ILLINOIS POLLUTION CONTROL BOARD
January
7,
1988
IN THE MATTER OF:
PROPOSAL OF MOBIL OIL CORPORATION
TO AMEND THE WATER POLLUTION
)
R84-16
REGULATIONS
ADOPTED RULE.
FINAL ORDER.
OPINION AND ORDER OF THE BOARD
(by
J.
Marlin):
This matter comes before the Board upon the May 1,
1984
filing
of
a proposal by Mobil Oil Corporation
(Mobil)
requesting
site—specific relief from the ammonia nitrogen effluent standard
(35
Ill. Adm. Code 304.122(b)).
Relief
is also requested
from
the requirement that no effluent shall cause
a violation of
a
water quality standard
(Section 304.105)
as
it
concerns the
general use ammonia nitrogen water quality standard
(WOS)
(Section 302.212), the secondary ammonia nitrogen WQS
(Section
302.407), the general use dissolved oxygen
(DO) WQS
(Section
302.206)
and the secondary DO WQS
(Section 302.405).
Mobil
discharges
into the Des Plaines River.
Hearing was held
in Joliet, Will County, on July 26, 1984.
On October 30 and December
13,
1984, Mobil filed responses to
the
written inquiries of the Illinois Department of Energy and
Natural Resources (DENR).
The DENR concluded that an economic
impact study was unnecessary and filed its negative declaration
on February 22,
1985.
The Economic Technical Advisory Committee
agreed with this finding, filing its concurrence on March
12,
1985.
The last brief was filed on June
4,
1985.
The Board by
Interim Order dated September
5,
1985, requested that the
participants address the question of whether the Board has
authority to grant site—specific relief
from
35
Ill. Mm. Code
304.105.
On February
4,
1986,
the Agency moved
to file United
States
Environmental Protection Agency
(USEPA) comments, and on
February
7,
1986,
Mobil moved
to file its response to USEPA
comments.
Mobil’s response contained a proposal
to amend
the
language of the proposed rule.
Both motions were granted by the
Hearing Officer on February 24, 1986.
The Agency on March
20
filed
its response to Mobil’s response and modified proposal.
On
April
10,
1986, Mobil moved
for leave to file its reply to the
Agency’s response to the modified proposal.
That motion was
granted.
On July 7,
1986,
Mobil
filed
a motion for leave to file
Comment
in Opposition
to Applicability of Central
Illinois
Public
Service Company
v.
PCB to this cause.
In the Agency’s response,
filed on July 17,
1986,
the Agency did not object to Mobil’s
motion.
Mobil’s motion was granted.
85—103
2
On February
5,
1987,
the Board adopted
a proposed rule for
First Notice.
This proposed rule was published in the Illinois
Register on March 13,
1987.
11
111.
Reg.
4210.
On April
27,
1987,
Mobil
filed comments cited herein as “P.C.
#1”.
On June
5,
1987,
Mobil
filed
a supplement to its comments.
The Agency filed
its comments, cited herein as
“P.C.
#2”, on June
7, 1987.
Although these latter two filings were filed subsequent
to the
closing of
the 45—day comment period, the Board accepted and
fully considered these late filings.
The Board adopted the proposed rule
for Second Notice on
October
29,
1987.
In that version of the rule,
the Board deleted
the annual average effluent limitation, which was
a part of the
First Notice proposal, but added
a provision stating
that the
effect
of. the rule terminates on December 31,
1993.
On December
22,
1987,
the Joint Committee on Administrative Rules
(JCAR)
filed
its Certification of No Objection to Proposed Rulemaking
for this matter.
Today the Board will adopt,
as final,
substantively the same version of the rule that it adopted for
Second Notice.
Mobil
is currently operating under
a variance from
3 mg/I
ammonia nitrogen effluent standard of 35
111. Adm. Code
304.122(b)
until July 1,
1988 or until
final action
is taken
in
this matter, whichever occurs first.
Under this variance, the
ammonia nitrogen concentration in Mobil’s discharge must not
exceed
a monthly average concentration of 25 mg/l and
a daily
maximum of
35 mg/l.
Mobil Oil Company v.
Illinois Environmental
Protection Agency, PCB 86—45,
slip Opinion and Order
at
4
(August
14,
1986).
Mobil has been granted five previous variances from
the ammonia nitrogen standard:
PCB 77—22,
PCB 78—97, PCB 80—54,
PCB 82—36
and PCB 84—37.
Mobil has incorporated by reference the
proceedings of the five variances in this regulatory proceeding.
(R.
114).
Mobil owns and operates
a conventional
fuels petroleum
refinery with
a rated capacity of 180,000 barrels per day located
in Joliet,
in Will County.
The refinery discharges 2.74 million
gallons of effluent per day.
Stormwater, noncontact cooling
water
and process water are discharged from the facility into the
Des Plaines River.
The process water
and contaminated surface
runoff
(1600
gpm)
are treated
in Mobil’s wastewater treatment
plant
(WWTP) which consists of an API separator,
a dissolved air
flotation unit, an equilization basin
for primary treatment and
a
conventional activated
sludge facility for secondary treatment.
