NC0021521_Draft Permit_20241112

ROY COOPER
Governor
MARY PE14NY KELLEY
Secretary
RICHARD E. ROGERS, JR.
Director
NORTH CAROLINA
Environmental Quality
November 12, 2024
Cliff Williams, Mayor (Transmitted Electronically)
Town of Aurora
PO Box 86
Aurora, NC 27806-0086
Subject: Draft NPDES Permit NCO021521
Aurora WWTP
Grade I Biological WPCS
Beaufort County
Mayor Williams:
Attached 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 a few changes in the draft attached here from the existing permit. These changes are
summarized below.
• Regulatory Citations - Language has been added where necessary in the permit to provide regulatory
citations for permit requirements.
• Electronic Reporting - Permit language has been modified to be consistent with the finalization of
federal requirements for electronic reporting.
• Language on the Supplement to Permit Cover Sheet has been updated.
• Special Condition for Mercury Monitoring [Section A. (4)] — Mercury monitoring was required once
during the permit cycle in the previous permit. This analysis was not submitted. This draft permit
maintains this requirement (once during the permit term — 2029) and has put the special condition
language associated with this requirement back in the permit. If this monitoring shows no detection,
then the Division will consider the monitoring requirement in the next renewal.
• Map Update — The permit map and descriptive information on the permit map have been updated.
• Permit Expiration — The date has been adjusted to allow for a full five year permit term.
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. The latest
version of the standard conditions is available at https://www.deq.nc.gov/n/npdes-standard-conditions-
boilerplate-110920112/download?attachment and can be viewed online or downloaded as a PDF file.
North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 1 1617 Mail Service Center I Raleigh, North Carolina 27699-1617
NORTH CARODNA
oepeNmeeeW 0- 919.707.9000

Cliff Williams
Aurora WWTP Draft Renewal
Page 2
Concurrent with this notification the Division is publishing a notice in a newspaper having general
circulation in the Beaufort County area soliciting public comments on this draft permit.
Please provide any written comments you may have to me 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 contact me by email at [e-mail]. At this time, contact by email is the most
effective method. If we need to set up a call to discuss any issues, we can set that up through email.
Sincerely,
l
Bradley Bennett
Compliance and Expedited Permitting Unit
cc: NPDES Files - electronic
Washington Regional Office / Water Quality — electronic
Operator Certification Program/Jeffrey Talbott — electronic
Aquatic Toxicology / Cindy Moore and Molly Nicholson — electronic

Draft Permit NCO021521
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WATER RESOURCES
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
N( PDES)
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
Town of Aurora
are hereby authorized to discharge wastewater from a facility located at the
Aurora WWTP
Idalia Road
Aurora
Beaufort County
to receiving waters designated as South Creek [stream index 29-28-(4)] in subbasin 03-03-07 of the Tar -
Pamlico 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
This permit and authorization to discharge shall expire at midnight on February 28, 2030.
If the permittee intends to continue discharging at the facility beyond the term of this permit, a renewal
application must be submitted no later than September 1, 2029 (180 days before the expiration of this permit)
Signed this day
John Hennessy, Regional Operations Section Chief
Division of Water Resources
By Authority of the Environmental Management Commission
Page 1 of 9

Draft Permit NC0021521
SUPPLEMENT TO PERMIT COVER SHEET
Allprevious NPDES Permits issued to this facility, whetherfor 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 Town of Aurora is hereby authorized to:
Continue to operate an existing 0.12 MGD wastewater treatment system that includes the following
components:
➢ 4-acre lagoon system
➢ 1-acre pond
➢ 1.28 acre surface -flow constructed wetland consisting of 2 parallel cells
➢ Gas chlorination system [with liquid supplementation]
➢ Caustic drip system for pH control
➢ Dechlorination contact chamber
➢ Flow measuring device
➢ Effluent lift station
This facility is located at the Aurora WWTP (Idalia Road, Aurora) in Beaufort County.
2. Discharge from said treatment works at the location specified on the attached map into South Creek
[stream index 29-28-(4)], a waterbody currently classified SC -NSW waters in subbasin 03-03-07
[HUC: 030201040205] of the Tar -Pamlico River Basin.
Page 2 of 9

Draft Permit NCO021521
PART I
A. (1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
[15A NCAC 02B .0400 et seq., 02B .0500 et seq.]
Grade I Biological Water Pollution Control System [15A NCAC 08G.0302]
During the period beginning on the effective date of this permit and lasting until expiration, the
Permittee is authorized to discharge from outfall 001. Such discharges shall be limited and monitored' by
the Permittee as specified below:
PARAMETER
eDMR Code
LIMITS
MONITORING REQUIREMENTS
Monthly
Average
Weekly
Average
Daily
Maximum
Measurement
Frequency
Sample
Type
Sample
Location
Flow
50050
0.12 MGD
Continuous
RecordingInfluent
or
Effluent
BOD, 5-day (20°C) 2
C0310
30.0 mg/L
45.0 mg/L
2/Month
Composite
Influent &
Effluent
Total Suspended Solids2
C0530
90.0 mg/L
135.0 mg/L
2/Month
Composite
Influent &
Effluent
NH3 as N m /L
C0610
Monitor & Report
2/Month
Composite
Effluent
Dissolved Oxygen2
00300
Daily average > 5.0 mg/L
Weekly
Grab
Effluent
Enterococci (geometric
mean
61211
35/100 mL
276/100 mL
Weekly
Grab
Effluent
Total Residual Chlorine3
50060
13 /L
Daily
Grab
Effluent
Temperature °C
00010
Monitor & Report
Weekly
Grab
Effluent
Total Nitro en4 m /L
C0600
Monitor & Report
2/Month
Calculated
Effluent
TKN (mg/L)
00625
Monitor & Report
2/Month
Composite
Effluent
NO3-N+NO2-N m /L
00630
Monitor & Report
2/Month
Composite
Effluent
Total Phosphorus m /L
C0665
Monitor & Report
2/Month
Composite
Effluent
pH
00400
> 6.8 and < 8.5 standard units
2/Month
Grab
Effluent
Total Mercur e n /L
COMER
Monitor & Report
1/Permit4
Grab
Effluent
Acute Toxicit 6
TGE3E
Monitor & Report
Quarterly
Composite
Effluent
Footnotes:
1. The permittee shall submit discharge monitoring reports electronically using the Division's eDMR system [See A. (5)].
2. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed 35% of the respective
influent value (65% removal).
3. 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. TRC limit and monitoring requirements apply only if
chlorine is added to disinfect.
4. 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.
5. The permittee shall collect one sample of total mercury in calendar year 2029. Sampling and analysis will be performed
as specified in EPA Method 1631 E. [see A. (4)]
6. Acute Toxicity (Mysid shrimp 24-hour) Pass/Fail, no significant mortality at 90% with testing in March, June,
September and December [see A. (3)].
THERE SHALL BE NO DISCHARGE OF FLOATING SOLIDS OR VISIBLE FOAM IN OTHER THAN TRACE AMOUNTS.
Page 3 of 9

