NC0048879_Draft Permit_20230815

ROY COOPER
Governor
ELIZABETH S.BISER
Secretary
RICHARD E.ROGERS,JR. NORTH CAROLINA
Director Environmental Quality
August 15, 2023
Mr. Jamie Revels, Utilities Director
Town of Cary
P.O. Box 8005
Cary,North Carolina 27512
Subject: Draft NPDES Permit Renewal
Permit NC0048879
North Cary WRF
Wake County
Grade IV Biological WPCS
SIC Code 4952
Dear Mr. Revels:
Enclosed with this letter is a copy of the Draft NPDES permit renewal for your facility. Please
review this draft carefully to ensure thorough understanding of the requirements and conditions it
contains. There are several changes from the existing permit, including the following:
• For clarity, the instream monitoring requirements have been relocated from Section
A.(1.) to Special Condition A.(2.) Instream Monitoring Requirements.
• Based on the 2002 Instream Fecal Coliform Monitoring Guidance, as the receiving
stream is classified as B waters, instream monitoring for fecal coliform has been added to the
permit [See Special Condition A.(2.)].
• Based on discussion with the Division's Basin Planning Branch and as the receiving
stream is classified as NSW waters, instream monitoring for TKN,NO2+NO3, and TP has
been added to the permit [See Special Condition A.(2.)].
• Total Residual Chlorine(TRC) limits and monitoring requirement have not been in the
permit, as the facility uses UV for disinfection. However, in the event of an emergency where
chlorination is required as a backup or temporary means of disinfection at the facility, a TRC
limit and monitoring requirement have been added to the permit. Please note that TRC
monitoring is only required when chlorine is used at the plant, and as part of the regular
Effluent Pollutant Scans.
• Based on Mercury TMDL evaluation reporting no mercury values reported at levels > 1
ng/L during the period reviewed, Special Condition A.(9.) Mercury Minimization Plan has
been removed from the permit.
• A special condition to monitor effluent PFAS chemicals quarterly has been added to the
permit, to be effective six (6) months after EPA has a final wastewater method in 40 CFR136
method published in the Federal Register. In the event that any new Significant Industrial
User(SIU) suspected of discharging PFAS compounds discharges to the North Cary WRF,
the monitoring frequency for PFAS chemicals shall be increased to monthly with the option
for the Town to request reduction of monitoring after 12 months of data collection and the
data are evaluated for presence and concentrations of PFAS chemicals [See Special
Condition A.(6.) PFAS Monitoring Requirements].
.forth ror ent of Environm Q I Dources
512 NoCarth SalisburylinaDepa Street I1611 Mail Serviental ce Centeruality I Raleighivision of,NorthWater CResazolina 2 7699-1 61 1
oN a fmo; ,tV ant � 919.707.9000

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• For consistency with permits subject to the Neuse River Nutrient Management Strategy,
some of the wording has changed in Special Condition A.(7.)Total Nitrogen Allocations
please review each paragraph carefully.
• As the condition merely reiterates the Division's practice, Special Condition A.(5.)
Clarification of Compliance When a Permit Limit is Set At or Below ML(Minimum Levels)
has been removed from the permit.
• Some of the wording has changed in Special Condition A.(3.), Chronic Toxicity Permit
Limit,please review each paragraph carefully.
• Special Condition A.(4.)has been modified to include the specific three years in which the
Effluent Pollutant Scan shall be performed(2025, 2026, and 2027). In addition, some of the
wording has changed in Special Condition A.(4.),please review each paragraph carefully.
• A notation was made concerning the Electronic Reporting Rule — NPDES Electronic
Reporting Rule — Phase 2 Extension. EPA extended the Phase 2 deadline to December 21,
2025.
The NPDES standard conditions(Parts II,III,and IV)that are a part of the permit are not included
in this draft document (cover, map, and Part I). The conditions are the same as in your current
permit except that agency and division names have been updated.The latest version is available at
https://bit.ly/3k5NFaL and can be viewed online or downloaded as a PDF file.
Concurrent with this notification the Division is publishing a notice in a newspaper having
circulation in the general Wake County area,soliciting public comments on this draft permit.
Please provide any written comments you may have to the following:NCDEQ/DWR,NPDES
Permitting Branch, 1617 Mail Service Center,Raleigh,NC 27699-1617 no later than 30 days
after receipt of this draft permit.
Following the 30-day public comment period,the Division will review all pertinent comments
and take appropriate action prior to issuing a final permit.If you have questions concerning this
draft permit,please call me at(919)707-3609 or by email at [e-mail].
Sincerely,
r—DocuSi n.d by:
%,-..-7900n4a8FCAUFD
Nick Coco,PE
NPDES Municipal Permitting Unit
Hardcopy: NPDES Files
Ecopy: US EPA Region 4
DWR/Raleigh Regional Office/Water Quality/Scott Vinson and Vanessa Manuel
DWR/Operator Certification Program/Maureen Kinney
DWR/Ecosystems Branch/Mark Vander Borgh
DWR/Aquatic Toxicology Branch/Cindy Moore and Molly Nicholson
DWR/Municipal Permitting Unit/Keyes McGee
LNBA/Executive Director/Haywood Phthisic
Town of Cary/F'acility Operations Supervisor/Jonathan Bulla
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' . 919 707.9000
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Permit NC0048879
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WATER RESOURCES
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
(NPDES)
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 Cary
is hereby authorized to discharge wastewater from a facility located at the
North Cary Water Reclamation Facility(WRF)
1900 Old Reedy Creek Road
Cary
Wake County
to receiving waters designated as an unnamed tributary to Crabtree Creek in the Neuse River Basin
in accordance with the effluent limitations,monitoring requirements.and other applicable conditions set
forth in Parts 1,1I,III,and IV hereof.
This permit shall become effective Month xx.20xx.
This permit and authorization to discharge shall expire at midnight on February 28,2028.
Signed this day Month xx,20xx.
DRAFT
for Richard E.Rogers,Jr.,Director
Division of Water Resources
By Authority of the Environmental Management
Commission
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Permit NC0048879
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility,whether for operation or discharge are hereby
revoked.As of this permit issuance,any previously issued permit bearing this number is no longer
effective. Therefore,the exclusive authority to operate and discharge from this facility arises under the
permit conditions,requirements, terms, and provisions included herein.
Town of Cary
is hereby authorized to:
1. Continue to operate and maintain the North Cary WRF,an existing 12.0 MOD facility consisting of
the following components:
• Mechanical screening
• Influent pump station
• Grit and grease removal system
• Nutrient removal system consisting of anaerobic selectors,oxidation ditches,anoxic zones and
reaeration zones
• Secondary clarifiers
• Deep-bed sand filters
• Ultraviolet disinfection
• Cascade aeration
• Belt thickeners
• Aerated holding tanks
2. Operate facilities for bulk and reclaimed water distribution in accordance with Non-Discharge Permit
WQ0017923.
3. Discharge from said treatment works at the location specified on the attached map via Outfall 001
into an unnamed tributary to Crabtree Creek,classified B;NSW waters in the Neuse River Basin and
03020201 HUC.
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Permit NC0048879
PART]
A.(1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS 112.0 MGD]
[15A NCAC 02B.0400 et seq.. 15A NCACO2B.0500 et seq.]Grade IV
Biological Water Pollution Control System[1SA NCAC 08G.0302]
(a.) During the period beginning on the effective date of the permit and lasting until permit expiration,
the permittee is authorized to discharge treated municipal and industrial 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 12.0 MOD Continuous Recording I or E
Total Monthly Flow(MG) 82220 Monitor and Report Monthly Calculated E
CBOD,5 clay,20°C 3
80082 4.1 mgil. 6.0 ngiL nveek° Composite 1 and E
(Apr 1-Oct 31)
CBOD.5 day.20°C 3 0 r . a
(Nov 1-Mar 31) 80082 8.2 luta 1.,t 3 init. 2/creek Composite I and E
Total Suspended Solids3 C0530 30.0 mgL 45.0 ng/L 2//week4 Composite I and E
NII3 as N(Apr 1-Oct 31) CO610 0.5 nug/L 1.5 mg'L 2/week 4 Composite E
Nth as N(Nov 1-Mar 31) C0610 1.0 mgil. 3.0 mg/L 2/week4 Composite E
Fecal Coliform 31616 200/100 nil. 400/100 mi. 2.-week 4 Grab E
(geometric mean)
Dissolved Oxygen 00300 Daily Average?5.0 ing:L Daily Grab E
pH 00400 Between 6.0 and 9.0 Standard Units Daily Grab E
Temperature(CC) 00010 Monitor and Report Daily Grab E
Total Residual Chlorine` 50060 12 pgL Daily Grab E
Total Phosphorus(mg/L) C0665 2.0 mg/L.(Quarterly Average)e Weekly Composite E
TEN(mg/'L) 00625 Monitor and Report Weekly Composite E
NO3-N+NO2-N(mgL) 00630 Monitor and Report Weekly Composite E
Total Nitrogen 7(mg/L) C0600 Monitor and Report Weekly Calculated i E
T V Load s s QM600 Monitor and Report(lb/month) Monthly Calculated E
Q1'600 143,246 lb/yr Annually
PEAS various Footnote 10 Footnote 10 Grab E
Chronic Toxicityuu TGP3B Monitor and Report Quarterly Composite E ry
Effluent Pollutant Scan 12 NCO/ Monitor and Report Footnote 12 Footnote 12 E
Hardness"-Total as CaCO3(tng/L) 00900 Monitor and Report Quarterly Composite E
Footnotes:
I. The permittee shall submit Discharge Monitoring Reports electronically using NC DWR's eDMR application
system. See Special Condition A.(10.).
