DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Search
Criteria:
Outline:
XX.
PM2.5
Modeling
for
Minnesota
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
2
XX.
PM2.5
Modeling
for
Minnesota
XX.
PM2.5
Modeling
for
Minnesota
Document
No.:
OAR­
2003­
0053­
2284.2
Commenter:
Minnesota
Power
Phase:
Reconsideration
Notes:
Docket
Number
2284
is
the
general
comment
cover
letter
(
FDMS
version).
Docket
Number
2284.1
is
the
cover
letter.
Docket
Number
2284.2
is
the
comment
letter.
Also
submitted
were
the
following
attachments:
Docket
Numbers
2284.3,
2284.5,
2284.6,
2284.7,
and
2284.8.
Comment:
MP
is
an
investor
owned
utility
providing
energy
services
to
customers
in
central
and
northeastern
Minnesota
and
Wisconsin.
The
majority
of
MP=
s
electrical
generation
is
from
combustion
of
low
sulfur,
low
mercury
subbituminous
coal.
MP=
s
northern
location
and
high
percentage
of
industrial
customers
who
operate
around­
the­
clock
make
MP
a
winter­
peaking
utility.
Thirteen
large
power
customers
(
requiring
at
least
10
megawatts
of
generating
capacity)
purchase
about
half
the
electricity
IMP
sells.
Because
of
MP=
s
high
percentage
of
industrial
customers
who
are
high
energy
users
and
struggling
to
compete
in
a
competitive
global
market
economy,
we
are
concerned
that
any
further
emission
reductions
applicable
to
electric
generating
units
(
EGU)
be
implemented
with
reasonable
timeframes
and
cost
to
minimize
the
impact
to
residential
and
industrial
customers
alike.
[[
(
2284.2,
p.
2)
]]
In
the
August
5,
2005
CAIR
Petition
for
Reconsideration,
MP
noted
concern
about
several
issues
related
to
CAIR,
including
whether
the
significance
of
Minnesota
emissions
was
correctly
characterized
when
EPA
made
its
determination
for
states
that
will
be
subject
to
the
CAIR
and
whether
EPA=
s
decision
to
carry
over
Acid
Rain
Program
sulfur
dioxide
allowance
allocations
into
the
CAIR
while
applying
a
greater
surrender
ratio
(
required
allowances
per
ton
SO2
emissions)
gives
equitable
treatment
for
National
Ambient
Air
Quality
Standard
attainment
states
like
Minnesota,
where
Acid
Rain
Program
allocations
were
applied
to
a
baseline
in
which
the
majority
of
coal
fired
electric
generating
units
were
already
scrubbed
and
burning
low
sulfur
coal.
These
concerns
were
reinforced
when
EPA
established
that
Minnesota
was
the
only
state
that
EPA=
s
air
quality
modeling
had
determined
to
be
exhibiting
emissions
significance
on
a
nonattainment
area
right
at
the
0.20
ug/
m3
PM2.5
significant
contribution
value
established
by
EPA
in
the
final
CAIR.
[[
(
2284.2,
p.
2)
]]
In
its
November
22,
2005
CAIR
reconsideration
announcement,
EPA
noted
that
it
is
accepting
comments
on
four
issues
related
to
the
final
rule,
including
two
that
relate
directly
to
issues
identified
in
the
Minnesota
Power
August
5,
2005,
Petition
for
Reconsideration
(
inequities
in
sulfur
dioxide
allocation
methodology
and
certain
inputs
to
the
fine
particle
(
PM2.5)
modeling
used
to
determine
Minnesota=
s
inclusion
in
the
CAIR
region
for
PM2.5).
EPA
also
requested
comments
about
EPA=
s
use
of
fuel
adjustment
factors
when
establishing
state
nitrogen
oxides
(
Nox)
budgets
and
EPA=
s
determination
that
Florida
should
be
included
in
the
CAIR
region.
MP
is
directing
our
comments
to
the
issues
addressed
in
the
MP
Petition
for
Reconsideration.
[[
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
3
XX.
