NC0086941_Request for Speculative Limits_20100118

MCDAVID ASSOCIATES, INC.
I N C. Engineers•Planners•Land Surveyors
CORPORATE OFFICE GOLDSBORO OFFICE
[phone]•Fax[phone] [phone]•Fax[phone]
E-mail:[e-mail] E-mail:[e-mail]
3714 N.Main Street•P.O.Drawer 49 109 E.Walnut Street•P.O.Box 1776
Farmville,NC 27828 Goldsboro,NC 27533
January 18, 2010
Mr. Gil Vinzani, P.E.
Supervisor, Eastern NPDES Unit nl 1 ©f ]\:/
Division of Water Quality D
1617 Mail Service Center JAN 2 0 2010
Raleigh, NC 27699-1617
DENR-WAT R QU•
SUBJECT: Request for Speculative Limits POINT SOURCE BRANCH
Water Treatment Plant Expansion
NPDES Permit NC 0086941
Southeastern Wayne Sanitary District
Wayne County, NC
Dear Mr. Vinzani:
Southeastern Wayne Sanitary District (SEWSD) operates a potable drinking water system in
southeastern Wayne County that serves approximately 5,000 users. A portion of its water is treated
(iron and manganese removal) via filtration at an existing .9 MGD water treatment plant (WTP) on
Arrington Bridge Road. Although the backwash from the filters is typically treated and re-used,
SEWSD maintains NPDES Permit NC 0086941 which allows the discharge of its treated backwash
water to Horsepen Branch. The NPDES Permit includes limits for suspended solids, settleable
solids, turbidity and residual chlorine. The NPDES Permit does not limit FLOW.
SEWSD is planning to increase the size of its existing WTP from .9 MGD to 1.62 MGD in
order to replace capacity loss due to Capacity Use Area rules which mandate reductions in
withdrawals from other existing wells. The quantity of wastewater will increase from 33,000 gpd
to 66,000 gpd as a result of the WTP expansion. Treatment facilities at the existing WTP will be
duplicated during the proposed expansion. No change in the quality of treated effluent is
anticipated.
SEWSD has not discharged to Horsepen Branch in recent years. In lieu of discharging, treated
wastewater is recycled through the treatment process and processed into potable water. SEWSD
maintains its NPDES Permit as a safety measure in case discharge becomes necessary.
SEWSD is requesting USDA-RD financial assistance for the WTP expansion. Clearinghouse
comments were requested for the project. Hannah Stallings, Basinwide Planning Unit and SEPA
Program, DWQ, provided a comment in response to the Clearinghouse submittal suggesting a
request for speculative limits be submitted as soon as possible. This letter is provided in
accordance with Ms. Stallings' suggestion.
\\G-PC 1\D 1005\FTL\2010 1 100118
SEWSD-DWQ-REQ-SPECULATIVE-LIMITS-WTP-GV-LTR.doc

a
• Please respond at your earliest convenience. If you have any questions, please do not hesitate
to contact me.
Sincerely,
McDAVID ASSOCIATES, INC.
F. Tyndall Lewis, P.E.
Goldsboro Office
FTL:
cc: Rich Moore
Ed Causey, USDA-RD
\\G-PC1\D1005\FTL\2010 2 8
SEWSD-DWQ-REQ-SPECULATIVE-LIMITS-WTP-GV-LTR.doc