NC0021156_Issuance of Permit_20240409 (2)

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F81B3CDFD7F
ROY COOPER
Governor
ELIZABETH S. BISER
Secretory
RICHARD E. ROGERS, JR.
Director
Mr. Danny Jackson, City Manager
City of Mount Holly
P.O. Box 406
Mount Holly, North Carolina 28120
Dear Mr. Jackson:
NORTH CAROLINA
Environmental Quality
April 9, 2024
Subject: Final NPDES Permit Renewal
Permit NCO021156
Mount Holly WWTP
Gaston County
Grade IV Biological WPCS
SIC Code 4952
Division personnel have reviewed and approved your application for renewal of the subject permit.
Accordingly, we are forwarding the attached NPDES permit. This permit is issued pursuant to the
requirements of North Carolina General Statute 143-215.1 and the Memorandum of Agreement between
North Carolina and the U.S. Environmental Protection Agency dated October 15, 2007 (or as subsequently
amended).
No changes were made to the draft permit sent to you on February 20, 2024. The final permit
maintains the significant changes made to the draft permit sent to you on February 20, 2024.
• Based on WLA-calculated allowable concentrations to protect the receiving stream against ammonia
toxicity and review of effluent data in comparison, monthly average limits of 13.0 mg/L (summer) and
26.0 mg/L (winter) plus a year-round weekly average limit of 35 mg/L have been added to the permit
[See A.(1.)].
• Based on a Reasonable Potential Analysis (RPA) resulting in finding a reasonable potential to exceed
instream water quality standards (RP), limits for Total Copper and Total Silver have been added to the
permit [See A.(1.)].
• To provide an opportunity for the City to develop a plan to assess Total Silver in order to come into
compliance with the limits in Section A.(1.), a three-year compliance schedule with the alternative of
discharge cessation has been added to the permit [See Special Condition A.(8.)].
• Based on the RPA not resulting in RP but the maximum predicted value is found to be > 50% of the
allowable concentration, quarterly monitoring for Total Cyanide has been added to the permit.
• Based on the facility receiving industrial waste through a Division -approved pretreatment program,
daily Conductivity monitoring has been added to the permit.
• Based on the facility receiving industrial wastewater from industry types recognized as potential
sources of 1,4-Dioxane, quarterly monitoring for 1,4-Dioxane with a permit reopener condition has
been added to the permit [See A.(9.)].
D E Q North Carolina Department ofEnvironmental Quality I Division of Water Resources
512 North Salisbury Street 1 1611 Mail Service Center I Raleigh, North Carolina 27699-1611
y.w,� 919.707.9000

DocuSign Envelope ID. 87A95731-0639-4727-ADFE-5F81B3CDFD7F
• To assess industrial contributions of PFAS chemicals to the Mount Holly WWTP and assess levels in
the facility effluent, Special Condition A.(10.) 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 (if the facility is still discharging) shall be performed (2026, 2027, and 2028) if the
facility continues to discharge. In addition, at the end of the Special Condition, 2nd species Toxicity
Testing Requirements for municipal permit renewals per Federal Regulations [40 CFR 122.210)(5)]
have been added.
• 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.
• Federal regulations require electronic submittal of all discharge monitoring reports (DMRs) and
program reports. The requirement to continue reporting discharge monitoring data electronically using
the NC DWR's Electronic Discharge Monitoring Report (eDMR) internet application has been added
to your NPDES permit [See Special Condition A.(11.)].
• To notify the Division of the City's plans regarding closure and transfer of flow from the Mount Holly
WWTP, including pretreatment responsibilities, a Facility Closure Requirements special condition has
been added to the permit [See A.(12.)].
If any parts, measurement frequencies or sampling requirements contained in this permit are unacceptable
to you, you have the right to an adjudicatory hearing upon written request within thirty (30) days following
receipt of this letter. This request must be in the form of a written petition, conforming to Chapter 150B of
the North Carolina General Statutes, and filed with the Office of Administrative Hearings (6714 Mail
Service Center, Raleigh, North Carolina 27699-6714). Unless such demand is made, this decision shall be
final and binding.
Pretreatment updates in response to NPDES permit renewal:
• On October 28, 2024, 180 days after the effective date of this NPDES permit renewal, the City is
required to submit to the Division a written technical evaluation of the need to revise local limits
(i.e., an updated IWS/HWA-AT/L-STMP, or documentation of why is not needed). This action
may include revising, updating, or adding to the list of SIUs regardless of timeframe.
o Submit the updated Long -Term Monitoring Plan (LTMP)
■ If there are new industries within the service area, submit an updated Industrial
Waste Survey (IWS)
■ Review pollutants of concern (POCs) and update the LTMP to reflect pollutants
in industrial user permits (IUPs) and sludge management permit.
o As part of the local limits assessment, please submit the updated Headworks Analysis
(HWA).
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.