Treated effluent from the final clarifier
is routed through
a
4.98 million gallon guard basin where
it
is retained
for
approximately 51 hours and then aerated
in the final
aeration
cone prior
to release
to the Des Plaines River.
The effluent
meets all discharge standards other than ammonia nitrogen.
Mobil
Oil Company, PCB 86—45
at 1—2.
85—104
3
Mobil
is requesting
that its effluent limits
for ammonia
nitrogen be set at
25 mg/l for
a monthly average and 40 mg/l
for
a daily maximum.
(Pet. Brief,
p.
3).
In the past
13 years, Mobil has expended considerable time
and effort
in its attempt
to reach ultimate compliance with the
ammonia standards.
The total cost of ammonia related capital
expenditures
is
in excess of $2.1 million.
The average annual
operating cost for ammonia reduction projects during the last
five years has been $1,801,000, including amortization of capital
investments.
Equalization system improvements and continuous
dissolved oxygen monitoring
in the aeration basins cost an
additional $64,000 between 1982 and 1985.
Projects have included
the purchase and installation of
a nitrification pilot plant,
nitrification inhibition studies, mutant bacteria trials,
alkalinity addition and temperature control
in the aeration
basins.
Since
1973,
these efforts have reduced Mobil’s
discharged ammonia concentration by 96 percent.
Mobil Oil
Company,
PCB 86—45 at
2.
Mobil investigated
six alternative nitrification
technologies.
Three biological systems (activated sludge,
trickling filter
and rotating biological contactor) were rejected
because of their inability to consistently achieve the ammonia
nitrogen effluent standard
of
3 mg/l
(R.
97—8,
See Pet.
Exh.
2,
p.
59,
60).
Three chemical processes were also addressed.
Breakpoint chlorination and
ion exchange processes would
consistently meet the
3 mg/l standard
(R. 94—5).
However,
breakpoint chlorination was not recommended because of the
formation and release of toxic chlorinated byproducts
(R.
94).
The
ion
exchange
process
would
entail
a
7—8
million
dollar
capital
cost
with
a
$450,000
annual
operating
cost,
plus
an
added
cost for activated carbon treatment
if organic fouling occurred
(R.
95).
The third chemical process, ammonia stripping, would
not enable Mobil
to reduce
its effluent concentration enough
to
achieve the
3 mg/l standard.
In addition,
it has relatively high
capital and operating costs as well as potential operational
problems.
(R.
96).
After assessing the available control
alternatives,
an expert witness for Mobil concluded that absolute
compliance with the 3 mg/l standard could only be achieved by the
ion exchange process.
He stated that “ijn
the absence of a
beneficial influence on receiving water quality,
it
is difficult
to recommend the expenditure of several million dollars
to
achieve further reduction
in effluent ammonia at the Joliet
refinery.”
(R.
103).
Environmental Impact
Water quality standards for ammonia nitrogen and dissolved
oxygen are being exceeded
in the Des Plaines River
at the point
of Mobil’s discharge, river mile 278.
(R.
157—8).
Mobil asserts,
and the Agency agrees,
that the condition of the river
is
primarily due
to the discharges of three Metropolitan Sanitary
85—105
4
District of Greater Chicago
(MSDGC)
sewage treatment plants
located upstream of Mobil.
(Pet. Brief,
p.
6—7; Ag. Brief,
p.
3).
Based on an annual average,
calculated from data taken frdm
July,
1982 through December 31,
1983, Mobil’s discharge
constitutes 0.3 percent of the river’s
total point source loading
of ammonia nitrogen.
(R.
139).
Th MSDGC sewage treatment plants
discharges make up 96 percent of the ammonia nitrogen loading.
(Pet. Exh.
#7,
p.
8).
The Agency concurs with Mobil that Mobil’s current
discharges of ammonia nitrogen have “no significant environmental
impact.”
The Agency states that “continued discharges by Mobil
at its present rate and concentration will have no discernible
effect upon the biota
in the lower Des Plaines and upper
Illinois
Rivers.”
(Ag. Brief,
p.
3).
In addition, the nearest actual
or proposed public water
supply downstream of Mobil’s outfall
is the City of Peoria which
is 110
river miles away.
Because of the distance and the
relative amount of the discharge,
a witness
for Mobil stated
that
the ammonia nitrogen added by Mobil would have “appreciable time
for degradation” by the time
it reaches Peoria.
(R.
182).
Economic Impact
An expert witness for Mobil
stated that
if the lower Des
Plaines and upper Illinois rivers improved greatly in quality
such that
it would become a combined sport and commercial
fishery,
its value would be $51,633 per mile per year.
(R.
187).
If Mobil discharged
3 MGD at
40 mg/l into the river during
a seven—day,
ten—year low flow of 1186 MGD,
the river’s
concentration of ammonia nitrogen would rise by 0.101 mg/l near
the discharge point.
(R.
145—6).
The river would flow
approximately 1.85 miles before returning
to the original ammonia
nitrogen concentration.
(R.
187—88).
