ILLiNOIS

POLLUTION

CONTROL

BOARD

August 22,

1984

MOEIL

CHEMICAL

COMPANY,

PCB

83—166

~:NVIRQNMENTAL PROTECT:roN

AGENCY,

Respondent.

OPINION AND ORDER OF THE BOARD

(by Bill S~Forcade):

On November 15,

1983,

Mobil Chemical Company

(“Mobil”)

filed

a Petition for Variance from

various water pollution regulations

applicable to its De Pue facility

until November

15, 1988~

In

response

to

Board Orders, Mobil

filed an amended petition on

February

3,

1984 and a second

amended petition on March 26, l984~

The Illinois Environmental

Protection Agency

(~Agency”)

filed a

recommendation on May 21, 1984

that variance be granted

but

for a

shorter term and with

more stringent limitations

than

requested

by Mobil.

On June

7,

1984,

the Agency and Mobil met and, after

discussion, agreed on appropriate

interim

limitations should the

variance be granted.

No

hearing was held, no comments were

received

Mobil requests

a

f:ive~year

variance for water quality

standards for

35

ilL Mm. Code

302~2l2(ammonia nitrogen and

unionized ammonia)

and :302~2o8

(quoride~total dissolved solids,

and sulfate)

for ~ts Outfall

002..

Mobil was previously granted

a one—year variance for certain

water quality standards applic-

able to Outfall 002 on November

12,

1982 in Mobil

Chemical

Co~,

v~Illinois Environmental

Protection Agency, PCB 82—18,

49

T~W2’75,

Mob

ii

provided a

copy of the Opinion and Order in that

case, as attachment ~‘A~to

the

Petition, to provide general

background information on the

facility, outfall and receiving

waters;

that. information will

be

repeated

here:

MohiLs phosphate

fertilizer manufacturing operation

employs 117 employees to

produce

250,00 tons of fertilizer

per year from the raw

materials phosphate rock,

sulfur, and

ammonia..

The facility

consists of a sulfuric acid manufactur-

ing plant,

a phosphoric

acid manufacturing plant,

and a

diammonium phosphate (DAP)

plant.

To the extent Mobil

requests a variance for Outfall 001,

the issue

is discussed infra

at

59-397

---

Outfall

001 discharges non-contact

cooling

water and boiler feedwater treatment

effluent.

Mobil

currently draws

15

million gallons per

day

(mgd)

of water from the Illinois

River for

use in its operation, but has the

capacity

to draw

20..3

mgd..

98

of this water,

14.6 mgd,

is used “as is”

for non—contact

cooling of

sufuric and phosphoric acids.

An additional

94,500 gallons are used “as is~for

dilution

water in the sulfuric acid plant.

~iat has been called Outfall

002 consists of

groundwater seepage from gypsum storage

area

and clearwater pond used in Mobiles

phosphoric

acid manufacturing process.

The

gypsum/clearwater

pond treatment system operates on

closed—loop

basis..

In this recycling system, water

serves

as the transport medium for gypsum

produced during

acid manufacture and filtered out of the

acid.

Gypsum is slurried with pond water and

pumped to

the gypsum disposal area.

The gypsum

is settled

in the gypsum pond,

and most of the

clear water

is recycled to the acid plant.

However, seepage

from the gypsum pond flows

into an unnamed

ditch

running along the perimeter

of the gypsum/clear-

water pond system..

This

ditch is tributary to Negro

Creek, which is tributary to

the Illinois River.

Seepage to the unnamed

ditch ranges from 10, 000

to 28,000

gpd..

The ditch

fails to comply with

the state~swater quality

standards

for fluoride,

ammonia nitrogen, TDS and pH,

and with the

federal phosphorus standard,

Stream samples

taken 1,200 feet downstream

of the process

wastewater treatment system in

the period

November,

1981 through January,

1982 showed

levels for these parameters in the

following

ranges:

Fluoride

5.64

—

36.0 mg/I

Phosphorus 131.

—

402,mg/l

Ammonia

63.4

—

230.0 mg/i

pH

6.54

—

7.27

TDS

1,224.0

—

4,556.0 mg/i

Mobil has had a long history of

problems with the

pond system, which received its first

operating

permit

in

1972..

Mobil states that

when

the

ponds were first

constructed, state-of—the-art

industry design recom-

mendations were for installation

of separate

leak

and

seepage containment systems

along the ponds’ base.

Mobil felt that an improved

design

eliminated the need

for such containment systems,

particularly since a

natural clay layer between

5 and 25 feet thick under—

lays the ponds.

