NC0020443_Fact Sheet_20230313

DEQ/DWR/NPDES
EXPEDITED FACT SHEET - NPDES PERMIT RENEWAL
NPDES Permit NCO020443
Joe R. Corporon, P.G., Compliance&Expedited Permitting Unit 13Mar203
Facility Information
Applicant/Facility Name Town of Columbia
Columbia Wastewater Treatment Plant (WWTP)
Applicant Address P.O. Box 361, Columbia,NC 27925
Facility Address 604 N. Road Street Extension(NCSR 1219)
Facility Contact Rhett White,Town Manager[[e-mail].]
Permitted Flow(MGD) 0.600 MGD
Type of Waste 100%Domestic Wastewater Discharge
Facility Class WPCS WW-2 County Tyrrell
Permit Status Renewal Regional Office WaRO
Stream Characteristics
Receiving Stream Scuppernong River Stream Classification SC
Stream Segment [30-14-4-9] Drainage basin Pasquotank
Summer 7Q10(cfs) Tidal Subbasin 03-01-53
Winter 7Q10(cfs) Tidal Use Support ND
30Q2 (cfs) Tidal 303(d)Listed No
Average Flow(cfs) Tidal State Grid D33NE
IWC(%) 100% USGS Topo Quad Columbia West,NC
Facility History-- Town of Columbia WWTP (Columbia) is a minor municipal (flow< 1 MGD)
WWTP, WPCS Grade 2 treating 100% domestic waste with a design capacity of 0.600 MGD. The
Permittee has made no significant changes in the system since last renewal. An upgrade in 2010
modified flow from 0.300 MGD to 0.600 MGD [ATC No. 020443A01]; see below, Treatment
System Configuration.
Compliance—The attached Violations Summary is sorted by year (newest to oldest). The latest
violations occurred in Dec2021. Occasional NOVs issued for enterococci and TSS (2021), and
TSS, BOD-5 (2020). Whole Effluent Toxicity(WET)testing is currently not required—no
changes recommended.
The Permittee Requests Changes for Renewal -- The Permittee's application requests DWR to
reduce monitoring frequencies (3/Week) for BOD-5, TSS, Ammonia Nitrogen (NH3 as N), and
Enterococci (see App.,Analysis of Testing Results for the Past Three Years. However, BIMS
databases suggest limit violations for these parameters (see attached Compliance Summary).
DWR suggested to the Permittee that implementing an effluent diffuser may afford dilution but has
received no additional input from the Permittee. Therefore, no renewal changes recommended.
For Renewal—Updated facility description and map; updated table and footnotes [section A. (1.)];
updated text for Electronic Reporting.
Receiving-Stream—Columbia discharges via Outfall 001 into the Scuppernong River [Stream
Segment 30-14-4-9], Classified SC waters. This segment is not listed as impaired in the 2018
North Carolina 303(d)report.
Fact Sheet-Renewal Mar2023
NPDES Permit NCO020443
Page 1 of 7

Implementation of 2012 Statewide Mercury TMDL—Initially, Columbia's permit required
Quarterly monitor for Mercury in keeping with a statewide Mercury strategy. In response to the
Columbia's request (05Jan2015), the Division reduced monitoring from Quarterly to Annually
(03Mar2015), and in 2017, again modified monitoring to once (1)per permit cycle [see A. (L),
footnote 7]. No changes recommended for this renewal.
Treatment System Confi urg ation:
♦ influent flow meter
♦ a mechanical bar screen with manual bar screen bypass
♦ aerated grit removal system
♦ two (2) each 325,000-gallon oxidation ditches [w/return-activated sludge]
♦ four(4) each 65,000 gallon, 30-ft diameter clarifiers
♦ one RAS tank [10,000-gal w/centrifuge return]
♦ one 200,000-gallon aerated sludge holding tank
♦ one 154,000-gallon aerated sludge holding tank
♦ one 52,000-gallon sludge digester
♦ effluent treatment pump station with chlor/dechlor, dosing and chemical contact
o two (2) each 2.5-gpm pumps [chemical-feed, diaphragm]
0 one 12,000-gal wastewater holding tank [disinfection
[NaCIO] chlorine-contact]
o two (2) each 11,500-gal post-aeration basins
0 one 10,000-gal dechlor tank for dechlor mixing [Ca03S2]
♦ outfall pump station with two (2) each 20-hp effluent pumps [vertical turbine]
♦ effluent flow meter
♦ 34-ft receiving-stream effluent diffuser
♦ standby generator
Flow Summary—Jan2013-Jul2017
Year Average n Minimum Maximum
2017 0.261 365 0.142 671
2018 0.298 365 0.095 0.902
2019 0.226 365 0.049 0.838
2020 0.190 365 0.063 0.679
2021 0.187 365 0.055 0.742
2022 0.179 1 120 0.095 0.417
RPA—A Reasonable Potential Analysis(RPA)was not applied for this renewal, deemed unwarranted
considering this permit's parameters of concern.
Page 2 of 7

PROPOSED SCHEDULE OF ISSUANCE
Draft Permit to Public Notice: 12M2022
Permit Scheduled to Issue: 24Mar2023 (est.)
Effective Date O1May2023 (est.)
NPDES DIVISION CONTACT
If you have questions about any of the above information, or on the attached permit, please email
Joe R. Corporon, P.G. [e-mail]].
NAME: DATE: 13MAR2023
J
NPDES Implementation of Instream Dissolved Metals Standards — Freshwater
Standards
The NC 2007-2015 Water Quality Standard(WQS)Triennial Review was approved by the NC
Environmental Management Commission(EMC) on November 13,2014. The US EPA subsequently
approved the WQS revisions on April 6, 2016,with some exceptions. Therefore,metal limits in draft
permits out to public notice after April 6,2016 must be calculated to protect the new standards -as
approved.
Table 2.NC Dissolved Metals Water ualit Standards/A uatic Life Protection
Parameter Acute FW, µg/l Chronic FW, µg/1 Acute SW, µg/1 Chronic SW, µg/1
(Dissolved) (Dissolved) (Dissolved) (Dissolved)
Arsenic 340 150 69 36
Beryllium 65 6.5 --- ---
Cadmium Calculation Calculation 40 8.8
Chromium III Calculation Calculation --- ---
Chromium VI 16 11 1100 50
Copper Calculation Calculation 4.8 3.1
Lead Calculation Calculation 210 8.1
Nickel Calculation Calculation 74 8.2
Silver Calculation 0.06 1.9 0.1
Zinc Calculation Calculation 90 81
Page 3 of 7

Table 2 Notes:
1. FW=Freshwater, SW= Saltwater
2. Calculation=Hardness dependent standard
3. Only the aquatic life standards listed above are expressed in dissolved form. Aquatic life standards
for Mercury and selenium are still expressed as Total Recoverable Metals due to bioaccumulative
concerns(as are all human health standards for all metals). It is still necessary to evaluate total
recoverable aquatic life and human health standards listed in 15A NCAC 2B.0200(e.g.,arsenic at
10 µg/l for human health protection; cyanide at 5 µg/L and fluoride at 1.8 mg/L for aquatic life
protection).
Table 3.Dissolved Freshwater Standards for Hardness-Dependent Metals
The Water Effects Ratio(WER) is equal to one unless determined otherwise under 15A NCAC
02B .0211 Subparagraph(11)(d)
Metal NC Dissolved Standard, 1
Cadmium,Acute WER*{1.136672-[In hardness](0.041838){ e^{0.9151 [ln hardness]-
3.1485}
Cadmium, Acute Trout WER*{1.136672-[ln hardness](0.041838){ e^{0.9151[ln hardness]-
waters 3.62361
Cadmium,Chronic WER*{1.101672-[ln hardness](0.041838){ e^{0.7998[ln hardness]-
4.4451}
Chromium III,Acute WER*0.316 e^{0.8190[ln hardness]+3.7256{
Chromium III,Chronic WER*0.860 e^{0.8190[ln hardness]+0.6848)
Copper, Acute WER*0.960 e^{0.9422[1n hardness]-1.700{
Copper, Chronic WER*0.960 e"{0.8545[ln hardness]-1.702{
Lead,Acute WER*{1.46203-[ln hardness](0.145712){ e^{1.273[ln hardness]-
1.460)
Lead, Chronic WER*{1.46203-[In hardness](0.145712)} e^{1.273[ln hardness]-
4.705}
Nickel,Acute WER*0.998 e^{0.8460[ln hardness]+2.255{
Nickel,Chronic WER*0.997 e^{0.8460[ln hardness]+0.0584{
Silver,Acute WER*0.85 • e^{1.72[ln hardness]-6.59{
Silver, Chronic Not applicable
Zinc,Acute WER*0.978 e^{0.8473[ln hardness]+0.884}
Zinc, Chronic WER*0.986 e^{0.8473[ln hardness]+0.884}
General Information on the Reasonable Potential Analysis (RPA)
The RPA process itself did not change as the result of the new metals standards. However, application of
the dissolved and hardness-dependent standards requires additional consideration in order to establish the
numeric standard for each metal of concern of each individual discharge.
The hardness-based standards require some knowledge of the effluent and instream(upstream)hardness and
so must be calculated case-by-case for each discharge.
Page 4 of 7

