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FACT SHEET
RENEWAL – NPDES PERMIT
NC0025526 – WPCS Grade WW-I [wetlands]
Table 1 - Basic Information for Permit Renewal
Permit Writer/Date Joe R. Corporon, P.G. 01Jun2023
Permit Number NC0025526
Facility Name / WWTP Class Town of Walnut Cove, 208 West Third Street /
WWTP WPCS WW-1
Facility Contacts
Mayor: Nellie Brown
Cory Willoughby, (CZO) 336-591-4809
[cwilloughby@townofwalnutcove.nc.com]
Mark Bowman, Public Works Director
[mbowman@townofwalnutcove.nc.com]
[backup ORC, CERT. WW-2]
Basin Name/Sub-basin number Roanoke River / 03-02-01
Receiving Stream Town Fork Creek [index 22-25]
Stream Classification in Permit C
Does permit need Daily Max NH3 limits? Not needed (summer limits exist)
Does permit need TRC limits/language? Existing
Does permit have toxicity testing? No
Does permit have Special Conditions? No
Does permit have instream monitoring? Yes: Temperature & D.O.
Is the stream impaired (on 303(d) list)? No
Any obvious compliance concerns? Yes, fecal coliform weekly geometric mean exceeded
on multiple occasions during last permit cycle
Any permit mods since last permit? No
Current expiration date February 28, 2022
New expiration date February 28, 2027
Comments received on Draft Permit?
Town WWTP History In 1994, the Town of Walnut Cove evaluated conventional WWTP technology
considering both mechanical and biological processes, but costs escalated above $2 million. So as
alternative, they built a combined wetlands system for approximately $1 million and began operating in
1996.
Facility - This is a Lagoon / Wetlands System. Walnut Cove WWTP treats 100% domestic wastewater
(flow 0.500 MGD) servicing a local population of 1,532 [2021].
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Treatment System Narrative: Walnut Cove’s sewerage arrives at the treatment plant lift station and is
pumped into a primary lagoon. Treatment then continues to a secondary lagoon and beyond to a
duckweed raceway. After the duckweed treatment, treated waste flows into a settling pond, and from
there is separated into two final basins. Each final basin then directs it’s flow into separate wetlands.
After the wetland systems, treated wastewaters are again reunited for the last time in a chlorine-contact
chamber where chlorine gas is applied. Treatment then concludes with dechlorination by sulfur dioxide
prior to final discharge at Town Fork Creek. A map of the flow is provided.
Receiving Stream – discharge to Town Fork Creek: Streamflow: 30Q2 = 21cfs; 7Q10w =20cfs; 7Q10s =
8.9cfs; 7Q10 Ave = 130cfs [BIMS]; a tributary to the Roanoke River (IWC = 8.01%).
Stream Evaluation (Staff Report 2012) – Early modeling indicates that the receiving stream may likely
accommodate Dissolved Oxygen (DO) loading at permitted flow levels. Town Fork Creek shows a
predictably seasonal variation in DO. Downstream (300 feet) of the WWTP discharge, DO appears to
retard somewhat, but data rarely show instream values below 5.0 mg/L. The DO sag is lowest about 3
miles downstream, but it recovers prior to the creek’s confluence with the Dan River.
Compliance History / Data Review - DMRs from 2010 and 2011 indicated that summer effluent DO
levels may measure low, at times < 3.0 mg/L. Low levels may likely result from the performance
efficiency of the lagoons and constructed wetlands. Effluent is not aerated prior to discharge.
In lieu of WET testing, the Permittee monitors Ammonia Nitrogen with Summer limits only (Winter
=>Monitor and Report) – no permit changes recommended for renewal.
BIMS data for Effluent parameters of concern (Jan2020-Mar2023) reported values generally within
permit limits except for periods of sporadic violations of Fecal Coliform limits [four (4) in 2021 and four
(4) in 2022] proceeding to NOVs and assessments. In addition, DWR cited the Permittee for TSS
Monthly Average limit violations. Other minor violations (not assessed) include monitoring frequency
(Late/Missing DMRs) - no permit changes recommended for renewal.
