HomeMy WebLinkAboutNC0073539_Fact Sheet_20240222 DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-lCF1970B553A
NCDEQ/DWR/NPDES
EXPEDITED FACT SHEET - NPDES PERMIT RENEWAL
NPDES Permit NCO073539
Caroline Robinson/Compliance&Expedited Permitting Unit/caroline.robinson(kdeq.nc.gov/Jan 2024
FACILITY INFORMATION
Applicant/Facility Name Aqua North Carolina,Inc. (Joe Pearce and Robyn Lambeth)
Willowbrook Subdivision WWTP
Applicant Address 202 MacKenan Court, Cary,NC 27511
Facility Physical 12309 Ramah Creek Court,Huntersville,NC 28078
Address/Mailing Address
Permitted Flow(MGD) 0.048 MGD
Type of Waste 100%Domestic, < 1 MGD
Facility Class WW-2 County Mecklenburg
Permit Status Renewal Regional Office MRO
STREAM CHARACTERISTICS
Receiving Stream Ramah Creek Stream C
Classification
Stream Segment 13-17-4-4 Outfall Lat. 350 26' 38"N
7Q 10 - Summer(cfs) 0.075 Outfall Long. 800 49'09" W
7Q10 -Winter(cfs) 0.15 Drainage basin Yadkin-Pee Dee River Basin
30Q2 (cfs) 0.15 Subbasin 03-07-11
Average Flow(cfs) 1.5 HUC 030401050101
IWC (%) 49.80%(summer)/ 303(d)List No
33.16%(winter)
BASIC INFO FOR EXPEDITED PERMIT RENEWAL
Already present in permit;however,revised ammonia
limits,based on the IWC calculations and 2016 NH3
guidance document,will take effect on 1/l/2028. These
Does permit need Daily Max NH3 limits? revised limits include,a monthly summer limit of 2
mg/L,a daily summer limit of 10 mg/L, a monthly
winter limit of 5 mg/L, and a daily winter limit of 25
mg/L.
Does permit need TRC limits/footnote? No—Already present in permit.
Does permit have toxicity testing? No—not a complex wastestream
Does permit have any Special Conditions? No
Does permit have instream monitoring? Yes—U&D for Temperature and Dissolved Oxygen
New expiration date: Nov 30,2028
FACILITY SUMMARY
Aqua North Carolina,Inc. operates a wastewater treatment plant for an estimated 249 residents.
Willowbrook Subdivision WWTP is a minor 100%domestic facility(flow< 1 MGD)with a design
capacity and permitted wastewater discharge of 0.048 MGD. The original NPDES permit for this facility
was issued in September 1988. This facility utilizes the following treatment components:
• Bar screen
• Aeration basin
• Clarifier
• Tablet chlorination w/contact tank
Fact Sheet for Permit Renewal
Jan 2024-NPDES Permit NCO073539-Page 1
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
• Dechlorination
• Aerated sludge holding tank
• Continuous flow measurement
• Composite sampler
• Auxillary power back up w/automatic transfer switch
• Aerated flow equalization tank
RENEWAL SUMMARY
This renewal contains the following changes:
• Updated the Supplement to Permit Cover Sheet by adding the aerated flow equalization tank to the
treatment components section.
• Added revised ammonia limits,based on the IWC calculations and 2016 N-13 guidance document,
that will take effect on 1/l/2028. These revised limits include, a monthly summer limit of 2 mg/L, a
daily summer limit of 10 mg/L, a monthly winter limit of 5 mg/L, and a daily winter limit of 25
mg/L. This change is shown in the table in Part I.A. (1).
• Updated eDMR language for electronic data submission in Part I. A. (2).
• Regional Office staff approved the draft permit.
COMPLIANCE HISTORY
Willowbrook Subdivision WWTP has had no enforcements since July 2016. The facility has had no NOVs
or NODS since the last permit was issued in February 2019.Most recent inspection(November 2021)
showed the facility to be in compliance.
COMMENTS ON DRAFT PERMIT
• Joseph Pearce(Chief of Operations and Engineering,Aqua North Carolina,Inc.)commented on the
permit limit changes in the draft and requested a review of the previous and new IWC calculations,
the 2016 Guidance Documents, and Fact Sheet for the permit. All documents were attached to the
comment response that included the following summary: According to the historical compilation of
documents on laserfiche the ammonia summer and winter monthly average limits were 2.0 and 5.0
mg/L respectively in the 2003-2008 permit and then were changed to the current 11.0 mg/L
summer limit in the 2008-2013 permit; however,I can't find any information on why that change
occurred.We don't typically increase the limit due to antibacksliding policies that prohibit the
relaxation of effluent limitations in reissued permits. According to the IWC calculation included,
the current 7Q 10 winter and summer values, and the 2016 ammonia permitting guidance the limits
need to be 2.0 and 5.0 mg/L for ammonia summer and winter monthly average limits respectively.
As shown in the draft permit,DWR has agreed that the revised ammonia limits will take effect
l/l/2028 in order to help the facility make these new ammonia limits.
Fact Sheet for Permit Renewal
Jan 2024-NPDES Permit NCO073539-Page 2
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
IWC Calculations
Facility:Willowbrook Subdivision WWTP
Permit No.: NC0073539
Prepared By: Caroline Robinson
Enter Design Flow(MGD): 0.048 <= Permitted Flow if Different from Design
Enter s7Q10(cfs): 0.075
Enter w7Q10(cfs): 0.15
Total Residual Chlorine(TRC) Ammonia(Summer)
Daily Maximum Limit(ug/1) Monthly Average Limit(mg NH3-N/1)
Design Permitted Design Permitted
s7Q10(CFS) 0.075 € s7Q10 (CFS) 0.075
DESIGN FLOW(MGD) 0.048 DESIGN FLOW (MGD) 0.048
DESIGN FLOW(CFS) 0.0744 € DESIGN FLOW(CFS) 0.0744
STREAM STD(UG/L) 17.0 STREAM STD (MG/L) 1.0
Upstream Bkgd (ug/1) 0 Upstream Bkgd (mg/1) 0.22
IWC(%) 49.80 € IWC(%) 49.80
Allowable Conc. (ug/1) 34 Allowable Conc.(mg/1) 1.8
< 1 MGD Policy Applies
Ammonia(Winter)
Monthly Average Limit(mg NH3-N/1)
Design Permitted Design Permitted
Fecal Coliform w7Q10(CFS) 0.15
Monthly Average Limit: 200/100ml #VALUE! DESIGN FLOW(MGD) 0.048
(If DF>331; Monitor) DESIGN FLOW (CFS) 0.0744
(If DF<331; Limit) STREAM STD(MG/L) 1.8
Dilution Factor(DF) 2.01 s #VALUE! Upstream Bkgd (mg/1) 0.22
IWC(%) 33.16
Allowable Conc. (mg/1) 5.0
*213 .0404(c)Applies
Total Residual Chlorine
1. Cap Daily Max limit at 28 ug/I to protect for acute toxicity
Ammonia (as NH3-N)
1. If Allowable Conc>35 mg/I, Monitor Only
2. Monthly Avg limit x 3=Weekly Avg limit(Municipals)
3. Monthly Avg limit x 5= Daily Max limit(Non-Munis)
If the allowable ammonia concentration is>35 mg/L, no limit shall be imposed
•By Policy dischargers< 1 MGD get limits no lower than 2&4 due to BAT
• From 2B .0404(c)-Winter Limits can be no less stringent than 2 times the summer limits
Fecal Coliform
1. Monthly Avg limit x 2=400/100 ml =Weekly Avg limit(Municipals)=Daily Max limit(Non-Muni)
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
Permit Enforcement History by Permit
Permit: NC0073539 Facility: Willowbrook Subdivision WWTP Owner: Aqua North Carolina Inc
Region: Mooresville County: Mecklenburg
Penalty Remission Enforcement EMC Collection Has
Assessment Penalty Enforcement Request Conference Hearing Memo Sent Payment Case
Case Approved Amount Costs Damages Received Held Held To AGO Total Paid Balance Due Plan Closed
LM-1991-0006 10/04/91 $4,600.00 $487.97 $0.00 10/31/91 12/04/91 02/13/92 $0.00 $5,087.97 No 05/09/16
LM-1998-0057 11/30/98 $1,150.00 $357.63 07/19/99 $753.82 $0.00 No 06/18/99
LV-2000-0001 01/07/00 $250.00 $73.33 $323.33 $0.00 No 02/07/00
LM-2001-0028 03/05/02 $3,225.00 $490.35 $3,715.35 $0.00 No 04/12/02
PC-2016-0045 07/20/16 $500.00 $100.00 08/24/16 10/04/16 $600.00 $0.00 No 10/31/16
Total Cases: 5 $9,725.00 $1,509.28 $5,392.50 $5,087.97
Total Penalties: $11,234.28 Total Penalties after $10,480.47
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
MONITORING REPORT(MR)VIOLATIONS for: Report Date: 10/10/22 Page 1 of 3
Permit: NCO073539 MRS Betweel 2 - 2019 and10 - 2023 Region: % Violation Category:Limit Violation Program Category: NPDES WW
Facility Name:% Param Nam(% County: % Subbasin:% Violation Action:%
Major Minor: %
PERMIT: NCO073539 FACILITY: Aqua North Carolina Inc-Willowbrook Subdivision COUNTY: Mecklenburg REGION: Mooresville
WWTP
