NC0036196_Modification_20240805

Docusign Envelope ID: DD8EF4B2-05D8-4B84-BC29-D909536D13E5
STATE
ROY COOPER v o
Governor
ELIZABETH S.BISER -x`nxi as
Secretary
RICHAM E.ROGERS,JR. NORTH CAROLINA
Director Environmental Quality
August 5,2024
Mr. Eric Jones
WWTP Superintendent
City of Newton
P.O. Box 550
Newton,North Carolina 28658
Subject: Final NPDES Permit Modification
Permit NCO036196
Clark Creek WWTP
Catawba County
Grade IV Biological WPCS
SIC Code 4495
Dear Mr. Jones:
Having considered the City of Newton's request to modify NPDES permit NCO036196 to reevaluate the
City's Total Aluminum limitations, as they are believed to be calculated in error, the Division of Water
Resources is issuing the modification and forwarding herewith the modified permit for the Clark Creek
WWTP. This permit is issued pursuant to the requirements of North Carolina General Statute 143- 215.1
and the Memorandum of Agreement between North Carolina and the U.S. Environmental Protection
Agency dated October 15, 2007 (or as subsequently amended).
The Division published notice of the draft permits on June 13,2024 in Observer News Enterprise inviting
public comment on the proposed modifications for a 30- day period. No changes were made to the draft
version of the permit.
The Clark Creek WWTP' s final permit includes the following changes:
• Total Aluminum Limit Removal. Review of the existing total aluminum limitations found that an
outdated EPA Nationally Recommended Water Quality Criterion (NRWQC) was used for
assessment of need for total aluminum limitations.As the EPA revised their NRWQC in 2018,the
outdated value should not have been used.The use of the outdated value is considered a"technical
mistakes or mistaken interpretations of law"and is an exception to the antibacksliding rule per 40
CFR 122.44(l)(2)(i)(13)(2). As such,the limits in the permit have been removed.
• Total Aluminum Aquatic Life Assessment. To evaluate total aluminum in accordance with the
2018 EPA NRWQC,quarterly monitoring for upstream pH and DOC has been added to the permit.
Total aluminum monitoring is required in the permit at a quarterly frequency. Monitoring for
upstream hardness, pH and DOC and effluent total aluminum shall be conducted in conjunction
with quarterly chronic toxicity testing.
If any parts,measurement frequencies or sampling requirements contained in this permit are unacceptable
to you,you have the right to an adjudicatory hearing upon written request within thirty(30)days following
receipt of this letter. This request must be in the form of a written petition, conforming to Chapter 150B of
the North Carolina General Statutes, and filed with the Office of Administrative Hearings (6714 Mail
Service Center,Raleigh,North Carolina 27699-6714).Unless such demand is made,this decision shall be
final and binding.
E Q�� North Carolina Department of Environmental Quality I Division of Water Resources
4512 North Salisbury Street 11611 Mail Service Center I Raleigh,North Carolina 27699-1611
NO CARO�INA _
DeperVneM of EnWronmenGl puall 919'707'9000

Docusign Envelope ID: DD8EF4B2-05D8-4B84-BC29-D909536D13E5
Please note that this permit is not transferable except after notice to the Division. The Division may require
modification or revocation and reissuance of the permit. This permit does not affect the legal requirements
to obtain other permits which may be required by the Division of Water Resources or any other Federal,
State, or Local governmental regulations.
If you have any questions concerning this permit,please contact Nick Coco at(919)707-3609 or via email
at [e-mail].
Sincerely,
DocuSigned by* `',&In.''`
C4545314315 44FE...
