Ir1T~INOIs POLLUTION CONTROL BOARD

April 5, 1985

IN

THE MATTER OF:

JOINT PETITION OF THE CITY OF

)

PONTIAC AND THE ILLINOIS

)

ENVIRONMENTAL PROTECTION AGENCY

)

PCB 83-231

FOR EXCEPTION TO THE COMBINED

SEWER OVERFLOW REGULATIONS

)

ALAN M. SCHROCK, ASSISTANT CITY ATTORNEY, APPEARED ON BEHALF OF

THE CITY OF PONTIAC: AND

DAVID L. RIESER APPEARED ON BEHALF OF THE AGENCY.

OPINION AND

ORDER OF T~IE BOARD (by 3. Anderson):

This matter

comes before the Board on the December 14, 1983

-ioint petition o~

the City of Pontiac (City) and the IEPA (Agency)

for an exception to 35 Iii.. Mm. Code 306.305(b) of the Board’s

combined sewer overflow (CSO) ~egulations

which provides that

“Additional flows i.e. not dry weather flows or

first flush storm flows, as determined by the

Agency hut not less than ten times the average dry

weather flow Eo.r the design year, shall receive a

minimum

of

primary treatment and disinfection with

adequate retention time”.

Th~ joint petition alleges that the City’s

existing

CSO discharges

have minimal impact on Vermillion River water quality, and that

construction of CSO treatment facilities at an estimated cost of

$1.1 million would produce little benefit.

This

case

is the first utilization of the Board’s CSO

“Exception Procedure”, 35 Ill. Adm. Code 306.350 et seq. Hearing

in this matter was held on February 15, 1984, at which some

members of the public and press were in attendance. Testimony

and exhibits

(Exh. 1-5) were presented by the parties at hearing.

Information not available at the time of hearing was filed in

letter

form

by the Agency March 8, 1984; this letter, concerning

the

City’s status

on the Agency’s restricted status or critical

review lists, is hereby accepted as Exhibit 6, and the Board

Orders

referred to therein are incorporated by

reference as

if

fully set forth. No other written submittals or comments con—

57-359

---

cerning this

matter

have been received. This matter is being

given expedited consideration by the Board

*

as requested in the

petition

and at hearing,

so as to improve the City’s chances

of

receiving a 75 federal construction grant.

THE PONTIAC TREATMENT PLANT AND ITS CSO DISCHARGES

The City presented five witnesses at hearing: Mayor Dale

Campbell, City Administrator Robert Karls, Department Head for

the Sewer Department David Sullivan, Pontiac’s engineering con-

sultant George A. Farnsworth of Farnsworth & Wylie, and Glenn 0.

Chenoweth, who has resided since 1951 about 1½ miles downstream

of the Pontiac sewage treatment plant (STP) in a home about 30

feet from the bank of the Vermillion River (R. 23—25, Exh. 1).

The Agency presented one witness, Toby Frevert, an engineer in

the

Agency’s Division of Water Pollution Control, whose duties

include

coordination of CSO exception applications and analysis.

As much of the testimony related to the petition itself (Exh. 4)

and exhibits submitted therewith (Exh. 2), hearing testimony will

not be separately set forth, hut will instead be referenced as

appropriate.

The City of Pontiac, Livingston County, population 12,400 is

located at the junction of Interstate 55 and Illinois Route 116

about 100 miles south of Chicago. The

Vermillion River

flows

from east to west through the center of the City. Malor local

industries/institutions are Caterpillar Tractor Company, Kreger

Printing, Interlake Steel Company and an Illinois State Correc-

tional Center. The City is seeking relief from Section 306.305(b)

which would require that the City construct combined sewer

overflow pumping, grit removal, primary settling and disinfection

facilities

to treat

excess storm flows up to 11.7 MGD.

The City is served by 7.9 miles of separate sanitary sewers

and 25.5

miles of combined storm and sanitary sewers all col:1ect-

ing wastes

from

3300 sewer users and draining 1400 urban acres.

Five sewer interceptors,

having a total capacity of 20.1 MGD,

transport sewage to the treatment plant. The plant provides

three—stage

treatment

and disinfection for dry weather flows and

*The

Board

wishes to note that the parties have greatly

facilitated the Board~sconsideration of the first of these CSO

cases by the

manner

in which the presentation was made. The

joint

petition itself properly included the engineering reports,

stream use

and water quality data, etc. supporting the con-

clusions in the petition.

