NC0039420_Fact Sheet_20240603

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0
NCDEQ / DWR / NPDES
EXPEDITED FACT SHEET - NPDES PERMIT RENEWAL
NPDES Permit NCO039420
Caroline Robinson / Compliance & Expedited Permitting Unit / caroline.robinsongdeq.nc. og_v / March 2024
FACILITY INFORMATION
Applicant/Facility Name
Virginia Department of Transportation (Allen Campbell, State
Program Manager)
I-77 Rest Area WWTP
Applicant Address/Facility
Physical Address
Interstate Highway 77 NB on the NC / VA state line, Surry County, NC
27024
Mailing Address
1401 East Broad Street, Richmond, VA 23219
Permitted Flow (MGD)
0.02 MGD
Type of Waste
100% Domestic, < 1 MGD
Facility Class
WW-2
County
Surry
Permit Status
Renewal
Regional Office
WSRO
STREAM CHARACTERISTICS
Receiving Stream
Naked Run
Stream
Classification
WS-IV; Tr
Stream Segment
12-72-9-2
Outfall Lat.
360 33' 36" N
7Q10 - Summer (cfs)
02
Outfall Long.
800 44' 39" W
7Q10 - Winter (cfs)
0.39
Drainage basin
Yadkin -Pee Dee Basin
30Q2 (cfs)
0.4
Subbasin
03-07-03
Average Flow (cfs)
1.6
HUC
030401010804
IWC (%)
13.42% (summer) /
7.36% (winter)
303(d) List
No
BASIC INFO FOR EXPEDITED PERMIT RENEWAL
Does permit need Daily Max NH3 limits?
Due to regulation 2B .0404(c) the winter ammonia limit
can be no less stringent than 2 times the summer limits.
Therefore, the winter ammonia limit was changed to
12.0 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?
Yes — Nutrient Reopener for High Rock Lake
Does permit have instream monitoring?
Yes — U & D for Temp due to Trout Waters
New expiration date:
Feb 28, 2029
FACILITY SUMMARY
The Virginia Department of Transportation operates a 100% domestic wastewater treatment plant for an
estimated 2,000-5,000 traveling peoples per day with an estimated peak of 8,500 people a day. The I-77
Rest Area WWTP is a minor facility (flow < 1 MGD) with a design capacity and permitted wastewater
discharge of 0.02 MGD. The NPDES permit for this WWTP was originally issued in December 1977. This
facility utilizes the following treatment components:
• Grinder & basket
• Aerated equalization basin (ca. 14,000-gallon capacity)
• Soda ash feed
• Flow splitter box
• Three extended aeration package plants rated for 10,000 gallon each. Each plant includes:
Fact Sheet for Permit Renewal
March 2024 - NPDES Permit NC0039420 - Page 1

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0
• Aeration basin
• Secondary clarifier
• Sludge holding basin
• UV disinfection system
• Backup chlorine disinfection system with dechlorination
• Post aeration
• Ultrasonic flow meter
RENEWAL SUMMARY
This renewal contains the following changes:
• Added revised monthly average winter ammonia limit, based on the instream waste concentration
calculations and 2016 NH3 guidance document. The revised limit includes a monthly winter limit
of 12.0 mg/L. This change is shown in the table in Part L A. (1).
• Added effluent monitoring for turbidity to the table in Section A. (1.) to determine compliance with
15A NCAC 02B.0211 (21) for Trout waters.
• Added effluent monitoring for dissolved oxygen to the table in Section A. (1.) to determine
compliance with 15A NCAC 02B.0211 (6) for Trout waters.
• Updated Section A. (3) to reflect current federal requirements for Electronic Reporting of
Discharge Monitoring Reports.
• Public Water Supply Section staff approved the draft permit.
• Operator Certification Program staff approved the draft permit.
COMPLIANCE HISTORY
I-77 Rest Area WWTP has not had an enforcement on record since October 2009. The facility has been
issued one NOD for a BOD limit violation in 2022, since the permit was issued in March 2019. Most recent
inspection (April 2019) showed the facility to be in compliance.
COMMENTS ON DRAFT PERMIT
Ben Kirby (Winston-Salem Regional Office, Public Water Supply Section) noted that the Public
Water Supply Section concurs with the issuance of this permit provided the facility is operated and
maintained properly, the stated effluent limits are met prior to discharge, and the discharge does not
contravene the designated water quality standards.
Jeffrey Talbott (NC Operator Certification Program) noted "Operator certification notes that this
facility is classified as a Bio/WW-2, with the ORC and all Backup ORC's active and in good
standing with the program. We have no comments at this time."
Southern Environmental Law Center (SELC) sent a standard comment letter requesting a
temperature limit for this trout water discharge. NPDES management determined that effluent from
100% domestic WWTPs is not a heated liquid, as specified in Rule 15A NCAC 02B.0211, as
treatment occurs at ambient temperature with no artificial heating. No limit was added.
Fact Sheet for Permit Renewal
March 2024 - NPDES Permit NCO039420 - Page 2