Please note that this permit is not transferable except after notice to the Division. The Division may require
modification or revocation and reissuance of the permit. This permit does not affect the legal requirements
to obtain other permits which may be required by the Division of Water Resources or any other Federal,
State, or Local governmental regulations.
E Q�� North Carolina Department of Em vonmental Quality I Division of Water Resources
4NQR��C512 North Salisbury Street 1 1611 Mail Service Center I Raleigh. North Carolina 27699-1611
raaTH d IRnWA n
o.,.a�rrMFwnronbl OuM� /`� 919.707.9000

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F81B3CDFD7F
If you have any questions concerning this permit, please contact Gary Perlmutter at [phone] or via
email at [e-mail].
Sincerely, DocuSigned by:
[Awt,(. Wh
,u,eu�...
Michael J. Montebello, NPDES Permitting Branch Chief
Division of Water Resources, NCDEQ
Hardcopy: NPDES Files
eCopy: US EPA Region 4
DWR / Mooresville Regional Office / Water Quality / Andrew Pitner
DWR / Aquatic Toxicology Branch / Cindy Moore & Molly Nicholson
DWR / Municipal Permitting Unit / Keyes McGee
City of Mount Holly / Keith Lynch (ORC)
SCDHEC / Domestic Wastewater Permitting / Brenda Green
North Carolina Department of Environmental Quality I Division of Water Resources
D E Q/) 512 North Salisbury Street 1 1611 Mail Service Center I Raleigh, North Carolina 27699-1611
919.707.9000
Doytmmt of Fmirommbl OwM�

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F81B3CDFD7F
NCO021156
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WATER 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, the
City of Mount Holly
is hereby authorized to discharge wastewater from a facility located at the
Mount Holly Wastewater Treatment Plant
165 Broome Street
Mount Holly
Gaston County
to receiving waters designated as the Catawba River in the Catawba River Basin
in accordance with the effluent limitations, monitoring requirements, and other applicable conditions set
forth in Parts I, II, III, and IV hereof.
This permit shall become effective May 1, 2024.
This permit and authorization to discharge shall expire at midnight on February 28, 2029.
Signed this day, April 9, 2024.
CA
DocuSgnW by:
� kh��
C484537431644FE...
Michael J. Montebello, NPDES Permitting Branch Chief
Division of Water Resources
Page 1 of 21

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F81B3CDFD7F
NC0021156
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility, whether for operation or discharge are hereby
revoked. As of the effective date 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 Mount Holly
is hereby authorized to:
1. Continue to operate and maintain the wastewater treatment works identified on the Cover, an existing
4.0 MGD facility consisting of the following components:
• Two (2) manually cleaned influent bar screens
• Parshall flume meter system
• One (1) automatic drum screen
• Two (2) grit chambers
• Influent flow meter
• Influent composite sampler
• One (1) 2-MG flow equalization basin with pumps
• Two (2) 2-MG aeration basins with four (4) mechanical aerators per basin
• One (1) 4-MG aeration basin with five (5) mechanical aerators (not in use)
• Two (2) 75-ft diameter secondary clarifiers with RAS/WAS pumps
• Two (2) 35-ft diameter chlorine contact chambers with gas chlorination
• Gas dechlorination system with feed points to each contact chamber
• Effluent meters exit each contact chamber/recorder
• Effluent composite sampler
• Two (2) 0.75-MG aerobic sludge holding tanks with blowers and decant pump
• One (1) 37-ft diameter digester tank (not in use)
• Two (2) sludge holding tanks (not in use — formerly 60-ft diameter clarifiers)
• Two (2) 40 x 30 ft sludge drying beds (not in use)
2. Discharge from said treatment works at the location specified on the attached map via Outfall 001 into
the Catawba River classified WS-IV; CA waters in the Catawba River Basin and 03050101 HUC.
