WQ0000795_Speculative Limits_20230714

DocuSign Envelope ID: 305E55C3-7D77-415F-AB85-EEC9BFE9943B
ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
RICHARD E. ROGERS, JR.
Director
Mr. Kyle Breuer, Town Manager
Town of Surf City
P.O. Box 2475
Surf City, NC 28445
Dear Mr. Breuer:
NORTH CAROLINA
Environmental Quality
7/14/2023
Subject: Speculative Effluent Limits
Surf City Discharge to Northeast Cape Fear River
NPDES Permit No. WQ0000795
Pender County
Cape Fear Basin
The Town of Surf City provided a model evaluation results memo to the Division of Water Resources (DWR)
on April 18, 2023, for a new discharge into the Northeast Cape Fear River. The DWR Modeling and
Assessment Branch (MAB) and Municipal Permitting Unit (NPDES) has completed our assessment of this
material and the following speculative effluent limits have been developed.
Receiving Stream. The Northeast Cape Fear River is located within the Cape Fear River Basin. The Northeast
Cape Fear River has a stream classification of C-Swamp (C-Sw). as provided in G.S. 143-215.1(c7),
discharges to such surface waters shall not cause a reduction in the dissolved oxygen levels of more than 0.10
mg/1 below the approved modeled instream dissolved oxygen level for the surface waters. The 7Q10 could
not be obtained from the closest USGS stream gage, Station 02108566 (Northeast Cape Fear River near
Burgaw, NC), as that gage is under tidal influence.
The Northeast Cape Fear River at the outfall location [stream segment 18-74-(29.5), from Rock Fish Creek to
N.C. Hwy. 210] is not currently listed as an impaired waterbody on the 2022 North Carolina 303(d) Impaired
Waters List.
Based upon a review of information available from the North Carolina Natural Heritage Program Online Map
Viewer, there are no Federally Listed threatened or endangered aquatic species identified within a 5-mile radius
of the proposed discharge location. If there are any identified threatened/endangered species, it is recommended
that the applicant discuss the proposed project with the US Fish and Wildlife Service to determine whether the
proposed discharge location might impact such species.
Speculative Effluent Limits. Based on the revised materials provided, NPDES concludes that a new discharge
of 2.32 MGD should include the following permit limits (in Table 1). A complete evaluation of these limits
and monitoring requirements for metals and other toxicants, as well as potential instream monitoring
requirements, will be addressed upon receipt of a complete NPDES permit application.
North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 1 1617 Mail Service Center I Raleigh, North Carolina 27699-1617
NORTH CARCLINA
919.707.9000

DocuSign Envelope ID: 305E55C3-7D77-415F-AB85-EEC9BFE9943B
Every applicant shall also submit documentation of any additional pollutants for which there are certified
methods with the permit application if their discharge is anticipated. These pollutants may be found in 40
CFR Part 136, if there are additional pollutants with certified methods to be reported, please submit the
Chemical Addendum to NPDES Application and, if applicable, list the selected certified analytical method
used.
TABLE 1. Speculative Limits for the proposed Surf City Discharge to Northeast Cape Fear River
(2.32 MGD)
EFFLUENT
CHARACTERISTICS
EFFLUENT LIMITS
Monthly
Average
Weekly
Average
Daily
Maximum
Flow
2.32 MGD
BOD5, 20°C — Summer'
5.0 mg/L
7.5 mg/L
BOD5, 20°C - Winter'
10.0 mg/L
15.0 mg/L
Dissolved Oxygen (DO) (minimum)
Daily average > 7.0 mg/l
TSS
30 mg/L
45 mg/L
NH3 as N - Summer'
1.0 mg/L
4.5 mg/L
NH3 as N - Winter'
2.0 mg/L
9.0 mg/L
Total Nitrogen
15.0 mg/L
Total Phosphorus
5.0 mg/L - Monthly
Total Residual Chlorine
28 ug/L
Fecal coliform (geometric mean)
200/100 mL
400/100 mL
Chronic Toxicity Pass/Fail (Quarterly test)
90%2
PFAS Monitoring (EPA Method 1633)3
M/R Quarterly
' Summer: April 1 — October 31 *Winter: November 1 — March 31
2 Subject to change.
3 The PFAS requirements will be effective six months after EPA publishes final Method 1633.
After reviewing the model and results, DWR recommends [to minimize water quality impact while allowing
for the discharge, especially given that the Northeast Cape Fear River discharges into the Lower Cape Fear
River, which is already impaired for DO] the installation of an appropriately designed diffuser to provide mixing
across the eight vertical layers. In addition, instream sampling for dissolved oxygen, pH, temperature, upstream
and downstream of the proposed discharge location would be included in any NPDES permit for this project.
Engineering Alternatives Analysis (EAA). Please note that the Division cannot guarantee that an NPDES permit
for a new or expanding discharge will be issued with these speculative limits. Final decisions can only be made
after the Division receives and evaluates a formal permit application for the expanded discharge.
In accordance with North Carolina Administrative Code 15A NCAC 214.0105(c), the most environmentally
sound alternative should be selected from all reasonably cost-effective options. Therefore, as a component of
all NPDES permit applications for new and expanding flow includes a detailed engineering alternatives analysis
(EAA) that must be prepared.
The EAA must justify the requested design flow and provide an analysis of potential wastewater treatment
alternatives. A copy of the Division guidance for preparing EAA documents is attached and/or can be found
online at:
httDs://files.nc. Lyov/ncdea/Surface%20Water%2OProtection/NPDES/Hermits/eaa-guidance-20140501-
dwr-swp-npdes_13.pd£
REQ5 North Carolina Department ofEnvironmental Quality I Division ofWater Resources
512 North Salisbury Street 1 1617 Mail Service Center I Raleigh, North Carolina 27699-1611
NORTH CAROLINA 919.707.9000
onparhnem of EmironmanW 9uallly

