ILLINOIS POLLUTION CONTROL BOARD
May 16, 1985
IN THE MATTER OF:
R82—7
PETITION FOR SITE—SPECIFIC RELIEF
BY THE CITY
OF ALTON
PROPOSED RULE.
FIRST NOTICE.
PROPOSED OPINION AND ORDER OF THE
BOAPSD (by 3. Marlin):
This matter comes before the Board upon the April
15,
1982
filing by the City of Alton
(City)
of
a proposal for site—
specific relief from 35
Ill, Adm.
Code 304.106
(offensive
discharges),
304.120(c)
(10/12 mg/i BOD/TSS effluent standards),
304.121
(400 mg/l fecal coliform bacteria effluent standard),
304.124
(15 mg/l total suspended solids effluent standard),
and
from the combined sewer overflow
(CSO) provisions
at Sections
306.302
(prohibition on expansion of
or new CSO service
areas),
306.303
(elimination of excess sewer
infiltration),
306.304
(prohibition on sanitary sewer overflows), 306,305
(treatment of
overflows and bypasses)
and 306.306
(compliance dates).
On May
13,
1982,
the Board entered an Order seeking
clarification of
the proposal from the City
(47 PCB 117).
A
merit hearing was held
in Aiton,
Illinois on February
14,
1983.
On October
12,
1984,
the Illinois Department of Energy and
Natural Resources
filed
its completed economic
impact statement
(EcIS) with the Board,
An economic impact hearing was held
in
Alton on January
17,
1985.
Final comments were submitted by
the Agency
on
April
15, 1985,
An engineer for the City submitted
comments on April
22,
1985 concerning
the operation of outfall
001,
yet the
City failed to provide
the Board with information
requested at the economic impact hearing as
to whether the
alternate Wood River Creek outfall was permitted by the Agency
and what effect. that information would have
on the proposed
language of the rule,
The City
is faced with three problem areas:
receiving
stream reclassification, CSO elimination
(dry and wet weather
*
The Board acknowledges
the work of
Kevin
F,
Duerinck, hearing
officer
for this rulemaking, who assisted
in drafting
this
Opinion
and Order.
~34~
105
2
flows)
and WWTP upgrade.
Prior to
1982,
the receiving stream for
the WWTP was considered
to be the Mississippi River even though
it discharged into Wood River Creek
(Creek)
approximately 1,000
feet from the Mississippi.
It
is now classified by the Agency
as
the Creek,
a low flow stream,
thereby imposing more strict
standards
for SOD and TSS,
The City requests relief from the
10/12 mg/l BOD/TSS and 15 mg/i TSS effluent standards
(15 mg/l
standard for the CSO discharges).
The City proposes
to meet the
prior
20/25 mg/i standards for BOD/TSS for
its W~1TPdischarge.
Besides reclassification difficulties, the City has a
CSO
problem.
There
are prohibited overflows from sanitary sewers
to
the Mississippi River.
In addition,
some dry weather
flows,
the
first
flush of storm flows
,
and ten times
the average dry
weather flow are not being sufficiently treated.
The Mississippi
River
inundates certain CSO areas when the river pool level
is
above elevat:ion
415,3
(Pet.
3)
Lastly to meet standards,
the WWTP must
be upgraded or the
sewer outfall must
be extended another
1,000
feet to the
Mississippi River proper,
The City’s wastewater treatment plant
(WWTP) provides
secondary treatment by the contact stabilization mode which
consists of settling and aeration tanks.
The WWTP was designed
for a population equivalent of 105,000 people,
an average design
flow
of 10.5 million gallons per day (MCD) and a peak design flow
of 26.25
r4GD.
The service area includes Alton, part of Godfrey
Township,
and Bethalto,
Discharge
is
to either permitted outfall
001
or
to an unpermitted outfall
into the Creek near the WWTP
5,000 feet from the River depending
on the elevation of the
Mississippi River
(see Pet, Exh,
13).
During normal river
stages,
the discharge
is 4,000
feet downstream from the WWTP,
which
is 1,000 feet from the Mississippi River below the channel
dam.
Twenty percent
of the time high wat
prevents discharge
below the channel dam at outfall
001
(R.
74).
Discharge
is then
above
the channel dam at the unpermitted outfall
(See Pet. Exhs,
13,
17).
Besides
the
WWTP
discharge,
the City has six permitted
discharges
from seven combined sewer areas
(see Pet. Exhs.
1,2).