Page 2 of 21

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F81B3CDFD7F
NCO021156
PART
A.(1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS [4.0 MGD]
[15A NCAC 02B .0400 et seq., 15A NCACO2B .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 LIMITS
MONITORING REQUIREMENTS
Monthly
Average
Weekly
Average
Daily
Maximum
Measurement
Frequency
Sample
Type
Sample
Location'
Flow 50050
4.0 MGD
Continuous
Recording
I or E
Total Monthly Flow (MG) 82220
Monitor and Report
Monthly
Calculated
I or E
BOD, 5-day, 20°C 3 C0310
30.0 mg/L
45.0 mg/L
Daily
Composite
I and E
Total Suspended Solids (TSS) 3 C0530
30.0 mg/L
45.0 mg/L
Daily
Composite
I and E
Ammonia (NHS as N) C0610
(Apr 1- Oct 31)
13.0 mg/L
35 mg/L
3/week
Composite
E
Ammonia (Nfb as N) C0610
(Nov 1 - Mar 31)
26.0 mg/L
35 mg/L
3/week
Composite
E
Fecal Coliform 31616
(geometric mean)
200/100 mL
400/100 mL
Daily
Grab
E
Total Residual Chlorine (TRC)4 50060
28 µg/L
Daily
Grab
E
Dissolved Oxygen (DO) 00300
Daily Average >_ 5.0 mg/L
Daily
Grab
E
Temperature (°C) 00010
Monitor and Report
Daily
Grab
E
pH 00400
Between 6.0 and 9.0 Standard Units
Daily
Grab
E
Conductivity (µmhos/cm) 00094
Monitor and Report
Daily
Grab
E
TKN (mg/L) 00625
Monitor and Report
Weekly
Composite
E
NO3-N + NO2-N (mg/L) 00630
Monitor and Report
Weekly
Composite
E
Total Nitrogen (TN) S (mg/L) C0600
Monitor and Report
Weekly
Calculated
E
TN Load 6 (lb/mo) QM600
Monitor and Report
Monthly
Calculated
E
TN Load 6'' QS600
111,973 lb/summer
124,345 lb/winter
Seasonally
Calculated
E
Total Phosphorus (TP) (mg/L) C0665
Monitor and Report
Weekly
Calculated
E
TP Load 6 (lb/mo) QM665
Monitor and Report
Monthly
Calculated
E
TP Load OX QY665
31,405 lb/yr
Annually
Calculated
E
Total Hardness (as CaCO3) a 00900
(mg/L)
Monitor and Report
Quarterly
Composite
E
Total Copper 01042
129 µg/L 141 µg/L
Monthly
Composite
E
Total Cyanide 9 (mg(L) 00720
Monitor and Report
Quarterly
Grab
E
Total Silver 10 01077
0.98 µg/L
1 4.0 µg/L
Monthly
Composite
E
1,4-Dioxane 11 82388
Monitor and Report
Quarterly
Grab
E
PFAS 12 (ng/L) various
Monitor and Report
Quarterly 12
Grab
E
Chronic Toxicity 13 TGP3B
Monitor and Report
Quarterly
Composite
E
Effluent Pollutant Scan 14 NCO]
Monitor and Report
Footnote 14
Footnote 14
E
Page 3 of 21

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F8lB3CDFD7F
NCO021156
EFFLUENT LIMITS
MONITORING REQGIRENIENTS
PARAMETER
Monthly
Weekly
Daily
Measurement
Sample
Sample
Parameter Code
Average
Average
Maximum
Frequency
Type
Location'
Total Hardness (as CaCO3)' ` 00900
Monitor and Report
Quarterly
Grab
U
(mg/L)
Dissolved Oxygen (mg/L) 00300
Monitor and Report
Variable'
Grab
U and D
Temperature °C 00010
Monitor and Report
Variable'
Grab
U and D
Conductivity (µmhos/cm) 00094
Monitor and Report
Variable'
Grab
U and D
Footnotes:
1. The Permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR application
system. See Special Condition A.(11.).
2. Sample locations I = Influent; E = Effluent; U = Upstream at NC Hwy 27 bridge; D = Downstream just below
NC Hwy 29/74 bridge. Upstream and downstream samples shall be grab samples collected 3/week during
June, July, August, and September and 1 /week during the remainder of the year.
3. The monthly average effluent BOD5 and TSS concentrations shall not exceed 15% of the respective influent
value (85% removal).
4. 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.
5. 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.
6. TN or TP Load is the mass quantity of Total Nitrogen or Total Phosphorus discharged in a given period of
time. See Special Condition A. (6.), Calculation of TN or TP Loads.
7. Load limits are based on allocations; see Special Condition A.(4.) Nutrient Allocation, and A.(5.) Total
Nitrogen and Total Phosphorus Limits.
8. Effluent Total Hardness sampling shall be conducted in conjunction with testing for hardness -dependent
metals (cadmium, chromium, copper, lead, nickel, silver, and zinc).
9. The Division shall consider all values reported below 10 µg/L to be "compliant" with this permit. However,
the Permittee shall submit to DWR all values reported by a North Carolina -certified test method (even if
values fall below 10 µg/L), and the Permittee shall consider all reported values when calculating averages, if
any, as required under this permit.
10. The Permittee shall achieve compliance with these limitations within three years of the effective date of this
permit and shall follow the Total Silver compliance schedule detailed in Special Condition A.(8.) or cease
discharge. Starting on the effective date of this permit, the Permittee shall perform monthly effluent
Monitoring and Reporting for Total Silver.
11. Samples shall be analyzed and reported using sufficiently sensitive test procedures (i.e., methods) approved
under 40 CFR Part 136 for the analysis of pollutants or pollutant parameters.
12. Follow Special Condition A.(10.).
13. Whole Effluent Toxicity will be monitored using the Pass/Fail Chronic Toxicity test with Ceriodaphnia dubia
at 6% effluent. Samples shall be collected in February, May, August, and November; see Section A.(2.).