If
it
is assumed that a
0.101
rng/l
increase
in ammonia nitrogen would completely destroy
the value of the river’s potential
in being
a sport and
commercial fishery (within that 1.85 mile stretch), the impact
would equate to
a loss of $95,521 per year.
When figuring
Mobil’s relative contribution to an overall 1.6 mg/l
river
concentration, the monetary loss directly attributable
to Mobil
would
be $6,448 per year.
(R.
188)
It was estimated that
if
Mobil
is granted relief,
it would save,
at the minimum, $420,000
per year.
Based upon
these assumptions, the ratio of Mobil’s
savings to society’s cost would be
65 to
1.
(R.
189—90).
It
is
Mobil’s position that a treatment plant expansion, required
to
achieve complIance with the existing standard
is not economically
justified.
(Pet. Brief,
p.
10).
The Agency concurs with Mobil
that “the ratio of likely cost expansion to likely beneficial
impact would be extremely high, and thus economically
unjustified.”
(Ag. Brief,
p. 4).
85—106
5
The Department of Energy & Natural Resources (DENR)
concluded that the “cost of making
a formal study is economically
unreasonable
in relation
to the value of the study to the Board
in determining the adverse economic impacts of the regulation.”
(DENR Negative Declaration, p.
2).
Consequently,
it issued
a
negative declaration
in this matter.
Ammonia Nitrogen Limitations
Mobil
requested that the Board
set limitations of a
25 mg/l
monthly average and a 40 mg/l daily maximum.
These limitations
were determined by evaluating
the historical performance data of
the WWTP.
According to Mobil,
these limits are necessary to
account for fluctuations
in the effluent concentrations.
Studies
indicate that the WWTP consistently removes a 17 mg/l increment
from the WWTP influent.
Consequently, Mobil concludes that the
effluent fluctuations are due
to higher crude nitrogen and
production levels.
Due
to these variations, Mobil states that
the requested limitations are necessary to “insure consistent
compliance.”
(Pet.
Reply, p.
6).
Pursuant to a Hearing Officer Order dated August
13,
1985
in
this proceeding
and the variance conditions of PCB 86—45,
Mobil
has submitted bi—monthly reports which cover effluent data from
January,
1983 to August,
1987.
The data from these bi—monthly
reports can be summarized
as follows:
AMMONIA NITROGEN CONCENTRATIONS
(MG/L)
Yearly Avg. of
Highest Monthly
Highest Daily
Year
the Monthly Avg’s.
Avg.
Maximum
1983
4.35
15
27
1984
2.58
8
19
1985
3.33
16
25
1986
4.00
11
32
19871
1.89
(8 month
avg.)
3.5
13.1
The Board recognizes that
in 1973 Mobil’s monthly discharge
averaged 77 mg/I
and that
in 1979 and 1980,
it averaged 13 and 17
mg/l respectively.
Mobil Oil Company, PCB 86—45 at
2.
However,
1
The values for 1987 are derived from data concerning Mobil’s
discharges during the period from January,
1987
to August,
1987.
This data was filed by Mobil
on September 17
as
a part of
its Bi—monthly Progress Report.
85—107
6
data from the past
4 2/3 years indicates that Mobil’s actual
performance
level,
when
calculating
an
annual
average,
of
the
monthly
figures,
is
quite
close
to the
3
mg/l
standard.
The Board finds that
if Mobil
is granted relief, the
resulting environmental and economic impact would be minimal.
Considering the available alternatives
for Mobil, compliance with
the
3 mg/l standard, although technically feasible, would
be
economically unreasonable given Mobil’s current performance
levels.
Consequently,
the Board will grant Mobil
relief from
Section 304.122(b).
The Agency is concerned that
if the Board grants Mobil
the
limits that it is requesting, Mobil may relax
its present control
methods thereby increasing
the ammonia nitrogen concentration in
its discharge.
The Agency proposed
a 10 mg/l monthly average,
a
30 mg/l daily maximum, and
a
5 mg/l annual average.
The Board
shares the Agency’s concern
in light of the fact that limits
requested by Mobil are considerably higher
(sometimes by a factor
of two)
than its actual discharge.
As
a result,
the Board proposed for First Notice that
Mobil’s discharge not exceed
the
following limitations:
monthly
average,
20 mg/l;
daily composite,
35 mg/l; and and yearly
average,
8 mg/l.
The daily composite limit was set to allow
Mobil
the day to day fluctuations of effluent concentrations that
it periodically experiences.
The monthly average limit was set
to account for the impact that these daily fluctuations have upon
a monthly average calculation.
The yearly average of
8 mg/l was
set to allow for considerable deviation from current performance
due
to anticipated problems and varying feedstocks without
allowing Mobil
to significantly decrease
its control efforts.
Even after recognizing the fact that Mobil experiences periodic
losses of nitrification, the Board viewed Mobil’s current
performance levels as falling within the proposed effluent
limits.
However,
in
its
first Notice comments,
Mobil disagrees.
Mobil
first claims that the Board
is without authority to
impose
an annual average.
