ILLINOIS

POLLUTION

CONTROL

BOARD

May

3,

1984

IN

TRE MATTER

OF:

)

)

AMENDMENTS TO

35

ILL

ADM. CODE 604.203

)

R84-12

AND 605.104 OF SUBTITLE F:

PUBLIC

)

WATER SUPPLIES

(Trihalomethanes)

)

Inquiry Hearing~s.

ORDER OF THE

BOARD

(by J.

D. Dumelle):

On October

5,

1982 the Board adopted amendments to Chapter

6:

Public Water Supply

(now 35 Ill.

Adm. Code Subtitle F)

in

R81—11

(49 PCB

101).

That action established a maximum allowable

concentration of 0.10 mg/l for Total Trihalomethanes

(TTHM)

in

finished drinking water

(35

Ill. Adm. Code 604.203)

as well as a

sampling program

(35 Ill.

Adm. Code 605.104).

Those rules,

however,

applied only to water supplies serving over 10,000

individuals.

In the Second Notice Opinion issued on July 21,

1982

(47 PCB

453),

the Board stated that:

since these smaller supplies generally use ground water

sources and have shorter transport times, they are consider-

ably less likely to have TTHM levels exceeding the 0.10 mg/i

standard.

At the same time, universal applicability would

greatly increase the number of water sample analyses which

the Illinois Environmental Protection Agency would have to

perform.

After more data are gathered on existing TTHM

levels, the Board may consider an additional rulemaking to

protect public water supplies serving less than 10,000

people.

In the eighteen months that the program has been in place,

the Board presumes that more data have been gathered.

Given that

research by the National Cancer Institute and the National

Academy of Sciences shows that TTHMs may be carcinogenic and can

lead to liver or kidney disorders, birth defects and central

nervous system damage, the Board concludes that it is approprate

to consider whether the TTHM standard and the sampling

requirements should be expanded to be made applicable to water

supplies other than those serving more than 10,000 individuals.

The Board,

therefore, authorizes the scheduling of inquiry

hearings to consider expanding the applicability of

35 Ill.

Mm,

Code

604.203

and 605.104.

The Board solicits comments and

58-67

---

2

proposals concerning these rules,

and, without in any manner

restricting the scope of the comments, proposals or hearings,

in particular

desires

that

the

following issues be addressed:

1.

In terms

of health protection and/or economics:

a)

Is classifying on the basis

of population appro-

priate for this rule;

is there a more appropriate

means.

b)

Is classifying

at a 10,000 population cut—off

appropriate,

and

approximately what percentage

of the State’s population is covered at this

cut-off.

2.

Should supplie~exempted from the requirement to

chlorinate be required to comply with this rule?

3.

Should supplies that provide no treatment other than

chlorination be exempted or treated differently?

4.

To what extent can the number of

affected facilities

be enlarged without creating

an undue administrative

sampling burden?

IT IS SO

ORDERED.

I, Christan T~, Moffett, Clerk o1~ the Illinois Pollution

Control B~d hereby certify that the above Order was adopted

on

the

~

day

of

~

~

1984 by a

vote

of

~

Chris tan

TT

~of’fe~,Clerk~

Illinois Pollution Control Boarl

58-68