WQCS00057_NOI_NOV2020DV0048_Response_#2_20200218

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City of Thomasville
Thomasville, North Carolina 27360
CAR�A
Lon T. Snider
Regional Supervisor
WQROS, WSRO, DWQ, NCDEQ
450 W. Hanes Mill Road, Suite 300
Winston-Salem, NC 27105
RE: Intent to Enforce Letter Response
Incident Number 201901900
Dear Mr. Snider,
NC Department of
Environmental Quality
Received
FEB 2 0 2020
Winston-Salem
Regional Office
Utilities Department
18 February 2020
In response to the letter of Intent to Enforce of 03 February 2020 the City of Thomasville asks
that the following be taken into consideration:
Regarding incident #201901900: Cleaning and video inspection of the existing Hank's Branch
outfall main line had been mostly completed as part of the Hank's Branch Phase 1 Rehabilitation when
this incident occurred. Additionally, an existing "sand trap" structure had been removed and replaced
with new PVC pipe, and CIPP lining of some segments of the main gravity outfall that leads into this
station had been completed as part of the Hank's Branch Phase 1 Rehabilitation immediately upstream
of this station. All of this work served not only to reduce infiltration, but also to reduce exfiltration from
the main Hank's Branch Outfall pipe just at the time we had a heavy rainfall event of over 1.5". It
appears that rainfall runoff entered the collection system through multiple means such as leaky pipe
joints, broken taps and cleanouts, and leaking manholes located upstream of the outfall pipe that had
been worked on. The increased volume of the main outfall for transmitting flow to the pump station
(due to the cleaning which removed a large amount of debris) combined with the better sealed system
led to reduced exfiltration of the I&I water and overwhelmed the pump station.
The volume of wastewater spilled was nominal, duration of the event was brief, much of the
water that spilled was rain water, and there were no known impacts to public health, fish kills, or
recreational area closures as a result. There is a second phase of this project planned that has been
under reviewed by DWR and DWI staff for quite some time now, delaying its eventual implementation.
Phase 2 of the Hank's Branch Outfall Rehabilitation will address several upstream sections of laterals
that discharge into the Hanks Branch main outfall that have I&I issues by a combination of pipe
replacement and CIPP lining where appropriate. It is anticipated that Hanks Branch Outfall Phase 2 will
have the desired effect of reducing I&I and thus reducing the chances of overflows and the Northside
pump station.
The City of Thomasville asks that the circumstances surrounding this event as well as the
ongoing efforts to upgrade all aspects of the sanitary sewer collection system be taken into account
with any enforcement action considered.
Sincerely, Morgan Huffman
Public Services Director
City of Thomasville
336-475-4220
CC: Kelly Craver