ILLINOIS POLLUTION CONTROL BOARD
October
29, 1987
IN THE MATTER OF:
PROPOSAL OF MOBIL OIL CORPORATION
TO AMEND THE WATER POLLUTION
)
R84-l6
REGULATIONS
PROPOSED RULE.
SECOND NOTICE.
PROPOSED 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 (WQS)
(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. Adm. Code
304.105.
On February
4,
1986,
the Agency moved
to file United
States Environmental Protection Agency
(tJSEPA)
comments,
and
on
February
7,
1986,
Mobil filed
its response
to USEPA comments
which contained amended proposed
language.
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
is 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 is granted.
82—575
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
Iii.
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 has accepted and
fully considered
these
late
filings.
Mobil
is currently operating under
a variance from
3
mg/l
ammonia nitrogen effluent standard of 35
Ill. 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/i 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 (&~TP)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.
Mobil
is requesting that its effluent limits for ammonia
nitrogen be
set at
25 mg/l for
a monthly average and 40 mg/i
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
82—576
3
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 nitrificatiori
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/i
(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/i 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/i 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/i standard could only be achieved by the
ion
exchange
process.
He
stated
that
“fun
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
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 from
July,
1982 through December
31,
1983, Mobil’s discharge
constitutes 0.3 percent of the river’s total point source loading
of ammonia nitrogen.
(P.
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
82—57 7
4
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.
(P.
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/i
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.
(P.
145—6).
The
river
would
flow
approximately 1.85 miles before returning
to
the original ammonia
nitrogen
concentration.
(P.
187—88).
If
it
is
assumed
that
a
0.101 mg/i
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/i
river
concentration,
the
monetary
loss
directly
attributable
to
Mobil
would
be $6,448 per year.
(P.
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.
(P.
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).
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/i
monthly average and
a
40 mg/i daily maximum. These limitations
were determined
by evaluating
the historical performance data of
the WWTP.
According
to Mobil, these limits are necessary to
82—578
5
account for fluctuations
in the effluent concentrations.
Studies
indicate
that the WWTP consistently removes
a
17 mg/i 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—monthiy 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/i respectively.
Mobil Oil Company, PCB 86—45
at
2.
However,
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/i 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
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—monthiy Progress Report.*
82—579
6
methods thereby increasing
the ammonia nitrogen concentration
in
its discharge.
The Agency proposed
a
10 mg/i monthly average,
a
30 mg/i daily maximum,
and
a
5 mg/i 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/i;
daily composite,
35 mg/i;
and and yearly
average,
8 mg/i.
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
ing/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/i
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
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.
82—580
7
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)
(P.
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.
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
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 P84—
16)”.
In that report, Patterson critiques the effluent limits
proposed by the Board at First Notice.
82—581
B
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/i,
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.
~l,
Exh.
B,
p.
4).
Based
on data taken from January,
1982 through June 1984,
Patterson suggested,
at hearing,
a daily maximum of 35 mg/i.
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/i 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/I
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 has proposed
a 20 mg/i monthly standard, which according to
Patterson,
is equivalent to
the 94th percentile value
for that
expanded data base.
(P.C.
fl, Exh.
B,
p. 10,
15).
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 are 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
82—582
9
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
b~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 has the
daily maximum at 35 mg/l, 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)
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).
82—583
10
Mobil
is clearly taking
the position that
it would be
difficult,
if not impossible,
to comply with an annual average
limitation of
8 mg/i.
The Board
is reluctant to impose
a
limitation on the proponent of
a site—specific rulemaking when
the proponent believes that compliance with the limit
is not
achievable.
In light of this and the environmental impact at
issue
in this proceeding,
the Board will delete
the annual
average
limit
of
B
mg/l
from
the
proposed
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
proposed
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
this
new
proposal.
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,
P
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.
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/i
standard.
This
is
true
even
in
recent
years
when
the
nitrogen
content
of
the
oil
feedstocks
have
been
82—584
11
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,
P84—16,
slip.
op.
at
7—B
(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/i
respectively,
Mobil
is only legally required
to produce an effluent to meet
those standards.
Consequently, Mobil will be allowed
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 Plairies’ 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 11
(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 the
general
3
mg/i
limitation.
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
01.
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.
82—585
12
Mobil will
be required
to monitor
and report its effluent
concentration.
However, procedures
for monitoring and reporting
effluent concentrations, will also be set forth
in
the permit.
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 US.
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.
Adrn.
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.
(P.
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.
Mm.
Code
302.212).
The
general
use
water
quality
standard
for
dissolved
oxygen
is
6
mg/i
(35
Ill.
Adm.
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).
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).
82—586
13
The
secondary
contact
standard
for
dissolved
oxygen
is
4
mg/i
(35 Ill.
Adrn.
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
deminimus characterization.
Upon reconsideration, the Board
finds
the
de
ininimus
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.
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
discharged,
meeting
these
82—587
14
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
of 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, P70—8;
P71—14;
R71—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
wastewater 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 Piaines
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 effluents.
The second line,
which
is just as important as the first,
involves enforcement
82—588
15
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
Plaines
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.
Ill.
Rev.
Stat.
1985,
ch.
111
1/2
,
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.”
Ill.
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
Protection 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.
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 directs that Second Notice of the following
proposed
rule be submitted
to the Joint Committee on
Administrative Rules.
82—589
16
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 the 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
11 Iii. Reg.
effective
IT
IS SO ORDERED.
82—590
17
I, Dorothy
M. Gunn,
Clerk of the
Illinois Pollution Control
Board, hereby certify that the above Proposed Opinion and Order
was adopted on the
~?~day
of
~
,
1987,
by
a
vote
of
7
-
0
Dorothy
M.
unn,
Clerk
Illinois
Pollution
Control
Board
82—591
