NC0055786_DMR Review Record_20230726

DMR REVIEW RECORD
Winston-Salem Regional Office
Facility Name: Lexington Regional WWTP Permit Number: NCO055786
Report Period: May Prior Assessments: 0 Enforcement Factor: 1.00
Waterbody
Outfall # Outfall Description Waterbody Name Classification
EC1 e. coli study 2023 Abbotts Creek Arm of High Rock Lake WS-V,B
001 Effluent to Abbotts Creek Abbotts Creek Arm of High Rock Lake WS-V,B
Monthly Average Limit Violations
Sample Location: Outfall 001- Effluent
Violation Unit of Limit Calculated % Over
Date Parameter Frequency Measure Value Value Limit Action
5/31/2023 BOD, 5-Day (20 Deg. C) - 5 X week mg/I 5 7.60 51.8 Proceed to NOI
Concentration
5/31/2023 Nitrogen, Ammonia Total (as N) - 5 X week mg/I 1 1.90 88.0 Proceed to NOI
Concentration
Weekly Average Limit Violations
Sample Location: Outfall 001- Effluent
Violation Unit of Limit Calculated % Over
Date Parameter Frequency Measure Value Value Limit Action
5/13/2023 BOD, 5-Day (20 Deg. C) - 5 X week mg/I 7.50 13.40 78.7 Proceed to NOI
Concentration
5/20/2023 BOD, 5-Day (20 Deg. C) - 5 X week mg/I 7.50 11.70 56.1 Proceed to NOI
Concentration
5/13/2023 Nitrogen, Ammonia Total (as N) - 5 X week mg/I 3 4.30 44.7 Proceed to NOI
Concentration
Other Violations/Staff Remarks:
County: Davidson
MAF: 2.426667 MGD
Reported as: Compliant
eDMR Comments: "BOD/Ammonia, we have had some spikes in both and believe this is due to our polishing ponds, we have
since cleaned a lot of algae from the spill ways and weirs in the ponds as well as the effluent weir, we are aerating the ponds and
have effluent blowers on and are chlorinating the ponds, this seems to be combatting the problem at this time. This is after I had
contacted the regional office on 5/16/23 with a heads up, we are still trying to figure this out and any help/advice would be greatly
appreciated."
JSB Remarks: Recurring BOD and ammonia exceedances since March 2023. Issued NOI for April 2023. ORC has made timely
reports to DWR WSRO of all upsets and exceedances. ORC has requested a technical assistance visit.

JSB Recommendation: NOI
Supervisor Remarks:
Lon NOI
NOV-2023-LV-0513
Completed by: Jesse Barnes
Assistant Regional
Supervisor Sign -off:
Regional
Supervisor Sign -off: LTS
Date: 7/25/2023
Date:
Date: 7/26/2023

Prior 12-Month Enforcement Histor
Permit Number: NCO055786
Report Period: May
Limit Violation
Sample Location:
Outfall 001 - Effluent
Violation
Report
Violation
Date
Period
Parameter
Type
NOD NOV CPA
10/8/2022
10-2022
BOD, 5-Day (20 Deg. C) -
Weekly Average
NOV-2022-LV-0904
Concentration
Exceeded
3/18/2023
3-2023
BOD, 5-Day (20 Deg. C) -
Weekly Average
NOV-2023-LV-0348
Concentration
Exceeded
3/31/2023
3-2023
Nitrogen, Ammonia Total (as
Monthly Average
NOV-2023-LV-0348
N) - Concentration
Exceeded
4/1/2023
4-2023
BOD, 5-Day (20 Deg. C) -
Weekly Average
NOV-2023-LV-0471
Concentration
Exceeded
4/8/2023
4-2023
BOD, 5-Day (20 Deg. C) -
Weekly Average
NOV-2023-LV-0471
Concentration
Exceeded
4/29/2023
4-2023
BOD, 5-Day (20 Deg. C) -
Weekly Average
NOV-2023-LV-0471
Concentration
Exceeded
4/29/2023
4-2023
Nitrogen, Ammonia Total (as
Weekly Average
NOV-2023-LV-0471
N) - Concentration
Exceeded
4/30/2023
4-2023
BOD, 5-Day (20 Deg. C) -
Monthly Average
NOV-2023-LV-0471
Concentration
Exceeded
4/30/2023
4-2023
Nitrogen, Ammonia Total (as
Monthly Average
NOV-2023-LV-0471
N) - Concentration
Exceeded
5/28/2022
5-2022
BOD, 5-Day (20 Deg. C) -
Weekly Average
NOV-2022-LV-0471
Concentration
Exceeded
5/28/2022
5-2022
Nitrogen, Ammonia Total (as
Weekly Average
NOV-2022-LV-0471
N) - Concentration
Exceeded
5/31/2022
5-2022
BOD, 5-Day (20 Deg. C) -
Monthly Average
NOV-2022-LV-0471
Concentration
Exceeded
5/31/2022
5-2022
Nitrogen, Ammonia Total (as
Monthly Average
NOV-2022-LV-0471
N) - Concentration
Exceeded
6/30/2022
6-2022
BOD, 5-Day (20 Deg. C) -
Monthly Average
NOD-2022-LV-0112
Concentration
Exceeded
8/31/2022
8-2022
Nitrogen, Ammonia Total (as
Monthly Average
NOV-2022-LV-0795
N) - Concentration
Exceeded
9/30/2022
9-2022
Nitrogen, Ammonia Total (as
Monthly Average
NOV-2022-LV-0871
N) - Concentration
Exceeded