ILLINOIS POLLUTION CONTROL BOARD
August 3, 1978
IN THE MATTER OF:
)
THE PETITION OF MONSANTO COMPANY
)
R76-17
FOR A REVISION OF
THE
MERCURY
)
SEWER DISCHARGE STANDARD.
PROPOSED OPINION
AND
ORDER OF
THE
BOARD
(by Mr. Dumelle):
On
August
9,
1976 Monsanto Company requested that a site
specific standard be established which would limit the amount
of mercury discharged from its W.
G. Krurnmrich Plant into
the Village of Sauget sewer system.
The petition was published
in Environmental Register #133 on September
22,
1976.
Hearings
were held on August 23, 1977 at Sauget and October
7,
1977 in
Chicago.
Hearings on the economic impact of this proposal
were held on April
18,
1978
in Chicago and April 25,
1978 in
Springfield.
Monsanto’s mercury discharge has been the subject of
a number of prior variances.
The entire records of those cases
were admitted into the record of this proceeding as Group Exhibit
#1.
On the Agency’s motion excerpts from the records in R70—5
and R76—21 were also admitted.
Monsanto owns and operates the W.
G.
Krunirnrich plant in
Sauget,
Illinois.
The plant employs 1,350 people with a payroll
of over $24 million per year.
The chlor-alkali unit
at
the plant
consists of 22 DeNora mercury cells which produce 45,000 tons
of chlorine each year, which in turn comprises 40 percent of the
plant’s chlorine needs.
In addition,
the chlor-alkali unit produces
potassium hydroxide and sodium hydroxide
(caustic) and hydrogen
which are used in a number of chemical processes by Monsanto.
The wastewater from the chior-alkali unit contains mercury which
alone, and in combination with the discharge from the remainder
of the plant,
exceeds the 0.0005 mg/i sewer discharge standard
in Rule 702(a)
of Chapter
3:
Water Pollution of the Board’s Rules
and Regulations.
EFFECTS ON WATER QUALITY
~ND
UPON FISH
Exhibit
8 describes the results of a survey of mercury
levels in the Mississippi River from October 12-14,
1976.
Out
of 56 samples taken,
only
6 showed detectable levels of mercury
31—223
—2—
using flameless atomic absorption
(0.2 ppb or greater).
Of
these six, only one exceeded the water quality standard for
mercury
(0.5 ppb) and that sample was taken five miles upstream
from the Sauget sewage treatment plant.
Mr. Robert Harness sunimarized the results of fish sampling
surveys on the Mississippi River which showed that the only
recorded violation of the Food and Drug Administration
(FDA)
standard
(0.5 ppm) was upstream from Sauget at Alton.
The high
reading at Alton was 0.6 ppm (R.120—l24).
The USEPA reported
no detectable mercury at Alton and at Kimmswich, Missouri, which
is just below Sauget
(R.125).
Exhibit 31(b)
in R76—21 lists the levels of mercury found
at the water quality stations located throughout Illinois in 1975
and 1976.
The Board hereby takes notice of that exhibit.
On
Page 50 there are 19 total mercury readings from three stations
upstream and one station downstream from Sauget.
The only
violations of the 0.5 ppb water quality standard were readings
of 2.1 and 7.0 ppb approximately five miles above Sauget and
13.0,
0.8 and 2.1 ppb at a point approximately 12 miles down-
stream.
It should be noted that although these data show
violations in the vicinity of Sauget’s discharge,
the violations
were all recorded in 1975.
All six samples below and the one
sample above Sauget in 1976 showed mercury levels below the
0.5 ppb water quality standard.
It would appear then that Monsanto has not contributed to
any violations of water quality in the Mississippi River with
its present discharge.
Since the relief requested in this
proceeding represents
a reduction in mercury
in Monsanto’s
effluent, no adverse impact should be expected.
TECHNICAL FEASIBILITY
On June
1,
1977,
the Supreme Court of Illinois addressed
the issue of what effluent standard should be set for the mercury
discharge from Monsanto’s Krummrich plant.
(Monsanto Company
v. Pollution Control Board, et al.,
67 Ill.2d 276, 367 N.E.2d 684).
The setting for that decision was an appeal of the conditions the
Board had set in a variance proceeding.