PM2.5
Modeling
for
Minnesota
(
2284.2,
p.
2)
]]
Modeling
used
to
determine
Minnesota=
s
inclusion
in
the
CAIR
region
for
PM2.5When
EPA
had
begun
to
make
CAIR
related
modeling
available
to
the
public,
it
became
apparent
that
EPA
had
not
given
proper
consideration
to
emissions
and
emission
rates
from
Minnesota
electric
generation
units.
Specifically,
2010
emissions
performance
from
electric
generating
units
(
EGUs)
affected
by
Xcel
Energy=
s
Metropolitan
Emission
Reduction
Program
(
MEW)
and
emission
rates
for
other
Minnesota
EGUs
(
ref.
May
20,
2005
letter)
had
been
incorrectly
characterized.
EPA
responded
to
some
of
these
concerns
in
its
March
9,2005
(
posted
incorrectly
as
3/
9/
2004)
Memorandum
to
the
CAIR
Docket
in
which
it
assessed
the
impact
on
Minnesota=
s
significance
calculation
from
a
corrected
characterization
of
MERP
emission
reductions
by
applying
a
Minnesota
SO2
and
Nox
emissions
prorating
technique
to
the
result
of
EPA=
s
CMAQ
Version
4.3
modeling
results
released
just
before
the
May
12,2005
posting
of
the
final
CAIR
in
the
Federal
Register.
In
this
>
Emissions
in
Minnesota:
Additional
Analysis=
memorandum,
EPA=
s
proration
methodology
estimated
that
an
adjustment
of
about
16,500
tons
of
Nox
emissions
and
5800
tons
of
SO2
emissions
result
in
a
4.3%
to
4.6%
reduction
in
overall
Minnesota
emissions,
which
in
turn,
results
in
an
estimated
0.01
ug/
m3
PM2.5
shift
in
the
significance
calculation
in
the
Chicago
area,
to
0.20
ug/
m3.
[[
(
2284.2,
pp.
2­
3)
]]
Minnesota
Power's
contractor
(
Environ/
AG)
modeled
Minnesota's
emissions
impacts
on
nonattainment
areas
by
obtaining
files
from
EPA
used
to
run
CMAQ
version
4.3
for
the
CAIR
Final
Rule.
Environ/
AG
CMAQ
version
4.3
model
run
results
replicated
EPA's
Minnesota
model
run
results
as
characterized
in
the
CAIR
Technical
Support
Document,
validating
the
Environ/
AG
modeling
as
a
means
for
characterizing
the
impact
of
Minnesota
emissions.
However,
applying
the
EPA
truncation
technique
resulted
in
an
Environ/
AG
modeled,
Minnesota
PM2.5
contribution
to
the
Chicago
area
that
is
0.01
ug/
m3
lower
than
EPA.
Environ/
AG
also
brought
to
Minnesota
Power's
attention
that
EPA
had
discovered
problems
with
the
CMAQ
version
4.3
model
used
to
characterize
PM2.5
significance,
where
CMAQ
version
4.3
is
not
stable
for
mass
analysis.
Environ/
AG
reported
that
the
use
of
the
more
stable
CMAQ
version
4.5
model
determined
a
result
for
Minnesota's
modeled
PM2.5
contribution
to
Chicago
that
was
0.01
ug/
m3
lower
than
was
determined
by
Environ/
AG
using
CMAQ
version
4.3
when
applying
EPA's
truncating
methodology,
which
is
about
a
5%
shift.
[[
(
See
pp.
3­
7
of
Docket
Number
2284.2
for
a
detailed
discussion
of
this
issue.)
]]

Response:
The
commenter
(
Minnesota
Power,
or
MP)
asked
EPA
to
reconsider
whether
emissions
from
Minnesota
significantly
contribute
to
downwind
nonattainment
of
the
PM2.5
NAAQS.
MP
asserts
that
EPA's
modeling
failed
to
account
for
certain
emissions
reductions
required
by
State
programs
(
especially
those
required
under
the
Minnesota
Emissions
Reduction
Program
or
MERP).