Secondly, Mobil asserts that the
annual average imposed by the Board
is unsupported by the
record.
The Board will address this second argument first.
Mobil claims that the Board imposed the annual average only
because the Board was concerned that
if Mobil was granted relief
it might
relax
its treatment efforts in the future.
(P.C.
#1,
p.
5).
Mobil
is partially correct.
The Board fashioned
relief with
a monthly average, daily maximum,
and yearly average
so as to
keep Mobil’s discharge as close
as possible to
the
3 mg/l
value.
Also,
the combination of these
three limits would allow
for
some variability
in
the discharge due
to periodic losses of
nitrification.
The
Board
viewed
the
annual
average
limit
as
providing added
incentive for Mobil
to work to keep its discharge
concentrations low.
As stated above,
the ammonia concentrations
85—108
7
of Mobil’s discharges,
for the years 1983 through August
1987,
were at levels significantly lower than the 35/40
level, which
Mobil has requested.
It naturally follows, then,
that
if Mobil was granted relief
as
it has requested,
it could discharge effluents with
significantly greater concentrations of ammonia than
it has
discharged during
the past
4 2/3 years.
By taking this position,
the Board
is not suggesting that Mobil would deliberately seek to
decrease
its ammonia control efforts, but rather without the
annual average, there would
be no legal incentive for Mobil
to
keep the discharge at levels
it has attained since
1983.
In support of its position, Mobil points
to
a statement made
at hearing by James Patterson,
Ph.D.
In its comment, Mobil
quotes Patterson:
As
I
testified,
at
the
limits
that
I
mentioned,
35
daily
and 25
monthly,
there
is
a
five
percent
probability
that
they
would
violate
those
standards based
upon the
1982—
83 data.
They would have
to actually improve
their
performance
in
order
to
not
violate
those standards.
(emphasis added)
(R.
104—5).
It is important to note that this statement was made on July
26,
1984 and was based solely on the effluent data of 1982 and
1983.
Mobil
seems to ignore
the performance levels attained by
Mobil
since
1983.
Mobil
also quotes the Board’s Opinion from PCB 86—45,
a
variance proceeding.
Mobil has made admirable progress
in reducing
its
nitrogen
discharge,
and
there
is
no
reason
to believe
it will lessen
its control
efforts
during
the period
of
this variance.
(emphasis
added)
Mobil
Oil
Corporation
v.
EPA,
PCB
86—45,
slip.
op
at
3
(August
14,
1986)
The Board
is at
a loss
to determine how this statement is
inconsistent with the concerns the Board has expressed in this
site—specific rulemaking.
A variance proceeding deals with
temporary relief
and its corresponding
impacts.
A plan for
ultimate compliance
is also essential
in such
a proceeding.
In
a
site—specific~rulemaking,
the issues are much more sweeping.
The
Board must determine whether permanent relief from
a requirement
is justified.
Therefore,
the Board must consider the far
reaching consequences that are incidental
to permanent relief.
In general,
the Board does not believe that the deliberations
in
a site—specific rulemaking
are necessarily bound
by
determinations made in an earlier variance proceeding.
In
85—109
8
particular, even
if the Board viewed
the quoted statement as
controlling,
it would
still not contravene
the Board’s present
concerns.
The statement is qualified by the phrase “during
the
variance period.”
That is,
the statement would not preclude the
Board
from considering
in this rulemaking, situations which could
arise subsequent to the variance period.
Mobil’s statistical
argument for dropping the annual average
is much more convincing.
As Exhibit B to
its Comments, Mobil has
submitted
a report written by James Patterson entitled
“Evaluation of Proposed Ammonia Discharge Limitations
(PCB R84—
16)”.
In that report, Patterson critiques the effluent limits
proposed by the Board at First Notice.
Patterson concludes that the use of a daily maximum plus
a
monthly average limit
is sufficient to describe the performance
level
of
a treatment facility.
He also asserts that the
additional imposition of an annual
average limit is “redundant
if
internally consistent with
the statistical profile
of
performance,
and could render one or more of the other limits
moot if
the
annual average
is
internally inconsistent.”
Specifically, Patterson claims that the annual
average of
8 mg/l,
as proposed by the Board
at
First Notice,
is “statistically
inappropriate” when considering Mobil’s operations during the
period from 1982 to 1986.
Based
on such data, Patterson
concludes that there
is “an approximate 15
to 20 percent
possibility that the
annual
average
limit would be exceeded
in
any one year.”
(P.C.
#1, Exh.
B,
p.
27).
Specific effluent limits can be correlated with percentile
levels which characterize past performance levels.
For example,
a particular limit at the 50th percentile,
for
a given period,
indicates that during that period half the values were below that
limit and half the values exceeded that limit.
(P.C.
#1, Exh.
B,
p. 4).
Based
on
data
taken
from
January,
1982
through
June
1984,
Patterson suggested, at hearing,
a daily maximum of 35 mg/l.
This limit equates to
a 95th percentile level
for that data
base.
That
is,
95 percent of the daily effluent concentrations,
for the period from January 1982 through June 1984,
fell at or
below the 35 mg/l level.
