ILLINOIS POLLUTION CONTROL BOARD
April 21,
1988
IN THE MATTER OF:
THE PETITIO.~OF THE
)
R86—3
NORTH SHORE SANITARY DISTRICT
)
TO AMEND REGULATIONS
!ROPOSED RULE.
FIRST NOTICE
OPINION AND ORDER OF THE BOARD
(by B.
Forcade):
This matter comes before
the Board
on
a December
20,
1985,
Petition of the North Shore Sanitary District
(“NSSD”) for
a
site—specific regulation
to modify the Board’s effluent
phosphorus
regulations.
Specifically, the petition seeks
an
exception from 35
Iii. Adm.
Code 304.123(a)
for
the discharges
of
phosphorus
in excess
of
1 mg/i
in the effluent
from the excess
flow facilities
located at
the Waukegan Sewage Treatment Plant
(“STP”)
and the North Chicago STP.*
A public hearing
was held
October
19,
1987,
in Waukegan,
Illinois.
No member
of
the public
was
in attendance.
The Department
of Energy and Natural
Resources submitted
its negative declaration
re an Economic
Impact Study
(EcIS)
on this proposed site—specific
rule on
December
15,
1987.
Supplemental
information,
requested at
hearing, was filed with the Board
by the Illinois Environmental
Protection Agency (“Agency”)
on January 22,
1988,
and by NSSD on
January 27,
1988.
*By another,
independent petition, NSSD sought relief from the
Board’s Combined Sewer Overflow (“CSO”)
rules,
35
Ill.
14dm.
Code
306.302 through 306.306.
The February
5,
1987 Opinion and Order
in that proceeding,
PCB 85—208,
permits no CSO discharges
to the
lake until conveyance of the maximum flow to Gurnee and the North
Chicago retention basins are full.
It requires the construction
of
a
50 MG excess flow retention facility at Gurnee by January
1,
1991,
then does not permit discharges
to the lake until either
the Gurnee and North Chicago retention facilities are full
to
capacity,
or the plant inflow exceeds
the pumping capacity
to
Gurnee and the North Chicago retention
facility
is full
to
capacity.
The PCB 85—208 Opinion and Order permits CSO
discharges
from Waukegan only after “the maximum practical flow
is receiving
full treatment
and
the excess flow basins are
full
to capacity”
(February
5,
1987 Opinion
and Order
in PCB 85—208 at
pp.
8—9).
The Opinion and Order
in PCB 85—208 further
requires
NSSD
to monitor
the impact of its CSO discharges on the lake,
but
not specifically
for phosphorus.
88—409
—2--
The Board has determined
that the record does not indicate
that NSSD waukegan and North Chicago overflow discharges
demonstrably cause
or contribute
to phosphorus water quality
standard violations.
Conversely,
the Board
is troubled with the
prospect of
their undiminished continuation, whether
with
or
without chemical phosphorus
removal.
The Board has decided
to
adopt
a site—specific rule that would eliminate
the existing
effluent phosphorus limitation
for these discharges.
Chemical
phosphorus
removal
from the Waukegan STP and North Chicago STP
is
not clearly technically feasible and
is clearly not economically
reasonable.
Similar
or greater environmental benefits are
achievable
through alternative means.
Although NSSD has requested
a scaled numerical phosphorus
effluent limitation dependent on the number
of discharge events
occurring during
a given month,
this Board declines
to adopt this
approach.
The record more adequately supports adopting measures
intended to minimize overflow discharges.
This
includes adoption
of certain plant practices
and mandating
an expansion
in plant
peak treatment
and retention capacity.
This was the approach
favored by the Agency.
The Board further adopts the Agency’s
recommended monitoring scheme with only slight modification.
I.
Background
The NSSD was formed
in 1914
under the Sanitary District Act
of 1911
(Section 276.99,
et seq.,
chapter
42, Ill.Rev.Stat.).
The District encompasses
the area
in Lake County,
Illinois,
lying
east
of the tollway extending from the Lake—Cook County Line Road
north to
the Wisconsin border, except
for the Village
of
Deerfield, part
of the Village
of Bannockburn,
and the Wadsworth
area.
The eastern border
is the Lake Michigan shoreline.
The
NSSD services approximately 210,000 people
(R.
52; see PCB 85—
208,
February 25,
1987 Opinion and Order).
The NSSD operates four sewage treatment facilities,
only two
of which
are of primary concern
to this proceeding.
The sewage
treatment system has two CSO outfalls which discharge only
intermittently
to Lake Michigan..
Effluent phosphorus limitations
apply by regulation only
to discharges
to the lake.
These two
intermittent discharges are separately discussed below.
Discussions
of the potential
impact of the phosphorus discharges
on the lake and the NSSD—proposed alternative rule and
the Agency
proposal
follows those.
Waukegan STP
The Waukegan STP service area primarily includes separate
sanitary sewers.
The plant
is an activated sludge plant with
a
design capacity of 19.8 million gallons per day (“MGD”)
throughput,
and its average dry weather
flow receiving full
treatment was 14.1 MGD
in 1978—79.
The plant can provide full
treatment
to
a peak flow of about
30 MGD during wet weather and
its average wet weather flow was 26.0
NIGD during
this period.
88—4 10
—3—
This period saw an average combined flow of
18.0 MGD receiving
full treatment
(Ex.
4,
p.
3—1;
R.
61,
64
&
68).
The treated
effluent
is pumped about
five miles overland by force main from
the plant location on the shore of
Lake Michigan
to an outfall
to
the Des Plaines
River
(See
Ex.
18;
R.
54).
No phosphorus
limitation
applies
to this discharge.
The
treatment plant
is not capable of providing
full
treatment
to all flows during wet weather periods.
During
extreme wet weather conditions,
excess combined sewage—stormwater
influent first enters
a pair
of presedimentation basins having
a
combined capacity of
1.38 million gallons
(“MG”).
Overflows from
these basins successively enter three retention basins.
Additional
flows exceeding the
38 MG capacity of these
three
basins exit
the third basin,
are chlorinated
in
a contact
chamber,
and discharged
via
an overflow outfall
to Lake
Michigan.
This outfall is used only
intermittently during such
extreme wet weather plant overflow events.
This effluent
receives no treatment other
than any primary settling
it
undergoes
in the presedimentation and retention basins,
and the
chlorination described
(Cx.
4, pp.
3—1—3—2;
R.
58—60).
The
record does not indicate whether
it
is feasible
to pump
the
untreated overflow
to the Des Plaines
River with the treated
effluent.
No current facilities exist
for phosphorus
removal
from this overflow effluent
(Cx.
4,
p.
3—1).
No additional
land
is
immediately available
for expansion of the overflow storage
capacity at this plant
(R.
85).
The record testimony
indicates that
for part
or all of the
years 1979—83,
the Waukegan STP experienced
an average of
25 such
discharge events per year with an annual average discharge of
267.5 MG
to the lake
(Ex.
4,
p.
4—10).
This
is based on
a study
of the impact of the phosphorus
in the overflow discharges by a
consulting engineer contracted by NSSD,
Donald
F.
Pirrung
of
Donohue
& Associates,
Inc.
The record indicates that continuous
overflow may occur from
a few hours
to two days.
Such are called
“events”
by the witnesses
(R.
17—19, 43—44
& 115),
but certain
more detailed data
for
the years 1980—87 are tabulated by
discharge per day.
For clarity, the discharge per day
is
discussed
as “event—days”
in the following discussions
of these
1980—87 detailed data.
These are likely equivalent
terms.
Other, more detailed data spanning
a longer time than that
relied on by the NSSD engineer indicate
an annual average
discharge of
362.7 MG and
an average
of
30 events per year.
These more extensive data permit
a detailed analysis not possible
based on the NSSD engineer’s
study.
They are based on detailed
tabulations
of
224 overflow event—days during all
or part of the
years 1980—87.
Overflow discharge volume data were available
for
223 of
these event—days, effluent phosphorus data were available
for 197, and both
types of data were available
for 196
(Cx.
4,
pp.
4—8;
Cx.
5, App.;
Cx.
7).
88—411
—4—
This detailed tabulation
indicates
that overflow discharges
are sporadic, unpredictable,
and potentially massive.
For
example,
the lowest year saw only seven event—days with
a total
of 97.0
MG,
and
the highest year
saw 49 event—days with
a total
discharge
of 655 MG.
The highest
recorded
single event during
this period was the discharge of 67.7 MG.
During
a 25—day period
during March
and April,
1983,
an event—day occurred every day for
a
total overflow discharge of 315.8 MG to the
lake.
A similar
succession
of
24 event—days occurred during February and March,
1985, which discharged
a total volume of 398.1 MG
to
the
lake.
No precipitation data
in the record correlate with the overflow
data, but the general pattern
is for the event—days
to occur
on
each of
from one
to several days
in
a row
(5 days average)
——
presumably only during periods of extreme
rainfall runoff.
There
appears no definite pattern to either
the daily flow or the
phosphorus content of the discharges during these several day
periods.
A summary tabulation of the annual totals
and averages
follows:
Summary Tabulation:
Annual Waukegan STP Overflow Data
Annual
Annual
Phosphorus
Year
Discharge
Events
Average*
1979
356 MG
37
1.8 mg/l as
P
1980
213
19
1.38
1981
97
7
0.95
1982
354
34
1.17
1983
417
34
1.07
1984
191
21
1.09
1985
655
49
1.19
1986
638
43
1.09
1987
(6 mos)
l55**
17
1.16
Total
(8.5 yrs)
3,076 MG
261
——
Average
362 MG
31
1.22 mg/l
as P
*
Indicates average total phosphorus based on available data
only.
Some data were missing for each of nearly all years
**
Indicates total discharged volume
for available data.
One
datum was missing.
Examination of the detailed
1980—87 discharge data,
categorized by size of
the individual event—days,
illustrates
that elimination of smaller discharges diminishes
the number
of
discharges more rapidly
than it diminishes
the
total volume
discharged.
In the following
table,
the left column categorizes
event—days by their
individual discharge volume.
The next two
columns indicate the number and percent
of event—days discharging
the given volume.
The
fourth column indicates
a cumulative
percentage
of the numbers of event—days discharging the given
volume
or
less.
