NC0021121_Draft Permit_20200811

d STAT•F
ROY COOPERt * otti
Gover nor
MICHAEL S.REGAN ` ^*a •. `
Secretor) 4,IL 4 °.
S.DANIEL SMITH NORTH CAROUNA
Director Environmental Quality
August 11, 2020
Mr. Chris Marion,ORC
City of Mount Airy
PO Box 70
Mount Airy,North Carolina 27030
Subject: Draft NPDES Permit Renewal
Permit NC0021121
Mount Airy WWTP
Surry County
Grade IV Biological WPCS
SIC Code 4952
Dear Mr. Marion:
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:
• Regulatory citations have been added to the permit.
• Limitations for Ammonia-Nitrogen(NH3-N)have been reduced based on North Carolina's use
of EPA's Ammonia-Nitrogen criteria in developing toxicity-based NH3-N allocations
protective of North Carolina streams [See A. (1.)].
• Based on all submitted effluent data reported below detection, Oil and Grease monitoring has
been removed from the permit[See A. (1.)].
• Based on the reasonable potential analysis(RPA)showing reasonable potential to violate state
water quality standards, Total Copper and Total Zinc limits have been added to the permit and
the quarterly monitoring requirement has been changed to monthly monitoring [See A. (1.)].
• To provide an opportunity for the City to develop a plan to assess sources of Total Copper in
order to come in compliance with the limits in Section A.(1.),a 3-year schedule of compliance
with the option to conduct a Water Effect Ratio (WER) study has been added to the permit
[See Special Condition A. (4.) Schedule of Compliance for Total Copper Limitations].
• Based on the RPA showing no reasonable potential to violate state water quality standards,the
monitoring requirement for Total Silver and Chloride have been removed from the
permit[See A. (1.)].
• The US EPA approved the NC WQS revisions on April 6,2016 with some exceptions.The
NC Division of Water Resources NPDES Permitting Unit is required to implement new
dissolved metal standards in all NPDES permits public noticed after April 6, 2016.The new
standards for most metals include acute standards.Further,the freshwater standards for
several metals are expressed as the dissolved form of the metals,and seven metals have
hardness-dependent equations.As a result,the NPDES Permitting Unit will need site-specific
effluent hardness data and instream hardness data,upstream of the discharge, for each facility
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monitoring these metals in order to calculate permit limitations. Effluent hardness and
instream hardness sampling,upstream of the discharge, have been added to the permit at a
monitoring frequency of quarterly [See A. (1)].
• Some of the wording has changed in Special Condition A. (3.),Chronic Toxicity Permit Limit
to allow for electronic submittal of test results. Please review each paragraph carefully of the
combined special condition carefully.
• Special Condition A. (2.) has been modified to update the specific three years in which the
Effluent Pollutant Scan shall be performed: 2021, 2022, and 2023. In addition, some of the
wording has changed to allow for electronic submittal of effluent pollutant scans and second
species toxicity results. Please read each paragraph carefully.
• Parameter codes have been added to the Effluent Limitations and Monitoring Requirements,
and the Effluent Pollutant Scans special conditions [See A. (1.)].
• 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 A. (6.)].
• A notation was made concerning the Electronic Reporting Rule—Phase 2 Extension. EPA is
proposing to extend the Phase 2 deadline from December 21,2020,to December 21,2023.The
current compliance date will be extended if the implementation date is extended as a fmal
regulation change in the Federal Register.
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/2BZ4xxx 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 Surry 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(919) 707-3611 or by email at [e-mail].
Sincerely,
Ga-u ?ettmottter
Gary Perlmutter,Environmental Specialist II
NPDES Complex Permitting Unit
Hardcopy: NPDES Files
eCopy: US EPA Region 4
DWR/Winston-Salem Regional Office/Water Quality/Lon Snider
DWR/Operator Certification Program/Maureen Kinney
DWR/Ecosystems Branch/Mark Vander Borgh
DWR/Aquatic Toxicology Branch/Hanna Headrick
Page 2 of 2