The Court held that
Monsanto had to develop more effective pollution control tech-
nology...”to meet the standard which is being addressed in
this proceeding.”
The defense of impossibility was rejected
and the Board’s authority to set “technology forcing” standards
was affirmed in the estalilishment of interim effluent standards
for Monsanto’s mercury discharge.
Monsanto has used a sulfide precipitation system for
mercury removal from the chior—alkali waste stream since 1971
31—224
—3—
(R.41).
Since that time mercury has been eliminated from other
parts of the plant wherever possible
(R.38), and the sulfide
system has been improved
(R..42-52).
The movement of mercury
through the plant has been traced to the point where Monsanto
now
accounts for more mercury than it thought it had in the
system
(R.6i).
The present sulfide precipitation system reduces Monsanto’s
chlor-alkali effluent component to approximately 50 ppb.
In an
attempt to reduce this concentration, a reliable add-on system was
pursued.
A number of these were rejected as unsatisfactory
(R.64—67;
76—79;
162-164).
The best results were obtained from
IMAC-TMR resin which is produced by Akzo Zout Chemie in the
Netherlands.
This system is described in Exhibit
9.
The Akzo
resin can reduce the chlor—alkali effluent by 90 percent to
approximately
5 ppb mercury although its long range performance
cannot be predicted.
Monsanto has already begun to install the
Akzo resin system on the assumption that permanent relief will be
granted
(R.180).
The combination of sulfide precipitation
with the Akzo resin is described in the record as
“best
available technology”
(R.72).
Approximately $1,500,000 has
been budgeted for installation of the Akzo resin system.
Annual operating expenses for the mercury removal system are
expected to increase from $720,000 to $1,500,000
(R.75).
Technology has,
in this case, been forced far enough.
ECONOMIC REASONABLENESS
The proposed standard which Monsanto has offered is not
the only environmentally acceptable alternative.
It is, however,
the only alternative which balances adequate safeguards against
economic disruption.
If this proposal were declined by the Board, Monsanto would
have to wait until a final decision is reached in R76-21.
If the
Board decides to raise the mercury effluent standard to
3 ppb
in that proceeding, Monsanto would be forced to either:
a)
treat
its
entire waste stream down to an average of
3 ppb;
b)
remove
mercury from its process; or c)
close down its chlorine-caustic-
hydrogen
production
facilities
altogether.
An
analysis
of
these
alternatives
follows.
a)
At the April
18, 1978 hearing, Mr. Lee Rogers, one
of the authors of Exhibit
23, the economic impact study prepared
for this proceeding, stated that the estimated cost of treating
the entire flow from the Krurnmrich plant down to
3 ppb would
be $18,251,000 per year
(4/18/78,p.22).
Along with being an
abnormally high cost figure, there is no feasible way to treat
31—225
—4—
flows of this magnitude
(6.12 MGD) down to
3 ppb consistently
(4/l8/78,p.22).
So if such a system were designed and installed
(and none ever has been),
it still might not work.
This would
leave the future of the chlor-alkali unit in doubt since Monsanto
would have to re—evaluate
its decision to extend the life of
the system for another ten years
(R.l68).
The existence of the
chlor-alkali unit at the Krummrich plant makes that plant more
attractive
as
a
potential
site
for
capital
expansion.
If
the
future
of
the
chlor-alkali
unit
becomes
uncertain,
some
other
Monsanto plants outside Illinois might compete more favorably
in Monsanto’s future plans.
(R.l57-159.)
b)
In order to produce chlorine without the use of
mercury cells, Monsanto would have to install either a diaphragm
cell or a membrane cell process.
A 270,000 ton per year diaphragm
cell
unit
would
have
to
be
installed
to
obtain
unit
costs
comparable to the present use of mercury cells
(R.154).
Monsanto stated that the rate of return for such a project was
not sufficient to justify its selection over the alternative
of shutting down the chlorine production facilities and buying
these products on the open market
(R.155).
A membrane cell
could
be
installed
but
this
would
produce
a
maximum
concentration
of only 40
caustic.
Since Monsanto and its customers require
45—50 percent caustic,
an added degree of evaporation/concen-
tration would have
to be employed.
This added step would
offset any advantage of lower energy costs or lower losses
of asbestos and lead associated with the membrane cell process
as compared to the diaphragm cell process.
