NC0020184_DMR Review Record_20220606

DMR REVIEW RECORD
Mooresville Regional Office
Facility Name: Long Creek WWTP Permit Number: NC0020184
Report Period: April 2022
Prior Assessments: 0 Enforcement Factor: 1.00
Waterbody
Outfall # Outfall Description Waterbody Name Classification
001 Effluent to the S Fork Catawba River South Fork Catawba River WS-V
Monthly Average Limit Violations
Sample Location: Outfall 001 - Effluent
Violation Unit of Limit Calculated % Over
Date Parameter Frequency Measure Value Value Limit Action
4/30/2022 BOD, 5-Day (20 Deg. C) -
Concentration
5 X week mg/I 5 7.80 56.7
Weekly Average Limit Violations
Sample Location: Outfall 001- Effluent
Violation Unit of Limit Calculated % Over
Date Parameter
Frequency Measure Value Value Limit
Action
4/2/2022 BOD, 5-Day (20 Deg. C) -
Concentration
5 X week mg/I 7.50 10.50 40.4
4/9/2022 BOD, 5-Day (20 Deg. C) -
Concentration
5 X week mg/I 7.50 9.60 27.7
4/23/2022 BOD, 5-Day (20 Deg. C) -
Concentration
5 X week mg/I 7.50 9.40 25.1
Other Violations/Staff Remarks:
ORC indicated "As reported to the DEQ Mooresville Regional Office, a chemical spill from one of Long Creek WWTP's industrial
customers (Owens Corning) greatly impacted the plant's performance and resulted in elevated BOD levels in the effluent. On the
morning of March 25th the slug was noted at Long Creek WWTP. The influent contained a large amount of globular white solids
which then spread throughout the treatment process. Hundreds of additional samples were performed throughout the treatment
processes in an attempt to understand and mitigate the effects. At the same time, extensive efforts were made to identify the
source including trunkline sampling as well as contacting and visiting industrial customers. Process changes were implemented at
the treatment plant including increased activated sludge wasting and significantly higher feed of aluminum sulfate. The influent
returned to normal within 24 hours, but the treatment process was affected for several weeks as the material was slowly wasted
out of the return sludge. On Wednesday 3/31/2022, Owens Corning admitted to having an earlier spill of 6,000 gallons of impreg
solution, which is believed to be the source of this slug event. The impreg solution is sprayed to seal and weatherproof the thin
fiberglass sheets produced at the facility. Owens Corning staff had been unaware that a pipe in their plant had clogged, which
caused the excess impreg solution to be discharged to the POTW instead of being recycled within their process. The impreg
solution has a very high COD and affects how particles bind together. It does not contain significant quantities of heavy metals or
other toxins and small quantities are normally accepted as part of the industry's regular discharge. The City of Gastonia is
enforcing a notice of violation and significant civil penalty assessment against Owens Corning for failure to properly contain this
material and failure to properly notify the City. Since Long Creek WWTP's stringent effluent BOD limits of 5.0 mg/L monthly
average and 7.5 mg/L weekly average are in effect from April to October, no violations occurred in March. While the effluent total
suspended solids for Long Creek WWTP effluent was also elevated, it remained well below permit limits. Once this material was
wasted out of the system, BOD and TSS levels have returned to close to normal. The City of Gastonia respectfully requests that
NCDEQ not issue an NOV for the BOD violations as they were caused by an industrial slug load and the City is issuing an NOV

and civil penalty to the responsible industrial customer." Based on the facility efforts and the compliance history NOV is
recommended
Supervisor Remarks:
OK, proceed as NOV. we can review their response to make sure they have addressed the violation through
their pretreatment ordinance.
Completed by:
Assistant Regional
Supervisor Sign -off:
Regional
Supervisor Sign -off:
Ori Tuvia
DocuSigned by:
A14CC681AF27425...
Date:
Date:
Date:
6/2/2022
6/6/2022

Prior 12-Month Enforcement History
Permit Number: NC0020184 Report Period: April 2022
Limit Violation
Sample Location: Outfall 001 - Effluent
Violation Report Violation
Date Period Parameter Type
NOD
NOV CPA
7/17/2021 7-2021 BOD, 5-Day (20 Deg. C) -
Concentration
Weekly Average
Exceeded
NOD-2021-LV-0155