NC0024147_Draft Permit_20220920

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
RICHARD E. ROGERS, JR.
Director
NORTH CAROLINA
Environmental Quality
September 20, 2022
Mr. Victor Czar, Public Works Director
City of Sanford
P.O. Box 3729
Sanford, North Carolina 27331-3729
Subject: Draft NPDES Permit Renewal
Permit NC0024147
Big Buffalo WWTP
Lee County
Grade IV Biological WPCS
SIC Code 4952
Dear Mr. Czar:
Enclosed with this letter is a copy of the Draft NPDES permit renewal for your facility. Please
review this draft carefully to ensure thorough understanding of the requirements and conditions it
contains. There are several changes from the existing permit, including the following:
• To aid in calculating total nitrogen and total phosphorus loads, Total Monthly Flow
monitoring has been added to the permit [See A. (1.)].
• Based on NPDES guidance regarding the reduction of monitoring frequencies in NPDES
permits for exceptionally performing facilities, monitoring requirements for CBOD5, Total
Suspended Solids and Fecal Coliform are maintained at twice per week; and NH3-N
monitoring requirements have been reduced to twice per week [See A. (1.)].
• In the event that chlorination is used for disinfection, a Total Residual Chlorine (TRC)
maximum daily limit of 28 µg/L has been added to the permit, to be effective when
chlorination is used [See A. (1.)].
• Based on the reasonable potential analysis (RPA) showing no reasonable potential to violate
state water quality standards, the monitoring requirement for Total Copper has been removed
from the permit [See A. (1.)].
• Based on Mercury TMDL evaluation showing mercury values reported at levels > 1 ng/L
and since the permitted flow is > 2 MGD, Special Condition A. (6.) Mercury Minimization
Plan has been added to the permit.
• Some of the wording has changed in Special Condition A. (2.), Chronic Toxicity Permit
Limit. Please review each paragraph carefully.
• Special Condition A. (3.) has been modified to include the specific three years in which the
Effluent Pollutant Scan shall be performed (2024, 2025, and 2026). In addition, at the end of
NORTH CAROLINA
E,
Department of
M Environmental Quality
North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 11611 Mail Service Center I Raleigh, North Carolina 27699-1611
919.707.9000

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
the Special Condition, some wording in the 2nd species Toxicity Testing Requirements have
been revised; please review it carefully.
• Based on limited dataset from the investigative sampling in 2020 indicating detectable levels,
monthly effluent monitoring for 1,4-Dioxane has been added to the permit [See A. (1.) and
A. (2.)].
• Based on NPDES guidance regarding the reduction of monitoring frequencies in NPDES
permits for exceptionally performing facilities, monitoring requirements for BOD5, Total
Suspended Solids and Fecal Coliform are maintained at twice per week, and monitoring
requirements for Ammonia (NH3-N) has been reduced to twice per week [See A. (1.)].
• A permit reopener special condition has been added to modify 1,4-Dioxane monitoring,
treatment and/or compliance [See A. (12.)].
• A special condition to monitor effluent PFAS chemicals quarterly has been added to the
permit, to be effective six (6) months after EPA has a final wastewater method in 40 CFR136
method published in the Federal Register.
• A notation was made concerning the Electronic Reporting Rule — NPDES Electronic
Reporting Rule — Phase 2 Extension. EPA extended the Phase 2 deadline to December 21,
2025.
The NPDES standard conditions (Parts II, III, and IV) that are a part of the permit are not included
in this draft document (cover, map, and Part I). The conditions are the same as in your current
permit except that agency and division names have been updated. The latest version is available at
https://bit.ly/3k5NFaL and can be viewed online or downloaded as a PDF file.
Concurrent with this notification the Division is publishing a notice in a newspaper having
circulation in the general Lee County area, soliciting public comments on this draft permit.
Please provide any written comments you may have to the following: NCDEQ/DWR, NPDES
Permitting Branch, 1617 Mail Service Center, Raleigh, NC 27699-1617 no later than 30 days
after receipt of this draft permit.
Following the 30-day public comment period, the Division will review all pertinent comments
and take appropriate action prior to issuing a final permit. If you have questions concerning this
draft permit, please call me at [phone] or by email at [e-mail].