Metals limits must be expressed as `total recoverable' metals in accordance with 40 CFR 122.45(c). The
discharge-specific standards must be converted to the equivalent total values for use in the RPA
calculations. We will generally rely on default translator values developed for each metal(more on that
below),but it is also possible to consider case-specific translators developed in accordance with established
methodology.
RPA Permitting Guidance/WQBELs for Hardness-Dependent Metals-Freshwater
The RPA is designed to predict the maximum likely effluent concentrations for each metal of concern,
based on recent effluent data, and calculate the allowable effluent concentrations,based on applicable
standards and the critical low-flow values for the receiving stream.
If the maximum predicted value is greater than the maximum allowed value (chronic or acute),the
discharge has reasonable potential to exceed the standard,which warrants a permit limit in most cases. If
monitoring for a particular pollutant indicates that the pollutant is not present(i.e. consistently below
detection level),then the Division may remove the monitoring requirement in the reissued permit.
1. To perform a RPA on the Freshwater hardness-dependent metals the Permit Writer compiles the
following information:
• Critical low flow of the receiving stream, 7Q 10(the spreadsheet automatically calculates
the 1 Q 10 using the formula 1 Q 10=0.843 (s7Q 10, cfs)0.993
• Effluent hardness and upstream hardness, site-specific data is preferred
• Permitted flow
• Receiving stream classification
2. In order to establish the numeric standard for each hardness-dependent metal of concern and for
each individual discharge,the Permit Writer must first determine what effluent and instream
(upstream)hardness values to use in the equations.
The permit writer reviews DMR's, Effluent Pollutant Scans,and Toxicity Test results for any
hardness data and contacts the Permittee to see if any additional data is available for instream
hardness values,upstream of the discharge.
If no hardness data is available,the permit writer may choose to do an initial evaluation using a
default hardness of 25 mg/L(CaCO3 or(Ca+Mg)). Minimum and maximum limits on the
hardness value used for water quality calculations are 25 mg/L and 400 mg/L,respectively.
If the use of a default hardness value results in a hardness-dependent metal showing reasonable
potential,the permit writer contacts the Permittee and requests 5 site-specific effluent and upstream
hardness samples over a period of one week. The RPA is rerun using the new data.
The overall hardness value used in the water quality calculations is calculated as follows:
Combined Hardness(chronic)
_(Permitted Flow, cfs *Avg. Effluent Hardness,mg/L)x(s7Q 10, cfs *Avg. Upstream Hardness,mg/L)
(Permitted Flow, cfs+s7Q 10,cfs)
The Combined Hardness for acute is the same but the calculation uses the IQ 10 flow.
3. The permit writer converts the numeric standard for each metal of concern to a total recoverable
metal,using the EPA Default Partition Coefficients(DPCs) or site-specific translators,if any have
been developed using federally approved methodology.
Page 5 of 7

EPA default partition coefficients or the"Fraction Dissolved"converts the value for
dissolved metal at laboratory conditions to total recoverable metal at in-stream ambient
conditions.This factor is calculated using the linear partition coefficients found in The
Metals Translator: Guidance for Calculating a Total Recoverable Permit Limit from a
Dissolved Criterion(EPA 823-B-96-007,June 1996)and the equation:
Cdiss = 1
Ct.tal 1 + { [Kr.] [SS(i+a)] [10-6] }
Where:
ss=in-stream suspended solids concentration[mg/1],minimum of 10 mg/L used,and
Kpo and a=constants that express the equilibrium relationship between dissolved and
adsorbed forms of metals.A list of constants used for each hardness-dependent metal can
also be found in the RPA program under a sheet labeled DPCs.
4. The numeric standard for each metal of concern is divided by the default partition coefficient(or
site-specific translator)to obtain a Total Recoverable Metal at ambient conditions.
In some cases,where an EPA default partition coefficient translator does not exist(ie. silver),the
dissolved numeric standard for each metal of concern is divided by the EPA conversion factor to
obtain a Total Recoverable Metal at ambient conditions. This method presumes that the metal is
dissolved to the same extent as it was during EPA's criteria development for metals. For more
information on conversion factors see the June, 1996 EPA Translator Guidance Document.
5. The RPA spreadsheet uses a mass balance equation to determine the total allowable concentration
(permit limits) for each pollutant using the following equation:
Ca=(s7Q 10+Qw) (Cwgs)-(s7Q 10) (Cb)
Qw
Where: Ca=allowable effluent concentration(µg/L or mg/L)
Cwqs=NC Water Quality Standard or federal criteria(µg/L or mg/L)
Cb=background concentration: assume zero for all toxicants except NH3* (µg/L or mg/L)
Qw=permitted effluent flow(cfs,match s7Q 10)
s7Q 10=summer low flow used to protect aquatic life from chronic toxicity and human health
through the consumption of water, fish, and shellfish from noncarcinogens(cfs)
* Discussions are on-going with EPA on how best to address background concentrations
Flows other than s7Q 10 may be incorporated as applicable:
IQ 10=used in the equation to protect aquatic life from acute toxicity
QA=used in the equation to protect human health through the consumption of water, fish,
and shellfish from carcinogens
30Q2=used in the equation to protect aesthetic quality
Page 6 of 7

6. The permit writer enters the most recent 2-3 years of effluent data for each pollutant of concern.
Data entered must have been taken within four and one-half years prior to the date of the permit
application(40 CFR 122.21). The RPA spreadsheet estimates the 95th percentile upper
concentration of each pollutant. The Predicted Max concentrations are compared to the Total
allowable concentrations to determine if a permit limit is necessary. If the predicted max exceeds
the acute or chronic Total allowable concentrations,the discharge is considered to show reasonable
potential to violate the water quality standard, and a permit limit(Total allowable concentration)is
included in the permit in accordance with the U.S. EPA Technical Support Document for Water
Quality-Based Toxics Control published in 1991.
7. When appropriate,permit writers develop facility specific compliance schedules in accordance with
the EPA Headquarters Memo dated May 10,2007 from James Hanlon to Alexis Strauss on 40 CFR
122.47 Compliance Schedule Requirements.
8. The Total Chromium NC WQS was removed and replaced with trivalent chromium and hexavalent
chromium Water Quality Standards. As a cost savings measure,total chromium data results may be
used as a conservative surrogate in cases where there are no analytical results based on chromium
III or VI. In these cases,the projected maximum concentration(95th%)for total chromium will be
compared against water quality standards for chromium III and chromium VI.
9. Effluent hardness sampling and instream hardness sampling,upstream of the discharge,are inserted
into all permits with facilities monitoring for hardness-dependent metals to ensure the accuracy of
the permit limits and to build a more robust hardness dataset.
10. Hardness and flow values used in the Reasonable Potential Analysis for this permit included:
Table 4
Parameter Value Comments Data Source
Average Effluent Hardness (mg/L) N/A No metals monitored
[Total as, CaCO3 or(Ca+Mg)]
Average Upstream Hardness(mg/L) N/A
[Total as, CaCO3 or(Ca+Mg)]
7Q 10 summer(cfs) 0.0 Tidal
1 Q 10 (cfs) 0.0 Tidal
Permitted Flow(MGD) N/A 0.600
Page 7 of 7

