NC0024872_correspondence_20150520

ATA....
NCDENR
North Carolina Department of Environment and Natural Resources
Pat McCrory
Governor
May 20 2015
Beth Dirks
County Manager
Davie County
123 South Main Street
Mocksville, NC 27028
Subject: Use of Method 1631 for Mercury Analysis
Program: Davie County
County: Davie
NPDES#: NC0024872
Dear Ms. Dirks:
Donald R. van der Vaart
Secretary
As you may know, in 2012 North Carolina adopted an EPA approved statewide mercury total maximum
daily load (TMDL). To demonstrate compliance with the TMDL Permittees must be able to quantify the
amount of mercury being discharged from point sources -to -the lower reporting level of the procedure.
In order to gather the appropriate data, all effluent mercury analysis must be conducted using the low
level Method 1631 E. This could be accomplished through the NPDES permit as a monitoring
requirement, but that may require more frequent sampling than what is required by the Pretreatment
monitoring plan. Therefore, if you are not already doing so, beginning July 1, 2015 any effluent analysis
for mercury must be done using EPA test Method 1631 E. You do not have to update your monitoring
plan at this time; a copy of this letter in the file will document this requirement.
Thank you for your continued cooperation with the Pretreatment Program. If you have any questions
please contact me at [phone] or via email [[e-mail]].
Sincerely,
agkr°^"L.\
Deborah Gore
PERCS Unit Supervisor
Cc: Central Files
NPDES permit file
George Smith, Winston-Salem Regional Office Pretreatment file
PERCS
1601 Mail Service Center, Raleigh, North Carolina 27699-1601
Phone: [phone]\ Internet: www.ncdenr.gov
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