Sincerely,
DocuSigned by:
@ etAAMARtie
9FBBBC952DF8455...
Gary Perlmutter, Environmental Specialist II
NPDES Municipal Permitting Unit
Hardcopy: NPDES Files
e-Copy: US EPA Region 4
City of Sandford/ Pretreatment Coordinator/ Sarah Sandford
DWR/Raleigh Regional Office/Water Quality/Scott Vinson
DWR/ Raleigh Regional Office — Pretreatment/ Cheng Zang
DWR/Operator Certification Program/Maureen Kinney
£ D_E
NORTHCAROLINA
Department of Environmental Deal
North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 11611 Mail Service Center I Raleigh, North Carolina 27699-1611
919.707.9000

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
DWR/Ecosystems Branch/Mark Vander Borgh
DWR/Basin Planning/Nora Deamer
DWR/Aquatic Toxicology Branch/ Cindy Moore
DWR/Municipal Permitting Unit//Keyes McGee
£D_E
NORTH CAROLINA
Department of Environmental Duel
North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 11611 Mail Service Center I Raleigh, North Carolina 27699-1611
919.707.9000

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
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,
City of Sanford
is hereby authorized to discharge wastewater from a facility located at the
Big Buffalo Wastewater Treatment Plant
5327 Iron Furnace Road
Sanford, North Carolina
Lee County
to receiving waters designated as Deep River in the Cape Fear River Basin in accordance with effluent
limitations, monitoring requirements, and other conditions set forth in Parts I, II, III, and IV hereof.
This permit shall become effective Month 1, 2022.
This permit and authorization to discharge shall expire at midnight on September 30, 2027.
Signed this day Month xx, 2022.
DRAFT
for Richard E. Rogers, Jr., Director
Division of Water Resources
By Authority of the Environmental Management Commission
Page 1 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
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.
The City of Sanford
is here authorized to:
1. Continue to operate and maintain the wastewater treatment works identified on the Cover, an existing 12.0
MGD facility consisting of the following components:
• Four mechanical bar screens
• One manual bar screen
• Dual grit collection systems
• One equalization tank
• Four BNR basins
• Five clarifiers
• Denitrification filters
• Ultraviolet disinfection system
• Effluent Parshall flume meter
• Reclaimed water distribution system
• Alum and supplemental carbon facility
• Gravity -belt thickeners
• Five sludge storage tanks
• Standby power
2. Discharge from said treatment works at the location specified on the attached map via Outfall 001 into the
Deep River, classified C waters in the Cape Fear River Basin and 03030003 HUC.
Page 2 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
A.(1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS (12.0 MGD)
[15A NCAC 02B .0400 et seq., 15A NCAC 02B .0500 et seq.]
Grade IV Biological Water Pollution Control System [15A NCAC 08G .0302]
(a.) During the period beginning on the effective date of the permit and lasting until permit expiration, the
Permittee is authorized to discharge treated municipal and industrial wastewater from Outfall 001. Such
discharges shall be limited and monitored' by the Permittee as specified below:
PARAMETER
Parameter Code
EFFLUENT LIMITATIONS
MONITORING REQUIREMENTS
Monthly
Average
Weekly
Average
Daily
Maximum
Measurement
Frequency
Sample
Type
Sample
Location'
Flow 50050
12.0 MGD
Continuous
Recording
I or E
Total Monthly Flow, MG 82220
Monitor and Report
Monthly
Recorded
or
Calculated
I or E
CBOD5 (20 7 C) 3
(Apr 1 - Oct 31) 80082
5.0 mg/L
7.5 mg/L
2/week 4
Composite
I & E
CBOD5 20 LJ C 3
(Nov 1 (Mar 31) 80082
9.2 mg/L
14.2 mg/L
2/week 4
Composite
I & E
Total Suspended Solids CO530
30.0 mg/L
45.0 mg/L
2/week 4
Composite
I & E
Ammonia (NH3 as N)
(Apr 1 - Oct 31) CO610
1.0 mg/L
3.0 mg/L
2/week 4
Composite
E
Ammonia (NH3 as N)
(Nov 1 -Mar 31) CO610
1.1 mg/L
3.4 mg/L
2/week 4
Composite
E
