NC0023884_permit modification_20080523

May 23, 2008
David W. Treme
City Manager
P.O. Box 479
Salisbury, NC 28145-0479
Michael F. Easley, Governor
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
Coleen H. Sullins, Director
Division of Water Quality
Subject: Monitoring for High Rock Reservoir (Permit - NC0023884)
Total Maximum Daily Load (TMDL) Study (chlorophyll a and turbidity)
Dear Mr. Treme:
The Division of Water Quality (DWQ), in partnership with the Yadkin Pee -Dee River Basin
Association (YPDRBA), has begun monitoring of the High Rock Reservoir watershed for the
purpose of chlorophyll a and turbidity TMDL development, as of April 2008. The monitoring
is scheduled to last for two years (April 1, 2008 - March 31, 2010).
Ms. Kathy Stecker, Supervisor, Modeling and TMDL Unit, discussed additional effluent
monitoring needs for NPDES dischargers at the YPDRBA meeting held October 5, 2007.
These increased nutrient and turbidity monitoring needs are not currently included in your
facility's permit effluent monitoring requirements. Members of YPDRBA have agreed to
perform the additional monitoring for the duration of the two-year study, in order to supply
sufficient data to perform a comprehensive TMDL for High Rock Lake. Although your permit
is not being reopened to include this additional monitoring, should the voluntary monitoring
falter, the Division will reconsider this decision to include the additional monitoring for the
time necessary.
The additional effluent monitoring requirements for your facility are:
Parameter Description
Parameter
Code
Measurement
Frequency
Sample Type
Sample
Location
TKN as N (mg/L)
00625
Weekly
Composite
Effluent
NO2+NO3 (mg/L)
00630
Weekly
Composite
-
Effluent
Nitrogen, Total (as N)
(mg/L)
00600
Weekly
Composite
—
Effluent
Turbidity (ntu)
00076
Weekly
Grab
Effluent
NNo e hCarolina
aturally
North Carolina Division of Water Quality 1617 Mail Service Center Raleigh, NC 27699-1617 Phone [phone]
Internet: www.ncwaterquality.org Location: 512 N. Salisbury St. Raleigh, NC 27604 Fax [phone]
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1-877-623-6748

Additional Monitoring for High Rock Lake
Page 2
Thank you for your cooperation and assistance with this monitoring effort. This data will be
invaluable to model development and improve model predictions. If you have any questions,
please contact Ms. Susan A. Wilson, ext. 510 (Supervisor, Western NPDES Program) or Ms.
Kathy Stecker , ext. 505.
Sincerely,
.Coleen H. Sullins
cc: Mooresville Regional Office / Rob Krebs
Central Files
NPDES Files
TMDL and Modeling Unit, Planning Section
Jennie Atkins, Environmental Sciences Section
Patrick Kennerly, Admin Mgr