In
granting
reconsideration,
EPA
explained
that
it
was
aware
of
the
emission
reductions
in
question
when
it
made
the
significant
contribution
determinations
in
the
final
CAIR.
EPA
had
accounted
for
these
reductions
during
the
rulemaking
by
conducting
a
sensitivity
analysis
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
4
XX.
PM2.5
Modeling
for
Minnesota
(
available
in
the
CAIR
docket),
but
had
not
conducted
revised
air
quality
modeling
(
70
FR
at
72279­
280).
In
response
to
the
reconsideration
petition,
EPA
conducted
revised
air
quality
modeling
which
used
the
inputs
reflecting
emission
reductions
required
by
the
MERP.
This
modeling
showed
(
consistent
with
the
sensitivity
analysis)
that
Minnesota
contributes
a
maximum
of
0.20
ug/
m3
to
the
downwind
PM
2.5
nonattainment
area
of
Chicago­
Gary­
Lake
County,
IL­
IN.
This
modeling
thus
supported
EPA's
conclusion
that
Minnesota's
contribution
met
the
criteria
in
CAIR
for
determining
"
significant
contribution."
Id.
This
revised
air
quality
modeling
used
the
same
modeling
platform
used
for
all
of
the
air
quality
modeling
in
CAIR.
In
the
Notice
of
Reconsideration,
EPA
solicited
comment
on
the
inputs
used
to
model
Minnesota
emissions,
but
declined
to
reconsider
or
reopen
for
public
comment
issues
relating
to
the
air
quality
modeling
platform
itself.
Id.
at
72280.
Most
of
the
comments
received
on
this
issue
in
response
to
the
Notice
of
Reconsideration
supported
EPA's
conclusion.
These
include
comments
from
the
Minnesota
Pollution
Control
Agency
(
MPCA),
the
entity
with
the
most
direct
knowledge
of
emission
reductions
required
by
state
programs.
EPA
also
received
no
adverse
comments
from
Xcel
Energy,
the
entity
that
entered
into
the
MERP
with
the
MPCA
and
whose
projected
emission
levels
were
the
centerpiece
of
the
reconsideration
petition.
In
fact,
no
other
power
generation
source
in
Minnesota
besides
Minnesota
Power
offered
adverse
comments.
EPA
views
these
comments
as
confirmation
of
the
reasonableness
of
the
modeling
approach
used
by
EPA
to
assess
significance
of
contribution
of
the
State.
EPA
also
views
these
comments
as
confirmation
that
its
revised
modeling
accurately
accounts
for
the
MERP
reductions.
Minnesota
Power
(
MP)
did
not
comment
on
the
revised
emissions
modeling
done
for
power
sector
units
in
Minnesota
and
instead
directed
its
comments
to
the
original
emissions
modeling
done
for
the
final
CAIR
that
did
not
fully
account
for
the
MERP
reductions.
MP
does
not
directly
challenge
EPA's
conclusion
that
the
revised
modeling
accurately
accounts
for
the
emission
reductions
required
by
the
MERP.
MP
claims,
nonetheless,
that
the
model
inputs
for
the
final
CAIR
modeling
(
not
the
modeling
done
for
the
Notice
of
Reconsideration,
as
just
noted)
contain
errors.
To
the
extent
these
alleged
errors
relate
to
the
MERP,
EPA
has
corrected
the
errors
as
explained
above.
The
additional
"
errors"
of
which
MP
complains
relate
to
inputs
regarding
the
projected
2010
emissions
for
certain
units
in
Minnesota.
Although
MP
states
that
EPA
has
mischaracterized
emissions
from
some
units,
EPA
believes
that
the
emissions
projections
done
to
provide
inputs
for
the
revised
air
quality
modeling
described
in
the
Notice
of
Reconsideration
are
appropriate.
EPA
believes
its
method
of
projecting
power
sector
emissions
for
units
in
Minnesota
reflects
a
more
accurate
and
robust
method
for
projecting
emissions
than
the
method
used
by
MP.
