg/L 250.0 mg/L Weekly Grab Effluent
Chromium (111)6 117.7 µg/L 905.1 µg/L Weekly Grab Effluent
Chromium (VI) 11.0 µg/L 16.0 µg/L Weekly Grab Effluent
Total Chromium, µg/L Weekly Grab Effluent
Total Copper 7.88 µg/L 10.47 µg/L Weekly Grab Effluent
Total Fluoride,µg/L Weekly Grab Effluent
Total Lead 2.94µg/L 75 51,ig/L Weekly Grab Effluent
Total Nickel 25.0 µg/L 335.2µg/L Weekly Grab Effluent
Total Zinc 126.7 µg/L 125.7 µg/L Weekly Grab Effluent
Total Barium 1.0 mg/L 1.0 mg/L Weekly Grab Effluent
Total Thallium 2.0 µg/L 2 0 µg/L Weekly Grab Effluent
Total Antimony, µg/L Weekly Grab Effluent
Total Boron,mg/L Weekly Grab Effluent
Temperature, °C Daily Grab Effluent
pH7 > 6.0 and < 9.0 standard units Weekly Grab Effluent
Notes:
Samples taken in compliance with the monitoring requirements listed above shall be taken prior to mixing
with other waste streams.
1. Acute Toxicity (Fathead Minnow 24-hr) No significant mortality at 90%;Please see Special Condition
A. (16).
2. The facility shall use EPA method 1631E.
3. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
4. The discharge from this facility shall not cause turbidity in the receiving stream to exceed 50 NTU. If
the instream turbidity exceeds 50 NTU due to natural background conditions, the discharge cannot
cause turbidity to increase in the receiving stream. Therefore,if the effluent measurement exceeds 50
Page 8 of 26

Permit NC0038377
NTU, the Permittee shall sample upstream and downstream turbidity in the receiving waterbody,
within 24 hours,to demonstrate the existing turbidity level m the receiving waterbody was not
increased.All data shall be reported on the DMRs. (See 15A NCAC 2B .0211 (21)).
NTU -Nephelometric Turbidity Unit.
5. The facility shall continuously monitor TSS concentration when the dewatering process commences
and the 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.
6. Cr(III)=Total Chromium-Chromium(V1).
7. The facility shall continuously monitor pH when the dewatering process commences and the
dewatering 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.The continuous pH monitoring only required when the
pumps are employed.
8. The flow limit applies only to the water removed from the interstitial pore space.
There shall be no discharge of floating solids or visible foam in other than trace amounts outside an area five
(5) meters from the discharge pipe. There shall be no discharge of polychlorinated biphenyl compounds
such as those commonly used for transformer fluid.
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.
By November 1,2018 there shall be no discharge of pollutants in fly ash transport water.This
requirement only applies to fly ash transport water generated after November 1,2018.
By November 1,2018 there shall be no discharge of pollutants in bottom ash transport water. This
requirement only applies to bottom ash transport water generated after November 1,2018.
The facility shall notify DWR Complex NPDES Permitting Unit and DWR Raleigh Regional
Office,in writing, seven calendar days prior to the commencement of the dewatering.
When the facility commences the ash pond/ponds dewatering, the facility shall treat the wastewater
discharged from the ash pond/ponds 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 9 of 26

Permit NC0038377
A. (5.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Outfall 002A)
[15A NCAC 02B .0400 et seq, 02B 0500 et seq.]
During the period beginning upon the commencement of operations of the new Retention Basin and lasting
until expiration,the Permittee is authorized to discharge from Internal Outfall 002A (new retention basin).
Such discharges shall be limited and monitored2 by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location
Flow,MGD Weekly Instantaneous Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Quarterly Grab Effluent
Total Suspended Solids 30.0 mg/L 50.0 mg/L Quarterly Grab Effluent
Temperature,°C Daily Grab Effluent
Total Arsenic Quarterly Grab Effluent
Total Mercury' Quarterly Grab Effluent
Total Selenium Quarterly Grab Effluent
Nitrate/nitrite as N Quarterly Grab Effluent
Chloride,mg/L Quarterly Grab Effluent
Total Nickel,µg/L Quarterly Grab Effluent
Sulfate,mg/L Quarterly Grab Effluent
Fluoride, µg/L Quarterly Grab Effluent
Total Barium,mg/L Quarterly Grab Effluent
Total Chromium, µg/L Quarterly Grab Effluent
Notes:
1. The facility shall use EPA method 1631E.
2. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
There shall be no discharge of floating solids or visible foam in other than trace amounts outside an area five
(5) meters from the discharge pipe There shall be no discharge of polychlorinated biphenyl compounds
such as those commonly used for transformer fluid.
Page 10 of 26