Draft Permit NCO021521
A. (2) NUTRIENT REDUCTION REQUIREMENT
[NCGS 143-215.1 (b)]
Dischargers to the Tar -Pamlico River are subject to the requirements, terms and conditions, of the Tar -
Pamlico Nutrient Sensitive Waters Implementation Strategy: Phase III adopted April 14, 2005. Non-
members of the Tar -Pamlico Association (Association) will maintain or receive permit effluent limits
for Total Nitrogen and for Total Phosphorus concentrations as defined in the Strategy. Any revisions to
the Strategy during the life of this permit are applicable.
If requirements other than those listed in this permit are adopted as part of a revision of the Strategy, the
Division reserves the right to reopen this permit to include these requirements.
A. (3) ACUTE TOXICITY PASS/FAIL MONITORING (QUARTERLY)
[15A NCAC 0213.0200 et seq.] [15A NCAC 02B .0500 et seq]
The permittee shall conduct acute toxicity tests on a quarterly basis using protocols defined in the North
Carolina Procedure Document entitled "Pass/Fail Methodology for Determining Acute Toxicity In A
Single Effluent Concentration" (Revised -December 2010, or subsequent versions). The monitoring shall
be performed as a Mysid Shrimp (Mysidopsis bahia) 24-hour static test. The effluent concentration at
which there may be at no time significant acute mortality is 90% (defined as treatment two in the
procedure document). The tests will be performed during the months of 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.
All toxicity testing results required as part of this permit condition will be entered electronically using
the Division's eDMR system for the month in which it was performed, using the parameter code
TGE3E. Additionally, DWR Form AT-2 (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, ATForms.ATBkdeq.nc. og_v.
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.
Page 4 of 9

Draft Permit NCO021521
Should there be no discharge of flow from the facility during a month in which toxicity monitoring is
required, the permittee will complete the information located at the top of the aquatic toxicity (AT) test
form indicating the facility name, permit number, pipe number, county, and the month/year of the report
with the notation of "No Flow" in the comment area of the form. The report shall be submitted to the
Water Sciences Section at the address cited above.
Should the permittee fail to monitor during a month in which toxicity monitoring is required, then
monthly monitoring will begin immediately. Upon submission of a valid test, this monthly test
requirement will revert to quarterly in the months specified above.
Should any test data from either these monitoring requirements or tests performed by the North Carolina
Division of Water Resources indicate potential impacts to the receiving stream, this permit may be re-
opened and modified to include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum control
organism survival and appropriate environmental controls, shall constitute an invalid test and will
require immediate follow-up testing to be completed no later than the last day of the month following
the month of the initial monitoring.
A. (4) EFFLUENT MERCURY ANALYSIS FOR PERMIT RENEWAL
[NCGS 143-215.1(b)]
(a.) The Permittee shall provide one effluent mercury analysis, using EPA Method 1631E, in
conjunction with the next permit renewal application. The analysis shall be taken within 12 months
prior to the renewal application due date. This mercury analysis and any additional effluent
mercury measurements conducted from the effective date of this permit and up to the application
date shall be submitted in an appropriate timeframe through eDMR and submitted with the renewal
application.
(b.) If the result of the mercury analysis is not provided with the application, the application may be
returned as incomplete, and the Permittee considered non -compliant.
A. (5) 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.)
• Section D. (2.)
• Section D. (6.)
• Section E. (5.)
Signatory Requirements
Reporting
Records Retention
Monitoring Reports
1. Reporting Requirements [Supersedes Section D. (2.) and Section E. (5.) (a)]
Page 5 of 9

Draft Permit NC0021521
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: hM2s://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;
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
Page 6 of 9

Draft Permit NC0021521
appropriate electronic reporting tool will be available as well. Information on EPA's NPDES
Electronic Reporting Rule is found at: htips://www.federalre ig ster.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:
hLtp://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. (I 1.)(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:
hqp:Hdeq.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:
7 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
Page 7 of 9

Draft Permit NCO021521
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.)]
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].
Page 8 of 9

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Town of Aurora
Facility
Aurora WWTP
Location
Receiving Stream:
South Creek Stream Class:
SC -NSW
River Basin:
Tar -Pamlico Sub -Basin:
03-03-07
(not to scale)
Outfall Latitude:
35' 17' 42" Outfall Longitude:
76' 46' 35"
Stream Segment
29-28-(4) HUCM
F31SE/Aurora County:
030201040205
Beaufort
NORTH
NPDES Permit NC0021521
Grid uad: