ILLINOIS
POLLUTION CONTROL BOARD
April
1,
1987
IN THE MATTER
OF:
)
THE SINGLE PETITION OF
)
THE CITY OF PERU
)
FOR EXCEPTION TO COMBINED
)
PCB 86—1
SEWER OVERFLOW REGULATIONS
MR.
DOUGLAS
3. SCHWEICKERT APPEARED ON BEHALF OF THE CITY OF
PERU;
MR.
THOMAS DAVIS APPEARED ON BEHALF CF THE ILLINOIS ENVIRONMENTAL
PROTECTION AGENCY.
OPINION AND ORDER OF THE BOARD
(by 3.
Theodore Meyer):
This matter comes before
the Board upon a January
2, 1986,
petition
filed by the City of Peru (Peru)
seeking an exception to
35
Ill. Adm.
Code 306.305
(a) and
(b)
of the Board’s combined
sewer overflow (CSO) regulations.
A public hearing was held
in
Peru,
Illinois on June
4,
1986.
The Board received additional
information
from Peru on June
18 and September
3,
1986 and
February
9,
1987.
The Illinois Environmental Protection Agency
(Agency) submitted comments to
the Board
on September
22,
1986.
CSO REGULATIONS
The CSO
regulations are contained
in
35
Ill.
Adm.
Code
306.302, et seq.
Section 306.305 provides as
follows:
All combined sewer overflows and treatment plant bypasses
shall
be given sufficient treatment
to prevent pollution,
or
the violation of applicable water
standards unless an
exception has been granted
by
the Board pursuant
to Subpart
D.
Sufficient treatment shall
consist of the following:
a)
All dry weather flows,
and the
first flush of storm flows
as determined
by the Agency,
shall meet the applicable
effluent standards;
and
b)
Additional flows,
as determined by the Agency but not
less than ten times
to
sic
average dry weather flow
for
design year,
shall
receive
a minimum of primary treatment
and disinfection with adequate retention time;
and
c)
Flows
in excess
of those described
in subsection
(b)
shall
be
treated,
in whole
or
in part,
to
the extent
77-11
—2—
necessary
to prevent accumulations of sludge deposits,
floating debris and solids
in accordance with 35 Ill.
Adm. Code 302.203,
and
to prevent depression of oxygen
levels;
or
d)
Compliance with
a treatment program authorized by the
Board
in an exception granted pursuant to Subpart D.
Subpart D allows
the discharger
to file
a petition for
an
exception either
singly,
or jointly with the Agency.
The Agency
testified
that Peru did take all the necessary steps
to qualify
as joint petitioners with the Agency,
including submitting
a
Phase
I Study in June,
1983 and
a Phase II Study in December,
1984.
However,
the Agency chose not to co—petition with Peru
because of the unique geographic situation that exists at Peru,
the
fact that sludge
and sewer—related debris were apparent at
various points
in the ravines which receive the CSO discharge,
the sheer number
and frequency of overflows and the fact that the
comparatively low cost improvements planned by Peru will,
for the
most
part, have no
significant impact on either the number or
frequency of overflows
(R.
at
11).
The Agency also wants
to see
two additional improvements at
a combined cost of $155,000 added
to Peru’s proposed project.
(R.
at 11—13). The Agency also
testified that
it
is not opposing
or disputing any of the
arguments raised
in Peru’s single petition and that
it feels that
Peru is the only single petitioner who not only aggressively
pursued
a joint petition but also has
a reasonably sound
basis
for
a CSO exception
(R. at 10—11).
In order
for
a discharger
to receive
a CSO exception,
a
certain level
of justification
for the exception
is required
to
be submitted.
This level
of justification differs depending on
whether the discharger
files
a single or joint petition
for CSO
exception.
The level
of justification required
of
a joint
petition is
set forth
in Section 306.362 which provides for
a
demonstration under
Secti.on 306.361(a)
(i.e.,
minimal discharge
impact) which
is not available
to single petitioners.
However,
Peru as
a single petitioner,
justifies its claim for
a CSO
exception based on Section 306.361(a).
Notwithstanding this
shortcoming,
the Board
finds that Peru has satisfied
its
justification burden
for
the
following reasons.
Section 306.361(d),
applicable
to single petitioners under
Section 306.362, provides that
a discharger may establish that
because special circumstances exist,
an evaluation of CSO—related
impacts would be
inapplicable for reasons of irrelevancy or the
expense of data collection
in relation
to the relevancy of
the
data.