Limit Violation
MONITORING VIOLATION UNIT OF CALCULATED %
REPORT OUTFALL LOCATION PARAMETER DATE FREQUENCY MEASURE LIMIT VALUE Over VIOLATION TYPE VIOLATION ACTION
04-2020 001 Effluent Chlorine,Total Residual 04/23/20 2 X week ug/I 28 34 21.4 Daily Maximum No Action, BPJ
Exceeded
06-2020 001 Effluent Chlorine,Total Residual 06/25/20 2 X week ug/I 28 34 21.4 Daily Maximum No Action, BPJ
Exceeded
09-2020 001 Effluent Chlorine,Total Residual 09/03/20 2 X week ug/I 28 31 10.7 Daily Maximum No Action, BPJ
Exceeded
03-2021 001 Effluent Chlorine,Total Residual 03/15/21 2 X week ug/I 28 36 28.6 Daily Maximum No Action, BPJ
Exceeded
04-2021 001 Effluent Chlorine,Total Residual 04/28/21 2 X week ug/I 28 37 32.1 Daily Maximum No Action, BPJ
Exceeded
06-2021 001 Effluent Chlorine,Total Residual 06/23/21 2 X week ug/I 28 35 25 Daily Maximum No Action, BPJ
Exceeded
09-2021 001 Effluent Chlorine,Total Residual 09/08/21 2 X week ug/I 28 42 50 Daily Maximum No Action, BPJ
Exceeded
01-2022 001 Effluent Chlorine,Total Residual 01/20/22 2 X week ug/I 28 29 3.6 Daily Maximum No Action, BPJ
Exceeded
02-2022 001 Effluent Chlorine,Total Residual 02/28/22 2 X week ug/I 28 32 14.3 Daily Maximum No Action, BPJ
Exceeded
04-2022 001 Effluent Chlorine,Total Residual 04/19/22 2 X week ug/I 28 40 42.9 Daily Maximum No Action, BPJ
Exceeded
05-2022 001 Effluent Chlorine,Total Residual 05/31/22 2 Xweek ug/I 28 34 21.4 Daily Maximum No Action, BPJ
Exceeded
07-2022 001 Effluent Chlorine,Total Residual 07/07/22 2 X week ug/I 28 39 39.3 Daily Maximum No Action, BPJ
Exceeded
07-2022 001 Effluent Chlorine,Total Residual 07/12/22 2 X week ug/I 28 35 25 Daily Maximum No Action, BPJ
Exceeded
07-2022 001 Effluent Chlorine,Total Residual 07/26/22 2 X week ug/I 28 30 7.1 Daily Maximum No Action, BPJ
Exceeded
10-2022 001 Effluent Chlorine,Total Residual 10/20/22 2 X week ug/I 28 37 32.1 Daily Maximum No Action, BPJ
Exceeded
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
MONITORING REPORT(MR)VIOLATIONS for: Report Date: 10/10/22 Page 2 of 3
Permit: NCO073539 MRS Betweel 2 - 2019 and10 - 2023 Region: % Violation Category:Limit Violation Program Category: NPDES WW
Facility Name:% Param Nam(% County: % Subbasin:% Violation Action:%
Major Minor: %
PERMIT: NCO073539 FACILITY: Aqua North Carolina Inc-Willowbrook Subdivision COUNTY: Mecklenburg REGION: Mooresville
WWTP
Limit Violation
MONITORING VIOLATION UNIT OF CALCULATED %
REPORT OUTFALL LOCATION PARAMETER DATE FREQUENCY MEASURE LIMIT VALUE Over VIOLATION TYPE VIOLATION ACTION
11-2022 001 Effluent Chlorine,Total Residual 11/15/22 2 X week ug/I 28 38 35.7 Daily Maximum No Action, BPJ
Exceeded
12-2022 001 Effluent Chlorine,Total Residual 12/08/22 2 X week ug/I 28 35 25 Daily Maximum No Action, BPJ
Exceeded
12-2022 001 Effluent Chlorine,Total Residual 12/16/22 2 X week ug/I 28 33 17.9 Daily Maximum No Action, BPJ
Exceeded
01-2023 001 Effluent Chlorine,Total Residual 01/10/23 2 X week ug/I 28 33 17.9 Daily Maximum No Action, BPJ
Exceeded
01-2023 001 Effluent Chlorine,Total Residual 01/24/23 2 X week ug/I 28 37 32.1 Daily Maximum No Action, BPJ
Exceeded
01-2023 001 Effluent Chlorine,Total Residual 01/26/23 2 X week ug/I 28 33 17.9 Daily Maximum No Action, BPJ
Exceeded
02-2023 001 Effluent Chlorine,Total Residual 02/24/23 2 X week ug/I 28 32 14.3 Daily Maximum No Action, BPJ
Exceeded
