NC0085359_Approval_20190623

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ROY COOPER I 70" I;
Governor l �4.
MICHAEL S.REGAN ;� -.. R�r a F
Secretary • 0. ""
LINDA CULPEPPER NORTH CAROLINA
Director Environmental Quality
June 23, 2019
Crystal Outlaw Panico, P.E., New Development Program Manager
Union County Public Works
500 N. Main Street,Suite#500
Monroe, NC 28112
Subject: Twelve Mile(NC0085359) &Crooked Creek WWTP (NC0069841)
Revised Residential Flow Reduction Approval
Union County
Dear Ms. Panico:
On March 29, 2019,the Division of Water Resources(Division) received a revision request for the
previously approved adjusted daily sewage flow rate (flow reduction)that would apply to all permitted
but not yet tributary residential connections and all future residential connections within the Twelve
Mile WWTP and Crooked Creek WWTP service areas.
In accordance with 15A NCAC 02T.0114(f)(2),the Division has evaluated the revision request as well as
additional information received on June 19,2019, and based on the data submitted and the Division of
Water and Infrastructure (DWI)guidance,the Division hereby approves for use by Union County Public
Works a revised adjusted daily sewage design flow rate with the following conditions:
• The flow reduction is applicable to residential single family dwellings only.
• The minimum flow for 1 and 2 bedroom dwellings shall be 140 gallons per day.
• Each additional bedroom above two bedrooms shall increase the volume by 70 gallons per day
per bedroom.
• This flow reduction shall not apply to sewer extension applications and/or permits for any other
public or private organizations whose wastewater flows are or might become tributary to the
Union County collection system (WQCS00054).
• For permitting purposes,allocations may be permitted utilizing a flow of 280 gallons per day
per lot based on a service-area average of 4 bedrooms per lot. If a residential development is
anticipated to have a limited number of bedrooms OR is anticipated to exceed an average of
4-bedrooms per lot, permitted flows shall be calculated based on the per-bedroom reduction.
o . Union County shall evaluate the average number of bedrooms per lot on an annual basis
and shall submit this information to the PERCS Unit by June 30th annually.Should the
average number of bedrooms constructed during the preceding calendar year exceed
the average of 4 bedrooms per lot,this approval must be reevaluated by the State prior
to continuing to use the approved permitting allocation of 280 gallons per lot.
D E
�,.,_ North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 11617 Mail Service Center I Raleigh,North Carolina 27699-1617
NORTH CAROLINA
Deptutmeirt o+EmIroomcatal /°" 919.707.9000

Union County
NC0085359& NC0069841
Future sewer extension applications should be made using the flow reduction amount stated above. All
other aspects of the permitting process remain unchanged,and all applications must be in compliance
with the statues, rules, regulations and minimum design criteria as certified by the owner and engineer.
Regardless of the adjusted design daily wastewater flow rate, at no time shall the wastewater flows
exceed the effluent limits defined in the NPDES Permit for the treatment facility or exceed the capacity
of the sewers downstream of any new sewer extension or service connection(s).
The granting of this flow reduction does not prohibit the Division from reopening, revoking, reissuing
and/or modifying the flow reduction as allowed by the laws, rules,and regulations contained in 15A
NCAC 02T, NCGS 143-215.1, or as needed to address changes in State and/or Federal regulations with
respect to wastewater collection systems, protection of surface waters and/or wastewater treatment.
If you have any questions, please contact Christyn Fertenbaugh, P.E., at(919)707-3625,or via email at
[e-mail].
Sincerely,
mot.
----403-1-P____
for Linda Culpepper
Director, Division of Water Resources
by Deborah Gore,Supervisor
Pretreatment, Emergency Response and Collection Systems Branch
Cc: Mooresville Regional Office,Water Quality Regional Operations
Twelve Mile(NC0085359)and Crooked Creek(NC0069841)
PERCS(electronic copy)
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