The right
three columns indicate the total
volume discharged
in each of
the given categories,
the percent
of
88—412
—5—
the total volume
that fell
within that category,
and the
cumulative
percentage
of
the
total
volume
that
falls
in
the given
and
smaller
categories.
The
table
follows:
Numbers
and
Volumes
of
Waukegan
Overflow
Discharges
by
Event
Size
By
Number
of
Events
By Category
Volume
Size
of
Event
Number
Percent
Cum
MG
Percent
Cum.
Less
than
1
MG
8
3.6
3.6
3.8
0.1
0.1
1 MG to
5 MG
58
26.0
29.6
164.9
6.1
6.2
5
MG
to
10
MG
59
26.5
56.1
445.4
16.4
22.6
10
MG
to
15
MG
34
15.2
71.3
422.2
15.5
38.1
15
MG
to
20
MG
28
12.6
83.9
497.0
18.3
56.4
20
MG
to
25
MG
14
6.3
90.1
311.5
11.5
67.8
25
MG
to
30
MG
5
2.2
92.4
135.2
5.0
72.8
30
MG
to
40
MG
5
2.2
94.6
168.7
6.2
79.0
40
MG
to
50
MG
8
3.6
98.2
345.1
12.8
91.8
Greater
50
MG
4
1.8
100.0
223.3
8.2
100.0
Totals
223
100.0
—
2,720.1
100.0
—
The
mean
event
size
indicated
by
this
data
was
12.2
MG.
The
median
was
about
9.0
MG,
but
more
than
half
the
overall
effluent
volume
consisted
of
events discharging more than 18.6 MG.
Elimination
of
the
first
10
MG
of
all
event—days
reduces
the
number
of
event—days
from
223
to
98
(from
30
to
13
per
year,
average)
and
the
overall discharge volume from 2,720.1 MG
to
1,126.0
MG
(from
363
MG
to
150
MG
per
year,
average;
58.6
reduction).
Elimination of
the first
14
MGD
of
all
event—days
reduces the number of event—days to 72
(10 per year,
average)
and
the overall discharge volume
to 792.4
MG (105.6 MG per year,
average;
70.9
reduction).
The NSSD engineer estimated,
based on
1979—83 data,
a reduction from an average of
37 events and 267.5
MG discharged per year
to an average of
4 events
and 19.8 MG
discharged per year
(93
reduction)
if certain proposed plant
improvements occurred at Waukegan.
These respective estimates
are disparate,
and they are significant to later discussion.
The NSSD engineer indicated that the annual average
phosphorus content
of the Waukegan discharges during 1979—1983
ranged from 0.95
to 1.8 mg/l,
with an overall
average over
the
nearly five years of 1.3 mg/l
(Ex.
4,
p.
4—10;
R.
17).
Examination of
the 197 detailed data for which phosphorus
is
available
for 1980—87 reveals the same range,
but an overall
average of 1.14 mg/l
as
P.
A summary tabulation of
the 197
detailed data, categorized by effluent phosphorus content and the
associated percentage
of discharges within each category,
follows:
88—4 13
—6—
Number of Event—Days Discharging Specified Phosphorus In Effluent
Effluent Phosphorus Content
(rr~/las P)
Year
1.0
1.0—1.5
1.5—2.0
2.0—2.5
2.5—3.0
Total
1980
0
0
11
61
7
39
0
0
0
0
18
1981
6
85
0
0
1
14
0
0
0
0
7
1982
9
31
16
55
4
14
0
0
0
0
29
1983
8
26
19
61
4
13
0
0
0
0
31
1984
7
35
12
60
1
5
0
0
0
0
20
1985
17
38
23
51
4
9
0
0
1
2
45
1986
13
38
13
38
6
18
1
3
1
3
34
1987
5
38
5
38
3
23
0
0
0
0
13
‘IOTAL
65
33
99
50
30
15
1
1
2
1
197
CUM.
65
33
164
83
194
98
195
99
197
100
During
this
entire
period,
only
80
(41)
of
the
samples
complied
with the effluent standard
of 1.0 mg/i
as
P applicable
to Lake
Michigan discharges.
The highest individual datum submitted was
2.7 mg/l
(Ex.
4,
p.
4—8;
Cx.
5 App.;
Ex.
7).
The record indicates that the amount
of total phosphorus
discharged by Waukegan
in excess of
the standard
is
a fraction
of
the total discharged
in the effluent.
The NSSD engineer
indicated that the average annual
total phosphorus loading
to
Lake Michigan during
the period
including part or all
of 1979—83
was 2,900 pounds
(Cx.
4,
p.
4—10)
——
only 668 pounds
(30
percent)
in excess
of what would have entered
the lake had the effluent
consistently averaged 1.0
mg/i total phosphorus
(as P).
Analysis
of the 196 tabulated individual
1980—87 event—days for which both
total phosphorus and flow data were available indicates
that
Waukegan discharged
a total
of 25,950 pounds of total phosphorus
to
the lake during this seven and one—half years,
for
an annual
average
of 3,460 pounds
as
P.
Factored up to account for the
12.5
of event—days
for which
the data
is incomplete, the total
becomes 29,660 pounds,
or an annual average of
3,950 pounds as
P.
Further analysis of these detailed data
indicates that the
Waukegan STP overflow discharges
in excess
of 1.0 mg/i total
phosphorus added an excess of
3,240 pounds of total phosphorus
to
the lake
in violation
of Section 304.123(a),
or
an average excess
of about 433 pounds per year,
when factored
to account
for the
12.5
of event—days
for which complete phosphorus and flow data
are missing.
Again,
an analysis based on the more recent data
conflicts slightly with
the NSSD engineer’s estimates.
Existing plans
to enlarge
the Waukegan plant were central
to
the NSSD engineer’s estimates on phosphorus
removal.
The current
201 Facilities Improvements plan for the Waukegan STP calls
for
an increase
in the design capacity of
the plant to 22.0
MGD.
This would
increase the peak treatment capacity to about 44
MGD.
The intent of this plan
is to accommodate anticipated
demand
for treatment capacity
in the existing NSSD service area
for
the year 2000.
It does not consider the possible addition
of
88—414
—7—
more
geographic
area
to
the
west
of
the
existing
boundaries.
NSSD
has
not
committed
to
making
these
improvements
(R.
66—67
&
73—75).
This additional
treatment capacity would
boost
the
current Waukegan plant peak treatment capacity of
30 MCD by about
14
MGD.
It was upon these expansions
that all phosphorus
discharge
reduction and removal cost estimates were based.
As
indicated earlier, NSSD anticipates
that these
improvements,
if implemented, would reduce the anticipated number
of overflow events per year from
37
to only four, with
a total
estimated annual average volume from 267.5 MG
to only
19.8 MG
(93
reduction)
(Ex 4,
p.
3—1;
R.
72—73).
As mentioned
earlier,
examination of
the detailed
1980—87
data
indicates
that
elimination of
the first
14 MG from all event—days
reduces
their
number per year
from 30
to
10 and the annual discharge volume
to
the lake from 362.7 MG
to 105.7 MG
(70.9
reduction)
for this
period.
The estimates possible, based
on 1980—87 data,
clearly
conflict with the NSSD estimates based on 1979—83 data.
This
warrants separate examination
of
the potential benefits.
Comparative estimation of the phosphorus reductions possible
by
the three options discussed
in the record (implementation
of
the 201 Plan,
chemical phosphorus removal,
and implementation of
the plan with chemical phosphorus
removal) reveals that
implementation
of the 201 Plan confers greater benefits than
chemical removal.
Chemical removal
in addition
to plant
improvements confers only
a slightly increased benefit
than flow
diversion alone.
This
is true of either the NSSD engineer’s
estimates based on 1979—83 data
or estimates based on the 1980—87
detailed data.
The 1980—87 data indicate that flow diversion,
above
estimated
at
70.9,
reduces
the annual total phosphorus
output from Waukegan from 3,950 pounds per year
to 1,150
pounds
per year
as
P.
This eliminates 2,800 pounds of total phosphorus
from discharge
to the lake.
Chemical phosphorus removal alone
would only eliminate
the 433 pounds of total phosphorus currently
entering the lake in excess
of
1.0 mg/i
in the effluent
(10.9
reduction).
This permits the discharge
of 3,520 pounds per year
as
P.
Chemical phosphorus removal along with the 201
improvements would eliminate only
126 pounds
of phosphorus
in
addition to the
2,800 pounds eliminated
by diversion alone,
allowing 1,030 pounds
to enter
the lake
(74.1
reduction).
For
comparative purposes,
these estimates are tabulated below
parallel
to those made by the NSSD engineer:
88—4 15
—8—
Comparison
of
NSSD
and
Estimated
Phosphorus
Reductions
by
Method
of
Reduction
for
Waukegan
Phosphorus
Discharges
Phosphorus
Reduction
Method
NSSD
1979—83 Estimates
1980—87 Estimates
Existing Facilities
2,900 pounds
3,950
pounds
Chemical Removal Alone
2,230
pounds
3,520
pounds
Phosphorus
Reduction
23
10.9
201
Facilities
Improvements
215
pounds
1,150
pounds
Phosphorus Reduction
93
70.9
Both
Methods
Together
165
pounds
1,030
pounds
Phosphorus
Reduction
94
74.1
The report of the consulting engineer retained by NSSD
to
study phosphorus
removal
from the Waukegan overflow effluent
to
Lake Michigan
indicates that
the capital costs
of installing
equipment
for chemical phosphorus
removal are about
$682,900,
whether
or not the 201 Facilities Plan
improvements are made.
The annual operating costs are estimated at $40,500
if
the
improvements are not made.
This reduces
to an estimated $21,100
per year
if
the plan
is implemented.
This reduction probably
results
from the decreased overflow volume
the improvements would
allow.
The annualized cost per pound of phosphorus
removed was
estimated
at $158 with existing plant facilities and $1,738
if
NSSD implements
the 201 Plan
(Ex.
4,
p.
5—3).
Testimony
indicates
that the normal cost per pound
of phosphorus
removed
from
a continuous effluent stream
is
in the range of
$1
to $3
(R.
117—118).