(P.C.
#1, Exh. B,
p.
1,
13).
The Board
proposed this limit at First Notice.
Patterson had also recommended, at hearing,
a 25 mg/l
monthly average, based
on data from January 1982 through June
1984.
However, when that period
is expanded
to
include data
through December
1986, the 95 percentile value
is
22 mg/I.
The
Board proposed
a
20 mg/l monthly standard, which according
to
Patterson,
is equivalent to the 94th percentile value for that
expanded data base.
(P.C.
#1,
Exh.
B,
p.
10, 15).
85—110
9
Patterson
has
also
figured
the
percentile
level
for
an
annual
average
limit
of
8
mg/i.
The
data
base
he
has
used
in
this calculation includes the discharge levels from January,
1982
through December,
1986.
However,
instead of calculating an
annual average according
to the calendar year, Patterson has
plotted 12 month rolling averages.
Specifically,
he has plotted
seventeen
12—month averages with each subsequent 12—month period
beginning
3 months after the previous 12—month period.
That is,
the first period covers the time from January
1,
1982
to December
31,
1982.
The second 12—month period covers the time from April
1,
1982 through March 31,
1983.
The procedure goes on until
17,
12—month periods are defined.
From the plotting of these 12—
month averages, Patterson has calculated that the 8 mg/i annual
average represents the 85th percentile
for
this data base.
(P.C.
#1,
Exh.
B,
p.
22).
However, the Board notes that section
304.104(b) (1) defines
a monthly average as “numerical average of
all daily composites taken during a calendar month.”
(emphasis
added).
By analogy, the Board would expect the annual average
to
be
computed
on
the
basis
of
a
calendar
year.
Using
these percentile figures, Patterson has made further
calculations
to demonstrate
the feasibility of achieving the
proposed limits
under certain scenarios.
Since the Board set the
daily maximum at 35 mg/i, which according
to Patterson is the
95
percentile for performance, Patterson reasons that
in one year,
approximately 18 daily effluent values will
exceed the 35 mg/i
level.
Patterson claims that
if those
18 days occur
all
in one
month,
it would
be impossible
for Mobil
to meet a monthly average
of 25 mg/i
as well as an annual average of
8 mg/i.
If those
18
days of daily exceedances occurred
in two months,
at
9 days
for
each month,
Patterson concludes that Mobil could meet the monthly
standard but that
it would be impossible
to achieve the annual
average.
(P.C.
#1,
Exh.
B,
p.
20).
Patterson also asserts that data show “that when higher
ammonia discharge levels occur, they persist for several
consecutive days.”
In other words, when significantly higher
ammonia concentrations appear
in Mobil’s effluent, such
concentrations tend
to last.
In light of this fact, combined
with the analysis just discussed,
Patterson concludes:
For
hypothetical
but
realistic
situations
wherein
Mobil
might meet
the
proposed daily
maximum
and
monthly
average
limits,
the
imposition
of
the
proposed
annual
average
limit
would
result
in
circumstances
ranges
sic
from
an
impossibility
of
compliance
with the annual average,
to
having
to achieve
an annual average far less than that achieved
in Mobil’s best year of record.
(P.C.
#1,
Exh. B,
p.
28)
85—111
10
Mobil,
itself, characterizes Patterson’s study:
More
alarmingly,
he
Patterson
forecast
reasonable
situations,
based
upon
Mobil’s
actual historical performance data, where the
Joliet
Refinery
discharge
would
likely
violate
the
proposed
annual
standard
even
though
the
treatment
plant
performed
within
the
admittedly
restrictive
daily
maximum/monthly
average
standards
now
being
proposed by the Board.
(Mobil’s emphasis)
(P.C.
#1,
p.
1172).
Mobi.l
is clearly taking the position that
it would be
difficult,
if not impossible,
to comply with an annual average
limitation of
B mg/i.
In light of the above and the
environmental impact at issue
in this proceeding, the Board has
deleted
the annual average limit of 8 mg/l from the rule.
Since
the Board will not utilize an annual average limit,
it
is unnecessary to specifically answer Mobil’s arguments that the
imposition of such a limit is beyond the Board’s authority.
However, at this point,
the Board believes that it does have the
authority
to
impose
an
annual
average effluent limitation.
The
annual
average
used in combination with the monthly and
daily maximum limits, as previously proposed, would have
effectively required
a more stringent performance level when
compared with what would have been required
if only monthly and
daily limits were set.
This position is supported by Mobil’s own
claim that situations could exist where Mobil could meet the
monthly and daily limits and at the same time violate the annual
average.
With the removal of the annual average, Mobil will
be
able
to discharge effluent at higher ammonia concentrations than
what would have been allowed with the annual
average.
Because
the new rule has the effect of allowing Mobil
to discharge more
ammonia when compared
to the previous proposal, the Board will
include
a sunset provision in the rule.
In its First Notice Opinion the Board discussed
the
possibility of
a sunset provision and concluded that a sunset was
unnecessary.