Summary of Changes and Rationale for Renewal
1. Instream Monitoring - DO and Temperature -- The 2016 permit requires seasonal instream
monitoring of Town Fork Creek (upstream and downstream). It further specifies Winter
monitoring at a Measurement Frequency of 3/Week and Summer monitoring Weekly. While it is
unlikely that this facility would discharge a heated effluent, instream Temperature is required to
evaluate DO – no changes recommended for renewal.
2. Effluent -- The 2016 permit does not require effluent Dissolved Oxygen (DO) monitoring.
Renewal has therefore added effluent DO and Temperature (with seasonal Measurement
Frequencies) for comparison to receiving-stream values. While it is unlikely that this facility
would discharge a heated effluent, concurrent Temperature monitoring is required to evaluate DO.
3. Ammonia Nitrogen (NH3 as N) – see WLA, May2023; limits Summer = 10.0/30.0 mg/L
(MA/DM); Winter: Monitor and Report only [see A. (1.)]. No changes recommended for renewal.
PROPOSED SCHEDULE OF ISSUANCE
Draft Permit to Public Notice: 13Jun2023 (est.)
Permit Scheduled to Issue: 21Jul2023 (est.)
Effective Date 01Sep2023 (est.)
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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. [joe.corporon@ncdenr.gov].
NAME: DATE: 01JUN2023
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 Quality Standards/Aquatic Life Protection
Parameter Acute FW, µg/l
(Dissolved)
Chronic FW, µg/l
(Dissolved)
Acute SW, µg/l
(Dissolved)
Chronic SW, µg/l
(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
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
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The Water Effects Ratio (WER) is equal to one unless determined otherwise under 15A NCAC
02B .0211 Subparagraph (11)(d)
Metal NC Dissolved Standard, µg/l
Cadmium, Acute WER*{1.136672-[ln hardness](0.041838)} ∙ e^{0.9151 [ln hardness]-
3.1485}
Cadmium, Acute Trout
waters
WER*{1.136672-[ln hardness](0.041838)} ∙ e^{0.9151[ln hardness]-
3.6236}
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[ln 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-[ln 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.
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
Page 5 of 6
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, 7Q10 (the spreadsheet automatically calculates
the 1Q10 using the formula 1Q10 = 0.843 (s7Q10, 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 (s7Q10, cfs *Avg. Upstream Hardness, mg/L)
(Permitted Flow, cfs + s7Q10, cfs)
The Combined Hardness for acute is the same but the calculation uses the 1Q10 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.
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 = (s7Q10 + Qw) (Cwqs) – (s7Q10) (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)
Page 6 of 6
Cb = background concentration: assume zero for all toxicants except NH3* (µg/L or mg/L)
Qw = permitted effluent flow (cfs, match s7Q10)
s7Q10 = 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 s7Q10 may be incorporated as applicable:
1Q10 = 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
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)
[Total as, CaCO3 or (Ca+Mg)] N/A No metals monitored
Average Upstream Hardness (mg/L)
[Total as, CaCO3 or (Ca+Mg)] N/A
7Q10 summer (cfs) 8.9 N/A
1Q10 (cfs) ~ N/A
Permitted Flow (MGD) 0.500 N/A
North Carolina
Department of Environmental Quality
Division of Water Resources
Modified Application Form 2A
Revised March 2021
Modified Application
Form 2A
Minor Sewage Facilities < 0.1 MGD
and No Pretreatment Program
NPDES Permitting Program
Note: Complete this form if your facility is a MINOR new or existing publicly owned treatment works.
NPDES Permit Number Facility Name Modified Application Form 2A
Modified March 2021
Form
NPDES
NC Department of Environmental Quality - Application for NPDES Permit to Discharge Wastewater
MINOR SEWAGE FACILITIES (Before completing this form, please read the instructions. Failure to follow
the instructions may result in denial of the application.)
SECTION 1. BASIC APPLICATION INFORMATION FOR ALL APPLICANTS (40 CFR 122.21(j)(1) and (9)) Facility Information 1.1 Facility name
Mailing address (street or P.O. box)
City or town State ZIP code
Contact name (first and last) Title Phone number Email address
Location address (street, route number, or other specific identifier) Same as mailing address
City or town State ZIP code
1.2 Is this application for a facility that has yet to commence discharge?
Yes See instructions on data submission Norequirements for new dischargers. Applicant Information 1.3 Is applicant different from entity listed under Item 1.1 above?