03-2023 001 Effluent Chlorine,Total Residual 03/14/23 2 X week ug/I 28 38 35.7 Daily Maximum No Action, BPJ
Exceeded
03-2023 001 Effluent Chlorine,Total Residual 03/21/23 2 X week ug/I 28 33 17.9 Daily Maximum No Action, BPJ
Exceeded
03-2023 001 Effluent Chlorine,Total Residual 03/29/23 2 X week ug/I 28 32 14.3 Daily Maximum No Action, BPJ
Exceeded
04-2023 001 Effluent Chlorine,Total Residual 04/13/23 2 X week ug/I 28 36 28.6 Daily Maximum No Action, BPJ
Exceeded
05-2023 001 Effluent Chlorine,Total Residual 05/09/23 2 X week ug/I 28 39 39.3 Daily Maximum No Action, BPJ
Exceeded
05-2023 001 Effluent Chlorine,Total Residual 05/17/23 2 X week ug/I 28 32 14.3 Daily Maximum No Action, BPJ
Exceeded
05-2023 001 Effluent Chlorine,Total Residual 05/18/23 2 X week ug/I 28 43 53.6 Daily Maximum No Action, BPJ
Exceeded
05-2023 001 Effluent Chlorine,Total Residual 05/23/23 2 X week ug/I 28 48 71.4 Daily Maximum No Action, BPJ
Exceeded
05-2023 001 Effluent Chlorine,Total Residual 05/31/23 2 Xweek ug/I 28 48 71.4 Daily Maximum No Action, BPJ
Exceeded
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
MONITORING REPORT(MR)VIOLATIONS for: Report Date: 10/10/22 Page 3 of 3
Permit: NCO073539 MRS Betweel 2 - 2019 and10 - 2023 Region: % Violation Category:Limit Violation Program Category: NPDES WW
Facility Name:% Param Nam(% County: % Subbasin:% Violation Action:%
Major Minor: %
PERMIT: NCO073539 FACILITY: Aqua North Carolina Inc-Willowbrook Subdivision COUNTY: Mecklenburg REGION: Mooresville
WWTP
Limit Violation
MONITORING VIOLATION UNIT OF CALCULATED %
REPORT OUTFALL LOCATION PARAMETER DATE FREQUENCY MEASURE LIMIT VALUE Over VIOLATION TYPE VIOLATION ACTION
06-2023 001 Effluent Chlorine,Total Residual 06/15/23 2 X week ug/I 28 33 17.9 Daily Maximum No Action, BPJ
Exceeded
06-2023 001 Effluent Chlorine,Total Residual 06/27/23 2 X week ug/I 28 43 53.6 Daily Maximum No Action, BPJ
Exceeded
07-2023 001 Effluent Chlorine,Total Residual 07/05/23 2 X week ug/I 28 49 75 Daily Maximum No Action, BPJ
Exceeded
07-2023 001 Effluent Chlorine,Total Residual 07/06/23 2 X week ug/I 28 33 17.9 Daily Maximum No Action, BPJ
Exceeded
07-2023 001 Effluent Chlorine,Total Residual 07/20/23 2 X week ug/I 28 43 53.6 Daily Maximum No Action, BPJ
Exceeded
07-2023 001 Effluent Chlorine,Total Residual 07/24/23 2 X week ug/I 28 31 10.7 Daily Maximum No Action, BPJ
Exceeded
07-2023 001 Effluent Chlorine,Total Residual 07/25/23 2 X week ug/I 28 32 14.3 Daily Maximum No Action, BPJ
Exceeded
08-2023 001 Effluent Chlorine,Total Residual 08/08/23 2 X week ug/I 28 37 32.1 Daily Maximum No Action, BPJ
Exceeded
08-2023 001 Effluent Chlorine,Total Residual 08/23/23 2 X week ug/I 28 38 35.7 Daily Maximum No Action, BPJ
Exceeded
08-2023 001 Effluent Chlorine,Total Residual 08/29/23 2 X week ug/I 28 33 17.9 Daily Maximum No Action, BPJ
Exceeded
08-2023 001 Effluent Chlorine,Total Residual 08/31/23 2 X week ug/I 28 36 28.6 Daily Maximum No Action, BPJ
Exceeded
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
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AFFIDAVIT OF PUBLICATION
Account# Order Number Identification Order Po Amount Cols Depth
28386 482734 Print Legal Ad-IPL01451280-IPLO145128 $644.38 2 26 L
Attention: Wren Thedford North Carolina } Ss
NCDENR/DWO/POINT SOURCE Mecklenburg County }
1617 MAIL SERVICE CENTER Before the undersigned,a Notary Public of said
RALEIGH,NC 276991671 County and State,duly authorized to administer