Finally,
it
is the Board’s position that the
record
supports
the
granting
of
permanent
relief
from
the
ammonia
nitrogen
effluent
standard.
In
re
Union
Oil
Company
of
California,
R
84—13,
January
8,
1987,
the
Board
also
granted
Union
Oil
relief from the
ammonia
nitrogen
effluent
standard
with
regard
to
its
Lemont
Refinery.
However,
the
Board
limited
the
relief
to
seven
years.
85—112
11
Such
a
“sunset
provision”,
though,
is
not
necessary
in
this
matter.
The
data
shows
that
Mobil,
unlike
Union,
has
largely
been
successful
in
reducing
the
concentration
of
ammonia
nitrogen
in
its
discharge.
The
Board notes that on an annual
average
Mobil’s
discharge
has
been
quite
close
to
the
3
mg/l standard.
This
is
true
even
in
recent
years
when
the
nitrogen
content
of
the
oil
feedstocks
have
been
high.
The
Board
fully
expects
Mobil
to
continue
its
high
performance
level
concerning
ammonia
nitrogen
concentrations.
The
Board,
therefore,
grants
Mobil
a
permanent
relief
from
Section
304.122(b)
within
the
conditions
listed
in
the
Order.
(emphasis added).
Opinion and Order,
R84—l6, slip.
op. at
7—8
(February
5,
1987).
Although the Board
still expects Mobil
to continue its high
performance levels, without the annual average limit there is no
legal requirement for Mobil
to continue
to produce an effluent
whose annual average would be close to
3 mg/i.
With only the
monthly and daily limits, set at
20 and
35 mg/l respectively,
Mobil
is only legally required
to produce an effluent to meet
those standards.
Consequently, Mobil will be aliowed
to
discharge an effluent of such quality that a yearly average of
the monthly averages could be as high as 20 mg/i.
This
is
in
great contrast to the yearly averages of the monthly averages
for
the years 1983 through 1987 which are set forth on page
5 of this
Opinion.
It
is obvious that with monthly and daily limits set at
20/35,
Mobil will not be required
to maintain the level of
performance that it has achieved
in the past
4 2/3 years.
Consequently, factors, which the Board relied upon at First
Notice
to omit a sunset, have changed such that the Board will
now impose
a sunset.
As in Union,
the Board will terminate this rule on December
31,
1993.
The six years will allow time for improvement of the
Des Plaines’
condition.
As the Board
noted
in Union, upstream
activities by the MSDGC might greatly enhance water quality.
In
re Union Oil Company,
R84—13 slip.
op.
at ii
(March
19,
1987).
The Board may then be
in a better
position to accurately evaluate
the environmental
impact that would result from granting Mobil
permanent relief.
Also,
the six years will give Mobil further
time
to monitor its effluent and perhaps discover
a
technically
feasible and economically reasonable method
for achieving
compliance with the general
3 mg/l limitation.
85—113
12
Mobil
has
asserted
that
an
increase
in
the nitrogen content
of
the
crude
oil
it
refines
correspondingly
increases
its
effluent concentration.
In particular,
it claims that nitrogen
content of the crudes have increased over the years.
The crude
oil nitrogen content at the Joliet refinery has gone from a low
of about 680 parts per million
(ppm)
in 1976
to a high of about
1450 ppm
in 1984.
In
1985,
it dropped
to
a level of 1120 ppm.
Mobil Oil Company, PCB 86—45 at
3.
If Mobil finds
in the future
that
it exceeds the standards on a regular basis,
it can come
before the Board
under another docket to seek relief.
However,
even though
in recent years Mobil’s crude feedstocks have had
a
high nitrogen content, its effluent has been within the limits
set herein.
Mobil will be required to monitor and report its effluent
concentration.
However, exact procedures for monitoring and
reporting effluent concentrations shall
be set forth in the
permit.
Also, Mobil will
be required
to report on an annual
basis the nitrogen content of its feedstock.
Water Quality Standard Relief
Mobil has also requested relief from being liable for
causing the violation of various water quality standards (WQS).
In response to
a U.S. Environmental Protection Agency (USEPA)
Review Statement submitted by the Agency, Mobil modified its
original proposed language addressing the water quality standards
issue.
Essentially, the modified language states that 35
Ill.
Adm. Code 304.105 will apply to Mobil with respect to general use
and secondary contact WQS
for ammonia nitrogen and dissolved
oxygen, “unless such discharge does not cause or contribute
significantly to the violation” of the WQS.
(Mobil Response,
p.
1).
Mobil’s discharge is located approximately 200 feet upstream
of the 1—55 bridge.
The river upstream of the bridge
is
classified as secondary contact, whereas downstream of the
bridge,
the river
is considered general
use.
(R.
125—26).
Consequently, Mobil’s discharge may,
in theory,
impact upon both
secondary contact and general use streams.
The general use water quality standard for total ammonia
nitrogen, given the river’s pH and temperature,
is 1.5 mg/i
(35
Ill.
Adm. Code 302.212).
The general use water quality standard
for dissolved oxygen is
6 mg/l
(35 Ill. Mm. Code 302.206).