There are
three CSO outlets
La the existing pool of Lock
and Dam No,
26
(Id.
*007,
006,
005) while two CSO’s
(Piasa,
State)
join
at outlet *004
in the tailwater of the existing locks
and dam,
“The existing facilities allow overflow of untreated dry
weather and storm flows during periods when the river stage below
the existing dam
(tailwater)
is
415.3 mean sea level or higher.
A sluice gate
in the interceptor sewer must be
closed when flood
stages of the river exceed elevation
415,3
to prevent flooding of
the interceptor system with river water.,,,
Improvements
resulting from the Corps of Engineers work
to relocate Lock and
Dam 26 will result
in decreased frequency of such overflows,”
(Pet,
3).
The average amount of CSO’s discharged at outfalls
007,
006,
and
005
is estimated to be 1,1 million gallons per year
84-106
3
(Id.).
The estimated annual overflow from the Piasa—State CSO
diitlet
is 290 million gallons
per
year
(Id.
4).
The two
remaining CSO’s
(003,
002) discharge to an area known as the
Impoundment Area.
During normal river stages discharge is by
gravity to the Mississippi Rivet, but at high
rivet
stages
the
discharge
is pumped into the river.
The estimated annual
overflow from these two outlets is 282 million gallons per year
(Id.
5).
Before discussing the proposal and the two full compliance
options,
the relocation of Locks and
Dam
No.
26 and its effect on
this proceeding wii. be discussed.
The relocation will be
performed by the U.S.
Army
Corps of Engineers
(Corps).
A new
lock and
dam
structure will be located two miles downstream from
the present structure.
The relocation will change the area
covered by Pool 26.
The present pool has a normal elevation of
419 feet and a minimal elevation of 414 feet above mean sea
level.
(See Pet. Exh.
2).
The tentative schedule for
ucompletionu of the lock and dam relocation, meaning the date at
which the new pool will be raised,
is September 1987
(R.
98;
E.R.
32).
Three CSO’s discharge to the present pool and will be
unaffected by the dam relocation:
Turner (007), Bluff (006), and
Summit (005)
(Pet.
Rxh.
2).
The remaining CSO’s will be
affected.
Outfall 004, comprised of the State and Piasa CSO’s
will be greatly impacted.
This outfall discharges below the
present dam into the tail waters.
Upon dam relocation, the new
Pool No. 26 would inundate the Piasa CSO because of the CSO’s low
control elevation
(415.3 feet).
The Corps’ modifications to
lessen this impact to the Piasa CSO will consist of construction
of an eight by eleven foot new outlet sewer, relocation of the
Piasa and the State Street intercepting structures,
the
construction of a separate outlet
for the State Street sewer and
other miscellaneous construction
(Pet.
Exh.
6, R,38—9).
These
improvements will be paid for by the federal government
(R.91)
and will reduce sanitary sewer overflow BOD by 69 percent (R36—
40).
The new pool at elevation 419 will affect the impoundment
area which is at elevation 403. The Central and Shields CSO’s
discharge to this area.
A proposed Corps improvement is to
relocate the pumping station to the vicinity of the twin 60
pumps.
The combination of pumps in one area will combat the
increased water seepage from the relief wells of the levee
(R.89).
As outfall 001
is below the new lock and dam,
it will
be unaffected.
Although there are many different ways to juggle the
different control strategies to address the City’s three major
problems, there are basically three options for the Board to
focus on.
Two
are full compliance options.
The first
is a CSO
and
WWTP
upgrade and the second is a CSO upgrade with an
extension of the
WWTP
outfall pipe
(001) to the Mississippi
River.
The third option is the proposal favored by the City,
which includes limited CSO improvements.
64-107
4
The existing system is described more fully in the petition
(Pet.
ExIt.
14) while the City proposal is described
in
Petitioner’s Exhibit 8.
The limited CSO improvements include
construction of an interceptor sewer parallel to the southside
interceptor, modification of the Shields Valley regulator
chamber,
installation of a twelve inch interceptor between the
Shields Valley and the Shields Valley/Upper Altan intercepting
structures,
installation of an eighteen inch force main from the
southside pumping station to the WWTP, and increasing the peak
pumping capacity of the southside pump station from 8.9 MGD to
13.7 MGD (Pet. Exh.
8,
R. 42—3).
With these improvements,
combined sewer overflows would be reduced by 9.1 percent
(EcIS at
3—11).
The proposed improvements will cost the City $885,600
(Pet.
ExIt.