2. Sample locations 1-Influent.E-Effluent.
3. The monthly average effluent 13U1)5 and Total Suspended Solids concentrations shall not exceed 15%of the
respective influent value(85%removal).
4. Twice per week sampling must occur on any two non-consecutive days during the calendar week.
5. The facility shall monitor TRC when using chlorination for disinfection.The Division shall consider all effluent
total residual chlorine values reported below 50 pgil 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 pg/l.
Footnotes continue on the next page.
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Permit NC0048879
Footnotes continued from A.(1.)Effluent Limitations and Monitoring Requirements:
6. The quarterly average for total phosphorus shall be the average of composite samples collected during each
calendar quarter(January-March,April-June,July-September,October-December).
7. 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 NOS N are Nitrate and Nitrite Nitrogen,respectively.
8. IN Load is the mass load of TN discharged by the permittee in a period of time.See Special Condition A.(5.).
9. Compliance with these limits shall be determined in accordance with Special Condition A.(6.),Annual Limits
for Total Nitrogen.
10. See Special Condition A.(9.).
11. Chronic Toxicity(Ceriodaphnia dubia)P/F at 90%with testing in February,May,August,and November.See
Special Condition A.(3.).
12. The permittee shall perform three effluent pollution scans during the term of this permit.See Special Condition
A.(4.).
13. Effluent hardness shall be performed in conjunction with testing for hardness dependent metals.
There shall be no discharge of floating solids or visible foam in other than trace amounts.
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Permit NC0048879
A.(2.) INSI'REAM MONITORING REQUIREMENTS
[15A NCAC 02B.0500 et seq.]
Beginning on the effective date of this permit and lasting until lasting until permit expiration,the
Permittee shall perform instream sampling upstream and downstream of Outfall 001 as specified below:
MONITORING REQUIREMENTS
PARAMETER
Parameter Code Measurement Sample Type Sample Location t
Frequency
CBOD;(tngtL) 80082 Variable' Grab U.Dt_a
NH3, as N( g )m •1 C0610 Variable' Grab U,Di-3
Dissolved Oxygen(mg'L) 00300 Variable' Grab U,Di.;
Fecal Goldoni)(t'l lxfntl) 31616 Variable' Grab U,Di-
(geometric mean)
pH(s.n.) 00400 Variable' Grab D2
Temperature(°C) 00010 Variable' Grab U.D1-3
TI{N(mil.) 00625 Monthly Grab U,D1.3
NO3-N T NOi-N(mg:I.) 00630 Monthly Grab U.D1.3
Total Nitrogen{mg'L) C0600 Monthly Grab U,D1.3
Total Phosphorus(mg%L) C0665 Monthly Grab U.Di.3
Hardness-Total as CaCO3(tng/L)2 00900 Quarterly Grab or
Footnotes:
1. Sample locations U-Upstream at Old Reedy Creek Road,Di—Downstream at Ebenezer Church Road,D2—
Downstream between U.S. 1 and Lassiter Mill Dam,D3—Downstream at New Hope Road.Upstream and
downstream samples shall be grab samples collected 3/week during June.July,August,and September and
I/week during the remainder of the year.Instream sampling requirements for are provisionally waived in light
of the permittee's participation in the Lower:Meuse River Basin Association(LNBA).Should participation in
the association cease,all instream sampling requirements are inunediately reinstated.Locations U and Di are
not monitored under the LNBA agreement with the Division.
2. The permittee shall sample instream hardness upstream of the facility's discharge.The sample shall be
representative of the hardness in the stream.If the permittee is a member of the Monitoring Coalition Program,
sampling for instream hardness may be waived as long as the Monitoring Coalition agrees to sample hardness at
the nearest upstream location,at a minimum frequency of quarterly.and the permittee has obtained approval
from DWR-NPDES Permitting Unit that the upstream station being monitored by the coalition is representative
of the receiving stream for this discharge.The permittee is responsible for submitting instream hardness test
results with its DMRs as results are received from the coalition,If coalition membership is cancelled or the
Monitoring Coalition terminates instream hardness sampling at the approved station,the permittee will
immediately notify the Division and resume sampling for instream hardness,upstream of its discharge,as
required in Section A.(2.),
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Permit NC0048879
A.(3.) CHRONIC TOXICITY PERMIT LIMIT(QUARTERLY)
[I5A NCAC 02B.0200] [15A NCAC 02B .0500 et seq]
The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant
mortality to Ceriodaphdia dubia at an effluent concentration of 90%.
The permit holder shall perform at a minimum,quarterly monitoring using test procedures outlined in
the"North Carolina C.eriodapimia 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
February,May,August,and November.These months signify the first month of each three-month
toxicity testing quarter assigned to the facility.Effluent sampling for this testing must be obtained during
representative effluent discharge and shall be performed at the NPDES permitted final effluent discharge
below all treatment processes.
If the test procedure performed as the first test of any single quarter results in a failure or ChV
below the permit limit,then multiple-concentration testing shall be performed at a minimum,in
each of the two following months as described in"North Carolina Phase II Chronic Whole Effluent
Toxicity Test Procedure"(Revised-December 2010,or subsequent versions).
All toxicity testing results required as part of this permit condition will be entered electronically using the
Division's eDMR system for the months in which tests were performed,using the parameter code
TGP3B for the pass/fail results and THP3B for the Chronic Value.Additionally,DWR Form AT-3
(original)is to be sent to the following address:
North Carolina Division of Water Resources
Water Sciences Section/Aquatic Toxicology Branch
1621 Mail Service Center
Raleigh,NC 27699-1621
Or,results can be sent to the email,ATForms.ATBdeq.nc.gov.
Completed Aquatic Toxicity Test Forms shall be filed with the Water Sciences Section no later than 30
days after the end of the reporting period for which the report is made.
Test data shall be complete,accurate,include all supporting chemical/physical measurements and all
concentration/response data,and be certified by laboratory supervisor and ORC or approved designate
signature.Total residual chlorine of the effluent toxicity sample must be measured and reported if
chlorine is employed for disinfection of the waste stream.
Should there be no discharge of flow from the facility during a month in which toxicity monitoring is
required,the permittee will complete the information located at the top of the aquatic toxicity(AT)test
form indicating the facility name,permit number,pipe number,county,and the month/year of the report
with the notation of"No Flow"in the comment area of the form.The report shall be submitted to the
Water Sciences Section at the address cited above.
Should the permittee fail to monitor during a month in which toxicity monitoring is required,monitoring
will be required during the following month.Assessment of toxicity compliance is based on the toxicity
testing quarter,which is the three-month time interval that begins on the first day of the month in which
toxicity testing is required by this permit and continues until the final day of the third month.
Should any test data from this monitoring requirement or tests performed by the North Carolina Division
of Water Resources indicate potential impacts to the receiving stream,this permit may be re-opened and
modified to include alternate monitoring requirements or limits.
NOTE:Failure to achieve test conditions as specified in the cited document,such as minimum control
organism survival,minimum control organism reproduction,and appropriate environmental controls,
shall constitute an invalid test and will require immediate follow-up testing to be completed no later than
the last day of the month following the month of the initial monitoring.