Yes No SKIP to Item 1.4.
Applicant name
Applicant address (street or P.O. box)
City or town State ZIP code
Contact name (first and last) Title Phone number Email address
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 and applicantFacility Applicant (they are one and the same)Existing Environmental Permits 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
NPDES (discharges to surfacewater)
_________________________
RCRA (hazardous waste)
_________________________
UIC (underground injectioncontrol)
_______________________
PSD (air emissions)
_________________________
Nonattainment program (CAA)
_________________________
NESHAPs (CAA)
_______________________
Ocean dumping (MPRSA)
_________________________
Dredge or fill (CWA Section404)
_________________________
Other (specify)
_______________________
Page 1
NPDES Permit Number Facility Name Collection System and Population Served 1.7 Provide the collection system information requested below for the treatment works.
Municipality Served Population Served Collection System Type
(indicate percentage) Ownership Status
_____ % separate sanitary sewer
_____ % combined storm and sanitary sewer
Unknown
Own Maintain
Own Maintain
Own Maintain
_____ % separate sanitary sewer
_____ % combined storm and sanitary sewer
Unknown
Own Maintain
Own Maintain
Own Maintain
_____ % separate sanitary sewer
_____ % combined storm and sanitary sewer
Unknown
Own Maintain
Own Maintain
Own Maintain
_____ % separate sanitary sewer
_____ % combined storm and sanitary sewer
Unknown
Own Maintain
Own Maintain
Own Maintain
Total Population
Served
Total percentage of each type of
sewer line (in miles)
Separate Sanitary Sewer System Combined Storm and Sanitary Sewer
% % Indian Country1.8 Is the treatment works located in Indian Country?
Yes No
1.9 Does the facility discharge to a receiving water that flows through Indian Country?
Yes No
Design and ActualFlow Rates 1.10 Provide design and actual flow rates in the designated spaces. Design Flow Rate
mgd
Annual Average Flow Rates (Actual)
Two Years Ago Last Year This Year
mgd mgd mgd
Maximum Daily Flow Rates (Actual)
Two Years Ago Last Year This Year
mgd mgd mgd Discharge Points by Type 1.11 Provide the total number of effluent discharge points to waters of the State of North Carolina by type.
Total Number of Effluent Discharge Points by Type
Treated Effluent Untreated Effluent Combined Sewer
Overflows Bypasses Constructed Emergency
Overflows
Page 2
Modified Application Form 2A
Modified March 2021
NPDES Permit Number Facility Name Outfalls and Other Discharge or Disposal Methods Outfalls Other Than to Waters of the State of North Carolina
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 State of North Carolina?
Yes No SKIP to Item 1.14.
1.13 Provide the location of each surface impoundment and associated discharge information in the table below.
Surface Impoundment Location and Discharge Data
Location Average Daily Volume Discharged to Surface
Impoundment
Continuous or Intermittent
(check one)
gpd Continuous
Intermittent
gpd Continuous
Intermittent
gpd Continuous
Intermittent
1.14 Is wastewater applied to land?
Yes No SKIP to Item 1.16.
1.15 Provide the land application site and discharge data requested below.
Land Application Site and Discharge Data
Location Size Average Daily Volume
Applied
Continuous or Intermittent
(check one)
acres gpd Continuous
Intermittent
acres gpd Continuous
Intermittent
acres gpd Continuous
Intermittent
1.16 Is effluent transported to another facility for treatment prior to discharge?
Yes 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.
Transporter Data
Entity name Mailing address (street or P.O. box)
City or town State ZIP code
Contact name (first and last) Title
Phone number Email address
Page 3
Modified Application Form 2A
Modified March 2021
NPDES Permit Number Facility Name Outfalls and Other Discharge or Disposal Methods Continued 1.20 In the table below, indicate the name, address, contact information, NPDES number, and average daily flow rate of the
receiving facility.