14. The Permittee shall perform three effluent pollution scans during the term of this permit. See Special
Condition A.(3.).
15. The Permittee shall sample instream hardness upstream of the facility's discharge. The sample shall be
representative of the hardness in the stream.
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 4 of 21

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F81B3CDFD7F
NC0021156
A.(2.) CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY)
[15A NCAC 02B .0200, .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 6%.
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
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.
If the test procedure performed as the first test of any single quarter results in a failure or 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 H 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 TGP313
for the pass/fail results and THP311 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.
Page 5 of 21

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F81B3CDFD7F
NC0021156
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.
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 21

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F81B3CDFD7F
NCO021156
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: 2026,
2027, and 2028. 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 tonicity test
each year [see Condition A.(2.) Chronic Toxicity Permit Limit], 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) C0610 Trans-1,2-dichloroethylene 34546 Bis (2-chloroethyl) ether
Chlorine (total residual, TRC) 50060 1, 1 -dichloroethylene 34501 Bis (2-chloroisopropyl) ether
Dissolved oxygen 00300 1,2-dichloropropane C0541 Bis (2-ethylhexyl) phthalate
Nitrate / Nitrite 00630 1,3-dichloropropylene 77163 4-bromophenyl phenyl ether
Kjeldahl nitrogen 00625 Ethylbenzene 34371 Butyl benzyl phthalate
Oil and grease 00556 Methyl bromide 34413 2-chloronaphthalene
Phosphorus
C0665
Methyl chloride
34418
4-chlorophenyl phenyl ether
Total dissolved solids
70295
Methylene chloride
34423
Chrysene
Hardness
00900
1,1,2,2-tetrachloroethane
81549
Di-n-butyl phthalate
Antimony
01097
Tetrachloroethylene
34475
Di-n-octyl phthalate
Arsenic
01002
Toluene
34010
Dibenzo(a h)anthracene
Beryllium
01012
1, 1, 1 -trichloroethane
34506
1,2-dichlorobenzene
Cadmium
01027
1,1,2-trichloroethane
34511
1,3-dichlorobenzene
Chromium
C0034
Trichloroethylene
39180
1,4-dichlorobenzene
Copper
01042
Vinyl chloride
39175
3,3-dichlorobenzidine
Lead
01051
Acid -extractable compounds:
Diethyl phthalate
Mercury (Method 1631E)
COMER
P-chloro-m-cresol
34452
Dimethyl phthalate
Nickel
01067
2-chlorophenol
34586
2,4-dinitrotoluene
Selenium
01147
2,4-dichlorophenol
34601
2,6-dinitrotoluene
Silver
01077
2,4-dimethylphenol
34606
1,2-diphenylhydrazine
Thallium
01059
4,6-dinitro-o-cresol
34657
Fluoranthene
Zinc
01092
2,4-dinitrophenol
34616
Fluorene
Cyanide
00710
2-nitrophenol
34591
Hexachlorobenzene
Total phenolic compounds
32730
4-nitrophenol
34646
Hexachlorobutadiene
Volatile oreanic compounds:
Pentachlorophenol
39032
Hexachlorocyclo-pentadiene
Acrolein
34210
Phenol
34694
Hexachloroethane
Acrylonitrile
34215
2,4,6-trichlorophenol
34621
Indeno(1,2,3-cd)pyrene
Benzene
34030
Base -neutral compounds:
Isophorone
Bromoform
32104
Acenaphthene
34205
Naphthalene
Carbon tetrachloride
32102
Acenaphthylene
34200
Nitrobenzene
Chlorobenzene
34301
Anthracene
CO220
N-nitrosodi-n-propylamine
Chlorodibromomethane
34306
Benzidine
39120
N-nitrosodimethylamine
Chloroethane
85811
Benzo(a)anthracene
C0526
N-nitrosodiphenylamine
2-chloroethyl vinyl ether
34576
Benzo(a)pyrene
34247
Phenanthrene
Chloroform
32106
3,4 benzofluoranthene
34230
Pyrene
Dichlorobromomethane
32101
Benzo(ghi)perylene
34521
1,2,4-trichlorobenzene
1, 1 -dichloroethane
34496
Benzo(k)fluoranthene
34242
1,2-dichloroethane
32103
Bis (2-chloroethoxy) methane
34278
Page 7 of 21
34273
34283
CO100
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

DocuSign Envelope ID: 87A95731-0639-4727-ADFE-5F81B3CDFD7F
NC0021156
(b.) Effluent Scan Resorting. Test results shall be reported electronically via eDMR by December 31 st
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 NCO - 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/Fonns/NPDES—WW-EDMR-Supplemental-Form
(c.) 2,d-Species Toxicity Testing and Reporting.
(i.) In addition to the quarterly toxicity tests required in Condition A.(2.) Chronic Toxicity Permit
Limit, 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 2°d 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
A.(2.) Chronic Toxicity Permit Limit; 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
samples 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.
