NC0031879_NOVNOI2022LV0046_RESP_20220202

CITY OF MARION
OFFICE OF
P. O. Drawer 700 THE PUBLIC WORKS DIRECTOR
Marion, North Carolina 28752
February 2, 2022
Mr. Daniel Boss, Assistant Regional Supervisor
Water Quality Regional Operations Section, NCDWR, NCDEQ
Asheville Regional Office
2090 U.S. Hwy 70
Swannanoa, NC 28778
Subject: Notice of Violation
Tracking #: NOV-2022-LV-0046
Permit NO. NCO031879
Corpening Creek WWTP
McDowell County
Dear Mr. Boss,
I am writing in response to your letter dated January 18, 2022, and received by the City of Marion on January
24, 2022, the subject of which was a Notice of Violation and Intent to Assess Civil Penalty for BOD limit
exceedance violations on December 25, 2021 and December 31, 2021. The BOD limit exceedance violation
dated December 25, 2021 involved an exceedance of the weekly average limit for BOD. The BOD limit
exceedance violation dated December 31, 2021 involved an exceedance of the monthly average limit for BOD.
The exceedance of both averages (weekly and monthly) was caused by the high concentration (352 mg/1) of
BOD reported for December 21, 2021. WWTP personnel have reviewed all available data, but have not been
able to determine the exact cause of the high BOD result for December 21, 2021. Review of hourly flow data
did not indicate hydraulic overload and, operationally, nothing appeared abnormal. There was no indication of
a slug flow. Water temperatures did not change significantly. The BOD result for December 20, 2021 (the day
before) was 7.2 mg/l. The BOD result for December 22, 2021 (the day after) was 10.2 mg/l. As a
precautionary measure, Operators cleaned the contact chamber to prevent further violations. All solids from the
contact chamber were returned to the influent wet well during the cleaning procedure.
The City respectfully requests that a civil penalty not be assessed for the violations. As previously stated, the
exact cause of the high BOD result for December 21, 2021 is unknown and the plant processes did not appear to
be upset. Plant Personnel quickly cleaned the contact chamber to prevent further violations. If you have any
questions or require additional information, please contact me at 828-652-4224 or WWTP Superintendent Tim
Horton at 828-652-8843. Thank you in advance for your time and consideration.
Sincerely
Brant Sikes
Public Works Director
cc: Bob Boyette, City Manager
Tim Horton, WWTP Superintendent