ILLINOIS
POLLUTION
CONTROL BOARD
February 15,
1979
ILLINOIS POWER COMPANY,
Petitioner,
v.
)
PCB 79—7
ENVIRONMENTAL PROTECTION AGENCY,
Respondent..
SHELDON
A.
ZABEL, SCHIFF HARDIN
& WAITE, APPEARED ON BEHALF OF
PETITIONER;
JOHN D. WILLIAMS APPEARED ON BEHALF
OF
THE
ENVIRONMENTAL
PROTEC-
TION AGENCY;
KEVIN GREENE APPEARED
ON
BEITAIJF OF CITIZENS FOR A BETTER ENVIRON-
MENT;
LEWIS GREEN APPEARED ON BEHALF OF COALITION FOR THE ENVIRONMENT.
OPINION AND ORDER OF THE BOARD
(by Mr. Goodman):
This matter was initially filed before the Board on March
25,
1977 by Illinois Power Company
(IPC)
and the Illinois Environ-
mental Protection Agency
(Agency)
as a proposed amendment to Rule
204 of the Air Pollution Control Regulations and was docketed as
R77—9.
Subsequent
to
a hearing on the merits
in this matter,
the
Board promulgated new regulations under R75-5 and R74—2 which,
inter alia, provided for the type of relief requested in R77-9
under an adjudicative-type
procedure.
On February
1,
1979 the
Board redesignated this matter as
a hearing pursuant to the newly
promulgated Rule 204(e)(3)
of Chapter
2:
Air Pollution,
and
assigned it docket number PCB 79-7.
The total record of P77-9
was incorporated into the record of PCB 79-7; R77—9 was dis-
missed,
the Agency was named as Respondent,
and the proceedings
in PCB 79-7 were deemed
in compliance with the proposed procedural
rule in R78—6.
This matter
is therefore now adjudicative
in
nature, and the procedures followed are found to be suitable
under the Board’s procedural
rules and under Rule 204(e)(3)
of
Chapter
2.
IPC owns and operates Baldwin Station,
located in Randolph
County,
Illinois,
which
is
a coal—burning power plant composed of
three steam/electric generating
units that have
a combined design
generating capacity of
1,826 megawatts
at full load.
Baldwin
Station is
a base load facility utilizing Illinois coal of approx-
imately 3.0
sulfur by weight obtained from local mines.
32—563
Since
it is located in a rural area of the State, Baldwin is
subject to compliance with Rule 204(e)
of Chapter
2 and has
decided to petition the Board for approval of
a site-specific
emission rate for sulfur dioxide pursuant to the recently promul-
gated Rule 204(e)(3).
Under Rule 204(e)(3),
IPC bears the burden
of proving
in an adjudicative hearing that its proposed emission
rate will not cause or contribute to a violation of primary or
secondary sulfur dioxide ambient air quality
standards or violate
any applicable Prevention of Significant Deterioration
(PSD)
increment.
Any site-specific limitation approved pursuant to 204(e)(3)
would substitute for that standard determined by Rule 204(e)(l)
or Rule 204(e)(2).
An emission standard approved pursuant to
Rule 204(e)(3) will then be included
as
a condition to operating
permits issued under Rule 103 of Chapter
2,
under the condition
that an ambient monitoring
and dispersion modelling program
shall
be operated for at least one year commencing no later than six
months after the date
of the approval
of the emission rate pur-
suant
to Rule 204(e)(3).
The purpose of the ambient monitoring
and dispersion modelling program is to verify that the site-specific
emission standard will not cause or contribute to violations
of
any applicable primary or secondary sulfur dioxide ambient air
quality standard.
No more than
15 months after the commencement
of the ambient monitoring and dispersion modelling program the
owner or operator of the emission source must apply for a new
operating permit,
submitting at the time
of application a report
containing results
of the monitorinq and modelling program.
The original Rule 204(e)
limited the hourly emissions from
the plant to approximately 81,000 lbs./hr of sulfur dioxide.