Each party made its necessary and

knowledgable resource persons available for explanations and

questioning at hearing, avoiding the need for additional hearings

to plug record gaps. Future CSO exception petitioners would be

advised to examine the record in this matter.

57-360

---

primary treatment and disinfection for excess MCD flow. Design

capacities are

2.13

MGD average and 4,3 MGI) maximum for dry

weather flow and up to 4.3 MGD excess flow, The plant is located

on the west side of the City on Old Route 66 and discharges

treated effluent to the Vermillion River.

There are four combined sewer overflows from the City’s

sewer system. (See Exh. 3). Two overflows (003 and 004) located

near the treatment plant have a combined capacity of about 9 MCD

(14 cfs)

and

bypass storm flows fro~nthe interceptors directly to

the Vermillion River. The other two overflows (004 and 005)

having a total capacity of 5.9 MCD (9 cfs) are located in the

upper part of the sewer system on the north side of the City and

bypass storm flow to a storm sewer which discharges to the North

Ditch, a drainage ditch tributary to the Vermillion River.

Overflow points 004 and 005 were constructed about

3

years ago to

bypass flows from the North Street sewer, a 100 year old 2’ x 3’

elliptical brick sewer. Overflow points 003 and 004 have been in

existence for “many years,” with NPDES 003 also being a bypass

mechanism for the North Street sewer.

Studies of sewer hydraulics which have been confirmed by

field sampling show that overflows do not operate until the wet

weather first flush has passed. (See Exh.2, Section 3.3, Exhibit

A.)* For comparison to overf low capacities

cited, the Vermillion

Rivers’s mean annual flow is about 380 cfs. During normal dry

weather, flow ranges from 20 to 60 cfs. Typical flow in the

North Ditch, a srrtall, man-cut drainage ditch with intermittent

flow, is about 5 cis. (See R. 37—40, Exh, 2, Exhibit C.)

The overflows are not monitored continuously, but it is

known that bypassing begins at the two overflows located near th~

plant (003 and 004) during rains ranging from 0.5 to 1.0 inch/hour.

One of the upstream overflows (005) will

operate at about

0.3

inch/hour rainfall and the other (006) rarely operates.

Exhibit 2, Appendix

to Exhibit A gives an analysis of

the

typical first flush

and CSO

pollutant load. The upstream over-

flow is usually quite dilute with BOD less than 50 mg/i and

suspended solids less than 150 mg/i (see Figure 4—2B Appendix to

Exhibit A). The overflows near the treatment plant after the

first flush has passed show BOD around 100 mg/i. Suspended

solids are 400÷mg/i but the volatile solids level of about 40

indicates that this is mostly inorganic grit. (See Figure

4—2A

Appendix

to Exhibit A.)

*Recere~c~sto Exh. 2 will

contain references to a letter

exhibit within the group exhibit, as this

reflects the parties’

original :Ldentiiication scheme.

57-361

---

—4,,

The City’s treatment plant was upgraded in 1976 under the

old “PL660~ grant program. Because that plant was designed

before

the major rule

changes

of PL92—500,

that expansion did not

include facilities for nitrification and the required

amount

of

CSO treatment,

On February 23, 1979, the City received an Agency “notice of

critical review,” because it had reached

95 of its hydraulic

load capacity

of 21.3 MCD, It was in fact

placed on critical

review ApriL 6, 1979. On March 6, 1981, the

Agency issued a

“notice of impending restricted status”,

because of lack of

hydraulic capacity, organic overloading in

excess of the 16,000

P.E. design capacity, and failure to meet certain

interim ‘SOD and

TSS limitations. Treatment plant discharges

were polluting the

receiving stream sewer surcharging,

and basement backups were a

common occurrence, particularly along

the North Street sewer (see

Exh. 5, and Drake v, IEPA, PCB 81-54, Oct.

22, 1981 and Bergman

v. IEPA, PCP, 81—67, Sept. 3, 1981,)

Since 1981, the City has taken major steps to turn around a

rapidly deteriorating STP and sewer situation. Since 1981, the

City has spent $831,000 to separate combined

sewers (R. 18). An

ongoing program for the yearly cleaning of all combined sewers in

the months between May and November was instituted, at a cost in

1981 of $57,000 (H. 79, 96). iBy contrast,

sewer

cleaning in

other commun:Ltias is done on a 3 to 5 year rotation basis (R.