Mobil’s impact upon these standards
is discussed in Petitioner’s
Exhibit
3,
a report prepared by an expert witness
for Mobil.
The report shows that the general use standard for ammonia
nitrogen
is exceeded downstream of Mobil’s discharge.
However,
it
is concluded that under worst case conditions
(Mobil
discharging
3 MGD at 40 mg/i into the river flowing at a low
level of 1,186 MGD), Mobil’s discharge would extend by only 1.85
miles the reach of the river which did not meet the ammonia
nitrogen
standards.
(Pet.
Exh.
#3,
p.
16).
85—114
13
Similarly,
the dissolved oxygen standard
is currently
exceeded downstream of Mobil.
However, under
the same worst case
conditions,
Mobil’s discharge would extend by no more than one
mile the reach of the river which did not meet the dissolved
oxygen standard.
(Id.
at
19).
The secondary contact ammonia nitrogen standard
is 2.5 mg/i
for April
through October,
(35 Ill. Mm.
Code 302.407).
It is
apparent from data reported
in Petitioner’s Exhibit #3 that this
standard
is exceeded upstream of Mobil’s discharge.
(Pet.
Exh.
#3,
p.
17).
The secondary contact standard for dissolved oxygen is
4
mg/i
(35 Ill. Adm. Code 302.405).
Data shows that this standard
is exceeded
in the river mile where Mobil discharges.
(Pet. Exh.
#3,
p.
18).
Consequently,
it
is likely, given the upstream
exceedances of the ammonia nitrogen standard, that the dissolved
oxygen standard
is also being violated upstream of Mobil’s
discharge point.
In the USEPA’s Review Statement, the USEPA stated
that
Mobil’s addition
to the river
is “insignificant” with respect
to
water quality violations.
It concluded:
Mobil
should
not
be
granted
relief
from
Section
304.105
but
should
be
required
in
their NPDES permit to,
in addition to standard
effluent
monitoring,
conduct
upstream
and
downstream
ammonia—N
monitoring
at
representative
sampling
points
to
clearly
ascertain whether or
not they are responsible
for
water
quality
standards
violations
for
ammonia—N.
In its First Notice Opinion, the Board
classified Mobil’s
current impact on water quality as “de minimus”.
In their First
Notice comments, Mobil
and the Agency both object to
the Board’s
de minimus characterization.
Upon reconsideration,
the Board
finds the de minimus language to be inappropriate and hereby
rescinds
it.
In its First Notice comments, Mobil requests that the Board
clarify when Section 304.105 would apply to Mobil’s discharge.
(P.C.
#1,
p.
12—13).
Evidently,
Mobil
is referring
to its
modified language that Section 304.105 will not apply unless
Mobil “causes
or contributes significantly”
to
a WQS violation.
The Agency suggests that the Board rule that “compliance with the
proposed effluent limits shall
be considered adequate compliance
with the water quality standards for the purposes of Section
304.105.”
(P.C.
#2,
p.
4). The Board disagrees with both
positions.
85—115
14
The Board
first
adopted
the
language
of
Section
304.105
as
Rule 402 in
1972.
In its adopting Opinion, the Board discussed
the purpose behind the rule:
402
Violation
of
Water
Quality
Standards.
The
numerical
effluent
standards
adopted
today are intended
as basic requirements that
should
be
met
everywhere
as
representing
ordinary good practice
in keeping potentially
-harmful materials out of the waters.
In
some
cases,
because
of
the
low
volume
of
the
receiving
stream
or
the
large
quantities
of
treated
wasted
sic
discharged,
meeting
these
standards
may
not
suffice
to
assure
that
the
stream
complies with
water
quality
standards
set
on
the
basis
of
what
is
necessary to
support
various water
uses.
In
such cases,
the very nature of water quality
standards
requires
that
additional
measures
be
taken
beyond
those
required
by
ordinary
good practice
to reduce further
the discharge
of
contaminants
to
the
stream.
This
would
not
be
so
if
effluents
were
all
required
to
be
as
clean
as
the receiving
stream,
but
in
recognition
of
economic
hardship
we
have
refrained
from
imposing
such
a
requirement
across
the
board.
What
additional measures
are
required
can
be
determined
only
on
the
basis
bf more detailed consideration
of each
stream
in
accordance
with
the
statutory
requirement that different needs may dictate
different
standards.
Rule
402
states
the
principle
that discharges causing violations
of the water quality standards are forbidden,
as
was
the
case
under
the
earlier
regulations,
and
states basic
considerations
for
determining
which
of
a
number
of
contributors
to
an
overloaded
stream
must
take measures
to abate
the problem
(emphasis
added).
In re:
Effluent Criteria; Water Quality
Standards Revisions; and Water Quality
Standards Revisions for
Intrastate
Waters, R70—8; R7l—i4;
R7l—20,
3 PCB 401,
405
(January
6,
1972).
The record indicates 96 percent of the ammonia loading
in
the Des Plaines
is due to the discharges from MSDGC sewage
treatment plants.
Mobil,
itself accounts for 0.3 percent of the
point source loading.