The stated reasons
for the greatly increased cost of
removing phosphorus from NSSD effluent
were the intermittent
nature of
the flow,
its
variable phosphorus content, and various
other factors which render process control difficult
for
this
effluent.
Adequate chemical mixing and treated effluent settling
times,
as well
as precise chemical dosage rates were felt
necessary
to effect phosphorus
removal
(R.
25
& 114—115).
The
engineer’s report
and
the laboratory bench
tests upon which
it
was based both considered only ferric chloride precipitation as
a
method
of control, but testimony indicates that the
considerations and costs are similar
for
the use of aluminum
sulfate
(Ex.
4,
pp.
5—1—5—2;
R 114).
The NSSD cost estimates would change based on
the above
revised phosphorus
removal estimates based on 1980—87
data, but
no effort was made
to do so.
The major costs
of phosphorus
removal are the capital
costs.
These do not change with revised
discharge flow and phosphorus removal estimates.
Only the annual
operating costs would change.
Basing revised overall cost
estimates
on the subsequent data would not yield annualized
per
unit phosphorus
removal costs very different from those presented
by NSSD.
88—416
—9—
North
Chicago
STP
The
NSSD
North
Chicago
STP
is
a trickling
filter plant with
a
3.5 MGD treatment capacity.
This plant collects wastes,
inter
alia,
from Abbott Labs and Great Lakes Naval Training Center
(“NTC”).
It merely acts
as
a “roughing” plant
because all its
treated wastes are pumped about
six miles
to the NSSD Gurnee STP
for
full treatment and ultimate discharge
to the Des Plaines
River.
No effluent phosphorus limitations apply to
that
discharge
(Cx.
4,
p.
3—2; R 47—48).
Combined stormwater inflow
to the North Chicago plant
enter with the Abbott Labs and Great
Lakes NTC streams,
go through bar screens
and
an overflow
diversion chamber, then are combined with treated effluent for
pumping
to the Gurnee plant for treatment
(R.63;
see Ex.
3).
The
pumping capacity to Gurnee
is 25.5 mgd,
but Gurnee could only
accept 12.0 MCD for treatment
in 1978—79
(Ex.
4,
p.
3—2
&
4—7,
R
80).
The North Chicago plant,
therefore,
cannot currently use
its full pumping capacity
to Gurnee.
Pumping
too much effluent
to the Gurnee plant
results in
an upset
of that plant’s
biological
system.
Gurnee
is currently only capable
of operating
at
a peak capacity of
25 MGD
to
30 MGD before
this occurs
(R.
80)
During extreme wet weather
flows any additional
flow beyond
the accepting capacity of Gurnee enters
a 1.8 MG retention basin
at North Chicago
(R.
63;
Cx.
4,
p.
3—2).
Additional excess flows
over this retention capacity are chlorinated
and discharged
to
Lake Michigan without
further treatment.
There is no
current
capability
for phosphorus removal
at North Chicago
and no land
available
at the plant
for expansion
of the overflow storage
capacity
(Cx.
4,
p.
3—2;
R.
85).
Any expansion
in overflow
storage capacity would have
to occur
at the NSSD Gurnee STP
(R.
47
&
67; see Ex.
4,
p.
3—2).
Nothing
in the record considers the
viability of discharging excess flows
at the Gurnee STP
to the
Des Plaines River instead of
to Lake Michigan.
The record testimony
indicates that for all
or part of the
years
1979 and 1981—83,
the North Chicago STP averaged
29
overflow events per year with an average
annual overflow volume
of
145.3 MG
(Ex.
4,
p.
4—10).
This
is based
on the NSSD
consulting engineer’s study.
Detailed data for overflow event—
days are available
for North Chicago similar
to that discussed
for Waukegan.
The North Chicago data
include 200 event—days,
of
which discharge
flow data
is available
for 176,
effluent
phosphorus data
for 171, and data for both criteria
for 152
event—days.
The detailed data on event—days
in the record
for
1980—87
(Cx.
4,
pp.
4—9;
Cx.
6
App.;
Ex.
7)
indicates an annual
average number
of
27 event—days,
but based
on the data for which
excess flow discharge volumes were available
(not
including the
1980 data
for
which much discharge volume information was not
recorded),
the annual average discharge volume was 81.3 MG for
the six and one—half years 1979
and 1981—87.
The highest year
indicated by the record
(1979)
saw a total effluent volume of
418
88—4 17
—10—
MG discharged to
the
lake
in
50 event—days
(Ex.
4, pp.
4—10).
For
those parts of the years
1980—87
for which the record
includes 176 individual event—days
with more detailed flow volume
data,
the largest single event—day occurred on December
3,
1982,
when
North
Chicago discharged
12.67 MG
to the lake,
and February
23,
1985, when 12.32 MG entered the
lake.
During
the week from
December
2—8,
1982,
seven event—days occurred for
a total
discharge of
49.39 MG.
Between February
21,
1985 and March
10,
1985,
18 event—days discharged
78.46
MG to the
lake.
Although
the occurrence
of event—days
is more sporadic at North Chicago
than at Waukegan,
they still
tend
to happen for periods from one
to several days running
(2.7 days average).
There appears no
definite pattern
to either the daily flow or
the phosphorus
content
of the discharges during these
periods.
A summary
tabulation of the annual totals
and averages follows:
Summary Tabulation:
Annual North Chicago STP Overflow DATA
Annual
Annual
Phosphorus
Year
Discharge
Events
14vera~~
1979
418 MG
50
3.0 mg/l
as P
1980
93**
24
3.7
1981
28.6
21
3.9
1982
82.5
27
3.3
1983
84.9
26
2.1
1984
97.9
44
2.7
1985
116.3
27
2.1
1986
114.2
25
1.7
1987
(6 mos)
3.8**
6
2.46
Total
(8.5 yrs)
942.4 MG**
251
——
Average
134.6
MG**
33
2.89 mg/l
as P
*
Indicates
average
total phosphorus based
on available data
only.
Some data were missing for
each of
nearly all years
**
Indicates total discharged volume for available data.
18 data
for
1980 and
5 data for 1987 were missing.
For this reason,
the
total flow and average annual
flow data do not consider 1980 and
1987 data,
leaving only
a 7.0
year base for
flow data.
Examination of the detailed 1980—87 discharge data
for which
discharge volumes were available indicates
that elimination of
smaller
discharges diminishes the number of discharges more
rapidly than it diminished
their
total volume.
The tabulation
below
is
similar
to that given above
for Waukegan.
Reference
is
made
to that narrative
for explanation.
The table follows:
88—418
—ii—
Numbers
and
Volumes of North Chicago Overflow Discharges by Event Size
Size of Event
Less
than
.25 MG
.25 MG to
.50 MG
.50 MG to 1.0 MG
1MG
to
2MG
2 MG to
4 MG
4 MG to
6 MG
6 MG to
8 MG
8 MG to 10 MG
Greater
10
MG
Totals
By
Number
of
Events
Number
Percent
Curn
12
6.8
6.8
14
8.0
14.8
23
13.1
27.8
32
18.2
46.0
40
22.7
68.8
26
14.8
83.5
19
10.8
94.3
5
2.8
97.2
5
2.8
100.0
176
100.0
By Category Volume
MG
Percent
Cum.
0.3
0.3
1.0
1.3
3.2
4.5
8.5
13.0
20.5
33.5
23.4
56.9
24.4
81.3
8.2
89.5
10.5
100.0
100.0
—
1.66
5.18
17.5
45.82
110.08
125.90
131.24
43.96
56.58
537.57
The mean event—day size indicated
by this data was 3.05 MG.
The
median
was
about
2.16
MG,
but
half
the
total
volume
discharged
was
in event—days of greater than
5.29 MG.
Elimination of the
first
10 MG of all event—days
reduces the number
of event—days
during this period
(August,
1980
through March,
1987
=
80 months
=
6.67
years)
from
176
to
5
(from
26
to
less
than
1
per
year,
average)
and the overall discharge volume from 537.57 MG
to 6.58
MG
(from 80.6 to
1.0 MG per year, average;
98.8
reduction).
Elimination of
the first
13 MG of each event—day eliminates
them
all.
The NSSD engineer estimated,
based on 1979—83 data,
that
certain improvements at the NSSD Gurnee plant would
reduce the
annual average number
of events
to seven and discharge volume
to
20.6
MG
(85.8
reduction).
The
respective
estimates
are
disparate, and they are significant
to later discussion.
The NSSD engineer
indicated that the annual average
phosphorus contents
of the discharges during 1979—83
ranged from
1.97 to 3.88 mg/l, with an overall average over the five years of
3.0 mg/i.
Examination of the 171 detailed data for
1980—87 for
which phosphorus
is available reveals
a
range of from 1.36 mg/i
to 4.57 mg/i,
with an average
of
2.77 mg/l
as
P.
A summary
tabulation of these data,
categorized by effluent phosphorus
content, and the associated percentage of discharges within each
category,
follows:
88—4 19
—12—
Number
of Event—Days Discharging Specified Phosphorus
in Effluent
Effluent Phosphorus Content
(rng/l as P)
Year
1.0
1.0—2.0
2.0—3.0
3.0—4.0
4.0—5.0
5.0
Thtal
1980
0
0
0
0
7
37
5
26
6 32
1
5
19
1981
0
0
0
0
2
10
14
67
3 14
2
10
21
1982
0
0
1
4
7
29
12
50
4 17
0
0
24
1983
1
4
10
40
13
52
1
4
0
0
0
0
25
1984
1
3
7
18
16
41
15
38
0
0
0
0
3w
1985
2
2
8
36
8
36
4
18
0
0
0
0
22
1986
4
25
8
50
1
6
3
19
0
0
0
0
16
1987
2
40
2
40
1
20
0
0
0
0
0
0
5
IOTAL
10
6
36
21
55
32
54
32
13
8
3
2
171
CUM.
10
6
46
27
101
59
155
91
168 98
171
100
—
During this entire period, only ten
(6)
of
the samples complied
with the effluent standard
of 1.0 mg/l
as
P applicable
to Lake
Michigan
discharges.
One
interesting
trend
indicated
by
this
data
is
that
the
effluent
phosphorus
content
of
North
Chicago
discharges appears
to decrease with each succeeding year.
The
highest individual datum submitted was 9.1 mg/i
(Cx.
