NC0026051_IWS Review_20210505

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ROY COOPER
Governor
DIONNE DELLI-GATTI
Secretary
S. DANIEL SMITH
Director
NORTH CAROLINA
Environmental Quality
5/5/2021
Durham County
Attn: Amy Moore, Laboratory & Compliance Manager
5926 NC Highway 55 East
Durham, NC 27713
Transmitted via email to [e-mail]
Subject: Pretreatment Review of Industrial Waste Survey (IWS)
Program: Durham County
WWTP: Durham County Triangle WWTP - NPDES Number NC0026051, 12 MGD
Durham County
Dear Amy Moore,
The Municipal Unit of the Division of Water Resources has reviewed the IWS for Durham County. The
IWS was received by the Division on March 31, 2021. Proper completion of an IWS is required by Durham
County Triangle WWTP's NPDES permit. The review indicates that the IWS is adequate and meets the
requirements of 40 CFR 403.8 (f) (2).
The Durham County's IWS included 538 commercial establishments/industries that contribute about 4.2
MGD of process or non -domestic flow. The County has 13 Significant Industrial Users (SIUs), 34
industries under Local Permits, and 18 industries under Biosafety Level Permits.
Please remember it is the responsibility of the POTW to continue efforts to ensure that any SIU, as defined
by NCAC 15A 2H .0903(b)(30) (A) through (D), are identified and subsequently added to the Durham
County pretreatment program. This includes evaluation of new IUs before they commence discharge and
evaluation of existing IUs determined to be not SIUs that make changes to their process.
Next IWS Due Date: May 4, 2026 unless conditions at the POTW change significantly and thus warrant an
earlier submittal. Furthermore, within 180 days of the effective date of any reissued/modified NPDES
permit, the Permittee would be required to submit to the Division a written technical evaluation of the need
to revise local limits (i.e., an updated IWS, or documentation of why one is not needed). This action may
include revising, updating, or adding to the list of SIUs. Pursuant to 15A NCAC 02H .0907(b) either the
Division or the permittee may initiate pretreatment program revisions.
Thank you for your continued cooperation with the Pretreatment Program. If you have any questions or
comments, please contact Diana Yitbarek at 919 707-9130/di [e-mail], or the Unit
Supervisor, Michael Montebello, at 919 707-3624/[e-mail].
Sincerely,
ADoclu.Signed byy:A A' •k'a.'' `
C464531431644FE...
for S. Daniel Smith, Director
Division of Water Resources
dy/ durhamcounty_iws_05_2021
Ec: Raleigh Regional Office, Cheng Zhang
Municipal Unit File and Central Files (Laserfische)
NORTH CAROLINA
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Department of Environmental ouar�
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
919.707.9000