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Permit NC0048879
A.(4.) ADDITIONAL MONITORING REQUIREMENTS FOR PERMIT RENEWAL
[G.S. 143-215.1(B)]
(a.) Effluent Pollutant Scans. The pennittee shall perform a total of three(3)Effluent Pollutant Scans
for all parameters listed below.One scan must be performed in each of the following years: 2025.
2026,and 2027. Analytical methods shall be in accordance with 40 CFR Part 136 and shall be
sufficiently sensitive to determine whether parameters are present in concentrations greater than
applicable standards and criteria.Each annual sample shall coincide with one quarterly toxicity test
each year(see Condition A.(3.)(CHRONIC TOXICITY PERMIT LIMIT(QUARTERLY))),and
each must be collected in a different calendar quarter to represent seasonal variation[i.e.,do not
sample in the same quarter every year]. Unless otherwise indicated,metals shall be analyzed as
"total recoverable."
Ammonia(as N) C0610 Trans-l,2-dichloroethylene 34546 Bis(2-chloroethyl)ether 34273
Chlorine(total residual.TRC) 50060 1,l.dichloroethylene 34.501 Bis(2-chloraisoprapyl)ether 34283
Dissolved oxygen 00300 1,2-dichloropmpanc C0541 Bis(2-ethylhexyl)phthalate CO100
Nitrate!Nitrite 00630 1.3-dichlornpropylene 77163 4-bromophenyl phenyl ether 34636
Kjetdahl nitrogen 00625 Ethylbenzene 34371 Butyl benzyl phthalate 34292
Oil and grease 00556 Methyl bromide 34413 2-chloronaphthalene 34581
Phosphorus C0665 Methyl chloride 34418 4-clilanphenyl phenyl ether 34641
Total dissolved solids 70295 Methylene chloride 34423 Chrysene 34320
Hardness 00900 1,1.2,2-tetraehloroethane 81549 Di-n-butyl phthalate 39110
Antimony 01097 Tetraclilorocthylcne 34475 Di-n-octyl phthalate 34596
Arsenic 01002 Toluene 34040 Dibenzo(a.h)anthrecene 34556
Beryllium 01012 1,1.1-trichloroethane 34506 1.2-dichlorobenzene 34536
Cadmium 01027 1,1,2-trichloroethane 34511 1.3-dichlorobenzcnc 34566
Chromitun C0034 Trichloroethylene 39180 1.4-diehlorobenzenc 34571
Copper 01042 Vinyl chloride 39175 33-dichlorobenzidine 34631
Lead 01051 4cid-extractable compounds: Diethyl phthalate 34336
Mercury(Method 1631E) COMER P-chloro-m-eresol 34452 Dimethyl phthalate 34341
Nickel 01067 2-clilorophenol 34586 2.4-dinitrotohxne 34611
Seleniwn 01147 2.4-diehlorophenol 34601 2.6-dinitrotolueae C0626
Silver 01077 2,4-dimethylphenol 34606 1.2-diphenylhydrazine 34346
Thallium 01059 4.6-dinitro-o-cresol 34657 Fluorandhene C0376
Zinc 01092 2,4-dinitrophenol 34616 Fluohrne 34381
Cyanide 00720 2-nitrophenol 34591 Hexachlorobenzene C0700
Total phenolic compounds 32730 4-nitrophenol 34646 Hexachlorobutadiene C0702
Volatile oceanic compounds: Pentachlorophcnot 39032 Hexachlarocyclo-pentadienc 34386
Acrolein 34210 Phenol 34694 Hexachloroethane 34396
Acrylonitrile 34215 2.4,6-trichlorophenol 34621 Indeno(1.2,3-cd)pyrene 34403
Benzene 34030 Base-neutral compounds: Isophoronc 34408
Bromoform 32104 Acenaphthenc 34205 Naphthalene 34696
Carbon tetrachloride 32102 Acenaphthylene 34200 Nitrobenzene 34447
Chlorobenzene 34301 Anthr'acenc CO220 N-nitrosodi-n-propylaminc 34428
Chlorodibromomethanc 34306 Benzidine 39120 N-nitrosodimcthylamurc 34438
Chloroethanc 85811 Benzo(a)anthracene C0526 N-nitrosodiphenylamine 34433
2-chloroethyl vinyl ether 34576 Benzo(a)pymK 34247 Phenanthrene 34461
Chloroform 32106 3,4 benzofluorarrthene 34230 Pyrene 34469
Dichlorobromomet hane 32101 Benzo(ghi)peryleue 34521 1.2.4-trichlorobenzenc C0551
1.1-dichlornethane 34496 Benzo(k)fluoranthene 34242
1,2-dichloroethane 32103 Bis(2-chioroethoxy)methane 34278
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Permit NC0048879
(b.) Effluent Scan Reporting. Test results shall be reported electronically via eDMR by December
31st of each designated sampling year,except that,subject to prior written approval by the Director,
results can be reported on DWR Form DMR-PPA-1 or other form approved by the Director. The
permittee must at least report completion of the test in the eDMR system by entering"1"or"Y"for
parameter code NCO1 -Annual Pollutant Scan. If written reports are approved,the report shall be
submitted to the following address:
North Carolina Division of Water Resources
Central Files
1617 Mail Service Center
Raleigh,North Carolina 27699-1617
Or the form may be uploaded at:https://edocs.deq.nc.gov/Fonns/NPDES_WW-EDMR-
Supplemental-Form
(c.) 2'-Species Toxicity Testin¢and Reporting.
