NC0073539_Draft_FactSheet_20231020

Fact Sheet for Permit Renewal
Oct 2023 - NPDES Permit NC0073539 - Page 1

NCDEQ / DWR / NPDES
EXPEDITED FACT SHEET - NPDES PERMIT RENEWAL
NPDES Permit NC0073539

Caroline Robinson / Compliance & Expedited Permitting Unit / [e-mail] / Oct 2023
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
Address/Mailing Address 12309 Ramah Creek Court, Huntersville, NC 28078
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
Classification C
Stream Segment 13-17-4-4 Outfall Lat. 35° 26' 38" N
7Q10 - Summer (cfs) 0.075 Outfall Long. 80° 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) /
33.16% (winter) 303(d) List No

BASIC INFO FOR EXPEDITED PERMIT RENEWAL
Does permit need Daily Max NH3 limits?
Already present in permit; however, revised ammonia
limits, based on the IWC calculations and 2016 NH3
guidance document, will take effect on 1/1/2028. 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.
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
Oct 2023 - NPDES Permit NC0073539 - Page 2

⬧ 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 NH3 guidance document,
that will take effect on 1/1/2028. 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)

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.