The same

design system was employed

59-298

---

a a

19

-

a’~ansionof the gypsum pond, at which

aua~a 12

inc.i eLy

liner was put inside the expanded

ei~

.ie~

d~

L

‘mei in

he pond walls.

In 1977

the

~

~c.s~ed u~paeental permit allowing

for con—

s~uetLor

of

a

co’lection pond (swale)

to contain

~a

~~age iroo

‘-

a

gy~

m

pond prior to its

being

pinp~dbaelr

a c~earwaterpond,

An

experimental

pe~n~t~a-

~JaU~

to allow

construction and

ira~i~laLi

~.

of t~opilot test collection

trenches,

~C

4

asi~

t

~.

he

125 feet along, and

appurtenant

pe

~uo,

aid ~o al ow re—routing of

the unnamed

.

-

-h

~7

a-

‘..j~

—r

permitted to test

the feasi—

—~liLj

of

iriLr.-~

ting

seepage

from

the

gypsum pond

oefore

its

antoy

into

the

ditch.

The

Agency reports

that

only

the

43

root

trench

was

built,

and that

its use

die

ontiaed

by

Mobil

in

1981

since

the

company

fe)t

it

had

-J2n~ffcant

effect..

Finally,

in October

t98

Je

Actercy

i

~‘ucd

Mobil

a

permit

to operate a

coLtection

sum

a.

d

jump

back

system.

This involved

the

tho’e

dee

-

bed

re

routing

of

a portion of

the

ditch

aid

use

another

portion

to

collect the seepage.

The

..ump

is

u~a-J Ic

dewater

the

general area upstream

of

the

Iocatitn

~eru

the

existing

ditch joins the

by-

pass.

WatE.r

i~

~ riped

back

to the swale,

Nobil

a.oite~

-haF

it

expended $90,000 in

1978

to

instctJl

~nc

ewale

arid pump system along

the base

of

the

affectth

pcod

A~this

took care of

only 90

of

.na

scei-’

r.

cgan

further investigation

as

t

tri.

p

oL~

scarce

Some

4

years and $95,000

later,

Mobi’

~t

-ccc

that

it

believes that

an opening

haa

develop~

~

ong

the

base

of the pond~s

earthen

uiw

u1lu~iing

bud~

cuantities

of water to

seep

out and

t1u’~’bel

-~

Jroc

-I

-iveJ

along

the top of the area’s

~nderlying

c

-y

layer,

to

emerge in the unnamed ditch.

as

toa~d gtar

~

4

Mobil

a

one—year

variance

in

that

case

subject-

Fo

speciLc

li-aitations

and

a

requirement that Mobil

desigo.

rid

coi sti

w

a

o

L.onal

control

mechanisms.

Mobil

complea-~d

11

raotir~d

~c

i~ties

in March

of

1983,

ahead

of

the

Lath’s

r

~io1

schedule

(Pet,,

¶6).

Despite

com-

pletion

of

the

rcct~Lcd

iriprovements

Mobil

still

did

not

comp~

~ith

t~c

lL~

limits.

In

early

October,

1983,

Mobil

~n

gmented

th

~v

Ler~ with

the

addition

of

a

1,500

foot

coi1ection

sy-

a:

extension,

The

original

system

and

exteae

a

was

cour

h

Li

at

a

cost of

$135,000

(Am..

Pet,,

i_a

4)

Uttough

~ccutxations

of

fluoride,

ammonia

nitrogen

and

to-Li

dissoivc

.~o.

de

(“TDS”)

have

decreased

significantly,

Mobil

is

stil

I

trial

~e

to

achieve

full

compliance

(Am..

Pet,,

¶B6)..

i~-aeri1o~

~

indicate

a

trend

towards

decrease

---

—8—

of total pollutant discharge on an average

basis even though

concentrations

fluctuate

significantly

based on

weather-

related

factors

(Am,

Pet,, ¶B7(a)),

Mobil

is not aware of any way to

achieve immediate com-

pliance with applicable standards or any

effective way to

eliminate

seepage.

Neither

plant shutdown

nor production

curtailment

would

affect

the

seepage

(Am. Pet,,

¶~).

The

Agency

agrees

that

compliance

would be

technically difficult

here

and

that

the

present

approach may be the

best available

even

though

it

has

not

provided

a complete

cure

(Rec,,~ll),

Mobil

retained

an

environmental consultant to evaluate

the

impact

of

the

seepage

on

the receiving waters.

The

consultant

concluded that natural factors limiting the

development of

the stream are as significiant as,

if not greater

than,

the

seepage influence

(Am,

Pet.., ¶88),

Specific natural

factors

limiting

development

included:

I..