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0
IWC Calculations
Facility: 1-77 Rest Area WWTP
Permit No.: NC0039420
Prepared By : Caroline Robinson
Enter Design Flow (MGD): 0.02 <= Permitted Flow if Different from Design
Enter s7Q10 (cfs): 0.2
Enter w7Q10 (cfs): 0.39
Total Residual Chlorine (TRC)
Ammonia (Summer)
Daily Maximum Limit (ug/1)
Monthly Average Limit (mg NH3-N/1)
Design Permitted
Design Permitted
s7Q10 (CFS)
0.2
s7Q10 (CFS)
0.2
DESIGN FLOW (MGD)
0.02
DESIGN FLOW (MGD)
0.02
DESIGN FLOW (CFS)
0.031
DESIGN FLOW (CFS)
0.031
STREAM STD (UG/L)
17.0
STREAM STD (MG/L)
1.0
Upstream Bkgd (ug/1)
0
Upstream Bkgd (mg/1)
0.22
IWC (%)
13.42
IWC (%)
13.42
Allowable Conc. (ug/1)
127
Allowable Conc. (mg/1)
6.0
Ammonia (Winter)
Monthly Average Limit (mg NH3-N/1)
Design Permitted
Design Permitted
Fecal Coliform
w7Q10 (CFS)
0.39
Monthly Average Limit:
200/100ml #VALUE!
DESIGN FLOW (MGD)
0.02
(If DF >331; Monitor)
DESIGN FLOW (CFS)
0.031
(If DF<331; Limit)
STREAM STD (MG/L)
1.8
Dilution Factor (DF)
7.45 #VALUE!
Upstream Bkgd (mg/1)
0.22
IWC (%)
7.36
Allowable Conc. (mg/1)
21.7
*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/l, 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)

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DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0 „pit Review NC0039420 Robinson, Caroline Outlook
RE: Draft Permit Review NCO039420
Kirby, Ben <[e-mail]>
Fri 1/12/2024 1:30 PM
To:Robinson, Caroline <[e-mail]>
Ca Fox, Shawn <[e-mail]>
Caroline,
The Public Water Supply Section concurs with the issuance of this permit provided the facility is
operated and maintained properly, the stated effluent limits are met prior to discharge, and the discharge
does not contravene the designated water quality standards.
Thanks,
Ben Kirby (he/him/his)
Assistant Regional Engineer, Winston-Salem Regional Office
Division of Water Resources, Public Water Supply Section
North Carolina Department of Environmental Quality
Office: [phone] 1 Cell: [phone]
450 West Hanes Mill Road, Suite 300, Winston-Salem, NC 27105
[e-mail]
NORTH CAROLINAD_ E Q
Department of Environmental Duality
Email correspondence to and from this address is subject to the North
Carolina Public Records Law and may be disclosed to third parties.
From: Robinson, Caroline <[e-mail]>
Sent: Thursday, January 11, 2024 2:54 PM
To: Talbott, Jeffrey <[e-mail]>; Graznak, Jenny <[e-mail]>; Kirby, Ben
<[e-mail]>
Subject: Draft Permit Review NCO039420
Hi Jenny, Ben, and Jeffrey,
The NCO039420 draft permit renewal is ready for review! The draft permit renewal for the 1-77 Rest Area WWTP
(NC0039420) will go to Notice on 1/23/2024. Please send me any comments as time permits.
Thanks,
Caroline
Caroline Robinson (she/her/hers)
Environmental Specialist 11, Division of Water Resources
North Carolina Department of Environmental Quality
Office: [phone] / Cell: [phone]
caroline.robinsonCa deq.nc.gov
about:blank?windowld=SecondaryReadingPane3 1/2