However,
MP
claims
that
if
its
own
lower
emissions
were
used
as
inputs
to
the
PM2.5
modeling,
that
modeling
would
show
that
Minnesota's
contribution
is
below
the
PM2.5
significance
threshold
of
0.2
µ
g/
m3.
MP
was
selective
in
its
application
of
its
methodology
for
projecting
emissions
and
EPA
does
not
believe
that
it
is
an
appropriate
method
for
projecting
emissions.
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
5
XX.
PM2.5
Modeling
for
Minnesota
MP
also
comments
that
"
EPA
had
erroneously
assigned
2010
sulfur
dioxide
emission
rates
on
scrubbed
Minnesota
units
at
values
as
much
as
double
that
of
the
performance
levels
posted
in
2001."
MP
Comment
p.
4.
After
reviewing
the
modeling
results,
EPA
is
unable
to
find
any
instances
in
Minnesota
where
EPA
projected
SO2
emission
rates
of
scrubbed
units
from
the
revised
power
sector
modeling
that
are
double
that
of
the
2001
performance
level.
MP
also
claims
that
"
NOx
emission
rates
deviated
between
2001
and
2010
without
supportive
operating
rationale."
The
difference
in
NOx
rates
that
MP
alludes
to
is
again
based
upon
the
modeling
for
the
Final
CAIR,
not
for
the
Notice
of
Reconsideration.
In
addition,
MP's
characterization
is
inaccurate.
EPA's
2010
projections
of
NOx
emission
rates
are
generally
lower
than
2001
NOx
emission
rate
data
for
Minnesota
units.
Also,
the
petitioner
has
also
failed
to
demonstrate
that
EPA's
projected
NOx
emission
rates
are
inaccurate.
Another
comment
from
MP
stated
that
"
the
EPA
IPM
modeling
had
shifted
heat
input
from
large,
lower
emission
units
to
higher
emission
units."
Id.
A
comparison
of
the
historical
data
from
2001
and
2004
with
the
revised
emissions
modeling
does
not
support
this
broad
conclusion.
Heat
input
usage
does
not
change
significantly,
and
although
there
are
some
shifts
in
heat
input
usage
between
2010
EPA
projections
and
the
2001
data,
these
shifts
occur
where
the
IPM
projects
it
will
be
cost­
effective
to
make
relatively
small
changes
to
where
electricity
is
produced.
In
addition,
EPA
does
not
accept
the
suggestion
that
because
a
certain
rate
applied
in
2001
it
should
be
applied
in
2010.
This
argument
is
not
adequate
and
ignores
the
many
other
factors
that
may
change
in
the
future
which
could
cause
a
change
in
the
way
a
unit
produces
electricity.
The
power
sector
is
a
complicated,
interrelated,
and
interdependent
system
of
operation,
and
must
be
looked
at
holistically
to
ascertain
the
sector's
response
to
a
certain
set
of
conditions
or
constraints.
The
petitioner's
approach
selectively
chooses
the
methodology
for
determining
emissions
at
certain
units
and
ignores
the
changes
that
may
occur
at
other
units
as
a
result.
In
addition,
it
is
easy
to
question
the
choices
or
assumptions
that
one
makes
for
selective
forecasts
of
this
nature,
since
methodologies
can
be
developed
to
support
foregone
conclusions,
like
lower
emission
levels
in
a
future
year.
For
this
reason,
EPA
uses
the
Integrated
Planning
Model
to
develop
its
power
sector
emissions
projections.
IPM
is
a
detailed,
sophisticated,
and
comprehensive
electric
power
sector
model
that
is
used
to
derive
all
manner
of
projections
for
the
power
sector
and
is
used
to
develop
the
power
sector
emissions
projections
that
are
used
in
air
quality
modeling.
The
model
accurately
reflects
the
power
sector
and
contains
millions
of
variables
to
best
ascertain
how
specific
facilities
will
produce
electricity
to
meet
demand
in
the
most
cost­
effective
manner
possible.
The
variables
are
based
upon
the
best
available
data,
both
current
and
anticipated,
and
include
permitted
emission
rates
for
units,
unit
efficiency,
cost
data,
and
operational
constraints.