Michael J. Montebello
NPDES Permitting Branch Chief
Division of Water Resources,NCDEQ
Hardcopy: NPDES Files
Central Files
Ecopy: US EPA Region 4
DWR/Mooresville Regional Office/Water Quality/Andrew Pitner& Wes Bell
E Q�� North Carolina Department of Environmental Quality I Division of Water Resources
4512 North Salisbury Street 11611 Mail Service Center I Raleigh,North Carolina 27699-1611
NO CARO�INA _
DeperVneM of EnWronmenGl puall 919'707'900(]

Docusign Envelope ID: DD8EF4B2-05D8-4B84-BC29-D909536D13E5
Permit NCO036196
PART
A.(1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS [5.0 MGD]
[15A NCAC 02B .0400 et seq., 15A NCACO2B .0500 et seq.] Grade IV
Biological Water Pollution Control System [15A NCAC 08G .0302]
a. During the period beginning on the effective date of the permit and lasting until expansion above
5.0 MGD or permit expiration,whichever comes first, the permittee is authorized to discharge
treated wastewater from Outfall 001. Such discharges shall be limited and monitored'by the
permittee asspecified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
PARAMETER
Parameter Code Monthly Weekly Daily Measurement Sample Sample
Average Average Maximum Frequency Type Location
Flow 50050 5.0 MGD Continuous Recording I or E
BOD, 5 day, 20°C3 C0310 15.0 mg/L 22.5 mg/L Daily Composite I and E
(April 1-October 31)
BOD, 5 day, 20°C3 C0310 30.0 mg/L 45.0 mg/L Daily Composite I and E
(November 1- March 31)
Total Suspended Solids3 C0530 30.0 mg/L 45.0 mg/L Daily Composite I and E
NH3 as N C0610 1.6 mg/L 4.8 mg/L Daily Composite E
(April 1-October 31)
NH3 as N C0610 3.8 mg/L 11.4 mg/L Daily Composite E
(November 1- March 31)
Fecal Coliform 31616 200/100 mL 400/100 mL Daily Grab E
(geometric mean)
Dissolved Oxygen 00300 Daily Average >_ 5.0 mg/L Daily Grab E
pH 00400 Between 6.0 and 9.0 Standard Units Daily Grab E
Total Residual Chlorine 50060 1 1 28 pg/L Daily Grab E
Temperature, °C 00010 Monitor and Report Daily Grab E
Conductivity, pmhos/cm 00094 Monitor and Report Daily Grab E
Total Nitrogen, mg/L C0600 Monitor and Report Monthly Composite E
Total Phosphorous, mg/L C0665 Monitor and Report Monthly Composite E
Total Aluminum, pg/LS 01105 Monitor and Report Quarterly Composite E
Total Copper 01042 46.0 dig/L 67.1 pg/L Monthly Composite E
Total Hardness [as CaC031, mg/L6 00900 Monitor and Report Quarterly Grab E
Chronic Toxicity' TGP3B Monitor and Report Quarterly Composite E
Effluent Pollutant Scan$ NC01 Monitor and Report Footnote 8 Footnote 8 E
Dissolved Oxygen (mg/L) 00300 Monitor and Report Variable' Grab U and D
Temperature°C 00010 Monitor and Report Variable' Grab U and D
Conductivity, pmhos/cm 00094 Monitor and Report Variable' Grab U and D
Fecal Coliform, #/100mL 31616 Monitor and Report Variable' Grab U and D
pH,s.u.s 00400 Monitor and Report Quarterly Grab U
Dissolved Organic Carbon, mg/1-5 00681 Monitor and Report Quarterly Grab U
Total Hardness [as CaC031, mg/L5,9 00900 Monitor and Report Quarterly Grab U
Footnotes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR application system. See Special
Condition A.(6.).
2. Sample locations I-Influent,E-Effluent,U-Upstream at NCSR 2014,D-Downstream at NCSR 2007. Upstream and downstream
samples shall be grab samples collected 3/week during June,July,August,and September and 1/week during the remainder of
the year.
3. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed 15%of the respective influent
value(85%removal).
DocuSigned by:
(Footnotes continued on next page.) E( WK k�
Page 3 of 13 C464631431644FE...
Michael Montebello,NPDES Branch Chief
Modification Effective Date: August 5,2024

Docusign Envelope ID: DD8EF4B2-05D8-4B84-BC29-D909536D13E5
Permit NCO036196
Footnotes(continued)_
4. The Division shall consider all effluent total residual chlorine values reported below 50 µg/L to be in compliance with the
permit.However,the permittee shall continue to record and submit all values reported by a North Carolina certified laboratory
(including field certified),even if these values fall below 50 µg/L.