Receiving Facility Data
Facility name Mailing address (street or P.O. box)
City or town State ZIP code
Contact name (first and last) Title
Phone number Email address
NPDES number of receiving facility (if any) None Average daily flow rate mgd
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 State of North Carolina (e.g., underground percolation, underground injection)?
Yes No SKIP to Item 1.23.
1.22 Provide information in the table below on these other disposal methods.
Information on Other Disposal Methods
Disposal Method Description
Location of Disposal Site Size of Disposal Site
Annual Average Daily Discharge Volume
Continuous or Intermittent
(check one)
acres gpd Continuous
Intermittent
acres gpd Continuous
Intermittent
acres gpd Continuous
Intermittent
Variance Requests 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.
Consult with your NPDES permitting authority to determine what information needs to be submitted and when.)
Discharges into marine waters (CWA Water quality related effluent limitation (CWA Section Section 301(h)) 302(b)(2))
Not applicable
Contractor Information 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
Contractor name
(company name)
Mailing address
(street or P.O. box)
City, state, and ZIP
code
Contact name (first and
last)
Phone number
Email address
Operational and
maintenance
responsibilities of
contractor
Page 4
Modified Application Form 2A
Modified March 2021
NPDES Permit Number Facility Name
SECTION 2. ADDITIONAL INFORMATION (40 CFR 122.21(j)(1) and (2)) Design FlowOutfalls to Waters of the State of North Carolina
2.1 Does the treatment works have a design flow greater than or equal to 0.1 mgd?
Yes No SKIP to Section 3.Inflow and Infiltration2.2 Provide the treatment works’ current average daily volume of inflow
and infiltration.
Average Daily Volume of Inflow and Infiltration
gpd
Indicate the steps the facility is taking to minimize inflow and infiltration. TopographicMap 2.3 Have you attached a topographic map to this application that contains all the required information? (See instructions for
specific requirements.)
Yes No
FlowDiagram2.4 Have you attached a process flow diagram or schematic to this application that contains all the required information?
(See instructions for specific requirements.)
Yes No
Scheduled Improvements and Schedules of Implementation 2.5 Are improvements to the facility scheduled?
Yes No SKIP to Section 3.
Briefly list and describe the scheduled improvements.
1.
2.
3.
4.
2.6 Provide scheduled or actual dates of completion for improvements.
Scheduled or Actual Dates of Completion for Improvements
Scheduled Improvement
(from above)
Affected Outfalls
(list outfall
number)
Begin Construction
(MM/DD/YYYY)
End Construction
(MM/DD/YYYY)
Begin Discharge
(MM/DD/YYYY)
Attainment of Operational
Level
(MM/DD/YYYY)
1.
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:
Page 5
Modified Application Form 2A
Modified March 2021
NPDES Permit Number Facility Name
Waters of Diffuser Type Seasonal or Periodic Discharge Data Description of Outfalls the U.S. SECTION 3. INFORMATION ON EFFLUENT DISCHARGES (40 CFR 122.21(j)(3) to (5))
3.1 Provide the following information for each outfall. (Attach additional sheets if you have more than three outfall s.)
Outfall Number ______ Outfall Number _____ Outfall Number ______
State
County
City or town
Di stance from shore ft. ft. ft.
Depth below surface ft. ft. ft.
Average daily flow rate mgd mgd mgd
Lati tude ° ’ ” ° ’ ” ° ’ ”
Longitude ° ’ ” ° ’ ” ° ’ ”
3.2 Do any of the outfalls described under Item 3.1 have seasonal or peri odic discharges?
Yes No SKIP to Item 3.4.
3.3 If so, provide the following informati on for each applicable outfall.
Outfall Number _____ Outfall Number _____ Outfall Number _____
Number of ti mes per year discharge occurs
Average duration of each discharge (specify units)
Average flow of each mgd mgd mgd discharge
Months in which discharge
occurs
3.4 Are any of the outfalls li sted under Item 3.1 equipped with a diffuser?
Yes No SKIP to Item 3.6.
