icipal

Utilities

333 Lincoln Highway

P.O. Box 456

Rochelle, IL 61 068-0456

Office: (815) 562-41 55

Fax: (815) 562-5861

RECEIVED

CLER~cS0

MAR 6

2002

Illinois Pollution Control Board

Attention: Dorothy Gunn, Clerk

STATE OF 1WNOIS

James R. Thompson Center

Pollution Control

Board

100 West Randolph Street, Suite 11-500

,47

Chicago, Illinois 60601

Re: Docket R02-11

Dear Sirs:

The City of Rochelle supports Mr. Al Keller’s testimony to recognize Carbonaceous

Biochemical Oxygen Demand (CBOD) for effluent limits of NPDES permits issued in

the State ofIllinois.

The article, “Chemical method for nitrification control”, Journal of Water Pollution

Control, Volume

45,

Number 4, April 1973, states that nitrification control should be

adopted as a routine practice in the measurement ofthe BOO for all wastewaters. The

work for this article was supported by an EPA grant. Depending upon the source

material, the five-day time period for the BOD test was chosen either because it was

developed in England, and it takes at most five days to reach the sea, or because

nitrification does not occur until five days after the start of the BOO test. POTW’s that

are required to nitrify do have adequate numbers for nitrifying organisms resulting in the

measurement of the nitrogenous and carbonaceous demand in the five-day BOD test for

effluent waters.

The City of Rochelle has had an effluent ammonia limit since 1983, and was granted a

permit modification in March 1987 that changed the BOD discharge limit of 10 mg/L to a

CBOD limit of lomg/L, monthly average. The revision was granted after submittal of

one-year’s data showing comparisonof BOD and CBOD values ofthe discharge.

Sincerely,

Kathy Cooper

Superintendent Water/Water Reclamation

cc: KenAlberts, Director ofUtilities

March 4, 2002

Electric • Water Reclamation • Water • Communication Services