5. Effluent Total Aluminum and Upstream pH,Dissolved Organic Carbon and Hardness sampling shall be conducted in
conjunction with chronic toxicity testing.
6. Effluent hardness sampling should be performed in conjunction with testing for hardness dependent metals(cadmium,copper,
lead,nickel,silver,and zinc).
7. Chronic Toxicity(Ceriodaphnia dubia)P/F at 56%with testing in March,June,September and December.See Special Condition
A.(3.).
8. The permittee shall perform three effluent pollution scans during the term of this permit.See Special Condition A.(4.).
9. The Permittee shall sample instream hardness,upstream of the facility's discharge.The sample shall be representative of the
hardness in the receiving stream.
b. There shall be no discharge of floating solids or visible foam in other than trace amounts.
DocuSigned byy:qq 6 ..''''AA
Page 4 of 13 C464531431644FE_
Michael Montebello,NPDES Branch Chief
Modification Effective Date: August 5,2024

Docusign Envelope ID: DD8EF4B2-05D8-4B84-BC29-D909536D13E5
Permit NCO036196
A.(2.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS [7.5 MGD]
[15A NCAC 02B .0400 et seq., 15A NCACO2B .0500 et seq.] Grade IV
Biological Water Pollution Control System [15A NCAC 08G .0302]
a. Beginning upon receipt of the Engineer's Certification for completion of the expansion to 7.5
MGD and lasting until permit expiration,the Permittee is authorized to discharge treated
wastewater from Outfall 001. Such discharges shall be limited and monitored'by the Permittee as
specified below:
EFFLUENT LIMITS MONITORING REQUIREMENTS
PARAMETER
Monthly Weekly Daily Measurement Sample Sample
Parameter Code Average Average Maximum Frequency Type Location
Flow 50050 7.5 MGD Continuous Recording I or E
BOD, 5 day, 20°C
(March 1-October 31) C0310 15.0 mg/L 22.5 mg/L Daily Composite I and E
BOD, 5 day, 20°C3 C0310 30.0 mg/L 45.0 mg/L Daily Composite I and E
(November 1- February 28/29)
Total Suspended Solids3 C0530 30.0 mg/L 45.0 mg/L Daily Composite I and E
NH3 as N
(March 1 October 31) C0610 1.4 mg/L 4.2 mg/L Daily Composite E
NH3 as N
(November 1- February 28/29) C0610 3.2 mg/L 9.6 mg/L Daily Composite E
Fecal Coliform 31616 200/100 mL 400/100 mL Daily Grab E
(geometric mean)
Dissolved Oxygen 00300 Daily Average >_ 5.0 mg/L Daily Grab E
pH 00400 Between 6.0 and 9.0 Standard Units Daily Grab E
Total Residual Chlorine 50060 1 1 26 lag/L Daily Grab E
Temperature,°C 00010 Monitor and Report Daily Grab E
Conductivity, pmhos/cm 00094 Monitor and Report Daily Grab E
Total Nitrogen, mg/L C0600 Monitor and Report Monthly Composite E
Total Phosphorous, mg/L C0665 Monitor and Report Monthly Composite E
Total Aluminum, lag/L5 01105 Monitor and Report Quarterly Composite E
Total Copper 01042 42.9 lag/L 1 1 63.1 lag/L Monthly Composite E
Total Hardness[as CaC031, mg/L6 00900 Monitor and Report Quarterly Grab E
Chronic Toxicity? TGP38 Monitor and Report Quarterly Composite E
Effluent Pollutant Scan$ NC01 Monitor and Report Footnote 7 Footnote 7 E
Dissolved Oxygen (mg/L) 00300 Monitor and Report Variable Grab U and D
Temperature°C 00010 Monitor and Report Variable Grab U and D
Conductivity, pmhos/cm 00094 Monitor and Report Variable Grab U and D
Fecal Coliform, #/100mL 31616 Monitor and Report Variablez Grab U and D
pH,s.u.s 00400 Monitor and Report Quarterly Grab U
Dissolved Organic Carbon, mg/L5 00681 Monitor and Report Quarterly Grab U
Total Hardness[as CaC031, mg/L5.9 00900 Monitor and Report Quarterly Grab U
Footnotes:
1. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR application system. See Special
Condition A.(6.).
