NC0026689_NOI_NOV2018LM0088_Response_20191203 (2)

TOWN OF
DENTO y
December 3, 2019
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 & INTENT TO ASSESS CIVIL PENALTY
Tracking Number: NOV-2018-LM-0088
Permit No. NCO026689
Denton WWTP
Davidson County
Dear Mr. DiMatteo:
NC Department of
Environmental Quality
j, Received
DEC 0 5 2019
Winston-Salem
Regional Office
We are writing in response to your letter dated November 18, 2019 NOTICE OF VIOLATION & INTENT TO
ACCESS CIVIL PENALTY Tracking No.: NOV-2019-LV-0860, and would like to provide justification as to
why a civil penalty of any amount would impede our efforts in rectifying the issues we are experiencing.
For some time now we have been experiencing issues in meeting the permit limit for
Dichlorobromomethane. When we began experiencing these issues we reached out to the State for
assistance. On August 24, 2017-Mr. Jim Gonsiewski visited the plant to offer assistance and gave his
recommendations for additional testing. While on site at the WWTP, we collected the additional
samples for analysis. The results, received some 10 days later, showed that the pollutant was present in
the water used for disinfection. The water entering the WWTP for disinfection of the wastewater stream
showed concentration of 14.1 ug/L. The water distribution system nor the Water Treatment Facility
are required to test for this contaminant, but are required to test for TTHM's: The distribution system
has an MCL of 60 ug/L for combined trihalomethanes.
On October 12, 2017 Mr. Eric Hudson of NCDEQ, visited the plant to give recommendations for this
issue. After reviewing data and the plant layout his recommendations were;
1. Install a''/: h.p. jet pump with a small pressurized storage tank, pressure stitch, check valve, and
back washable discharge filter, with a suction line of the pump piped into the chlorine contact
chamber approximately 2 feet below the surface.
201 W. Salisbury Street
P.O. Box 306 Phone: [phone]
Denton, NC 27239 Fax: [phone]
This institution is an equal opportunity provider and employer

u
I

2. Install a % h.p. submersible pump with a small pressurized storage tank, pressure tank, pressure
switch, check valve, and (back -washable) discharge filter, with the pump installed into the
chlorine contact chamber approximately 2 feet below the surface.
3. Install a water well on plant property.
We contacted Piedmont Chlorinator Services and showed them the recommendations given to us by Mr.
Hudson and he went to work on designing a system and ordering parts needed. The new disinfection
water feed system was placed online on March rh 2019. A Y2 h.p. centrifugal pump with an inline
strainer was installed with the suction located 4 feet below water line in Sulfur Dioxide chamber at end
of chlorine contact chamber.
Upon receipt of our May sampling, we showed the limit had been exceeded and we began a cleaning
project to find and remove organics from the waste stream. We drained and pressure washed secondary Ij
clarifiers as well as the side walls of the chlorine contact chamber. We continued to pay attention to the
cleanliness of these areas"but we still exceeded the parameter limit. Upon data'review during cold
weather months we do not have an issue, but once the water warms up above 20°C, we see the
Dichlorobromomethane levels increase.
Upon receipt of the Notice of Violation and Intent to Assess civil penalty we contacted NC Rural Water
Association for assistance. Mr. Dwight Lancaster made two recommendations,
1. Reduce chlorine feed (lbs./day) to a level where we still meet fecal coliform limits but reduce
the chlorine that can create the pollutant.
2. Install a sump pump at end of chlorine contact chamber with an aspirator installed on the
discharge of the pump. He then said that Piedmont Chlorinators had installed this type of
system at another municipality recently.
I have contacted Piedmont Chlorinators and explained what had been suggested by NC Rural Water. Eric
Howie of Piedmont Chlorinator is ordering parts needed for this aeration system. As no additional
plumbing or power is needed, this project will not take very long to implement.
As I have explained, we have continued to seek out and find solutions forthis issue. We ask that no
monetary fine be levied against the Town of Denton as any amount will impede our efforts to return to Ij
compliance. Please note that as of the writing of this letter we have returned to compliance. The results
for November 2019 were-<1.00 ug/L. -
Thank you for your consideration and attention in this matter.
Sincerely,
lr--
Troy B. Branch
Town of Denton WWTP ORC