ILLINOIS POLLUTION CONTROL BOARD
May
19,
1988
IN THE MATTER OF:
R82—7
PETITION FOR SITE—SPECIFIC RELIEF
BY THE CITY OF ALTON
ADOPTED RULE.
FINAL ORDER.
OPINION AND ORDER OF THE BOARD
(by J.
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 Iii.
Adm. Code 304.106
(offensive
discharges),
304.120(c)
(10/12 mg/i BOD/TSS
effluent standards),
304.121
(400
fecal coliform per 100 ml bacteria effluent
standard),
304.124
(15 mg/i
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 sanitarf sewer overflows),
306.305
(treatment
of overflows and bypasses)
and 306.306
(compliance dates).
Procedural History
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
Altori,
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.
On May 16,
1985,
the Board adopted
a proposed rule for First
Notice.
The proposed rule was published
in the Illinois Register
(9 Ill.
Reg.
8392)
on June
7,
1985, which commenced
the 45—day
comment period.
The proponent,
City
of Alton
(City),
requested
by letter
an extension for
it to submit
its comments and did
submit them on August 22,
1985.
On October
29,
1985,
the Agency
filed
a letter which stated:
After receipt of Petitioner’s response to the
First
Notice,
the
Agency personnel
involved
had
a meeting with the City’s engineers
in an
effort
to
devise
an
alternate
solution
that
might
be
acceptable
to
all
parties
and
consistent
with
USEPA
regulations.
Discussions
are
continuing
and
at
the
earliest
opportunity
information
will
be
89—349
2
submitted
to supplement the record.
However, the negotiations ended without result and
the Board
received no more
information.
The Board adopted
a proposed rule for Second Notice on
March 27,
1986.
The
rule,
at Second Notice,
was modified
in
response
to First Notice comments and the apparent position of
the Illinois Environmental Protection Agency
(Agency)
as
evidenced by
a permit
it
issued
to the City.
Subsequent
to the Board’s Second Notice Order,
the Agency
filed letters with the Board dated April
9 and
17, 1986 stating
that this matter was still
in the negotiation process with the
City and United States Environmental Protection Agency
(USEPA).
Appended
to the April
17 letter was
a
tJSEPA preliminary comment
dated April
16,
1986.
In that preliminary comment,
the USEPA
suggested
that
if additional economic date were placed
in the
record the City might
be able
to receive an exemption from the
requirement
that all wastewater
be
transported
to the wastewater
treatment plant even up to
a
25 year
flood event.
The City then
moved
to authorize
an additional
engineering cost and feasibility
study.
The Joint Committee
on Administrative Rules
(JCAR)
issued
a certification of
no objection
to the rulemaking on April
17,
1986.
The JCAR certification was conditioned upon the Board
adding the clause
“nb
later
than the date
of completion
of Lock
and Dam No.
26”
to proposed Section 304.2l0(b)(3).
(That
provision is now Section 304.502(b)(3)).
On May
22,
1986,
the Agency filed
a request
that the Board
delay final
action until
the results
of the negotiations were
incorporated
into the record.
In its Order of May 22,
1986,
the
Board stated that
it would “await further comments from the City
City
of Alton),
the Illinois Environmental Protection Agency
(‘~gency’), and the (JSEPA before proceeding with this
rulemaking.”
The Board believed
that this was the “most
efficient course of action” given
the ongoing negotiation process
between the City, Agency,
and tJSEPA.
On June 22,
1987,
the Agency filed comments
(docketed
as
P.C.
#4)
in which were included comments of the tJSEPA.
In
response
to the Agency’s and USEPA’s comments,
the City filed
its
own comments with
the Board
on July 27,
1987
(docketed as P.C.
#5).
The Agency filed comments
(docketed as P.C.
#6)
in response
to the City’s comments
on August
19.
More than one year elapsed since
the Board’s
initial First
Notice.
