ILLINOIS POLLUTION CONTROL BOARD
November
3,
1988
IN THE MATTER OF:
)
THE PETITION OF THE
)
R86—3
NORTH SHORE SANITARY DISTRICT
)
TO AMEND REGULATIONS
)
ADOPTED RULE.
FINAL ORDER
OPINION AND ORDER OF THE BOARD
(by B.
Forcade):
The North Shore Sanitary District
(hereinafter “NSSD”)
petitioned the Board on December
20, 1985
for
a site—specific
effluent limitation for its discharges into Lake Michigan from
the excess flow facilities at Waukegan and North Chicago.
Specifically,
the petition sought an exception
from 35 Ill. Mm.
Code 304.123(a)
for the discharges of phosphorus
in excess of
1
mg/l
in the effluent from the excess flow facilities located at
the Waukegari 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.
Adm. 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.
93—333
—2—
The Board adopted
for first notice an amended version of
the
requested site—specific rule by its Opinion and Order of April
21, 1988.
This new Section 304.219, 35
Ill. P~dm.Code 304.219
(1988), was published in the Illinois Register for public
comment.
12 Ill. Reg.
7960
(May
6, 1988).
The 45—day first
notice comment period ended on June 21, 1988.
The agency
submitted its comments on August 16,
1988.
Other, non—
substantive comments, were received from NSSD on August
12 and
17,
1988.
These non—substantive comments did not relate
to the
merits
or substance of the proposed
rules.
The Board adopted this rule for second notice on September
8,
1988, with minor, non—substantive revisions made in response
to the public comments.
The commenters generally agreed
that the
requested
rule was appropriate, and neither
of the commenters
requested any substantive alteration.
However,
their comments
warranted some clarification of the April
21,
1988 Opinion and
Order, and some minor revision of the language of the rule was
warranted.
The minor modifications did not affect the scope or
substance of
the proposed
rule.
These amendments are outlined
in
the discussion of the first notice revisions.
The second notice comment period ended October
31,
1988.
JCAR reviewed the rule at its October
13,
1988 meeting and served
the Board with
its Certification of No Objections with its letter
of October 13,
1988.
The amendments adopted as
a result of JCAR
discussions are minor and non—substantive,
and only one affects
the language of the proposed
rule.
These final amendments are
outlined
in the discussion of the second notice revisions.
The following discussion is organized into three major
discussions:
Original Proposed Rule,
First Notice Revisions,
and
Second Notice Revisions.
These discussions are followed by the
text of the final rule as adopted this day.
ORIGINAL PROPOSED RULE
The Board reviewed the record
in its April
21,
1988 Opinion
and Order:
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 Waukegari 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.
93—334
—3—
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.
Ill.
Rev. Stat.
ch.
42, par. 276.99—298a
(1987.).
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 MCD
in 1978—79.
The plant can provide full
treatment
to
a peak flow of about
30 MCD during wet weather and
its average wet weather flow was 26.0 MGD during this period.
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 presedimeritation basins having
a
combined capacity of
1.38 million gallons
(“MG”).
Overflows from
93—335
—4—
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.
Ex.
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.
Ex.
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 MC 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.
Ex.
4,
pp.
4—8;
Ex.
5, App.;
Ex.
7.
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 ~pril, 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
93—336
—5—
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/i
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
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:
93—337
—6—
Nurrbers
aixi
Volumes
of Waukegan
Overflow
Disdiarges
by
Event
Size
By
Nurrber
of
Events
~y
Category
Volume
Size
of
Event
Nuither
Percent
Cum
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/i, with an overall average over the
nearly five years
of 1.3 mg/i.
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/i
as
P.
A summary tabulation of the 197
detailed data,
categorized by effluent phosphorus content and the
associated percentage of discharges within each category,
f01lows:
93 —3 3S
—7—
Nurrber of Event—Days Disdiarging Specified
Phosphorus
In Effluent
Effluent Phosphorus Content (mg/i as 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
lB
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
‘tOTAL
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/i.
Ex.
4,
p.
4—8;
Ex.
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,
Ex.
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 10 mg/l 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
MCD.
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
93—339
—8—
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 MGD 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—i;
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:
93—340
—9—
Corr~arisonof
NSSD
and
Estimated
Phosphorus
Reductions
by
Method
of
Reduction
for
Waukegan
Phosphorus
Disdiarges
Phosphorus
Reduction
Method
NSSD
1979—83
Estimates
1980—87
Estimates
Existing
Facilities
2,900
pounds
3,950
pounds
Chemical
Renoval
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.
93—34 1
—10—
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.
Ex.
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 MGD
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.
Cx.