3.5 Briefly describe the diffuser type at each applicable outfall.
Outfall Number _____ Outfall Number _____ Outfall Number _____
3.6
Does the treatment works discharge or plan to discharge wastewater to waters of the State of North Carolina from
one or more discharge points?
Yes No SKIP to Section 6.
Page 6
Modified Application Form 2A
Modified March 2021
NPDES Permit Number Facility Name Receiving Water Description 3.7 Provide the receiving water and related information (if known) for each outfall.
Outfall Number _____ Outfall Number _____ Outfall Number _____
Receiving water name
Name of watershed, river,
or stream system
U.S. Soil Conservation
Service 14-digit watershed
code
Name of state
management/river basin
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
low flow
mg/L of
CaCO3
mg/L of
CaCO3
mg/L of
CaCO3 Treatment Description 3.8 Provide the following information describing the treatment provided for discharges from each outfall.
Outfall Number _____ Outfall Number _____ Outfall Number _____
Highest Level of Treatment (check all that
apply per outfall)
Primary
Equivalent to
secondary
Secondary
Advanced
Other (specify)
__________________
Primary
Equivalent to
secondary
Secondary
Advanced
Other (specify)
___________________
Primary
Equivalent to
secondary
Secondary
Advanced
Other (specify)
_________________
Design Removal Rates by
Outfall
BOD5 or CBOD5 % % %
TSS % % %
Phosphorus Not applicable
%
Not applicable
%
Not applicable
%
Nitrogen Not applicable
%
Not applicable
%
Not applicable
%
Other (specify)
______________________
Not applicable
%
Not applicable
%
Not applicable
%
Page 7
Modified Application Form 2A
Modified March 2021
NPDES Permit Number Facility Name Treatment Description Continued 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.
Outfall Number _____ Outfall Number _____ Outfall Number _____
Disinfection type
Seasons used
Dechlorination used? Not applicable
Yes
No
Not applicable
Yes
No
Not applicable
Yes
No
Effluent Testing Data 3.10 Have you completed monitoring for all Table A parameters and attached the results to the application package?
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 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
3.14 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 Complete Table B, including chlorine.No 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?
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 NPDESYes permitting authority.
Page 8
Modified Application Form 2A
Modified March 2021
NPDES Permit Number Facility Name Effluent Testing Data Continued 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?
No Complete tests and Table E and SKIP toYes Item 3.26.
3.20 Have you previously submitted the results of the above tests to your NPDES permitting authority?
No Provide results in Table E and SKIP toYes 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
(MM/DD/YYYY) Summary of Results
3.22 Regardless of how you provided your WET testing data to the NPDES permitting authority, did any of the tests result in
toxicity?
Yes No SKIP to Item 3.26.
3.23 Describe the cause(s) of the toxicity:
3.24 Has the treatment works conducted a toxicity reduction evaluation?
Yes No 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?
Not applicable because previously submittedYes information to the NPDES permitting authority.
Page 9
Modified Application Form 2A
Modified March 2021
SECTION 6. CHECKLIST AND CERTIFICATION STATEMENT (40 CFR 122.22(a) and (d)) Checklist and Certification Statement 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 ApplicationInformation for All Applicants w/ variance request(s)w/ additional attachments
Section 2: AdditionalInformation
w/ topographic map w/ process flow diagram
w/ additional attachments
Section 3: Information onEffluent Discharges
w/ Table A w/ Table D
w/ additional attachments
Section 4: Not Applicable
Section 5: Not Applicable
Section 6: Checklist andCertification Statement w/ attachments
6.2 Certification Statement
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 fine
and imprisonment for knowing violations.
Name (print or type first and last name) Official title
Signature Date signed
Page 10
NPDES Permit Number Facility Name
w/ Table B
w/ Table C
Modified Application Form 2A
Modified March 2021
NPDES Permit Number Facility Name Outfall Number
TABLE A. EFFLUENT PARAMETERS FOR ALL POTWS
Maximum Daily Discharge Average Daily Discharge Analytical ML or MDL Pollutant Number of Method1 Value Units Value Units (incl ude units) Samples
Biochemi cal oxygen demand ML BOD5 or CBOD5 MDL (report one)
ML Fecal coliform MDL
Desi gn flow rate
pH (mini mum)
pH (maxi mum)
Temperature (wi nter)
Temperature (summer)
ML Total suspended solids (TSS) 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 O. See instructions and 40 CFR 122.21(e)(3).