wren.thedford@ncdenr.gov oaths affirmations,etc.,personally appeared,
being duly sworn or affirmed according to law,
----------------------------------------------------------------------------
Public Notice cloth depose and say that he/she is a
North Carolina Environmental Management Commission/NPDES Unit representative of The Charlotte Observer
1617 Mail Service Center Publishing Company,a corporation organized and
Raleigh,NC 27699-1617 doing business under the laws of the State of
Notice of Intent to Issue a NPDES Wastewater Permit NCO073539 Willowbrook Delaware,and publishing a newspaper known as
Subdivision WWTP The North Carolina Environmental Management Commission
proposes to issue a NPDES wastewater discharge permit to the person(s)listed The Charlotte Observer in the city of Charlotte,
below. Written comments regarding the proposed permit will be accepted until County of Mecklenburg,and State of North
30 days after the publish date of this notice.The Director of the NC Division of y
Water Resources(DWR)may hold a public hearing should there be a significant Carolina and that as such he/she is familiar with
degree of public interest.Please mail comments and/or information requests to
DWR at the above address.Interested persons may visit the DWR at 512 N.Salis- the books,records,files,and business of said
bury Street,Raleigh,NC 27604 to review the information on file. Additional infor-
mation on NPD Ord y
ES permits and this notice may be found on our website:https:// p
deq.nc.gov/public-notices-hearings,or by calling (919)707-3601. Aqua North publication,the attached advertisement was
Carolina,Inc.applied to renew NPDES permit NCO073539 for the Willowbrook
Subdivision WWTP (12309 Ramah Creek Court, Huntersville) in Mecklenburg inserted.The following is correctly copied from
County.This facility discharges to Ramah Creek in the Yadkin-Pee Dee River the books and files of the aforesaid Corporation
Basin.Currently biochemical oxygen demand (BOD),ammonia nitrogen,dis- p
solved oxygen,fecal coliform,and total residual chlorine(rRC)are water quality and Publication.
limited.This discharge may affect future wasteload allocations in this portion of
Ramah Creek.
IPLO145128 1 insertion(s)published on:
Oct 25 2023 10/25/23
f
In Testimony Whereof I have hereunto set my hand
and affixed my seal on the 25th day of October,2023
Notary Public in and for the state of Texas,residing in
Dallas County
�'`' "'• STEPHANIEHIATCHER
jt
= ,- ;
x: •- My Notary ID#1335YAOO
Fjorss January 14,2026
Extra charge for lost or duplicate affidavits.
Legal document please do not destroy!
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
From: Bell.Wes
To: Pitner,Andrew
Cc: Robinson.Caroline
Subject: RE: Draft Permit Review NCO073539
Date: Thursday,October 12,2023 3:57:17 PM
Attachments: imaoe002.ona
imaae003,ona
Good afternoon Caroline,
Permit looks good to me!
Wes
Wes Bell
Env. Specialist II
Mooresville Regional Office
Water Quality Regional Operations Section
NCDEQ-Division of Water Resources
(704) 663-1699 Office
(704) 235-2192 Office Direct Line
Email: wes.bell Pdeq.nc.gov
610 East Center Avenue
Suite 301
Mooresville, NC 28115
NORTH CAROLINn
Department of Environmental Quality
Email correspondence to and from this address is subject to the North
Carolina Public Records Law and may be disclosed to third parties.