4,
pp.
4—9;
Ex.
6 App.;
Cx.
7).
The record indicates that
a significant portion of the total
phosphorus discharged
in the North Chicago effluent was
in excess
of
the 1.0 mg/i Lake Michigan effluent standard.
The NSSD
engineer’s estimate indicates that the average annual total
phosphorus discharged from North Chicago
to Lake Michigan during
the period including part
or all
of 1979—83 was
3,635 pounds
(Cx.
4,
pp.
4—10
&
5—3)
——
about 2,422 pounds
(200 percent)
in excess
of what would have entered the lake had the effluent consistently
averaged 1.0 mg/i as
P.
The highest single year
indicated by
the
record was 1979, during which NSSD discharged 10,458 pounds of
phosphorus
to Lake Michigan
——
6,970 pounds
(200 percent)
in
excess of
a consistently 1.0 mg/i effluent
(Cx.
4,
pp. 4—10).
Analysis of
the
171 tabulated individual 1981—87 event—days
indicates that the North Chicago STP overflow discharges
in
excess of 1.0 mg/i total phosphorus
added an excess of
5,420
pounds of total phosphorus
to the lake
in violation of Section
304.123(a),
or an average excess of
810 pounds per year, when
factored
to account
for the 14.5
of event—days
for which
phosphorus data are missing.
The overall
total phosphorus
discharged during
the period was about 12,410 pounds when
factored
for
the missing data,
or
an annual average of 1,860
pounds
for
these
six and two—thirds
years.
The estimates based
on 1981—87 data are lower
than the NSSD engineer’s estimates
based on
1979—83.
This may partly result from
the trend towards
lower effluent phosphorus levels since
1983.
The NSSD engineer who studied
the phosphorus discharge
problem projected
an estimated capital cost
of $401,700 and an
annual
operating cost of $32,000
for
the installation of
a ferric
88—420
—13—
chloride
chemical
removal
system
under
the
current
operational
scheme.
This
is
about
$20
per
pound
of
phosphorus
that
the
system
would
remove
(Ex.
4,
p.
5—3).
The engineer
indicated that
the costs
for an aluminum sulfate
removal
system
would
be
similar
(R.
114).
The
record reflects
no planned improvements
for
the North
Chicago plant
that would impact
its phosphorus discharges.
The
current
201
Facilities
Improvements
Plan
for
the
Gurnee
STP
calls
for
an
increase in the treatment and overflow retention
capabilities
of that plant.
This would permit using
the transfer
pumps at North Chicago
to operate
at
up to their
25.5 MGD
capacity
(Ex.
4,
p.
3—2).
These improvements include
the
addition of
50 MG excess flow retention capacity by the beginning
of
1991
(R.
64
&
80).
They also
include staged increases
in
design
treatment
capacity,
as
follows:
from
the
current
13.8
MGD
to 17.25
~4GDby December,
1987;
to
19.6 MGD by December,
1988.
(R.
67—68
&
83).
The Gurnee STP currently receives an average
of
12.4 MGD for treatment
(R.
67).
When fully expanded,
the plant
will accept
a peak flow of
39.2 MGD
(R.
83).
The
addition
of
the
50
MG
retention
capacity
is
in
response
to the final Board Opinion
and Order
in PCB 85—208,
for the
purpose of
controlling North Chicago excess flow discharges
to
the lake
(R. 64;
see supra Footnote on page
1
re PCB 85—208).
The record
is unclear whether NSSD is otherwise fully committed
to the full plant expansion
to
19.6 MGD by December,
1988.
If
NSSD can operate
its North Chicago sewage transfer pump to Gurnee
at
its full capacity of 25.5
MGD,
as opposed
to
the current
maximum of about
12 MGD
(R.
80—81),
an additional
13.5 MGD can
transfer
to Gurnee before overflow occurs
to Lake Michigan.
It
was on these expansions that the NSSD engineer based all
his
phosphorus reduction and cost estimates.
The NSSD engineer who studied
the phosphorus discharge
problem estimated that these improvements would reduce
the
average annual amount
of phosphorus discharged from North Chicago
from 3,635 pounds to 515 pounds
(85
reduction)
(Ex.
4,
p.
5—
3).
Elimination of the first
13 MG from each discharge
in the
detailed 1981—87 data above eliminated
all discharges.
This
would mean
a 100
reduction
in the 1981—87 estimated annual
average of 1,860 pounds of phosphorus discharged
to the lake.
The NSSD engineer estimated
that ideal ferric chloride phosphorus
removal alone would reduce the North Chicago discharges
to 1,211
pounds per year
(67
reduction)
(Cx.
4,
p.
5—3).
Based on the
detailed 1981—87 data,
ferric chloride would have reduced
the
phosphorus discharged by the above—estimated annual average
excess
of
810 pounds,
to
a permissible discharge
of 1,050 pounds
(43.7
reduction)
(Cx.
4,
p.
5—3).
The detailed
1981—87 data
indicate that this combination of
flow diversion
and phosphorus
removal would
likely be unnecessary because diversion alone would
have eliminated
the phosphorus during this period.
For
comparative purposes,
these
two estimates
are tabulated below:
88—421
—14—
Comparison of NSSD and Estimated Phosphorus
Reductions by Method of Reduction
for North Chicago
Phosphorus Discharges
Phosphorus Reduction Method
NSSD 1979—83 Estimates
1980—87 Estimates
Existing Facilities
3,635 pounds
1,860 pounds
Chemical Removal Alone
1,211 pounds
1,050 pounds
Phosphorus
Reduction
67
43.7
201
Facilities
Improvements
515
pounds
No Discharges
Phosphorus Reduction
85
100
Both Methods Together
171 pounds
Phosphorus
Reduction
96
The NSSD estimates based
on 1979—83 data
indicate
a greater
reduction by chemical reduction,
but a
lower
reduction by flow
diversion,
than do
the detailed
1981-87 data.
The
NSSD
engineer
estimated
the
annual operating cost of the
ferric chloride removal system on
this reduced
overflow volume
would amount to $7,500,
which translates
to $134 per pound of
phosphorus
removed
from
the
effluent.
Such
a
system
would
remove
only an average additional
344 pounds
of phosphorus, permitting
only
171
pounds
to
discharge
to
Lake
Michigan.
These
treatment
estimates assume consistent treatment
(Cx.
4,
p.
3—2).
The same
operational constraints
that make
the Waukegan effluent difficult
to treat for phosphorus
(i.e.,
intermittent, variable flow;
variable effluent phosphorus content,
etc.)
apply to North
Chicago
(R.
114—115),
but
the North Chicago effluent does have
a
more consistent
and higher phosphorus content than Waukegan.
No
effort was made to estimate removal costs based
on 1981-87 data
for
the same reasons
this was not done
for the Waukegan cost
estimates.
Impact
of
the
Phosphorus
Discharges
on
Lake
Michigan
The engineering firm retained by NSSD to study the
environmental
impact of
its phosphorus discharges made visual
inspections of the lake,
collected water samples and analyzed
them
for phosphorus,
and performed
a literature study of the
pollution by and impact of phosphorus
on the lake.
Nothing
in
the record correlates phosphorus loading with algal
bloom or
chlorophyl content of
the
lake.
No data exist
in the record
which indicate the algae or chlorophyl
content
of the lake
in the
areas of
the NSSD ccaukegan and North Chicago excess flow
outfalls.
The NSSD consulting engineer concluded that no
evidence indicates
an adverse environmental
impact due to the
phosphorus content
of these effluents.
The near—shore area of Lake Michigan
is mesotrophic
along
the
north suburban shoreline as
a result of
local phosphorus
contributions
(Cx.
8,
p.
18).
The existing
ambient water quality
88—422
—15—
standard
for phosphorus
in the lake
is 0.007 mg/l
(as P).*
35
Ill.
14dm. Code
302.504.
An
international treaty with Canada,
the
Great Lakes Water Quality Agreement of
1978,
imposes
a
1 mg/l
total
phosphorus effluent limitation on
“all plants discharging
more than one million gallons per day
to achieve, where necessary
to meet
the loading allocations
...,
or
to meet local conditions,
whichever
are more stringent
....“
Great Lakes Water Quality
Agreement of 1978
,
Ann.
3,
par.
2(a),
International Joint Com.
(Nov.
22,
1978).
The target “future phosphorus load”
(i.e.,
the
loading allocation)
for Lake Michigan
is indicated as
5600 metric
tons
(6170
short tons)
per year.
Id.
at par.
3.
The 1981 and
1982 estimated phosphorus
loads
to the lake were 4091 metric tons
and 4084 metric
tons,
respectively
(Cx.
4,
p.
4—2).
The
applicability of this treaty to NSSD intermittent discharges
is
uncertain.
The Lake County contributions of phosphorus
to Lake Michigan
are significant,
and the NSSD portion of that contribution
is not
insignificant.
Lake County comprises 0.08 percent of
the
total
shoreline
of Lake Michigan with 31 miles of shore
(Cx.
8,
pp.
3
&
30),
but
it contributes 0.97
of the total phosphorus
loading
to
the
lake.
An
estimate
of
the
total
phosphorus
loading
from Lake
County
is
as follows
(Ex.
8,
pp.
27—30):
Phosphorus Source
Phosphorus Contribution
County
L Michigan
Stormwater
13,400 pounds
6.3
0.061
Beach
Erosion
155,000 pounds
72.5
0.705
Baseflow
25,800
pounds
12.1
0.117
Atmosphere
6,100 pounds
2.9
0.028
Other Runoff
1,660 pounds
0.8
0.008
NSSD
Overflow (1982)
11,800 pounds
5.5
0.054
Total
Lake
County
213,760 pounds
100.0
0.972
Total
Lake
Michigan
(1978)
22,000,000
pounds
—
100
The Lake County beach erosion contribution
is the most
significant source of phosphorus
from that county,
but
it
contains
less than three percent available phosphorus.
This
decreases
the environmental significance of its contribution.
The next most significant sources
of phosphorus are baseflow,
from groundwater,
and stormwater runoff.
The NSSD overflow
discharges contribute
5.5 percent of the overall
Lake County
phosphorus contribution, or 0.05
of the overall
lake loading.
