WQ0007507_Speculative Limits_20200619

ROY COOPER
Governor ,e ...
MICHAEL S.REGAN
Secretory
S.DANIEL SMITH NORTH CAROLINA
Director Environmental Quality
June 19, 2020
Leo Greene, P.E.
Green Engineering
PO Box 609
Wilson, North Carolina 27893
Subject: Speculative Effluent Limits
Pasquotank Industrial Park
Permit No. WQ0007507
Pasquotank County
Pasquotank River Basin
Dear Mr. Greene:
We have reviewed your request for Speculative Limits for Pasquotank County to discharge up
to 2.0 MGD of wastewater to the Pasquotank River, classified WS-IV; Swamp waters, in the
Pasquotank River Basin. After careful consideration, we cannot provide speculative limits for 1
a discharge at the provided location. Given the limitations of naturally occurring low dissolved
oxygen in swamp waters, and likely interaction with Elizabeth City's effluent, the Division is
not able to assess potential instream dissolved oxygen level impacts resulting from a new
discharge containing oxygen consuming waste. A site-specific water quality model will need
to be provided if the county wishes to continue pursuing a surface discharge. Such a model is
expected to be complex because of tidal effects and plume overlap, and require the generation
of field data for calibration and validation purposes.
While a model is required to obtain Speculative Limits, a new discharge must also submit an
Engineering Alternatives Analysis (EAA) to justify that a new discharge is the most
environmentally and economically sound option available. The Division would require that the
option to connect to another wastewater system be thoroughly examined given the facility's
existing connection to the Elizabeth City treatment plant and recommends that the county and
city develop a regional approach and solution to current and future wastewater needs. The
Division also has concerns about new discharges to existing water supply watersheds.
D - North Carolina Department of Environmental Quality 1 Division of Water Resources
,S�!/� 512 North Salisbury Street f 1617 Mail Service Center I Raleigh.North Carolina 27699 1bi7
OyuMwM q ErnovrxmoW Ow;N. 919.707.9000

Should you have any questions about these speculative limits or NPDES permitting
requirements, please feel free to contact David Hill at [e-mail] or (919) 707-
3612.
Respectfully,
ie Grzy1: per sor
ndustrial Permitting
Water Quality Permitting
Division of Water Resources
Hardcopy:
Central Files
NPDES Files
Electronic Copy:
DWR/Non-Discharge Branch/Nathaniel Thornburg
DWR/Washington Regional Office/Water Quality Regional Operations
DWR/Basinwide Planning, Ian McMillan
DWR/NPDES Server>Specs
Leo Green, [e-mail]
greeneng.com
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