In
this regard,
Mr. Toby Frevert
of the Agency testified
that he advised Peru
to refrain
from doing
a detailed CSO impact
study
(i.e.,
a Phase
III Study)
because
he felt that the results
77-12
—3*
obtained would
not justify the expense.
(R.
at 81).
He based
this conclusion on
a recently completed
study on the water
quality
impacts
of
CSOs
in
Peoria
in
which
it
was
concluded
that
because
of
the
shoreline,
rapid
current,
deep’
water
depth
and
velocities of the Illinois River, there was little detectable
CSO—related
impacts on the Illinois River.
This study cost
approximately $750,000.
He testified
that in his opinion he
would not expect dramatically different results
in Peru.
(R. at
82
Based
on this testimony,
the Board concludes that a Phase
Ill—type study of CSO related impacts on the Illinois River
in
the Peru area would be of little utility in relation to
the costs
involved.
In
other
words,
the
cost
and
time
involved
in
having
Peru complete
a Phase III Study would not be justified
in
relation
to
the
results
obtained.
In
addition,
the
Board
does
have data on CSO—related impacts which were provided
in Peru’s
Phase
II Study
-~—
Preliminary Stream
Inspection
——
which
enables
the Board
to adequately evaluate the CSO problem
in Peru and
the
related impacts on the receiving stream.
For
these reasons,
therefore, the Board
finds that Peru has satisfied
its
justification
burden
pursuant
to
Section
306.361(d)
and
while
such
justification
should
have
been
established
in
the
petition
itself,
the
Board
believes
that
in
the
case
of
Peru,
such
justification, as
a practical matter, could only be supplied at
hearing.
ENVIRONMENTAL IMPACT
The City of Peru
is located along
the north bank of the
Illinois
River approximately five miles downstream from the
Starved
Rock
Lock
and
Dam.
The
City
operates
a
secondary
waste
water treatment plant
(WWTP) built
in 1939 which operates under
NPDES permit No.
1L0030660.
The plant has
a maximum rated
capacity
of
4.53
million
gallons per day (MGD); during 1985 the
average
daily
flow
through
the
plant
was
2.7 MGD.
R.
at 18—19..
The City has a population of 11,000 which
is served by
38 miles
of combined sewers and
11 miles of sanitary sewers.
The major
combined sewers are the Illinois River
Interceptor, parallel
to
the Illinois river,
and two interceptors located
in ravines known
as
the
West
Ravine
and
the
East
Ravine.
Each
ravine
contains
an
intermittent
stream;
the
West
Ravine
drains
to
the
Illinois
River
and
the
East
Ravine
drains
to
the
Illinois
and
Michigan
Canal
(I
& M Canal).
Overflows
from
the
combined
sewer
interceptors
discharge to these streams
or
to the Illinois River.
Including
overflows
and
bypass
at
the
WWTP,
the City has
27 CSO outfalls.
Each
of the overflows
in question consist of a manhole on
the
interceptor with
an overflow pipe protruding through the wall
of
the manhole
to the receiving stream.
The Illinois River
Interceptor has eleven overflows and the
WWTP bypass
along
its length of approximately 7,715
feet..
These
77-13
-.4—
overflows all discharge to the Illinois River
and are located
in
an area zoned
for manufacturing.
Human contact activities
include water
skiing
and
fishing.
The river
supports white bass,
walleye,
sauger, catfish,
as well
as rough
fish.
The Illinois River
through Peru
is approximately 600
to 800
feet wide and,
in places,
30 feet deep.
The flow in the river at
Peru is approximately 35,033 cubic feet per second.
The City has
estimated the dilution ratio
for
a once
in one year rainfall
event at the Illinois River
Interceptor
at
293
to
1.
The impact
on the Illinois River
is asserted
to be minimal because of these
large dilution ratios.
In addition,
the Peoria Phase III
Study,
asserted
to be relevant to the City of Peru by the Agency,
demonstrated that the potential
impact of periodic overflows on
the Illinois River
is minimal because
of the rapid current, deep
water depth, and velocity of the river.
P.
at
81—82.
Inspection of the overflows revealed
the presence
of sewer—
related debris at almost all
of the outfalls; however, the debris
was generally dissipated by the river within 25
feet.
Varying
odors were detected
at outfalls No.
3,
No.
4, No.
5,
No.
8, and
No.
9A.
Sludge buildups were present at points No.
8,
No.
9,
No.
9A and
the Wastewater Treatment Plant Bypass and Outfall
(No.
22)
but the river bed showed
no evidence of sludge buildup.
The
Agency would like
to. see construction of
a $55,000 extension at
point IR—No.
1 directly
to the river where
the amount of debris
accumulation has been large.