Permit NCO020443
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WATER RESOURCES
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
(NE DES)
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 Columbia
is hereby authorized to discharge wastewater from a facility located at the
Columbia WWTP
604 N. Road Street Extension (NCSR 1209)
Tyrrell County
to receiving waters designated as the Scuppernong River in the Pasquotank 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 December 1, 2017.
This permit and authorization to discharge shall expire at midnight on December 31, 2022.
Signed this day October 18, 2017.
S. Jay Zimmerman, P.G., Director
Division of Water Resources
By Authority of the Environmental Management Commission
Page 1 of 6

Permit NCO020443
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility, whether for operation or discharge are hereby
revoked, and as of this issuance, any previously issued permit bearing this number is no longer effective.
Therefore, the exclusive authority to operate and discharge from this facility arises under the permit
conditions, requirements, terms, and provisions described herein.
Town of Columbia
is hereby authorized to:
1. continue to operate an existing 0.600 MGD wastewater treatment plant including the
components;
♦ influent flow meter
♦ a mechanical bar screen with manual bar screen bypass
♦ aerated grit removal system
♦ two (2) each 375,000-gallon oxidation ditches [w/return-activated sludge]
♦ four(4) each 65,000 gallon, 30-ft diameter clarifiers
♦ one RAS tank [10,000-gal w/centrifuge return]
♦ one 200,000-gallon aerated sludge holding tank
♦ one 154,000-gallon aerated sludge holding tank
♦ one 52,000-gallon sludge digester
♦ effluent pump station with chlor/dechlor, dosing and chemical contact
o two (2) each 2.5-gph pumps [chemical-feed, diaphragm]
0 one 12,000-gal wastewater holding tank [disinfection [NaC10] chlorine-contact]
o two (2) each 11,500-gal post-aeration basins
0 one 10,000-gal dechlor tank for dechlor mixing [Ca03S2]
♦ outfall pump station with two (2) each 20-hp effluent pumps [vertical turbine]
♦ effluent flow meter
♦ a 34-ft instream effluent diffuser assembly
♦ standby generator
these facilities located at the Columbia WWTP, 604 N. Road Street Extension (NCSR 1209)near
Columbia in Tyrrell County; and
2. discharge from said treatment works via Outfall 001, at a location specified on the attached map,
into the Scuppernong River [Stream Index 30-14-4-(9)], a waterbody currently classified SC
within Subbasin 03-01-53 [ffUC: 03010205] of the Pasquotank River Basin.
Page 2 of 6

Permit NCO020443
PART I
A. (L) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
[15A NCAC 02B .0400 et seq., 02B .0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee
is authorized to discharge 0.600 MGD of treated wastewater from Outfall 001. Such discharges shall be
limited, monitored and reported 1 by the Permittee as specified below:
EFFLUENT CHARACTERISTIC LIMITS MONITORING REQUIREMENTS
[Parameter Codes] Monthly Weekly Daily Measurement Sample Sample
Average Average Maximum Frequency Type Location 2
Flow(MGD) 50050 0.600 MGD Continuous Recording I or E
Temperature(°C) 00010 Monitor&Report Daily Grab E
Total Residual Chlorine 3 50060 13 µg/L 3/Week Grab E
BOD 5-day,20°C 4 00310 7.0 mg/L 10.5 mg/L 3/Week Composite I,E
Total Suspended Solids 4 00530 30.0 mg/L 45.0 mg/L 3/Week Composite I,E
NH3 as N C0610 2.0 mg/L 6.0 mg/L 3/Week Composite E
Enterococci 5 61211 35/100 mL 276/100 mL 3/Week Grab E
Dissolved Oxygen(DO) 00300 Daily average>6.0 mg/L 3/Week Grab E
pH 00400 >6.8 and<8.5 standard units 3/Week Grab E
Total Phosphorus(mg/L) C0665 Monitor&Report Quarterly Composite E
TKN (mg/L)6 00625 Monitor&Report Quarterly Composite E
NO3-N+NO2-N (mg/L)6 00630 Monitor&Report Quarterly Composite E
TN (mg/L)6 C0600 Monitor&Report Quarterly Calculated E
Mercury 7 COMER Monitor&Report Once per Grab E
permit cycle
Notes:
1. The Permittee shall submit monthly Discharge Monitoring Reports(DMRs)electronically using DWR's
Electronic Discharge Monitoring Report[eDMR]Program,as detailed herein[see Section A. (2)].
2. I=Influent;E=Effluent
3. Total Residual Chlorine(TRC).The Division shall consider compliant all effluent TRC values reported
below 50 µg/L.However,the Permittee shall continue to record and submit all values reported by North
Carolina-certified test methods(including field certified),even if these values fall below 50 µg/L.
4. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed 15%of
the respective influent value(i.e., 85%removal required).
5. Enterococci shall be calculated using the geometric mean in accord with procedure detailed in Part II.,
Section A.
6. 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.
7. Low-level mercury sampling and analysis protocols are required using EPA Method 1631E.
Conditions: Sample effluent downstream of all treatment,prior to mixing with receiving waters.
Discharge shall contain no floating solids or foam visible in other than trace amounts.
Page 3 of 6

Permit NCO020443
A. (2.) NUTRIENT REOPENER
[G.S. 143-215.3(a)(2) or[G.S. 143-215.66]
The Division may modify, or revoke and reissue this permit to include revised effluent
limitations for nutrients, depending:
➢ on findings of a study by the Division to determine if nutrient control is necessary;
➢ if local actions do not successfully reduce nutrient loading to the receiving waters;
➢ on the onset of problem conditions in the receiving waters.
A. (3.) ELECTRONIC REPORTING OF 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)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 electronically using eDMR. The eDMR system allows permitted facilities to enter
monitoring data and submit DMRs electronically using the internet. Until such time that the state's
eDMR application is compliant with EPA's Cross-Media Electronic Reporting Regulation
(CROMERR),permittees will be required to submit all discharge monitoring data to the state
electronically using eDMR and will be required to complete the eDMR submission by printing,
signing, and submitting one signed original and a copy of the computer printed eDMR to the
following address:
NC DEQ/Division of Water Resources/Water Quality Permitting Section
ATTENTION: Central Files
1617 Mail Service Center
Raleigh,North Carolina 27699-1617
If a permittee is unable to use the eDMR system due to a demonstrated hardship or due to the facility
being physically located in an area where less than 10 percent of the households have broadband
access, then a temporary waiver from the NPDES electronic reporting requirements may be granted
and discharge monitoring data may be submitted on paper DMR forms (MR 1, 1.1, 2, 3) or
Page 4 of 6

Permit NC0020443
alternative forms approved by the Director. Duplicate signed copies shall be submitted to the
mailing address above. See "How to Request a Waiver from Electronic Reporting" section below.
Regardless of the submission method, the first DMR is due on the last day of the month following
the issuance of the permit or in the case of a new facility, on the last day of the month following the
commencement of discharge.
Starting on December 21, 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.
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: http://www2.epa.gov/compliance/final-national-pollutant-
discharge-elimination-system-npdes-electronic-reporting-rule.
Electronic submissions must start by the dates listed in the "Reporting Requirements" section above.
3. How to Request a Waiver from Electronic Reporting
The permittee may seek a temporary electronic reporting waiver from the Division. To obtain an
electronic reporting waiver, a permittee must first submit an electronic reporting waiver request to
the Division. Requests for temporary electronic reporting waivers must be submitted in writing to
the Division for written approval at least sixty(60) days prior to the date the facility would be
required under this permit to begin submitting monitoring data and reports. The duration of a
temporary waiver shall not exceed 5 years and shall thereupon expire. At such time, monitoring data
and reports shall be submitted electronically to the Division unless the permittee re-applies for and is
granted a new temporary electronic reporting waiver by the Division. Approved electronic reporting
waivers are not transferrable. Only permittees with an approved reporting waiver request may
submit monitoring data and reports on paper to the Division for the period that the approved
reporting waiver request is effective.
Page 5 of 6