Phosphorus levels
in the lake,
off Lake County,
did drop during
1973—83,
and the near—shore water quality was improved with
respect
to phosphorus
since elimination of continuous discharges
from NSSD treatment plants
(Ex.
8,
pp.
19
&
37).
*
See infra
footnote on page
16
88—423
—16—
The Lake
Michigan
Water
Quality
Reports
indicate
that
high
percentages of samples collected at
ten Lake Michigan sampling
stations from the Chicago
River north
to Waukegari Harbor violated
the water quality standard
for
total phosphorus.
The overall
rates
of violations
at all
ten stations were
33
in
1982,
37
in
1983,
43
in 1984,
and 39
in
1985
(Cx.
4,
p.
4—1;
Cx.
9,
p.
16;
Ex.
10,
p.
19;
Ex.
11,
p.
19).
Only six
of
these sampling
stations were
near
the Lake County shoreline,
however, and only
three were near the NSSD overflow outfalls
(See
Cx.
4,
p.
4—4).
The reports did not include station—by—station violations rates,
and the detailed data were presented
in a two—digit format
that
only permits approximation
of the violations
rates
for the
individual
Lake County stations.
Any total phosphate data of
.02
mg/i
or lower are considered herein within the standard,
and any
of
.03 mg/l or higher are deemed
to have “clearly violated”
the
standard.
*
The detailed water quality survey data for
1981
through
1985
(Cx.
4,
p.
4—3;
Ex.
9, pp.
88—93);
Cx.
10, pp. 99—104;
Cx.
11,
pp.
120—125)
indicate
that
56 of 198 samples
(28)
collected
at
specified points nearest
to the Lake County shoreline clearly
violated
the Lake Michigan water quality standard of
0.007 mg/i
as
p.
35
Ill.
14dm. Code 302.504.
The
relevant sampling points
and their approximate
locations were the following:
SN
1 mile offshore from Great Lakes N~IX
6N
1 mile
offshore
from
midway
between
Great
Lakes
N’It
and
Waukegan
Harbor
7N
1 mile offshore from Waukegan Harbor
8N
4 miles offshore from Lake Forest
9N
5 miles offshore from Highland Park
iON
3 miles offshore from Glencoe
The sampling points
5N,
6N, and 7N are nearest
the NSSD Waukegan
and North Chicago overflow discharge points, but are also nearest
the shore.
A total of
31 out of
99
of these near—shore, near
NSSD samples
(31)
clearly violated the standard.
The other
three off—shore sampling points away from NSSD outfalls clearly
violated the standard
in
25
of 99 samples
(25).
There
is no
real statistical
significance
in the increase
in the rate of
clear violations
nearer
the NSSD overflow outfalls than at points
8N,
9N,
and iON.
It
is difficult
to attribute the increased
rate of clear
violations
to the NSSD discharges,
but the data do not permit
*The
record indicates some confusion over
the phosphorus water
quality standard.
The standard
is 0.007 mg/l
as phosphorus
(P)
or
0.021
as phosphate
(P04).
Convert phosphorus
to phosphate by
Using
a multiplication
factor
of 3.066.
Convert phosphate
to
phosphorus by using
a multiplication
factor of 0.3261.
88—4 24
-17-
dismissing
this possibility.
Statistical analysis
of these data,
assuming
a normal distribution,
reveals the following with regard
to the mean phosphorus content
of
the lake water
at each station:
Station
Phosphate Content
(mg/l as PO4)*
Probability
Obs. “Clear
(N.to S.)
Mean
Lower 95
C.L.
Upper 95
C.L.
of Violation
Violations”
7N
.025
.017
.033
57
30
6N
.022
.016
.027
51
33
SN
.021
.016
.026
51
30
Avg. Near
.023
.019
.026
54
31
8N
.022
.015
.028
51
24
9N
.021
.016
.027
51
24
iON
.019
.015
.023
44
27
Avg. Away
.021
.017
.024
49
25
Avg. All
.022
.019
.024
52
28
*~notes
that
the
conversion
from
phosphate
to
phosphorus
involves
multiplication
by
0.3261.
To
convert
from
phosphorus
to
phosphate
multiply
by
3.066.
The “probability of violation”
is the probability that
a random
sample would violate the Lake Michigan 0.007 mg/i
as
P water
quality standard.
The imprecise nature
and paucity of the two—
digit data probably contribute significantly to
the vast
differences between
the
calculated
probability
of
violation
and
the observed rates of “clear violation.”
Despite the lack of any
statistical differences between the mean phosphorus contents
at
these six monitoring stations,
the trend
is for a
regular
decrease
in
the mean phosphorus content and the probability of
violation as one moves southward from station to station,
beginning
at Waukegan Harbor.
The record includes no direct
indication
that NSSD
phosphorus discharges cause
or contribute
to water quality
standard violations.
Estimates of phosphorus contributions are
possible
for comparative purposes, however,
using certain record
estimations of the near—shore mixing
zone.
These estimates
indicate a great potential
for the larger NSSD discharges with
higher phosphorus contents to
at least contribute to such
violations.
The near—shore mixing zone used by the Northeastern
Illinois Planning Commission was a 2,000
foot wide strip of water
along the shore with an average depth of 10
feet.
They used this
to estimate the impact of pollutant loadings
to the lake
(Cx.
8,
p.
23).
This translates
to
a volume of approximately 470
MG
Within
a 2,000
foot radius of an outfall
on
the shore.
Assuming
complete mixing
within this
zone,
the following calculated
Contributions
to
the
total phosphorus content of
the lake water
within this
zone result:
88—425
—18—
Calculated Contribution
to Lake Phosphorus
Content (mg/i as P)
in
2,000 Foot Zone
Discharge
Phosphorus Content of Effluent (mg/i as P)
Volume (MG)
1.0
1.3
2.0
3.0
5.0
1
.0021
.0028
.0043
.0064
*
.0106
2
.0043
.0055
*
.0085
*
.0128
*
.0213
5
*
.0106
*
.0138
*
.0213
*
.0319
*
.0532
10
*
.0213
*
.0277
*
.0426
*
.0638
*
.1064
~
that
the effluent contribution alone violates the water quality
standard of 0.007 mg/l as P.
If this zone
is extended to
a one—mile radius with
an average
depth of
20
feet,
the volume defined increases
to 6,550
MG.
The
phosphorus contributions with ideal mixing within this zone
then
become:
Calculated Contribution to Lake Phosphorus
Content
(rr~/las P)
in One Mile Zone
Discharge
Phosphorus Content of Effluent (rr~/l as P)
Volume
(MG)
1.0
1.3
2.0
3.0
5.0
1
.0002
.0002
.0003
.0005
.0008
2
.0003
.0004
.0006
.0009
.0015
5
.0008
.0010
.0015
.0023
.0038
10
.0015
.0020
.0031
.0046
*0076
20
.0031
.0040
.0061
*0092
*0153
*Denotes that the effluent contribution alone violates
the water
quality standard
of 0.007 mg/l
as P.
These estimates do not account
for the background phosphorus
content of the local lake water, which appears
to average near
the water quality standard
in
the near-shore area off Lake County
(See Ex.
9;
Cx.
1.0;
Ex.
11).
It
is worthwhile
to remember
in
examining these tables what the record indicates with regard to
Waukegan STP and North Chicago STP overflow discharges.
The
average discharge volume
for
a Waukegan event—day was 12.2 MG,
with
a maximum single event—day of 67.7 MG, during
1980—87.
The
average phosphorus content of
this effluent was 1.14 mg/l
as P
during
this period,
with
a maximum of 2.70 mg/i.
The mean North
Chicago event—day was 3.05 MG, with
a maximum of
12.67 MG.
The
average North Chicago total phosphorus content was 2.77 mg/i as
P, and the maximum was 9.08 mg/i.
The NSSD consulting engineer concluded that the
impact of
NISSD phosphorus discharges
on the lake was unknown,
hut that
it
Warranted further monitoring
and study.
The consulting engineer
recommended that NSSD should develop and implement
a program of
88—426
—19—
consistently sampling and
testing
its overflow effluent and the
receiving
lake water
in the vicinity of
its discharges
for
phosphorus.
He
further
recommended
that
NSSD
should
reevaluate
the need
for phosphorus controls
if a negative
impact
is
determined
(Cx.
4,
pp.
1—2
& 1—3).
The engineer concluded that
implementing
some
form of phosphorus control
in addition to
implementing
the prospective 201 Facilities Improvements
would
have
no more than
an insignificant effect on
lake water quality
(Cx.
4,
p.
6—1).
The engineer made no comment with regard
to
implementing phosphorus controls
or the environmental
impact
if
the 201 improvements do not occur.
The engineer’s projections of
estimated
annual phosphorus loadings
to
the
lake and the
calculated loadings based
on 1960—87 detailed data were tabulated
in the above discussions.
Phosphorus loadings
to
the lake are significant
to
the
extent
that they contribute
to
a water quality violation or have
an adverse environmental impact by promoting algal
bloom
and lake
eutrophication.
The record hints
that some
reduction
in
phosphorus
loading
to the lake yields
a calculable decrease
in
biornass, but the nature of
the relationship
is not given
(See Cx.
11, pp.
56—58).
This could mean that
increased phosphorus
loadings might
result
in
a concommitantly increased algal
bloom.
This could contribute
to
the natural eutrophication of
the lake.
The record
includes data for the algal and chlorophyll
a contents of
the lake,
but not for
an area near
the NSSD
outfalls,
and not
in
a form that can relate
to biomass and
phosphorus.
(See Cx.
9, pp.
49—58;
Cx.
10,
pp.
55—63;
Ex.
11,
pp.
51—61).
The NSSD consulting engineer speculated
that the
NSSD phosphorus discharges would have only
a negligible impact on
the lake “if the
201 Facilities Plan improvements are
implemented” over what would occur
if NSSD instituted phosphorus
removal
(Cx.
4,
p.
1—2).
The record supports
this conclusion,
but
in
a slightly altered
form:
the facilities expansions that
would allow excess
flow diversion away from the lake would
eliminate more phosphorus
to the lake than would chemical
removal
alone.
