NC0040011_Response to Notice_20230721

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July 20a', 2023
TOWN OF YANCEYVIL_LE
INCORPORATED
"Tradition with Vision" 1986
Ms. Jennifer F. Graznak, Assistant Regional Supervisor
North Carolina Department of Environmental Quality
Division of Water Resources
450 West Hanes Mill Road, Suite 300
Winston-Salem, NC, 27105
Subject: Notice of Violation (NOV 2023-LV 0470)
Dear Ms. Graznak:
We are in receipt of your July 10t', 2023, Notice of Violation for permit exceedances at the Town
of Yanceyville Wastewater Treatment Facility during April 2023. As your July 10t' NOV
indicated, our treatment system did experience permit excursions for weekly effluent limits for
Biological Oxygen Demand (BOD), Ammonia Nitrogen and Total Suspended Solids (TSS) as
well as an effluent monthly limit for Ammonia Nitrogen. We would like to provide additional
information related to this noncompliance event. This information is presented subsequently for
your review and consideration.
Corrective measures were taken as soon as possible, and the facility has returned to compliance
with the permit limitations following the April excursions. The permit excursions experienced in
April were due to malfunctioning treatment system controls and equipment. The Yanceyville
WWTF is a Sequencing Batch Reactor (SBR) biological treatment system which is dependent on
the programable logic controls to initiate the proper operations in specific sequences of the batch
type operation of the two SBR treatment units. Failure of an effluent decanter actuator valve on
one of the SBR units resulted in the treatment system defaulting to "storm mode" operation.
This caused treatment sequencing changes which adversely affected the treatment performance
and ultimately effluent compliance. This treatment system issue corresponded with a storm event
in the area which also initially disrupted electrical service to the treatment system and
contributed to the failure of the normal treatment system performance and functions of the
treatment system controls. Once this problem was identified, staff immediately contacted Aqua
Aerobics, the equipment manufacturer, to respond to the control program issues. Aqua Aerobics
service technicians were booked out for an extended period, which has been a challenge in the
current service and supply chain market. We contacted another system control specialist to
evaluate the problem. The control specialist worked closely with the SBR manufacturer,
158 E. Church Street - P.O. Box 727 - Yanceyville, North Carolina 27379
[phone] Fax [phone] www.yanceyvillenc.gov

remotely, to troubleshoot the PLC program for this unit. Repair and replacement efforts included
replacing the system control cable, capacitor, effluent tank decanting actuator motor, float switch
and actuator motor limit switch. Please note that most of these parts are unique to this
manufacturer's equipment and were difficult to obtain quickly. In the case of the actuator motor
and limit switch mounting, it was suitable to have a part fabricated to meet our needs in a quicker
timeframe. The town and our operator's worked with multiple subcontractors as quickly as
possible to minimize the time of noncompliance and return the facility to a compliance status as
soon as possible. In addition, resources were initiated to haul "seed sludge" to establish
nitrification as soon as possible. Also, the staff mobilized additional equipment and labor to
clean any build-up of solids in the SBR effluent tank and chlorine contact chamber.
The SBR system control functions were corrected on April 14a' and the effluent actuator
decanters were fully functional on April 24a'. The effluent compliance samples collected on April
25u' demonstrated a return to compliance within this month. The following month of May 2023,
the effluent monthly averages for BOD, TSS and Ammonia Nitrogen were 6.9 mg/l, 8.6 mg/1 and
0.08 mg/l, respectively. The June 2023 monthly averages for effluent BOD, TSS and Ammonia
Nitrogen were 6.6 mg/l, 10.5 mg/l and 0.125 mg/l, respectively. As you will note, once the failed
equipment was repaired, the staff immediately brought the facility back into compliance,
including complete nitrification.
The Town of Yanceyville is committed to effective wastewater treatment compliance and
protection of the receiving stream and environment. The Town has limited financial resources
and respectfully request that your office not pursue civil penalty for this event. The Town feels it
would be more beneficial to put our funds into additional financial needs at the facility. I hope
that this information is helpful in detailing the specifics and circumstances of the event. If you
have any questions or require additional information, please advise.
Thanking you in advance for your consideration in this matter.
In solidarity,
va*yka� t_&M�
Kamara Barnett, Town Manager
cc: Inframark