9, EcIS at 5—3, ER at 12;
ExIt. D to EcIS) and would reduce
the annual BOD discharge from the City by approximately 13
percent
(Pet.
Exh.
9).
The EcIS calculates this to be a nine
percent reduction, probably not including alternates B—l and 5—2
(EcIS, 3—11), which will be performed by the Corps
(see above;
references to alternates B—l,2,3 and 4 on Pet. Exh. 10 are no
longer valid; R.44).
The EcIS calculates that the proposal will
reduce TSS discharges from the existing system by nine percent (EcIS,
3—11).
Ammonia nitrogen would be reduced by 13 percent (jj.).
The two full compliance options both include alternate
4—A, which provides for a 36 inch force main and increase in pump
capacity, additional screening and grit removal, clarification,
chlorination, and dewatering equipment
(Pet. Exh.
16, ch.
10;
Pet. Exh.
7), for storage and treatment of first flush and
primary treatment of ten times the
dry
weather flow above the
first flush volume (see EcIS 3—8).
The CSO’s
BOD
and TSS
discharges would be reduced by 98 percent
(EcIS 3—8,—9, —10).
The first full compliancu option will be designated Plan
A.
It consists of alternate
4—A plus an upgrade of the WWTP,
including nitrification aeration, diversion and clarifier
facilities, return sludge pumping station,
blowers, tertiary
filters and filter pumping station tEdS 5—3~ The cost for plan
A would be the sun of costs for the CSO ($45,271,200) and
WWTP
upgrading ($9,898,800) provisions, totalling S55,000,000 (Id.).
In addition to the pollutant reductions from 4—A concerning CSO
discharges, WWTP BOD would be reduced by 80 percent, TSS by 93.1
percent, and ammonia nitrogen by 57 percent (EcIS 3—22).
The second full compliance option will be designated Plan
B.
It provides for CSO upgrade under alternate 4—A plus
extension of the sewer outEall to the MississippI River.
The
total cost would be the
sum
of the costs for the CSO improvements
plus that of the sewer outfall extension,
(315,000) or $45.6
million (BcIS 53).
The 4—A CSO reductions are also present as
in Plan h.
Because of the extension of the
WWTP
outfall to the
Mississippi, the upgrade p~ovisjonso~Plan A are avoided.
Under
Plan B, t~epercent reductiens trom the WWTP are 66 percent BOD,
93.1 percent TSS, and six percent ammonia nitrogen (EcIS 3—22).
64-108
5
The
C~.ty
asserts
an
arbitrary
or unreasonable
hardship
would
he
imposed
if
it
had
to
comply
with
the
regulations
(Petition,
Exh.
:14,
p.
13).
The two full compliance options,
Plan A and B,
would
cost
the City 55.2 million and
45.6
million dollars,
respectively, while the City’s proposal would
cost $885,000
(ER
11,12).
The annual costs under
the full compliance options would
be 3.7 million and 2.8 million dollars while
for the proposal,
the annual costs would be
$128,400 (Id.).
If the full compliance
annual costs are spread over the entire ~lton service area,
the
residential
annual
sewer
service
charge
could
increase
between
$91
t.o
$121
while
the
nonresidential
charge
would
increase
between
$505
to
$680
(EcIS
5—l0~
~11)~
Such charges
would
increase
by
two
to
299 percent
for residences
of
Godfrey
and
Bethalto
depending
upon
which
assumptions
are
used
(Id.
).
As
for
the
environmental
impact
of
the City~s
discharges,
the
City
testified
that
the
situation
is similar
to
two
others
studied
by the
Illinois
State
Water
Survey.
One
studied
the
effect
of
Altons
water
treatment
plant
discnarqe on the
Miss iss
ippi
the
other
analyzed
the
impact
of
Peoria
s
CSO ‘s
on
the
Illinois
River
(R48--9..
70—1).
rrom
the
studies
the
City
alleges
that
there
~s
no evidence
of
sludge
build—up
at
the
overflow
point
and
no
localized
effects
from
the
CSO’s
(R70—l).
Regarding
the
ammonia
nitrogen
concentration
of
the
WWTP
discharge
in relation
to aquatic
populations,
it
as known that
the average discharge concentration
is approximately 2.45 mg/I
while
the range
is 0.05
to
7
or
8 ppm (R78).
The City reports
that fish and other aquatic
life can migrate
over
the dam to go
upstream
in the Creek only
25 percent
of the year, which
corresponds to the high water elevations of
the Mississippi
(R.