The
new Rule 204(e)(1)
calls for an emission limitation of approximately
57,000
lbs./hr.
IPC calculated that utilization of
low—sulfur
coal
in order to meet the new Rule
204(e)(l) would cost approxi-
mately $146,000,000 for the period of 1978 through 1983
(1977
dollars).
IPC therefore employed the services of Environmental
Research
& Technology,
Inc.
(ERT)
to analyze the impact of Baldwin
Station on ambient air quality and to prepare the necessary
materials to permit IPC to implement an intermittent control
system for the Baldwin Station with the ultimate objective
of
devising
a permanant site—specific emission limitation for the
Baldwin Station.
The ERT analysis,
“An Air Quality Assessment
Study for the Baldwin Power Station,H
is contained in the record
as Exhibit
1 and sets forth
in detail the results of that analysis.
ERT as a supplement to the work on
a proposed site—specific
limitation for Baldwin prepared data concerning an intermittent
control system entitled “Design of
a Supplemental Control System
for Baldwin Power Station” which
is contained in the record as
Exhibit
2.
The required validation of the proposed emission
limit will be accomplished using the monitoring
system set forth
in Exhibit
2.
Although Rule 204(e)(3)
calls for a one—year
evaluation study
as opposed to the three-year study requested by
IPC in its Petition,
data collection has already started,
and
there should be sufficient time for IPC to gather the data required
under Rule 204(e)(3)(C).
32—564
3
The total sulfur dioxide emissions expected from Baldwin’s
three boilers under
a maximum
load are approximately 102,000
lbs.!
hr.
This maximum
level
Forms the basis of the
site—specific limitation requested
for Baldwin by IPC.
The U.S.
Environmental Protection Agency
(U.S.
EPA) promulgated
in the
Federal Register
(Vol.
43, No.
118)
certain rules pertaining
to
the PSD of air quality in attainment areas.
Randolph County,
Illinois,
in which Baldwin Station
is situated,
is
a class
2
attainment area for3sulfur dioxide.
The PSD in9emenbs
for class
2 areas are 20 ug/m
~n
an annual
basis,
91 ug!m
for a 24—hour
average,
and 512
ug/m
for
a
3-hour
average
(R.178).
The PSD
limits and the requested site-specific
limitation
noted above are
the basic parameters which TPC must consider
in
their
showing
before the Board.
In order
to
determine
whether
sulfur
dioxide emissions from
the
Baldwin
plant
would
cause
or
contribute
to
a
violation
of
any
of the SO~standards, ERT modelled emissions from the plant using
ERT’s Point
Source
Diffusion Model
(PSDM) Version
5.
This model
is based on the Gaussian plume equation which models short and
long term SO2 concentrations
to
a maximum of
20 km
(12.43 miles)
from the source for each of
16 wind directions,
five stability
classes,
five mixing depths and six wind speed categories
for a
total
of
2,400 possible meteorological conditions
(P.27).
Ground-
level concentrations were not calculated
for distances greater
than 20 km(12.43 mi.)
since the model becomes
inaccurate at
greater distances
(P.111).
It should be noted
that no
ground—level concentrations
from a point source would be expected
to be higher outside
a
20 km
(12.43 miles)
radius
than inside a
20 km radius from that source
(P.152).
Since maximum
load
(firing—rate)
at the Baldwin plant was
determined
to result in the highest ground—level concentrations
(“worst—case”), the emission
Factors associated with maximum load
were used
in the model
(P.31).
Five years
(1960—1964) of actual
meteorological data were used
to determine the sequential SO.~
concentrations
(P.32).
Maximum 3—hour and 24—hour SO~ levels
attributable
to Baldwin were calculated by averaging the appro-
priate 1-hour average concentrations during the specific sequence
of hourly wind speed,
wind direction,
estimated mixing heights
and stabilities
(R.28).
Annual averages were determined by using
a four—dimensional wind—rose,
a joint
frequency
distribution of
wind direction, wind speed,
stability and mixing heights.