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, Ex.
4,
pp.
4—9; Ex.
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
MG discharged
to the lake
in
50 event—days.
Cx.
4,
pp. 4—10.
93—342
—11—
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
Average*
1979
418 MG
50
3.0 mg/i as P
1980
9~3**
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/i 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:
93—343
—12—
Nunbers
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
1 MG to
2 MG
2 MG to
4 MG
4 MG to
6 MG
6
MC
to
8
MC
8 MG to 10 MG
Greater
10
MG
Totals
By
Nunber
of
Events
Nuither
Percent
Cum
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
—
B~yCategory
Volume
MG
Percent
Cum.
1.66
0.3
0.3
5.18
1.0
1.3
17.5
.
3.2
4.5
45.82
8.5
13.0
110.08
20.5
33.5
125.90
23.4
56.9
131.24
24.4
81.3
43.96
8.2
89.5
56.58
10.5
100.0
537.57
100.0
—
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/i,
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/i as P.
A summary
tabulation of
these data,
categorized by effluent phosphorus
content,
and
the
associated
percentage
of
discharges
within
each
Category,
follows:
93— 344
—13—
Nuther
of
Event-Days
Discharging
Specified
Phosphorus
in
Effluent
Effluent Phosphorus
Content
(mg/i as P)
Year
1.0
1.0—2.0
2.0—3.0
3.0—4.0
4.0—5.0
5.0
Total
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
T~~AL
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/i 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.
Ex.
4,
pp.
4—9;
Cx.
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/l
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
93—34 5
—14—
chloride
chemical
removal
system
under
the
current
operational
scheme.
This is about $20 per pound
of phosphorus
that the
system would
remove.
Cx.
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.
Cx.
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 MCD by December,
1987;
to 19.6
MCD by December,
1988.
R.
67—68
&
83.
The Gurnee STP currently receives an average of
12.4 MCD for treatment.
R.
67.
When
fully
expanded,
the
plant
will accept
a peak flow of 39.2 MCD.
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
carl
operate
its
North
Chicago
sewage
transfer
pump
to
Gurnee
at its full capacity of
25.5
MCD,
as opposed
to the current
maximum
of
about
12
MCD,
R.
80—81,
an additional
13.5
MCD
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
wou~dmean
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:
9 3—34 6
—15—
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
Renoval 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
chiorophyl
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 waukegan 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
93—347
—16—
standard
for
phosphorus
in
the
lake
is
0.007
mg/i
(as
p)•*
35
Ill.
Adm.
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 Corn.
(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,
Ex.
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,
Cx.
8,
pp.
27-30:
Phosphorus
Source
Phosphorus
Contrilxition
County
L Michigan
Storm..iater
13,400
pounds
6.3
Q.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.
Cx.
8,
pp.
19
&
37.
*
See infra footnote on page
17.
93— 348
—17—
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 Waukegan 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.
Ex.
4,
p.
4—1; Ex.
9,
p.
16;
Cx.
10,
p.
19;
Cx.
11,
p.
19.
Only six of
these sampling
stations were near the Lake County shoreline, however,
and only
three were near
the NSSD overflow outfails.
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
0.02 mg/l or lower are considered herein within the standard, and
any of 0.03
rng/l
or higher are deemed
to have “clearly violated”
the standard.*
The
detailed
water
quality
survey
data
for
1981
through
1985,
Ex.
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. Adm. Code 302.504.
The relevant sampling points
and their approximate
locations were the following:
5N
1 mile offshore
frc*n
Great Lakes NTC
6N
1 mile offshore from
midway
between Great Lakes NTC and
Waukegan Harbor
7W
1 mile
offshore
from Wa~keganHarbor
8N
4 miles offshore from Lake Forest
9W
5 miles
offshore
from Highland
Park
iON
3
miles
offshore
from Glencoe
The sampling points SN,
GN,
and 7W 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
WSSD samples
(31)
clearly violated the standard.
The other
three off—shore sampling points away from NSSD outfalls c~early
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 WSSD 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.
9 3—349
—18—
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/i
as
pQ4)*
Probability
0b5.
“Clear
(N.to
S.)
Mean
L~er 95
C.L.
Upper
95
C.L.
of Violation
Violations”
7W
0.025
0.017
0.033
57
30
6N
0.022
0.016
0.027
51
33
5N
0.021
0.016
0.026
51
30
Avg.
Near
0.023
0.019
0.026
54
31
SN
0.022
0.015
0.028
51
24
9W
0.021
0.016
0.027
51
24
iON
0.019
0.015
0.023
44
27
Avg. Away
0.021
0.017
0.024
49
25
Avg. All
0.022
0.019
0.024
52
28
*De~tes that
the
conversion
from phosphate
to phosphorus in~olvesnultiplication
1~j0.3261.