NSSD Proposal and Agency Recommendation:
NSSD proposes
in
its comments
to the December
24, 1987
Hearing Officer Order
a numerical
limit
for
its phosphorus
discharges,
as follows:
Waukegan:
Limit
(mg/i
as
P)
=
4.96
—
(1.5
/
23
x event—days
per month)
North Chicago:
Limit (mg/i as P)
=
5.96
—
(1.5
/
23
x event—days
per month)
(Comments
from
the North Shore Sanitary District).
This
numerical standard would make
the effluent limitation
a function
of the number of event—days,
as follows:
88—4 27
—20—
Event—Day
Phosphorus
Effluent
Limitation
(mg/I
as
P)
Month
Waukegan
North
Chicago
1
4.9
5.9
7
4.5
5.5
30
3.0
4.0
In
its
response, NSSD reaffirms facts adequately supported by the
record:
effluent phosphorus content,
the number
of
event—days,
and the overflow discharge volumes are dictated by factors beyond
the control
of NSSD.
The Agency has not commented
on this
proposed numerical phosphorus limit.
(See “Agency’s Response
to
Hearing Officer Order” dated January 25,
1988 at p.
2).
The
Agency has proposed an alternative approach that appears more
fully supported by the record.
The
Agency
proposes
adoption
of
indirect
discharge
volume
limits.
It acknowledges
that
NSSD
has
no
control
over
the
amounts and patterns
of precipitation,
but focuses
on
the fact
that NSSD does have control over the operation and expansion of
its
plants.
The
Agency
suggests
that
this
Board
should
require
NSSD
to
provide
peak
wet
weather
treatment
at
its
Waukegan
STP
of
twice
its design average flow once the proposed
201
Facilities
Improvements expansion occurs.
The Agency does not comment on
the fact that NSSD has not yet committed
to undertaking the 201
improvements
at Waukegan.
The Agency feels that certain plant
improvements at Gurnee required by the February
5,
1987 Opinion
and Order
of this Board
in PCB 85—208 will sufficiently reduce
overflow discharges from the North Chicago plarit.*
The Agency
concedes “that attempting phosphorus removal
from these sources
is
impractical
and probably not cost effective.”
(“Agency
Response
to Hearing Officer Order”
at
3).
The Agency proposes that this Board require NSSD to monitor
the lake
for phosphorus on
a continuing basis.
It proposes
monitoring weekly samples for phosphorus from certain local
beaches near the NSSD CSO outfalls:
Waukegan North, Waukegan
Central,
and Foss Park.
It adds Illinois Beach State Park and
Lake Bluff
for data on background phosphorus levels
in
the
lake.
The Waukegan North site
is about
1,700
feet south of
the
Waukegan
CSO
outfall,
and
the
Waukegan
Central
site
is
about
2900
feet
south
of
this
outfall
(Cx.
5,
~.
3—3).
Illinois
Beach
State
Park
is over
a mile north
of the Waukegan outfall
(Cx.
I).
The
Foss Park sampling site
is about
1,800 feet south of
the North
Chicago CSO outfall
(Cx.
6,
p.
3—3).
Lake Bluff
is about
three
miles south
of North Chicago
(Cx.
1).
The Agency recommends
testing the beach samples
for phosphorus
for two days following
overflow events occurring during warm weather,
and as soon as
*
See
supra
footnote
on
page
1.
88—428
-21-
possible after events during
the non—swimming months.
The Agency
further recommends offshore sampling and testing
for three events
per year,
with one set of additional background samples during
each spring,
summer,
and fall,
at least
two weeks after any
discharges.
It suggests that all event monitoring
should occur
within
24 hours of any event, where possible,
and that any
testing
of water samples should
include fecal coliform.
The
Agency finally recommends phosphorus,
BaD,
TSS,
and volatile
solids testing of
sediment samples, but
it does not recommend
a
sampling frequency.
II .Discussion
This
is
a troublesome proceeding.
Although the record
supports certain conclusions,
information
is lacking
which could
remove
all
hesitation
in
adopting
a
site—specific
phosphorus
rule
for
the
Waukegan
and
North
Chicago
intermittent
discharges.
The
following conclusions
are made based on
the record
in this
proceeding:
1.
The costs
of
chemical phosphorus
removal
are very high
for both Waukegan and North
Chicago
discharges.
They
increase
to
exorbitant
if
certain
proposed
201
Facilities
Improvements
are
implemented
by NSSD;
2.
The intermittent nature
of the discharges
would
likely
cause
process
control
problems and less than optimal phosphorus
removal,
resulting
in
discharges
in
excess
of
the
existing
effluent
limitation
despite
good
engineering
practice;
3.
Merely
focusing
on
a
numerical
effluent
limitation
can
ease
the
burden
of
performance
monitoring
and
enforcement,
but
it would
likely not optimally reduce
phosphorus
discharges
to
Lake
Michigan.
It
would
also
ignore
the
fact
that
the
phosphorus concentrations
in the overflow
effluents
are probably beyond
consistent
control;
4.
Statistically,
the
average
annual
phosphorus
content
of
the
Waukegan
effluents
have
not
varied
appreciably
during
1981—87,
but were slightly higher
during
1979
and
1980,
with
an
overall
annual
average
concentration
of
1.2
mg/i
as
P
during
the
period
1979—87.
During
this period,
99
of
samples
measured
2.5
mg/I as
P or
less;
88—429
—22—
5.
Statistically,
the
average
annual
phosphorus
content
of
the
North
Chicago
effluents
significantly
decreased
since
about
1983,
and
showed
greater
variability than
those
of Waukegan.
The
annual
average
phosphorus
contents
was
3.5
mg/i
during
1979—82
and
2.2
mg/i
during
1983—87,
with
an
overall
average
of
2.9
during
the
entire
period
1979—
87.
During
1980—82,
95
of
samples
contained total phosphorus
of
5.0 mg/l as
P
or
less,
but 100
of
samples contained
less than
4.0 mg/i
as
P during 1983—87;
6.
The
individual
volumes,
annual
numbers,
and
annual
total
volumes
of
overflow
discharges
from
both
Waukegan
and
North
Chicago
have
shown
great
variability
during
1980—87,
but
1985
and
1986
(the
last
two
years
for
which
a
full
years’
data
were
available)
had
the
highest
total
annual
volumes
for
both
plants
arid
the
highest
number
of
events
at
Waukegan.
No definite
increasing
trends
are
yet
apparent
for
these
criteria;
7.
The
record
indicates
no
significant
correlations
among
any
of
the
following
variables:
effluent
phosphorus
content,
overflow
discharge
volume,
or
event
frequency;
8.
No basis exists
in the
record
to support
adoption
of
NSSD’s
proposed
scaled
phosphorus
effluent
limitations
of
from
3.0
to 4.9 mg/i as
P
for Waukegan or
from
4.0
to 5.9 mg/i
as P
for North Chicago;
9.
The greatest
reductions
in
overall
total
phosphorus
loading
to
the
lake
would
result
from
diversion
of
overflow
discharges
to
either
alternate
treatment
or
retention
facilities.
Elimination
of
the
first
14
MG
of
each
Waukegan
discharge
during
1980—87
for
which
detailed
data
exist
in
the
record
would
have
eliminated
about
71
of
the
total
volume
discharged
during
this
period.
This would
likely have reduced
the
total
phosphorus
discharged
by
at
least
a
similar
amount.
Similar
elimination
of
the
first
13
MG
of
all
North
Chicago
88—430
—23—
discharges
would
have
eliminated
all
discharges
to
the
lake;
10.
Operation
of
the
North
Chicago
effluent
transfer
pump
at
its
25.5
MGD
capacity,
instead
of
its
current
maximum
capacity
of
about
12
MGD
results
in
an additional
capacity
of
at
least
13
MGD
which
could
transfer
overflow
volume
to
the
NSSD
Gurnee
plant.
Construction
of
a
50
MG
retention
basin
at
Gurnee
by
January
1,
1991,
and
expansion
of
that
plant’s
design capacity
from 13.8 MGD
to 19.6 MGD
(from
a peak
capacity
of about
28 MGD
to
about
39
MGD)
by
January
1,
1989,
will
permit
operation
of
the
North
Chicago
effluent
transfer
pump
at
its
full
capacity;
11.
Expansion of
the Waukegan plant’s current
design
capacity
of
19.6
MGD
and
peak
capacity
of
about
30
NIGD
to
a
design
capacity
of
22
MGD
and
peak
capacity
of
44
MGD will
result
in
an
additional peak
capacity
of
14
MGD
available
to
treat
wastewater
before
it
is diverted
to
that
plant’s
38
MG
overflow
retention
system
and
to
the
lake.
NSSD
proposes
such
expansion as
a part of
its 201 Facilities
Improvements
Plan
and
projects
the
possible
completion
of this expansion
in
1992 or
1993,
but
is not yet committed
to
implementing
it;
12.
The
record
amply supports providing
some
form
of
site—specific
relief
according
to
the Agency recommendation which
seeks
to
limit
phosphorus discharges
by
diversion
or
elimination
of
excess
flows
to
the
lake;
13.
According
such
site—specific
relief
predicated on diversion or elimination of
Waukegan
excess
flows
would
require
the
implementation
of
the
plant
improvements
that would allow
this to occur;
14.
Additional
land
is
unavailable
at
Waukegari
and
North
Chicago
to
construct
additional
retention
capacity
at
either
facil ity;
88—43 1
—24—
15.
The
estimates
of
environmental
and
water
quality
impact
of
the
overflows,
discharge
and
the
costs
of
phosphorus
control
submitted by NSSD,
are predicated
on
the
full
implementation
of
the
201
Plan
for
Waukegan
and
expansions
at
Gurnee;
16.
The
frequency
of
water
quality
standards
violations
along
the
Lake
Michigan
shoreline
in the vicinity of
the Waukegan
and
North
Chicago
excess
flow
outfalls
is
significant,
and
the
lake
is
inesotrophic
in
that
area
with
an
average phosphorus
content
very
near
the
water
quality
standard,
but
the
average
phosphorus
content
and
frequency
of
standard
violations
have
decreased
since
NSSD
eliminated
its
former
continuous
effluents discharges
to the lake;
17.
Nothing
in
the
record
permits
the
conclusion
that
either
the
Waukegan
or
North
Chicago
overflow
discharges
directly
arid
significantly contribute
to
or
cause
water
quality
violations
or
cause
an adverse
impact on the lake;
18.