R.
at
47.
However,
the City
is of
the opinion that those water quality problems can be cured
by a
proposed screeining mechanism,
but stated
it would agree
to
install the improvements
if deemed necessary by the Board.
(R.
at
33).
The West Ravine Interceptor
has six overflows along
its
length of approximately 6,811
feet.
The interceptor can carry at
least
12.5 times dry weather
flow before overflow occurs which
Peru asserted
is sufficient
to handle first flush.
(R.
at 23).
The minimum dilution ration
in the ravine
is 408:1.
The City’s
consultant,
Mr. William Etzenbach,
testified that the ravine
is
very steep with very little room at the bottom for anything other
than the stream
itself.
The stream was characterized as
“pleasant appearing” although the stream bed has been scoured
down approximately three
feet to the limestone bedrock by the
introduction of some large diameter storm sewers into
the
ravine.
The ravine
is privately owned
over most of
its length
and because
of its steeply sided slopes
is not subject to further
development than already exists.
However,
the
interceptor passes
a City Park near
its upstream end which allows access by mainly
children seeking
to explore
its
upper length.
Similarly,
the
middle and
lower sections are accessible to those willing
to
climb
the steep banks.
Overflows occur between
10 and
20 times
per year depending
on rainfall volume and frequency.
P.
at
23—
24.
The City
has noted
the presence of some sewer borne debris
77.14
—5—
at some overflows and
in certain reaches
in the stream along with
wind or stream borne
trash.
Phase II study at
3,5.
In addition,
two overflows
(Nos.
4 and
6) terminate
in shallow pools which
contain some signs of sludge and sewer
related debris.
In one
pool
the sand and gravel was covered with
a
“thin black slimy
deposit smelling strongly of sewage.”
Phase II study at
4.
The
last overflow on the West Ravine discharges to
a pool,
approximately 30 feet by 6—8 feet and one foot deep.
Probing of
the pool bottom turned
the water “black and
turbid with decaying
sludge.”
Id.
at
5.
Downstream from this pool another pool
is
formed
in which
a cast iron trunk sewer
runs exposed.
At the
time of inspection
a hole cut
in
the pipe was allowing the
discharge of approximately 10 gallons per minute of raw sewage
into the pool.
The pool had
a “faint
smell
of fresh sewage at
the water surface, however, none from a distance of
6 feet
away.”
Id.
at
6.
Probing of the bottom revealed sewage sludge
in various stages of decay.
The pool
is approximately 100 feet
from the
Illinois River.
The City’s engineer has estimated that
it would cost approximately $100,000
to extend the West Ravine
Culvert to the Illinois River.
The Agency has indicated their
preference to see this extension made to enable any discharges
to
be readily assimilated by the river and thereby reduce aesthetic
and potential public health problems.
R.
at
13.
The City
believes that this expenditure would not be cost—effective since
there
is little or
no human contact
in this area, but will agree
to the
expenditure
if deemed necessary by the Board.
P.
at
33.
Turning
to
the
East Ravine Interceptor, nine overflows are
present along
its length of approximately
7,890 feet.
The
interceptor can carry at least 12.5
times dry weather
flow before
overflow occurs.
The minimum dilution ratio
in the stream
is
166:1.
The ravine and discharge areas are privately owned and
it
appears
that further development of the areas
is unlikely.
The
areas
in the vicinity of the
five upstream overflows are
accessible
to human contact due
to the local practice of
utilizing these areas
for nature walks and physical
fitness.
The
next three overflows are not as accessible, but human contact may
occur
for those willing
to negotiate the steep banks.
The
remaining overflow
is located
in
a manufacturing area and
discharges
to the
I
& M Canal approximately 800
feet upstream of
its confluence with the Illinois River.
The Petitioner states
that this area does not offer much potential for human contact
activities.
The East Ravine also carries
a great deal of storm
runoff and has been channelized.
However,
according
to Mr.
Etzenbach,
the water appears clear when flowing
and the stream
has
a good appearance.
This ravine
is also very steeply—sided
with little opportunity
for public access.
P.
at 24—25.
On
inspection trips, problems were noted
at the East Ravine Overflow
No.
2 where the pool and stream showed evidence
of sludge.
The
deposits continued downstream
to some extent
for
a distance of
75
feet
and ranged
in depth from
2 inches
to 1/8
inch.
Sewer
borne
debris was also
noted.
Deposits were also noted
at East Ravine
77-15
—6—
Overflow C—5, while sewage debris was found
at points C—5,
2A,
3,
3A and
4.