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A.(4.) NUTRIENT ALLOCATIONS
[NCGS 143-215.1 (b.)]
(a.) The following table list the Total Nitrogen (TN) and Total Phosphorus (TP) allocations assigned to,
acquired by, or transferred to the Permittee in accordance with the 1995 Lake Wylie TMDL and
nutrient management strategy and the status of each as of permit issuance. For compliance purposes,
this table does not supersede any TN or TP limit established elsewhere in this permit.
Total Nitrogen Allocation
DISCHARGE
DISCHARGE
ALLOCATION
SOURCE
DATE
ALLOCATION
ALLOCATION
STATUS
TYPE
SUMMER,
WINTER,
Base
TMDL
1995
64,251lb/season
90,672lb/yr
Active
Transfer by
Supplemental
agreement from
5/3/2018
47,722 lb/season
33,673 Ib/yr
Active
City of Charlotte
Total Allocation
1111,973 lb/season
1124,345 Ib/yr
IActive
Footnote:
1. Summer is defined as April 1 — October 31. Winter is defined as November 1 — March 31.
Total Phosphorus Allocation
ALLOCATION
DISCHARGE
TYPE
SOURCE
DATE
ALLOCATION
STATUS
ANNUAL'
Base
TMDL
1995
18,265lb/yr
Active
Transfer by
Supplemental
agreement from
5/3/2018
13,140 Ib/yr
Active
City of Charlotte
Total Allocation
31,405 Ib/yr
Active
Footnote:
1. Annual means on a calendar year basis, January 1 — December 31.
(b.) Any addition, deletion, or modification of the listed allocation(s) (other than to correct typographical
errors) or any change in status of any of the listed allocations shall be considered a major modification
of this permit and shall be subject to the public review process afforded such modifications under
state and federal rules.
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A.(5.) TOTAL NITROGEN AND TOTAL PHOSPHORUS LIMITS
[NCGS 143-215.1 (b.)]
(a.) Total Nitrogen (TN) allocations and load limits for NPDES dischargers in the Lake Wylie watershed
are seasonal (summer and winter) values. Summer is defined as April 1 through October 31, and
winter is defined as November 1 through March 31. Total Phosphorus (TP) allocations and load limits
are annual values and apply on a calendar year basis, January 1 through December 31.
(b.) The TN (or TP) Load limit in this Permit may be modified as the result of allowable changes in the
Permittee's allocation.
(i.) Allowable changes include those transfers resulting from the purchase, sale, trade, or lease of
allocation between the Permittee and other dischargers assigned allocation under the 1995 Lake
Wylie TMDL; regionalization (if both facilities were assigned allocation); and other
transactions approved by the Division.
(ii.) The Permittee may request a modification of the TN (or TP) Load limit in this Permit to reflect
allowable changes in its allocation.
(A) The request must include an analysis demonstrating that change in allocations and limits
does not have a reasonable potential to cause localized water quality impacts.
(B) Upon receipt of timely and proper application, the Division will propose to modify the
permit as appropriate and in accordance with state and federal program requirements.
(C) Changes in TN or TP limits become effective on the first January 1 (annual limit), the
first April 1 (summer limit), or the first November 1 (winter limit) following permit
modification. The Division must receive application no later than 180 days prior to the
requested effective date for any limit change.
(iii.) Any requests for modification should be sent to:
North Carolina Division of Water Resources
NPDES Programs
1617 Mail Service Center
Raleigh, NC 27699-1617
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A.(6.) CALCULATION AND REPORTING OF TOTAL NITROGEN AND TOTAL
PHOSPHORUS LOADS
[NCGS 143-215.1 (b.)]
(a.) The Permittee shall calculate monthly, seasonal, 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:
U
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); that is, the sum of daily flows in the month
8.34 = conversion factor, from (mg/L x MG) to pounds
(ii.) Summer TN Load (lb/summer) = Sum of the April —October Monthly TN Loads for the
season;
(iii.) Winter TN Load (lb/winter) = Sum of the November —March Monthly TN Loads for the
season;
(iv.) Annual TP Load (lb/yr) = Sum of the 12 Monthly TP Loads for the calendar year.
(b.) 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: the summer TN results with the October
DMR; the winter TN results with the March DMR; and each calendar year's results with the
December report for that year.
(c.) Any addition, deletion, or modification of the listed allocation(s) (other than to correct typographical
errors) or any change in status of any ofthe listed allocations shall be considered a major modification
of this permit and shall be subject to the public review process afforded such modifications under
state and federal rules.
A.(7.) MERCURY MINIMIZATION PLAN (MMP) [NCGS 143- 215.1 (b.)]
The Permittee shall maintain and continue to implement the Mercury Minimization Plan (MMP) developed
in the previous permit term. The MMP shall continue to be available for inspection on -site. 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 MMP 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.
