CLERK S OFF~r~

Re: Proposed amendments to dissolved oxygen standard (R04-25)

NOV

032004

Dorothy Gunn, Clerk

STATE

OF ILLJNo~

illinois Pollution Control Board

POllution

Contro~

Bo~r~

James R. Thompson Center

100 W. Randolph St.

Suite 11-500

Chicago, IL 60601

Dear Ms. Guna,

In April 2004, the illinois Association of WastewaterAgencies (IAWA) submitted aproposal to the illinois Pollution

Control Board proposing to lower the dissolved oxygen criteria from 5.0 mg/I to

3.5

mg/i during the months of July

through February. 1 am writing you to ask that you reject IAWA’s request The proposed reduction in dissolved

oxygen criteria will not improve the condition of Illinois streams such as the Fox River, rather it will have the

opposite effect by further degradingwater quality and harming aquatic life. The current illinois standard for

dissolved oxygen follows U.S. Environmental Protection Agency guidelines and past scientific studies do not

support a lower standard. Therefore, the Illinois Pollution Control Board should rejectthe proposal to lower

dissolved oxygen standards.

Tn 2002, the Fox River was categorized as impaired by the lllinoi.s Environmental Protection Agency. One of the

reasons forthe river’s impairment is low dissolved oxygen. The effects of low dissolved oxygen in rivers such as

Fox are well documented. At extremely low oxygen levels, fish kills result. Low dissolved oxygen levels in the Fox

River will also negatively impact fish species that spawn in late summer, and sportfish such as smalimouth bass are

sensitive to low dissolved oxygen levels. Freshwatermussels and other aquatic macroinvertebrates are also

negatively affected by low dissolved oxygen. The aquatic fauna in the Fox River is already threatened by

deteriorating water quality with several species becoming extirpated from the watershed in recent decades. Lower

dissolved oxygen will only exacerbate the problems the Fox River faces.

Robert Schanzel made the following comments on behalf of the Illinois Chapterof the American Fisheries Society

regarding the proposal: “TheIllinois Chapterof the American Fisheries Society does not support relaxing Illinois’

existing dissolved oxygen standards because insufficient evidence is available that such actionwill not have serious

and irrevocable consequences forthe state’s aquatic biota

-

that is, the science does not support the proposed

changes.” Schanzel also states “To lower quality standards now, would not serve the best interests either of Illinois’

citizens or its aquatic resources.”

The condition ofthe Fox River is impacted by multiple stressors. As these stressorsbecome intensified the

ecosystem deteriorates. The degradation of the Fox River has and will continue to affect the well being ofits

residents. Tn February 2004, over 150,000 residents in Aurora were recommended to boil their water. A report

prepared by Weston Solutions indicated that the majority of the blame for the boil order could be placed on the

deterioration of water quality in the Fox River. The proposed rule change by IAWA will not improve the condition

of the Fox River, but it has the potential to accelerate its declining condition. Thus, it should be rejected by the

illinois Pollution Control Board.

Thank you very much for your time and consideration.

Sincerely,

NG-DeVRJES

ASSOCIATES

9620 ZIMMER DRIVE

ALGONQUIN, ILLINOIS 60102