Section 5.01(d)
of the Illinois Administrative Procedure
Act required that the Board again adopt
a proposal
for First
Notice before proceeding
further with this rulemaking.
Consequently, on January 21,
1988,
the Board adopted
for First
Notice
a version of
the proposal which had been modified
in
accordance with the comments recently filed
by the City and the
89—350
3
Agency.
That proposal was published in the Illinois Register on
February 16,
1988.
12
Ill.
Reg.
3547.
The Board received no
public comments during this First Notice period.
On April
7,
1988,
the Board proposed the same rule for
Second Notice.
The Joint Committee on Administrative
Rules
(JCAR)
issued
its Certificate
of No Objection on May 10,
1988.
At
the request of JCAR,
the Board has made some changes
to the
version of the
rule as
it
is adopting today.
Specifically, JCAR
asked
the Board to change Sections 306.502(b)(2)
and
(c)(l).
However,
it
is the Board’s position that
these changes do not
alter
the rule
in any substantive way.
Before discussing
the filings by the City and the Agency,
which prompted the Board’s second First Notice,
the Board will
recite the factual background
of this matter.
Background Information
The City
is faced with three problem areas:
receiving
stream reclassification, CSO elimination
(dry and wet weather
flows) and wastewater treatment plant
(WWTP) upgrade.
Prior
to
1982,
the receiving stream
for the WWTP was considered
to be the
Mississippi River
(River)
even though
it discharged into Wood
River Creek
(Creek)
approximately 1,000
feet from the
Mississippi.
The receiving stream is now classified
by the
Agency as the Creek, a low flow stream,
thereby imposing stricter
standards for BOD and TSS.
The City requests relief from the
10/12 mg/l BOD/TSS and
15 mg/I TSS effluent standards
(the 15
mg/l
standard is for
the CSO discharges while the 10/12 standard
applies
to discharges from the WWTP).
The City proposes
to meet
the prior
20/25 mg/l standards
for BOD/TSS
for its
WWTP
discharge.
Besides reclassification difficulties,
the City has
a CSO
problem.
There are prohibited overflows from sanitary sewers
to
the 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 River
iriundates certain CSO
areas
when the river
pool
level
is above elevation 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 River
proper.
The City’s
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,
an average design flow of 10.5 million gallons per day
(MGD),
and a peak design flow
of 26.25 MGD.
The service area
includes Alton,
part
of Godfrey Township,
and Bethalto.
Discharge
is
to either permitted outfall
001 or
to an unpermitted
89—351
4
outfall
into the Creek
near
the WWTP 5,000 feet from the River
depending on the elevation of the 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 River
below the channel dam.
Twenty percent of
the time high water
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
to 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
(Id.).
The estimated annual overflow
from the Piasa—State CSO outlet
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 River,
but at high River 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 will be discussed.
The relocation
is being
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 record indicates that the
“completion”
of the lock and dam relocation, meaning the date at
which
the new pool will be raised,
was scheduled for 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.
Exh.
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
39—352
5
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 flow biochemical oxygen demand
(BOD)
by
69 percent
CR.
36—40).
The new pooi 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 will be 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.
The existing system is described more fully
in the petition
(Pet.
Exh.
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 Alton 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.
Exh.
9, EcIS at 5—3,
ER at 12; Exh. 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 B—2
(EcIS,
3—11), which will
be performed by the Corps
(see
above;
references
to alternates B—1,2,3
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
(Id.).
The two full compliance options
both include alternate 4—A,
89—353
6
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,—l0).
The first full compliance 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
(EcIS
5—3).
The cost for plan
A would
be the sum of costs
for the CSO improvements
($45,271,200)
and WWTP upgrading
($9,898,800)
provisions,
totalling $55,000,000
(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 outfall
to the 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
(EcIS
5—3).
The 4-A CSO reductions are also
present as
in Plan A.