86)), The City believes that its sewer

separation program,

in

combination with its

street and sewer cleaning efforts, have

reduced

the occurrences

of sewer surcharging and basement back-ups

due to

plugged sewers,

The

City notes,

however, that some base-

ment

flooding continues to occur due to the

nature of the Pontiac

system

and it~s

relation to the river,

Many of the areas served

by combined sewers

are

in the

floodway

or floodplain, and so are

flooding

when the river backs up into low-lying,

flat sewers (H.

82, 88—92).

Pursuant: to

permits

issued in July,

1981, the City has made

certain ~interim~r improvements

to

its STP,

including expansion of

its

capacity

to handle

organic loads. The City currently remains

on critical review

with

1470 P.E, of capacity remaining. The

Agency notes that

the City may apply for

review of its status by

submitting additional

capacity

and influent

information (Exh.

5).

The City has,

meanwhile,

completed

design work for additional

upgrading

of

its

STP. The City

Step

I Facilities Plan for Phase

II was approved by the Agency and certified

to Region V USEPA on

September 30, 1983. This expansion will cost in

excess of $8

million.

Under the assumption that is would be eligible for a 75

federal construction grant (rather than the 55 grant available

57-362

---

—5-

after October 1, 1984), the

City petitioned

the

courts

for per—

nission to hold a special election to get authority to issue

bonds for the 25

matching

funds

-e

$2 million.

On February 6,

1983, the Agency advised the City that no grant

funds

were

available to it in 1983

because

of its priority number. The

referendum was nonetheless held on February 7, 1983, and

approved

by a vote of 882-119. (The City notes that it would lack legal

authority to issue

bonds

to raise a 45 match,

even

with voter

approval, because of restrictions on total bonding levels in

relation to the City’s total assets). The City is nonetheless

proceeding with finalization of design work

and

other pre—grant

activities, since, in the

words

of Mr. Frevert;

V~Jj

is still a horse race amongst the munici-

palities in

the

State of Illinois for grant

funds..

•

The

name

of the game is to have your

planning work done, and to have your local funding

available, have your design work done,

and

have

your plans and specs ready to

go, so

you

are in

the starting gate, and realistically are in com-

petition for those funds when they

become

available.’

(R.

105—106)

The approved STP

improvement

plan (described in Exh. 2,

Sections 3.1 and 3.2 of Exhibit A) proposes construction of

a.

kdditional capacity for three-stage dry weather flow

treatment

(average of 3.45 MGD up

to

maximum

of 8.40

MGS).

b. Capture

and

storage of ‘first flush’ (0.41 MG) for

treatment later during

dry

d. Sludge stabilization and disposal.

e. CSO treatment of up to 11.7

MCD

above maximum

dry

weather flow for compliance with Section 306.305(b).

The construction (capital) cost of the

proposed

improvements

a. Dry weather flow treatment, nitrification,

b. Additional CSO treatment to meet

Section 306.305(b)

e,zoo,ooo

---

The estimated annual cost of sewer maintenance and the

operation and maintenance (O&M) of the existing and proposed

treatment plant shown in Exh, 2, Exhibit B are as follows.

Figures shown do not include financing and

capital costs.

a.

Existing treatment plant and sewer

$470,000/yr.

system O&M

b. Additional O&M of proposed dry

80,000/yr.

weather flow treatment, nitri—

fication, first flush capture and

sludge treatment

c.

Additional

CSO treatment O&M

50,000/yr.

Total Annual O&M

$600,000/yr.

The estimated

cost of financing of the city’s share of the

proposed Phase II project costs is as follows.

Costs shown

assume a 25 percent city share financed with a

20—year revenue

bond issued at

11 percent interest requiring 25 percent annual

coverage of principal

and

interest.

a,

Additional

dry weather flow

$275,000/yr.

treatment, nitrification,

first

flush

capture

b.

CSO treatment

45,000/yr.

Total Annual

Financing Cost

$320,000/yr.

The above shows

that the relief sought by the Petitioners to

avoid constructing the CSO treatment facilities

would

save

$1,100,000

in

construction

costs and $95,000 per year in O&M and

financing costs.