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0
NORTH CAROLINA
SURRY COUNTY
AFFIDAVIT OF PUBLICATION
Before the undersigned, a Notary Public of said County and State, duly
commissioned, qualified and authorized by law to administer oaths,
personally appeared Sandra Hurley who being first duly
sworn, deposes and says: that he (she) is Regional Publisher
(Publisher or other officer or employee authorized to make affidavit) of
ADAMS PUBLISHING GROUP, LLC, engaged in the publication of a
newspaper known as MOUNT AIRY NEWS, published, issued, and
entered as periodicals class mail in the city of Mount Airy in said County
and State; that he (she) is authorized to make this affidavit and sworn
statement; that the notice or other legal advertisement, a true copy of which
is attached hereto, was published in MOUNT AIRY NEWS on the
following dates:
,95-a4
and that the said newspaper in which such notice, paper, document or
legal advertisement was published was, at the time of each and every such
publication, a newspaper meeting all of the requirements and
qualifications of Section 1-597 of the General Statutes of North Carolina
and was a qualified newspaper within the meaning of Section 1-597 of the
General Statutes of North Carolina.
This a54-A day of � 014A&QAeW , 2024
Signature of person making affidavit
Sworn to and subscribed before me, this C U day of
52024
Notary Public
My Commission expires:
EMy
JENNAJOHNSON
tary Public - North Carolina
Surry County
mmission Expires September 13. 20M
CLIPPING OF
LEGAL
ADVERTISEMENT
ATTACHED HERE
Public Notice
North Carolina
Environmental Management
Commission/NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
Notice of Intent to Issue a
NPDES Wastewater Permit
NCO039420 1-77 Rest Area
WWTP The North Carolina En-
vironmental Management
Commission proposes to issue
a NPDES wastewater dis-
charge permit to the person(s)
listed below. Written comments
regarding the proposed permit
will be accepted until 30 days
after the publish date of this
notice. The Director of the NC
Division of Water Resources
(DWR) may hold a public hear-
ing should there be a signifi-
cant degree of public interest.
Please mail comments and/or
information requests to DWR
at the above address. Inter-
ested persons may visit the
DWR at 512 N. Salisbury
Street, Raleigh, NC 27604 to
review the information on file.
Additional information on
NPDES permits and this notice
may be found on our website:
https://deq.nc.gov/public-no-
tices-hearings,or by calling
[phone]. The Virginia
DOT applied to renew NPDES
permit NCO039420 for the 1-77
Rest Area WWTP (Interstate
Highway 77 on the NC / VA
state line, Lambsburg) in Surry
County. This facility discharges
Naked Run Creek in the Yad-
kin -Pee Dee River Basin. Cur-
rently ammonia nitrogen, fecal
coliform, and total residual
chlorine (TRC) are water qual-
ity limited. This discharge may
affect future wasteload alloca-
tions in this portion of Naked
Run Creek.
Publish: 1-25-24 212869

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0 „pit Review NC0039420 Robinson, Caroline Outlook
RE: Draft Permit Review NCO039420
Talbott, Jeffrey <[e-mail]>
Tue 1/16/2024 10:01 AM
To:Robinson, Caroline<[e-mail]>;Graznak, Jenny <jen [e-mail]>; Kirby, Ben
< [e-mail]>
Hello Caroline,
Operator certification notes that this facility is classified as a Bio/WW-2, with the ORC and all Backup
ORC's active and in good standing with the program.
We have no comments at this time.
Thank you.
Jeff Talbott
Supervisor, NC Operator Certification Program
Division of Water Resources
Department of Environmental Quality
Phone: [phone]
Email: [e-mail]
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Robinson, Caroline <[e-mail]>
Sent: Thursday, January 11, 2024 2:54 PM
To: Talbott, Jeffrey <[e-mail]>; Graznak, Jenny <[e-mail]>; Kirby, Ben
<[e-mail]>
Subject: Draft Permit Review NCO039420
Hi Jenny, Ben, and Jeffrey,
The NCO039420 draft permit renewal is ready for review! The draft permit renewal for the 1-77 Rest Area WWTP
(NC0039420) will go to Notice on 1/23/2024. Please send me any comments as time permits.
Thanks,
Caroline
Caroline Robinson (she/her/hers)
Environmental Specialist 11, Division of Water Resources
North Carolina Department of Environmental Quality
about:blank?windowld=SecondaryReadingPane4 1/2