Permit NC0038377
A. (6.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Internal Outfall 002B)
[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 002B (yard sump overflow). Such discharges shall be limited
and monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location
Flow, MGD Per discharge Pump logs or
event estimate Effluent
Oil and Grease 15.0 mg/L 20 0 mg/L Per discharge Grab Effluent
event
Total Suspended Solids 30.0 mg/L 50.0 mg/L Per discharge Grab Effluent
event
pH, standard units Per discharge Grab Effluent
event
Notes:
1 The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A (19.).
A. (7) 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 (treated FGD wet scrubber wastewater). Such discharges
shall be limited and monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location
Flow,MGD Weekly Instantaneous Effluent
Total Arsenic 8.0µg/L2 11.0 µg/L2 Quarterly Grab Effluent
Total Mercury' 356.0 ng/L2 788.0 ng/L2 Quarterly Grab Effluent
Total Selenium 12.0 µg/L2 23.0 p.g/L2 Quarterly Grab Effluent
Nitrate/nitrite as N 4.4 mg/L2 17.0 mg/L2 Quarterly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Quarterly Grab Effluent
Total Suspended Quarterly Grab Effluent
Solids 30.0 mg/L 50 0 mg/L
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
2. The TBEL limits shall become effective on November 1, 2018
3. The facility shall use EPA method 1631E.
Page 11 of 26

Permit NC0038377
A. (8.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Outfall 101)
[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 101 —Toe Dram Discharge. Such discharges shall be limited and
monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency Type Location
Flow,MGD Monthly/Quarterly Estimate Effluent
pH3 Monthly/Quarterly Grab Effluent
TSS 30.0 mg/L 100.0 mg/L Monthly/Quarterly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Monthly/Quarterly Grab Effluent
Fluoride,µg/L Monthly/Quarterly Grab Effluent
Total Mercury',ng/L Monthly/Quarterly Grab Effluent
Total Barium,mg/L Monthly/Quarterly Grab Effluent
Total Zinc, µg/L Monthly/Quarterly Grab Effluent
Total Arsenic Monthly/Quarterly Grab Effluent
Total Boron,µg/L Monthly/Quarterly Grab Effluent
Total Cadmium, µg/L Monthly/Quarterly Grab Effluent
Total Chromium, µg/L Monthly/Quarterly Grab Effluent
Total Copper, µg/L Monthly/Quarterly Grab Effluent
Total Lead, µg/L Monthly/Quarterly Grab Effluent
Total Nickel, µg/L Monthly/Quarterly Grab Effluent
Total Selenium, µg/L Monthly/Quarterly Grab Effluent
Nitrate/nitrite as N, Monthly/Quarterly Grab Effluent
mg/L
Sulfates,mg/L Monthly/Quarterly Grab Effluent
Chlorides,mg/L Monthly/Quarterly Grab Effluent
1'DS,mg/L Monthly/Quarterly Grab Effluent
Total Hardness,mg/L Monthly/Quarterly Grab Effluent
Temperature, °C Monthly/Quarterly Grab Effluent
Conductivity, µmho/cm Monthly/Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A (19.)
2. The facility shall conduct monthly sampling from the effective date of the permit.After one year from
the effective date of the permit the monitoring will be reduced to quarterly
3. The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units.
4 The facility shall use EPA method 1631E.
If no discharge occurs during the reporting period or the Permittee is unable to obtain a
representative sample due to low-flow conditions at the toe drain, the Permittee shall submit its
DMR, as required, and indicate "No Flow" for the toe drain (15A NCAC 02B .0506(a)(1)(E)).
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 12 of 26