Nothing
in
the
record
permits
a
conclusion
that
neither
the Waukegan nor
the
North
Chicago
overflow
discharges
contribute
to
the
frequent water
quality
violations near
the Lake County shore
and
the
inesotrophic condition
of
the
lake
in
that area; and
19.
Future
monitoring
of
lake
water
quality
for
phosphorus
in
the
vicinity
of
the
Waukegan
and
North
Chicago
outfalls
is
feasible
and
reasonable.
This
could
readily
include
samples
collected
at
areas
away
from
the
outfalls
to
provide
background
quality
information,
so
that
detection
of
whether
the NSSD discharges
actually
do
cause
or
contribute
to water
quality
violations
or
have
an
adverse
impact
on the lake is possible.
This record presents
many
problems
by
raising
several
questions
that
it
fails
to provide adequate information
to
answer.
Many
of
these
are
listed
below:
88—432
—25—
1.
Do
any
lower
cost alternatives
exist
for
phosphorus
removal
to
those
mentioned
in
the
record?;
2.
What
is
the
feasibility
of
transferring
the
untreated
overflow
effluent
for
discharge
in
the
Des Plaines
River
along
with
the treated effluent?;
3.
What
has
occurred
and
where
in
the
NSSD
system
which
has
resulted
in
a
significant
reduction
in
the
phosphorus
content
of
North
Chicago
effluent?;
4.
Why
were
the
annual
overflow
effluent
volumes
significantly
increased
for
both
plants
during
1985—86,
and
what
caused
the
increased
number
of
events
at
Waukegan?;
5.
Is there any correlation between rainfall
and
the
occurrences
and
volumes
of
overflow events?;
6.
How did NSSD derive
the formulae for
its
proposed structured limits?;
7.
By
what
means
did
the
NSSD
consulting
engineer
derive
his
estimates
of
reductions
in
overflow
discharge
event
frequency
and
volumes,
and
what
impact
will
various
changed
circumstances
have
on
the
estimates
of
the
frequency
and
volumes,
such
as
revised
expansions
at
the
plants,
increases
in
service
areas,
an
increase
in
high
flow
inflow
in
the
Gurnee
STP
service
area,
retention
basin
down time for service, etc.?;
8.
What
is
the
cost
of
the
201
Facilities
Plan
improvements
at
Waukegan?;
and
9.
What alternative actions can NSSD
take
to
reduce
phosphorus
loadings
to
the
lake
if
additional information later
reveals
that
its
discharges
cause
or
contribute
to
water
quality
violations
or
cause
an
adverse impact on the lake?
The Board invites comments from any interested persons during
the
First Notice period on these
issues and their
prospective effects
on this site—specific rule.
88—4 33
—26—
The
record
does
no~ support
a
conclusion
that
NSSD’s
overflow
discharges
to
Lake
Michigan
directly
and
significantly
cause
or
contribute
to
violations
of
the
applicable
water
quality
standards.
The
record,
however,
does
not
support
a
conclusion
that
these
discharges
have
no
impact
on
water
quality.
What
the
record
does
indicate
is
this:
Any
adverse
effect
of
these
discharges would best be minimized
by reducing the frequency and
volumes of
their occurrence,
rather than by merely attempting
to
limit
the phosphorus concentration
in the existing discharge
flows.
The Board,
therefore, concludes
that NSSD attempts
at
compliance
with
the
existing
effluent
limitation
by
chemical
phosphorus removal would not be technically feasible and
economically reasonable, and would likely result
in little or
no
improvement
in Lake Michigan water quality over what
is possible
if NSSD were
to operate its system
in compliance with
a site—
specific rule designed
to minimize phosphorus discharges by
alternative means.
This Board will not grant
the NSSD proposed structured
numerical
limit.
First,
we
observe
that
NSSD
did
not
propose
an
alternative
rule
in
its
original
petition,
it
merely
requested
the
non—applicability
of
the
existing
rule.
We
next
observe
that
NSSD
first proposed its structured numerical
limit
in
its
response
to comments by the hearing officer made at
the public
hearing.
We also note that NSSD offered
no support
for
its
proposed rule,
and
it remains unsupported by the record.
Finally,
comparison with the record phosphorus data indicates the
proposed structured limits would
impose ceilings on effluent
phosphorus contents
far
in excess of what one could reasonably
anticipate.
If this Board wants
to impose
a numerical effluent
phosphorus
limitation, the
record must adequately support
that
limitation.
In this case, without
the guidance of either NSSD or
the
Agency,
this Board would have to independently derive
a more
reasonable
numerical
limitation.
If this Board were
so inclined,
such
a limitation would
be based on the annual average and peak
phosphorus contents indicated by the record.
It would allow
continued overflow discharges without violation, but would not
permit degradation of effluent quality.
In deriving such
a
standard, more recent trends would predominate
where
they
conflict with prior
indications of
the effluent data.
By this
method,
the Board would most likely adopt
the following total
phosphorus effluent limitations:
Waukegan STP
2.5 mg/l maximum
1.3 mg/i annual average
North Chicago STP
4.0 mg/i
maximum
3.0 mg/l annual average
These
limitations
would
adequately
accommodate
the
current
effluent qualities
of both plants without permitting effluent
88—434
—27—
quality
degradation.
The
Board
invites
any
interested
party
to
comment
during
the
first
notice
period
on
the viability and
desirability
of
such
a
numerical
limit.
Whereas such
a numerical effluent limitation would not allow
degradation of
the status quo, neither would
it foster
improvement
in
the
phosphorus
water
quality
of
an
already
degraded part
of the lake.
This Board believes adoption of
the
Agency’s approach
is the best
option
available,
with
only
minor
modifications:
1.
It would
seek additional
data
collection
for
possible
future
regulatory
action,
should
further
study
reveal
that
NSSD
overflow discharges do,
in
fact,
cause
or
contribute
to
water
quality
violations
or
cause
an
adverse
impact
on
the
lake;
and
2.
It
would
require
implementation
of
the
201
Facilities
Improvements
at
Waukegan
to attain
the benefits NSSD projected
in
its
arguments
in
favor
of
site—specific
relief.
The required sampling
and testing would include criteria
to
monitor ambient and
local
lake water quality,
rainfall,
effluent
quality, and local sediments near the outfalls.
In addition to
the
submission
of
the
testing
data,
NSSD
would
also
submit
records
of
the
dates
and
volumes
of
each overflow discharge,
the
volumes
of sewage transferred
from North Chicago
to Gurnee, and
the volumes of sewage held in each retention basin each
day.
Data on fecal coliform counts
to be collected along with
the lake
water phosphorus data should indicate the presence
of raw sewage
effluent.
This Board believes this supplemental data will not
only assist the Agency in monitoring NSSD compliance with
this
rule,
but would
also aid
it and the Board
in detecting possible
future contributions
to water quality violations.
These data
would further help determine
a potentially more effective
regulatory structure
if one is later found necessary.
We leave
to the Agency the details of the required data
submissions, but based on its understanding of the Agency’s
Recommendation, this Board will require submission of
the
following data at the indicated intervals:
Local
and Ambient Beach
Water
Quality
—
Total
phosphorus
and
fecal
coliform,
on
at
least
a
weekly
basis
between
March
1
arid December
1,
to
be
collected
at
a
single
selected
site
at
the following locations:
Illinois Beach State Park,
Waukegan North Beach,
88—435
—28—
Waukegan
Central
Beach,
Foss Park,
and
Lake Bluff.
Immediate Overflow Event Impact on Beach Water
Quality
—
Total phosphorus and
fecal coliform,
one
sample
one day
following
and
one
sample
two
days
following
each
overflow
discharge
from Waukegan
in
excess
of
9
MG within
a
24—
hour
period,
to
be
collected
at
a
single
selected site at
the following locations:
Waukegan North Beach, and
Waukegan Central Beach;
One
sample
one
day
following
and
one
sample
two
days
following
each
overflow
discharge
from
North
Chicago
in
excess
of
2
MG
within
a
24—hour
period,
to
be
collected
a1
a
single
selected site
at the following location:
Foss Park;
Provided,
however,
that
the selected
sampling
site
for
weekly
ambient
and
local
water
quality
is
the
same
corresponding
selected
site
for
the
immediate
overflow
event
impact
on
water
quality
samples;
and,
further
provided,
that
the
immediate
overflow
event
impact
sample
will
obviate
a
weekly
ambient
and
local
water
quality
sample
during
that
same week
at
that same site,
and
no more than
a
single
sample
shall
be
required
at
any
single selected site
in any single day.
Background
Offshore
Water
Quality
—
Tot~àl
phosphorus
and
fecal
coliform,
one
sample
during March,
April,
or May;
one sample during
June,
July,
or
August;
and
one
sample
during
September,
October,
or
November,
at
least one
week
following
the
most
recent
overflow
discharge from the corresponding facility,
and
collected
at
a
point
2,000
feet
directly
offshore from the following outfalls:
Waukegan STP, and
North Chicago STP.
Immediate
Event
Impact
on
Offshore
Water
Quality
—
Phosphorus
and
fecal
coliform,
one
sample
collected
one
to
two
days following an
overflow
discharge
from
the
corresponding
facility,
and collected
at
a
point
2,000
feet
directly offshore from the following outfalls:
88—436
—29—
Waukegan
STP,
and
North
Chicago
STP.
Effluent
Quality
—
In
addition
to
any
monitoring
currently
required
by
the
Agency,
NSSD
must
consistently
report
the
volume
discharged
and
the
effluent
total
phosphorus
content
for
each day discharge occurs.
Rainfall
—
Daily
rainfall
amounts,
to
be
recorded
at
each
of
Waukegan
STP
and
North
Chicago
STP.
This
Board
will
not
adopt
a
sediment
sampling
and
testing
requirement
in the absence of further clarification and
justification.
The
NSSD
engineer,
the
Agency,
and
this
Board’s
review of
the record have each stressed the importance
of
continued
monitoring
to
determine
more
fully
the
impact
of
NSSD
phosphorus
discharges
to
the
lake.
The
full
monitoring
requirements
shall
take
effect
with
this
rule.