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0
From: Henry Garoan
To: SVC DEO.oubliccomments
Cc: Robinson. Caroline; Coco. Nick A; Bob Halstead; Patrick Hunter
Subject: [External] Comments on Draft NPDES Permit Nos. NCO039420 and NCO020800
Date: Friday, February 16, 2024 1:04:52 PM
Attachments: 2023.02.16 NPDES Permit Trout Water Comments.odf
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 afternoon,
On behalf of MountainTrue, North Carolina Trout Unlimited State Council, North Carolina Wildlife
Federation, and the Southern Environmental Law Center, please find attached our comments on two
recently noticed draft NPDES permits for wastewater treatment plants discharging into designated
trout waters.
Please let me know if you have any questions.
Sincerely,
Henry Gargan (he/him)
Associate Attorney
Southern Environmental Law Center
48 Patton Avenue, Suite 304
Asheville, NC 28801
Office: [phone]
Direct: [phone]
Fax: [phone]
haaraan(a)selcnc.ora
southernenvironment.org

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0
SOUTHERN 48 Patton Avenue, suite 304
ENVIRONMENTAL Asheville, NC 28801
LAW
CENTER
February 16, 2023
Via Email
Richard Rogers
N.C. Dept. of Environmental Quality
Division of Water Resources
Water Quality Permitting Section
1617 Mail Service Center
Raleigh, NC 27699-1617
[e-mail]
Telephone [phone]
Facsimile 828-258-2024
Re: Application of the trout waters temperature standard in draft NPDES Permit
Nos. NC039420 and NC0020800.
Dear Mr. Rogers,
Please accept the following comments submitted on behalf of MountainTrue, North
Carolina Trout Unlimited State Council, North Carolina Wildlife Federation, and the Southern
Environmental Law Center related to the North Carolina Department of Environmental Quality's
("DEQ") failure to apply the required trout waters temperature standard in two recently noticed
draft National Pollutant Discharge Elimination System ("NPDES") permits: Draft Permit Nos.
NCO039420 (I-77 Rest Area WWTP) and NCO020800 (Andrews WWTP). These permits would
all authorize discharges into designated trout waters.'
We also note the same shortcomings in three permits for which the comment period
expired in December 2023: NPDES Permit Nos. NCO038977 (Roaring Gap Club WWTP),
NCO043125 (Patterson School), and NCO087700 (Westview Estates WWTP).2
Proper application of the trout waters temperature standard in these permits is critical to
protecting trout populations in North Carolina —particularly for dischargers with histories of
noncompliance. Unfortunately, both draft permits leave the affected populations at risk by failing
to ensure trout streams remain sufficiently cool. DEQ must correct this error in the final permits.
I. Trout require cold, clean water to survive.
Keeping water temperature in designated trout waters below certain thresholds is
critically important because North Carolina's three species of trout —brook trout, brown trout,
and rainbow trout —require cold, clean, oxygen -rich water to survive and thrive. Water
' See NPDES Draft Permit Nos. NCO039420 (I-77 Rest Area) (Jan. 23, 2024), at 2 (noting discharge into Naked Run
Creek, a WS-IV trout water in the Yadkin -Pee Dee River Basin); and NCO020800 (Andrews WWTP) (Jan. 9,
2024), at 2 (noting discharge into the Valley River, a Class C trout water in the Hiawasee River Basin).
2 See NPDES Draft Permit Nos. NCO038977 (Roaring Gap Club WWTP) (Nov. 28, 2023), at 2 (noting discharge
into an unnamed tributary to the Mitchell River, a Class B trout water and ORW in the Yadkin —Pee Dee River
Basin); NCO043125 (Patterson School WWTP) (Nov. 14, 2023), at 2 (noting discharge into the Yadkin River, a
Class C trout water in the Yadkin —Pee Dee River Basin); and NCO087700 (Westview Estates WWTP) (Nov. 14,
2023), at 2 (noting discharge into the Nantahala River, a Class B trout water in the Little Tennessee River Basin).
Charlottesville Chapel Hill Atlanta Asheville Birmingham Charleston Nashville Richmond Washington, DC

