ILLINOIS POLLUTION CONTROL BOARD

June 23,

1992

COMMONWEALTH EDISON COMPANY,

(BYRON)

)

Petitioner,

v.

)

PCB 91—199

)

(Permit Appeal)

ILLINOIS ENVIRONMENTAL

PROTECTION AGENCY,

Respondent.

ORDER OF THE BOARD

(by G.T. Girard):

On June

16,

1992,

the parties

filed

a

status

report.

The

parties report that the permit condition which

is the subject of

these

consolidated

appeals

concerns

compliance

with

effluent

limitations

for bromine—based biocides

in Commonwealth Edison’s

condenser cooling water.

At the time the permit was issued, USEPA

had before it a chemical industry study on the toxicity of bromine

biocides.

USEPA has recently concluded its review of the study,

which indicates with more precision the levels at which bromine has

toxic effects.

Based on the results of the study,

the Agency and

Commonwealth

Edison

are

currently

engaged

in

settlement

discussions,

and have reached agreement in principle.

The points

which

remain to be finalized included evaluation

of alternative

cleaning mechanisms

for

Commonwealth

Edison’s condensers

and

a

schedule for compliance with the bromine effluent limitation to be

placed in the company’s modified NPDES permits.

Once the

specific terms

of Commonwealth

Edison’s modified

permits are set, the Agency will reinitiate the NPDES draft permit

public comment and review process required by 40 CFR Part 124.

At

the end of that process, the Agency expects to issue final modified

NPDES “settlement” permits to Commonwealth Edison.

The parties are directed to file an updated status report on

or before September 15,

1992.

This updated report shall contain an

estimated date for the conclusion of this matter.

IT IS SO ORDERED.

134—327

---

2

I, Dorothy M.

Gunn,

Clerk of the Illinois Pollution Control

Board, ~hereby certif-y) that the above order was adopted on the

•-~/~day of

_______________,

1992, by a vote of ~

Dorothy M.

Illinois Poll

Clerk

Control Board

134—328