From: Pitner, Andrew<andrew.pitner@deq.nc.gov>
Sent:Thursday, October 12, 2023 3:30 PM
To: Bell, Wes<wes.bell@deq.nc.gov>
Cc: Robinson, Caroline<caroline.robinson@deq.nc.gov>
Subject: FW: Draft Permit Review NCO073539
Hey Wes,
Please review for MRO and respond to Caroline with any comments. Thanks,
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
Andrew
Andrew Pitner, P.G. -Andrew.Pitner(a)ncdenr.gov
Division of Water Resources - Water Quality Regional Operations
Mooresville Regional Office (MRO)
North Carolina Department of Environment& Natural Resources
610 East Center Avenue, Suite 301, Mooresville, NC 28115
MRO Main Phone: (704) 663-1699
Direct Office Phone: (704) 235-2180
MRO Fax: (704) 663-6040
DWR website: http://www.ncwater.org
NOTICE: Email correspondence to and from this address is subject to the North Carolina Public Records
Law and may be disclosed to third parties unless the content is exempt by statute or other regulation.
From: Robinson, Caroline<caroline.robinsonPdeq.nc.gov>
Sent:Thursday, October 12, 2023 2:56 PM
To: Pitner, Andrew<andrew.pitner(@deq.nc.g_ov>;Talbott,Jeffrey<ieffrey.talbott(@deq.nc.gov>
Cc: Scheller, Roberto<roberto.scheller(@deq.nc.gov>
Subject: Draft Permit Review NCO073539
Hi Andrew and Jeffrey,
The NCO073539 draft permit renewal is ready for review! The draft permit renewal for Willowbrook
Subdivision WWTP (NC0073539) will go to Notice on 10/24/2023. Please send me any comments as
time permits.
Thanks,
Caroline
Caroline Robinson (she/her/hers)
Environmental Specialist ll, Division of Water Resources
North Carolina Department of Environmental Quality
Office: (919) 707-9130 / Cell: (757)818-3696
caroline.robinson(@deq.nc.gov
NORTH CAROLINA -
Department of Environmental Quality
Email correspondence to and from this address is subject to the North
Carolina Public Records Law and may be disclosed to third parties.
Email correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to third
parties by an authorized state official.
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
From: Robinson,Caroline
To: Pearce,Joseph R
Cc: Watkins,Deborah M; Becker,Shannon V
Subject: RE: [External]RE: Draft NPDES permit NCO073539
Date: Tuesday,December 19,2023 12:19:00 PM
Attachments: IWC Calculations 73539.Ddf
imaae005.Dna
imaae006.Dna
image007.Dng
imaae008.Dna
imaae009.Dna
NCO073539 Draft FactSheet 2023.Ddf
Ammonia Permitting Guidance 2016.Ddf
NCO073539 Draft Permit 2023.Ddf
Hi Joe,
I am working on finalizing this permit for signature and I noticed that although I thought Charles
Weaver responded to this email, he did not include the attachments you asked for! We don't
typically do in person file reviews since all of the documents can be found online through Laserfiche,
NCO073539 or through the attachments I included with this email. According to the historical
compilation of documents (found at the previous link) the ammonia summer and winter monthly
average limits were 2.0 and 5.0 mg/L respectively in the 2003-2008 permit and then were changed
to the current 11.0 mg/L summer limit in the 2008-2013 permit; however, I can't find any
information on why that change occurred. We don't typically increase the limit due to anti-
backsliding policies that prohibit the relaxation of effluent limitations in reissued permits. According
to the IWC calculation included, the current 7Q10 winter and summer values, and the 2016
ammonia permitting guidance the limits need to be 2.0 and 5.0 mg/L for ammonia summer and
winter monthly average limits respectively. As shown in the draft permit, DWR has agreed that the
revised ammonia limits will take effect 1/1/2028 in order to help the facility make these new
ammonia limits.
Please let me know if you have any questions or concerns and again sorry for my delayed response.
Thanks,
Caroline
Caroline Robinson (she/her/hers)
Environmental Specialist ll, Division of Water Resources
North Carolina Department of Environmental Quality
Office: (919) 707-9130 / Cell: (757)818-3696
caroline.robinsonC@deq.nc.g_ov
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
ki ;NORTH CAROLINA �EQ
Department of Environmental Quality
Email correspondence to and from this address is subject to the North
Carolina Public Records Law and may be disclosed to third parties.
From: Pearce,Joseph R<JRPearce@aquaamerica.com>
Sent:Tuesday, October 31, 2023 12:05 PM
To: Robinson, Caroline<caroline.robinson@deq.nc.gov>
Cc: Watkins, Deborah M <DMWatkins@essential.co>; Becker, Shannon V
<SVBecker@aquaamerica.com>
Subject: [External] RE: Draft NPDES permit NCO073539
CAUTION: External email. Do not click links or open attachments unless verified. Report suspicious emails with the
Report Message button located on your Outlook menu bar on the Home tab.