DocuSign Envelope ID: 305E55C3-7D77-415F-AB85-EEC9BFE9943B
State Environmental Polices (SEPA) EA/EIS Requirements. A SEPA EA/EIS document may be required
for projects that: 1) involve $10 Million or more of state funds; or 2) will significantly and permanently
impact 10 or more acres of public lands. Please check with the DWR SEPA coordinator (David Wainwright,
919-707-9045) as to whether your project requires SEPA review. For projects that are subject to SEPA, the
EAA requirements discussed above will need to be folded into the SEPA document. If required, a FONSI
must be issued prior to issuance of the NPDES permit for the expansion. Details related to FONSI can be
found on-line at: https://deq.nc.gov/permits-regulations/sepa/review-process and at:
https: //deq.nc. gov/about/divisions/water-infrastructure/documents/cdbgi-fonsiea
We understand this expansion project is moving forward rapidly; however, we would expect that any request
for NPDES permitting action for the expansion at either flow noted be taken within a five-year period from
the date of this letter, or the noted speculative limits in Table 1 would be subject to reassessment and review.
Should you have any questions about these speculative limits or NPDES permitting requirements, please feel
free to contact Kristin Litzenberger at [phone] / kristin.litzenbergerkncdenr.gov or Michael Montebello
at Michael.Montebellokncdenr.gov.
Respectfully,
Do'c'fu,Si-gne'Id byy:k A A
C464531431644FE...
Michael Montebello
NPDES Program Branch Chief
Attachment: Link to EAA Guidance Document, Chemical Addendum Form, and NPDES application information:
hLtps:Hdeq.nc. gov/about/divisions/water-resources/water-quality-pennittine/ni)des-wastewater/npdes-permitting-process/npdes-
individual-permit-applications
ec: NPDES Files [Laserfiche]
Town of Surf City / Kyle Breuer, Town Manager [[e-mail]]; David Price [[e-mail]]
HDR / Kim Colson, P.E. [[e-mail]]; Adam Sharpe [[e-mail]]
Highfill Infrastructure Engineering, P.C. / Ray Cox [[e-mail]]; Vance Brooks [[e-mail]];
Ward and Smith, P.A. / Whitney Campbell Christensen[[e-mail]]; Trafton Dinwiddie
[[e-mail]]
DWR / Michael J Montebello [[e-mail]]; Richard Rogers [[e-mail]]; [Julie Grzyb
[e-mail]]; Pam Behm [[e-mail]]
DEQ Administration / Shrikar Nunna [[e-mail]]; Skyler Golann [[e-mail]]
DWI / Corey Basinger [[e-mail]]
Wilmington Regional Office / Morella S. King [[e-mail]]
NC WRC / Maria Dunn [[e-mail]]
US FWS / Sara Ward [sara [e-mail]]
DWR / Basinwide Planning / Nora Deamer [[e-mail]]
REQ5 North Carolina Department ofEnvironmental Quality I Division ofWater Resources
512 North Salisbury Street 1 1617 Mail Service Center I Raleigh, North Carolina 27699-1611
NORTH CAROLINA 919.707.9000
onparhnem of EmironmanW 9uallly