NC0021474_Annual Report_20220901

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August 25, 2022
RECEIVED
NC DEQ/DWR SEP 0 Z 2022
Water Quality Section
1617 Mail Service Center NCDEQ/DWRINPDES'
Raleigh,NC 27699-1617
Attn: System Performance Annual Report
Dear Sir/Madam:
Please find enclosed three(3)copies of the City of Mebane's 2011-2022 Annual Wastewater
Treatment and Collection System Report.A public notice has been sent to the local newspaper to
be posted directing the public to the locations of the annual report. The report will be made
available to the public at City Hall,the Public Works Department, and at the Wastewater
Treatment Plant. The report will also be available on the City's website
https://c ityofinebanenc.gov/departments/water-resource-recovery-facility/.
If you have any questions or need additional information,please contact the undersigned at (336-
906-5583, [e-mail]).
Sincerely,
P �57/444,
Dennis Hodge
Water Resource Director
CITY OF MEBANE 106 E.Washington St.I Mebane,NC 27302 0 919 304 9217 0 919 563 6144 0 [e-mail]
CITY MEBANE . com

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City of Mebane
1 Wastewater Collection and
Treatment Facility
For the Fiscal Year July 1 , 2021 — June 30, 2022

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City of Mebane
Wastewater Collection and Treatment Facility
For the Fiscal Year July 1, 2021 — June 30, 2022
Introduction
This report is produced in compliance with House Bill 1160 passed by the General Assembly of the State of
North Carolina requiring that all entities that own or operate wastewater collection and treatment systems make
an Annual Report available to their customers.This report must include information regarding how well the
system operated,what violations occurred,and other pertinent information.This report complies with these
requirements.
The City of Mebane operates a wastewater treatment facility and a sewage collection system that collects and
transports the sewage to the facility.
Following are the professionals designated by the state as the"Operator in Responsible Charge"(ORC)of the
respective systems and permits for the systems:
City of Mebane Wastewater Treatment Facility
635 Corregidor Road
Phone[phone]
NPDES Permit No. NC0021474
Operator in Responsible Charge(ORC)—Dennis J. Hodge
Mebane Public Utilities
Sewage Collection System
636 Corregidor Road
Phone[phone]
Collection System Permit No. WQCS00081
Operator in Responsible Charge(ORC)—Greg Barts
We certify under penalty of law that this report is complete and accurate to the best of our knowledge.Copies
will be available at the Wastewater Treatment Plant,the Public Works Building,the Glendel Stephenson
Municipal Building,and on the City of Mebane website at https://cityofinebanenc.gov/departments/water-
reso urce-recovery-facility/.

City of Mebane Annual Report-Page 2
System Overview
Every day an average of over 1.6 million gallons of sewage is generated in our homes,commercial
establishments,and industries that must be collected,transported,and treated to very stringent standards before
it is released back into our environment through our waterways.This service is provided by the City and is
funded almost entirely from the user charges that are paid monthly by our customers.
The sewage collection and wastewater treatment facility of the City of Mebane begins with over 6,002
connections that serve homes,commercial establishments,and industries.Nearly all of the sewage or
wastewater that is generated by customers flows by gravity through sewers that range from 6 to 16 inches in
diameter. Mebane operates 123.64 miles of these gravity sewer lines. During this reporting period,
approximately 12.62 miles of these lines were cleaned.
As the lines leave neighborhoods,they increase in size to accommodate the flows that are collected from the
many areas that are served.These sewers generally follow terrain to take advantage of gravity flow but at certain
points pumping stations are used to transfer the flow to different basins. The City currently operates 21
pumping stations that range in capacity from 13 to 2000 gallons per minute.
The purpose of the collection system is to transport the wastewater to the wastewater treatment facility so it can
be processed and returned to our waterways with minimal environmental impact.The wastewater treatment
facility is permitted to process up to 2.5 million gallons of wastewater per day.
The wastewater treatment facility is complex,using physical,chemical,and biological processes to treat the
wastewater. The wastewater is screened to remove large,suspended materials,but the heart of the plant is a
biological process that uses bacterial cultures to remove most of the suspended and dissolved wastes that are
produced within the City.This biological,activated sludge process is sensitive to temperature,high flows
produced by rainfall leaking into sewers,and toxic discharges that can be produced by industries or even homes.
This sensitivity makes the wastewater facility susceptible to process upsets that can result in exceeding
limitations permitted by regulatory authorities.
The permitting of treated wastewater discharges is based on a"7Q 10"stream flow,or the lowest seven-day
stream flow expected every ten years.However,permit limits that are issued to protect the stream at low flow
(less assimilation),apply 24 hours per day and 365 days per year. Since Mebane's limits are calculated for
discharging to a small stream,our limitations are extremely stringent.North Carolina has some of the most
stringent stream standards in the country.Mebane WWTP discharge constitutes over 90%of the stream at the
lowest stream-flows. However,when periods of rain create high stream flows and make treatment plant
operations difficult,the treatment facility must continue to be compliant with dry weather limitations.
The City of Mebane's treatment plant operates under a National Pollutant Discharge Elimination System
(NPDES)permit.The NPDES permit includes monitoring requirements and discharge limitations,some of
which vary with seasons and have different maximums for daily values,weekly averages,monthly averages,and
quarterly averages. Some limitations protect streams from oxygen depletion, such as biochemical oxygen
demand(BOD)and ammonia-nitrogen(which exerts oxygen demand over a delayed yet prolonged basis). Some
standards/limitations are to protect aquatic life in the receiving stream,such as metals like cadmium or mercury
or other pollutants like fluoride or chlorine. Since aquatic life is more sensitive than humans to some pollutants,
some standards are as low as 12 parts per trillion* and,in many cases,are lower than drinking water standards.
*To help comprehend how small one part per trillion is: One part per trillion corresponds to one
minute in 2,000,000 years, or a single penny in$10,000,000,000.