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0
temperature for these trout generally needs to be kept below 20 °C (68 °F).3 Unfortunately, past
and ongoing land management practices and wastewater discharges threaten trout habitats,
including by increasing stream temperatures. As we explained in our comments on North
Carolina's draft 2022 Clean Water Act Section 303(d) list, numerous trout streams routinely
exceed safe water temperatures for trout.4
Climate change is exacerbating this problem by placing additional thermal pressure on
water temperatures. By 2060, western North Carolina is predicted to see 10-20 more days each
year with air temperatures above 35 °C (95 OF), increasing the potential for water temperatures to
rise above 21.1 °C (70 OF) —levels that can be lethal to trouts This combination of past habitat
loss, ongoing poor land management practices, and climate change poses an existential threat to
many western North Carolina trout populations.
Declines in trout populations —driven by increasing stream temperatures or otherwise
will hurt local economies. The total economic benefit of trout fishing in North Carolina is
estimated at $1.38 billion annually, supporting nearly 11,808 jobs.6 If trout habitats are further
reduced, these economic benefits will be at risk. Overall, stream temperatures in North Carolina
are increasing, and this trajectory is predicted to continue under a changing climate. To protect
trout populations and the businesses that rely on them, North Carolina must take proactive steps
to ensure trout waters remain sufficiently cold.
IL North Carolina promulgated a temperature water quality standard to protect
trout.
Recognizing that trout require cold water, North Carolina exercised its authority under
the Clean Water Act to develop a temperature water quality standard designed to keep trout
streams cold. The Clean Water Act requires states to designate "uses" of waterbodies and
promulgate standards to protect those uses. See 33 U.S.C. § 1313; 40 C.F.R. § 131.10; N.C. Gen.
Stat. § 143-214.1. All waterbodies in North Carolina are subject to a temperature standard to
protect their associated designated use. 15A N.C. Admin. Code 2B.0211(18). Some North
Carolina waterbodies have been assigned a "trout waters" use. See 15A N.C. Admin. Code
2B.0301(b)(3) (explaining trout waters classification); 40 C.F.R. § 131.10(c) ("States may adopt
sub -categories of a use and set the appropriate criteria to reflect varying needs of such sub-
categories of uses, for instance, to differentiate between cold water and warm water fisheries.").
3 Trout Species of North Carolina, Fly Fishing NC (accessed Dec. 16, 2022), https://www flyfishingnc.com trout-
species-of-north-carolina.
4 S. Emil. L. Ctr., Comments on North Carolina's Draft 2022 § 303(d) List (Feb. 28, 2022).
5 Emma Johnson, Climate Change Challenges Trout Industry in North Carolina, Carolina Public Press (Feb. 17,
2021), https://carolinapublicpress.org/42527/climate-change-challenges-trout-industry-in-north-carolina/. See also
Kunkel, K.E., et al., North Carolina Climate Science Report (2020), available at
https://ncics.org/wpcontent/uploads/2020/10/NC_Climate_Science_Report FullReport_Final_revised_September20
20.pdf.
6 N.C. Wildlife Res. Comm'n, Socioeconomic Impact of Trout Fishing in North Carolina Survey
(2022), available at https://www ncwildlife.org/Fishing/Fishing-in-North-Carolina#87842458-mountain-trout-
information.
2

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0
The temperature standard —for both trout waters and non -trout watersprovides that water
temperature is:
not to exceed 2.8 degrees C (5.04 degrees F) above the natural water temperature,
and in no case to exceed 29 degrees C (84.2 degrees F) for mountain and upper
piedmont waters and 32 degrees C (89.6 degrees F) for lower piedmont and coastal
plain waters; the temperature for trout waters shall not be increased by more than
.5 degrees C (0.9 degrees F) due to the discharge of heated liquids, but in no case
to exceed 20 degrees C (68 degrees F).
15A N.C. Admin. Code 02B .0211(18)
The standard has two partsa delta limit and an absolute limit. In non -trout waters, the
delta limit prohibits an increase attributable to a discharger of more than 2.8 °C above the natural
water temperature. The absolute limit provides that temperature shall "in no case" exceed 29 °C
in mountain and upper piedmont waters and 32 °C in lower piedmont and coastal plain waters
regardless of the presence of permitted dischargers.
The trout waters standard follows this same structure: Stream temperature may not be
increased "by more than .5 degrees C ... due to the discharge of heated liquids" but "in no case"
shall stream temperature exceed 20 'C. This makes sense because keeping trout waters below
20 'C—regardless of the presence of permitted dischargers —is critical to sustaining healthy trout
populations.
North Carolina's temperature standard, including for trout waters, is implemented in part
through NPDES permits that regulate point source discharges by setting limits and monitoring
requirements for a variety of water quality characteristics. 33 U.S.C. § 1342(a). State agencies
with delegated authority to administer the NPDES program, such as DEQ, are responsible for
ensuring NPDES permits identify and apply the correct water quality limits for the receiving
waterbody.
In issuing a recent NPDES permit for a discharge into a designated trout water without
the required temperature standards, DEQ explained it had concluded that "effluent from 100%
domestic WWTPs is not a heated liquid, as specified in the Rule" and, presumably, that the trout
waters temperature standard therefore did not apply.' This conclusion is unsupported by the text
and the purpose of the rule; it is also irrelevant to the absolute limit set by the standard:
Temperature in trout waters shall "in no case ... exceed 20 degrees C." 15A N.C. Admin. Code
2B.0211(18) (emphasis added). DEQ must include limitations in permits to ensure that
discharges do not cause or contribute to an exceedance of the 20 °C standard, even if that
effluent is not purposefully heated prior to discharge. In the final fact sheet for these permits or
elsewhere, we respectfully request that DEQ explain how it determined that "effluent from 100%
domestic WWTPs" is not subject to the trout waters temperature standard.
'Expedited Fact Sheet for NPDES Permit No. NCO050610 (September 2023), at 2.