Good Morning Ms. Robinson,
We have received the draft permit, NC0073359. Typically, with permit limit changes we are given
the opportunity to review the proposed changes prior to public notice. To my knowledge, we were
not provided that opportunity with this permit. I am requesting to review the previous and new IWC
calculations,the 2016 Guidance Documents, and the Fact Sheet for this permit. Was a new 70.10
established? I can be reached by cellphone at (919)605-6991 to schedule a file review in the
Archdale building.
Thank you,
Joe
AOUAII
Joseph Pearce PE CFM
Chief of Operations and Engineering
Aqua North Carolina,Inc.
202 MacKenan Court
Cary,North Carolina 27511
0: 919.653.6964 F:919.460.1788
coo
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
PAT MCCRORY
Governor
DONALD R. VAN DER VAART
secremry
Water Resources
ENVIRONMENTAL QUALITY S. JAY ZIMMEi RMAN
Director
Memorandum
To: NPDES Complex Unit
From: Tom Belnick
Date: July 20, 2016
Subject: NPDES Permitting Guidance
NPDES Implementation of Ammonia Criteria-Update
NC has still not adopted an ammonia standard, though it is on our WQS Triennial List for next
round. NC did establish ammonia chronic criteria for use in NPDES permitting back in 1989/90,
which was based on EPA's 1986 criteria development document that factored in pH/Temp across
three regions of the State (see attached). This evaluation resulted in ammonia chronic criteria of
1.0 mg/l NH3-N (summer) and 1.8 mg/l NH3-N (winter) for use in permitting purposes. NC
implements these chronic criteria as Monthly Averages limits utilizing instream dilution. In
2002,NC developed procedures for complimentary acute permit limits (discussed below).
The current ammonia permitting procedures should be as follows:
• The NH3/TRC Wasteload Allocation(WLA) spreadsheet automatically calculates
appropriate ammonia Monthly Average limits for summer and winter. The spreadsheet
assumes a background ammonia concentration of 0.22 mg/1.
• For any permit (new/renewal), always run the NH3/TRC WLA spreadsheet to verify
appropriate Monthly Average Ammonia Limits for protection of aquatic life.
• If the allowable ammonia concentration is greater than 35 mg/l,no limit should be
imposed.
• If the allowable concentration is less than 35 mg/1,then the allowable limit is needed and
the spreadsheet will automatically calculate it.
• For Municipal facilities,the acute limit will be expressed as a Weekly Average, and is
based on multiplying the Monthly Average limit by a factor of 3.
• For non-Municipal facilities,the acute limit will be expressed as a Daily Maximum, and
is based on multiplying the Monthly Average limit by a factor of 5.
• If a new more stringent ammonia limit is required, discuss the need for a Compliance
Schedule with senior staff and then with the Permitee.
• There is no RPA procedure used for ammonia; it is implemented strictly based on WLA
spreadsheet results (similar to TRC).
State of North Carolina I Environmental Quality I Water Resources
1617 Mail Service Center I Raleigh,North Carolina 27699-1617
919 707 9000
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
Page 12
• A sample NH3/TRC WLA is attached. In this example, the spreadsheet indicates that
Monthly Average ammonia limits of 3.2 mg/1 and 12.7 mg/1 should be imposed for
summer and winter, respectively, in order to protect for NC's chronic ammonia criteria.
Some additional considerations:
• This guidance will need to be revisited after NC formally adopts an ammonia standard for
both chronic and acute aquatic life protection.
• In the past, some ammonia limits were based strictly on protection of our DO standard
rather than ammonia toxicity, and that is why the permit writer should always verify the
correct ammonia limit with any permit renewal using the WLA spreadsheet.
• In the past, some practices allowed for maintaining a less stringent ammonia limit if the
facility was consistently passing the WET test(i.e., biology trumps chemistry). This is
no longer a valid approach and EPA would object. In April 2016 EPA expressly stated
that NC cannot use biology to override chemical results. EPA also disallowed the use of
Action Levels in permitting, in which toxicity test results (if passing) were used to
override the need for permit limits for copper/zinc/silver/iron/chloride.
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
i
_ ' • AMMONxA CRXTERTA TABLES (NH3 as N)
Based on EPA recommended 4-day maximum average concent.ration criteria
- r
j - Mountains and Trout 'Wdters
I
EMPE URE
H °C 2 C
6.8 025 0 31 U xo ed o, at
7. 0. 5 mg/01 s
TEMPERATURE
H 12°C 23°C .