Fecal Coliform 31616
(geometric mean)
200/100 mL
400/100 mL
2/week 4
Grab
E
Total
(TRC) Residual Chlorine 50060
28 µg/L
Daily
Grab
E
Dissolved Oxygen (DO) 00300
Daily Average > 5.0 mg/L
Daily
Grab
E
DO, mg/L 00300
Monitor and Report
Variable 2
Grab
U, D
pH 00400
Between 6.0 and 9.0 standard units
Daily
Grab
E
Temperature, °C 00010
Monitor and Report
Daily
Grab
E
Temperature, °C 00010
Monitor and Report
Variable 2
Grab
U, D
Conductivity, mhos/cm 00094
Monitor and Report
Daily
Grab
E
Conductivity, µmhos/cm 00094
Monitor and Report
Variable 2
Grab
U, D
Total Phosphorus (TP), CO665
mg/L
Monitor and Report
Weekly
Composite
E
QM665
TP Load 6
QS665
Monitor and Report (lb/mo)
20,138 lb/summer (Apr 1 — Oct 31)
Monthly
Calculated
E
Seasonally
Calculated
E
Total Nitrogen (TN), CO600
mg/L 7
Monitor and Report
p
WeeklyComposite
p
E
QM600
TN Load 6
QY600
Monitor and Report (lb/mo)
64,628 lb/season (Apr 1 — Oct 31)
Monthly
Calculated
E
Seasonally
Calculated
E
Total Kjeldahl Nitrogen 00625
Monitor and Report
Weekly
Composite
E
(TKN), mg/L
Nitrate/Nitrite Nitrogen 00630
(NO3+NO2), mg/L
Monitor and Report
Weekly
Composite
E
Total Hardness (as 00900
CaCO3), mg/L 8
Monitor and Report
Quarterly
Composite
E
Total Hardness(asas 00900
CaCO3), mg/L
Monitor and Report
Quarterly
Composite
U
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DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
1,4-Dioxane, µg/L 10 82388
Monitor and Report
Monthly
Grab
E
PFAS various
Footnote 11
Quarterly
Grab
E
Chronic Toxicity 12 TGP3B
Monitor and Report
Quarterly
Composite
E
Effluent Pollutant Scan NC01
Monitor and Report
Footnote 13
E
Footnotes:
1. The Permittee shall submit discharge monitoring reports electronically using NC DWR's eDMR application system. See
Special Condition A. (9.).
2. Sample locations: I = Influent; E = Effluent; U = Upstream at Cumnock Bridge; D = Downstream at Highway 15-501.
Upstream and downstream samples shall be collected 3/week during the months of June, July, August, and September,
and weekly during the remainder of the year. Instream sampling requirements are provisionally waived in light of the
permittee's participation in the Upper Cape Fear River Basin Association. Should participation in the association cease,
all instream sampling requirements are immediately reinstated.
3. The monthly average effluent BOD5 and TSS concentrations shall not exceed 15% of the respective influent value (85%
removal).
4. Twice per week sampling must occur on any two non-consecutive days during the calendar week.
5. The facility shall monitor TRC when using chlorination for disinfection. 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.
6. Refer to Special Condition A. (5.), Calculation of Total Nitrogen or Total Phosphorus Loads.
7. For a given wastewater sample, TN = TKN + NO3-N + NO2-N, where TN is Total Nitrogen, TKN is Total Kjeldahl
Nitrogen, and NO3-N and NO2-N are Nitrate and Nitrite Nitrogen, respectively.
8. Effluent hardness sampling should be performed in conjunction with testing for hardness dependent metals (cadmium,
copper, lead, nickel, silver, and zinc).
9. The Permittee shall sample instream hardness upstream of the facility's discharge. The sample shall be representative of
the hardness in the receiving stream.
10. Samples must be reported to a minimum of PQL < 1 µg/L using an appropriate 40 CFR Part 136 method.
11. See Special Condition A. (8.).
12. Chronic Toxicity (Ceriodaphnia) at 45% while testing in March, June, September and December. See Special Condition
A. (2.).
13. The Permittee shall perform three Effluent Pollutant Scans and four second -species effluent toxicity tests during the term
of this permit. See Special Condition A. (3.).
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 4 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
A.(2.) FRESHWATER CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY)
[15A NCAC 02B.0200] [15A NCAC 02B .0500 et seq.]