A second model
called FUMIG was used
to solve for expected
short-term SO2 concentrations during fumigation of a plume
emitted into
a nocturnal inversion.
FUMIG is
a two—dimensional
model based on the Egan—Mahoney advection—diffusion model
(
EGAMA
)
(P. 28)
*
Hourly surface observation of wind speed and direction,
temperature and local cloud cover were collected at Scott Air
Force Base,
Belleville,
Illinois, approximately 25 miles north of
the Baldwin site.
Upper
level meteorological statistics were
obtained at Columbia, Missouri
(R.31—32).
32—565
4
A third model,
MONITOR, was used primarily as
a tool to
select the preferred SO2 monitoring site locations for IPC’s dual
purpose air quality monitoring network.
The locations for sites
were determined by using the short—term pollutant concentrations
around the Baldwin plant, which were computed by PSDM Version
5,
and the representative frequency distribution of meteorological
conditions
from a
four-dimensional wind-rose
(P.32—33).
The results
of the study
are:
1)
The estima~edpeak annual SO~concentration was eSual
to 28 ug/m
(primary standara
is equal
to 80 ug/m
)
and
occurred at
8—11 km
(4.97-6.84 miles) north of the
Baldwin power plant.
2)
During the five year data base periods
no ground—level
so2 concentrations exceeded 1300 ug/m
(three—hour
secondary standard),
and only
7 concentrations exceeded
1,000 ug/m
(P.38).
(NOTE:
These results are due to
the Baldwin plant alone since background SO2 concentra-
tions were not included in the model.)
For additional
detail
of the modeling study,
see Exhibit number
1.
ERT also analyzed what effect the additional 20,000 lbs. of
SO2 per hour would have on the PSD increment.
The 20,000 lbs./hr.
figure
is determined by subtracting approximately 80,000 lbs./hr.,
which the Baldwin plant was allowed under 204(e),
from the proposed
emission limitation of approximately 102,000
lbs./hr.
This study
found that the theoretical emissions
do not exceed or cause an
excess of the PSD increments for any of the averaged periods
(P.52, Exh.
7).
The appropriate modelled incremental concentrations
and ~he respective allowable increments
are:
293 versus 512
ug/m
for the 3—hour average,364 versus
91 ug!m
for the 24—hour
average, and
6 versus 20
ug,/m
for the annual average.
The
concentration which was compared to the PSD increment was the
second highest modelled concentration that occurred within 12
contiguous months of the highest 502 value.
The Agency also conducted a modelling study on Baldwin’s
impact on PSD using the Agency’s Air Quality Short Term Model.
They found that the proposed increase in emissions would not
violate either the original or the new (as of June
19,
1978)
increments
(R.77—78).
When operating at the maximum firing rate
(101,966 lbs. of SO2 per hour), Baldwin will consume approximately
21
of the available 3-hour PSD increment.
However, even with
Baldwin3operating at full
capacity the full
24—hour increment
of
91 ug/m
is available
for future growth
in the area.
They also
found that the air quality impact on St. Louis from Baldwin will
not exceed 50
of the applicable PSD Increments, which
is the
allowed portion for Illinois sources impacting Missouri, and wiil
not exceed 50
of the PSD Increments
in the vicinity of Kaskaskia
or St. Genevieve,
Missouri which are the closest populated areas
of Missouri to Baldwin.
32—566
5
Aylesworth
of
ERT
described
the
monitoring
network
located
around the Baldwin Power Plant,
the purpose
of the network,
and
its performance to date.
The monitoring network consisted of
eleven monitoring
sites
(SO2 analyzers)
and one 100 meter
(328
feet) meteorological
tower site.
The meteorological
tower site
was composed of wind direction and speed sensors,
a temperature!
temperature difference system, and an EPT standard deviation
computer which was used
to measure the standard deviation of wind
speed and direction.
As of the hearing date,
data capture had
been in excess of
90.