80~see photo
in
Pet.,
Exh,
17),
V~vidence which
addresses
WQS
data
for
the
Creek
is
found
in
the
EcIS
at
pages
4-~4,
4—5.
Consistent
copper
and
iron
WQS
violations
have
occurred
in
addition
to
one
slJ.ver
WQS
violat:Lon.
Agency
sampl:ing
data
upstream
of
the
Creek
discharges
shows
a
mean
disso~.ved
oxygen
(DO)
concentration
of
8
mg/I
with
a
range
o.f
4.3
to
12J~
mg/i.
The
DO
WOS
was
violated
once
in
1982.
The
mean
ph
~
7.8
with
a
range
of
7.~) to
9~9
units.
The
highest
ammonia
nitrogen
concentration
dun ng the
1981—1982
period
was
0.74
mg/i while the average was less
tr~an half
of
that
figure
~EcIS
6—7~
Agency
sampling
data
for
the
years
l980~~i982were
obtained
for the Mississippi
River
at
its
sampLing
station
immediately
below Locks and Dam 26, approximately 300
feet
from
the
Clark
Bridge (EcIS
4~-17). This stataon
is
uostream
of
the Creek and
it
is not clear whether
it
is upstream or downstream of outfall
004
(Pet, Exh.
1).
The data shows consistent WQS ‘~‘iolationsfor
i.L~Ofl,
copper,
and
tecal
coliform,
Gthe:
Wç)S
violal:ions
included
two
for
lead
and
one
for
DO
in
1980
and
two
for
mercury
in
1981
(EcIS,
Table
4,2,
4—l3~ 4—17),
64..109
6
The Agency comments addressed two main concerns.
First, the
Agency states that the evidence
in the record is insufficient to
substantiate economic hardship for
dry
weather overflows as
requested in proposed rule I.
Overload of an interceptor due to
river backflow into the regulatory chambers should not happen if
design criteria are met.
The design criteria for such facilities
“requires
flood
protectton to maintain operational capability up
to a 25—year event and protection of facilities from damage
against a 100—year event.”
(Ag. Comments 1).
The evidence shows
that river backf
low
occurs at least eleven days annually.
The
Agency further stated that the discharge of untreated sanitary
sewage into waters of the State would violate Section 301(b)
(1)
(B) of the Clean Water Act
(33 U.S.C. 1311
(b)
(1)
(B)).
The
Agency would like the proposal modified to include adherence to
the design criteria for such facilities and to include
alternative A—2 in the rule.
The evidence of
lbS
vtolations in the Mississippi River for
the fecal coliform criterion dictates that any relief given
should not aggravate this situation.
Therefore1
the Board agrees
with the Agency’s amendatory language to “require the protection
and maintenance of the interceptor system from Mississippi River
backflow intrusion for the 25—year flood event” and to require
that alternative A—2 be implemented (Ag. Comments 1,2).
The second area addressed was that the City’s NPDES permit
does not include the alternate discharge point which is 4,000
feet upstream of permitted outfall 001.
Furthermore, the
potential costs of modifying outfall 001 to handle all
WWTP
discharges were not discussed in the record.
The Agency suggests
that requested relief should only be for permitted outfall 001
and that this should be stated tn the rule.
The Board notes that
this potential problem was raised at the economic hearing yet the
City has not suggested a solution.
The record is also silent as
to potential water quality violations for the 4,000 feet of Wood
River Creek below the alternative discharge point.
Therefore,
the Board will modify the proposed language to reflect the
outfall distinction.
As for ammonia nitrogen relief, the Board notes that such
relief has not been spectfically requested
in the proposal or
record.
Even had such relief been specifically requested in the
proposal, there Ls inadequate data to show that the ammonia
nitrogen
110$ will not be violated in the Creek, especially
in the
4,000 feet between the
WWTP
and outfall 001.
Agency data was
from sampling 1.6 miles upstream of outfall 001 and did not
include this 4000 foot segment between the
WWTP
and outfall 001
(EcIS 4—4a).
Therefore,
the environmental impact of any ammonia
nitrogen relief is uncertain and the aoard hereby declines to
address such relief in the Order.
64.110
7
In
adopting
the
amended
proposal
the amounts of BOD and TSS
that should
be removed for full
compliance will most likely end
up
downstream
from
Alton,
However,
the
Board
finds
that
the
full
compliance options
are economically unreasonable although
technically
feasible0
The Board further finds
that the amended
proposal
is technically feasible and economically reasonable
pursuant
to Section
27 of the Environmental Protection Act.