Permit NC0021121
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WATER RESOURCES
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provision of North Carolina General Statute 143-215.1, other lawful standards -
Commission, and the Federal Water Pollution Control Act, as amended, the
City of Mount Airy
is hereby authorized to discharge wastewater from a facility located at the
Mount Airy Wastewater Treatment Plant
1750 Andy Griffith Parkway
Mount Airy
Surry County
to receiving waters designated as Ararat River in the Yadkin-Pee Dee 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 xx, 2020.
This permit and authorization to discharge shall expire at midnight on February 28, 2024.
Signed this day Month xx, 2020.
DRAFT
S. Daniel Smith, Director
Division of Water Resources
By Authority of the Environmental Management Commission

Permit NC0021121
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 Mount Airy is hereby authorized to:
1. Continue to operate a 7.0 MGD wastewater treatment facility that includes the following
components:
• Mechanical bar screening
• Grit chamber
• Primary clarifiers
• Trickling filters
• Activated sludge tank
• Secondary clarifiers
• Belt press
• Sludge thickener
• Chlorine contact tank
• Dechlorination
• Anaerobic digestor
• Continuous recording flow meter
The facility is located at 1750 Andy Griffith Parkway South, Mount Airy in Surry County.
2. Discharge from said treatment works via Outfall 001 at the location specified on the attached map
into the Ararat River, classified C waters in the Yadkin-Pee Dee River Basin.
Page 2 of 12

Permit NC0021121
PART I
A. (1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS - Outfall 001
[15A NCAC 02B .0400 et seq., 02B .0500 et seq.]
Grade IV Biological Water Pollution Control System [15A NCAC 08G .0302]
a. Beginning on the effective date and lasting until permit expiration, the Permittee is authorized to
discharge treated wastewater from the Wastewater Treatment Plant via Outfall 001. Such discharges
shall be limited and monitored' by the Permittee as specified below:
EFFLUENT CHARACTERISTICS LIMITS MONITORING REQUIREMENTS
Monthly Weekly Daily Measurement Sample Type Sample
Parameter Code Average Average Maximum Frequency Location z
Flow 50050 7.0 MGD Continuous RecordingInfluent or
Effluent
BOD,5-day,20°C 3 C0310 30.0 mg/L 45.0 mg/L Daily Composite Influent and
Effluent
Total Suspended Solids(TSS)3 C0530 30.0 mg/L 45.0 mg/L Daily Composite Influent and
Effluent
Ammonia(NH3-N)Summer 2.1 mg/L 6.3 mg/L Daily Composite Effluent
(Apr 1 -Oct 31)
C0610
Ammonia(NH3-N)Winter 6.3 mg/L 18.9 mg/L Daily Composite Effluent
(Nov 1 -Mar 31)
Dissolved Oxygen(DO) 00300 Daily Average>_5.0 mg/L Daily Grab Effluent
Fecal Coliform 31616 200/100 mL 400/100 mL Daily Grab Effluent
(geometric mean)
Total Residual Chlorine(TRC)4 50060 28.0 µg/L Daily Grab Effluent
pH 00400 Between 6.0 and 9.0 Standard Units Daily Grab Effluent
Temperature(°C) 00010 Monitor and Report(MR) Daily Grab Effluent
Conductivity(Nmhos/cm) 00094 Monitor and Report Daily Grab Effluent
Total Nitrogen C0600 Monitor and Report Monthly Composite Effluent
(NO2+NO3+TKN)(mg/L)
Total Phosphorus(mg/L) C0665 Monitor and Report Monthly Composite Effluent
Total Hardness(as CaCO3) 00900 Monitor and Report QuarterlyComposite Effluent
(mg/L)5 P P
Total Copper 6 01042 29.7 pg/L 35.9 pg/L Monthly Composite Effluent
Total Zinc 01077 447 pg/L Monthly Composite Effluent
Chronic Toxicity 7 TGP3B Quarterly Composite Effluent
Effluent Pollutant Scan NC01 Monitor and Report Footnote 8 Footnote 8 Effluent
Total Hardness(as CaCO3) 00900 Monitor and Report Quarterly Grab Upstream
(mg/L)9
Dissolved Oxygen(mg/L) 00300 Monitor and Report Variable 2 Grab Upstream,
Downstream
Temperature(°C) 00010 Monitor and Report Variable 2 Grab Upstream,
Downstream
Footnotes on next page.
Page 3 of 12