To
convert
from
phosphorus
to
phosphate
multiply
by
3.066.
The
“probability
of
violation’1
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 MC
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:
93—350
—19—
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
0.0021
0.0028
0.0043
0.0064
*00106
2
0.0043
0.0055
*00085
*00128
*0.0213
5
*00106
*00138
*00213
*0.0319
*0.0532
10
*00213
*0.0277
*00426
*00638
*01064
*Denotes
that
the
effluent
contribution
alone
violates
the
water
quality
standard
of
0.007
mg/i
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
(mg/i
as
P)
in
One
Mile
Zone
Discharge
Phosphorus
Content
of
Effluent
(mg/l
as
P)
Volume
(MG)
1.0
1.3
2.0
3.0
5.0
1
0.0002
0.0002
0.0003
0.0005
0.0008
2
0.0003
0.0004
0.0006
0.0009
0.0015
5
0.0008
0.0010
0.0015
0.0023
0.0038
10
0.0015
0.0020
0.0031
0.0046
*00076
20
0.0031
0.0040
0.0061
*00092
*00153
*Denotes that the effluent contribution alone violates
the water
quality standard
of 0.007 mg/i 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
Cx.
9;
Cx.
10;
Cx.
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/i as P
during this period, with a maximum of 2.70 mg/i.
The mean Worth
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
1’,
and the maximum was 9.08 mg/i.
The NSSD consulting engineer concluded that
the impact of
NSSD phosphorus discharges on the lake was unknown,
but that it
warranted further monitoring and study.
The consulting engineer
recommended that NSSD should develop and implement
a program of
93—351
—20—
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 1980—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
biomass,
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 concornmitantly increased algal
bioom.
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
ri~t in
a
form
that
can
relate
to
biomass
and
phosphorus.
See
Ex.
9,
pp.
49—58;
Cx.
10,
pp.
55—63;
Cx.
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.
WSSD 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:
Waikegan:
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:
93—352
—21—
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 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
riot 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 plant.*
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 Waukegari 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.
Ex.
5,
p.
3—3.
Illinois Beach State
Park
is
over
a
mile
north
of
the Waukegan outfall.
Cx.
1.
The
Foss
Park
sampling
site
is
about
1,800
feet south of
the North
Chicago CSO outfall.
Ex.
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
possible after events during the non—swimming months.
The Agency
*
See supra footnote on page
1.
93—353
—22—
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,
BOD, TSS, and volatile
solids testing of sediment samples,
but it does not recommend a
sampling frequency.
II.
Discussion
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
limi-
tation despite good engineering practice;
3.
Merely
focusing
on
a
numerical
effluent
limitation
can
ease
the
burden
of per-
formance 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 phos-
phorus
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;
5.
Statistically,
the
average
annual
phos-
phorus
content
of
the
North
Chicago
effluents
significantly
decreased
since
about
1983,
and
showed
greater
varia—
93—354
—23—
bility
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 and
the
highest
number
of
events
at Wauke—
gan.
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.
The
record
does
not
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/l as
P for North Chicago;
9.
The greatest
reductions
in overall
total
phosphorus
loading
to
the
lake
would
result
from
diversion
of
overflow
dis-
charges
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 dis-
charged
by
at
least
a
similar
amount.
Similar elimination
of the first
13 MG of
all
North
Chicago
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
93—355
—24—
of
about
12 MCD
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
19.8
MGD
and
peak
capacity
of
about
30
MGD
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 pos-
sible
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
Waukegan
and
North
Chicago
to
construct
additional
retention
capacity
at
either
facility;
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
~aukegan
and
expansions
at
Gurnee;
93—356
—25—
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 mesotrophic
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.
The record does not permit the conclusion
that
either
the Waukegan or North Chicago
overflow
discharges
directly
and
significantly
contribute
to
or
cause
water
quality
violations
or
cause
an
adverse impact on the
lake;
18.
The
record
does
not permit
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
mesotrophic 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 outfails
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:
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?;
93—3 57
—26—
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
record
does
not 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
93—358
—27—
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/i maximum
1.3 mg/i annual average
Worth Chicago STP,
4.0 mg/i maximum
3.0 mg/i annual average
These
limitations would adequately accommodate the current
effluent qualities of both plants without permitting effluent
quality degradation.
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
modi f i cat ions:
1.