(i.) In addition to the quarterly toxicity tests required in Condition A.(3.)(CHRONIC TOXICITY
PERMIT LIMIT(QUARTERLY)),the Permittee shall perform and report the results of four
(4)toxicity tests using the same test methods using a second species of test organism suitable
to the tests being conducted.
(ii.) The 2°d species toxicity tests shall be conducted either:
(A) Once per quarter in a single 12-month period(four samples);if this option is chosen,
the sample for each 2nd species test shall coincide with the quarterly samples collected
for(CHRONIC TOXICITY PERMIT LIMIT(QUARTERLY));or
(13) Once per 12-month period in the four-and one-half year period prior to the scheduled
application for permit renewal(four samples):if this option is chosen,three of the
samples for the 2nd species test shall coincide with those for the annual effluent scans
and the coincident quarterly toxicity test,and each of the four annual samples shall be
collected in a different calendar quarter in order to represent seasonal variation.
(iii.) The results of the toxicity tests shall be submitted to the following address:
North Carolina Division of Water Resources
Water Sciences Section/Aquatic Toxicology Branch
1621 Mail Service Center
Raleigh,North Carolina 27699-1621
Or,results can be sent to the email,[e-mail].
(iv.) Results of the 2°d species tests shall also be summarized in Part E(Toxicity Testing Data)of
EPA Municipal Application Form 2A when submitting the permit renewal application to the
NPDES Wastewater Program.
The Permittee may contact the Division's Aquatic Toxicology Branch at 919-743-8401 for
guidance on conducting the additional toxicity tests and reporting of the results.
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Permit NC0048879
A.(5.) CALCULATION OF TOTAL NITROGEN LOADS
[G.S. 143-215.1(b)]
(a.) The Pennittee shall calculate monthly and annual TN Loads as follows:
(i.) Monthly TN Load(tb/mo)=TN x TMF x 8.34
where:
TN = the average Total Nitrogen concentration(mg/L)of the composite
samples collected during the month
TMF = the Total Monthly Flow of wastewater discharged during the month
(MG/mo)
8.34 = conversion factor,from(mgfL x MG)to pounds
(ii.) Annual TN Load(lb/yr)=Sum of the 12 Monthly TN Loads for the calendar year
(b.) The Permittee shall report monthly Total Nitrogen results(ntgtL and lb/mo)in the discharge
monitoring report for that month and shall report each year's annual results(lb/yr)in the December
report for that year.
A.(6.) ANNUAL LIMITS FOR TOTAL NITROGEN
[G.S. 143-215.1(b)]
(a.) Total Nitrogen(TN)allocations and TN Load limits for NPDES dischargers in the Neuse River
basin apply on a calendar year basis.
(b.) For any given calendar year,the pennittee shall be in compliance with the annual TN load limit in
this Permit if:
(i.) the permittee's annual TN discharge is less than or equal to its TN Load limit,or
(ii.) the permittee is a co-pennittee member of a compliance association.
(c.) If the permittee is not a co-permittee member of a compliance association and the permittee's
cumulative annual TN discharge exceeds the effective TN Load limit in this permit at any point
during the calendar year,the pennittee is in violation of its TN Load limit,and each day of a
continuing violation shall constitute a separate violation.