Therefore,
the Des Plaines is
a
type of
river expressly contemplated by the Board when it adopted Rule
402.
“In some cases,...because of large quantities of treated
85—116
15
wasted
sic
discharged, meeting these
effluent
standards may
not suffice to assure that the stream complies with water quality
standards....
In such cases,
as
with this particular stretch of
the Des Plaines
the very nature of water quality standards
requires that additional measures be taken....”
These
“additional measures” equate to the enforcement of Section
304.105.
The reasoning behind Section 304.105
is just as valid
today as
it was
in 1972 when
it was adopted
as Rule 402.
In its 1972 Opinion,
the Board clearly described two lines
of defense
in the protection of a stream’s water quality.
The
first line entails the regulation of effiuents.
The second line,
which
is just as important as the first,
involves enforcement
against a source that causes
a violation of
a water quality
standard.
In the instance at hand, Mobil has justified relief as
to
its effluent discharge.
Due to technical, economic,
and
environmental consideration, the Board will alter Mobil’s
effluent limits.
However, Mobil has not justified
to the Board
the necessity for abandoning completely,
or even partially, this
second line of defense.
In the
record, much has been made about
the relatively poor
quality
of
the
Des
Piaines
River.
The
implication
is
that
the
Board
should
grant
Mobil some sort of relief from Section 304.105
because the water quality standards are already being exceeded.
However, the Board
is not
in the position
to merely preserve the
status quo when water quality standards are being violated
in a
river.
The Board
is to adopt regulations “to promote the
purposes and provisions”
of the Act.
Iii.
Rev. Stat.
1985,
ch.
1111/2, par.
1013
(a).
One of the purposes of the Act
is to
“restore, maintain and enhance the purity of the waters of this
State
in
order
to
protect
health, welfare, property, and the
quality
of
life and
to assure that no contaminants are discharged
into
the
waters
of
the
State.”
Iii.
Rev.
Stat.
1985,
ch.
ill
1/2
~
par.
1011(b).
The Board
is not convinced
that
it
would
be
furthering
the
purposes of the Act by insulating Mobil from an enforcement
action when Mobil
is contributing
to
a WQS violation.
Secondly, any relief from Section 304.105 could be
considered
a de facto WQS revision.
Although the Board has the
authority to revise a WQS, federal law,
under the Federal Water
Pollution Control Act, requires that certain criteria be met
in
the case of such
a revision.
The record does not contain the
necessary information that would be required before the Board
could consider
a WQS change.
Also,
no numerical WQS alternative
is proposed.
Mobil
is merely requesting that Section 304.105 not
apply to Mobil as
it would apply to all other sources.
For all
of the above reasons, the Board will deny that part
of Mobil’s proposal which requests partial relief
from Section
304.105.
85—117
16
Finally,
the Board also believes that the instream
monitoring, as proposed by the USEPA,
is a requirement suitable
for consideration by the Agency as a permit condition.
ORDER
The Board adopts as final
the following rule
to be filed
with the Secretary of State and published in the Illinois
Register.
TITLE
35:
ENVIRONMENTAL PROTECTION
SUBTITLE C:
WATER POLLUTION
CHAPTER
I:
POLLUTION
CONTROL
BOARD
PART
304
EFFLUENT
STANDARDS
SUBPART B:
SITE—SPECIFIC RULES AND
EXCEPTIONS NOT OF GENERAL APPLICABILITY
Section 304.214
Mobil Oil Refinery Ammonia Discharge
a)
This Section applies
to discharges from Mobil
Oil
Corporation’s Refinery, located near Joliet,
into the
Des~Plaines River.
b)
The requirements of Section 304.122(b)
shall not apply
to Mobil’s discharge.
Instead Mobil’s discharge shall
not exceed the following limitations:
CONSTITUENT
CONCENTRATION (mg/i)
Ammonia Nitrogen
Monthly Average
20
Daily Composite
35
c)
Section 304.104(a)
shall
not apply to this Section.
Monthly average and daily composites are as defined
in
Section
304.104(b).
d)
Mobil
shall
monitor
the nitrogen concentration of its
oil
feedstocks
and
report
on
an
annual
basis
such
concentrations
to
the
Agency.
The
report
shall
be
filed
with
the
Agency by January
31
of
each
year.
e)
The provisions of this Section shall
terminate on
December
31,
1993.
(Source:
Added
at 12 Ill. Reg.
effective
)
85—118
17
IT IS SO ORDERED.
Section 41 of the Environmental Protection Act,
Ill. Rev.
Stat.
1985 ch.
111 1/2
par.
1041,
provides
for appeal of final
Orders of the Board within 35 days.
The Rules of the Supreme
Court of
Illinois establish filing requirements.
I, Dorothy M.
Gunn, Clerk of the Illinois Pollution Control
Board,
hereby certifZ~~tthe above Proposed Opinion and Order
was adopted on the
1~1~
day of
________________,
1988, by a
vote of __________________________
~
~.
L ~
Dorothy M.~Gunn,Clerk
Illinois Pollution Control Board
85—119