Page 11
Modified Application Form 2A
Modified March 2021
EPA Identification Number NPDES Permit Number Facility Name Outfall Number
TABLE B. EFFLUENT PARAMETERS FOR ALL POTWS WITH A FLOW EQUAL TO OR GREATER THAN 0.1 MGD
Pollutant
Maximum Daily Discharge Average Daily Discharge Analytical
Method1
ML or MDL
(include units) Value Units Value Units Number of
Samples
Ammonia (as N) ML
MDL
Chlorine
(total residual, TRC)2
ML
MDL
Dissolved oxygen ML
MDL
Nitrate/nitrite ML
MDL
Kjeldahl nitrogen ML
MDL
Oil and grease ML
MDL
Phosphorus ML
MDL
Total dissolved solids ML
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 O. 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 12
Modified Application Form 2A
Modified March 2021
EPA Identification Number NPDES Permit Number Facility Name Outfall Number
TABLE C. EFFLUENT PARAMETERS FOR SELECTED POTWS
Pollutant
Maximum Daily Discharge Average Daily Discharge Analytical
Method1
ML or MDL
(include units) Value Units Value Units Number of
Samples
Metals, Cyanide, and Total Phenols
Hardness (as CaCO3) ML
MDL
Antimony, total recoverable ML
MDL
Arsenic, total recoverable ML
MDL
Beryllium, total recoverable ML
MDL
Cadmium, total recoverable ML
MDL
Chromium, total recoverable ML
MDL
Copper, total recoverable ML
MDL
Lead, total recoverable ML
MDL
Mercury, total recoverable ML
MDL
Nickel, total recoverable ML
MDL
Selenium, total recoverable ML
MDL
Silver, total recoverable ML
MDL
Thallium, total recoverable ML
MDL
Zinc, total recoverable ML
MDL
Cyanide ML
MDL
Total phenolic compounds ML
MDL
Volatile Organic Compounds
Acrolein ML
MDL
Acrylonitrile ML
MDL
Benzene ML
MDL
Bromoform ML
MDL
EPA Form 3510-2A (Revised 3-19) Page 13
Modified Application Form 2A
Modified March 2021
EPA Identification Number NPDES Permit Number Facility Name Outfall Number
TABLE C. EFFLUENT PARAMETERS FOR SELECTED POTWS
Pollutant
Maximum Daily Discharge Average Daily Discharge Analytical
Method1
ML or MDL
(include units) Value Units Value Units Number of
Samples
Carbon tetrachloride ML
MDL
Chlorobenzene ML
MDL
Chlorodibromomethane ML
MDL
Chloroethane ML
MDL
2-chloroethylvinyl ether ML
MDL
Chloroform ML
MDL
Dichlorobromomethane ML
MDL
1,1-dichloroethane ML
MDL
1,2-dichloroethane ML
MDL
trans-1,2-dichloroethylene ML
MDL
1,1-dichloroethylene ML
MDL
1,2-dichloropropane ML
MDL
1,3-dichloropropylene ML
MDL
Ethylbenzene ML
MDL
Methyl bromide ML
MDL
Methyl chloride ML
MDL
Methylene chloride ML
MDL
1,1,2,2-tetrachloroethane ML
MDL
Tetrachloroethylene ML
MDL
Toluene ML
MDL
1,1,1-trichloroethane ML
MDL
1,1,2-trichloroethane ML
MDL
EPA Form 3510-2A (Revised 3-19) Page 14
Modified Application Form 2A
Modified March 2021
EPA Identification Number NPDES Permit Number Facility Name Outfall Number
TABLE C. EFFLUENT PARAMETERS FOR SELECTED POTWS
Pollutant
Maximum Daily Discharge Average Daily Discharge Analytical
Method1
ML or MDL
(include units) Value Units Value Units Number of
Samples
Trichloroethylene ML
MDL
Vinyl chloride ML
MDL