6.8 1.8084 1.0028 Total Ammonia
7.5 1•.8084 1.0111 (mg/l NH3 as N)
<`- (:Piddmont Freshwaters
T MPE TUFF 5
fi °C r F 26° Af
� �0136 b.:00A4 n=xor�`' � u�ed' oni�
7. 0. 44 ..,.`� :01`4 .:; � /1 xNH3 as )
4 = d ,,
TEMPERATURE
H 14°C 260C
6.8 1.8084 1.1344 Total Ammonia
7.5 1.8084 1.1541 (mg/1 NH3 as N)
'r
Coastal Plain and Sandhills Freshwaters '
f
T MP r RA�tPU
{ •- H 1C 8°
i W5W
0. 0V 0 0 4 (Aftlm
ri414�
o��ia
6 0.'02 gV d �a
TEMPERATURE
H 160C 28°C
6.8 1.7920 0.9700 Total Ammonia
7.5 1.7920 0.9864 (mg/1 •NH3 as N)
• r
UV E
Somal
10/19/89
} ` t®0
DocuSign Envelope ID:2D58E04C-202E-44FB-9FFC-1CF1970B553A
NH3/TRC WLA Calculations
Facility: Anywhere USA
NC00
Prepared By: Tom Belnick
Enter Design Flow(MGD): 0.03
Enter s7Q10 (cfs): 0.13
Enter w7Q10 (cfs): 0.32
Total Residual Chlorine(TRC) Ammonia (Summer)
Daily Maximum Limit(ug/1) Monthly Average Limit(mg NH3-N/1)
s7Q10 (CFS) 0.13 s7Q10 (CFS) 0.13
DESIGN FLOW(MGD) 0.03 DESIGN FLOW(MGD) 0.03
DESIGN FLOW(CFS) 0.0465 DESIGN FLOW(CFS) 0.0465
STREAM STD (UG/L) 17.0 STREAM STD (MG/L) 1.0
Upstream Bkgd (ug/1) 0 Upstream Bkgd (mg/1) 0.22
IWC (%) 26.35 IWC (%) 26.35
Allowable Cone. (ug/1) 65 Allowable Cone. (mg/1) 3.2
Ammonia (Winter)
Monthly Average Limit(mg NH3-N/1)
Fecal Coliform w7Q10 (CFS) 0.32
Monthly Average Limit: 200/100mi DESIGN FLOW(MGD) 0.03
(If DF >331; Monitor) DESIGN FLOW(CFS) 0.0465
(If DF<331; Limit) STREAM STD (MG/L) 1.8
Dilution Factor(DF) 3.80 Upstream Bkgd (mg/1) 0.22
IWC (%) 12.69
Allowable Cone. (mg/1) 12.7
Total Residual Chlorine
1. Cap Daily Max limit at 28 ug/I to protect for acute toxicity
Ammonia (as NH3-N)
1. If Allowable Conc> 35 mg/l, Monitor Only
2. Monthly Avg limit x 3 = Weekly Avg limit(Municipals); capped at 35 mg/I
3. Monthly Avg limit x 5 = Daily Max limit(Non-Munis); capped at 35 mg/I
Fecal Coliform
1. Monthly Avg limit x 2 =400/100 ml= Weekly Avg limit(Municipals) = Daily Max limit(Non-Muni)
From: Lambeth,Robyn E
To: Robinson.Caroline
Cc: Pearce,Joseph R
Subject: RE: [EXTERNAL]NPDES Permit Issuance NCO073539
Date: Wednesday,February 28,2024 9:13:25 AM
Attachments: imaae001.ona
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Hi Caroline,
The Willowbrook permit has been received.
Robyn
From: Robinson, Caroline<caroline.robinson@deq.nc.gov>
Sent:Tuesday, February 27, 2024 3:51 PM
To: Lambeth, Robyn E<relambeth@aquaamerica.com>; Pearce,Joseph R
<jrpearce@aquaamerica.com>
Subject: [EXTERNAL] NPDES Permit Issuance NCO073539
CAUTION:This email originated from outside of the organization. Do not click links or open attachments unless you
recognize the sender and know the content is safe.
Good Afternoon!
I've attached a PDF of the permit issuance and fact sheet for NCO073539 /Willowbrook
Subdivision WWTP. Please respond to this email to confirm you have downloaded a copy for
your records.
Let me know if you have any questions or if you need a hard copy of the permit mailed to
you!
Thanks,
Caroline
Caroline Robinson (she/her/hers)
Environmental Specialist 11, Division of Water Resources
North Carolina Department of Environmental Quality
Office: (919) 707-9130 / Cell: (757)818-3696
caroline.robinson(@deq.nc.gov
NORTH CAROLINA
E Q
Department of Environmental Quality
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