WQCS00055_NOV-2020-DV-0368 Response_20200908

NEN° City of Henderson
o� Public Works Department
moo"� Post Office Box 1434 •900 S. Beckford Drive
Henderson, NC 27536-1434
Phone: [phone] Fax: [phone]
September 8, 2020
NC Dept of Environmental. Quality
Mr. Scott Vinson, Regional Supervisor
Water Quality Regional Operations Section SEP 16 2020
Raleigh Regional Office
Division of Water Resources, NCDEQ
1628 Mail Service Center Raleigh Regional Office
Raleigh, NC 27699-1628
Re: Response to Notice of Violation & Intent to Issue Civil Penalty
Tracking No. — NOV-2020-DV-0368
Sanitary Sewer Overflows —July 2020
Henderson Collection System
Permit No. — WQCS00055
Dear Mr. Vinson:
I am writing in response to the above mentioned violation that we received on August 26, 2020. The spill
in incident 202002254 at the Sandy Creek Pump Station was due to a failure on the battery backup for
the PLC and SCADA system.
We received a call on July 30 that the alarm was going off at the Sandy Creek Pump Station. Henderson
Water Reclamation Crews responded to find the PLC and SCADA systems had shut down due to a failure
in the battery backup. Crews rebooted the battery backup, immediately putting the station back to
normal operation and stopping the SSO.
All debris and contaminated dirt was removed and lime was placed on the affected area. Oxygen levels
were taken upstream and downstream from the spill. The DO levels were not low enough to feed
chemicals into the creek.
After the SSO we had Lord and Company, the SCADA provider, evaluate the battery backup to figure out
why it failed. They concluded that the power supply and the batteries needed to be replaced. We
replaced the batteries and the power supply. We also installed a Watchdog timer as a redundant backup
to notify the plant when the PLC is running on the backup battery.
Thank you very much for the opportunity to respond. We take our responsibility to maintain compliance
for our collection system very seriously. I trust that you find the City's actions for compliance are
satisfactory. Please feel free to contact our staff or myself should you need any further information.
Sincerely,
�- 0.( -
Lee Owen
Assistant Public Works Director

A
Attachments: HWRF Field Parameter Data Sheet
CC: Edward Terrell Blackmon, City Manager
Andy Perkinson, Public Works Director
Joey Long, Distribution & Collection System Supervisor— Collection System ORC
Christy Lipscomb, KLRWP Director/ORC, HWRF ORC
Teddy Felts, Chief Plant Operator
File

City of Henderson WRF/ Field Parameter Data Sheet
Page 1 of 1
Date 7130120 Analyst(s) DJ. SD. EC
Signature (s)
Location
Time
Conductivity
(US/cm)
DO mg1L
pH (SU)
Temp C°
Comment
SandX Creek PS Upstream
1616
5.8
Sandy Creek PS Downstream 1
1620
1.8
Sandy Creek PS Downstream 2
1622
3.2
Sandy Creek PS Downstream 3
1624
1.7
J IPUBLIC WORKSl06_PW_UTILITIE:SID1_Sewer102_SSOINOVt20201NOV-2020-DV-03681HWRF Field Parameter Data Sheet