ENVIRONMENTAL IMPACT OF THE DISCHARGE

The parties~ conclusions that existing storm overflows from

the Pontiac

combined

sewer system are having minimal impact on

Vermillion

River

water quality, and that

stream

use is not beina

restricted~ are based

on reviews

of existing water quality data,

as well as

field observations by Agency personnel and George

Farnsworth,

the

City~s consulting engineer.

Historical data

available, as

summarized at p. 7 of the petition (Exh. 4) reveals

the Eollowing (references

are to

letter exhibits within Exhibit

2):

~‘a.

Exhibit

D summarizes existing stream biological data

from

various stations in the Vermillion

River basin.

Researchers noted consistent

minor violations of

ammonia,

boron and lead standards up to

1980.

Fisheries

data showed good

diversity of

species and

57-364

---

—7-

high numbers of sport and non-tolerant species present.

No conclusion on basin condition

was

made because of•

limited data.

(This report was

prepared

as part of the

b. Exhibit E is water quality data for land collected by

the Streator, Illinois water treatment plant intake

located 25 miles downstream from Pontiac. Streator is

the nearest point

downstream

where the River is used

for domestic water supply. There appears to be no

impact on raw water quality at Streator’s intake from

Pontiac’s discharges.

*

c. Exhibit F is a compilation of available water quality

data for stations near Pontiac (furnished by the U.S.

Geological Survey and the Agency. Stream water

quality violations noted in Exhibit I are sumearized in

Exhibit F. No correlation in violations

with

Pontiac

CSO

events

is evident

and

violations are minor. (No

data is

presented for 1982-1983; water quality

standards violated are usually those for total iron and

d.

Exhibit C is a compilation of available river flow data

at Pontiac from 1942 to 1982 furnished by the U.S.

Geological Survey and the

Agency. Average flow of

record is 380 cfs. Extremes of flow are

one

no—flow

event in 1953 and 14,500 cfs in 1980.’

Visual inspections of the areas for about 300 feet below

each CSO outfall and the treatment plant outfall were made by Mr.

Farnsworth on June 21, 1983 (R. 48—49, Exh. 2, Exhibit A, S4.1).

Some

evidence of sludge deposition was discovered near the

STP

outfall.

However, the source of that sludge is believed to be a

floor drain connected to the outfall sewer, and the City intends

to correct that design flaw in the plant expansion project.

Evidence of sludge deposition was found in the first 30 feet

of the river downstream of Outfalls 003 and 004,

but

the

deposits

were shallow (less than 2 inches deep) and difficult to differ-

entiate from natural stream silt. Odor was evident only when the

deposits were

disturbed.

Some

small amount of CSO—related

‘trash’ was discovered near Outfall 003 for about 10 feet down-

stream,

but

it was quickly collected.

*It

should additionally be noted that Streator

pumps

water

from the Vermillion into a side channel reservoir. Water from

the reservoir is then pumped into the water purification plant

for treatment (R. 112).

57-885

---

In

the

area of the North Ditch outf ails, one sludge

deposit

less than 2

inches deep and roughly 5 feet by 6 feet

was

dis-

covered immediately downstream of the outfall, Ditch flow was

low, with isolated pools evident

(from which

children were catch-

ing minnows).

On September 14, 1983, two Agency field biologists inspected

the

river and the North Ditch (Exh, 2, Exhibit C). Their report

concluded that conditions in the river have not changed since a

1976 biological

survey indicated “unbalanced” stream conditions.*

As to the North Ditch, at a sampling point just downstream

of Outfalls 005 and 006, no sludge was found but the stream

condition

was “semi—polluted.” However, sludge and oil was found

at a sampling station upstream of the outfalls where the stream

condition was also semi—polluted. The biologists concluded that:

“The two CSO’s that discharge directly to the

Verrnillion River appear to have no more adverse

effect on the River than does the STP discharge.