In its February
4, 1987 letter, however,
the City
states that at ER—2, ER—2A and C—5
the City reconstructed 600
feet of combined sewer
so that the overflows function
infrequently with
a “negligible effect”
on the stream.
February
4, 1987
letter at Par.
E.
The East Ravine Stream discharges to
the
I
& M Canal
which
is
a narrow back water
in the flood plain
of the Illinois River.
This area
is accessible but not
attractive
to public
use.
The outlet is narrow, approximately
one foot deep and has
a very weak, muddy bottom.
About 1,000
feet west of the mouth of the East Ravine Stream,
towards the
Illinois River, the canal
bed has been dredged out
to
a width and
depth which will accept barge traffic and this portion
is used as
a barge loading and unloading area.
The City states that
it was
unable
to
inspect the confluence of the creek and canal
for
unnatural deposits due
to its semi—frozen condition.
However,
from
a point
100 feet
from the confluence,
the water quality was
stated
to be quite clear with no noticeable color, odor or
organic matter.
The City states that since sludge deposits do
not occur upstream at the actual points of overflow
it seems
highly unlikely that sludge would be deposited in the canal
after
the stream had traveled approximately
2,000 feet.
A remaining outfall,
IMC—No.
1 which is located
approximately 1,000 feet west of the East Ravine Mouth also
discharges
to the
I
& M Canal
in
the barge loading area.
No
visible signs of debris were noted although probing of the black
silt resulted
in a slight sewage odor.
The City noted, however,
that a
similar odor
is characteristic of the river bed and
backwater lakes
in
the area.
Phase
II Study at 10.
COMPLIANCE OPTIONS
The City states that the cost
to undertake
a construction
program to achieve full compliance would
be $40,832,000 with an
annual cost including debt retirement and operations and
maintenance costs of $6,025.300.
P.
at
40.
This plan,
“Plan
A”,
would
include the construction of new interceptor sewers sized
to
carry a volume of 8.25 MGD of first
flush
for
a once
in one year
rainfall.
Facilities designed
to give secondary treatment
to the
first
flush volume and primary treatment
to 24.5 MGD would also
need
to be constructed.
Because of the size and location of the
current plant,
all
the flow to be treated would need
to be pumped
across
the Illinois River where the facilities would be
constructed.
Phase
II
Study at
14.
An alternative Plan
B would provide for all treatment at the
existing site north of the river.
Additional secondary treatment
capacity capable of handling 4.67 MCD of first
flush and
additional capacity
for primary treatment of 6.1 MG is
contemplated under Plan
B.
The cost
for plan
B
is $15,846,000.
Id.
at
21.
77-16
—7—
Under
Plan
C,
1.28 MCD of first flush would receive
secondary treatment and 6.1 MCD would receive primary treatment
at
a total cost of $11,297.00.
Plan D,
at a cost of $9,595,000
would
treat
the same flows as under Plan
C but would not involve
the same degree
of sewer
system rehabilitation.
Id.
at 25—31.
The plan urged by the City was explained at hearing and is
contained
in Exhibit
2C.
The City proposes to raise
the point of each overflow to
a
point at least
above the top of the pipe of the
interceptor.
A
bar screen will
be constructed within each overflow manhole which
will be subject to regular maintenance.
P.
at
30.
The City will
also renew broken pipe
in the trunk sewers to eliminate
inflow.
The West Ravine
Interceptor can carry at least 12.5 times average
dry weather
flow before
it discharges
to the stream.
However,
there
is
a bottleneck
at the West Ravine Overflow No.
6 caused by
reduction of the sewer pipe
to
12 inch.
The City will replace
this with
18 inch pipe so that the entire reach
of the sewer can
carry 12.5 times average dry weather
flow.
Along the Illinois
River Interceptor, flap gates will be constructed to eliminate
the possibility of river water
backing up into the system.
In
addition,
the overflow pipes will
be extended to the river’s
edge.
R.
at 31—32.
WWTP
improvements contemplated by the City
include the construction of a mechanically cleaned bar screen;
the construction of
a grit removal unit;
rehabilitation of an old
primary settling tank to treat
6.1 MGD;
flood proofing of the
WWTP; and provision of an alternate power source.
R.
at 36—38.
The proposed
improvements
to the WWTP and the city collection
system would cost $l,593.250.
On an annual
basis,
the debt
retirement
and the operation and maintenance costs would total
$1,287,000
and result in
a total
residential user rate of
approximately $8/month.
P. at 40.
The proposed improvements are
to be completed and
in full operation by July
1,
1988.
The City
believes that these improvements will
remove
93
of the
pollutants which would otherwise
be removed under
a full
compliance
plan.