This
model
has
been
used
to
support
the
development
of
Title
IV
of
the
Clean
Air
Act
(
the
Acid
Rain
Program),
the
NOx
SIP
Call,
the
Clean
Air
Interstate
Rule,
the
Clean
Air
Mercury
Rule,
and
the
Clean
Air
Visibility
Rule.
In
addition,
it
is
used
by
the
Federal
Energy
Regulatory
Commission,
private
sector,
nonprofits
research
groups,
States,
and
regional
planning
organizations
for
power
sector
projections.
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
6
XX.
PM2.5
Modeling
for
Minnesota
The
model
has
undergone
extensive
peer­
review
and
scrutiny,
and
EPA
believes
it
is
an
appropriate
tool
for
use
in
developing
power
sector
emission
projections
and
better
accounts
for
the
many
dynamics
that
exist
in
the
power
sector
(
http://
www.
epa.
gov/
airmarkets/
epaipm
index.
html).
MP
does
not
challenge
the
use
of
IPM
for
developing
power
sector
emission
projections
for
certain
units,
but
comments
that
at
other
units,
a
revised
methodology
should
be
used.
EPA
believes
that
a
holistic
approach
is
necessary
and
using
a
modeling
tool
that
reflects
the
integrated
nature
of
the
power
sector
as
accurately
as
possible
is
the
most
rational
approach
to
forecasting
emissions
for
all
units
comprehensively.
To
its
credit,
MP
also
points
out
that
emissions
from
the
Taconite
Harbor
Facility
(
a
facility
that
was
recently
converted
from
an
industrial
source
to
an
electricity
generating
source)
were
not
included
by
EPA
in
either
the
power
sector
emissions
data
or
in
other
emissions
inventory
used
for
CAIR
modeling.
EPA
will
include
the
facility
in
the
next
version
of
the
IPM.
If
the
facility
had
been
included
in
the
inventory,
emissions
in
Minnesota
would
have
been
higher
by
almost
2,000
tons
of
SO2
and
about
1,150
tons
NOx
than
what
EPA
projected
(
according
to
the
commenter).
Since
EPA
did
not
include
this
facility,
EPA
believes
that
its
own
projections
of
emissions
in
Minnesota
underestimate
likely
future
emissions.
MP
also
stated
that
it
is
"
noteworthy
that
there
are
other
reductions
that
Minnesota
Power
has
not
modeled
that
should
warrant
consideration
by
EPA,
including
those
resulting
from
emission
controls
provided
on
Minnesota
BART
eligible
units
for
the
regional
haze
program."
MP
Comment
p.
6.
The
Regional
Haze
program
requires
Best
Available
Retrofit
Technology
or
BART
to
be
installed
and
operational
on
sources
that
the
State
finds
subject
to
BART
within
five
years
after
EPA
approves
a
State's
regional
haze
SIP.
These
SIPs
are
due
in
December,
2007.
EPA
does
not
believe
that
States
will
require
the
installation
of
operation
of
BART
before
2010.
Thus
it
is
highly
unlikely
that
2010
emissions
would
be
affected
by
the
BART
requirements.
In
addition,
MP
does
not
quantify
any
reductions
it
believes
will
occur
due
to
the
application
of
BART
in
Minnesota.
Thus,
MP
has
not
established
that
there
will
be
additional
reductions
due
to
BART
that
must
be
taken
into
account
when
projecting
2010
emissions
for
units
in
MN.
It
is
also
important
to
note
that
EPA
has
determined
that
CAIR
achieves
greater
progress
than
BART,
and
may
be
used
by
States
in
the
CAIR
region
as
an
alternative
to
BART.
In
sum,
EPA
continues
to
believe
its
emission
projections
have
reasonably
accounted
for
emission
trends
within
Minnesota
and
fully
account
for
emission
reductions
attributable
to
the
MERP.
EPA
believes
the
inputs
used
for
the
modeling
discussed
in
the
Notice
of
Reconsideration
are
reasonable
and
rational
projections
of
2010
emissions
in
Minnesota.