The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant mortality to
Ceriodaphnia dubia at an effluent concentration of 45%.
The permit holder shall perform at a minimum, quarterly monitoring using test procedures outlined in the "North
Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure," (Revised December 2010, or subsequent versions)
or "North Carolina Phase II Chronic Whole Effluent Toxicity Test Procedure" (Revised December 2010, or
subsequent versions). 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.
If the test procedure performed as the first test of any single quarter results in a failure or Chronic Value
(ChV) below the permit limit, then multiple -concentration testing shall be performed at a minimum, in
each of the two following months as described in "North Carolina Phase II Chronic Whole Effluent
Toxicity Test Procedure" (Revised -December 2010, or subsequent versions).
All toxicity testing results required as part of this permit condition will be entered electronically using the
Division's eDMR system for the months in which tests were performed, using the parameter code TGP3B for the
pass/fail results and THP3B for the Chronic Value. Additionally, DWR Form AT-3 (original) is to be sent to the
following address:
North Carolina Division of Water Resources
Water Sciences Section/Aquatic Toxicology Branch
1621 Mail Service Center
Raleigh, NC 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, accurate, include all supporting chemical/physical measurements and all
concentration/response data, and be certified by laboratory supervisor and ORC or approved designate signature.
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, monitoring will be
required during the following month. 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 this monitoring requirement 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.
Page 5 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
If the Permittee monitors any pollutant more frequently than required by this permit, the results of such
monitoring shall be included in the calculation & reporting of the data submitted on the DMR & all AT Form
submitted.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum control organism
survival, minimum control organism reproduction, 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 6 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
A.(3.) ADDITIONAL MONITORING REQUIREMENTS FOR PERMIT RENEWAL
[NCGS 143-215.1(b)]
(a.) Effluent Pollutant Scans. The permittee shall perform a total of three (3) Effluent Pollutant Scans for all
parameters listed below. One scan must be performed in each of the following years: 2024, 2025, and
2026. Analytical methods shall be in accordance with 40 CFR Part 136 and shall be sufficiently sensitive to
determine whether parameters are present in concentrations greater than applicable standards and criteria.
Each annual sample shall coincide with one quarterly toxicity test each year [see Condition A.(2.)
FRESHWATER CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY)], and each must be collected in
a different calendar quarter to represent seasonal variation [i.e., do not sample in the same quarter every
year]. Unless otherwise indicated, metals shall be analyzed as "total recoverable."
Ammonia (as N)
Chlorine (total residual, TRC)
Dissolved oxygen
Nitrate / Nitrite
Kjeldahl nitrogen
Oil and grease
Phosphorus
Total dissolved solids
Hardness
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Copper
Lead
Mercury (Method 1631E)
Nickel
Selenium
Silver
Thallium
Zinc
Cyanide
Total phenolic compounds
Volatile organic compounds:
Acrolein
Acrylonitrile
Benzene
Bromoform
Carbon tetrachloride
Chlorobenzene
Chlorodibromomethane
Chloroethane
2-chloroethyl vinyl ether
Chloroform
Dichlorobromomethane
1,1-dichloroethane
1,2-dichloroethane
C0610 Trans-1,2-dichloroethylene
50060 1,1-dichloroethylene
00300 1,2-dichloropropane
00630 1,3-dichloropropylene
00625 Ethylbenzene
00556 Methyl bromide
C0665 Methyl chloride
70295 Methylene chloride
00900 1,1,2,2-tetrachloroethane
01097 Tetrachloroethylene
01002 Toluene
01012 1,1,1-trichloroethane
01027 1,1,2-trichloroethane
C0034 Trichloroethylene
01042 Vinyl chloride
01051 Acid -extractable compounds:
COMER P-chloro-m-cresol
01067 2-chlorophenol
01147 2,4-dichlorophenol
01077 2,4-dimethylphenol
01059 4,6-dinitro-o-cresol
01092 2,4-dinitrophenol
00720 2-nitrophenol
32730 4-nitrophenol
Pentachlorophenol
34210 Phenol
34215 2,4,6-trichlorophenol
34030 Base -neutral compounds:
