ILLINOIS POLLUTION CONTROL

BOARD

September 11,

1986

IN THE MATTER OF:

)

)

SITE—SPECIFIC RULEMAKING

)

R85—7

FOR

CENTRAL

ILLINOIS LIGHT

)

COMPANY.

CONCURRING OPINION (by

3. D. Dumelle):

This proceeding revolves around

the non—compliance of the

CILCO ash pond effluent as compared to other power plant ash

ponds.

There does not appear to be any measurable environmental

effect

(R.

64).

In fact, the existing effluent is far cleaner

than the turbid Illinois River at the discharge point

CR. 65).

On a total suspended solids basis, the River averages 80 mg/l

compared to the ash pond’s

17 mg/l

(R.

38 and

Ex.

3).

I would suggest that CILCO collect data on the amount of

colloidal substances

in the incoming and outgoing river water

(R.

76—77).

CILCO should also determine if algicide application

would be practicable.

Under the “background” portion of the

Board’s rules

a credit would be allowed

for the suspended solids

proven

to be from the river.

Perhaps this credit alone would

achieve compliance.

The water quality of the Illinois River

at the Edwards

Station

is being “enhanced” by the ash pond effluent since that

effluent is only 21

as turbid as the River.

Is

it worth

$14,000,000 of Central Illinois ratepayers funds to further

enhance the River’s water quality?

How can this ash pond be

distinguished from all other ash ponds in Illinois

if this

exception were to be granted?

These are the key questions which

need to be answered.

Finally,

a topic not discussed by anyone

in this proceeding

is the possible use of tube settlers

to aid

in the removal of the

suspended solids.

Would they improve the ash pond’s settling

efficiency and,

if so,

at what cost?

If the information needs mentioned above are filled then

I

would be amenable to re—evaluating this proposal.

Chairman

72-381

---

—2—

I, Dorothy

M.

Gunn, Clerk of the Illinois Pollution Control

Board,

hereby certify that the above Concurring Opinion was filed

on the

_________________

day of

_______________

1986.

Clerk

Dorothy M

Illinois Pollution Control Board