NC0030210_correspondence_19900502

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State of North Carolina
Department of Environment,Health and Natural Resources
Division of Environmental Management
512 North Salisbury Street•Raleigh,North Carolina 27611
James G. Martin,Governor George T.Everett,Ph.D.
William W. Cobey,Jr., Secretary Director
May 2, 1990
Joe C. Stowe, Jr.,Director
Charlotte-Mecklenburg Utility Department
5100 Brookshire Boulevard
Charlotte, NC 28216
Subject: Mallard Creek WWTP
NPDES No. NCO030210
Mecklenburg County
Dear Mr. Stowe:
In accordance with your recent conversation with Dennis R. Ramsey of my staff, please
find below further clarification on the Division's position on your concerns with the subject draft
NPDES permit. This letter is a follow up of my letter to you dated April 5, 1990. Also as per
your request, please find attached a copy of the modified draft permit that includes the factors on
which we have been able to reach agreement as well as all boiler plate conditions.
CMUD has expressed concern that the permit as drafted contains a fecal coliform effluent
limitation of 200/100 ml for both the period before plant expansion as well as following the
expansion. It is my understanding that you are concerned that the facility may not be able to
maintain compliance with this limitation as the flow into the plant nears 3.0 MGD prior to plant
expansion. Our review of your self monitoring data does not seem to substantiate this concern.
During the month of February 1990, the monthly flow into the plant averaged 2.75 MGD (91% of
plant hydraulic capacity) and the monthly average fecal coliform count was only 19/100 ml. Also
other months showed similar results. Therefore unless you are able to provide us with additional
information that helps substantiate your request, we must maintain our position that a compliance
schedule for this parameter is inappropriate for the permit.
The other issue was a request for the Division to clarify its position on when the more
stringent effluent limitations for BOD and ammonia would become effective. The attached draft
permit has been modified to hopefully remove any confusion as to when the new more restrictive
limitation would become effective. Specifically they would become effective the first month that
the average monthly flow into the Mallard Creek Wastewater Treatment Plant exceeds 3.0 MGD.
Pollution Prevention Pays
P.O.Box 27687,Raleigh,North Carolina 27611-7687 Telephone [phone]
An Equal Opportunity Affirmative Action Employer

Joe C. Stowe
May 2, 1990
Page Two
I hope that this letter will help you to finalize your position on this permit so that we will be
able to have it issued as quickly as possible. If there is a need for any additional information or
clarification, please do not hesitate to contact either Dennis R. Ramsey or myself at telephone
919n33-5083.
Sincerely,
Steve W. Tedder, Chief
Water Quality Section
Attachment
cc: Dennis Ramsey
Trevor Clements
Rex Gleason
Central Files