For
these
reasons,
EPA
is
not
making
any
additional
changes
to
the
inputs
to
the
PM2.5
modeling
for
Minnesota,
beyond
those
changes
described
in
the
Notice
of
Reconsideration.
For
more
detail
regarding
Minnesota
EGUs
and
EPA
modeling,
please
see
Xcel
spreadsheet
titled
"
Minnesota
EGU
Unit
Summary_
CAIR
Reconsideration.
xls"
in
the
CAIR
docket.
MP
also
notes
that
Environ/
AG's
CMAQ
version
4.3
modeling
shows
a
PM2.5
contribution
to
the
Chicago
area
that
is
0.01
ug/
m3
lower
than
EPA's
modeling
shows.
This
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
7
XX.
PM2.5
Modeling
for
Minnesota
difference
was
caused
by
an
error
of
the
petitioners.
The
petitioner
was
not
properly
following
EPA's
truncation
methodology
for
calculating
PM2.5
contributions,
as
described
in
the
CAIR
Air
Quality
Modeling
Technical
Support
Document
(
EPA­
HQ­
OAR­
2003­
0053­
2151)
(
See
pp
21,
41­
43).
The
petitioner
corrected
this
error
and
submitted
revised
PM2.5
contributions
to
Chicago
(
EPA­
HQ­
OAR­
2003­
0053­
2312)
based
on
petitioner's
CMAQ
version
4.3
modeling.
These
results
replicate
EPA's
contribution
to
Chicago.
MP
also
raises
a
new
issue
in
their
comments.
They
argue
EPA
should
use
a
more
recent
version
of
its
modeling
platform
to
conduct
air
quality
modeling.
However,
EPA
stated
when
granting
reconsideration
that
it
was
not
reopening
any
issues
dealing
with
the
modeling
platforms
used
for
the
CAIR
modeling.
We
reiterate
that
position
here.
EPA
used
CMAQ
4.3
for
all
of
the
air
quality
analyses
conducted
for
the
final
CAIR,
and
provided
full
notice
and
opportunity
to
comment
on
the
appropriateness
of
the
model.
See
69
FR
47828
(
August
6,
2004)(
announcing
plan
to
use
CMAQ
4.3
for
the
final
rule);
see
also
70
FR
25234­
36
(
summarizing
the
use
of
CMAQ
4.3).
There
was
ample
opportunity
to
comment
on
any
issues
regarding
the
adequacy
of
the
model
during
the
rulemaking.
Nor
is
the
existence
of
a
new
iteration
of
the
model
"
grounds
for
 
objection
ar[
ising]
after
the
period
for
public
comment"
(
CAA
section
307
(
d)
(
7)
(
B)).
Predictive
models
are
of
course
open
to
the
possibility
of
updating
and
so
are
often
adjusted.
Such
adjustments
do
not
normally
occasion
new
opportunities
for
comment,
particularly
after
the
close
of
a
rulemaking.
Indeed,
doing
so
would
create
a
perverse
incentive
to
leave
models
unadjusted.
The
ultimate
issue
is
whether
the
model
used
in
the
rulemaking
bears
a
"
rational
relationship
to
the
characteristics
of
the
data
to
which
it
is
applied".
Appalachian
Power
v.
EPA,
249
F.
3d
1032,
1052
(
D.
C.
Cir.
2001).
There
has
already
been
full
opportunity
to
comment
on
this
issue.
For
more
discussion
on
all
issues
related
to
MP's
comments,
see
the
CAIR
Notice
of
Final
Action
on
Reconsideration.

Document
No.:
OAR­
2003­
0053­
2274
Commenter:
Minnesota
Pollution
Control
Agency
Phase:
Reconsideration
Comment:
The
Minnesota
Pollution
Control
Agency
has
reviewed
the
reconsideration
notice
(
EPA­
HQOAR
2003­
0053­
2215)
and
in
particular,
the
information
in
this
notice
relating
to
itemC.