Permit NC0038377
A. (9.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Outfall 102)
[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 102—Toe Drain Discharge. Such discharges shall be limited and
monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency' Type Location
Flow,MGD Monthly/Quarterly Estimate Effluent
pH' Monthly/Quarterly Grab Effluent
TSS 30.0 mg/L 100.0 mg/L Monthly/Quarterly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Monthly/Quarterly Grab Effluent
Fluoride, µg/L Monthly/Quarterly Grab Effluent
Total Mercury',ng/L Monthly/Quarterly Grab Effluent
Total Barium, mg/L Monthly/Quarterly Grab Effluent
Total Zinc, µg/L Monthly/Quarterly Grab Effluent
Total Arsenic Monthly/Quarterly Grab Effluent
Total Boron, µg/L Monthly/Quarterly Grab Effluent
Total Cadmium, µg/L Monthly/Quarterly Grab Effluent
Total Chromium, µg/L Monthly/Quarterly Grab Effluent
Total Copper, µg/L Monthly/Quarterly Grab Effluent
Total Lead, µg/L Monthly/Quarterly Grab Effluent
Total Nickel, µg/L Monthly/Quarterly Grab Effluent
Total Selenium Monthly/Quarterly Grab Effluent
Nitrate/nitrite as N, Monthly/Quarterly Grab Effluent
mg/L
Sulfates,mg/L Monthly/Quarterly Grab Effluent
Chlorides,mg/L Monthly/Quarterly Grab Effluent
1'DS, mg/L Monthly/Quarterly Grab Effluent
Total Hardness,mg/L Monthly/Quarterly Grab Effluent
Temperature, °C Monthly/Quarterly Grab Effluent
Conductivity, µmho/cm Monthly/Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
2. The facility shall conduct monthly sampling from the effective date of the permit. After one year from
the effective date of the permit the monitoring will be reduced to quarterly
3. The pH shall not be less than 6 0 standard units nor greater than 9.0 standard units.
4. The facility shall use EPA method 1631E.
If no discharge occurs during the reporting period or the Permittee is unable to obtain a
representative sample due to low-flow conditions at the toe drain, the Permittee shall submit its
DMR, as required, and indicate "No Flow" for the toe drain (15A NCAC 02B .0506(a)(1)(E)).
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 13 of 26

Permit NC0038377
The facility shall install a screen or a barrier downstream of the confluence of the discharge from Outfall 001 and
Outfall 002 to minimize fish migration into the effluent channels that are combining at S-3 The design of the
screen/barrier shall be subnutted to the Division for approval no later than 6 months from the effective date of the
permit.The screen/barrier shall be installed no later than 6 months after Division approval
Page 14 of 26

Permit NC0038377
A. (10.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Outfall 004)
[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 004—Former stormwater outfall. Such discharges shall be limited and
monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency' Type Location
Flow,MGD Monthly/Quarterly Estimate Effluent
pH' Monthly/Quarterly Grab Effluent
TSS 30.0 mg/L 100.0 mg/L Monthly/Quarterly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Monthly/Quarterly Grab Effluent
Total Mercury',ng/L Monthly/Quarterly Grab Effluent
Total Zinc,µg/L Monthly/Quarterly Grab Effluent
Total Arsenic, pg/L Monthly/Quarterly Grab Effluent
Total Chromium,µg/L Monthly/Quarterly Grab Effluent
Total Copper, µg/L Monthly/Quarterly Grab Effluent
Total Selenium,µg/L Monthly/Quarterly Grab Effluent
Total Hardness,mg/L Monthly/Quarterly Grab Effluent
Temperature,°C Monthly/Quarterly Grab Effluent
Conductivity,µmho/cm Monthly/Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
2. The facility shall conduct monthly sampling from the effective date of the permit.After one year from
the effective date of the permit the monitoring will be reduced to quarterly
3. The pH shall not be less than 6.0 standard units nor greater than 9 0 standard units.
4. The facility shall use EPA method 1631E.
5. The facility shall submit EPA Form 2C for this Outfall as soon as practicable,but no later than 180 days
from the effective date of this penult.
There shall be no discharge of floating solids or visible foam m other than trace amounts.
Page 15 of 26

Permit NC0038377
A. (11.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Outfall 005)
[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 005—Former stormwater outfall. Such discharges shall be limited and
monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement rSample Sample
Average Maximum Frequency' Type Location
Flow,MGD Monthly/Quarterly Estimate Effluent
pH3 Monthly/Quarterly Grab Effluent
TSS 30.0 mg/L 100.0 mg/L Monthly/Quarterly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Monthly/Quarterly Grab Effluent
Total Mercury',ng/L Monthly/Quarterly Grab Effluent
Total Zoic,µg/L Monthly/Quarterly Grab Effluent
Total Arsenic,pg/L Monthly/Quarterly Grab Effluent
Total Chromium, µg/L Monthly/Quarterly Grab Effluent
Total Copper, µg/L Monthly/Quarterly Grab Effluent
Total Selenium, µg/L Monthly/Quarterly Grab Effluent
Total Hardness,mg/L Monthly/Quarterly Grab Effluent
Temperature,°C Monthly/Quarterly Grab Effluent
Conductivity,µmho/cm Monthly/Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
2. The facility shall conduct monthly samphng from the effective date of the permit.After one year from
the effective date of the permit the monitoring will be reduced to quarterly.
3. The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units.
4. The facility shall use EPA method 1631E.
5. The facility shall submit EPA Form 2C for this Outfall as soon as practicable,but no later than 180 days
from the effective date of this permit.
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 16 of 26

