HomeMy WebLinkAboutNC0089613_Fact Sheet_20220421Permit NC0089613
DENR/DWR
FACT SHEET FOR PROPOSED NPDES PERMIT
NPDES Permit NC0089613
Facility Information
Applicant:
Brunswick Regional Water and Sewer H2G0
Applicant Address:
P.O. Box 2230, Leland, NC 28451
Facility Name/Address:
Brunswick Regional Water and Sewer H2G0 Water Treatment Plant
146 Gregory Road, Belville, NC 28451
Permitted Flow
Discharge estimates: 1.0 MGD with a 4 MGD potable water system, and
1.5 MGD with a 6 MGD potable water system, and
2.0 MGD with an 8 MGD potable water system
Type of Waste:
RO concentrate wastewaters and flush waters
Facility/Permit Status:
PC-1
County:
Brunswick County
r Miscellaneous
Permit Status:
New
Regional Office:
Wilmington
Receiving Stream/ Basin:
Brunswick River/ Cape Fear
River Basin
State Grid / USGS Quad:
Belville
Stream Classification:
SC
8-Digit HUC:
03030005
303(d) Listed?
Yes, for DO
Date:
August 23, 2016
Revised April 27, 2017
Subbasin/Index:
03-06-17 / 18-77
Diffuser Location:
•
Lat. 34° 13' 05" N Long.77° 58' 42" W
Drainage Area (mi2):
Tidal
7Q10s (cfs)
Tidal
7Q10w (cfs)
Tidal
Average Flow (cfs):
Tidal
IWC (%):
Modelled: 1.6 % at 1.0 MGD
2.1 % at 1.75 MGD
Used 2.1 % for chronic tox test
Facility and Discharge:
This is a permit for a Reverse Osmosis water treatment plant in Brunswick County.
Source water is supplied from the Lower Peedee Aquifer and the deeper Black Creek Aquifer. Analysis
of the raw water from wells in both aquifers were submitted for review during initial application for
permit. The RO water treatment plant primarily removes excess salts and minerals from the brackish
groundwater.
Two 2-MGD RO skids are mounted to produce 4 MGD of potable water. Raw water enters the plant and
an anti-scalant chemical is added at an approximate dose of 1 mg/L. The raw water then passes through
a 5-micron disposable cartridge filter for suspended solids removal. High pressure pumps will pressurize
the water to pass through a 2-stage reverse osmosis membrane system. The permeate water undergoes
post treatment with the addition of carbon dioxide followed by calcite filters, final pH adjustment,
chlorination and the addition of a polyphosphate corrosion inhibitor. Finished water will go to a
clearwell and elevated storage tank for distribution.
Membranes require an acid and basic chemical cleaning once a year and these wastewaters (24,000
gallons per 2-MGD skid) will be neutralized, as necessary, and discharged to the Belville WWTP.
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Permit NC0089613
Receiving Stream:
The Brunswick Regional Water and Sewer H2GO Water Treatment Plant was set to initially produce 4
MGD of potable water with a wastewater concentrate discharge of 1.0 MGD. For this renewal, they
requested an intermediate flow sheet representative of production of 6MGD potable water and 1.5 MGD
discharge. The RO concentrate generated from the RO Process will be discharged into the Brunswick
River one -mile south of the US-17-74-76 bridge, approximately 100 feet downstream from H2GO's
existing Belville Sanitary WWTP discharge. Wastewater will be discharged through a diffuser into the
Brunswick River using available RO treatment unit pressure. The Brunswick River is classified as a SC
receiving stream and is listed as impaired for low dissolved oxygen on the 2014 and draft 2016 303(d)
list.
The Permittee is a member of the Lower Cape Fear River Program, which conducts water quality
monitoring within the basin to gain a broad water quality perspective.
2021 renewal — proposed changes:
- For this renewal, the permittee has requested an intermediate 6 MGD potable water flowsheet between
the 4MGD potable water initial design and the 8 MGD final potable water design. The facility is still
under construction and has not discharged yet. While constructing the 4MGD potable water plant, the
facility submitted an ATC modification request to increase to 6 MGD due to recent addition of Leland
water customers to the H2GO service area. An intermediate flowsheet has been added to this draft permit
(Section A (2)).
- The footnote corresponding to each effluent table which previously required metals to be sampled in
conjunction with Whole Effluent Toxicity has been removed. This is no longer a requirement.
- The language in Section A (5) Chronic Toxicity Testing Pass/Fail Quarterly has been modified to
reflect the addition of the 6MGD potable design flow sheet, as well as to include instructions for
electronic submittal of results.
- The language in Section A (6.) Electronic Reporting Requirements has been modified to reflect the
most recent federal requirements for electronic reporting.
- The facility has not yet commenced discharge, so there is no monitoring data or compliance history to
be reviewed.