(d.) The TN Load limit in this Permit(if any)may be modified as the result of allowable changes in the
permittee's TN allocation.
(i.) Allowable changes include those resulting from purchase of TN allocation from the Wetlands
Restoration Fund;purchase,sale,trade,or lease of allocation between the permittee and other
dischargers;regionalization;and other transactions approved by the Division.
(ii.) The pennittee may request a modification of the TN Load limit in this Permit to reflect
allowable changes in its TN allocation.Upon receipt of timely and proper application,the
Division will modify the permit as appropriate and in accordance with state and federal
program requirements.
(iii.) Changes in TN limits become effective on January 1 of the year following permit
modification.The Division must receive application no later than August 31 for changes
proposed for the following calendar year.
(iv.) Application shall be sent to:
NCDWR/NPDES Wastewater Program
Attn:Neuse River Basin Coordinator
1617 Mail Service Center
Raleigh,NC 27699-1617
(e.) If the permittee is a member and co-permittee of an approved compliance association,its TN
discharge during that year is governed by that association's group NPDES permit and the TN limits
therein.
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Permit NC0048879
(i.) The permittee shall be considered a co-permittee Member for any given calendar year in
which it is identified as such in Appendix A of the association's group NPDES permit.
(ii.) Association roster(s)and members'TN allocations will be updated annually and in
accordance with state and federal program requirements.
(iii.) If the permittee intends to join or leave a compliance association,the Division must be
notified of the proposed action in accordance with the procedures defined in the association's
NPDES permit.
(A) Upon receipt of timely and proper notification,the Division will modify the pennit as
appropriate and in accordance with state and federal program requirements.
(B) Membership changes in a compliance association become effective on January 1 of the
year following modification of the association's permit.
(f.) The TN monitoring and reporting requirements in this Permit remain in effect until expiration of
this Permit and are not affected by the permittee's membership in a compliance association.
A.(7.) TOTAL NITROGEN ALLOCATIONS
[G.S. 143-215.1(b)]
(a.) The following table lists the Total Nitrogen(TN)allocations and offset credits assigned to,acquired
by,or transferred to or from the permittee in accordance with the Neuse River nutrient strategy
(15A NCAC 02B.0700)and the status of each as of permit issuance.These allocations are not
enforceable limits,nor do they supersede any TN limit(s)established elsewhere in this permit or in
the NPDES permit of a compliance association of which the permittee is a co-pernittee Member.
ALLOCATION/CREDITS
ALLOCATION! AMOUNT'
CREDITS TYPE SOURCE DATE STATUS
Estuary Discharge
ObiY4 (1b!yr)
Base Allocation Assigned by Rule 2 12/7/97:4/1iO3 67.579 135.158 Active
Supplemental Town of Morrisville.NC0050041 2,022 4.044 Active
Allocation —
Supplemental 2.022 4,044 Active
Town of Morrisville.NC0050938
Allocation —'
TOTAL 71,623 143,246 Active
Footnotes:
Transport Factor 50%.
2. Rule 15A NCAC 02B.0713(formerly 02B.0234) •
(b.) Any addition,deletion,or modification of the listed allocations and credits(other than
typographical errors)or any change in status of any of the listed allocations and credits(if the
facility has no TN Load limit,substitute"any change of allocation or credits to active status")shall
be considered a major modification of this permit and shall be subject to the public review process
afforded such modifications under state and federal rules.
A.(8.) CLARIFICATION OF MONITORING REQUIREMENTS
[15A NCAC 2B .0505(C)(4)]
In accordance with 15A NCAC 2B.0505(c)(4),stream sampling may be discontinued when flow
conditions or extreme weather conditions could result in injury or death of the person(s)collecting the
samples. In such cases,on each day that sampling is discontinued,written justification for the
discontinuance shall be specified in the monitoring report for the month in which the event occurred.
This provision also applies to influent and effluent sampling.
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A.(9.) PFAS MONITORING REQUIREMENT
[G.S. 143-215.1(b.)]
This reporting requirement for the per- and polyfluoroalkyl substances (PFAS)parameters listed under
Table 1 of the Final Method 1633 takes effect the first full calendar quarter following six(6)months after
EPA publishes a 40 CFR part 136 Final PFAS Method for wastewater in the Federal Register.Monitoring
will be at a quarterly frequency.