It would
seek additional
data collection
for
possible
future
regulatory
action,
should
further
study
reveal
that
NSSD
93—359
—28—
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 and December
1,
to
be
collected at
a
single
selected
site at
the following locations:
Illinois Beach State Park,
Waukegan
North
Beach,
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;
93—360
—29—
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
at
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
—
Total
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:
Waukegart 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.
93—361
—30—
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
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 arid 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 ~gency 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
93—362
—31—
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.
FIRST NOTICE REVISIONS
The Board responded to the second notice public comments by
its September
8,
1988 Opinion and Order:
Monitoring
(Section 304.219(g))
NSSD cites the fact that weather may
impede sampling and
testing from October through April.
The Agency recognizes this,
but cites
the fact that overflow events are most likely
in the
late Fall and early Spring.
The Board recognizes that safety
concerns and vessel unavailability may occasionally preclude
sampling,
but
believes
sampling
should occur during
these months
when
possible.
This
clarification
of
the Opinion and Order
warrants
no
change
in
the
language
of
the
rule.
The Agency states that its
initial request for
beach
sediment testing intended “concurrent monitoring” with the
offshore monitoring
for background data,
but the Agency does not
now request
it or justify
it.
The Agency also comments that the
monitoring requirement
is unclear, but the Board believes
that
explicit definition of the terms used
in the rule is given in the
accompanying Opinion and Order.
One necessary clarification of
that Opinion and Order
is
that rainfall monitoring at Gurriee was
intended,
and NSSD should
submit this data
to the Agency.
See
Opinion and Order of April 21,
1988 at 29.
Because this is
a
site—specific rule,
the definition added by the Opinion and Order
clarifies the
rule.
Therefore,
the Board will not revise
the
rule or accompanying Opinion and Order.
Plant Design and Operation
(Sections 304.2l9(b)—(f))
NSSD comments that plant operational constraints will not
always permit operation up to the peak treatment capacity,
and
requests deletion of the word,
“peak,” where
it appears in
subsections b and
f.
The Agency agrees.
The Board deletes the
word.
At NSSD’s suggestion,
the Board aiso revises the phrase,
“times of normal
retention basin maintenance,” to the phrase,
“times of normal treatment plant and/or retention basin
maintenance,”
in subsection
f.
The Agency requests that the Board impose interim project
completion dates
in Section 304.219(c).
The Board does not
believe this
is appropriate
to this site—specific rule.
NSSD
must accomplish the required facilities expansions before the
given date,
and the Agency
is free to monitor progress without
the requested interim dates.
The requirement for the completion
of
this project before
a date certain satisfies the Agency’s
93—363
—32—
primary concerns, and the Agency agrees
that the reduction of
discharge volumes is the desired objective.
Error Corrections
(Section 304.219(b)
&
(g))
The Board corrects two minor errors
in the proposed
language.
The Board corrects
that portion of subsection b which
reads “requirements shall
to North Shore Sanitary District”
to
read “requirements shall
apply to North Shore Sanitary District”
by appropriately inserting “apply.”
The Board corrects that
portion of subsection g which
reads “shall immediate embark”
to
read “shall immediately embark” by changing the adjective,
“immediate,” to the adverb,
“immediately.”
Summary of Revisions
Subsection
b:
add the word,
“apply,” as the sixth word
of
the second sentence;
and
delete the word,
“peak,” wherever
it
appears
in this subsection.
Subsection
f:
delete the word,
“peak,” wherever
it appears
in this subsection;
and add the words,
“treatment plant and/or,”
as the fifty—sixth through fifty—ninth words
of the subsection.
Subsection
g:
replace the word,
“immediate,” with the word,
“immediately,” as the seventh word of the subsection.
SECOND NOTICE REVISIONS
By its September
21,
1988 letter, JCAR addressed various
questions to the Board that embodied their concerns over the
second notice proposed rule.
After discussions with JCAR staff,
Board staff addressed those questions by an October
3,
1988
letter
and recommended various revisions to the Board.
The
recommended revisions were minor:
one
to the table of contents,
two
to the “Authority” section, one to the “Source” section,
and
one
to the text of the proposed rule at Section 304.219(g).
The
Board staff—recommended revision to the text of Section
304.219(g) was minor,
and it was intended to add clarity
to the
Board’s intent as expressed
in the proposed
rule adopted for
second notice publication.
The Board now adopts the revisions
recommended
by
its
staff.
The revisions adopted as
a result of JCAR dialogue and
resulting Board staff recommendations are topically summarized
below.
1.
Table
of Contents:
The title
of Section 304.201
shall appear
as follows:
304.201
Wastewater Treatment Plant Discharges of
the
Metropolitan Sanitary District of Greater
Chicago
93— 364
—33—
The titles of intervening
new sections 304.210,
304.215,
and
304.216 are added
in their respective proper positions.
