ILLINOIS POLLUTION CONTROL BOARD

August

1,

1985

CITY OF DIXON,

Petitioner,

v.

)

PCB 85—112

ILLINOIS ENVIRONMENTAL

PROTECTION ~:~UCY,

Respondent.

OPINION AND Oii:~ROF THE BOARD

(by W.J.

Nega):

This provisional

variance request comes before the Board

upon an August

1,

1985 Recommendation of

the illinois

Environmental Protection Agency (Agency).

The Agency recommends

that

a 15—day extension of

a previously granted provisional

variance be granted

to the City of Dixon

(Dixon)

from 35

Iii.

Adm. Code 304.141(a)

to allow time

for the completion

of

necessary repairs and modifications

to its wastewater

treatrnenL

facility~schlorine contact tank and chlorination system which

were begun

under

the provisional variance granted

in PCB 85-

103.

(Rec.

1;

see:

Opinion and Order

of July 11,

1985

in POL

85—103,

City

of Dixon

v,

IEPA),

In reference to the need for additional

time to complete

ti’e

requisite repair

work?

Mr. Karl Merbach,

the Superintendent of

the Petitioner~ssewage treatment plant, has indicated

in

n

letter

to the Agency that:

~Due to complications encountered during

repairs to our chlorine contact tank at

the

Dixon Sewage Treatment Plant, we will

be

unable

to meet

the provisional variance date

of July 31, 1985.

Our

estimation of the

time

it would

take for sandblasting and painting as

well as

replacement of plastic baffle sheeting

was not accurate,

We did not have the

personnel nor

the time to devote

our

full

workday

to this project as daily plant

operations

has taken

up much of the time we

had scheduled for this work.

We now have all the materials needed

to

complete

this prolect on the work site and

hope to be operational within

a week.

We are

requesting

that an extension

be granted

for

an

additinn~ififteen dave

to allow

us

to

cornpi~:ethis work,

The

fifteen

days should

give

enough

tin~e

and

cushion

to

allow

for

---

—2—

days when weather

or other emergency would

cause

us

to cancel work

for that day.

We have been working very hard

to complete the

much needed work

to the chlorination system as

this project has become

a learning

experience.

Any future projects of this type

should go smoother and more time efficient...”

(Rec.

6)..

The City of Dixon owns and operates

a wastewater treatment

facility (~TP)which has

a design average flow of

3.4 million

gallons per day

tMGD)

and consists

of raw sewage pumps,

comminutors, primary sedimentation, aeration tanks, grit

removal,

final sedimentation, disinfection, anaerobic sludge digestion,

sludge storage, and sludge drying

beds.

(Rec.

1).

The

Petitioner’s

WWTP

discharges

its effluent to the Rock River

pursuant

to its NPDES Permit No.

IL 0026450.

The Petitioner’s NPDES Permit provides that the city’s

wastewater

treatment facilities must meet final effluent limits

for

its main outfall 001 and

is required

to meet effluent limits

of

20 mg/i

for

biochemical oxygen demand

(BOD);

25 mg/i for

total

suspended solids

(TSS), and

a fecal coliform standard of 400/100

ml.

(Rec.

1).

During

the past year,

the Petitioner’s discharge monitoring

reports

to the Agency pertaining

to fecal coliform and chlorine

residual

in

its effluent have indicated the following

concentrations:

Month

Flow (MG))

Chlorine Residual (n~/l)

Fecal Coliform (#100 ml)

May, 1985

3,101

0.35

14

April, 1985

3.197

0.25

278

March, 1985

4.373

0.20

3,000

February, 1985

3.156

0.30

142

January, 1985

4.046

——

December, 1984

3.255

0.40

223

November, 1984

3.114

0.40

313

October, 1984

3.124

0.30

166

September, 1984

2.588

August, 1984

2.727

July, 1984

2.918

——

——

June, 1984

3.164

0.40

7

Average

3.230

0.33

138*

*G~JmetrjcMean

(Rec.

2)

Although

the Petitioner

added chlorination facilities

to

its

WWTP in

1967,

rio major repair work was done

to these chlorination

facilities

since their installation.

However,

the Petitioner has

indicated that,

~s an interim measure,

some repairs were

65~190

---

—3—

undertaken

in 1984 when they became necessary.

(Rec.

2).

r1~he

City

of Dixon intends

to discharge effluent from the final

3edimentation tanks

to the Rock River via its old outfai.l while

its chlorination facilities

are out of service.

The outfall

in

question

is

a

20

to

30

foot long open channel which

runs from

th’:

final sedimentation tanks to the Rock River.