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A.(8.) SCHEDULE OF COMPLIANCE FOR TOTAL SILVER LIMITS (3-YEAR)
[NCGS 143-215.1 (b.)]
(a.) By May 1, 2025, the Permittee shall submit to the Division a Corrective Action Plan (CAP) for
Division approval, summarizing the strategy or actions to be taken to achieve compliance with the
Total Silver limitations listed in Section A. (1.). This plan will include specific dates for completion
or implementation of each action, which may include elimination of discharge.
(b.) By May 1, 2026, the Permittee shall submit to the Division a summary of actions taken towards
achieving compliance with the Total Silver limitations specified in Section A. (1.).
(c.) By May 1, 2027, the Permittee shall achieve compliance with Total Silver limitations specified in
Section A. (1.) or alternatively, the Facility may cease discharge.
(d.) Upon approval of the Corrective Action Plan (CAP) by the Division, the report, actions, and
implementation dates become an enforceable part of this permit. Any modifications to the schedule
shall be requested to the Division at least ninety (90) days before the deadline. Modifications to the
schedule more than four months will be subject to public notice.
(e.) Annual summaries and the CAP shall include the owner's name, NPDES permit number, and
a Permittee contact person and shall be submitted to:
NCDEQ / Division of Water Resources NCDEQ / Division of Water Resources
NPDES Permitting Fayetteville Regional Office
1617 Mail Service Center 610 East Center Avenue, Suite 301
Raleigh, NC 27699-1617 Mooresville, NC 28115
A.(9.) 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 21-1.0112 (b) (1) and 21-1.0114 (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.(10.) PFAS MONITORING REQUIREMENT
[NCGS 143-215.1(b.)]
(a.) In the absence of an approved 40 CFR Part 136 method published in Federal Register, influent and
effluent PFAS monitoring shall be conducted. The 3'd drain or more recent wastewater analytical
method 1633 (see 40 CFR 122.21(e)(3Xii) and 40 CFR 122.44(i)(1)(iv)(B)) shall be used and shall
include all target analytes listed under Table 1 of the method until such time as the Permittee uses
the approved PFAS Method for wastewater. Effective the first full calendar quarter following six (6)
months after EPA publishes a 40 CFR Part 136 PFAS Method for wastewater in the Federal Register,
influent and effluent PFAS monitoring shall be conducted using the approved EPA PFAS Method
1633. See Appendix A for list of analytes.
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(b.) Influent and effluent monitoring using the draft analytical method takes effect the first full
calendar quarter following six (6) months after the effective date of the permit (November 1,
2024) and will be at a quarterly frequency thereafter.
Appendix A has been added to the permit to identify the current analytes listed under Table 1 of
Method 1633 Analysis of Per- and Polyfluoroalkyl Substances (PFAS) in Aqueous, Solid, Biosolids,
and Tissue Samples by LC-MS/MS (EPA, January 2024) and the appropriate ICIS codes for use when
reporting in the electronic Discharge Monitoring Reports (eDMRs). The method and list of analytes
may also be found at:
https://www.epa.gov/system/files/documents/2024-01 /method-1633-final-for-web-postingpdf
HAS Monitoring using the January 2024 Method 1633 shall be reported quarterly using the Division -
provided submittal form. Once HAS monitoring is conducted using the HAS Method 1633 in 40
CFR Part 136, data shall be reported in the monthly eDMRs.
Please note that specific considerations and protocols are required to avoid cross -contamination and
minimize sample bias for PFAS. A current listing of laboratories accredited by the Perry Johnson
Laboratory Accreditation, Inc. (PJLA), ANSI National Accreditation Board (ANAB), or the
American Association for Laboratory Accreditation (A2LA) to perform EPA Method 1633 can be
found by contacting the individual associations. Please note that different labs are accredited for
different matrices.
Sampling and Analytical Notes:
• Sampling shall be planned so that required holding times for analytical methods are met.
• Using one of the analytical laboratories included above will allow consistency in analytical
method and in anticipation of a final method.
• "J" flag values shall be reported when the "J" flag value is associated with the method's upper
bound. "J" flag values need not be reported when less than the method's Minimum Reporting
Level (listed in Method 1633).
• Laboratories approved for Aqueous matrix may be utilized. Please note that the lab used does
not have to be in North Carolina.
(c.) Pretreatment program activities:
(i.) HAS Monitoring Applicability: Industry categories known or suspected to discharge PFAS
from the EPA HAS Strategic Roadmap include: organic chemicals, plastics & synthetic fibers
(OCPSF); metal finishing; electroplating; electric and electronic components; landfills; pulp,
paper & paperboard; leather tanning & finishing; plastics molding & forming; textile mills;
paint formulating, and airports. This is not an exhaustive list and additional industries may also
discharge PFAS. For example, Centralized Waste Treatment (CWT) facilities may receive
wastes from the aforementioned industries and should be considered for monitoring. There may
also be categories of dischargers that do not meet the applicability criteria of any existing
Effluent Limitation Guidelines (ELG); for instance, remediation sites, chemical manufacturing
not covered by OCPSF, and military bases.'