In
addition
to
the
Agency
data
submittal
requirements,
the
Board’s
interest
in
this
matter
prompts
it
to
require
NSSD
to
submit
the
collected
data,
together with annual summaries of the data,
in
a
comprehensive
report
to
this
Board
for
the
years
1987
through
1991 on or
before April
1,
1992.
The detailed collected data
to be submitted
in the
comprehensive report
to the Board
shall include,
at
a minimum,
all data collected
for each of the following criteria:
overflow
events by date,
overflow volume discharged by date and source,
and overflow effluent total
phosphorus content by date and
source,
and
background
offshore
water
quality,
immediate
overflow
event offshore water quality impact,
immediate overflow event
beach water quality impact, and local
and ambient beach water
quality data for total phosphorus contents and fecal
coliform
counts by sample collection date and location,
as each of these
sampling criteria are described above.
These collected data
shall also include
for
the Waukegan, North Chicago, and Gurnee
plants,
the
following
by
plant
and
date:
the daily rainfall
amounts,
the total daily
flows receiving full treatment,
and the
maximum daily volumes held
in the respective retention basins.
For North Chicago,
the data shall include
the maximum daily
effluent transfer
rate
to Gurnee
and
the
total
daily
volume
so
transferred.
The annual summaries shall
include the total volumes
discharged,
the number of overflow events occurring
and the
average effluent phosphorus concentrations
for the Waukegan and
the North Chicago overflow discharge
facilities
for each of the
years
1987 through
1991.
They shall also include
the average
annual
total phosphorus content
of the lake water
for each
sampling
location,
and
the
total
rainfall
occurring
at
each
83—43 7
—30—
monitoring
location,
for each year
that these criteria are
monitored.
The annual summaries shall include the annual total
treated
effluent
volumes
and
the
annual
wet
weather,
dry
weather,
and overall daily average treatment flows
for each
of
the
Waukegan,
the North Chicago,
and the Gurnee
treatment plants.
This report shall
also attempt
to analyze and assess the probable
effect of
the NSSD excess flow discharges
on lake phosphorus
water quality.
Finally, NSSD shall submit
a copy of this report
to the Agency, and NSSD or the Agency may use the opportunity of
this April
1,
1992 report,
or any earlier
date,
to bring
to the
Board’s attention
any trends that might
indicate the need for
further Board action.
Submission of this
report shall terminate
NSSD’s continued monitoring imposed by
this Order, unless
otherwise
required by the Agency.
The delayed date
for
submitting
this comprehensive report shall not affect any other
Agency—imposed requirement
for more frequent periodic submission
of monitoring data
to the Agency.
The
Board wants NSSD and other interested persons
to take
special note of
the following:
Nothing
in
this
Opinion
and Order
or
in
the
site—specific
rule
obviates
NSSD
compliance
with
35
Ill.
Adm.
Code 304.105.
ORDER
The
Board
hereby
proposes
the
following
rules
for
First
Notice publication and directs
the Clerk
of
the Board to
file
them with the Office of the Secretary of State.
TITLE
35:
ENVIRONMENTAL PROTECTION
SUBTITLE
C:
WATER POLLUTION
CHAPTER
I:
POLLUTION CONTROL BOARD
PART 304
EFFLUENT STANDARDS
SUBPART
A:
GENERAL EFFLUENT STANDARDS
Section
304.101
Preamble
304.102
Dilution
304.103
Background Concentrations
304.104
Averaging
304.105
Violation of Water Quality Standards
304.106
Offensive Discharges
304.120
Deoxygenating Wastes
304.121
Bacteria
304.122
Nitrogen
(STORET number 00610)
304.123
Phosphorus (STORET number
00665)
304.124
Additional Contaminants
88—438
—31—
pH
Mercury
Delays
in
Upgrading
NPDES Effluent Standards
New
Source
Performance
Standards
(repealed)
SUBPART
B:
SITE
SPECIFIC
RULES
AND
EXCEPTIONS
NOT
OF
GENERAL
APPLICABILITY
Section
304.201
304.202
304.203
304.204
304.205
304.206
304.207
304.208
304.209
304.212
304. 213
304.214
304.219
Calumet
Treatment
Plant
Cyanide
Discharges
Chlor—alkali
Mercury
Discharges
in
St.
Clair
County
Copper Discharges by Olin Corporation
Schoenberger
Creek:
Groundwater
Discharges
John Deere Foundry Disch~rges
Alton Water Company Treatment Plant Discharges
Galesburg
Sanitary
District Deoxygenating Wastes
Discharges
City of Lockport Treatment Plant Discharges
Wood River Station Total Suspended Solids
Discharges
Sanitary District
of
Decatur
Discharges
Union Oil Refinery Ammonia Discharge
Mobil Oil Refinery Ammonia Discharge
North
Shore
Sanitary
District
Phosphorus
Discharges
SUBPART C:
TEMPORARY EFFLUENT STANDARDS
Exception
for
Ammonia
Nitrogen
Water
Quality
Violations
of
the Environmental Protection Act
(Ill.
Rev.
Stat.
1985,
ch.
111—1/2, pars 1013 and 1027)
SOURCE:
Filed with the Secretary of State January
1,
1978;
amended
at
2
Ill.
Reg.
30,
p.
343, effective July 27,
1978;
amended
at
2
Ill.
Reg.
44,
p~
151,
effective November
2,
1978;
amended
at
3
Ill.
Req.
20
p.
95, effective May 17,
1979;
amended
at
3
Ill.
Reg.
25 p.
190,
effective June
21,
1979;
amended
at
4
Ill.
Reg.
20,
p.
53, effective May
7,
1980;
amended
at
6 Ill.
Reg.
563,
effective December
24,
1981;
codified at
6
Ill.
Reg.
7818, amended at
6 Ill. Reg.
11161, effective September
7,
1982;
amended
at
6
Iii. Reg.
13750 effective October
26,
1982;
amended
at
7 Ill.
Reg.
3020, effective March
4,
1983;
amended at
7
Ill.
Reg.
8111,
effective June 23,
1983; amended
at
7
Ill.
Req.
14515,
effective October
14,
1983;
amended
at
7
Ill.
Reg.
14910,
effective November
14,
1983;
amended
at
8
Ill.
Reg.
1600,
effective January 18,
1984;
amended
at
8 Ill.
Reg.
3687,
304.125
304.126
304.140
304.141
304.142
Section
304.301
Appendix A
References
to Previous Rules
AUTHORITY:
Implementing Section
13 and authorized by Section
27
88—4 39
—32—
effective March
14,
1984;
amended
at
8
Ill.
Reg.
8237,
effective
June
8,
1984;
amended
at
9
Ill.
Reg.
1379,
effective January
21,
1985;
amended
at
9
Ill.
Reg.
4510,
effective March
22,
1985;
peremptory amendment
at
10
Ill.
Req.
456, effective December
23,
1985;
amended
at
11
Ill.
Reg.
3117,
effective January
28,
1987;
amended
in R84—l3
at
11
Ill.
Reg.
7291,
effective April
3,
1987;
amended
in ~86—l7(A)
at
11
Ill.
Reg.
14748, effective August
24,
1987;
amended
in R84—l6
at
12
Ill.
Reg.
2445, effective January
15,
1988;
amended
in
R86—3
at
_____
Ill.
Reg.
_________
effective ________________________
Section 304.219
North Shore Sanitary District Phosphorus
Discharg~~
a)
This
Section
applies
to
discharges
from
the
North
Shore
Sanitary
District
excess
flow
discharge
facilities
at
Waukegan
and
North
Chicago
into
Lake
Michigan
b)
The requirements
of Section 304.123(a)
shall
not apply
to the phosphorus content
of
the North Shore Sanitary
District excess
flow discharges
from Waukegan and North
Chicago
into Lake Michigan.
Instead,
the following
requirements
shall
to North Shore Sanitary District
discharges
into Lake Michigan:
1)
The North Shore Sanitary District shall discharge
no effluent into Lake Michigan from its Waukegan
treatment plant until after
that plant has achieved
its maximum peak treatment flow capacity and all
the Waukegan treatment plant excess flow retention
reservoirs
are full
to caPacity
2)
The North Shore Sanitary District shall
discharge
no effluent into Lake Michigan from its North
Chicago treatment plant until
after that plant has
achieved
its maximum peak
treatment flow capacity,
the North Chicago treatment plant excess flow
retention reservoirs
are full
to capacity,
the
maximum practicable
rate
of transfer of
untreated
effluent to Gurnee has been achieved,
the Gurnee
treatment plant has achieved
its maximum peak
treatment flow capacity, and the Gurnee treatment
plant excess flow retention reservoirs are full
to
capacity.
c)
The North Shore Sanitary District shall
increase the
maximum peak treatment flow capacity of
its Waukegan
treatment plant
to
at least
44 million gallons per day
before January
1, 1992
d)
The North Shore Sanitary District shall
increase the
maximum
oeak
treatment flow capacity
of
its Gurnee
88— 440
—33—
treatment plant
to
39 million gallons per day before
January 1, 1989
e)
The North Shore Sanitary District shall increase the
excess flow retention reservoir capacity at its Gurnee
treatment plant to 50 million gallons before January
1,
1991
f)
The North
Shore Sanitary District shall operate
its
Waukegari or North Chicago treatment plant at its maximum
peak treatment flow capacity during any period
in which
less than 90 percent of the retention reservoir capacity
is
available to receive excess flows
at the relevant
treatment plant,
except when such unavailability results
during times of normal
retention basin maintenance; and
~
The North Shore Sanitary District shall
immediate embark
on
‘a program of excess flow and water quality impact
monitoring,
shall
periodically submit the data from such
monitoring
to the Illinois Environmental Protection
Agency (“Agency”),
and shall submit
a comprehensive
study of this data and monitoring for
the period
1987
through 1991 to the Board and the Agency before April
1,
1992.
IT IS SO ORDERED
Chairman J.D. Dumelie concurred.
I, Dorothy M.
Gunn, Clerk of the Illinois Pollution Control
Board,
hereby certify that the above
First Notice, Proposed Rule
Opinion and Order was adopted on the
o?/4*
day
of _______________________,
1988, by
a vote
of
________
lilino
Control Board
88—44 1
