WQCS00312_NOI_NOV2021DV0041_Response_20210210 (7)

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NC Department of
Environmental Quality
Received
MAR 0 4 2021
Winston-Salem
Regional Office
March 02, 2021
Lon T. Snider, Regional Supervisor
North Carolina Department of Environmental Quality
Division of Water Resources
Winston-Salem Regional Office
450 West Hanes Mill Road, Suite 300
Winston Salem, NC 27105
Subject: NOTICE OF VIOLATION
Tracking No. NOV- 2021-DV-0142
Sanitary Sewer Overflows — November 2020
City of Trinity
Permit No: WQCS00363
Incident # 202003357 4337 Forest Manor Drive: Pipe Failure (Break): 11/20/2020
Incident # 202003370 6332 Twinwood Court: Inflow and Infiltration, Severe Natural Condition
Dear Mr. Snider,
Thank you for the opportunity to provide evidence and justification for the violations listed above
against the City of Trinity, and we respectfully request that our evidence and justifications be considered
as a waiver of penalty against the City.
Incident# 202003357 near 4337 Forest Manor Drive: During the timeline of this event, the City of
Trinity was closed the prior week as well as the week this event occurred due to COVID exposure to
employees, quarantine timelines, and positive cases within the office. The Public Works Superintendent
was not working due to additional illness over and above the COVID quarantine.
The force main pipe that failed was installed in 2007 and went into service in 2008 following
construction of the Phase 2 Sewer Improvements project. We have had no problems with this force
main since installation until this event occurred.
Listed below is the timeline for this event and the steps that were taken by the City to correct and repair
this problem. As outlined below, City staff acted as promptly as reasonably possible to correct this
problem once we received the complaint.
5978 NC Highway 62 9 P.O. Box 50 • Trinity, NC 27370 • Phone [phone] • Fax [phone]

November 24, 2020
Time Complaint was identified and Reported: Due to City Office closure for COVID, telephone service
was routed to the City Manager's cell phone around 11:00 a.m. Once the switch was made, the City
Manager was able to check messages left on the office telephone as well as answer any incoming calls.
No message was routed to the on -call number regarding this incident but rather left on the regular
office voice mail at 8:11 a.m. on November 24, 2020. Upon review of messages, this complaint was
recorded by the City Manager via telephone call log, and contact was made by the City Manager at
11:13 a.m. to Rodney Johnson, Public Works Superintendent, to advise him of the complaint concerning
a sewer odor located near4337 Forest Manor Drive.
Mr. Johnson immediately called the on -call employee and asked that he investigate the complaint, since
Mr. Johnson was -unable to visit the complaint site due to his health issues. -
After the on -call employee made his way to the site, he found that there was a sewer leak in the force
main and called Mr. Johnson, PW Superintendent, to advise him of the same.
Contractor and Pumping Company Contacted: After being advised of the leak, Mr. Johnson
immediately secured a contractor at 12:00 p.m. on November 24, 2020 to assess the leak and make
repairs. He advised the on -call employee, who was. still at the location to turn the pumps off at the
Twinwood Pump Station and allow sewer to back up in the wet well.. When the contractor arrived, the
pumps were turned back on to allow the contractor to identify,the area of the leak for repair, and once
identified by the contractor, the pumps were immediately turned off.
Pumping Company: A 3000-gallon pump truck was requested to pump and keep the Twinwood Pump
Station wet well maintained at a safe level to prevent further spills. The truck started pumping at 6:00
p.m. on 11/24/2020 and continued to pump the wet well until 11/25/2020 at 2:30 p.m. A total of 25
loads were pumped and removed from the Twinwood Pump Station wet well. City employees were
stationed at the site from the investigation time at 12:00 p.m. on November 24, 2020 throughout the
repair and pumping time on November 25, 2020 at 2:30 p.m.
Notification to Mr. Ron Boone, Water Quality Section- Winston Salem District: Mr. Johnson made
notification to Mr. Ron Boone at 1:58 p.m., November 24, 2020 to advise him of the spill and to estimate
the amount of the spill. -During the conversation; Mr. -Johnson explained to Mr. Boone that he was ill
and had been for several days prior to November 24, 2020. He was out of the office and did not have
access to his computer. However, at the same time he received the call from the City Manager, he did
get online to review pump run times from the Mission SCADA system, and identified variances on the
SCADA System. The City is willing to share SCADA data if necessary.
November 25, 2020
Cause of Break identified by Contractor: The contractor determined that the break was caused due to
the force main pipe being originally installed on a jagged rock, and vibration in the pipe over time likely
caused the rock to wear a weak spot in the pipe that finally failed.
5978 NC Highway 62 9 P.O. Box 50 • Trinity, NC 27370 9 Phone [phone] • Fax [phone]

Repairs Completed: The existing 8" sewer force main was located and excavated, the leak was located
and verified with a pump running at Twinwood Pump Station, the damaged section of 8" force main
pipe was saw -cut and removed, one section of 8" C-900 PVC was installed and sleeved back to the
existing pipe with two (2) 8" Hymax couplings, and the excavation was backfilled with acceptable soil
and graded to provide positive drainage.
5978 NC Highway 62 • P.O. Box 50 • Trinity, NC 27370 • Phone [phone] • Fax [phone]

Incident# 202003370 near 6332 Twinwood Court: On 11/12/2020, heavy rainfall in Trinity led to
localized flash flooding. Inflow and infiltration to the sewer system in this area caused the pipe system
flowing to the Twinwood Pump Station to surcharge, and the manhole just outside the pump station
overflowed. As the heavy rainfall tapered off, heavy flows in the gravity system subsided and the
manhole stopped overflowing. After the manhole ceased overflowing, lime was spread out on top of
the ground to help neutralize the spill area.
The City had a Sewer Study performed to evaluate potential improvements to certain components of
the sewer system. The City currently has a consultant working to design improvements to the
Steeplegate Pump Station and force main which will increase its pumping capacity. Once the
Steeplegate Pump Station has more pumping capacity, the VFD's at the Twinwood Pump Station can be
sped up to increase its pumping capacity. This should allow the Twinwood Pump Station to better
handle short-term heavy flows coming from infiltration and inflow in the gravity system. City staff
periodically look for sources of infiltration and inflow to reduce and/or eliminate these flows where
discovered.
Sincerely,
:
Debbie Hinson, City Manager
City of Trinity
5978 NC Highway 62 • P.O. Box 50 9 Trinity, NC 27370 • Phone [phone] Fax [phone]