The

size

distribution

of channel bottom material,

2..

Availability

of

sunlight or shading,

3,

Depth

is

shallow

and impermanent,

4.

Channelization

caused loss of large

stable rock

substrates,

5.

Sedimentation

from

upstream tributary,

and

6.

Recurring

high

volume,

high velocity flooding.

Essentially

the

same

types

of

organisms

occur upstream and

within

the

seepage

zone.

Mobil

and

the

Agency

have

made the following

recommendation

for

conditions

of

the

Variance:

Ammonia

Nitrogen

Monthly

Average

27

Maximum

45

Un-Ionized

Ammonia

No limitation

Fluoride

Monthly

Average

4.5

Maximum

10

TDS

Monthly

Average

1300

Maximum

2000

59-400

---

—5*

Monthly

Average

500

Maximum

685

The

Agency

recommends

a

three—year

variance

to

allow

more

rapid

review

of

the

impac-t

and

possible future

improvements,

Mobil

requests

five

years.

Based

on

the

record

in

this

case

the Board

finds there is no

reasonable

technology

available

for

compliance

and that to

require

immediate

compliance

would

impose an arbitrary

and

unreasonable

hardship

in

view

of

the

limited

evidence of

environmental

harm.

The

Board

will

grant

a

variance from the

applicable

regulations.

This

variance will be for the

shorter

period

to

allow

rapid

re-evaluation,

should any additional

restrictions

prove

necessary.

In

its

February

3,

1984

Amended

Petition for Variance,

Mobil

requests

relief

from

“sulfate

limitations applicable to Outf

ails

001

and

002,..”

(Am,

Pet,,

¶A3)..

Outfall 001

is

never addressed

in

the

remainder

of

the

petitions,

supporting documentation

or

Agency

recommendation.

The

Board presumes that inclusion

of

Outfall

001

in

that

one

sentence

was a typographical error,

This

Opinion

and

Order

in

no

way

addresses or grants relief for

Outfall

001.

This

Opinion

constitutes

the Board’s findings of facts

and

conclusions

of

law

in

this

matter,

ORDER

M-obil

Chemical

Company

is

hereby granted a

variance, as of

November

15,

1983,

applicable

to Outfall 002

only,

from 35

Ill.

Adm.

Code

302,212

and

302,208

(fluoride,

total dissolved solids,

and

sulfate

only),

subject

to

the

following

conditions:

1.

This

variance

shall

expire July 1,

1987.

2.

Water

quality

at

Outfall

002

shall not exceed the

following

limitations

(in mg/i):

~1

~e

Maximum

Ammonia

Nitrogen

27

45

Un—ionized

Ammonia

No limitation

No limitation

Fluoride

4.5

10

Total

Dissolved

Solids

1300

2000

Sulfate

500

685

3.

Mobil

Chemical

Company

shall

at all times

maintain

and

operate

its

existing

bypass/sump/collection

system

in

such

a manner as to achieve

optimal

performance.

This

shall include

measures

to prevent or

alleviate

the

buildup

of silt

in the

pumping station.

59-401

---

—6—

4.

Mobil

Chemical

Company

shall

perform

sampling

and

analyses in accordance with NPDES

permit

IL

0032182.

In addition, un-ionized ~—onia shall be monitored

or calculated at the same

frequency

as total esmonia

nitrogen.

5

•

Mobil Chemical Company shall thoroughly investigate

any and

all possible technologies for achieving

compliance, and shall file a report of its findings

with the Agency’s Compliance Assurance Section on

July

1, 1985.

This report shall also

detail

the

steps to be taken to achieve compliance by

July 1, 1981.

6

•

Within 45 days of the date of this

Order,

Mobil

Chemical. Company shall execute

a

Certification

of

Acceptance

and

Agreement

to

be

bound

to al1 terms

and

conditions

of

this

variance.

Said

Certification

shall

be

submitted

to

the

Agency

at

2200

Churchill

Road,

Springfield,

Illinois 62706.

The 45—day

period

shall

be

held

in

abeyance

during

any

period

that

this

matter

is

being

appealed.

The

CERTIFICATION

I,

(We) ________________________________, hereby accept

and agree to be

bound

by all terms

and

Order of the Pollution Control Board in

PCB

83—166, August 22,

Title

IT IS SO ORDERED

I, Dorothy N. Gunn, Clerk of the Illinois Pollution

Control

Board,

hereby ce5~/ythat the above

Opinion

and Order

was

adopted

on

the

L3.

day

of

,

1984 by a vote

of

&-n

47a-tatbt

tn.S~

Dorothy M.~fln,

Clerk