Similarly, the CSO’s on North Ditch also appear to

have no adverse effect on the Vermillion River

although there does seem to be some degradation of

North Ditch. Because of these findings, we feel

that the complete treatment

of

the Pontiac CSO’s

would not significatly improve the water quality

of the Vermillion River.” (Exh. 2, Exhibit C)

~t hearing, it was stated that is was the “definite opinion” of

the authors of the

report that the water quality deterioration in

the North

Ditch was not attributable to

the

City’s CSO overflows,

but to some other upstream source (R. 106),

Uses of the Vermillion River and the North Ditch were dis-

cussed both by the City and the Agency. In addition to the

River’s use as a public water supply for Pontiac and for down-

stream Streator, it provides an “aesthetic quality” for the

residential homes along its banks, and a “desirable and utilized

recreational opportunity” (R. 103). The area near the Vermillion

River CSO outfalls

has become an increasingly popular fishing

spot, as, in the last 5 years, the type and quality of fish

caught have improved; shallow ponds in the North Ditch are a

popular source of minnows for bait. The River is used for

canoeing, although it is too shallow ~or swimming. Mr. Chenowith,

a 30—plus year resident of a river

bank

home a mile and a half

*In this classification system, based on analysis

of~

the henthic macroinvertebrate population in a

water body, the

“best” stream condition is “balanced”, followed by “unbalanced”,

“semi—polluted”, and “polluted”.

57-366

---

—9—

downstream of the STP outfall, and a longtime outdoorsman and

conservationist, characterizes the River as currently “nice and

clear”, and “look (ing) real good” (R. 28, 26).

Given all of the above, the Agency, in its concluding

remarks, noted that it feels that the Vermillion River is a

valuable resource worthy of protection in the way of additional

improvements to the City’s STP and control of first flush.

However, capture and treatment of ten times dry weather flow at a

capital cost of $1.1 million would not result “in a justifiable

improvement or return in water quality” (R. 104).

THE RESOLUTION

The Board finds, based on the uncontroverted evidence in

this record, that the granting of an exception to 35 Ill. Mm.

Code 306.305(b) has been justified. This determination is based

on the general improvement to water quality attributable to

upgrading of the City’s STP, the Agency’s assessment of the

minimal environmental impact attributable to the City’s CSO

discharges, the high cost of 10 times dry weather flow capture

and treatment facilities, particularly given the City’s grant

funding prospects. However, the question arises as to whether

this exception should be granted without conditions.

Much discussion at hearing centered around the City’s com-

bined sewer cleaning program, and the effect it might have on

CSO discharges. As aforementioned, the program was instituted,

not to control the strength of first flush storm flows, hut to

eliminate basement back ups resulting from sewer blockages.

According to Mr. Sullivan and Mr. Farnsworth, the investment in

metering and sampling equipment necessary to determine the effect

of the program on CSO flows would be substantial, so that no

quantitative evidence has been gathered~ Their qualitative

observation is that there is substantial solids removal. While

Mr. Farnsworth believes that “a rainfall a month would keep the

sewers pretty clean”, nonetheless annual combined sewer cleaning

is “more or less insurance”. It is, however, Mr. Farnsworth’s

conclusion that, even if the City did not perform sewer cleaning,

the impact of grant of an exception from the ten times dry

weather flow capture and treatment provision would be the same

——

minimal (R. 84—85, 63).

When inclusion of a sewer cleaning requirement was discussed

at hearing, the City stated that is has no specific objections to

such a condition, based on its intent to continue the program for

its own purposes. To the extent there is an objection, it relates

to the removal of discretion from a City administration “twenty

years down the road” (R. 121).

57-367

---

The data preuented to the hoard reflects observations and

estimates based on cleaning of the combined sewers. The Board

therefore believes that, to maintain the status quo, it is the

better course to require continuation of the sewer cleaning

program despite lack of data quantifying its effects, and will

so order. However, to provide the City with a measure of flexi-

bility, the Board will order only that the City clean its com-

bined sewers once every three years, in line with the practice in

other communities. The Board does, however, encourage con-

tinuation of annual combined sewer cleaning.

This Opinion constititutes the Board’s findings of fact and

conclusions of law in this matter.

ORDER

The City of Pontiac is hereby granted an exception from 35

(11. Mm. Code 306.305(b) requiring treatment and disinfection of

10 times dry weather storm flows, provided that the City cleans

its combined sewers at least once every three years, in the manner,

described in the hearing in this matter on February 15, 1984.

IT IS SO ORDERED.

I, Christan L. Moffett, Clerk of the Illinois Pollution

Control Board, hereby certify that the, above Opinion and Order

was adopted pn the~’~— day of

~-~Li

,

1984 by

a vote of

_j~(~

.

V

Illinois Pollution

57-368