Permit NC0038377
A. (12.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Outfall 006c)
[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 006c—Former stormwater outfall. Such discharges shall be hunted and
monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequencyz Type Location
Flow,MGD Monthly/Quarterly Estimate Effluent
pH' Monthly/Quarterly Grab Effluent
TSS 30.0 mg/L 100.0 mg/L Monthly/Quarterly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Monthly/Quarterly Grab Effluent
Total Mercury',ng/L Monthly/Quarterly Grab Effluent
Total Zinc,µg/L Monthly/Quarterly Grab Effluent
Total Arsenic,µg/L Monthly/Quarterly Grab Effluent
Total Chromium, µg/L Monthly/Quarterly Grab Effluent
Total Copper, µg/L Monthly/Quarterly Grab Effluent
Total Selenium, µg/L Monthly/Quarterly Grab Effluent
Total Hardness,mg/L Monthly/Quarterly Grab Effluent
Temperature,°C Monthly/Quarterly Grab Effluent
Conductivity, µ.mho/cm Monthly/Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
2. The facility shall conduct monthly sampling from the effective date of the permit.After one year from
the effective date of the permit the monitoring will be reduced to quarterly
3. The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units.
4. The facility shall use EPA method 1631E.
5. The facility shall submit EPA Form 2C for this Outfall as soon as practicable,but no later than 180 days
from the effective date of this permit.
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 17 of 26

Permit NC0038377
A. (13.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Outfall 006d)
[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 006d—Former stormwater outfall. Such discharges shall be limited and
monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency' Type Location
Flow,MGD Monthly/Quarterly Estimate Effluent
pH' Monthly/Quarterly Grab Effluent
TSS 30.0 mg/L 100.0 mg/L Monthly/Quarterly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Monthly/Quarterly Grab Effluent
Total Mercury',ng/L Monthly/Quarterly Grab Effluent
Total Zinc, µg/L Monthly/Quarterly Grab Effluent
Total Arsenic, µg/L Monthly/Quarterly Grab Effluent
Total Chromium, µg/L Monthly/Quarterly Grab Effluent
Total Copper, µg/L Monthly/Quarterly Grab Effluent
Total Selenium, µg/L Monthly/Quarterly Grab Effluent
Total Hardness,mg/L Monthly/Quarterly Grab Effluent
Temperature, °C Monthly/Quarterly Grab Effluent
Conductivity, µmho/cm Monthly/Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
2. The facility shall conduct monthly sampling from the effective date of the permit.After one year from
the effective date of the permit the monitoring will be reduced to quarterly
3. The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units
4. The facility shall use EPA method 1631E.
5. The facility shall submit EPA Form 2C for this Outfall as soon as practicable,but no later than 180 days
from the effective date of this permit.
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 18 of 26

Permit NC0038377
A. (14.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Outfall 006e)
[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 006e—Former stormwater outfall. Such discharges shall be limited and
monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measurement Sample Sample
Average Maximum Frequency2 Type Location
Flow,MGD Monthly/Quarterly Estimate Effluent
pH' Monthly/Quarterly Grab Effluent
TSS 30.0 mg/L 100.0 mg/L Monthly/Quarterly Grab Effluent
Oil and Grease 15.0 mg/L 20.0 mg/L Monthly/Quarterly Grab Effluent
Total Mercury',ng/L Monthly/Quarterly Grab Effluent
Total Zinc, µg/L Monthly/Quarterly Grab Effluent
Total Arsenic, µg/L Monthly/Quarterly Grab Effluent
Total Chromium,µg/L Monthly/Quarterly Grab Effluent
Total Copper, µg/L Monthly/Quarterly Grab Effluent
Total Selenium, µg/L Monthly/Quarterly Grab Effluent
Total Hardness,mg/L Monthly/Quarterly Grab Effluent
Temperature,°C Monthly/Quarterly Grab Effluent
Conductivity,µmho/cm Monthly/Quarterly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system. Please See Special Condition A. (19.).
2. The facihty shall conduct monthly sampling from the effective date of the permit.After one year from
the effective date of the permit the monitoring will be reduced to quarterly.
3. The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units.
4. The facility shall use EPA method 1631E.
5. The facility shall submit EPA Form 2C for this Outfall as soon as practicable,but no later than 180 days
from the effective date of this permit.
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 19 of 26