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III. DEQ must ensure both draft NPDES permits comply with the trout waters
temperature standard.
As we have explained to the agency before, to comply with the Clean Water Act and state
water quality standards DEQ must ensure both draft NPDES permits facilitate compliance with
the temperature limits necessary to protect trout waters. The draft permits out for comment
currently contain no language to prevent exceedances of those standards, although the draft
permit for the I-77 Rest Area WWTP includes new in -stream monitoring requirements for
turbidity and dissolved oxygen.' The draft permit for Andrews WWTP likewise proposes several
significant additions to that permit's slate of monitoring requirements,' which we agree are
highly necessary given the seriousness and frequency of recent violations by that facility.10 We
applaud DEQ for taking notice of the importance of monitoring for the protection of trout waters.
That said, the I-77 Rest Area WWTP draft permit only requires weekly effluent,
upstream, and downstream temperature monitoring." We are pleased to see the Andrews WWTP
draft permit require daily temperature monitoring, but only of its effluent.12 Both permits should
require daily monitoring for temperatureupstream, downstream, and effluent. Without data
about upstream water temperature, the discharger cannot effectively comply with North
Carolina's "delta" standard for stream temperature.
But most importantly, the final documents must include permit limits to prevent
violations of water quality standards, including the trout waters temperature standard.
The draft permit for the both the I-77 Rest Area WWTP and Andrews WWTP
exemplifies why permit limits for temperature are necessary. Andrews' application materials
indicate a maximum summer effluent temperature of 25.7 °C, far exceeding the 20-degree
maximum set for trout waters.13 In fact, the reported average summer effluent temperature is
22.5 °C.14 The application for the I-77 Rest Area WWTP contains almost identical temperature
data: a maximum summer temperature of 25 °C and an average summer temperature of 22.5
°C 15 There is therefore a substantial risk that both dischargers will violate both the delta and
absolute temperature limits applicable to discharges to trout waters.
To be clear, DEQ has no authority to issue NPDES permits that do not ensure compliance
with water quality standards, including the trout waters temperature standard. See 33 U.S.C. §
s Letter from Caroline Robinson, N.C. Dep't of Envt'l Quality, to Allen Campbell, State Program Manager, Va.
Dep't of Transp., regarding Draft NPDES Permit No. NC0039420. (Jan. 23, 2024), at 1.
9 Letter from Nick Coco, N.C. Dep't of Envt'l Quality, to James Reid, Mayor, Town of Andrews, regarding Draft
NPDES Permit No. NCO020800 (Jan. 9, 2024), at 1.
10 See N.C. Dep't of Envt'l Quality, Division of Water Resources, Civil Penalty Assessment against Town of
Andrews (Jan. 17, 2024) (noting ammonia limit exceeded by 48.8% and that the facility had received three civil
penalty assessments within the preceding 12 months).
11 Draft NPDES Permit No. NC0039420, at 3 (setting "weekly" frequency for both effluent, upstream, and
downstream temperature monitoring).
12 Draft NPDES Permit No. NC0020800, at 3 (requiring "daily" monitoring for temperature, but only of the effluent
itself).
13 Renewal Application for NPDES Permit No. NCO020800 (Andrews WWTP) (Feb. 24, 2023), at 6.
14 Id
" Renewal Application for NPDES Permit No. NCO039420 (I-77 Rest Area WWTP) (Nov. 2, 2023), at 11.
2