Acid-Extractable Compounds
p-chloro-m-cresol ML
MDL
2-chlorophenol ML
MDL
2,4-dichlorophenol ML
MDL
2,4-dimethylphenol ML
MDL
4,6-dinitro-o-cresol ML
MDL
2,4-dinitrophenol ML
MDL
2-nitrophenol ML
MDL
4-nitrophenol ML
MDL
Pentachlorophenol ML
MDL
Phenol ML
MDL
2,4,6-trichlorophenol ML
MDL
Base-Neutral Compounds
Acenaphthene ML
MDL
Acenaphthylene ML
MDL
Anthracene ML
MDL
Benzidine ML
MDL
Benzo(a)anthracene ML
MDL
Benzo(a)pyrene ML
MDL
3,4-benzofluoranthene ML
MDL
EPA Form 3510-2A (Revised 3-19) Page 15
Modified Application Form 2A
Modified March 2021
EPA Identification Number NPDES Permit Number Facility Name Outfall Number
TABLE C. EFFLUENT PARAMETERS FOR SELECTED POTWS
Pollutant
Maximum Daily Discharge Average Daily Discharge Analytical
Method1
ML or MDL
(include units) Value Units Value Units Number of
Samples
Benzo(ghi)perylene ML
MDL
Benzo(k)fluoranthene ML
MDL
Bis (2-chloroethoxy) methane ML
MDL
Bis (2-chloroethyl) ether ML
MDL
Bis (2-chloroisopropyl) ether ML
MDL
Bis (2-ethylhexyl) phthalate ML
MDL
4-bromophenyl phenyl ether ML
MDL
Butyl benzyl phthalate ML
MDL
2-chloronaphthalene ML
MDL
4-chlorophenyl phenyl ether ML
MDL
Chrysene ML
MDL
di-n-butyl phthalate ML
MDL
di-n-octyl phthalate ML
MDL
Dibenzo(a,h)anthracene ML
MDL
1,2-dichlorobenzene ML
MDL
1,3-dichlorobenzene ML
MDL
1,4-dichlorobenzene ML
MDL
3,3-dichlorobenzidine ML
MDL
Diethyl phthalate ML
MDL
Dimethyl phthalate ML
MDL
2,4-dinitrotoluene ML
MDL
2,6-dinitrotoluene ML
MDL
EPA Form 3510-2A (Revised 3-19) Page 16
Modified Application Form 2A
Modified March 2021
EPA Identification Number NPDES Permit Number Facility Name Outfall Number
TABLE C. EFFLUENT PARAMETERS FOR SELECTED POTWS
Pollutant
Maximum Daily Discharge Average Daily Discharge Analytical
Method1
ML or MDL
(include units) Value Units Value Units Number of
Samples
1,2-diphenylhydrazine ML
MDL
Fluoranthene ML
MDL
Fluorene ML
MDL
Hexachlorobenzene ML
MDL
Hexachlorobutadiene ML
MDL
Hexachlorocyclo-pentadiene ML
MDL
Hexachloroethane ML
MDL
Indeno(1,2,3-cd)pyrene ML
MDL
Isophorone ML
MDL
Naphthalene ML
MDL
Nitrobenzene ML
MDL
N-nitrosodi-n-propylamine ML
MDL
N-nitrosodimethylamine ML
MDL
N-nitrosodiphenylamine ML
MDL
Phenanthrene ML
MDL
Pyrene ML
MDL
1,2,4-trichlorobenzene ML
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 O. See instructions and 40 CFR 122.21(e)(3).
EPA Form 3510-2A (Revised 3-19) Page 17
Modified Application Form 2A
Modified March 2021
NPDES Permit Number Facility Name Outfall Number
TABLE D. ADDITIONAL POLLUTANTS AS REQUIRED BY NPDES PERMITTING AUTHORITY
Pollutant
(list)
Maximum Daily Discharge Average Daily Discharge Analytical Method1
ML or MDL
(include units) Value Units Value Units Number of Samples
No additional sampling is required by NPDES permitting authority.
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
MDL
ML
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 O. See instructions and 40 CFR 122.21(e)(3).
Page 18
Modified Application Form 2A
Modified March 2021