ILLINOIS

POLLUTION CONTROL BOARD

September

30, 1971

In

the’

rratter of

#R71—12

OHIO-WABASH THERMAL STANDARDS

u~inion

of

the Board

(by Mr.

Currie):

We have today adopted new temperature regulations for the

ohio and Wabash Rivers,

after public hearings and upon

the record.

This coinion gives

the reasons for our

action.

Excessive heat, everyone concedes,

can pollute.

As

is

extensively discussed in the Board’s opinion in #R 70—2, Thermal

Standards,

Lake Michigan

(June

9,

1971), water that

is too hot

can seriously disrupt stream or lake ecology

in

a number of

ways,

such

as by killing fish,

by interfering with their re-

oroductive patterns,

and by unfavorably affecting

the algae

a;d

other

plant

populations.

How much heat

is

too much is

of course

a critical and much

dis~utedquestion, bound up not only with the temperature

of

a

heated

discharge but also with

the area of the stream affected,

which

in turn depends upon the relative volumes of

the effluent

and of

the receiving body.

And

in determining what portions of

a

stream,

if

any, may be raised above temperatures desirable for

th2

natural biota,

the Board must under

the statute consider

the

o~tcn

considerable

costs of providing alternatives

to the use of

stream water

for cooling purposes

in power generation and

in industr

gen?rally.

Environmental Protection Act, section

27.

Present regulations

(SWB-9 and SWB-l0)

provide that the

temper

ature

of the Ohio and Wabash Rivers shall not exceed 60°during

winter nor 90° at other times, and that there shall be no increase

of more than 5°above natural water temperature.

These figures

represent the dual policy that temperatures should be kept near

normal

at all seasons and that there

are certain extremes that rust

be

avoided

even

when

normal

variations

are

preserved.

We

have

been

asked

by

the

federal

government

(USEPA)

to

rev~

these

standards

slightly

by

specifying

monthly

rather than seas~. al

m~::~mum

temperatures.

Federal

approval

of the Ohio and Wabash

River

~~ndards

is

contingent

upon

our

making

this

change,

and federal

approval

is

essential

to

full

federal aid in the funding

of mun~i~I

sewage

treatment

facilities

on

these

streams,

The

suggested

moo Lhl~~

ma:~ima have

been

adopted

by

both

Indiana

and

Kentucky

to

govern

~

hertions

of the

Ohio

River

and

by

the

Ohio River Valley Sanitat~

---

Commission

(ORSANCO),

to which Illinois is a party,

to govern the

entire river.

They appear

to be related both to actual tetn~erature

records

(P.

9)

and to maximum r~err’issihletenp~raturcsconsistent

with the successful maintenance of the natural ~iota, ~s determined

by federal biologists

(P.

53—S5).

The

necessity for

thlv

maximum temperatures

in addition to the general c°-riselir~itatior~

was

well

explained by the statement of Pr.

flonalc’

Mount,

Pireetor

of the National Water Quality Laboratory:

Experimental evidenee

is

convincing that the teri~~orature

providing best gro’~th

of

fishes is hut a few~degrees cooler

than a lethal temperature.

For this reason, sn~~jej~~

permissible maximum temperatures must he adhered to.

Even though channel catfish are a bottom dweilinq animal,

the newly hatched fry stay at the surface for several days

before moving to the bottom.

Water that is too warn at

the surface during that period will completely destroy

the year class.

This provides ample reason to adhere to

the temperature limits prescribed and explains why operation

of cooling devices for even a few days warrants their cost

of construction.

,(l~. 49—50,

54).

in short, the principle of maximum tcmneratures, areaciv

recogni~ed

in the Illinois regulations,

is essentially an analea to the familiar

regulations prescribing special emission reductions durine air

pollution emergencies.

It does no ~nod to nreserve a fish

population for the bulk of the year and then to snuff them out

or to destroy a year’s crop of young.

We aeree that maxima

must be provided.

There was objection to the sunqested monthly maxi’~a

on

the

ground they might, as Dr.

*1r,nnt

i~rplied,reauire exnensive con-

struction of standby facilities or

result

in

plant

shutdowns

during emergencies

(P.

96).

And so they

mi&it,

tuit so

mi~ht;

the existing standards.

