HomeMy WebLinkAboutNC0085812_Inspection Response_20190503Department of Public Works
WaterlWastewater Division
4600 Goldmine Road
Monroe, NC 28110
T704-289-1434
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May 3, 2019
Mr. W. Corey Basinger
Regional Supervisor
NCDEQ
610 East Center Ave, Suite 301
Mooresville NC 28115
Subject: Compliance Inspection Report
Grassy Branch WRF NPDES #NC0085812
Violation Response
Dear Mr. CBasinger,
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This is in response to your Grassy Branch WRF Compliance Inspection report letter dated April
15, 2019.
As we presented during our meeting with you on May 3rd, 2019, Union County Public Works'
(UCPW) field staff has been working diligently to find and repair sources of I&I in the basin.
Efforts include:
® CCTV survey of the entire basin.
® Smoke testing.
0 Plug testing during rain events.
® 42 Manholes repaired by Chemical grout injection.
a 48 inflow collectors installed
0 2 leaking laterals repaired
® Multiple clean -outs repaired
Since 2016, UCPW has commissioned Frazier Engineering to perform 3 flow monitoring
studies. Each of these has been used by field staff to focus investigation and repair efforts.
Another flow study is underway now.
In July 2018 UCPW contracted with Hazen & Sawyer to perform a WRF Process Survey to
determine any improvements that could be made in plant performance. Hazen evaluated all flow
data from 2014-2018. UCPW CIP engineers are looking at the Survey data to plan possible flow
equalization projects in the near future.
UCPW is committed to resolving the I&I issues in the Grassy Branch basin and operating the
WRF in a safe and ethical manner. If you have any questions or concerns please feel free to
contact me at 704-296-4215.
Sincerely,
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Andrew Neff, PE
Water & Wastewater Division Director
CC: Aubrey Lofton, Interim Public Works Administrator
Josh Brooks, Assistant Water & Wastewater Division Director
Bart Farmer, WRF Superintendent
Greg Morgan, Field Services Superintendent