Permit NC0020443
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) & Supersedes Section B. (11.)
All eDMRs submitted to the permit issuing authority shall be signed by a person described in Part II,
Section B. (11.)(a) or by a duly authorized representative of that person as described in Part II,
Section B. (11.)(b). A person, and not a position, must be delegated signatory authority for eDMR
reporting purposes.
For eDMR submissions, the person signing and submitting the DMR must obtain an eDMR user
account and login credentials to access the eDMR system. For more information on North
Carolina's eDMR system, registering for eDMR and obtaining an eDMR user account,please visit
the following web page:
hLtp://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:
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
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 6 of 6

a is STATE v ,
ROY COOPER
_ -
Governor
ELIZABETH S.BISER `•< •
Secretary
RICHARD E.ROGERS,JR. NORTH CAROLINA
Director Environmental Quality
June 09, 2022
Town of Columbia
Attn: Rhett White, Town Manager
PO Box 361
Columbia, NC 27925-0361
Subject: Permit Renewal
Application No. NCO020443
Columbia WWTP
Tyrrell County
Dear Applicant:
The Water Quality Permitting Section acknowledges the June 8, 2022 receipt of your permit renewal application and
supporting documentation. Your application will be assigned to a permit writer within the Section's NPDES WW permitting
branch. Per G.S. 150B-3 your current permit does not expire until permit decision on the application is made.
Continuation of the current permit is contingent on timely and sufficient application for renewal of the current permit. The
permit writer will contact you if additional information is required to complete your permit renewal. Please respond in a
timely manner to requests for additional information necessary to allow a complete review of the application and renewal
of the permit.
Information regarding the status of your renewal application can be found online using the Department of Environmental
Quality's Environmental Application Tracker at:
https://deg.nc.gov/permits-regulations/permit-guidance/environmental-application-tracker
If you have any additional questions about the permit, please contact the primary reviewer of the application using the
links available within the Application Tracker.
a3
ord
Administrative Assistant
Water Quality Permitting Section
ec: WQPS Laserfiche File w/application
North Carolina Department of Environmental Quality I Division of Water Resources
Washington Regional Office 1943 Washington Square Mail I Watshi gton.North Carolina 27889
^+ �� 252.946.648l

May 30,2022 RECEIVED
NCDEQ/DWR J U N U 9 2022
Attn;NPDES Unit
1617 Mail Service Center NCDEQ/DWRINPDES
Raleigh,NC 27699-1617
Subject: Request for NPDES Renewal
NPDES Permit#NC0020443
Town of Columbia
Columbia WWTP
Tyrrell County
Dear NPDES Unit:
The Town of Columbia is submitting the renewal application package for NPDES#NC0020443. The
permit expiration date is November 30,2022. The renewal application package consists of:
• Cover letter
• Renewal application Form—EPA Form 3510-2A(Revised 3-19)with tables A,B,and D
• Topographic map
• Schematic of WWTP(with waterbalance)
• Plant Narrative
• Reduced Monitoring Data
The Town would like to make the following comment regarding the permit renewal:
• The Town would like to request reduction of monitoring frequencies for BOD5,TSS,NH3 N and
Enterococci as allowed by the October 22, 2012 guidance document. We are assuming that
Enterococci monitoring reduction guidelines would be the same as those for Fecal Coliform.The
attached data(summarized in the following table)indicates that the WWTP effluent has greatly
exceeded the minimum criteria for reduced monitoring. The data used for this 3-year analysis
was for the period of December 2021—January 2019.

Analysis of testine results for the past three years:
Percent of Monthly Average Limit
Parameter Monthly Limit 3-Year Average %of Limit
BOD5 7.0 mg/t 0.9 mg/1 13.2%
TSS 30.0 mg/L 7.8 mg/L 26.0%
Enterococci 35/colonies-100ml 8.1 colonies/100ml 23%
NH3-N 2.0 mg/1 0.14 mg/l 7.0%
- Number of Samples Over 200%of Monthly Average Limit
Parameter 200%of Monthly Limit Number of Samples Over
BODS 14 mg/1 2
TSS 60 mg/L 1
NH3-N 4.0 mg./L 1
0
- Number of Samples Over 200%of Weekly Average Limit
Parameter 200%of Weekly Limit Number of Samples Over
Enterococci 552 2
In addition to the exceptional test results,the Columbia WWTP is in compliancewith all other criteria listed
in Section B Approval Criteria of the October 22,2012 guidance document regarding reduction of
monitoring frequencies.
The Town appreciates the Division's effort to reduce the regulatory and monetary burden on systems that
strive consistently to provide exceptional wastewater treatment.We thank you for your consideration in
these matters. If you have any additional questions or comments,please call contact me at:252/796-2781
or rhett—[e-mail].
Since
Rhett White,Town Manager
Town of Columbia

1 i
EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05119
110009845873 NCO020443 Columbia WWTP OMB No.2040-0004
Form U.S.Environmental Protection Agency
zA 4=0EPA Application for NPDES Permit to Discharge Wastewater
NPDES NEW AND EXISTING PUBLICLY OWNED TREATMENT WORKS
SECTION 1.BASIC APPLICATION INFORMATION FOR ALL APPLICANTS(40 CFR 122.21(j)(1)and(9))
1.1 Facility name
Columbia WWTP
Mailing address(street or P.O.box)
PO Box 361
City or town State ZIP code
o Columbia NC 27925
€ Contact name(first and last) Title Phone number Email address
Kenneth Coleson Public Works Director [phone] [e-mail]
Location address(street,route number,or other specific identifier) ❑Same as mailing address
604 N.Road Street Extension(NCSR 1209)
City or town State ZIP code
Columbia NC 27925
1.2 Is this application for a facility that has yet to commence discharge?
❑ Yes 4 See instructions on data submission ❑ No
requirements for new dischargers.
1.3 Is applicant different from entity listed under Item 1.1 above?
❑ Yes 0 No SKIP to Item 1.4.
Applicant name
Town of Columbia
Applicant address(street or P.O.box)
PO Box 361
City or town State ZIP code
Columbia NC 27925
Contact name(first and last) Title Phone number Email address
a Rhett White Town Manager [phone] rhett_townofcolumbia@yahoo
a 1.4 Is the applicant the facility's owner,operator,or both?(Check only one response.)
❑ Owner ❑ Operator Both
1.5 To which entity should the NPDES permitting authority send correspondence?(Check only one response.)
❑ Facility ❑ Applicant 0 Facility and applicant
(they are one and the same)
1.6 Indicate below any existing environmental permits.(Check all that apply and print or type the corresponding permit
number for each.
Existing Environmental Permits
CL
0 NPDES(discharges to surface ❑ RCRA(hazardous waste) ❑ UIC(underground injection
water) control)
E NCO020443
c
❑ PSD(air emissions) ❑ Nonattainment program(CAA) ❑ NESHAPs(CAA)
c
w
rn
h ❑ Ocean dumping(MPRSA) ❑ Dredge or fill(CWA Section Other(specify)
w 404)
Collection WQCS00232
EPA Form 3510-2A(Revised 3-19) Pagel

t
EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NC0020443 Columbia WWTP OMB No.2040-0004
1.7 Provide the collections stem information requested below for the treatment works.
Municipality Population Collection System Type
Served Served indicatepercentage) Ownership Status
Town of 690 100 %separate sanitary sewer 0 Own O Maintain
Z Columbia 0 %combined storm and sanitary sewer ElOwn ElMaintain
d ❑ Unknown ❑ Own ❑ Maintain
c %separate sanitary sewer ❑ Own ❑ Maintain
combined storm and sanitary sewer ❑ Own ❑ Maintain
c ❑ Unknown ElOwn ElMaintain
a %separate sanitary sewer ❑ Own ❑ Maintain
%combined storm and sanitary sewer ❑ Own ❑ Maintain
❑ Unknown ❑ Own ❑ Maintain
a; %separate sanitary sewer ❑ Own ❑ Maintain
%combined storm and sanitary sewer ❑ Own ❑ Maintain
❑ Unknown ❑ Own ❑ Maintain
Total 690
Population
0 Served
Separate Sanitary Sewer System Combined Storm and
Sanitary Sewer
Total percentage of each type of 100 % 0 %
sewer line in miles _
Z 1.8 Is the treatment works located in Indian Country?
e
'o ❑ Yes 0 No
U
- 1.9 Does the facility discharge to a receiving water that flows through Indian Country?
c ❑ Yes No
1.10 Provide design and actual flow rates in the designated spaces. Design Flow Rate
0.600 mgd
7;
Annual Average Flow Rates Actual
cc
Two Years Ago Last Year This Year
c c 0.226 mgd 0.189 mgd 0.187 mgd
U. Maximum Daily Flow Rates Actual
Two Years Ago Last Year This Year
0.838 mgd 0.679 mgd 0.742 mgd
U) 1.11 Provide the total number of effluent discharge points to waters of the United States by type.
o Total Number of Effluent Discharge Points b Type
d IL T Combined Sewer Constructed
s Treated Effluent Untreated Effluent Overflows Bypasses Emergency
Overflows
1 0 0 0 0
EPA Form 3510-2A(Revised 3-19) Page 2

EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NCO020443 Columbia W WTP OMB No.2040-0004
Outfalis Other Than to Waters of the United States
1.12 Does the POTW discharge wastewater to basins,ponds,or other surface impoundments that do not have outlets for
discharge to waters of the United States?
❑ Yes ❑✓ No 4 SKIP to Item 1.14.
1.13 Provide the location of each surface impoundment and associated discharge information in the table below.
Surface Im oundment Location and Dischar a Data
Average Daily Volume Continuous or Intermittent
Location Discharged to Surface
Impoundment
(check one)
❑ Continuous
gpd ❑ Intermittent
❑ Continuous
gpd ❑ Intermittent
❑ Continuous
H gpd ❑ Intermittent
r 1.14 Is wastewater applied to land?
❑ Yes ❑ No 4 SKIP to Item 1.16.
c 1.15 Provide the land application site and discharge data requested below.
N Land Application Site and Discharge Data
o Continuous or
`o Location Size Average Daily Volume Intermittent
o, Applied check one
acres d ❑ Continuous
0 9p ❑ Intermittent
r acres 9p d ❑ Continuous
0 ❑ Intermittent
acres d ❑ Continuous
9p ❑ Intermittent
1.16 Is effluent transported to another facility for treatment prior to discharge?
o' ElYes © No+SKIP to Item 1.21.
1.17 Describe the means by which the effluent is transported(e.g.,tank truck,pipe).
1.18 Is the effluent transported by a party other than the applicant?
❑ Yes ❑ No-* SKIP to Item 1.20.
1.19 Provide information on the transporter below.
Trans orter Data
Entity name Mailing address(street or P.O.box)
City or town State —7ZIP code
Contact name(first and last) Title
Phone number Email address
EPA Form 3510-2A(Revised 3-19) Page 3

EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NC0020443 Columbia WWTP OMB No.2040-0004
1.20 In the table below,indicate the name,address,contact information, NPDES number,and average daily flow rate of the
receiving facility.
Receiving F cility Data
Facility name Mailing address(street or P.O.box)
City or town State ZIP code
0
U
Contact name(first and last) Title
0
s
Phone number Email address
c NPDES number of receiving facility(if any) O None Average daily flow rate m d
CL 9 Y 9
fp
0 1.21 Is the wastewater disposed of in a manner other than those already mentioned in Items 1.14 through 1.21 that do not
have outlets to waters of the United States(e.g., underground percolation,underground injection)?
s ❑ Yes 0 No 4 SKIP to Item 1.23.
0 1.22 Provide information in the table below on these other disposal methods.
CDInformation on Other Disposal Methods
o Disposal Location of Size of Annual Average Continuous or Intermittent
Method Disposal Site Disposal Site Daily Discharge (check one)
cc Description Volume
y ❑ Continuous
15 acres gpd ❑ Intermittent
0
acres gpd ElContinuous
❑ Intermittent
❑ Continuous
acres gpd ❑ Intermittent
1.23 Do you intend to request or renew one or more of the variances authorized at 40 CFR 122.21(n)?(Check all that apply.
0 y Consult with your NPDES permitting authority to determine what information needs to be submitted and when.)
ElDischarges into marine waters(CWA ❑ Water quality related effluent limitation(CWA Section
Section 301(h)) 302(b)(2))
2] Not applicable
1.24 Are any operational or maintenance aspects(related to wastewater treatment and effluent quality)of the treatment works
the responsibility of a contractor?
❑ Yes ❑ No+SKIP to Section 2.
1.25 Provide location and contact information for each contractor in addition to a description of the contractor's operational
and maintenance responsibilities.
Contractor Information
Contractor 1 Contractor 2 Contractor 3
c Contractor name
(company name
Mailing address
c street or P.O.box
0 City,state,and ZIP
code
c Contact name(first and
U last
Phone number
Email address
Operational and
maintenance
responsibilities of
contractor
EPA Form 3510-2A(Revised 3-19) Page 4

EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NC0020443 Columbia W WTP OMB No.2040-0004
SECTION •• • ON 1 to
3.1 Provide the following information for each outfall.(Attach additional sheets if you have more than three outfalls.)
Outfall Number 001 Outfall Number Outfall Number
State NC
y County Tyrell
�a
0 City or town Columbia
w
0
c
.n
Distance from shore 100 ft.
Depth below surface 10 ft.
0
Average daily flow rate 0.187 mgd mgd mgd
Latitude 35° 55 18" NF-1
Longitude 7e 1� 27"' vQ "
3.2 Do any of the outfalls described under Item 3.1 have seasonal or periodic discharges?
o ❑ Yes ❑ No+ SKIP to Item 3.4.
d
3.3 If so,provide the following information for each applicable outfall.
L
N Outfall Number Outfall Number Outfall Number
0
v Number of times per year
discharge occurs
a Average duration of each
`o discharge(specify units
Average flow of each
y discharge mgd mgd mgd
co
in Months in which discharge
occurs
3.4 Are any of the outfalls listed under Item 3.1 equipped with a diffuser?
❑✓ Yes ❑ No 4 SKIP to Item 3.6.
W 3.5 Briefly describe the diffuser type at each applicable outfall.
Outfall Number 001 Outfall Number Mall Number
iv
34-ft instream diffuser
oassembly
o vi 3.6 Does the treatment works discharge or plan to discharge wastewater to waters of the United States from one or more
12 =j discharge points?
3 r ❑ Yes ❑ No+SKIP to Section 6.
EPA Form 3510-2A(Revised 3-19) Page 6

1
EPA Identification Number NPDEs Permit Number Facility Name Form Approved 03/05/19
110009845873 ENCO020443 Columbia WWTP OMB No.2040-0004
SECTION 2.ADDITIONAL INFORMATION(40 CFR 122.21(j)(1)and(2))
c Outfalls to Waters of the United States
2.1 Does the treatment works have a design flow greater than or equal to 0.1 mgd?
rn
o ❑ Yes ❑ No 4 SKIP to Section 3.
c 2.2 Provide the treatment works'current average daily volume of inflow Average Daily Volume of Inflow and Infiltration
and infiltration.
11,500 gpd
w
5 Indicate the steps the facility is taking to minimize inflow and infiltration.
c Visual observations and investigations of cleanouts and pipes. Camera investigation. Point repairs as needed.
ev
3
0
w
c
L 2.3 Have you attached a topographic map to this application that contains all the required information?(See instructions for
M CL R specific requirements.)
0g
0
0 ❑r Yes ❑ No
E 2.4 Have you attached a process flow diagram or schematic to this application that contains all the required information?
c (See instructions for specific requirements.)
_ as
R
o ❑✓ Yes ❑ No
2.5 Are improvements to the facility scheduled?
❑ Yes 0 No 4 SKIP to Section 3.
Briefly list and describe the scheduled improvements.
0
0
1.
c
E
a- 2.
E
0
h 3.
d
v
d
u 4.
U)
2.6 Provide scheduled or actual dates of completion for improvements.
Scheduled or Actual Dates of Completion for Improvements
E Affected Attainment of
d Scheduled Begin End Begin
> Outfalls Operational
o Improvement Construction Construction Discharge
E (from above) (list outfanumber)
(MM/DD/YYYY) (MM/DD/YYYY) (MM/DD/YYYY) Level
MMIDDIYYYY
d
L
N
2.
3.
4.
2.7 Have appropriate permits/clearances concerning other federal/state requirements been obtained?Briefly explain your
response.
❑ Yes ❑ No ❑ None required or applicable
Explanation:
EPA Form 3510-2A(Revised 3-19) Page 5

EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NCO020443 Columbia WWTP OMB No.2040-0004
3.7 Provide the receiving water and related information if known for each outfall.
Outfall Number 001 Outfall Number Outfall Number
Receiving water name Scuppernong River
Name of watershed,river,
Pasquotank River Basin
0 or stream system
U.S.Soil Conservation
N Service 14-digit watershed
o code
Name of state
is
management/river basin
a�
U.S.Geological Survey
8-digit hydrologic
cataloging unit code
Critical low flow(acute) cfs cfs cfs
Critical low flow(chronic) cfs cfs cfs
Total hardness at critical mg/L of mg/L of mg/L of
low flow CaCO3 CaCO3 CaCO3
3.8 Provide the following information describing the treatment pr vided for discharges from each outfall.
Outfall Number 001 Outfall Number Outfall Number
Highest Level of ❑ Primary ❑ Primary ❑ Primary
Treatment(check all that ❑ Equivalent to ❑ Equivalent to ❑ Equivalent to
apply per outfall) secondary secondary secondary
El Secondary ❑ Secondary ❑ Secondary
❑ Advanced ❑ Advanced ❑ Advanced
❑ Other(specify) ❑ Other(specify) ❑ Other(specify)
c
0
fl Design Removal Rates by
Outfall
f/1
D1
c
BOD5 or CBOD5 90 % % %
a>
E
TSS 85 % % %
0 Not applicable ❑Not applicable ❑Not applicable
Phosphorus % % °
/o
0 Not applicable ❑Not applicable ❑Not applicable
Nitrogen % % %
Other(specify) ❑Not applicable ❑Not applicable ❑Not applicable
EPA Form 3510-2A(Revised 3-19) Page 7

EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NCO020443 Columbia WWTP OMB No.2040-0004
3.9 Describe the type of disinfection used for the effluent from each outfall in the table below.If disinfection varies by
season,describe below.
v
d
c
.c
0
U
c Outfall Number 001 Outfall Number Outfall Number
0
Disinfection type Chlorination
N
d
f�
Seasons used All
d
E
r-
Dechlorination used? ❑ Not applicable ❑ Not applicable ❑ Not applicable
Z Yes ❑ Yes ❑ Yes
❑ No ❑ No ❑ No
3.10 Have you completed monitoring for all Table A parameters and attached the results to the application package?
El Yes ❑ No
3.11 Have you conducted any WET tests during the 4.5 years prior to the date of the application on any of the facility's
discharges or on any receiving water near the discharge points?
❑ Yes ❑✓ No 4 SKIP to Item 3.13.
3.12 Indicate the number of acute and chronic WET tests conducted since the last permit reissuance of the facility's
discharges by outfall number or of the receiving water near the discharge points.
Outfall Number Outfall Number Outfall Number
Acute Chronic Acute Chronic Acute Chronic
Number of tests of discharge
water
Number of tests of receiving
water
3.13 Does the treatment works have a design flow greater than or equal to 0.1 mgd?
❑ Yes ❑ No 4 SKIP to Item 3.16.
0 3.14 Does the POTW use chlorine for disinfection,use chlorine elsewhere in the treatment process,or otherwise have
reasonable potential to discharge chlorine in its effluent?
❑ Yes 4 Complete Table B,including chlorine. ❑ No 4 Complete Table B,omitting chlorine.
3.15 Have you completed monitoring for all applicable Table B pollutants and attached the results to this application
package?
w ❑✓ Yes ❑ No
3.16 Does one or more of the following conditions apply?
• The facility has a design flow greater than or equal to 1 mgd.
• The POTW has an approved pretreatment program or is required to develop such a program.
• The NPDES permitting authority has informed the POTW that it must sample for the parameters in Table C,must
sample other additional parameters(Table D),or submit the results of WET tests for acute or chronic toxicity for
each of its discharge outfalls(Table E).
Yes+Complete Tables C,D,and E as
❑ ElNo 4 SKIP to Section 4.
applicable.
3.17 Have you completed monitoring for all applicable Table C pollutants and attached the results to this application
package?
❑ Yes ❑✓ No
3.18 Have you completed monitoring for all applicable Table D pollutants required by your NPDES permitting authority and
attached the results to this application package?
No additional sampling required by NPDES
❑� Yes ❑ permitting authority.
EPA Form 3510-2A(Revised 3-19) Page 8

I
EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NCO020443 Columbia WWTP OMB No.2040-0004
3.19 Has the POTW conducted either(1)minimum of four quarterly WET tests for one year preceding this permit application
or(2)at least four annual WET tests in the past 4.5 years?
El Yes 0 No 4 Complete tests and Table E and SKIP to
Item 3.26.
3.20 Have you previously submitted the results of the above tests to your NPDES permitting authority?
❑ Yes ❑ No 4 Provide results in Table E and SKIP to
Item 3.26.
3.21 Indicate the dates the data were submitted to your NPDES permitting authority and provide a summary of the results.
Date(s)Submitted Summary of Results
MM/DDNYYY
WET Testing not Required
d
c
0
3.22 Regardless of how you provided your WET testing data to the NPDES permitting authority,did any of the tests result in
c toxicity?
c ❑ Yes ❑ No 4 SKIP to Item 3.26.
4) 3.23 Describe the cause(s)of the toxicity:
c
m
iU
W
3.24 Has the treatment works conducted a toxicity reduction evaluation?
❑ Yes ❑ No 4 SKIP to Item 3.26.
3.25 Provide details of any toxicity reduction evaluations conducted.
3.26 Have you completed Table E for all applicable outfalls and attached the results to the application package?
❑ Yes ❑ Not applicable because previously submitted
information to the NPDES ermittin authod .
SECTION 4.INDUSTRIAL DISCHARGES AND HAZARDOUS
4.1 Does the POTW receive discharges from SIUs or NSCIUs?
❑ Yes ❑✓ No 4 SKIP to Item 4.7.
d 4.2 Indicate the number of SIUs and NSCIUs that discharge to the POTW.
R Number of SIUs Number of NSCIUs
3
N
0
4.3 Does the POTW have an approved pretreatment program?
`° ❑ Yes ❑ No
x
v
R 4.4 Have you submitted either of the following to the NPDES permitting authority that contains information substantially
a� identical to that required in Table F:(1)a pretreatment program annual report submitted within one year of the
o application or(2)a pretreatment program?
M
❑ Yes ❑ No 4 SKIP to Item 4.6.
0
7i 4.5 Identify the title and date of the annual report or pretreatment program referenced in Item 4.4.SKIP to Item 4.7.
y
7
4.6 Have you completed and attached Table F to this application package?
❑ Yes ❑ No
EPA Form 3510-2A(Revised 3-19) Page 9

i
EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NC0020443 Columbia WWTP OMB No.2040-0004
4.7 Does the POTW receive,or has it been notified that it will receive,by truck,rail,or dedicated pipe,any wastes that are
regulated as RCRA hazardous wastes pursuant to 40 CFR 261?
❑ Yes 0 No 4 SKIP to Item 4.9.
4.8 If yes,provide the follo ing information:
Annual
Hazardous Waste Waste Transport Method Amount of Units
Number (check all that apply) Waste
Received
❑ Truck ❑ Rail
❑ Dedicated pipe ❑ Other(specify)
.c
0
U
d ❑ Truck ❑ Rail
❑ Dedicated pipe ❑ Other(specify)
3
O
❑ Truck ❑ Rail
_ ❑ Dedicated pipe ❑ Other(specify)
v
c
co
fN
G!
r4.9 Does the POTW receive,or has it been notified that it will receive,wastewaters that originate from remedial activities,
H including those undertaken pursuant to CERCLA and Sections 3004(7)or 3008(h)of RCRA?
0
❑ Yes 0 No 4 SKIP to Section 5.
3 4.10 Does the POTW receive(or expect to receive)less than 15 kilograms per month of non-acute hazardous wastes as
specified in 40 CFR 261.30(d)and 261.33(e)?
❑ Yes 4 SKIP to Section 5. ❑ No
4.11 Have you reported the following information in an attachment to this application:identification and description of the
site(s)or facility(ies)at which the wastewater originates;the identities of the wastewater's hazardous constituents;and
the extent of treatment,if any,the wastewater receives or will receive before entering the POTW?
❑ Yes ❑ No
SECTION • • OVERFLOWS(40
5.1 Does the treatment works have a combined sewer system?
❑ Yes ❑'' No+SKIP to Section 6.
5.2 Have you attached a CSO system map to this application?(See instructions for map requirements.)
c
1O
n El Yes ElNo
R
:E 5.3 Have you attached a CSO system diagram to this application?(See instructions for diagram requirements.)
0
N U ElYes ❑ No
EPA Form 3510-2A(Revised 3-19) Page 10

EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NC0020443 Columbia WWTP OMB No.2040-0004
5.4 For each CSO outfall,provide the following information. Attach additional sheets as necessary.)
CSO Outfall Number CSO Outfall Number CSO Outfall Number
City or town
0
State and ZIP code
o County
Latitude
0 °
0 °
c.>
Longitude
Distance from shore ft.
Depth below surface
5.5 Did the POTW monitor any of the following items in the past year for its CSO outfalls?
CSO Outfall Number CSO Outfall Number CSO Outfall Number
Rainfall ❑ Yes ❑ No ❑ Yes ❑ No ❑ Yes ❑No
rn
o CSO flow volume ❑ Yes ❑ No ❑ Yes ❑ No ❑ Yes ❑ No
CSO pollutant ❑ Yes ❑ No ❑ Yes [--] No ❑ Yes ❑ No
0 concentrations
Cn
Receiving water quality ❑Yes ❑ No ❑ Yes ❑ No ❑ Yes ❑ No
CSO frequency ❑ Yes ❑ No ❑ Yes ❑No ❑ Yes ❑ No
Number of storm events ❑ Yes ❑ No ❑ Yes [--]No ❑ Yes ❑No
5.6 Provide the following information for each of your CSO outfalls.
CSO Outfall Number CSO Outfall Number CSO Outfall Number
cc
Number of CSO events in events events events
the past year
a
c Average duration per hours hours hours
event ❑Actual or❑Estimated ❑Actual or❑ Estimated ❑Actual or❑Estimated
Uj million gallons million gallons million gallons
0 Average volume per event
i'> ❑Actual or❑Estimated ❑Actual or❑ Estimated ❑Actual or❑Estimated
Minimum rainfall causing inches of rainfall inches of rainfall inches of rainfall
a CSO event in last year ❑Actual or❑Estimated ❑Actual or❑ Estimated ❑Actual or❑ Estimated
EPA Form 3510-2A(Revised 3-19) Page 11

EPA Identification Number NPDES Permit Number Facility Name Form Approved 03/05/19
110009845873 NCO020443 Columbia WWTP OMB No.2040-0004
5.7 Provide the information in the table below for each of your CSO outfalls.
CSO Outfall Number CSO Outfall Number CSO Outfall Number
Receiving water name
Name of watershed/
streams stem
d U.S.Soil Conservation ❑Unknown ❑Unknown ❑Unknown
Service 14-digit
watershed code
> if known
Name of state
ce management/river basin
U.S.Geological Survey ❑ Unknown ❑Unknown ❑Unknown
8-Digit Hydrologic Unit
Code if known
Description of known
water quality impacts on
receiving stream by CSO
(see instructions for
examples)
SECTION • i
6.1 In Column 1 below,mark the sections of Form 2A that you have completed and are submitting with your application.For
each section,specify in Column 2 any attachments that you are enclosing to alert the permitting authority.Note that not
all applicants are required to provide attachments.
Column 1 Column 2
❑ Section 1: Basic Application El w/variance request(s) El wl additional attachments
Information for All Applicants
❑ Section 2:Additional ❑ w/topographic map 0 wl process flow diagram
Information ❑ wl additional attachments
El wl Table A 0 wl Table D
O Section 3:Information on ❑ w/Table B ❑ wl Table E
Effluent Discharges
E ❑ w/Table C ❑ wl additional attachments
R Section 4:Industrial ❑ w/SIU and NSCIU attachments ❑ wl Table F
❑ Discharges and Hazardous
Wastes ❑ w/additional attachments
❑ Section 5:Combined Sewer ❑ w/CSO map ❑ w/additional attachments
Overflows
❑ w/CSO system diagram
o Section 6:Checklist and
R Certification Statement El w/attachments
A
Y 6.2 Certification Statement
1 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 fine
and imprisonment for knowing violations.
Name(print or type first and last name) Official title
Rhett White Town Manager
Signature " Date signed
1 Z-
EPA Form 3510-2A(Revised 3-19) Page 12

EPA Identification Number NPDES Permit Number Facility Name Oudall Number Form Approved 03/05/19
110009845873 NCO020443 Columbia WWTP 001 OMB No.2040-0004
Maximum Daily Discharge Average Daily Discharge Analytical ML or MDL
Pollutant Value Units Value Units Number of Method' (include units)
Samples
Biochemical oxygen demand
a BOD5 or❑CBOD5 4.8 mg/L 0.25 mg/L 156 521OB-11 2.0 mg/L 21 MDL
(report one
Fecal coliform NA NA NA NA NA NA NA ML
13 MDL
Design flow rate 0.742 MGD 0.187 MG/I 365
pH(minimum) 6.8 S.U.
pH(maximum) 8.3 S.U.
Temperature(winter) 11.6 Celcius 10.1 Celcius 180
Temperature(summer) 25.9 Celcius 24.8 Celcius 180
Total suspended solids(TSS) 18.0 mg/L 4.9 mg/L 156 2540D-11 2.5 mg/L 0 ML
MDL
Sampling shall be conducted according to sufficiently sensitive test procedures(i.e.,methods)approved under 40 CFR 136 for the analysis of pollutants or pollutant parameters or
required under 40 CFR chapter I,subchapter N or 0.See instructions and 40 CFR 122.21(e)(3).
EPA Form 3510-2A(Revised 3-19) Page 13

This page intentionally left blank.

EPA Identification Number NPDES Permit Number Facility Name Outfall Number Form Approved 03/05119
110009845873 NCO020443 Columbia WWTP 001 OMB No.2040-0004
Pollutant
Maximum Daily Discharge Average Daily Discharge Number Analytical ML or MDL
Value Units Value Units Samples
Methods (Include units)
Ammonia(as N) 0.99 mg/L 0.10 mg/L 156 350.1 R2-93 0.04 mg/L 0 MDL
Chlorine 49.0 ug/L 21.9 ug/L 156 SM4500 Cl G-2011 10 ug/L ❑ML
total residual,TRC z ❑MDL
Dissolved oxygen 18.5 mg/L 10.48 mg/L 156 SM 4500 0 G-2016 0.1 0 MDL
Nitrate/nitrite 42.5 mg/L 26.4 mg/L 16 353.2 112-93 0.1 mg/L O MDL
Kjeldahl nitrogen 3.4 mg/L 1.5 mg/L 16 351.2 112-93 0.1 R1 MDL
Oil and grease NA NA NA NA NA NA NA ❑MDL
Phosphorus 3.4 mg/L 1.4 mg/L 16 365.4-74 0.1 O MDL
Total dissolved solids NA NA NA NA NA NA NA ❑MDL
1 Sampling shall be conducted according to sufficiently sensitive test procedures(i.e.,methods)approved under 40 CFR 136 for the analysis of pollutants or pollutant parameters or
required under 40 CFR chapter I,subchapter N or 0.See instructions and 40 CFR 122.21(e)(3).
2 Facilities that do not use chlorine for disinfection,do not use chlorine elsewhere in the treatment process,and have no reasonable potential to discharge chlorine in their effluent are not
required to report data for chlorine.
EPA Form 3510-2A(Revised 3-19) Page 15