R.
at
39.
The Agency questions the accuracy
of
this appraisal but does not have
a more accurate one.
P. at 61—
62.
The City estimates that the number
of overflow events will
drop from approximately 20
to
10 per year.
P.
at
54.
CONCLUSION
The Board shares the Agency concerns as
to whether the
proposed improvements will adequately control any environmental
impacts and believes that this situation warrants the imposition
of
a temporary exception until
such time as adequate
information
concerning
impacts after
the improvements are made can be
obtained.
The temporary exception will
be
timed
so
as
to allow
two years
from the July
1,
1988 completion date to gather
full
post—operational
data.
The Board will also retain
jurisdiction.
The Board also concludes that without extension of
77-17
—8—
the West Ravine Culvert, water quality violations are likely to
occur
in the inlet.
In addition,
the testimony indicates that
some human contact does occur
in this area.
Thus,
the Board will
direct that this extension be undertaken.
Concerning the
Illinois River Overflow No.
1,
the Board believes that the City’s
proposed construction of bar screens may eliminate the
accumulation of debris
in this area.
Accordingly, the Board will
not require implementation of this extension at this time but
will require periodic observation of this overflow point.
Should
these observations reveal
a continuing accumulation of debris,
the City may be
required
to extend this overflow point.
The
Board notes that the City will
be required
to file an amended
petition for permanent exception,
following which the Board will
schedule
a hearing.
The Board also finds
it is advisable
to provide for
constraints on expansion of the service area, but will allow the
City, by way of motion for modification,
to
request hook—ens
beyond
the residential
15 Population Equivalent
(PE)
limitation.
(See Par.
7
of Order).
The Board cautions the City
that it must submit justification data of sufficient specificity
for
the Board
to evaluate
the hydraulic effects of the new
loadings on the system,
including upstream—overflows,
and the
effects on the quality of the overflows.
The Board
notes that
the relief
is restricted
to those substantive requirements for
treatment of CSC5 and not
to relief from water quality
standards.
To assure that this issue
is clear,
the Board will
introduce into this Order language identifying
the scope of the
exceptions as granted.
In summary,
the Board
finds that,
taking
into account the factors contained
in 27(a)
of the Act, the City
of Peru has not justified a permanent exception,
but has
justified
a temporary exception with conditions.
ORDER
The City of Peru
(Peru)
is hereby granted a temporary
exception from the treatment requirements of
35
Ill.
Adrn.
Code
306.305(a),
as such provisions relates
to first
flush of storm
flows,
and
to
35
Ill. Mm.
Code 306.305(b),
for discharges into
the West Ravine Interceptor,
East Ravine Interceptor,
and
Illinois River
until July
1,
1990,
or until March
1,
1990
if the
City fails
to comply with paragraph
6 of this Order,
subject
to
the
following conditions:
1.
The City shall construct and operate
the
improvements
to
its wastewater collection system
and wastewater
treatment plant as described
in
Exhibit
C by July
1,
1988.
In addition,
the City
shall also extend
the west Ravine Culvert.
77-18
—9—
2.
The City shall
continue street and sewer cleaning
efforts
so as
to minimize the bypassing of solid
materials.
3.
The City shall
continue
its monitoring of the
combined sewer overflows on a weekly basis and
after every major rainfall and make written reports
thereon and take corrective actions as necessary.
4.
This grant of exception does not preclude the
Agency from exercising
its authority to require as
a permit condition
a CSO monitoring program
sufficient
to assess compliance with this exception
and
any other
Board regulations and other controls,
if needed, for compliance,
including compliance
with water quality standards
5.
This grant of exception
is not to be construed as
affecting
the enforceability of
any provisions of
this exception, other Board regulations,
or the
Environmental Protection Act.
6.
If, on or before March
1,
1990,
the City of Peru
fails to submit an amended petition for exception,
this temporary exception will terminate on March
1,
1990.
7.
Unless authorized by the Board upon petition for
modification of this Order, there
shall
be no
expansion of the
service area tributary to the
combined sewers except
for residential
hookups that
do not exceed
15 population equivalents
as defined
in
35 Ill. Adm.
Code 301.345.
8.
The Board will retain jurisdiction
in this matter.
IT
IS SO ORDERED.
J.
D.
Dumelle and
J. Anderson concurred.
I,
Dorothy
M. Gunn,’Clerk of the Illinois Pollution Control
Board,
hereby certify that the abo e Opinion and Order was
adopted on the /.A~
day of
________________,
1987,
by
a vote
Illino
Control
Board
77-19