Modeling Analysis:
A modeling analysis of the proposed membrane filtration discharge was performed by Groundwater
Management Association, Inc. (GMA) and submitted as part of the NPDES application. GMA collected
surface water data and hydrologic ambient conditions to use in the simulation. GMA ran several
discharge configuration scenarios to determine an optimal diffuser design. Total Dissolved Solids (TDS)
was modeled as the representative mixing constituent to provide a dilution factor applicable to other
effluent parameters.
The proposed diffuser design is a multiport diffuser consisting of a 10-meter (32.8 ft) pipe with four
equally spaced ports with 0.26 ft openings angled at 45° located one foot above the bottom of the river.
Two flows were simulated to account for the initial discharge of 1 MGD and future expansion
discharging 1.75 MGD. For 1.75 MGD this design provides a discharge velocity of 3.8 m/s. For 1 MGD
the discharge velocity is 2.18 m/s.
The proposed mixing zone is at a distance of 10 meters from the diffuser. The modeled conditions for
this scenario used a maximum concentration of TDS for the effluent, the low TDS concentration in the
river, 1 hr after slack tide and tidal reversal of 12.5 h. This scenario used average current velocity as
measured by the field study.
EPA's Technical Support Document for Water Quality- Based Toxic Controls (TSD) gives
recommendations on outfall design and sizing of mixing zones. The proposed outfall design meets EPA
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Permit NC0089613
recommendation for discharge velocity and diffuser configuration. The TSD document doesn't provide
restrictions on the sizing of chronic mixing zones; however, states can determine what is the appropriate
mixing zone that protects the waterbody in accordance with the state mixing zone regulations.
The model was run at 1.75 MGD and 1 MGD using the same diffuser configuration. Corresponding
dilution at the edge of the mixing zone is as follows:
1.75 MGD 47:1 dilution at 10 m IWC = 2.1 %
1 MGD 62.1:1 dilution at 10 m IWC = 1.6 %
Acute Mixing zone:
The TSD does include restrictions for preventing lethality to aquatic organisms using the criteria
maximum concentration as the protection level. Using EPA recommendations from the TSD document
an acute mixing zone can also be established. Using the most restrictive condition in the TSD document
the model results predicted an acute dilution of 40.6 at 3.5 m from the diffuser resulting in 2.4% IWC. A
detailed memo on the evaluation of the CORMIX model is attached.
Permit Limit Development:
• Effluent Limitations and Monitoring Requirements. The effluent limitations and Monitoring
requirements listed in this permit are based on the 2009 Water Treatment Plant Permitting
Strategy developed as part of an inter -agency workgroup tasked to define pollutants of concern
contained in wastewaters discharged from membrane and ion exchange water treatment plants.
All limits and monitoring are in accordance with the strategy and NCAC TISA: 2B .0500.
Wastewaters from membrane water treatment systems are not considered to be oxygen
consuming wastewaters. Fluoride and iron are not monitored in this permit because there are no
saltwater WQS's for these parameters.
• NEW Discharge Permit Requirement. As a new discharge the following special condition was
added in Section A(6). In accordance with 40 CFR CFR 122.21(k)(5)(vi), no later than 2 years
after the commencement of discharge from the proposed facility the applicant is required to
complete and submit items V and VI of NPDES application Form 2C. Please note that all data
generated must be reported to the approved detection level or lower reporting level of the
procedure.
• Toxicity Testing. Toxicity testing using mysid shrimp was conducted on the concentrate from
the pilot studies. The first toxicity test included a full dilution range from 1.5 to 10% IWC with
all dilutions passing. The subsequent two toxicity tests were performed at an IWC of 3%, the
expected dilution, and both tests received a pass result.
To simplify the permit, chronic toxicity testing using mysid shrimp will be included in the
permit at an effluent concentration of 2.1 % (the greater of the two modeled dilutions) when the
wastewater discharge flow is 1 MGD or 2 MGD.
Basis for limitations and monitoring:
Total Residual Chlorine
NC WQS
pH
NC WQS & TISA: 02B .0500
Temperature
WTP Strategy
Conductivity
WTP Strategy & TISA: 02B .0500
Dissolved Oxygen
WTP Strategy
Salinity
_
WTP Strategy
Total Dissolved Solids
_
WTP Strategy / Pollutant of Concern (POC)
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Permit NC0089613
Turbidity
15A NCAC 2B .0500 Surface Water Monitoring
and EPA memo
Total Arsenic
WTP Strategy / POC
Total Chloride
WTP Strategy / POC
Total Chromium
WTP Strategy / POC
Total Copper
WTP Strategy / POC
Total Zinc
WTP Strategy / POC
Ammonia Nitrogen
WTP Strategy / POC
Total Nitrogen
15A NCAC 2B .0500 Surface Water Monitoring
Total Phosphorus
15A NCAC 2B .0500 Surface Water Monitoring
ChronicToxicity
1999 MOA with EPA
EPA Rating Evaluation:
It was determined that this municipal facility is not a major facility.