(R.155—l56).
If
either alternative were followed, Monsanto would be prodiicing
a great deal more chlorine and caustic than it presently
does.
This would force Monsanto into the market to sell these
surpluses which would be impossible with its present corporate
staff
(R.156).
c)
If the chior-alkali unit at the Krummrich plant was
simply shut down, Monsanto would suffer a loss of $100,000,000
gross profits over the ten year period from 1977-1986 (R.157).
This loss would occur because all the chlorine, caustic, and
hydrogen which Monsanto needs would have to be purchased elsewhere.
The only estimate of the economic impact of this alternative is
a loss of $0-24 million in payroll and 0-1350 jobs, but any
loss of jobs
in the East St.
Louis
area
would
be
accented
by
the fact that the plant is located in an economically depressed
area.
(Ex.
23,
p.
155.)
THE PROPOSED STANDARD
Monsanto has requested that its mercury effluent standard
be measured in pounds/day insteadof by concentration.
In its
plan to upgrade the chlor—alkali unit,
$1,500,000 has been allocated
toward reducing water usage
(R.68).
A reduction in flow would
necessarily increase the concentration of mercury in the waste-
31—226
—5—
stream.
Since the Board commends Monsanto’s attempts to reduce
its flow and a mass limitation accounts better for variations
in flow,
the pounds standard will be used.
The proposed monthly average
(0.25 pounds/day) has not
been consistently met by Monsanto.
The data submitted for
1977 through August of that year shows three months
(June,
July, August) which exceeded the limit.
During that same
period the daily average
(0.50 pounds/day) has been exceeded
on ten days (February 8, March
1 and 28, June 17,
22 and 29,
July 10,
28,
29,
30)
(Ex.
21 and 22).
It can be. assumed, then,
that the improvements to the chior-alkali unit,
including the
installation of the Akzo resin system will result in consistent
compliance.
At the April
18,
1978 hearing, Mr. Rogers, the
author of the economic impact study,
stated that Monsanto’s
proposal would allow only a small margin of error
(0.02 pounds/day)
providing the finished effluent from the chlor-alkali effluent
is treateö to a level of
5 ppb (4/l8/78,p.24).
Although the
performance of Monsanto’s improved waste—water treatment
system cannot be firmly established, these proposed standards
fall into a range which is possible with optimum performance.
Hence the Board finds that they are appropriate.
Since the proposed standard can be measured accurately
with the flameless atomic absorption method of analysis, the
Board sees no reason why the more expensive neutron activation
analysis method should be employed (R.137-14l).
The proposed language which gives
a credit to any publicly
owned treatment works which receives Monsanto’s wastewater
is appropriate.
The Board
is endorsing the level of technology
which Monsanto intends to use and no municipal plant, including
Sauget and the proposed regional plant which will receive
Sauget’s wastewater, can treat effectively for mercury
(R.
76—21,
R.445).
If Monsanto’s discharge complies with this proposal but
causes a violation of the mercury effluent standard, no liability
should attach.
This Opinion constitutes the Board’s findings of fact and
conclusions of law in this matter.
ORDER
It is the Order of the Pollution Control Board that Rule 702
of Chapter
3: Water Pollution of the Board’s Rules and Regulations
be amended by the addition of a new subsection
(f) which shall
read as follows:
31—227
—6—
(f)
The Monsanto Company plant located
in the Village of Sauget may discharge mercury
in excess of that allowed by Rules 408(a)
and
702(a), provided the total quantity of mercury
discharged by said plant shall not exceed an
average of 0.25 pounds per day during any cal-
endar month,
nor a maximum of 0.5 pounds during
any one day.
Furthermore, any publicly owned
treatment works which, directly, or indirectly,
receives Monsanto’s wastewater shall be en-
titled to discharge mercury in excess of that
provided in Rule 408(a)
to the extent that
said discharge exceeds Rule 408(a)
because of
Monsanto
‘
s discharge.
I, Christan L.
Moffett, Clerk of the Illinois Pollution
Control Board,
hereby ç~rtifythe above Opinion and Order
were adopted on the
3~
day of
_______________,
1978
by a vote of
_________________
Christan L. Mof
,
Clerk
Illinois Pollut
Control Board
3l—22R