>
PM2.5
Modeling
for
Minnesota=.
We
have
also
reviewed
and
evaluated
information
related
to
item
C.
Contained
in
the
docket.
Based
on
our
review,
we
believe
that
Xcel
Energy=
s
Metropolitan
Emission
Reduction
Project
emission
reductions
have
been
accounted
for
in
a
reasonable
manner
in
the
emission
projections
EPA
used
for
contribution
modeling.
[[
(
p.
1)
]]
Response:
EPA
has
performed
revised
modeling
of
emission
in
Minnesota
and
believes
that
Minnesota
still
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
8
XX.
PM2.5
Modeling
for
Minnesota
meets
EPA's
threshold
for
inclusion
in
the
Clean
Air
Interstate
Rule.
See
the
CAIR
Notice
of
Final
Action
on
Reconsideration
for
further
discussion.
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
9
XX.
PM2.5
Modeling
for
Minnesota
Document
No.:
OAR­
2003­
0053­
2268.1
Commenter:
Northeast
States
for
Coordinated
Air
Use
Management
(
NESCAUM)
Phase:
Reconsideration
Notes:
Docket
Number
2268
is
the
cover
letter.
Docket
Number
2268.1
is
the
comment
letter.
Comment:
Fine
particulate
matter
(
PM2.5)
modeling
for
Minnesota
and
including
Florida
in
the
CAIR
region
for
ozone.
EPA
has
asked
for
comment
on
the
inclusion
of
Florida
in
the
CAIR
region
for
ozone
and
on
revised
modeling
inputs
for
Minnesota.
NESCAUM
is
not
commenting
on
those
specific
issues.
However,
EPA
must
include
States
in
the
CAIR
program
for
which
analyses
demonstrate
that
they
contribute
to
non­
attainment
under
section
110(
a)(
2)(
d)
of
the
Clean
Air
Act.
Should
EPA
choose
to
remove
any
jurisdiction
from
the
CAIR
program,
EPA
must
reduce
the
total
Nox
and
SO2
CAIR
budgets
by
amounts
equal
to
that
jurisdiction=
s
Nox
and
SO2
budgets,
respectively.
The
NESCAUM
States
cannot
attain
the
eight­
hour
ozone
and
PM2.5
National
Ambient
Air
Quality
Standards
without
substantial
reductions
in
direct
and
transported
emissions
of
Nox
and
SO2
across
the
Eastern
U.
S.
We
urge
EPA
to
ensure
that
the
CAIR
program
maximizes
reductions
of
transported
Nox
and
SO2
to
the
extent
feasible.
[[
(
2268.1,
p.
2)
]]
Response:
EPA
is
including
in
CAIR
all
States
that
it
has
determined
significantly
contribute
to
downwind
nonattainment
of
or
interfere
with
maintenance
of
the
PM2.5
and/
or
8­
hour
ozone
NAAQS.
EPA
has
determined
that
Minnesota
is
properly
included
in
the
CAIR
region
for
PM2.5
and
that
Florida
is
properly
included
in
the
CAIR
regions
for
PM2.5
and
8­
hour
ozone..
See
the
CAIR
Notice
of
Final
Action
on
Reconsideration
for
further
discussion.

Document
No.:
OAR­
2003­
0053­
2279.1
Commenter:
Midwest
Generation
Phase:
Reconsideration
Notes:
Docket
Number
2279
is
the
cover
letter.
Docket
Number
2279.1
is
the
comment
letter.
Docket
Number
2278
is
a
duplicate
of
2279
(
cover
letter).
Comment:
MIDWEST
GENERATION
SUPPORTS
EPAS
DETERMINATION
THAT
PM2.5
EMISSIONS
FROM
MINNESOTA
CONTRIBUTE
SIGNIFICANTLY
TO
NONATTAINMENT
IN
ILLINOIS.
Midwest
Generation
supports
EPA=
s
conclusion
that
Minnesota
is
subject
to
the
final
CAIR
based
on
the
Agency's
most
recent
analyses
confirming
that
Minnesota
contributes
significantly
to
nonattainment
of
PM2.5
NAAQS
in
Cook
County,
Illinois.
