WQ0001863_Annual Performance - 08-2022_20220803

Performance Report 2021/2022
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Annual Sewer and Collections System
Performance Report
The North Carolina Clean Water Act of 1999 requires the City of Mount Holly to provide an annual
report to its customers. Also to the North Carolina Department of Environment and Natural Resources
(NCDENR),to summarize the sewage treatment works and collection system's performance over the last
year.
You may Review Act at:
https://www.ncleg.net/Sessions/1999/Bills/House/PDF/H1160v4.pdf
Mount Holly Permits
NPDES Permit: NC0021156
Land Application Permit: WQ0001863
Collections System Permit: NCCS00059
Storm Water for WWTP: NCG110000 (General)
Overview
Wastewater from the City of Mount Holly Residents, Businesses, and Industries flow by gravity
through approximately 125 miles of sewer lines, through approximately 2600 manholes, to one of 17 lift
stations.The Wastewater then flows to the City of Mount Holly's Wastewater Treatment Facility where
it is then treated. When the wastewater enters the facility it is screened to remove any large debris.
After screening the wastewater flows by gravity through 2 (two million gallon) aeration basins which is
where the biological portion of the treatment occurs. In the biological process tiny microscopic bacteria
and organisms treat the wastewater and oxygen is added. After aeration the wastewater flows to two
clarifiers where the wastewater is slowed down and the biological organisms are separated from the
water by gravity.After clarification the biological organisms are sent back to the beginning of the
process and met with incoming flow, Once the Organisms have been through the process enough they
get pumped into two 750,000 gallon digesters where it is aerobically digested prior to Land Application
on farm land for the re-use of the nutrients. The treated water leaves the clarifiers and flows into two
chlorine contact basins where the water is met with chlorine for disinfection purposes. Once any
remaining bacteria has been killed by the chlorine the treated water flows through sulfur dioxide to
remove the residual chlorine prior to discharge into the Catawba River. Below is a simple diagram of the
treatment process at the City of Mount Holly Wastewater Treatment Facility.
RECEIVED 1
NCDEQ/DWR
10 AUG 2022
Wage
Non-Discharge
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Performance Report 12021/2022
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Performance Report 12021/2022
Sampling
Each year the City of Mount Holly performs over 37,000 measurements and chemical analysis
annually to comply with permit requirements,treat the wastewater and safely return it to the
environment.The City's staff of trained and certified operators are committed to the goal of providing
the wastewater customers with the most efficient, cost effective wastewater treatment. Below is a table
of the current discharge limitations and the average daily discharge from the Mount Holly Wastewater
Treatment Facility.
Monthly Weekly Daily Daily Annual Average Maximum Minimum
Average Average Maximum Minimum Limit Discharge Daily Daily
limit limit limit limit 7/1/21- Discharge Discharge
6/30/22
Flow in 4.0(MGD) 2.311 MGD
Million
Gallons per
Day(MGD)
Biochemical 30.0 mg/I 45.0 mg/I 6.11 mg/I
Oxygen
Demand
(BOD)
Total 30.0 mg/I 45.0 mg/I a 6.2 mg/I
Suspended
Solids(TSS)
Fecal 200/100m I 400/100m I 19.72/100m I
(Geometric
Mean) _
Total 50 ug/I 26.95 ug/I
Residual
Chlorine
(TRC)
Dissolved 5.0 mg/I 5.71 mg/I
Oxygen
(DO)
PH 9.0 su 6.0 su 7.7 su 6.99 su
Annual 31,405 13944 lbs
2020 Total lbs
Phosphorus
Wage

Performance Report 2,021/2022
Performance
The City of Mount Holly is committed to constantly improve our Wastewater Treatment Facility and
Collections System to protect the customers and the environment from the potential harm of
inadequately treated wastewater.
Wastewater Treatment Plant
The City of Mount Holly Wastewater Treatment Plant had (0) permit violations for the
2021/2022 fiscal year.
Wastewater Collections System
The City of Mount Holly Wastewater Collections System had 2 permit violation for the
2021/2022 fiscal year. The 1st violation occurred on 9-17-21 and lasted for approximately 1 hour
and resulted in 300 gallons reaching the ground and it was unknown if any sewer reached any
body of water. This SSO was determined to be caused by grease blockage. The 2nd violation
occurred on 5-30-22 and lasted for approximately 1.5 hours. An estimated amount of 3800
gallons of sewer was lost during this SSO event. It was determined that no sewer reached any
body of water.There was a Notice of Violation issued for the violation that occurred on 5-30-22.
At the time of this report there have been NO known adverse environmental impacts.
Public Notification / How You Can Help Protect the Environment
In the event of an overflow the City has the responsibility to repair the problem causing the overflow
and mitigate any damage.The City also has to report the spill to the State. If the spill exceeds 15,000
gallons, a public notice is issued at the time of the spill. The State can fine the City for large overflows.
Most overflows are caused by grease or obstructions in the system. You can help stop overflows by
keeping fats, oils and grease out of your drain. You can also call City Hall or the 24hr Utility Customer
Service at [phone] if you see a manhole overflowing, missing manhole cover or broken pipes.
If you have any questions concerning our Wastewater system or this report please contact the
Wastewater Treatment Facility at(704)827-4261.
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Performance Report 2021/2022
Name of Regulated Entity and Responsible Contact
Mount Holly Wastewater Treatment Plant
City Manager: Miles Braswell
P.O. Box 406
Mount Holly, NC 28120
704-827-3931
(Wastewater Treatment)
Operator in Responsible Charge: Doug Shoutd
P.O. Box 406
Mount Holly, NC 28120
704-827-4261
(Collections System)
Operator in Responsible Charge: Ronnie Hale
P.O. Box 406
Mount Holly, NC 28120
704-913-5090
Certification
I certify, to the best of my knowledge,this report is accurate and complete meeting the requirements of
the North Carolina House bill 1160, 1999 Clean Water Act, and the guidance provided by (DWQ) Division
of Water Quality Compliance and Enforcement Unit's letter of October 10, 1999.
Miles B swell, City Manager Date
This report is posted on www.mtholly.us and is available at City Hall upon request
Submit 3 copies to:
System Performance Annual Report
North Carolina Division of Environmental Quality
1617 Mail Service Center
Raleigh, NC 27699-1617
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