NC0024252_Correspondence_20181211

ROY COOPER
Coverrtor
MICHAEL S. REGAN
Secretary
LINDA CULPEPPER
Director
NORTH CAROLINA
Environmental Quality
December 11, 2018
Mr. Michael Fox
Wastewater Treatment and Collection Supervisor
City of Conover
PO Box 549
Conover, North Carolina 28613
Subject: NPDES Permit NCO024252
Schedule of Compliance Annual Report
Dear Mr. Fox,
The Division received your Compliance Schedule report for total copper for the City of
Conover's Northeast Wastewater Treatment Plant (NEWWTP) as required by the NPDES permit
Special Condition A. (6) Compliance Schedule for Total Copper. The City of Conover has
evaluated copper sampling data from the previous 5 years and concluded that the rises in copper
are intermittent and lack a clear pattern. As a Corrective Action Plan (CAP) the City proposes to
increase the copper monitoring frequency and strategically set up samplers in areas in their
collection system to identify possible areas where the spikes are occurring only in the event of
another copper limit exceedance. These areas would then be investigated in order to identify
users and inspections conducted to seek the sources of an elevated copper discharge. Once the
sources are identified, the City of Conover would take action to eliminate excessive copper
discharges.
While a CAP is usually something pursued prior to an exceedance for the purpose of preventing
another exceedance, as a facility that receives 100 % domestic wastewater and no wastewaters
from Significant Industrial Users this approach is understandable. However, it is the City's
responsibility to achieve and maintain compliance with the copper limit in their NPDES permit
by November 30, 2021. Therefore, should intermittent fluctuations in copper concentrations
occur over the next several years, the Division would recommend that the strategy outlined
above be taken, whether or not an exceedance occurs. The point being that the City should strive
to achieve a consistent copper discharge at a level in compliance with the limit before the
compliance deadline.
If you have any questions regarding this matter, please contact Nicholas Coco at 919-707-3609
or nick.coco(&,,ncdenr.gov.
Sincerely,
Nicholas Coco
NPDES Complex Permitting Branch
North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 11617Mall Service Center I Raleigh, North Carolina 276"-1617
919.707.36t)1