NC0027197_Corrective Action Plan_20221122

1
NORTH AShelbvAOLINA
Post Office Box 207•Shelby,NC 28151-0207 .I 'i;i{
November 18, 2022
NCDEQ/Division of Water Resources
NPDES Compliance and Expedited Permitting
1617 Mail Service Center
Raleigh,NC 27699-1617
Certified Mail 7018 0680 0001 0376 5422 EN 5)
NCDEQ/Division of Water Resources 'L Za22
Mooresville Regional Office N�V
610 East Center Avenue, Suite 301 WRl�pp ,�
Mooresville,NC 28115 ICp�,QLD
Certified Mail 7018 0680 0001 0376 5439
RE: City of Shelby's Water Treatment Plant NPDES Permit#NC0027197
Corrective Action Plan
TO WHOM IT MAY CONCERN:
The City of Shelby's Water Treatment Plant(WTP)NPDES Permit#NC0027197 effective
November 1, 2021, Section A. (3) SCHEDULE OF COMPLIANCE (OUTFALL 001), requires a
five-year Schedule of Compliance with the Total Copper Monthly Average(7.88 ug/1) and Daily
Maximum(10.47 ug/1).
The enclosed Corrective Action Plan details corrective measures that will be followed to allow the
WTP to achieve compliance with the NPDES Permit limitations for copper within 5 years, or before
November 2026.
Please contact Brian Wilson at 704-669-6552 or [e-mail] with questions or
concerns.
Brian Wil
City of Shelby
Water Resources Operations Manager
www.cityofshelby.com

City of Shelby WTP
NPDES Permit NC000027197
Corrective Action Plan Outfall 001
City of Shelby Water Treatment Plant
Correction Action Plan
Owners Name: City of Shelby
NPDES Permit: NC0027197
Contact: Brian Wilson
Year 1 (November 1,2022)
Corrective Action: The City of Shelby identified the use of copper sulfate to treat the lagoon as the
source of increased copper discharges at outfall 001. The City has discontinued the use of copper
sulfate effective November 2022. Copper Sulfate has been replaced with Phycomycin SCP
Algaecide and Oxidizer which does not contain copper.
Status: Compliant with NPDES permit limitations for copper. A November 2022 sampling event
for copper reflected a result of 6.5 ug/1 which is compliant with the November 1, 2021,NPDES
permit limitations.
Year 2 (November 1,2023)
Corrective Action: The City of Shelby will continue to monitor monthly copper results to confirm
concentrations are remaining compliant with the current permit limitations. Should concentrations
spike or increase,the city will work with the pretreatment group to identify and isolate the new
source. Once all sources have been isolated and addressed, additional sampling will occur to ensure
compliance is maintained.
Status: Compliant with NPDES permit limitations for copper effective November 1, 2021.
Year 3 (November 1,2024)
Corrective Action: The City of Shelby will continue to monitor monthly copper results to confirm
concentrations are remaining compliant with the current permit limitations. Should concentrations
spike or increase, the city will work with the pretreatment group to identify and isolate the new
source. Once all sources have been isolated and addressed, additional sampling will occur to ensure
compliance is maintained.
Status: Compliant with NPDES permit limitations for copper effective November 1, 2021.
Year 4 (November 1,2025)
Corrective Action: The City of Shelby will continue to monitor monthly copper results to confirm
concentrations are remaining compliant with the current permit limitations. Should concentrations
spike or increase,the city will work with the pretreatment group to identify and isolate the new
source. Once all sources have been isolated and addressed, additional sampling will occur to ensure
compliance is maintained.
Status: Compliant with NPDES permit limitations for copper effective November 1, 2021.
Year 5 (November 1,2026)
Corrective Action: The City of Shelby will achieve compliance with the City of Shelby's permit
NC0027197 Total Copper Monthly Average (7.88 ug/1) and Daily Maximum(10.47 ug/1).
Status: Compliant with NPDES permit limitations for copper effective November 1, 2021.
www.cityofshelby.com