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1311(b)(1)(C) (requiring NPDES permits to include limitations "necessary to meet water quality
standards"); 40 C.F.R. § 122.44(d)(1). Where draft permits fail to ensure compliance, they must
be revised.
Incorporating the trout waters temperature standard into permits is also important because
DEQ has failed to correctly apply this standard when preparing its Clean Water Act Section
303(d) list. Section 303(d) requires states to identify waterbodies that are not meeting water
quality standards, investigate the reasons for noncompliance, and develop a plan to remediate
those problems. For several years, DEQ has wrongly applied in the Section 303(d) context the
water quality temperature standard for mountain waters (29 °C) to designated trout waters
protected by the 20 °C standard.16 This wrongful application extends to the Valley River and the
Yadkin River." The combination of these two errors —failure to include temperature standards
in NPDES permits and failure to assess compliance with the correct temperature standard in the
Section 303(d) context —generally risks jeopardizing trout populations.
In summary, before finalizing either of these permits, DEQ must ensure they facilitate
compliance with the water quality temperature standard for trout waters. The most
straightforward and thorough approach is to include language DEQ has already properly applied
to other trout water discharge permits:
"The instream temperature shall not be increased by more than 0.5 degrees C (0.9
degrees F) due to the discharge of heated liquids, but in no case to exceed 20
degrees C (68 degrees F). If the stream temperature exceeds 20 degrees C due to
natural background conditions, the effluent cannot cause any increase in instream
water temperature."
This expression of the temperature standard, found in the most recent draft NPDES
permit for the Buffalo Meadows WWTP, NPDES Permit No. NCO030325 (and others), correctly
requires permittees to cause no further increase in temperature when stream temperature already
exceeds trout water standards.
IV. Conclusion
North Carolina has some of the best and most at -risk trout habitat in the eastern United
States. Ensuring viable trout populations persist in the future requires keeping trout streams clean
and cold. To that end, DEQ must forthrightly apply the trout waters temperature standard in the
final versions of NPDES Permit Nos. NCO039420 and NC0020800.
Please notify Henry Gargan at [e-mail] or 828-258-2023 when DEQ issues
final versions of these NPDES permits. We remain available as always to discuss our concerns.
16 See supra note 4.
17 See id at 6; North Carolina Integrated Report (2022), at 486, 1177.
5

DocuSign Envelope ID: DE122FEF-9179-480A-8916-8B18FF97EDC0
Sincerely,
Henry Gargan
Associate Attorney
Southern Environmental Law Center
hear an e,selcnc.org
Patrick Hunter
Managing Attorney
Southern Environmental Law Center
CC: Nick Coco (nick.coco(2deq.nc.gov)
Caroline Robinson (caroline.robinsongdeq.nc.gov).

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Water Resources
ENVIRONMENTAL QUALITY
Memorandum
To:
From:
Date:
Subject:
PAT MCCRORY
Governor
DONALD R. VAN DER VAART
NPDES Complex Unit
Tom Belnick
July 20, 2016
NPDES Permitting Guidance
NPDES Implementation of Ammonia Criteria- Update
secrelaly
S. JAY ZIMMERMAN
Director
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/l, 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 Permittee.
• 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

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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.

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i
AMMONxA CRTTERTA TABLES (NH3 as N)
Based on EPA recommended 4-day maximum average concent.ration criteria
(Mou'ntain'sand Trout Waters
TEMPERATURE
H 120C 230C .
6.8 1.8084 1.0028 Total Ammonia
7.5 1,.8084 1.0111 (mg/l NH3 as N)
Pie•dmon:t Freshwaters
r
TEMPERATURE
H 140C 2 60C
6.8 1.8084 1.1344 Total Ammonia
7.5 1.8084 1.1541 (mg/1 NH3 as N)
Coast:Al Plain and Sandhills Freshwaters
TEMPERATURE
H 160C 280C
6.8 1.7920 0.9700 Total Ammonia
7.5 1.7920 0.9864 (mg/1•NH3 as N)
S
Ex

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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/I, 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)