A comrarison between the

eviStit~~i

and

the

proposed maxima demonstrates the likelihood t~mtanyone with su~h

a problem under th~federal prop~s~l

would ha~e

a

si1a~-

oroh~

under the present law:

Proposed Jan.

Feb.

Mar.

Apr.

May

June

July

Ang.

~ept.

~et

“ov~

~

Ohio(°F.)50

50

60

70

80

P7

~9

On

~)7

~

r7

Proposed

Wabash(°F.)50

50

60

70

~‘fl

90

7~

7~

Present

60

60

60

90

50

~

9~

~

90

~i

(~

Given the fact that

SUrnmE~

temzrratures

in

th~c~~

ri;’ers

naturally

have

reache~~~3° en

0~it—~-

~

~)

,

+

soe~

ci~oar

that

the

present

regu~

I

~ris

already

jnr

ose

an

di seharoers

tb~

ö.uty

to

provide

assura

that

temperatnres

at

times

‘7fl1

nr-~:

he

raised

above

the

na~ ~ril.

Whether

this

must

he

achieved

2

—

5b4

---

once in three years or twice in one,

if such a comparison

could

here

be made,

seems not very material,

since the crux of the

objection is that

it is unreasonable

to require such assurance

at

all..

In short we find that the changes suggested by USEPA,

while aff.ordlng more precise protection to the environment, do not

have

a significantly different effect upon those discharging heated

effluent than have the existing regulations.

Much

is made of the

fact that

the maxima change abruptly at the

end

of each month

(R.

15,

88),

but

the present standard

is more abrupt yet,

since

it

changes by thirty degrees in

a single day.

Short

of an

unwieldy table with

365

different maxima, we think it would be

difficult to improve on the proposed table

in this regard.

Also

the subject of

cofltention at the hearing was

the

provision specifying that

the 5°—rise limit and monthly maxima

be m’~twithin

no more than 600’

from the point

of discharge

(R.

106,

108, 116—17).

One witness argued that

1000’ would be required to

avoid,

expensive

cooling

devices

in generating stations

of over

600

mw

and

that

the

larger zone would not be harmful to the water

as

a Whole. Another

urged

that

no

mixing

zone

at

all

be

provided,

apparently

intending either,

as

in

the

Indiana

regulation,

that

opportunity

be

given

for

‘Treasonable

admixture,”

or

that

stream

temperature

be

computed

on

the

assumption

of complete mixing.

Neither

of

these

modifications

would be acceptable.

Complete

mixing would allow virtually

all the river to be raised above the

standard,

so long as

at some point distant .in time and space it

could theoretically

be expected to return to normal.

And “reasonable

admixture” would be too imprecise

a standard either for enforcement

purposes

or for the guidance of those who must design and operate

facilities

for the control

of heated discharges.

It

is our

obligation

to specify c~arlywhat area,

if any,

is exempt from

the standards.

It would of course be possible to

do without mixing zones

and to require that

water

quality

standards

be

met

at every point

in the stream.

This

is obviously

a desirable goal.

It woicld

reouire, as we have proposed (#R 70—8) for a number of toxLc

contaminants,

that effluents discharged themselves meet the standards

for the receiving stream.

But such a requirement would have its

costs,

for it would sharply restrict the use of the streams for

purposes of cooling and

of waste

~

The

coneeot

of

,~ht

mixing

zone is

a compromise designed

to allow relatively snail pertions

of~

a stream to

be degraded below

desirable conditions

in order

to

reduce the

cost. of pollution control.

This compromise

is built into the existing regulations dWB—9

and SWB—lO, which provide that water quality standards must be met

everywhere except “inmediately adjacent to outfalls” and after

opportunity

for “admixture”

of stre~imand effluent.

No

figures

specifying the

size

of the exen~ptedarea appear

in the regulations

themselves, but

in

order

to provide guidelines for design and en-

forcement the Technical Secretary of the Sanitary Water Board,

which

~3’~’rtod

the

~

~

~

~.s

,

I .~:ei~o

ir

T ~‘roretatiori~f

7

—

565

---

the rules in Technical Release 20—22, which provides that

reasonable admixture

is deemed to occur within 600’

from the outfall.

In re Commonwealth Edison Co.

(Dresden),

#

70—21

(March

3,

1971),

this Board held that

it would adhere to the Technical Secretary’s

interpretation of the size

of the mixing

zone

in the comparable

regulations

SWB—8,

governing

the

Illinois

River.

