NC0021491_NOV-2020-PC-0504 Response_20210106

WILLIAM J. MARKLIN, Ill
Mayor
Commissioners:
ROB TAYLOR, Mayor Pro Tem
JUSTIN DRAUGHN
ERIC SOUTHERN
AMY VAUGIIAN-JONES
13RIAN WILLIAMS
December 15, 2020
Jown o/ woc4lville
M..�,.
1979
INCORPORATED 1839
171 S. CLEMENT STREET
MOCKSVILLE, NC 27028
Mr. Lon T. Snider
Regional Supervisor
Water Quality Regional Operations
Division of Water Resources, WRSO
Subject: Notice of Violation — (NOV-2020-PC-0504)
Compliance Evaluation Inspection
Dutchman Creek W WTP
NPDES Permit Number NCO021491
Davie County
LYNN TRIVETTE
Interim Town Manager
RECEIVED
]AN 0 6 2021
NCDEQ/DWR/NPDES
Mr. Snider,
Thank you for allowing the Town of Mocksville the opportunity to respond to the Notice of
Violation dated December 4, 2020, and received on this same day. This violation details the
infractions found during the compliance evaluation inspection held at the Dutchman Creek
Wastewater Treatment Plant: conducted by Mr. Justin Henderson on November 30, 2020. Our
response to the concerns brought forward in the inspection report are as follows;
Chuck Willis of Willis Engineering is leading the ongoing Dutchman Creek WWTP Renovation
project, funded by federal loan provisions granted to the Town of Mocksville for restoration of
the plant. The project is expected to be completed before the end of 2021. Significant upgrades to
the plant are being made that will enable it to keep up with the increasing demand. Upgrades to
the headworks, clarifiers, and process pumps are underway; new solids thickening methods and a
second digester is being added. Press and haul and sludge removal efforts have been made in the
interim for solids control.
1. Regarding the historic BOD exceedances, it is our understanding that the anticipated
upgrades will help. As noted in the inspection report, the plant has had limited solids
storage and is rendered unable to treat at its current design capacity.
2. Both weirs on clarifier #1 are being decommissioned and two new ones will be added.
3. The current influent splitter box is to be decommissioned and replaced.
4. The RAS/WAS pumps are to be decommissioned and replaced. We are keeping a trash
pump in the #1 pit to help return sludge back to the #1 aeration basin.

5. The influent composite sampler was not retaining adequate temperature. The temperature
probe was promptly replaced, and ice was added temporarily. The temperature is being
checked daily until restored. A new temperature sensor was ordered the very same day.
The new sensor arrived Friday 12/11. The part will be replaced and operative as of 12/21.
There is a spare sensor in inventory.
6. Pumps #1 and #3 were returned operational since the inspection, as of 12-8-20. Pump #2
was working at the time of the inspection, however the pump failed the following day. A
bypass pump was brought on site 12-1-20. Pump #3 was repaired on 12/8. Pump #2 is
currently being repaired, anticipated completion time TBD.
7. It appears that the Division may have an inaccurate copy of the AWWPR. Please verify
that the copy the Division has on file is the same as attached.
The infrastructure deficiencies are within our awareness and are slotted for appropriate
augmentation, replacement, and/or repair accordingly. We believe the upgrades to the plant will
resolve the ongoing issues with treatment. The plant is expected to return to compliance once
construction is complete. The action items cited in this report have been duly noted. The Town of
Mocksville and Envirolink staff are working diligently to yield to the recommendations
provided. It is our request that our attention in these matters be taken into account by the
Division when proceeding with enforcement.
Sincerely,
Lynn Trivette
Town of Mocksville
CC:
Robert White, Envirolink
Joshua Powers, Envirolink

Town of Mocksville
Annual Performance Report
(January 1, 2019 —December 31, 2019)
I. General Information
Facility/System Name: Dutchman Creek Wastewater Treatment Plant
Responsible Entity: Envirolink, Inc.
Person in Charge/Contact: Chip White
Applicable Permit(s): NCO021491
We are pleased to present your Annual Wastewater Report. The Clean Water Act of 1999, passed by the
North Carolina General Assembly, requires Utilities to provide an annual report to their wastewater
customers. This report summarizes the performance of your wastewater treatment plant and collection
system over a 12-month period (January 1, 2019 - December 31, 2019)
Description of Treatment System:
0.98 MGD wastewater treatment facility with the following components:
• Flow splitter box
• Mechanical fine screenine
• Grit removal
• Flow measurement
• Three aeration basins
• Three secondary clarifiers
• Chlorination and dichlorination units
• Sludge recirculation and wasting
• Aerobic digester
• Emergency generator
This W WTP is located at 295 Garwood Road, Mocksville, NC 27028
1I. Performance
Wastewater Treatment Plant