EPA Identification Number NPDES Permit Number Facility Name Outfall Number Form Approved 03/05/19
110009845873 NC0020443 Columbia WWTP 001 OMB No.2040-0004
Maximum Dail Dischar a Average Dail Discharge Pollutant Analytical ML or MDL
(fist) Value Units Value Units Number of Method' (include units)
Samples
❑ No additional sampling is required by NPDES permitting authority.
CIVIL
Total Nitrogen 45.9 mg/L 20.1 mg/L 16 Calculated NA O MDL
OML
Enterococci 2420 100 mis 10.1 mis 156 Entero-IDX ies/100 ml 17 MDL
Mercury i U ng/L 't) ng/L 1 1631 2 ng/L OML
21 MDL
❑ML
❑MDL
O ML
❑MDL
❑ML
❑MDL
❑ML
❑MDL
❑ML
❑MDL
❑ML
❑MDL
❑ML
❑MDL
❑ML
❑MDL
❑ML
❑MDL
O ML
❑MDL
❑ML
❑MDL
❑ML
❑MDL
❑ML
❑MDL
❑ML
❑MDL
Sampling shall be conducted according to sufficiently sensitive test procedures(i.e.,methods)approved under 40 CFR 136 for the analysis of pollutants or pollutant parameters or required
under 40 CFR chapter I,subchapter N or 0.See instructions and 40 CFR 122.21(e)(3).
EPA Form 3510-2A(Revised 3-19) Page 23

1 f
Town of Wumble
n' uent Wa tewater Treatment Plant
1�.sstt;:attr p, If/ M60 604 Road St. Ext.
Columbia, NC
Grit
Removal
375,000 gal. r.v 1 315,000 gal
Oxidation ♦n"�; _
Owidition
Ditch pnU,
gKurned A.0 rated; Act
woe ,•gin
v,,,73►,yJ
65,000 gal. 65,000 gal 65,000 gill. 65,000 gal •/O A-60
Clarifier Clarifier Clanher Clarlfw
o•o�t CIAC7L tiYb Ccr
My `7 non e
a��7
Mon ►+� rtir r.wp wets,rn
Art voted
, udre
2 15hp
Centrifuge
200,000 gal. 154,000 gal. 52,000 gal. Return
Sludge Holding Sludge Holding Digester ACtivated
Tank Tank Tank Sludge
Pumps
2 50hp Verticle Turbine 2 5gph 12,000 gat.Effluent
Pumps Discharging To NaClO wastewater
300 kW The Outfall Site Fee° Holding Tank
Emergency Pumps
Generator
Ch or noted E4f uent
ti':asteti�ater

Town of Columbia Outfall Site
0,cy3406 Green St. v C'S4
Columbia, NC it
11,500 gal. 11,500 gal.
Post Post
Aeration Aeration
Basin Basin
Sodium Bisulfate
Feed Chamber
o, I V-$— '
10,000 gal.
65 kW Sodium Bisulfate
Emergency Dechlorination
Generator Tank
f2 2.5 gphfPumps
eed Diaph
2 20 hp Verticle Turbine Pumps
Discharging To The Scuppernong River
Dechiorinated Treated
ir
Wastewater
o. I$? ►^�inn

i f
Town of Columbia WWTP
Treatment Plant Narrative
NPDES#NC0020443
The Town of Columbia WWTP is a conventional wastewater treatment plant utilizing the activated
sludge process. The facility is permitted for 0.600 mgd and has an average daily flow of 0.187
mgd. The facility receives wastewater flow from the Town of Columbia.
The WWTP consists of the following major units:
• Influent flow meter
• Mechanical bar screen
• Manual bar screen (bypass)
• Aerated grit removal
• Dual oxidation ditches—375,000 gallons each
• Four secondary clarifiers —65,000 gallons each
• One RAS Tank — 10,000 gallons
• One aerated sludge holding tank—200,000 gallons
• One aerated sludge holding tank— 154,000 gallons
• One sludge digester—52,000 gallons
• Effluent pump station with Chlorination/Dechlorination dosing and chemical contact
o One chlorine contact tank— 12,000 gallons
o Two post aeration basins — 11,500 gallons each
o One dechlorination tank
• Outfall pump station
• Flow meter—effluent
• 34-ft instream effluent diffuser assembly
• Standby generator
Preliminary Treatment
As the flow enters the facility it is screened. The physical process of wastewater treatment begins
with screening out large items that have found their way into the sewer system, and if not removed,
can damage pumps and impede water flow. After passing through the screens, the flow enters the
aerated grit chamber where sand is settled. Excessive sand entering the treatment process can
cause excessive wear on pump parts,clog lines and valves, and deposit on the bottom of the basins.
The flow then goes to a splitter box which controls flow to the two oxidation ditches.

e
Secondary Treatment
From preliminary treatment the influent flows to the oxidation ditches for biological treatment.
The oxidation ditches have a capacity of 375,000 gallons each. Aeration in the ditches supplies
the oxygen necessary for biological treatment in the form of mechanical aeration and secondly,the
rotor imparts the velocity necessary to mix and move the wastewater around the ditch to the point
of discharge. The primary function of the oxidation ditches is to provide the necessary
environment and time to encourage the breakdown of any organic material (and the growth of the
bacteria), as well as ensure there is enough time for the organic material to be broken down. This
process is managed to offer the best conditions for bacterial growth.
Water is discharged from the two oxidation ditches flows into four secondary clarifiers. The
clarifiers have a capacity of 65,000 gallons each. Quiescent conditions in the clarifiers provide an
environment for the separation of solids and water. The incoming "mixed liquor" is discharged
around the periphery of each clarifier near the water surface via a narrow raceway. The settled
activated sludge is returned to the oxidation ditches(Return Activated Sludge or RAS)to increase
the bacterial concentration,help in propagation, and accelerate the breakdown of organic material.
The RAS pump rate is set to maintain a sludge blanket of approximately three feet in the clarifier.
To maintain the proper amount of activated sludge in the oxidation ditch,a portion of the settled
sludge will be removed (Waste Activated Sludge or WAS)from the treatment process by pumping
a portion of the RAS to the sludge digester.
Disinfection
The clear effluent from the clarifiers flows to the effluent holding tank from where it is chlorinated
as it is pumped to the two post aeration basins. The disinfected effluent is aerated prior to
dechlorination in the dechlorination tank.
Discharge
After dechlorination,the effluent is pumped to the Scuppernong River and is discharged via a 32-
foot diffuser assembly.
Solids Handling
Wasted activated sludge is pumped to the aerobic digester for stabilization. The stabilized sludge
will be pumped to the sludge holding tanks for addition stabilization prior to final disposal.

'•` r
,r
Outfall 001
Approximate
(with diffuser) Facility Boundary
(flows NW) _ 5
4{ i
I{ {
I! I U • 1109
J • 4
r....�. E)
0
Road Street Ext.
Downstream Sampling Point NCSR 1209
(marker#101
350 55'23"N/76° 15'40" W o>< tE)
y
Foul •,o
V.
i BI +r
Piling '• •E�,�1� I.
of 6s�s
o•
R
Y
r• �x 64 / — —• •o o ••_ i
W r
'ram
US Hwy 64 114
ju
Upstream Sampling Point C:S v •,n ®••
(US Hwy 64 Bridge]
350 55'02"N/760 15'20" W
vP NC Hwy 94
Scuppernong River
[flows northwest] eM
� �. • )tos
Town of Columbia WWTP Facility
604 N. Road Street Extension (NCSR 1209), Columbia Location '
Scale 1:24,000
eceivin¢Stream: Scuppernong River Stream Seement: 30-14-4-(9)
raina¢e Basin: Pasquotank River Basin Sub-Basin: 03-01-53
atitude: 35'55' 18" Loneitude: 76'15'27"
:ream Class: SC HUC: 03010205 North NPDES Permit NCO020443
:ate Grid/USGS Quad: D33NE/Columbia West,NC
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