Thus

the present

proposal to specify

a 600’

zone

is nothing more than a restatement

of

the

present

law

as

it

has

been

construed

by

this

Board.

We

are

aware

that

the

600’

zone

may

or

may

not

be

the

ultimate

best provision on this subject.

For one thing,

it was apparently

based

upon

a

misconception

as

to

the

distance

within

which

heat

from a rather large electric plant

could

be

dissipated

without

special cooling de~’ices (R.

27).

Whether that criterion, with or

without the misconception,

is appropriate is another question,

depending on the cost of

cooling methods

and

the effect of zones

cf that size upon the particular stream.

Moreover,

a complete

program

of

proteqtion

against

thermal

pollution must consider

not

only the

area

of

an

individual

mixing

zone

but

the

number

of

zones:

The ob~ervationsemphasize the need for better conditions

in the bulk of

the

receiving

water

than

exist

in

the

plume.

The f2sh are found to leave the plume because

it is unsuitable,

and

nbviously it follows that they must

find a cooler place

to ~o.

(R.

51).

Further, consideration must be given to forbidding zones that

block passage up or down a stream, and to special provisions for

avoiding interference with spawning grounds, the shore,

or the

bottom (R.

6—7,

56—57).

Some of these considerations have been

incorporated into

our

new Lake Michigan thermal standards,

#r~

7O-2~

and

some have been made part of the regulation adopted today.

We recognize therefore the desirability

of further reexamination

of the standards today adopted.

Indeed we have already begun

hearings on a comprehensive proposal

(#H71-14

)

to overhaul and

restate the entire package of water pollution regulations, and

additional provisions regarding thermal pollution are included.

These hearings will afford an ample opportunity to revisit the

troublesome question of the mixing zone as well

as the monthly

maximum figures..

In the meantime we have insufficient basis for

altering the present law as to the 600’ mixing zone, and we there-

fore continue it in effect by adopting the proposed Ohio and

Wabash standard.

We are asked to provide that the standard apply

to

a 24—hour

average temperature, rather than to a single sample

(R.

91—92).

Once again we are unwiling

at this point to change the present

law without more proof, especially

since

to re~ju~re

evidence of

such an average temperature might impose quite an impracticable

burden on the enforcement process.

2—566

---

On the other hand we think it wise

to permit

monthly

maximum

temperatures

to

be

exceeded

by not more than

30,

so

long

as

the

5°-rise

limit

is

adhered

to,

for time periods too brief to have biological significance,

and

we have added

a provision to that effect.

We have

also,

for

reasons given in the Mississippi case,

added

a provision specifying

that

the monthly maxima are to be met in the main part of the

river, believing this will afford adequate protection against

excessive temperatures

in the naturally warmer shallow backwaters.

The Illinois Evvironmental Protection Agency, while generally

acceding

to the proposed standard,

asks that we make

it applicable

to new sources only

CR.

11) and that we couple it with an ORSANCO

formula for determining permissible discharges

(R.

6,

21-22).

We

decline to do so.

The present standard applies to existing sources;

we

see

no

reason

why

the

new

one,

which

as

we

have

said

is

not

substantially

different,

should not do so too.

And the ORSANCO

formula has not been shown to assure that the water quality

standards will be met at the

edge of the mixing zone.

The formula

may

be

an acceptable means

of defining

a mixing zone otherw~se

unspecified, but

it has not been shown to fit with

our standard,

and whether

it adequately provides

for emergency situations

is

unclear.

This cuestion too can be further explored in future.

One

final point must be considered.

One witness questioned

our authority

to regulate the Ohio River on the ground that

it

lies entirely

in Kentucky,

the state

line falling at the low-water

mark on the Illinois

side

(P.

116—17)

.

We disagree.

Illinois

has long had water quality standards for the Ohio,

and federal

law

requires

that we have

if we are to receive

full federal funding

for sewage treatment plants, concededly our responsibility,

that

discharge into

that

river.

We have

a duty to Kentucky and other

river states

to limit pollution of the Ohio from Illinois sources,

and

the statute expresses

the state’s

strong policy

of protecting

the quality of border waters

for the benefit of Illinois citizens

who use them and for

the protection of riparian interests

of Illinois

landowners.