Construction began during 2019 to complete updates to the plant, such as increasing digester volume and
clarifier volume, as well as updates to the RAS and WAS piping and pumps. In 2019, the average daily
flow that was treated at this facility was 435,172 gallons per day.
2019 Wastewater Treatment Permit Violations
Date
Permit
Results
Permit Limit
Parameter
1/5/2019
Temperature, Water
Frequency Violation
5 X week
Deg. Centigrade (OOO10)
1/19/2019
BOD, 5-Day (20 deg. C)
16.33 mg/1,
15 mg/L weekly avg
— Concentration
(CO310)
(Weekly Exceed
30nO19
BOD, 5-Day (20 Deg. C)
21.83 mg/L
15 mg/l, weekly avg
— Concentration
(CO310)
(Weekly Exceed)
3/31/2019
Nitrogen, Total —
Frequency Violation
Quarterly
Concentration (CO600)
Phosphorous,'1'otal (as
Frequency Violation
Quarterly
P) — Concentration
CO665
6/8/2019
BOD, 5-Day (20 Deg. C)
11.27 mg/L
7.5 mg/L weekly avg
— Concentration
(CO310).
(Weekly Exceed)
6/30/2019
BOD, 5-Day (20 Deg. C)
5.19 mg/L
5 mg/L monthly avg
—Concentration
(CO310)
(Monthly Exceed
727/2019
7/31/2019
BOD, 5-Day (20 Deg. C)
— Concentration
(CO310)
(Weekly Exceed)
BOD, 5-Day (20 Deg. C)
— Concentration
(CO310)
(Monthly Exceed
10.61 mg/L
6.47 mg/L
7.5 mg/L weekly avg
5 mg/L monthly avg
8/3/2019
8/32019
924/2019
BOD, 5-Day (20 Deg. C)
— Concentration
(CO310)
(Monthly Exceed)
Colifarm, Fecal Mr,
MFC Broth, 44.5 C
(31616)
BOD, 5-Day (20 Deg. C)
— Concentration
(CO310)
(Monthly Exceed
Frequency Violation
Frequency Violation
7.56 mg/L
3 X week
3 X week
7.5 mg/L weekly avg

A float in the influent lift station was hung up during a surge of inflow following a rain event. This
caused the pumps to run excessively, sending higher amounts of wastewater to the bar screens. In
addition, the rag screw at the influent lift station was inoperable due to age and wear, leading to large
amounts of rags and debris that accumulated on the bar screens. The surge of flow was backed up at the
headworks due to the rag buildup on the bar screens.
When the operator discovered the headworks overflowing at 0615 on December 16, he immediately shut
off the pumps at the influent lift station. When the flow to the headworks had ceased, he cleaned off the
bar screens at all three treatment trains. The floats in the lift station were pulled and cleaned. The lead
pump float had significant accumulation of grease and rags, which were removed from the float. Lime
was applied to the ground around treatment train #1 that had wastewater on it.
The wastewater that overflowed from treatment train #3 was contained in a ditch nearby that had been
dug for the purpose of utility installation. This ditch was pumped out and into aeration basin #3. The
areas around the #3 headworks leading to the ditch were covered in lime, as well as the ditch itself.
The Town of Mocksville approved to replace the rag screw as a part of a larger plant upgrade that was
ongoing during the 2019 period. In addition, the floats in the lift station are to be checked and cleaned
weekly under normal conditions and daily under rainy conditions to ensure that floats and pumps are
operating correctly.
III. Notification
A copy of this report has been given to the authorities of the Town of Mocksville for distribution.
IV. Certification
I certify under penalty of law that this report is complete and accurate to the best of my knowledge. I
further certify that this report has been made available to the user or customers of the named system and
that those users have been notified of its availability.
Matt 5ettlemyer
Town Manager
Date