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LOCALiQ
StarNews I The Dispatch
Times -News
PROOF OF PUBLICATION
Deq-Division Of Water Res
Wren Thedford
Deq-Division Of Water Res
1617 MAIL SERVICE CENTER
Raleigh NC 27699
STATE OF NORTH CAROLINA, COUNTY OF NEW HANOVER
The Wilmington Star -News, a newspaper printed and published in
the city of Wilmington, and of general circulation in the County of
New Hanover, State of North Carolina, and personal knowledge of
the facts herein state and that the notice hereto annexed was
Published in said newspapers in the issue dated:
02/25/2022
and that the fees charged are legal.
Swom to and subscribed before on 02/25/2022
Legal Clerk
Notary, State of WI, County of Brown
My commision expires
Publication Cost: $234.30
Order No: 6961362
Customer No: 512930
PO #:
TIIIS IS NOT AN INVOICE!
Please do not use this form for payment remittance.
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# of Copies:
1
VICKY FELTY
Notary Public
State of Wisconsin
PO Box 631245 Cincinnati, OH 45263-1245
Public Notice
North Carolina Environmental
Management Commis-
sion/NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
Notice of Intent to Issue a
NPDES Wastewater Permit
NC0073181 Wilmington River
Road Terminal, and NC0089613
H2G0
The North Carolina Environmen-
tal Management Commission
proposes to issue a NPDES
wastewater discharge permit to
the person(s) listed below. Writ-
ten 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 hearing should there be a
significant degree of public inter-
est. Please mail comments and/or
information requests to DWR at
the above address. Interested
persons may visit the DWR at 512
N. Salisbury Street, Raleigh, NC
27604 10 review information on
file. Additional information on
NPDES permits and this notice
may be found on our website:
http://deq.nc.gov/about/divisions/
water-resources/water-resources-
permits/wastewater-
branch/npdes-wastewater/publ ic-
notices,or by calling (919) 707-
3601. Kinder Morgan Terminals
Wilmington, LLC [3340 River Rd,
Wilmington, NC 28401] has
requested renewal of permit
NC0073181 for its Wilmington
River Road Terminal in New
Hanover County. This permitted
facility discharges treated
stormwater to the Caper Fear
River in the Cape Fear River
Basin. Some parameters are
water quality limited. This
discharge may affect future allo-
cations in this segment of the
Caper Fear River. NPDES
permit number NC0089613:
Brunswick Regional Water &
Sewer H2G0 [ P.O. Box 2230,
Leland, NC 284511 has requested
a new permit, NC0089613, for a
wastewater discharge from a
proposed Reverse Osmosis water
purification system in Brunswick
County. This proposed Reverse
Osmosis water purification
system will discharge membrane
concentrate wastewaters to
Brunswick River in the Cape
Fear River Basin. Currently,
Total Residual Chlorine is water
quality limited. This discharge
may affect future allocations in
this segment of the Brunswick
River.
Page 1 of 1
Brunswick Regional
H GO
Water and Sewer
May 21, 2021
Mr. John Hennessy
Supervisor — Compliance & Expedited Permitting Unit
Division of Water Resources
Water Quality Permitting Section - NPDES
1617 Mail Service Center
Raleigh, NC 27699-1617
RE: NPDES Permit Renewal
Brunswick Regional Water & Sewer H2G0 WTP
Dear Mr. Hennessy:
DIVISION OF WATER RESOURCES
DIRECTORS OFFICE
MiaffilZie/
In accordance with the requirements for NPDES permit renewal, we are foil sally requesting
renewal of NPDES Permit #NC0089613 for the H2GO's new Reverse Osmosis Water Treatment
Plant (currently under construction). Discharge to the Brunswick River has not yet occurred and
therefore there is no discharge data provided in the permit renewal.
At the time of this permit renewal request, the WTP is under construction and an ATC
application has been submitted to Public Water Supply to increase the WTP capacity from 4.0
MGD to 6.0 MGD during initial construction of the WTP. This is required due to the recent
addition of Leland water customers to the H2GO service area system. The ATC has already
been submitted and reviewed by Public Water Supply and approval is expected shortly. We are
requesting that a 1.5 MGD discharge flow sheet be added to the NPDES permit as part of this
renewal and we are submitting the attached EPA Forms 1, 2E, and 2C.
Please find enclosed two (2) copies of the renewal application forms. If you should have any
questions or required additional information, please do not hesitate to contact me.
Sincerely,
`01
Bob Walker
Executive Director
bwalkeriit,H2GOonline.com
Enclosures: As noted above
cc: Carl Scharfe, the Wooten Company
PO Box 2230, 516 Village Rd NE www.H2GOonline.com OFFICE : 910-371-9949
Leland, NC 28451 FAX : 910-371-6441