2. Sample locations I-Influent,E-Effluent,U-Upstream at NCSR 2014,D-Downstream at NCSR 2007. Upstream and downstream
samples shall be grab samples collected 3/week during June,July,August,and September and 1/week during the remainder of
the year.
3. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed 15%of the respective influent
value(85%removal).
(Footnotes continued on next page.) Doc/IuSigne/Id by:
IVU(UA�I At6VUtbW,6
Page 5 of 13 C464531431644FE.
Michael Montebello,NPDES Branch Chief
Modification Effective Date: August 5,2024

Docusign Envelope ID: DD8EF4B2-05D8-4B84-BC29-D909536D13E5
Permit NCO036196
Footnotes(continued)_
4. The Division shall consider all effluent total residual chlorine values reported below 50 µg/L to be in compliance with the
permit.However,the permittee shall continue to record and submit all values reported by a North Carolina certified laboratory
(including field certified),even if these values fall below 50 µg/L.
5. Effluent Total Aluminum and Upstream pH,Dissolved Organic Carbon and Hardness sampling shall be conducted in
conjunction with chronic toxicity testing.
6. Effluent hardness sampling should be performed in conjunction with testing for hardness dependent metals(cadmium,copper,
lead,nickel,silver,and zinc).
7. Chronic Toxicity(Ceriodaphnia dubia)P/F at 66%with testing in March,June,September and December.See Special Condition
A.(3.).
8. The permittee shall perform three effluent pollution scans during the term of this permit.See Special Condition A.(4.).
9. The Permittee shall sample instream hardness,upstream of the facility's discharge.The sample shall be representative of the
hardness in the receiving stream.
b. There shall be no discharge of floating solids or visible foam in other than trace amounts.
A.(3.) CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY)
[15A NCAC 02B.0200]
The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant
mortality to Ceriodaphnia dubia at an effluent concentration of 56% at 5.0 MGD flow and 66%at 7.5
MGD flow.
The permit holder shall perform at a minimum,quarterly monitoring using test procedures outlined in
the"North Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure," Revised December 2010, or
subsequent versions or"North Carolina Phase II Chronic Whole Effluent Toxicity Test Procedure"
(Revised-December 2010) or subsequent versions. The tests will be performed during the months of
March,June, September and December. These months signify the first month of each three-month
toxicity testing quarter assigned to the facility. Effluent sampling for this testing must be obtained
during representative effluent discharge and shall be performed at the NPDES permitted final effluent
discharge below all treatment processes.
If the test procedure performed as the first test of any single quarter results in a failure or ChV
below the permit limit,then multiple-concentration testing shall be performed at a minimum,in
each of the two following months as described in"North Carolina Phase II Chronic Whole Effluent
Toxicity Test Procedure" (Revised-December 2010) or subsequent versions.
All toxicity testing results required as part of this permit condition will be entered electronically using
the Divisions eDMR system for the month in which tests were performed,using the parameter code
TGP3B for the pass/fail results and THP3B for the Chronic Value. Additionally,DWR Form AT-3
(original) is to be sent to the following address:
Attention: North Carolina Division of Water Resources
Water Sciences Section/Aquatic Toxicology Branch
1621 Mail Service Center
Raleigh,NC 27699-1621
Or,results can be sent to the email, ATForms.ATB@ncdenr. ov.
Completed Aquatic Toxicity Test Forms shall be filed with the Water Sciences Section no later than 30
days after the end of the reporting period for which the report is made.
Test data shall be complete,accurate, include all supporting chemical/physical measure s-a&Ad at1:
concentration/response data, and be certified by laboratory supervisor and ORC or appr v �t ADKftbtVb
Page 6 of 13
Michael Montebello,NPDES Branch Chief
Modification Effective Date: August 5,2024