Because of
the extension
of the
WWTP
outfall
to the Mississippi,
the upgrade provisions
of Plan A are avoided.
Under Plan
B,
the
percent
reductions from the WWTP are
66 percent BOD,
93.1 percent
TSS,
and six percent ammonia nitrogen
(EcIS 3—22).
The City asserts an arbitrary or unreasonable hardship would
be imposed
if
it had
to comply with
the regulations
(Petition,
Exh.
14,
p.
l3).l
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
arid
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
eritT~e
Alton service area,
the
residential annual sewer service charge could increase between
$91 to $121 while the nonresidential charge would increase
between $505 and $680
(EcIS
5—10,
—11).
Such
charges would
1 The Board notes that the “arbitrary or unreasonable hardship”
standard
is that which
is applied
in
a variance proceeding.
In a
site—specific rulemaking,
a petition must demonstrate that
it
is
technically infeasible or economically unreasonable
to comply
with the general
rule.
The Board has applied the site—specific
rulemaking standard
in this proceeding.
89—354
7
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 Alton’s water treatment plant discharge on the
Mississippi,
the other analyzed the impact of Peoria’s CSO’s on
the Illinois River
(R48—9,
70—1).
From the studies the City
alleges that there
is
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 is known that
the average discharge concentration
is approximately 2.45 mg/l
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
(P.
80; see photo
in Pet.
Exh.
17).
Evidence 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 silver WQS
violation.
Agency sampling data upstream of the Creek discharges
shows
a mean dissolved oxygen
(DO)
concentration of
8 mg/l with
a
range of 4.3
to 12.1 mg/l.
The DO WQS was violated once in
1982.
The mean pH was 7.8 with
a range
of 7.0
to 8.9 units.
The
highest ammonia nitrogen concentration during the 1981—1982
period was 0.74 mg/l while
the average was less than half of that
figure
(EcIS
4—7).
Agency sampling data for the years 1980—1982 were obtained
for the River
at
its sampling station immediately below Locks and
Dam 26, approximately 300 feet from the Clark Bridge
(EcIS 4—
17).
This station
is upstream 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
violations
for
iron, copper,
and fecal coliform.
Other WQS violations included two for lead
and one for DO in
1980 and two for mercury in
1981
(EcIS, Table
4.2,
4—13,
4—17).
The Agency comments addressed
two main
concerns.
First,
the
Agency stated 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 protection
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 backflow 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)
89—355
8
(B)
of the Clean Water Act
33
U.S.C.
1311
(b)
(1)
(B)).
In
its
First Notice comments,
the Agency requested that the proposal be
modified to
include adherence to the design criteria for such
facilities and to include alternative A—2 in the rule.
The
Agency’s amendatory language
to “require the protection and
maintenance of the interceptor system from River backflow
intrusion for the 25—year flood event” and to require that
alternative A—2 be implemented
(Ag. Comments 1,2).
Recent
filings indicated
that the Agency
is recommending different
levels for flood protection.
The evidence of WQS violations
in the River for the fecal
coliform criterion dictates
that any relief given should not
aggravate this situation.
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 outall 001.
Furthermore,
the
potential costs of modifying outfall 001
to handle all WWTP
discharges were not discussed
in the record.
The Agency
suggested
that the requested relief should only be for permitted
outfall 001 and that this should be stated
in 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 specifically requested
in the proposal
or
record.
Even had such relief been specifically requested in the
proposal, there
is inadequate data
to show that the ammonia
nitrogen WQS 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 Board hereby declines
to
address such relief
in the Order.
In adopting today’s rule 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 feasible.
The Board further
finds that the adopted
rule
is technically feasible and economically reasonable pursuant
to Section
27 of the Environmental Protection Act.
The Board will grant relief from the offensive discharge
regulation
of Section 304.106.
The Board finds that Alton has justified
the need for relief
89—356
9
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
be protected against backflow intrusion by the River 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.