Section

13

of the Act authorizes

the adoption of water

quality standards

for all “waters,” and “waters”

are specifically

defined

to include not only those ‘~ihich “are wholly or partially

within”

or “flow through” Illinois, but

also those which “border

upon this State”

(section

3(o)).

Our statutory power

is clear,

and

the strong and obvious interests of Illinois

in the condition

of

this bordering stream are ample

to sustain the constitutionality

of

our

jurisdiction.

In sum we think it aenrorriate,

pending further review of the

entire thermal

ccllution issue

in pending hearings,

to assure the

‘rovision

of federal funds

for sewage treatment plant construction

b!

;mdooting the monthly maximum temperatures proposed by USEPA

for

the Ohio and Wabash

Rivers,

and in other respects

to preserve

2

.

56/

---

existing

law.

The

amendment,

as

we

have

said,

should

afford

more precise protection to the biota without imposing any

significant

new

burden

on

those

utilizing

the

streams

for

cooling

purposes.

As

in other cases,

we also require that the effects

of new large sources be studied and that correction be made

if

significant harm is shown.

The present standards are based on

current

knowledge,

which

is

incomplete;

we

must

review

them

in

the

light

of

future

learning.

2

---

ORDER

I.

Rule

l.05c

of

Rules

and

Regulations

SWB—9

and

SWB—l0

are hereby amended to read as follows:

All sources of heated effluents shall meet the following

restrictions outside of

a mixing

zone which shall extend

no

farther

in

any

direction

from

an

effluent

discharge

than

600

feet.

The

mixing

zone

shall

include

no

more

than one-fourth of the cross sectional area of the river

nor

shall

it,

at any time,

extend

to more than one—half

of

the

surface of any river sector.

A.

There shall be no abnormal temperature changes that

may affect aquatic life unless caused by natural conditions.

B.

The normal daily and seasonal temperature fluctuations

that existed before the addition of heat due to other than

natural causes shall be maintained.

C.

The maximum temperature rise at any

time

or place above

natural temperatures

shall not exceed 5°F.

D.

In addition,

the water temperature at representative

locations

in the main river shall not exceed the maximum

limits

in the following table during more than one percent

of the hours

in the 12-month period ending with any month.

Moreover,

at no time shall the water temperature at such

locations exceed

the maximum limits in the following table

by more than 3°F.

JAN.

FEB.

MAR.

APR. MAY JUNE JULY AUG.

SEPT.

OCT.

NOV.

DEC.

Ohio

River(°F)

50~ 50°60°

70° 80°87° 89° 89° 87°

78° 70° 57°

Wabash River

& Other

In—

terstate

50° 50°60°

70°80°90° 90° 90° 90°

78° 70° 57°

Tributaries

(°F)

Main river temperatures

are temperatures

of those

portions

of the river essentially similar to and

following the same thermal regime as the temperatures

of the main flow of the river.

---

II.

A.

The

owner

of

operator

of

a

source

of

heated

effluent

which

discharges

0.5

billion British thermal units per

hour

or

more

shall

demonstrate

in

a

hearing

before

this

Board

not

less

than

5

nor

more

than

6

years

after

the

effective date of these regulations

or,

in the case of

new

sources,

after

the

commencement

of

operation,

that

discharges

from

that

source

have

not

caused

and

cannot

be

reasonably

expected

to

cause significant ecological

damage

to

the

River.

If

such

proof

is

not

made

to

the

satisfaction of

the Board appropriate corrective measures

shall

be

ordered

to

be

taken within a reasonable time as

determined

by

the

Board.

B.

Permits for heated effluent discharges, whether issued

by

the

Board

or

the

Environmental

Protection

Agency

shall

be subject to revision

in the event that reasonable

future development creates

a need for reallocation of

the assimilative capacity of the river as defined

in the

regulation above.

C.

The owner or operator of

a source of heated effluent

shall maintain such records and conduct such studies of

the effluents from such source and

of their effects

as

may be required by the Environmental Protection Agency

or

in any permit granted under the Environmental Protection

Act.

D,

Appropriate

corrective

measures

will

be

required

if,

upon

complaint

filed in accordance with Board

rule’s,

it

is found at any time that any heated effluent causes

significant ecological damage to the River.

III.

Paragraph

4 of Rule 1.08 of SWB-9

and SWB-lO

is hereby

repealed.

2

57C