Permit NC0021121
Footnotes:
1. The Permittee shall submit discharge monitoring reports electronically using NCDWR's eDMR application system;
see Section A.(6.).
2. Upstream is located at NC Highway 52; downstream is located (1) approximately 1.0 mile below the discharge
before the confluence with Stewarts Creek and (2) approximately 6.0 miles below the discharge before the
confluence with Caddle Creek. Stream samples shall be collected weekly from October 1 through May 30, and
3/week from June 1 through September 30. Instream monitoring for DO and Temperature is provisionally
waived in light of the Permittee's participation in the Yadkin-Pee Dee River Basin Association. Instream
monitoring will be immediately reinstated and the Division shall be notified immediately should the Permittee
end its participation in the Association.
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 bya North Carolina certified laboratory (includingfield-certified even if
P ),
these values fall below 50 µg/L.
5. Effluent Total Hardness sampling shall be conducted in conjunction with testing for hardness-dependent metals
(cadmium,chromium,copper,lead,nickel silver,and zinc).
6. The Permittee shall follow the total copper compliance schedule detailed in Special Condition A. (4). Starting on
the effective date of this permit,the Permittee shall perform monthly effluent Monitoring and Reporting for total
copper.
7. Metals monitoring shall coincide with chronic toxicity monitoring.
8. Whole Effluent Toxicity shall be monitored using the Pass/Fail Chronic Toxicity test with Ceriodaphnia dubia at
42%effluent.Samples shall be collected in January,April,July, and October,see Section A. (3.).
9. The Permittee shall perform three Effluent Pollutant Scans during the term of this permit;see Section A.(2.).
10. The Permittee shall sample instream hardness, upstream of the facility's discharge. The sample shall be
representative of the hardness in the receiving stream. If the Permittee is a member of the Monitoring Coalition
Program, sampling for instream hardness may be waived as long as the Monitoring Coalition agrees to sample
hardness at the nearest upstream location, at a minimum frequency of quarterly, and the Permittee has obtained
approval from DWR - NPDES Permitting Unit that the upstream station being monitored by the Coalition is
representative of the receiving stream for this discharge. The Permittee is responsible for submitting instream
hardness test results with its permit renewal application package. If Coalition membership is cancelled or the
Coalition terminates instream hardness sampling at the approved station,the Permittee will immediately notify the
Division and resume sampling for instream hardness,upstream of its discharge.
b. There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 4 of 12

Permit NC0021121
A. (2.) EFFLUENT POLLUTANT SCAN [NCGS 143-215.1(b)]
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: 2021, 2022, and 2023. 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. Samples should be
collected with one quarterly toxicity test each year, and must 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 1,2-dichloroethane 32103 Bis(2-chloroethoxy)methane 34278
Chlorine(total residual,TRC) 50060 Trans-1,2-dichloroethylene 34546 Bis(2-chloroethyl)ether 34273
Dissolved oxygen 00300 1,1-dichloroethylene 34501 Bis(2-chloroisopropyl)ether 34283
Nitrate 00620 1,2-dichloropropane 34541 Bis(2-ethylhexyl)phthalate 39100
Nitrite 00615 1,3-dichloropropylene 77163 4-bromophenyl phenyl ether 34636
Kjeldahl nitrogen 00625 Ethylbenzene 34371 Butyl benzyl phthalate 34292
Oil and grease 00556 Methyl bromide 34413 2-chloronaphthalene 34581
Phosphorus C0665 Methyl chloride 34418 4-chlorophenyl phenyl ether 34641
Total dissolved solids 70295 Methylene chloride 34423 Chrysene 34320
Hardness 00900 1,1,2,2-tetrachloroethane 81549 Di-n-butyl phthalate 39110
Antimony 01097 Tetrachloroethylene 34475 Di-n-octyl phthalate 34596
Arsenic 01002 Toluene 34010 Dibenzo(a,h)anthracene 34556
Beryllium 01012 1,1,1-trichloroethane 34506 1,2-dichlorobenzene 34536
Cadmium 01027 1,1,2-trichloroethane 34511 1,3-dichlorobenzene 34566
Chromium 01034 Trichloroethylene 39180 1,4-dichlorobenzene 34571
Copper 01042 Vinyl chloride 39175 3,3-dichlorobenzidine 34631
Lead 01051 Acid-extractable compounds: Diethyl phthalate 34336
Mercury(Method 1631E) COMER P-chloro-rn-creso 34452 Dimethyl phthalate 34341
Nickel 01067 2-chlorophenol 34586 2,4-dinitrotoluene 34611
Selenium 01147 2,4-dichlorophenol 34601 2,6-dinitrotoluene C0626
Silver 01077 2,4-dimethylphenol 34606 1,2-diphenylhydrazine 34346
Thallium 01059 4,6-dinitro-o-cresol 34657 Fluoranthene C0376
Zinc 01092 2,4-dinitrophenol 34616 Fluorene 34381
Cyanide 00720 2-nitrophenol 34591 Hexachlorobenzene C0700
Total phenolic compounds 32730 4-nitrophenol 34646 Hexachlorobutadiene 39702
Volatile organic compounds: Pentachlorophenol 39032 Hexachlorocyclo-pentadiene 34386
Acrolein 34210 Phenol 34694 Hexachloroethane 34396
Acrylonitrile 34215 2,4,6-trichlorophenol 34621 Indeno(1,2,3-cd)pyrene 34403
Benzene 34030 Base-neutral compounds: Isophorone 34408
Bromofomi 32104 Acenaphthene 34205 Naphthalene 34696
Carbon tetrachloride 32102 Acenaphthylene 34200 Nitrobenzene 34447
Chlorobenzene 34301 Anthracene CO220 N-nitrosodi-n-propylamine 34428
Chlorodibromomethane 34306 Benzidine 39120 N-nitrosodimethylamine 34438
Chloroethane 85811 Benzo(a)anthracene 34526 N-nitrosodiphenylamine 34433
2-chloroethyl vinyl ether 34576 Benzo(a)pyrene 34247 Phenanthrene 34461
Chloroform 32106 3,4 benzofluoranthene 34230 Pyrene 34469
Dichlorobromomethane 32101 Benzo(ghi)perylene 34521 1,2,4-trichlorobenzene 34551 I
1,1-dichbroethane 34496 Benzo(k)fluoranthene 34242
Reporting. Test results shall be reported electronically via eDMR or on DWR Form—DMR-PPA-1 (or
on a form approved by the Director) by December 31st of each designated sampling year. The report
shall be submitted to the following address:
Page 5 of 12

