NC0085812_NOV and Intent to Assess_20190401

Department of Public Works
Water/Wastewater Division
4600 Goldmine Road
Monroe, NC 28110
T. 704-289-1434
F. 704-289-7395
www.unioncountyne.gov
April 1, 2019
Corey Basinger,
Regional Supervisor
NCDEQ (use same address line as the other letters)
610 East Center Avenue, Suite 301
Mooresville, NC 28115
Dear Mr. Basinger,
This letter is in response to NOV-2019-LV-0184, exceedances experienced at our Grassy
Branch WRF.
The high flow at Grassy Branch WRF was due to I&I introduction during heavy rains and flash
flooding. This has pushed the water table to record high levels. We continue to address I&I
issues in this basin as outline below:
Y 2016-2017(Phase 1) Flow monitor study for Grassy Branch Basin was conducted by
Frazier Engineering.
® Then, smaller key areas were identified and monitors were placed for further studies
evaluation.
• In February 2018, the Smithfield Subdivision tie in to the main trunk line flowing to the
Grassy Branch Basin plant was evaluated.
C Since May 2018 staff has,
o Repaired 12 manholes with chemical grout
o Inspected via CCTV over 15000 feet of sewer main and evaluated condition
o Plug tested outfall in ever rain event
o Smoke Tested over 21500 feet of sewer pipe
o Repaired 23 Lateral Connection
o Installed over 40 Inflow collectors
o Replaced 8 manhole lids
o Excavated and repaired 2 manholes
0 CCTV work and flow testing continues in this basin
In our previous responses dated 3/12/19 and 1/17/19, we detailed our continuing efforts in
reducing the I&I that is entering the Grassy Branch collection system. We have also engaged
Frazier Engineer in another sequence of flow monitoring to gain a better understanding of where
the I&I is occurring.

We intend to continue our efforts finding and addressing I&I in the Grassy Branch basin.
Sincerely,
't
Andrew Neff. PE4
Water & Wastewater Division Director
Cc: Aubrey Lofton, Interim Public Works Administrator
Josh Brooks, Asst. Div. Director, Water & Wastewater
Bart Farmer, WRF Superintendent
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