WQ0034367_Correction Request_20220822

C�
ONWASA
August 18, 2022
NCDEQ — Division of Water Resources
Water Quality Permitting Section
Non -Discharge Permitting Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
Attn: Lauren Raup-Plummer, PE
Re: Permit No. WQ0034367
Northwest Regional WWTP and High -Rate Infiltration System, Onslow County
Request for Permit Modification
Dear Ms. Raup-Plummer:
The Onslow Water and Sewer Authority (ONWASA) recently received a renewed
operating permit for the above -referenced facility. During the renewal process, four references
within the facility description (on the first page of the draft permit) were found to be incorrect,
however the necessary revisions were not submitted in time to be addressed in the final permit.
As a follow-up to a recent conversation on this subject, this letter shall serve as ONWASA's formal
request for a permit modification to incorporate these changes:
Page 1, Second Section, Lines 2 and 3
...one fine screen grit removal system served by t-we one 1.3 cubic foot per minute (CFM) positive
displacement blowers;...
Page 1, Second Section, Lines 10 and 11
...an 822, 000-gallon post flow equalization basin with Avg one 4,943 GPM jet motive mixing
pumps; .. .
Page 1, Second Section, Lines 12 and 13
... two tertiary disc filter units with one 5,000 GP gallon backwash water supply tank...
Page 1, Second Section, Lines 15, 16 and 17
... a 75, 000-gallon chlorine contact basin served by a 2, 500-gallon sodium hypochlorite tank with
two 00 40 gallon per hour (GPH) peristaltic chemical metering pumps;...
If you have any questions or need additional information on this request please
feel free to contact me directly at 910-937-7521 or dmohr(aonwasa.com.
C: Permit File
Sincerely,
A6L I I PC -
David M. Mohr, P.E.
Chief Operations Officer
Onslow Water and Sewer Authority
228 Georgetown Road • Jacksonville, NC 28540 • Tel [phone] • Fax [phone] • www.onwosa.com

NORTH CAROLINA
ENVIRONMENTAL MANAGEMENT COMMISSION
DEPARTMENT OF ENVIRONMENTAL QUALITY
RALEIGH
HIGH -RATE INFILTRATION SYSTEM PERMIT
In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as
amended, and other applicable Laws, Rules, and Regulations
PERMISSION IS HEREBY GRANTED TO
Onslow Water and Sewer Authority
Onslow County
FOR THE
operation of a 1,272,973 gallon per day (GPD) wastewater treatment and high -rate infiltration facility
consisting of the:
continued operation of a 2,000,000 GPD wastewater treatment facility consisting of a plant drain pump
station with two 1,400 gallon per �rjjinute (GPM) submersible pumps; an influent flow meter; one fine screen
grit removal system served by-t�e 1.3 cubic foot per minute (CFM) positive displacement blowej; a bypass
manually -cleaned coarse screen; a flow splitter box; an influent composite sampler; two 1,830,000 gallon
sequencing batch reactors (SBRs) served by five 1,156 CFM positive displacement blowers, three 9,886
GPM axial flow jet motive pumps, an SBR influent transfer pump station with two 3,400 GPM centrifugal
pumps, and a waste activated sludge (WAS) pump station with three 516 GPM centrifugal pumps; two
614,000 gallon aerobic sludge digesters served by three 780 CFM positive displacement blowers, a WAS
flow meter, one 4,395 GPM jet -motive mixing pump, two 350 GPM centrifugal sludge transfer pumps, two
250 GPM submersible supernatant pumps, and a supernatant flow meter; an 822,000 gallon post flow
equalization basin with=4,943 GPM jet motive mixing pumpXand three 1,400 GPM centrifugal transfer
pumps; a post flow equalization basin flow meter; two tertiary disc filter units with one 5,000 MdOM &A 00
backwash water supply tank, two 98 GPM primary backwash pumps, and two 98 GPM auxiliary backwash
pumps; a 3,472 GPM ultraviolet (UV) disinfection system consisting of a 1,000 gallon open -vessel UV
tank with three banks in series each containing 32 UV lamps per bank (96 lamps total); 5,000 gallon
chlorine contact basin served by a 2,500 gallon sodium hypochlorite tank with two Ion per hour
(GPH) peristaltic chemical metering pumps; an 11,500 gallon effluent pump station with three 1,850 GPM
submersible pumps; an effluent residual chlorine analyzer; an effluent sampler with a hose pump; a
turbidimeter; a 1,500 kilowatt (kW) automatically activated auxiliary generator; an alum feed system with
a 7,000 gallon tank and three 40 GPH peristaltic chemical metering pumps; a sodium hydroxide feed system
with a 10,000 gallon tank and three 40 GPH peristaltic chemical metering pumps; a micro-C glycerin feed
system with a 10,000 gallon tank and two 40 GPH peristaltic chemical metering pumps; two synthetically -
lined 5-day upset basins served by the aforementioned plant drain pump station with both basins having an
effective volume of 2,734,829 gallons; and all associated piping, valves, controls, and appurtenances; the
continued operation of a non -potable reuse system for internal use within the treatment plant works deemed
permitted pursuant to under 15A NCAC 02U .0113(a)(16) and consisting of two 170 GPM submersible
pumps; two 800-gallon steel hydropneumatic tanks; and all associated piping, valves, controls, and
appurtenances; the
WQ0034367 Version 3.0 Shell Version 200201 Page 1 of 11