NC0086665_Final Permit_20220804 (2)

DocuSign Envelope ID: 3FA40D0B-49F0-41A0-B4DF-B1A20F3FC9FA
Duke Rockingham NC0086665
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF NATURAL RESOURCES
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
(NPDES)
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 Carolinas, LLC
is hereby authorized to discharge wastewater from a facility located at
Rockingham Combustion Turbine Station
240 Ernest Drive
Reidsville, North Carolina
Rockingham County
to receiving waters designated as an unnamed tributary to Little Jacobs Creek in the Roanoke River Basin
in accordance with effluent limitations, monitoring requirements, and other conditions set forth in Parts I,
II, III, and IV hereof.
The permit shall become effective September 1, 2022
This permit and the authorization to discharge shall expire at midnight on April 30, 2027
Signed this day August 12, 2022
,-DocuSigned by:
Vb4AS POW 1. u
S 57287E56E81 A4OD...
Richard E. Rogers, Jr., Director
Division of Water Resources
By Authority of the Environmental Management Commission
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DocuSign Envelope ID: 3FA40D0B-49F0-41A0-B4DF-B1A20F3FC9FA
Duke Rockingham NC0086665
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility, whether for operation or discharge are hereby
revoked, and as of this 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 described herein.
Duke Energy Carolinas, LLC
is hereby authorized to:
1. continue to operate an existing Surface -Water Pollution Prevention System to treat stormwater, wash -
down water, calibration water, and hydrostatic tank -testing water and similar wastewaters in proximity
to above -ground storage tanks (ASTs) and appurtenant piping where total surface bulk -storage of
petroleum hydrocarbon fuels exceeds one (1) million gallons, utilizing
• oil -water separator
• polishing filter
• discharge line with hand -operated valve (normally closed)
located at Rockingham Combustion Turbine Station, 240 Earnest Drive, Reidsville, Rockingham
County, and
2. discharge from said treatment works via Outfall 001, a location specified on the attached map, into an
unnamed tributary to Little Jacobs Creek [stream segment 22-32-2], currently a Class C waterbody
within Subbasin 03-02-02 [HUC: 03010103] of the Roanoke River Basin.
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DocuSign Envelope ID: 3FA40D0B-49F0-41A0-B4DF-B1A20F3FC9FA
Duke Rockingham
NC0086665
Part I
A. (1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
[15A NCAC 02B .0400 et seq., 02B .0500 et seq.]
Beginning on the effective date of the permit and lasting until expiration, the Permittee is authorized to
discharge from Outfall 001. Such discharges shall be limited, monitored, and reported 1 by the
Permittee as specified below:
EFFLUENT
CHARACTERISTICS
[Parameter Codes]
LIMITS
MONITORING REQUIREMENTS
Monthly
Average
Daily
Maximum
Measurement
Frequency
Sample
Type
Sample
Location
Flow 2
50050
Episodic
Instantaneous
Effluent
Total Suspended Solids
C0530
45.0 mg/L
Monthly
Grab
Effluent
Turbidity
00070
Monthly
Grab
Effluent
Temperature 3
00010
Monthly
Grab
Effluent
Benzene
34030
Annually
Grab
Effluent
Toluene
34010
Annually
Grab
Effluent
Ethylbenzene
34371
Annually
Grab
Effluent
Total Xylenes
81551
Semiannually
Grab
Effluent
WET Testing, Acute 4
TGE6C
Annually 5
Grab
Effluent
Footnotes:
1. The Permittee shall submit Monthly Discharge Monitoring Reports (DMRs) electronically in accord
with the Division's Electronic Discharge Monitoring Reporting (eDMR) Program [section A. (3.)].
2. Flow — During periods of no flow, the Permittee shall submit a monthly Discharge Monitoring
Report (DMR) indicating "No discharge." Flow shall be monitored with each discharge event and
may be monitored using one of the following:
• measure flow continuously
• calculate flow based on total rainfall per area draining to the outfall
• estimate flow at 20-minute intervals during the entire discharge event, or
• report flow based on discharge pump logs.
3. Temperature — Effluent temperature shall not increase the receiving -stream temperature by more
than 2.8 degrees C, nor may it ever cause the receiving -stream temperature to exceed 32 C.
4. Whole Effluent Toxicity (WET) Testing; Acute [TGE6C] using Fathead Minnow (Pimephales
promelas), 24-hour static test at an effluent concentration of 90% during the months of February,
May, August, and November.
5. Annually: Based on a positive compliance record, DWR has previously relaxed the WET -Test frequency
to Annually However, if any WET -test should fail, the Permittee shall immediately revert to Monthly
monitoring until toxicity is resolved [see A. (2.), paragraph #3], and maintain "Quarterly" monitoring for
the remainder of the permit cycle. Thereafter, if five (5) consecutive Quarterly WET -test again indicating
"pass," the Permittee may again petition DWR to relax monitoring, as data may warrant.
Conditions:
1. The Permittee shall discharge no floating solids or foam visible in other than trace amounts.
2. The Permittee shall discharge no tank solids, tank bottom water, or the tank rag layer.
3. Following hydrostatic testing, the Permittee shall discharge no tank (or pipe) contents unless
discharge analyses show Benzene concentration below 1.19µg/L and Toluene concentration
below 11 µg/L.
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DocuSign Envelope ID: 3FA40D0B-49F0-41A0-B4DF-B1A20F3FC9FA
Duke Rockingham NC0086665
A. (2.) ACUTE TOXICITY PASS/FAIL - PERMIT LIMIT (QUARTERLY)
[15A NCAC 02B .0200 et seq.]
The permittee shall conduct acute toxicity tests on a quarterly basis [except when relaxed to Annually] 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 February, May,
August, and November. 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.
Should any single WET test indicate failure to meet specified limits, then Monthly monitoring shall begin
immediately until such time that a single test is passed. Upon passing, this monthly test requirement will revert to
Quarterly during the months specified above.
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/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 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 the permittee fail to monitor during a month in which toxicity monitoring is required, then monthly
monitoring will begin immediately until such time that a single test is passed. Upon passing, this monthly test
requirement will revert to quarterly in the months specified above. Assessment of toxicity compliance is based on
the toxicity testing quarter, which is the three-month time interval that begins on the first day of the month in
which toxicity testing is required by this permit and continues until the final day of the third month.
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.
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DocuSign Envelope ID: 3FA40D0B-49F0-41A0-B4DF-B1A20F3FC9FA
Duke Rockingham NC0086665
A. (3.) ELECTRONIC REPORTING OF DISCHARGE MONITORING REPORTS
[NCGS 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.
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, 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).
2. Electronic Submissions
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DocuSign Envelope ID: 3FA40D0B-49F0-41A0-B4DF-B1A20F3FC9FA
Duke Rockingham NC0086665
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)].
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
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DocuSign Envelope ID: 3FA40D0B-49F0-41A0-B4DF-B1A20F3FC9FA
Duke Rockingham NC0086665
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."
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].
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