The Board will grant relief from
the
oft~ensive
discharge
regulation
of Section
304.106,
The
Board
finds
that
Alton
has
justified
the
need for relief
from the Board~s combined sewer overfLow regulations.
However,
the
Board
agrees
with
the
Agency
both
that the operational
capability
of
the
regulating
chambers of the interceptor system
should he protected against Mississippi River backflow intrusion
for the
25
year flood event and that there shouLd be maximum
utilization
of
the
south
side
interceptor
system~
including
upgrading
of
the
interceptor
pump
station.
The
Board
is
specifically concerned about
the
need
to
avoid
or
significantly
reduce the necessity
to discharge flows during
dry
weather
because of
system overload and malfunction caused
by river
backflows,
Therefore,
the Board will include the Agencyts
operational and design recommendations
as
part
of the rule.
This
will serve
to assure proper utilization of the interceptor system
and
at. the same time provide
the economic relief justified by
Alton.
The Board notes
that the City did not comment
on the Agency
recommendation,
and therefore, presumes that the City finds
the
recommendation acceptable.
In addition,
the
environmental
impact
data
provided
by
the
City
is
barely
adequate
to
support
the
relief
granted.
The
Board
realizes
that
the
proposed
rule
at
first
notice
is
somewhat
different
than
envisioned
by
the
City.
Comments
on
the
proposed
rule
may
he
submitted
during
first
notice,
The
following
language
as
set
out
in
the
Order
will,
be
incorporated into
35
iii.
Adm.
Code
304~2ic~
The
City
of
Alton
will be required to comply with
the
new section upon the filing
of the rule with
the
Secretary
of
State.
ORDER
Section 304.210
Alton
CSO and
Wastewater Treatment Plant
Discharges
This
Section
applies
to
the combined sewer
overflows
and
the
existing
wastewater
treatment
plant
3f
i~tori,
LLlinois,
a)
The
discharge
from
the
Piasa—State
Street
Sewer, defined
~
being
at Mississippi River
mile
202064,
shall
not
be
subject
t:athe
provisions
of
Sections
304.106,
304.120,
304,121
and
304.124
during
the
following
conditions:
64-111
8
I)
Prior to replacement
of the ~xi.stin~ Locks and Dam
26,
when
the
taiiwater
elevation
exceeds
415.3,
or
2)
After replacement of Lock and Dam
26,
when
the
pool
level
at the Piasa—State Street Outlet exceeds
the
~
202 64,
b)
DischaT. ..s from the City of
Alton
~t
Mississippi
River
miles
.66~Shie1dsVal1ey’)~202.2T
(Central
Avenue),
202,64
~iasa—State
Street),
203,4i
(Summit
Street),
203,87
fluff
Str~)
and
204.30
(!‘.:rner
Tract),
shall
be
subj•
~
to
the
fo11owin~j~r~,s~
1)
The
overflow
structures
and
the
associated
interceptor
sewer
shall
he
protected
against
intrusion
by
flood
waters
and
be
maintained
o~perational
at
flood
stages from Mississippi River
b~~.owfo~25-y~ar
Mississi~.
River
flood
2)
The City of Alton
shall
achieve
and
maintain
maximum
transport
capability
of
the
south
side
interceptor
sewer
system;
and
3)
The south side
interceptor pump station
shall be
upgraded to
a design capacity of
13.7 MGD,
c)
The discharge from the City of Altonts sewage treatment
works
outfa:Li.
001 sewer located
on
Wood River Creek,,
~pproximateij~OOO
feet
from
its
confluence
with
the
Mississipoi.
River,
shall
not
be
subject
to
35
Ill.
Adm.
Code
304,120(c)
out
shall
be subject to the following:
shall
not exceed
20 milligrams per
liter BOD and
25
milligrams
per
liter suspended solids.
Compliance
shall
be
determined consistent with
35
ill,
Adm,
Code
304,120(e)
35
111,
Mm,
Code
304,2~.0
is
~Li,rected
to
First
Notice,
iT
IS
SO
ORDERED.
I,
Dorothy
M.
Gunn,~ C1~k
of
the
:liinois
Pollution
Control
Board,
hereby
certify
that
the
above
Opinion~and
Order
was
adopted on the
________
____
day
of
~
,
1985
byavoteot
&‘d
.
~i?~
Doroth’~ M.. ‘Gunn,
Clerk
Il.in~~~:
Pollution Control Boar~
f~4-112
