ILLINOIS
POLLUTIOtSI CONTROL BOARD
January
21,
1988
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 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
mg/i fecal coliform 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 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 Alton,
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
Aiton 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
at
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
submitted
to supplement
the record.
85—289
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 USEPA preliminary comment
dated April
16,
1986.
In
that preliminary comment,
the USEPA
suggested the City might be able to
receive an exemption from the
requirement that all river
flows
up to
the
25 year flood event be
transported
to the wastewater treatment plant
if
additional
economic data were placed
in the record.
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
(‘Agency’),
and the USEPA 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,
arid
USEPA.
On June
22,
1987,
the Agency filed comments (docketed as
P.C.
#4)
in which were included comments of the USEPA.
In
response
to the Agency’s and
(JSEPA’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 has elapsed since
the Board’s initial
First Notice.
Section
5.01(d)
of the Illinois Administrative
Procedure Act requires that the Board again adopt
a proposal for
First Notice before proceeding
further with this rulemaking.
Consequently,
the Board will adopt
for First Notice
a version of
the proposal which
has been modified
in accordance with the
comments recently filed by the City and the Agency.
85-290
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 will be
performed by the U.S. Army Corps
of Engineers
(Corps).
A new
lock and dam structure
is located two miles downstream from the
present structure.
The relocation will change the area covered
by Pool
26.
The present pooi 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
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 biochemical oxygen demand
(BOD)
by 69 percent
(R.
36—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
85—29 1
Before discussing
the
recent filings by the City and the
Agency,
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 ~1WTPwas 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 more
strict standards for BUD and TSS.
The City requests relief from
the 10/12 mg/i 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/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 inundates 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 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
85—292
(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
arid
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—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
(Id.).
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 BUD and TSS
discharges would
be reduced by 98 percent (EcIS
3—8,—9,—lO).
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
85—293
($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.
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 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
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
CR78).
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).
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
85—294
shows
a mean dissolved oxygen
(DO)
concentration of
8 mg/l with
a
range
of 4.3
to 12.1 mg/i.
The DO WOS 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)
(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 indicate 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 ~WTP
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
85—295
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 proposal
the amounts of BUD 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 proposal
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
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 First Notice Comments,
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 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 indicates Agency agreement with
such
a view.
85—296
Recent Filings
Attached to its comments of June 22,
1987 the Agency
provides copies of correspondence from the USEPA 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 BUD5 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
BUD and suspended solids limitations.”
(P.C.
#4 attachment).
In response,
the Agency states that it disagrees with
USEPA’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
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
85—297
S
U
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
.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
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:
85—298
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.
Adm.
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 BUD5 and SS effluent
limitations for the WWTP be placed under
35
Ill. Adm. Code 304
rather than Part 306.
The Board agrees.
Also,
the Agency
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 proposal that the Board
is adopting for First Notice
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 propose the language as suggested by the Agency in its
comments.
ORDER
The Board hereby proposes
to adopt the following rule to be
published for First Notice
in
the Illinois Register.
TITLE 35:
ENVIRONMENTAL PROTECTION
SUBTITLE C:
WATER POLLUTION
CHAPTER I:
POLLUTION CONTROL BOARD
85—299
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 not exceed the following limitations:
20
milligrams per
liter for five day biochemical oxygeçi demand
(BUD5) (STORET number 00310)
and
25 milligrams per liter ~or 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 EXCEPTIONS
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
to the provisions of Sections 304.106,
304.120,
304.121 and
304.124 during the following conditions:
1)
Prior
to replacement of the existing Locks and Dam 26,
when the tailwater elevation exceeds 415.3;
or
2)
After
replacement
of Locks and Dam 26, where the pool
level exceeds elevation 420 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:
85—300
Protection Level
Mean 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 achieve and maintain maximum
transport capability of the south side interceptor sewer
system; and
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 achieve and maintain maximum
transport capability
of the South side interceptor sewer
system;
and
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
P
posed Opinion and Order
was adopted on the
~/t~4’
day of
________________,
1988,
by a
vote of
7—i
Dorothy M./Gunn, C~lerk
Illinois Pollution Control Board
85—301
