WQCS00073_NOV-2020-DV-0028 Response_20200303

N
north Carolina
u
city of clunn
POST OFFICE BOX 1065 • DUNN, NORTH CAROLINA 28335
[phone] • FAX [phone]
www.dann-nc.org
Janauary 27, 2020
Trent Allen, Regional Supervisor
Water Quality Regional Operations Section
Fayetteville Regional Office
Division of Water Resources, NCDEQ
225 Green Street — Suite 714
Fayetteville, NC 28301-5043
RE: NOTICE OF VIOLATION & INTENT TO ISSUE CIVIL PENALTY
TRACKING NO.: NOV-2020-DV-0028
Sanitary Sewer Overflows — December 2019
Collection System Permit No. WQCS00073
Dunn Collection System
Harnett County
Dear Mr. Allen,
Mayor
William P. Elmore Jr.
Mayor Pro Tent
ChuckTung
Council Members
J. Wesley Sills
April L. Gaulden
Frank McLean
Billy Tart
Dr. David L. Bradham
City Manager
Steven Neuschafer
The City of Dunn appreciates the opportunity to respond to the Notice of Violation
dated January 13, 2020, for a Sanitary Sewer Overflows (SSO) incident # 201901913 that
occurred on December 14, 2019. It is our intent that this response will provide
sufficient additional information regarding the incident and that the Division will
decide not to pursue further enforcement action.
Cause of non-compliance:
During the month of December, the City of Dunn measured 4.27 inches of rainfall with
2.6 inches falling on December 13th. The severe natural conditions caused the Dunn
Wastewater Collections System to become enudated with flow which led to the
570,000 gallon sewer overflow at Manhole #BR8 on the Black River Outfall line. In the
past, when there were heavy rainfall events, the collection system flows would spike
but would quickly recover and return to normal conditions after a couple of days.

After Hurricane Florence, the City of Dunn has not seen the flows return to "normal".
Even with drier conditions during the month of May and June 2019, the average dry
weather flows have increased from 1.5 MGD to 2.0 MGD. Average flows increased
from 1.8 MGD to 3.0 MGD and maximum flows increased from 2.75 MGD to 5.0 MGD.
The Dunn Monthly WWTP Effluent Flows Chart points out that Hurricane Florence
had a negative affect and may have caused extensive damage to the sewer
infrastructure.
Remedial Action Taken:
o A $150,000 Wastewater Asset Inventory and Assessment grant was awarded in
March 2019 to assist with the funding needed to plan current and future
collection system and WWTP Capital Improvement Projects.;
o As a result of damage we feel was sustained to the collection system during
Hurricane Florence, the City applied and received $142,500 in October 2019, to
assist with conducting a sanitary sewer evaluation including smoke testing,
flow monitoring, and CCTV inspection. CCTV inspection work began the 4"`
quarter of 2019.
o The City of Dunn has an ongoing collection system cleaning and TV inspection
program. I&I issues that are repairable by City employees are addressed
immediately. Since January 1, 2019, the City has cleaned 53,125 LF and video
inspected 9,000 LF of gravity sewer mains.
o The City recently received a State Reserve Loan in the amount of $2,750,000 to
upgrade the deteriorated aeration piping and blowers at the WWTP. Due to the
deteriorated air piping, the WWTP limits the amount of flow through the plant
in an effort to minimize damaging the aearation piping any further. Therefore,
once the 3MG equalization tank reaches capacity, the collection system will
surcharge at manhole# BRE8 on the Black River Outfall line. Notice to proceed
was issued to the Contractor on 11-11-19. Construction is expected to begin the
190 quarter of 2020.
o The City's Engineer, Davis Martin and Powell, is currently preparing a
Prelimianry Enigineering Report and Environmental Review in order to pursue
Rural Development Grant/Loan funding for collection system rehab projects.
Once the Collection System Rehab Project phases have been finalized, it will be
presented to Council for their consideration.

As demonstrated, Operation and Maintenance personnel were responsive and took
immediate action to respond to the overflow and we believe this letter shows the
investment and commitment the City is making to resolve failing infrastructure, and
we hope that the Division recognizes these efforts. Therefore, we respectfully request
that the Division consider these efforts when deciding on further enforcement.
Steven Neuschafer
City Manager
DUNN
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