In
its Comments,
submitted during the first First Notice
period,
the City stated that after
the relocation of Lock and Dam
26, discharges
from the Piasa—State Street sewer should not
be
subject
to certain effluent limitations when the mean sea level
of the River exceeds
420
feet at River
Miles 203.12 and 203.22.
In other words, at a level
less than the 25—year flood stage.
Similarly,
the City also contended that
it could only flood proof
certain combined sewer overflow structures up to specific River
levels which are below the 25—year flood
stage.
In its first
Second Notice Order,
the Board adopted
a version of the proposal
which accepted the protection elevations specified by the City.
Recent filings and past permitting action by
the Agency have
indicated that the Agency agrees with such
a view.
Recent Filings
Attached
to its comments of June
22,
1987 the Agency
provides copies of correspondence from the tJSEPA which evaluate
the City’s proposal.
First,
the USEPA,
in
a letter dated August
8,
1986, asserts that the City has not substantiated the need for
relief from the BOD5 and SS effluent limitations of 10/12.
The
City requests
that its WWTP discharges be subject
to a 20/25
standard.
The USEPA bases
its conclusion on the high quality of
WWTP effluent as exhibited by recent plant performance.
However,
the USEPA concurs with the Agency that “no significant water
quality influences are likely
to result from the relaxation of
BOD and suspended solids limitations.”
(P.C.
#4 attachment).
In response,
the Agency states that
it disagrees with
tJSEPA’s recommendation against
relief.
The Agency explains:
USEPA’s
position
is
based
on
“present plant
performance”,
which
ignores
the
fact
that
Alton’s
treatment
plant
was
constructed
to
receive
a
design
average
flow
of
10.5
MGD
(million
gallons
per
day)
and
currently
receives
flows
of
only
about
half
that
amount.
Flows
to the plant averaged
5.56 MGD
in
1984,
5.23
MGD
in
1985,
and
5.19
MGD
in
1986.
The reason
for
the difference between
design
flow
and
flows
actually
received
is
due
to
the
generally
depressed
economic
89—35 7
10
condition
of
the
Alton
area,
and
flows
tributary
to
the
treatment
plant
would
be
expected
to
increase
as
the
economic
condition
of
the
area
improves.
More
importantly,
USEPA’s
position
ignores
the
fact
that
the
Alton facility was built
as
a
federal grant funded project to meet effluent
limitations
of
20/25
and
not
10/12.
The
record
documents
that
20/25
is
adequate
to
protect water quality and
the proposed
20/25
limits
are
certainly
more
stringent
than
federal
secondary
treatment
requirements
(30/30).
(P.C.
#4,
p.
1—2)
Finally, with regard
to this issue,
the Agency believes that
the “anti—backsliding” provisions of Section 404 of the re—
authorized Clean Water Act would not apply.
The next issue addressed by the Agency
in
its comments
concerns improvements
of the sewer
system.
Specifically,
at
issue
is the cost of improvements
to the sewer system which would
enable
the transport
of sewage
to the WWTP during River flood
conditions
up to
and including the 25—year flood event.
The
Agency submitted
a letter
from Crawford,
Murphy
& Tilly,
Inc.
(CMT),
consulting engineers
for the City,
which details the cost
of such improvements.
CMT states
that
a 25—year
flood level corresponds to
a River
elevation
of 432.5
feet.
According to CMT, improvements on the
sewer system
to provide flood proofing
to such
a River level
would create expenditures totaling $6,250,000.
CMT states that
the City’s system
is currently protected
up to
a 2.5 year flood
event,
which corresponds
to
a River elevation of 415.3
feet.
CMT
asserts
that the City’s current annual debt service
for sewer and
wastewater treatment plant improvements equates
to $377,000.
According
to CMT,
if flood
protection up to the 25—year
flood
level
is instituted,
the annual debt service will increase to
$1,000,000.