2.
Statutory Authority:
The statutory
“Authority” section is
amended
to reflect the 1987 version of the Illinois Revised
Statutes,
and
the section concludes with
a period.
3.
Source Notes:
The regulatory “Source” notes section is
amended
to reflect the intervening adoption of new rules, by
inserting after “January 15, 1988” the following
text:
amended
in R83—23 at 12 Ill. Reg.
8658, effective May
10,
1988; amended
in R87—27 at 12 Ill.
Reg.
9905,
effective May 27,
1988;
amended
in R82—7
at 12
Ill. Reg.
10712, effectivew June
9,
1988;
amended
in R85—29 at
12
Ill.
Reg.
12064, effective July 12,
1988;
amended
in
R87—22 at 12 Ill. Reg.
13966, effective August 23,
1988;
4.
Text
of Section 304.219(g):
The text of Section 304.219
is
amended by adding
the following text between the sixth and
seventh words
of
the
proposed
rule
as
published
for
second
notice:
as required pursuant to Section 309.141,
Text of Final Rule
The text of the final
rule as adopted this date
is indicated
in the following Order.
ORDER
The Board hereby adopts the following rule and directs the
Clerk
of the Board to file it 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
9 3—365
—34—
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
304.210
304 .212
304.213
304.214
304.215
304.216
304.219
Wastewater Treatment Plant Discharges of the
Metropolitan Sanitary District
of Greater Chicago
Chior—alkali Mercury Discharges
in St. Clair County
Copper
Discharges
by
Olin
Corporation
Schoenberger Creek: Groundwater Discharges
John Deere Foundry Discharges
Alton Water Company Treatment Plant Discharges
Galesburg Sanitary District Deoxygenating Wastes
Discharges
City of Lockport Treatment Plant Discharges
Wood River Station Totai Suspended Solids
Discharges
Alton Wastewater Treatment Plant Discharges
Sanitary District
of Decatur Discharges
Union Oil Refinery Ammonia Discharge
Mobil Oil Refinery Ammonia Discharge
City of Tuscola Wastewater Treatment Facility
Discharges
Newton Station Suspended Solids Discharges
North Shore Sanitary District Phosphorus Discharges
SUBPART C:
TEMPORARY
EFFLUENT STANDARDS
Section
304.301
Appendix A
Exception for Ammonia Nitrogen Water Quality
Violations
References
to Previous Rules
AUTHORITY:
Implementing Section 13 and authorized by Section 27
of the Environmental Protection Act
(Ill. Rev.
Stat.
1987,
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. Reg.
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 Ill.
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. Reg.
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,
effective March 14, 1984;
amended
at
8
Ill.
Reg.
8237,
effective
93—366
—35—
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. Reg.
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 R86—l7(A)
at 11
Ill. Reg.
14748, effective August 24,
1987; amended
in R84—16 at 12 Ill.
Reg.
2445, effective January
15,
1988;
amended in R83—23 at 12
Ill. Reg.
8658, effective May
10,
1988; amended
in R87—27 at 12
Ill. Reg.
9905,
effective May
27,
1988; amended
in R82—7 at
12
Ill.
Reg.
10712, effective June
9,
1988; amended
in R85—29 at 12 Ill.
Reg.
12064, effective July
12,
1988; amended
in R87—22 at 12 Ill. Reg.
13966,
effective
August 23,
1988; amended
in R86—3 at
_____
Ill. Reg.
_________
effective ________________________
Section 304.219
North Shore Sanitary District Phosphorus
Discharges
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
apply
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 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 treatment flow capacity,
the
North Chicago treatment plant excess flow retention
reservoirs are full
to capacity,
the maximum rate
of transfer of untreated effluent to Gurnee has
been achieved,
the Gurnee treatment plant has
achieved its maximum 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
Waukegari
treatment plant to at least
44 million gallons per day
before January
1, 1992
93—367
—36—
d)
The North Shore Sanitary District shall increase the
maximum peak treatment flow capacity of its Gurnee
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
Waukegan or North Chicago treatment plant
at
its maximum
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 treatment plant and/or retention
basin maintenance;
and
~j
The North Shore Sanitary District shall,
as required
pursuant
to
Section
309.141,
immediately
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
I, Dorothy M. Gunn,
Clerk
of the
Illinois
Pollution Control
Board, hereby certify that the above Opinion and Order was
adopted on the
cIAI~
day
of
‘~#2-~—t&z&’
,
1988,
by a
vote
of
~_-o
A
Dorothy M.,~unn,Clerk
Illinois tt6llution Control Board
93—368