' ELG categories of airport deicing, landfills, textile mills, and plastics molding and forming do not
have categorical pretreatment standards, and therefore small -volume indirect dischargers in those
categories would not ordinarily be considered Significant Industrial Users (SIUs) and may not be
captured on an existing IU inventory. IUs under the Paint Formulating category are only subject to
Pretreatment Standards for New Sources (PSNS), and existing sources may need to be inventoried.
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(ii.) The Permittee shall identify and locate each Significant Industrial User (SIU) in the approved
pretreatment program in industry categories expected or suspected of PFAS discharges to the
Mount Holly WWTP; and begin sampling of and modify Industrial User Permits (IUPs) for
each SIU identified as suspected of PFAS discharges to the Mount Holly WWTP to ensure
sampling begins within six months of the permit effective date, by November 1, 2024.
(iii.) Update Industrial Waste Survey (IWS) Inventory: POTWs must identify and locate all possible
indirect dischargers that might be subject to the pretreatment program and identify the character
and volume of pollutants contributed to the POTW by the indirect dischargers (see 40 CFR
403.8(f)(2)). As EPA regulations require, this information shall be provided to the Division (see
40 CFR 122.440) and 40 CFR 403.8(f)(6)) as part of the 2024 Pretreatment Annual Report
(PAR). The IWS inventory shall be revised, as necessary, to include all indirect dischargers in
industry categories expected or suspected of PFAS discharges.'- (see 15A NCAC 02H
.0906(b)(2)).
(iv.) The Permittee shall begin sampling of and/or issue IUPs for each indirect discharger identified
as suspected of PFAS discharges to the Mount Holly WWTP to ensure sampling begins within
six months of completion of the IWS.
(v.) The Division has determined that all SIUs and indirect dischargers identified above analyze
their discharge for PFAS at the same quarterly sampling frequency and with the same
analytical method to ensure protection of human health and the environment due to the
potential health hazards associated with PFAS. Collection and evaluation of this information
will also assist the Department in developing sound policies with respect to PFAS in the
environment.
(vi.) The Permittee shall ensure that IUPs within the Mount Holly WWTP service area are modified
or reissued, new IUPs are issued, and other Pretreatment Program mechanisms are completed
to address PFAS discharges to POTWs.
(vii.) In the absence of local limits, and based upon data as they become available, POTWs shall
encourage Best Management Practices (BMPs), pollution prevention, product substitution, and
good housekeeping practices to make meaningful reductions in PFAS introduced to POTWs.
Such BMPs could be like those included in the EPA Office of Water, December 5, 2022,
"Addressing PFAS Discharges in NPDES Permits and Through the Pretreatment Program and
Monitoring Programs."A3. "Best Management Practices (BMPs) for discharges of PFAS,
including product substitution, reduction, or elimination of PFAS, as detected by draft method
1633".
(viii.) A summary of all actions taken by the Permittee and their industries and monitoring conducted
by each indirect discharger identified as part of this Special Condition shall be provided as part
of the PAR (see 15A NCAC 02H .0908(b)).
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A.(11.) ELECTRONIC REPORTING - 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 Reauirements [Supersedes Section D. (2.) and Section E. (5.) (a)l
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 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:
NC DEQ / 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.
Monitoring results obtained during the previous month(s) shall be summarized for each month and
reported via the eDMR system no later than the last calendar day of the month following the completed
reporting period. 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; and
• Pretreatment Program Annual Reports; and
• Clean Water Act (CWA) Section 316(b) Annual Reports.
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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 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)1
All eDMRs submitted to the permit issuing authority shall be signed by a person described in Part I1,
Section B. (I I .)(a) or by a duly authorized representative of that person as described in Part II, Section
B. (II.)(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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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.)l
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 122.411.
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A.(12.) FACILITY CLOSURE REQUIREMENTS [NCGS 143-215. 1 (b)]
The Permittee shall follow the notification steps as follows:
(a.) By July 30, 2024, the Permittee shall submit a plan for closure and transfer of flow from Mount Holly
to Charlote Water facilities. This plan shall include notification to the Division of all plans for Mount
Holly's pretreatment program responsibilities in the process of transfer to the Charlotte Water utilities
(i.e., ultimate location of wastewater treatment depending on how it is distributed within Charlotte
Water).
(b.) The Permittee shall notify the Division of any change in plans for the transition process.
(c.) The Permittee shall notify the Division at least 90 days prior to the closure of any wastewater treatment
system covered by this permit. This permit cannot be rescinded while any activities requiring this permit
continue at the permitted facility.