In the event that any new Significant Industrial User (SIU) suspected of discharging PFAS compounds
discharges to the WWTP,the monitoring frequency shall be increased to monthly with the option for the
Town to request reduction of monitoring after 12 months of data collection and the data are evaluated for
presence and concentrations of PFAS chemicals.
Find the current parameters listed under Table 1 of the 411' Draft Method 1633 Analysis of Per- and
Polyfluoroalkyl Substances(PFAS)in Aqueous,Solid,Biosolids,and Tissue Samples by LC-MS/MS at:
hts://www.epa,Rov/system/files/documents.!2022-
12/3rd%20Draft%20Method%201633%20December%202022%2012-20-22 508.pdf
A.(10.) ELECTRONIC REPORTING-DISCHARGE MONITORING REPORTS
[G.S. 143-215.1 (b)]
Federal regulations require electronic submittal of all discharge monitoring reports(DMRs)and program
reports.The final NPDES Electronic Reporting Rule was adopted and became effective on December 21,
2015.
NOTE: This special condition supplements or supersedes the following sections within Part II of this
permit(Standard Conditions for NPDES Permits):
• Section B.(11.) Signatory Requirements
• Section D.(2.) Reporting
• Section D.(6.) Records Retention
• Section E.(5.) Monitoring Reports
1. Reporting Requirements[Supersedes Section D.(2.)and Section E.(5.1(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 monthly electronically using eDMR. The eDMR system allows permitted facilities to enter
monitoring data and submit DMRs electronically using the internet. The eDMR system may be
accessed at:https://deq.nc.gov/about/divisions/water-resources/edmr.
If a permittee is unable to use the eDMR system due to a demonstrated hardship or due to the facility
being physically located in an area where less than 10 percent of the households have broadband
access,then a temporary waiver from the NPDES electronic reporting requirements may be granted
and discharge monitoring data may be submitted on paper DMR forms(MR 1, 1.1,2,3)or alternative
forms approved by the Director. Duplicate signed copies shall be submitted to the following address:
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NC DEQ/Division of Water Resources/Water Quality Permitting Section
ATTENTION: Central Files
1617 Mail Service Center
Raleigh,North Carolina 27699-1617
See"How to Request a Waiver from Electronic Reporting"section below.
Monitoring results obtained during the previous month(s)shall be summarized for each month and
reported via the eDMR system no later than the last calendar day of the month following the
completed reporting period. Regardless of the submission method,the first DMR is due on the last
day of the month following the issuance of the permit or in the case of a new facility,on the last day
of the month following the commencement of discharge.
Starting on December 21,2025,the permittee must electronically report the following compliance
monitoring data and reports,when applicable:
• Sewer Overflow/Bypass Event Reports;and
• 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 establisha website that will alsolink 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:hops://wwwvw.federalregister.gov/documents/2015/10/22/2015-
24954/national-pollutant-discharge-elimination-system-npdes-electronic-reporting-rule
Electronic submissions must start by the dates listed in the"Reporting Requirements"section above.
3. Row 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
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to the Division unless the permittee re-applies for and is granted a
shall be submitted electronically pp
new temporary electronic reporting waiver by the Division. Approved electronic reporting waivers
are not transferrable. Only permittees with an approved reporting waiver request may submit
monitoring data and reports on paper to the Division for the period that the approved reporting waiver
request is effective.
Information on eDMR and the application for a temporary electronic reporting waiver arc kxind on
the following web page:
http://deq.nc.gov/about/divisionslwater-resourcesledmr
4. Signatory Requirements(Supplements Section B.(11.)(b)and Supersedes Section B.(11.1
All eDMRs submitted to the permit issuing authority shall be signed by a person described in Part II,
Section B.(11.)(a)or by a duly authorized representative of that person as described in Part II,
Section B.(1 l.)(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:
ltttp:,ideq.nc.govlabouttdivisions/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:
cert fi,under penalty of lay ,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.Mil
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].
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Permit NC0048879
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latiwde. 35 50'16" Sul-Basin: 03-04-02 Location
loreitude. 78 46'57 8-D.sit HUC. 03020201
C1u cj•: Cary,N.C. -61.-
Stream Class. B-N5\'.
Reteivirc Stream: CraCtrea Craei. Town of Cary
North Wake County
Permitted Flow 12 OMGC
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