Permit NC0021121
NC DEQ/DWR/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
Additional Toxicity Testing Requirements for Municipal Permit Renewal. Please note that
Municipal facilities that are subject to the Effluent Pollutant Scan requirements listed above are also
subject to additional toxicity testing requirements specified in Federal Regulation 40 CFR 122.21(j)(5).
The US EPA requires four (4) toxicity tests for a test organism other than the test species currently
required in this permit. The multiple species tests should be conducted either quarterly for a 12-month
period prior to submittal of the permit renewal application, or four tests performed at least annually in
the four and one half year period prior to the application. These tests shall be performed for acute or
chronic toxicity, whichever is specified in this permit. The multiple species toxicity test results shall be
filed with the Aquatic Toxicology Branch at 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: ATForms.ATBAncdenr.gov.
Contact the Division's Aquatic Toxicology Branch at 919-743-8401 for guidance on conducting the
additional toxicity tests and reporting requirements. Results should also be summarized in Part E
(Toxicity Testing Data) of EPA Municipal Application Form 2A, when submitting the permit renewal
application to the NPDES Permitting Unit.
Page 6 of 12

Permit NC0021121
A. (3.) CHRONIC TOXICITY PASS/FAIL MONITORING(QUARTERLY)
[15A NCAC 02B .0200 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 42%.
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
January,April,July,and October. 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 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.
Page 7 of 12