The monitoring network will be used to
demonstrate the ambient concentrations of SO2,
to upgrade the
model used to demonstrate the emission limitation,
and to develop
a data base to demonstrate the proposed emission limitation.
The
model
is scheduled for upgrade on September 15,
1978 and April
1,
1979
(P.59).
As of the hearing
date, the model
was slightly
underpredicting observed concentrations
(R.55).
Mr.
Lewis
C. Green,
an attorney practicing
in the city of
St.
Louis, Missouri,
testified representing Coalition for the
Environment.
Mr. Green urged that the Board not relax Baldwin’s
emission limitations,
citing its nearness
to the city of St.
Louis,
sulfur dioxide problems
in that city,
and the potential
problem with the respect
to growth
in the Wood River and Alton,
Illinois areas.
Mr. Lewis Green,
in addition,
cited potential
problems with sulfates
converted from the sulfur dioxide emissions
and questioned the emphasis
on management of the air quality in
local areas with
no consideration of the long—range transport of
pollutants and its consequences.
Mr. Kevin Green testified on behalf of Citizens for a Better
Environment (CBE) whose primary concern is that any relaxation in
the sulfur dioxide standards should not consume
a large portion
of the increment
so as
to threaten potential growth.
Although
CBE’s position is that IPC should continue to burn Illinois coal
at Baldwin, they think that IPC should investigate the possibility
of conducting
a flue gas desulfurization program on one
of the
Baldwin units.
Based upon consideration of the evidence and testimony
presented by the parties herein,
the Board finds that IPC has
sustained its burden
of proof under Rule 204(e)(3)
of the Board’s
Air Pollution Regulations with a showing that a proposed emission
rate of 101,966
lbs.
of sulfur dioxide per hour in the
aggregate and at a rate not to exceed
6 pounds of sulfur
dioxide per million btu’s of heat input will not under
any foreseeable operating conditions and potential meteorological
conditions cause or contribute
to a violation of any applicable
primary or secondary sulfur dioxide ambient air quality standard
or violate any applicable PSD increment.
The Board will therefore
grant the site—specific limitation
as noted with certain conditions
pursuant
to Rule 204(e)(3).
This Opinion constitutes
the finding of facts and conclu-
sions of
law of the Board in this matter.
32—567
6
ORDER
It
is the Order of the Pollution Control Board that Illinois
Power Company be granted a site—specific mass emission limitation
for sulfur dioxide
for its Baldwin Power Plant of 101,966
lbs.
of
sulfur dioxide per hour
in the aggregate and an emission rate
not to exceed
6 pounds of sulfur dioxide
per
million
btu’s
of heat input pursuant to Rule 204(e)(3)
of
the Board’s
Air Pollution Control Regulations,
subject to the following con-
ditions:
1)
Within 30 days
of
the
date
of
this
Order,
Illinois
Power Company
shall apply to the Agency for a revision
of its operating permit for Baldwin consistent with
this
Opinion
and
Order.
2)
The Agency shall
impose,
as
a condition to a permit to
operate Baldwin Station,
an ambient sulfur dioxide
monitoring and dispersion modelling program designed to
determine
if the emission standard granted herein will
not cause or contribute to violations
of any applicable
primary or secondary sulfur dioxide ambient air quality
standards.
The program shall
be operated for at least
one year commencing
no later than six months after the
date of this Order.
3)
Illinois Power Company shall apply for a new operating
permit no more than 15 months after commencement
of the
ambient monitoring and dispersion modelling program
noted in
(2)
above and shall submit at the time of
application a report containing the results of the
ambient monitoring and dispersion modelling program.
Mr. Dumelle Concurs.
I, Christan
L.
Moffett, Clerk of the Illinois Pollution
Control Board, hereby certify the above Opinion and Order were
adopted on the
~
day of
32ft,4HJJLLL,
,
1979 by a vote of
___
I
~
Christan
L. Moffett, ~lerk
Illinois Pollution Control Board
32—568