Permit NC0038377
A (15.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (Internal Outfall 011)
[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 011 (domestic wastewater plant). Such discharges shall be
limited and monitored' by the Permittee as specified below:
PARAMETER LIMITS MONITORING REQUIREMENTS
Monthly Daily Measureme Sample Sample
Average Maximum nt Type Location
Frequency ,
Flow,MGD Weekly Instantaneous Effluent
BOD, 5-day,20°C 30.0 mg/L 45.0 mg/L Weekly Grab Effluent
TSS 30.0 mg/L 45.0 mg/L Weekly Grab Effluent
Fecal Coliform (geo. mean) 200/100 mL 400/100 mL Weekly Grab Effluent
Notes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR
application system Please See Special Condition A. (19.).
Page 20 of 26

Permit NC0038377
A. (16.) ACUTE TOXICITY PASS/FAIL PERMIT LIMIT (Monthly/Quarterly) (Outfall 002)
[15A NCAC 02B .0400 et seq., 02B .0500 et seq.]
The permittee shall conduct acute toxicity tests on a monthly 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 July, 1992 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). Effluent
samples for self-monitoring purposes must be obtained during representative effluent discharge below all waste
treatment.
All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge
Monitoring Form (MR-1) for the month in which it was performed, using the parameter code TGE6C
Additionally,DWR Form AT-2 (original) is to be sent to the following address.
Attention: North Carolina Division of Water Resources
Water Sciences Section
1621 Mail Service Center
Raleigh, North Carolina 27699-1621
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 a month in which toxicity monitoring is required,
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. (17.) DOMESTIC WASTEWATER TREATMENT PLANT
[40 CFR 133]
The domestic wastewater treatment plant shall be properly operated and maintained to ensure treatment of
domestic wastewater to secondary levels.
Page 21 of 26

Permit NC0038377
A. (18.) 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(i)).
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 hmited to,boiler tube cleaning (40 CFR
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.
10. The applicant is permitted to discharge chemical metal cleaning wastes to the ash 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.
A. (19.) ELECTRONIC REPORTING OF DISCHARGE MONITORING REPORTS
[G 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.) (a)]
The permittee shall report discharge monitoring data electronically using the NC DWR's Electronic
Discharge Monitoring Report (eDMR) Internet application.
Page 22 of 26

Permit NC0038377
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 electronically using eDMR
and will be required to complete the eDMR submission by printing, 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 21,2020, 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).
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 estabhsh 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-ellnination-
system-npdes-electronic-reporting-rule.
Page 23 of 26

Permit NC0038377
Electronic submissions must start by the dates hsted 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)]
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
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 cert, 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 sign f cant penalties for submitting false information, including the posszbili y of fines and imprisonment for
knowing violations."
Page 24 of 26

Permit NC0038377
5. Records Retention [Supplements Section D. (6)]
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. (20.) 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 as Attachments
A and B.
A. (21.) 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. (22) 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 all the materials required by the Rule with the next renewal application.
Copies of all the study plans, study results,and any other applicable materials should be submitted to
1) Electronic Version Only (pdf and CD)
Division of Water Resources •
WQ Permitting Secnon-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
A. (23.)FISH TISSUE MONITORING NEAR ASH POND DISCHARGE—OUTFALL 002
[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.
Page 25 of 26

Permit NC0038377
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:
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
1621 Mail Service Center
Raleigh,NC 27699-1621
A. (24.) INSTREAM MONITORING
[15A NCAC 02B.0500 ET SEQ.]
The facility shall conduct monthly in-stream monitoring (-550 ft. from Outfall 002 at sampling station B1) for
total arsenic, total selenium, total mercury, total chromium, dissolved lead, dissolved cadmium, dissolved
copper, dissolved zinc, total bromide, total hardness (as CaCO3), turbidity, temperature, and total dissolved
solids (IDS). The monitoring results shall be reported on the facility's Discharge Monitoring Reports and
included with the NPDES permit renewal application.
A (25.) BIOCIDE CONDITION
[NCGS 143-215.1]
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. (26.) 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 26 of 26

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Facility Information Facility
Outfall 002 Latitude: 36°32'03" Sub-Basin: 03-02-05 I
Location
Outfall 002 Longitude:78°53'27" Permit: NC0038377
Quad Name: Cluster Springs,A23SW
Stream Class: WS-V
Progress Enerry Carolinas,Inc.
Mayo Electric Generating Plant Stream: Mayo Reservoir 1vrO th
Person County