ILLINOIS POLLUTION CONTROL BOARD

February 6,

1975

)

In the Matter of:

)

)

AIR QUALITY MAINTENANCE

)

R74—6

AREA DESIGNATIONS

)

)

)

ORDER OF THE BOARD

(by Mr. Dumelle):

Three hearings have been held in the proceeding R74-6

on

September 16,

1974

in Chicago,

on October

8,

1974

in Peoria,

and on October 15,

1974

in Edwardsville.

This proceeding would

designate

the areas

for which air quality maintenance plans must

be prepared by June

30,

1975.

The areas

to be designated have

as

their data base

1973

air quality data and 1973 emission inventory data

(R.

24).

The

methods used have been criticized by some witnesses

as being

too “rough” or too approximate.

1974 air quality data should now be available

(and perhaps

also 1974 air emission inventory data).

Since

it appears

that

a

Federal Regulation to be issued this month will postpone the June

30,

1975 mandatory date, we think

it best for the Environmental

Protection Agency to update its computations using 1974 data and,

if possible, more sophisticated modeling.

Two years of data are

better than one,

In addition the high oxidant levels experienced

in 1974 can be taken into account.

This proceeding will be deferred until May 15, 1975.

The

Agency will update its computations using 1974 data and make them

available

to the public by suitable means and submit them to the

Board prior to this date,

The Board will then schedule a final

hearing dealing with the updated material.

If additional

time

is

needed by the Agency

it can be requested from the Board,

IT

IS SO ORDERED.

I, Christan L. Moffett,

Clerk of the Illinois Pollution

Control Board, hereby certify the above Order was adopted on the

~day

of February, 1975 by a voteof

ristan L.

Mo

e

Cler

Illinois Pollutio

Contrbl Board