CMT also states that the River’s flow above the 2.5
year flood event
is
in excess
of 250,000 cubic feet per second,
which is approximately 162 billion gallons per day.
Under such
circumstances,
the City’s discharge would be 0.86 million gallons
per day which,
according
to CMT, would amount to 0.0005
of
the
River’s total
flow.
(P.C.
#4 attachment).
The Agency has also submitted
a USEPA response
to CMT’s cost
estimate.
In a letter dated May 5,
1987,
the USEPA states:
Based
on our review,
we believe
that
a proper
economic
analysis
was
completed
(consistent
with
40
CFR
131),
and
due
to
the
circumstances
that
exist
at
Alton,
bypasses
due
to
high
river
stages
at
something
less
89—358
11
than
the
25—year
flood
event
can
be
authorized
under
40 CFR 122.4(m).
(P.C.
#4 attachment)
The Agency
is apparently now in agreement with the levels
of
protection requested by
the City (P.C.
#6).
In
its July
27,
1987 comments,
the City addressed
two
concerns.
First,
the City states that the protection elevation
for
the Summit Street overflow structure should
be listed at
426.7
feet not 427.0
feet
as
it was listed
in the Board’s Second
Notice Order
of March 27,
1986.
The second and more substantive
point
is that the City proposes language,
to be added
to the
rule, which expressly exempts the City from 35
Ill. Adm. Code
306.305(b).
(P.C.
#5).
The Agency filed
its response to the City’s comments on
August
19,
1987.
The Agency agrees with the City’s protected
elevation figure
for the Summit overflow structure.
In addition,
the Agency states that since
the Summit, Bluff, and Turner
structures
are all connected,
they should be protected to the
same elevation.
As
to the City’s request for express relief from
35
Ill. Adm. Code
306.305(b),
the Agency
responds:
The
issue
of combined
sewer
overflow
(“CSO”)
relief
must
be
addressed
in
the
context
of
the
site specific
rule
change.
The City has
not formally sought an exception from
35
Ill.
Mm.
Code
306.305(b).
However,
even
though
the
exception
procedure
has
not
been
utilized,
the Agency agrees
with
the Board’s
previous
statement
that
“...Alton
has
justified
the
need
for
relief
from
the
Board’s
combined
sewer
overflow
regulations.”
(Proposed
Opinion
and
Order,
May
16,
1985,
at
p.
7).
Actually,
wet
weather
relief
for
the
City
should
also
include
Section
306.305(a)
as
well.
This
portion
of the site specific relief should be
promulgated
under
Part
306,
Performance
Criteria.
Additionally,
the CSO’s
for
which
relief
is sought should
be designated by name
and
location
rather
than
as
“all
existing
combined sewer overflows.”
(P.C.
#6)
Finally,
the Agency suggests some non—substantive
alterations
to the proposed rule.
The Agency suggests that the
portion
of
the rule concerning
the BOD5 and SS
effluent
limitations
for the WWTP
be placed under
35
Ill. Mm. Code 304
rather
than Part 306.
The Board agrees.
Also,
the Agency
89—359
12
suggests that the rule expressly require that “the
south side
interceptor pump station shall be upgraded
to
a design capacity
of
a minimum of 13.7 million gallons per day.”
The previous
version
of the rule lacked the word minimum.
The Board also
agrees with this change.
In the rule that the Board
is adopting
today,
the Board has
altered the protection elevation of
the Summit overflow structure
in accordance with the City’s and the Agency’s comments.
As
to the requested language regarding an exemption from
Section 306.305, the Board concurs with the Agency’s position and
will adopt the language as suggested by the Agency
in its
comments.