32104 Acenaphthene
32102 Acenaphthylene
34301 Anthracene
34306 Benzidine
85811 Benzo(a)anthracene
34576 Benzo(a)pyrene
32106 3,4 benzofluoranthene
32101 Benzo(ghi)perylene
34496 Benzo(k)fluoranthene
32103 Bis (2-chloroethoxy) methane
34546
34501
C0541
77163
34371
34413
34418
34423
81549
34475
34010
34506
34511
39180
39175
34452
34586
34601
34606
34657
34616
34591
34646
39032
34694
34621
34205
34200
CO220
39120
C0526
34247
34230
34521
34242
34278
Bis (2-chloroethyl) ether
Bis (2-chloroisopropyl) ether
Bis (2-ethylhexyl) phthalate
4-bromophenyl phenyl ether
Butyl benzyl phthalate
2-chloronaphthalene
4-chlorophenyl phenyl ether
Chrysene
Di-n-butyl phthalate
Di-n-octyl phthalate
Dibenzo(a,h)anthracene
1,2-dichlorobenzene
1,3-dichlorobenzene
1,4-dichlorobenzene
3,3-dichlorobenzidine
Diethyl phthalate
Dimethyl phthalate
2,4-dinitrotoluene
2,6-dinitrotoluene
1,2-diphenylhydrazine
Fluoranthene
Fluorene
Hexachlorobenzene
Hexachlorobutadiene
Hexachlorocyclo-pentadiene
Hexachloroethane
Indeno(1,2,3-cd)pyrene
Isophorone
Naphthalene
Nitrobenzene
N-nitrosodi-n-propylamine
N-nitrosodimethylamine
N-nitrosodiphenylamine
Phenanthrene
Pyrene
1,2,4-trichlorobenzene
34273
34283
C0100
34636
34292
34581
34641
34320
39110
34596
34556
34536
34566
34571
34631
34336
34341
34611
C0626
34346
C0376
34381
C0700
C0702
34386
34396
34403
34408
34696
34447
34428
34438
34433
34461
34469
C0551
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DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
(b.) Effluent Scan Reporting. Test results shall be reported electronically via eDMR by December 31st of
each designated sampling year, except that, subject to prior written approval by the Director, results can be
reported on DWR Form DMR-PPA-1 or other form approved by the Director. The permittee must at least
report completion of the test in the eDMR system by entering "1" or "Y" for parameter code NC01 -
Annual Pollutant Scan. If written reports are approved, the report shall be submitted to the following
address:
North Carolina Division of Water Resources
Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Or the form may be uploaded at: https://edocs.deq.nc.gov/Forms/NPDES WW-EDMR-Supplemental-Form
(c.) 2nd-Species Toxicity Testing and Reporting.
(i.)
In addition to the quarterly toxicity tests required in Condition A.(2.) FRESHWATER CHRONIC
TOXICITY PERMIT LIMIT (QUARTERLY)], the Permittee shall perform and report the results of
four (4) toxicity tests using the same test methods using a second species of test organism suitable to
the tests being conducted.
(ii.) The 2nd species toxicity tests shall be conducted either:
(A) Once per quarter in a single 12-month period (four samples); if this option is chosen, the
sample for each 2nd species test shall coincide with the quarterly samples collected for (tox
condition title); or
(B) Once per 12-month period in the four -and one-half year period prior to the scheduled
application for permit renewal (four samples); if this option is chosen, three of the sample for
the 2nd species test shall coincide with those for the annual effluent scans and the coincident
quarterly toxicity test, and each of the four annual samples shall be collected in a different
calendar quarter in order to represent seasonal variation.
(iii.) The results of the toxicity tests shall be submitted to the following address:
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].
(iv.) Results of the 2nd species tests shall also be summarized in Part E (Toxicity Testing Data) of EPA
Municipal Application Form 2A when submitting the permit renewal application to the NPDES
Wastewater Program.
The Permittee may contact the Division's Aquatic Toxicology Branch at 919-743-8401 for guidance
on conducting the additional toxicity tests and reporting of the results.
Page 8 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
A.(4.) NUTRIENT MONITORING REOPENER [NCGS 143-215.1(b)]
Pursuant to N.C. General Statute Section 143-215.1 and the implementing rules found in Title 15A of the North
Carolina Administrative Code, Subchapter 2H, specifically, 15A NCAC 2H.0112(b) (1) and 2H.0114(a), and Part
II, Sections B-12 and B-13 of this permit, the Director of DWQ may reopen this permit to require supplemental
nutrient monitoring of the discharge. The additional monitoring will be to support water quality modeling efforts
within the Cape Fear River Basin and shall be consistent with a monitoring plan developed jointly by the Division
and affected stakeholders.