Permit NC0021121
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.
A. (4.) SCHEDULE OF COMPLIANCE FOR TOTAL COPPER LIMITATIONS
[NCGS 143-215.1 (b)]
This compliance schedule includes the option for pursuing a Water Effect Ratio (WER) study for
developing site-specific limitations and compliance with the Total Copper limit.
1. If the Permittee wishes to conduct a WER study to develop site-specific Total Copper limitations,
then within six (6) months of the effective date of the permit, the Permittee shall submit to the
Division of Water Resources a Water-Effect Ratio (WER) study plan for approval.
a. Within eighteen (18) months of the WER study plan approval by the Division, the
Permittee shall submit to the Division a report summarizing the results of the WER study.
b. If the WER study results in site-specific Total Copper limits, the Permittee shall submit
to the Division a permit modification request to include the WER-derived limits subject
to review and approval by the Division and the appropriate permit modification process.
c. The final total copper limits based on the WER-derived limits,if approved,will be placed
into effect immediately with the permit modification and all remaining schedule items
will be removed.
2. If the Permittee does not submit a WER study plan within six(6)months of the permit effective
date, then the Permittee shall follow the Compliance Schedule outlined below (replacing the
schedule in section A.4.1. above) and substitute the dates for one, two and three years from the
permit effective date:
a. Within one(1)year of the permit effective date,the Permittee shall submit to the Division
of Water Resources a Corrective Action Plan(CAP)for Division approval, summarizing
the strategy or actions to be taken to achieve compliance with the Total Copper limitations
listed in Section A. (1.). This plan will include specific dates for completion or
implementation of each action.
b. Within two(2)years of the effective date of the permit,the Permittee shall submit a report
to the Division summarizing actions taken in accordance with the Action Plan.
c. The Permittee shall achieve compliance with Total Copper limitations specified in
Section A. (1.)within three(3)years of the effective date of the permit.
Upon approval of the CAP by the Division, the report and actions become an enforceable part of this
permit. The Division can reopen this permit to implement interim or alternative limits based on studies
that demonstrate an interim or alternate limit is appropriate. Any modifications to the schedule shall be
requested to the Division at least ninety(90) days before the deadline. Modifications to the schedule in
excess of four months will be subject to public notice.
Page 8 of 12

Permit NC0021121
The WER Study Plan, CAP and all reports shall include the owner's name,NPDES permit number and
Permittee contact person, and shall be submitted to:
(1) NCDEQ/Division of Water Resources (2) NCDEQ/Division of Water Resources
NPDES Permitting Winston-Salem Regional Office
1617 Mail Service Center 450 West Hanes Mill Road
Raleigh,NC 27699-1617 Winston-Salem,NC 27105
A. (5.) 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 action to address the Waste Load Allocation.
Page 9 of 12

Permit NC0021 121
A. (6.) ELECTRONIC REPORTING-DISCHARGE MONITORING REPORTS
[G.S. 143-215.1(b)]
Federal regulations require electronic submittal of all discharge monitoring reports(DMRs)and program
reports. The final NPDES Electronic Reporting Rule was adopted and became effective on December
21,2015.
NOTE: This special condition supplements or supersedes the following sections within Part II of this
permit(Standard Conditions for NPDES Permits):
Section B. (11.) Signatory Requirements
Section D. (2.) Reporting
Section D. (6.) Records Retention
Section E. (5.) Monitoring Reports
1. Reporting Requirements [Supersedes Section D. (2.) and Section E. (5.) (a)►
The permittee shall report discharge monitoring data electronically using the NC DWR's Electronic
Discharge Monitoring Report(eDMR)internet application.
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. 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.
Regardless of the submission method, the first DMR is due on the last day of the month following
the issuance of the permit or in the case of a new facility,on the last day of the month following the
commencement of discharge.
Starting on December 21, 2020, the permittee must electronically report the following compliance
monitoring data and reports,when applicable:
• Sewer Overflow/Bypass Event Reports;
• Pretreatment Program Annual Reports; and
• Clean Water Act(CWA) Section 316(b)Annual Reports.
Page 10 of 12

Permit NC0021121
➢ NPDES Electronic Reporting Rule — Phase 2 Extension. EPA is proposing to
extend the Phase 2 deadline from December 21,2020 until at least December 21,
2023. The current compliance date will be extended if the implementation date is
extended as a final regulation change in the federal register.
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
II, Section B. (11.)(a) or by a duly authorized representative of that person as described in Part II,
Page 11 of 12

Permit NC0021121
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 3 years from the
date of the report. This period may be extended by request of the Director at any time [40 CFR
122.41].
A. (7.) NUTRIENT REOPENER FOR HIGH ROCK LAKE [NCGS 143-215.1(b)]
This permit may be reopened and modified to implement nutrient requirements in accordance with any
future TMDL,nutrient criteria and/or nutrient management strategy for High Rock Lake.
Page 12 of 12

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NC0021121 - Mount Airy WWTP Facility x
USGS Quad: B16NE Location ail
Latitude: 36°28'10"N Permitted Flow: 7.0 MGD [not to scale]
Longitude: 80°36'00"W
Stream Class: C Sub-Basin: 03-07-03 North SurryCounty
Receiving Stream: Ararat River