ORDER
The Board hereby adopts the following amendments
to be filed
with the Secretary
of State:
TITLE
35:
ENVIRONMENTAL PROTECTION
SUBTITLE C:
WATER POLLUTION
CHAPTER I:
POLLUTION CONTROL BOARD
PART 304
EFFLUENT STANDARDS
SUBPART B:
SITE SPECIFIC RULES
AND
EXCEPTIONS NOT OF GENERAL APPLICABILITY
Section 304.210
Alton Wastewater Treatment Plant Discharges
The discharge from the City of Alton’s
(Alton) sewage treatment
works
outfall 001 sewer located on Wood River Creek,
approximately 1,000 feet from its confluence with
the Mississippi
River,
shall not be subject
to Section 304.120(c).
Instead,
Alton’s discharge shall
riot exceed the following limitations:
20
milligrams per liter
for
five day biochemical oxygen demand
(BOD5)(STORET number 00310)
and 25 milligrams per liter
for total
suspended solids
(STORET number
00530).
Compliance shall be
determined consistent with Section 304.120(e).
(Source:
Added at,
12 Ill. Reg.
effective
PART 306
PERFORMANCE CRITERIA
SUBPART
F:
SITE SPECIFIC RULES AND EXCEPTIO1~S
Section 306.502
Alton Combined Sewer Overflow Discharges
a)
The discharge from the Piasa—State Street Sewer,
defined as
being at Mississippi River mile 202.64,
shall not be subject
89—360
13
to the provisions of Sections 304.106, 304.120,
304.121 and
304.124 during the following conditions:
I)
Prior
to replacement
of
the existing Locks and Dam
26,
when the tailwater elevation exceeds 415.3 Mean Sea
Level
(MSL);
or
2)
After replacement of Locks and Dam 26, where the pool
level exceeds elevation
420 MSL at Mississippi River
miles
203.12
and 203.22
(Piasa and State Street Outlets
relocated).
b)
Discharges from the City of Alton at Mississippi River miles
201.66
(Shields Valley),
202.24
(Central Avenue),
203.12
(Piasa Outlet),
203.22
(State Street Outlet),
203.61
(Summit
Street),
203.87 (Bluff Street) and 204.30
(Turner Tract),
shall
be subject to the following conditions:
1)
The overflow structures and the associated interceptor
sewer shall
be protected against intrusion by flood
waters and
be maintained operational at flood stages
from Mississippi
River backflow for
a 25—year
Mississippi River
flood stage,
except as follows:
Prote
Mean
ction Level
Sea Level
(MSL)
Overflow Structure
River Mile
River Stage
Piasa Outlet
203.12
420.0 MSL
State Street Outlet
203.22
420.0 MSL
Summit Street
203.61
426.7 MSL
Bluff Street
203.87
426.7 MSL
Turner Tract
204.30
426.7 MSL
2)
The City of Alton shall maintain the south side
interceptor sewer system
in
such working condition so as
to ensure that the system will flow
at
a maximum
capacity.
3)
No later than the date
of completion of
Lock and Dam
26
the
south side interceptor pump station shall
be
upgraded
to
a design capacity of
a minimum of 13.7
million gallons
per day.
c)
Discharges from the combined sewer overflows designated
in
paragraph
(b) shall not be subject
to the treatment
requirements
of Section
306.305(a)
and
(b) provided that:
1)
The City
of Alton shall maintain the south side
interceptor sewer system
in
such working condition
so as
to ensure that the system will flow at
a maximum
capacity.
89—361
14
2)
The South side interceptor pump station shall
be
upgraded
to
a
design
capacity
of
a
minimum
of
13.7
million
gallons
per
day.
(Source:
Added
at
12
Ill.
Reg.
effective
)
IT
IS SO ORDERED.
I,
Dorothy
M.
Gunn,
Clerk
of
the
Illinois
Pollution
Control
Board,
hereby
certify
that
the
above
Proposed
Opinion
and
Order
was
adopted
on
the
/7~Z
day
of
________________,
1988,
by
a
vote
of
7-o
.
~
~.
Dorothy
M.~~unn,
Clerk
Illinois
I~6llution
Control
Board
89—362