A.(5.) CALCULATION OF TOTAL NITROGEN OR TOTAL PHOSPHORUS LOADS
[15A NCAC 02B .0270]
(c.) The Permittee shall calculate monthly and annual TN (or TP) Loads as follows:
(i.) Monthly TN (or TP) Load (lb/mo) = TN (or TP) x TMF x 8.34
where:
TN or TP = the average Total Nitrogen or Total Phosphorus concentration (mg/L) of
the composite samples collected during the month;
TMF = the Total Monthly Flow of wastewater discharged during the month
(MG/mo);
8.34 conversion factor, from (mg/L x MG) to pounds.
(ii.) Annual TN (or TP) Load (lb/yr) = Sum of the 12 Monthly TN (or TP) Loads for the calendar year
(d.) The Permittee shall report monthly Total Nitrogen and Total Phosphorus results (mg/L and lb/mo) in the
appropriate discharge monitoring report for each month and shall report each calendar year's results (1b/yr)
with the December report for that year.
A. (6.) MERCURY MINIMIZATION PLAN [NCGS 143-215.1(b)]
The Permittee shall develop and implement a Mercury Minimization Plan (MMP) during this permit term. The
MMP shall be developed within 180 days from the Permit Effective Date and shall be available for inspection on -
site. A sample MMP was developed through a stakeholder review process and has been placed on the Division
website for guidance (http://deq.nc.gov/about/divisions/water-resources/water-resources-permits/wastewater-
branch/npdes-wastewater-permits, under Model Mercury Minimization Plan). The MMP should place emphasis
on identification of mercury contributors and goals for reduction. Results shall be summarized and submitted with
the next permit renewal. Performance of the Mercury Minimization Plan will meet the requirements of the TMDL
(Total Maximum Daily Load) for mercury approved by USEPA on October 12, 2012, unless and until a Waste
Load Allocation specific to this facility is developed and this NPDES permit is amended to require further actions
to address the Waste Load Allocation.
Page 9 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
A. (7.) REOPENER FOR 1,4-DIOXANE [NCGS 143-215.1 (b)]
Pursuant to N.C. General Statutes Section 143-215.1 and the implementing rules found in the North Carolina
Administrative Code at 15A NCAC 2H.0112 (b) (1) and 2H.0114 (a) and Part II, Sections B-12 and B-13 of this
permit, the Director of DWR may reopen this permit to modify permit requirements to address 1,4-Dioxane
monitoring, treatment and/or compliance.
A. (8.) PFAS MONITORING REQUIREMENT [NCGS 143-215.1(b)]
This reporting requirement for the per- and polyfluoroalkyl substances (PFAS) parameters listed under Table 1 of
the Final Method 1633 takes effect the first full calendar quarter following six (6) months after EPA publishes a
40 CFR part 136 Final PFAS Method for wastewater in the Federal Register. Monitoring will be at a quarterly
frequency.
Find the current parameters listed under Table 1 of the August 2021 Draft Method 1633 Analysis of Per- and
Polyfluoroalkyl Substances (PFAS) in Aqueous, Solid, Biosolids, and Tissue Samples by LC-MS/MS at:
https://www.epa.gov/system/files/documents/2021-09/method_1633_draft aug-2021.pdf
A.(9.) 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)1
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
monthly electronically using eDMR. The eDMR system allows permitted facilities to enter monitoring data
and submit monthly DMRs electronically using the internet. The eDMR system may be accessed at:
https://deq.nc.gov/about/divisions/water-resources/edmr.
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 following address:
Page 10 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
NC Division of Water Resources/Water Quality Permitting Section
ATTENTION: Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
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
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:
https://www.federalregister.gov/documents/2015/ 10/22/2015-24954/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 five (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.
Page 11 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
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)1
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 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 three (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].
Page 12 of 13

DocuSign Envelope ID: E095F9D4-F6FD-41F9-902A-66F7FBD2FC2B
Permit No. NC0024147
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Page 13 of 13