(d.) All plans and notifications shall be sent to:
NCDEQ / Division of Water Resources
NPDES Permitting
1617 Mail Service Center
Raleigh, NC 27699-1617
NCDEQ / Division of Water Resources
Fayetteville Regional Office
610 East Center Avenue, Suite 301
Mooresville, NC 28115
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Appendix A. PFAS Target Analytes EPA Method 1633
(EPA, January 2024)
Target Analyte Name
Abbreviation
CAS Number
Parameter
Code
Perfluoroalkyl carboxylic acids
Perfluorobutanoic acid
PFBA
375-22-4
51522
Perfluoropentanoic acid
PFPeA
2706-90-3
51623
Perfluorohexanoic acid
PFHxA
307-24-4
51624
Perfluoroheptanoic acid
PFHpA
375-85-9
51625
Perfluorooctanoic acid
PFOA
335-67-1
51521
Perfluorononanoic acid
PFNA
375-95-1
51626
Perfluorodecanoic acid
PFDA
335-76-2
51627
Perfluoroundecanoic acid
PFUnA
2058-94-8
51628
Perfluorododecanoic acid
PFDoA
307-55-1
51629
Perfluorotndecanoic acid
PFTrDA
72629-94-8
51630
Perfluorotetradecanoic acid
PFTeDA
376-06-7
51531
Perfluoroalkyl sulfonic acids
Perfluorobutanesulfonic acid
PFBS
375-73-5
52602
Perfluoropentanesulfonic acid
PFPeS
2706-91-4
52610
Perfluorohexanesulfonic acid
PFHxS
355-46-4
52605
Perfluoroheptanesulfonic acid
PFHpS
375-92-8
52604
Perfluorooctanesulfonic acid
PFOS
1763-23-1
52606
Perfluorononanesulfonic acid
PFNS
68259-12-1
52611
Perfluorodecanesulfonic acid
PFDS
335-77-3
52603
Perfluorododecanesulfonic acid
PFDoS
79780-39-5
52632
Fluorotelomer sulfonic acids
I H, I H,2H,2H-Perfluorohexane sulfonic acid
4:2FTS
757124-72-4
52607
I H, I H,2H,2H-Perfluorooctane sulfonic acid
6:2FTS
27619-97-2
52608
IH,1H,211,2H-Perfluorodecane sulfonic acid
8:2FTS
39108-34-4
52609
Perfluorooctane sulfonamides
Perfluorooctanesulfonamide
PFOSA
754-91-6
51525
N-methyl perfluorooctanesulfonamide
NMeFOSA
31506-32-8
52641
N-ethyl perfluorooctanesulfonamide
NEtFOSA
4151-50-2
52642
Table continues on next page.
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Table continued from Appendix A. PFAS Target Analytes EPA Method 1633 (EPA, January 2024).
Target Analyte Name
Abbreviation
FCAS Number
Parameter
Code
Perfluorooctane sulfonamidoacetic acids
N-methyl perfluorooctanesulfonamidoacetic acid
NMeFOSAA
2355-31-9
5164J
N-ethyl perfluorooctanesulfonamidoacetic acid
NEtFOSAA
2991-50-6
51643
Perfluorooctane sulfonamide ethanols
N-methyl perfluorooctanesulfonamidoethanol
NMeFOSE
24448-09-7
51642
N-ethyl perfluorooctanesulfonamidoethanol
NetFOSE
1691-99-2
51641
Per- and Polyfluorother carboxylic acids
Hexafluoropropylene oxide dimer acid
HFPO-DA
13252-13-6
52612
4,8-Dioxa-3H-perfluorononanoic acid
ADONA
919005-14-4
52636
Perfluoro-3-methoxypropanoicacid
PFMPA
377-73-1
PF002
Perlfuoro-4-methoxybutanoic acid
PFMBA
863090-89-5
PF006
Nonafluoro-3,6-dioxaheptanoic acid
NFDHA
151772-58-6
52626
Ether sulfonic acids
9-Chlorohexadecafluoro-3-oxanonane-1-sulfonic acid
9C1-PF3ONS
756426-58-1
PF003
11-Chloroeicosafluoro-3-oxaundecane-l-sulfonic acid
11C1-PF3OUdS
763051-92-9
PF004
Perfluoro(2-ethoxyethane)sulfonic acid
PFEESA
113507-82-7
52629
Fluorotelomer carboxylic acids
3-Perfluoropropyl propanoic acid
3:3FTCA
356-02-5
PF001
2H,2H,3H,3H-Perfluorooctanoic acid
5:3FTCA
914637-49-3
PF007
3-Perfluoroheptyl propanoic acid
7:3FTCA
812-70-4
PF005
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SCALE: 1:24.000
USGS Quad: Mt. Holly, NC
OutfidlFacility
Latitude: 35° 16' 54.8" N 350 16' 57.7" N
Longitude: 81° 0' 34.9" W 810 0'
40.3" W
Stream Class: WS-IV, CA
North
Facility Location
Basin: Catawba HUC: 03050101
Mount Holly WWTP NCO021156
Receiving Stream: Catawba River
Gaston County
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