(Rec.

2).

Because there

is no feasible way that chlorine can be added

to

the point where the Petitioner’s effluent leaves

the final

sedimentation tanks

and since

the open channel which will

be

utilized “does not allow

for sufficient contact time before

the

effluent reaches the river”,

there appears

to be

no practical

alternative

to discontinuing disinfection while

the Petitioner’s

chlorination facilities are out of service.

(Rec.

2—3).

However,

the Agency anticipates minimal environmental

impact

during

the

time period of

the

requested provisional variance due

to

the high dilution ratio of greater than 200

to

1

of river

water

to effluent.

Additionally,

the environmental

impact will

be minimized because there are no public bathing beaches

or

potable water supply intakes downstream from Dixon’s discharge

point to the Quad Cities.

(Rec.

3).

The Agency has noted that

the City of Dixon has applied for

a standard variance

in PCB 85—47

for relief from the provisions

of

35

Ill.

Adm. Code 304.120

(deoxygenating wastes)

until

it

installs new clarifiers at its WWTP, but emphasizes

that the

repair work that will be done on the Petitioner’s chlorination

facilities

is entirely separate and distinct from the repair work

delineated

in Dixon’s regular variance petition in

PCJ3 85—47.

(Rec.

3).

in reference to

the

instant provisional variance extension

request

in PCB 85—112,

the City of Dixon has indicated that:

(1)

it

has the necessary materials and manpower

to expeditiously

repair

and restore the chlorination facilities

at

this time;

(2)

the chlorination facilities do not presently provide adequate

contact

time;

(3)

the condition of its chlorination facilities

is

becoming worse;

and

(4)

if the requisite repair work

is not

promptly completed,

the chlorination facilities may fail

completely at

a time when weather conditions might be unfavorable

or when the appropriate manpower

is unavailable, thereby

resulting

in the chlorination facilities

being out of

service

for

a longer period

of

time.

(Rec.

3).

Accordingly,

the Agency has concluded that compliance

on

a

short—term basis with the requisite NPDES Permit standards would

impose

an arbitrary or unreasonable hardship upon the City of

Dixon.

Therefore,

the Agency recommends that the Board grant

the

Patitioner

a provisional variance extension from disinfection

requirements

for an additional 15 days beginning August

1,

1985,

or

until

the chlorination facilities are returned

to service,

whichever occurs

first.

65-191

---

—4—

Pursuant

to Section 35(b)

of

the Illinois

Environlnenta.L

~rotection Act,

the Board hereby grants

the provisional variance

as

recommended.

This Opinion constitutes

the Board’s findings of

fact

and

conclusions

of law

in this matter.

ORDER

The City of Dixon

is hereby granted a provisional variance

from 35

Ill. Adm.

Code 304.141(a),

subject

to

the following

conditions:

1.

This provisional variance shall

commence

on AugusL

1,

1985 and shall continue until August 15,

1985,

or

until

the Petitioner’s chlorination facilities

are returned

to service, whichever occurs

first.

2.

The Petitioner

shall contact Mr. Gary Reside

of

the

Agency’s Compliance Assurance Unit via telephone

at

217/782—9720 when the chlorination facilities are

returned

to service.

This telephone notification

shall

be

followed—up within

5 days with

a written

notification sent

to Mr. Gary Reside

at the

following address:

Illinois Environmental Protection Agency

Division of Water Pollution Control

Compliance Assurance

Section

2200 Churchill Road

Springfield, Illinois

62706

Attention:

Mr.

Gary Reside

3.

Within 10 days

of the date of the Board’s Order,

the Petitioner

shall execute

a Certificate

of

Acceptance and Agreement which shall

be sent

to

Mr.

James Frost of the Agency at the address specified

in item #2

of this Order.

This certification shall have the following form:

65-192

---

—5—

CERTIFICATION

I,

(We)

,

having

read the Order

of the Illinois Pollution Control Board

in

PCB 85—112 dated August

1,

1985,

understand and accept said

Order,

realizing that such acceptance renders all

terms and

conditions thereto binding and enforceable.

Petitioner

By:

Authorized Agent

Tit 1e

Date

IT

IS SO ORDERED.

I, Dorothy

M.

Gunn, Clerk of the Illinois Pollution Control

Board, hereby certify that the above Opinion and Order was

adopted on the

/4~

day of

_________________,

1985 by

a vote

of

7-O

L$7

Dorothy

M.

d’unn, Clerk

Illinois Pollution Control Board

65-193