Generally,
Midwest
Generation
submits
that
air
quality
challenges
should
be
addressed
just
as
they
develop
irrespective
of
political
boundaries.
Indeed,
Congress
recognized
as
much
when
it
enacted
the
>
good
neighbor=
provision
of
the
Clean
Air
Act,
CAA
'
110(
a)(
2)(
D).
Section
110(
a)(
2)(
D)
provides
that
state
SIPs
must
contain
adequate
provisions
prohibiting
in­
state
sources
from
emitting
any
pollutant
in
amounts
that
contribute
significantly
to
nonattainment
of
NAAQS
in
a
downwind
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
10
XX.
PM2.5
Modeling
for
Minnesota
state.
Notably,
in
the
preamble
to
the
final
CAIR,
EPA
noted
the
regional
nature
of
PM2.5
nonattainment,
in
particular.
EPA
explained
its
relatively
low
air
quality
impact
threshold
of
0.20
µ
g/
m3
for
PM2.5,
noting
that
>
PM2.5
nonattainment,
like
ozone,
is
caused
by
many
sources
in
a
broad
region,
and
therefore
may
be
solved
only
by
controlling
sources
throughout
the
region.=
[[
(
2279.1,
p.
7)
]]
In
response
to
Petitioners=
questions
regarding
whether
EPA=
s
modeling
supporting
the
final
CAIR
sufficiently
accounted
for
certain
emissions
reductions
required
by
Minnesota
regulation
(
and,
thus,
whether
Minnesota
was
properly
a
CAIR­
affected
state),
EPA
reviewed
its
prior
analysis
and
concluded
that,
indeed,
the
analysis
did
not
fully
account
for
such
effects
on
future
PM2.5
emissions.
As
a
result,
EPA
projected
future
emissions
a
second
time
using
inputs
revised
downward.
As
revised,
EPA=
s
estimate
of
statewide
Nox
emissions
was
approximately
16,500
tons
lower
and
the
estimate
for
SO2
emissions
about
5,800
tons
lower
relative
to
EPA=
s
prior
analysis.
Even
based
on
these
more
conservative
emissions
projections,
the
same
IPM
modeling
consistently
demonstrated
that
PM2.5
emissions
from
Minnesota
result
in
an
air
quality
impact
in
Cook
County,
Illinois
of
0.2
µ
g/
m3.
[[
(
2279.1,
pp.
7­
8)
]]
EPA
defines
>
significant
contribution=
for
purposes
of
the
>
good
neighbor=
provision
in
terms
of
air
quality
impact.
In
the
final
CAIR,
EPA
makes
clear
that
any
air
quality
impact
on
PM2.5
equal
to
0.2
µ
g/
m3
or
higher
amounts
to
>
significant
contribution,=
interfering
with
attainment
or
maintenance
such
that
imposition
of
CAIR
is
triggered.
Because
EPA=
s
IPM
modeling
showed
that
emissions
within
Minnesota=
s
borders
impact
air
quality
in
Cook
County
at
the
threshold
­
even
after
fully
accounting
for
emissions
reductions
that
are
expected
as
a
result
of
state
regulation
­
EPA
properly
concluded
that
fine
particulate
emissions
in
Minnesota
contribute
significantly
to
the
nonattainment
of
the
PM2.5
NAAQS
in
Cook
County,
Illinois.
Sources
in
Minnesota
aggravate
air
quality
problems
in
the
region
and,
thus,
should
be
required
to
achieve
their
fair
share
of
emissions
reductions.
A
decision
by
EPA
to
exclude
Minnesota
from
the
CAIR
region
would
unfairly
burden
affected
sources
in
Cook
County.
Sources
in
Minnesota
would
be
permitted
to
benefit
from
activity
that
results
in
the
deterioration
of
air
quality
in
Cook
County
without
being
required
to
ameliorate
the
damage.
Sources
in
Cook
County,
on
the
other
hand,
would
be
saddled
unfairly
with
the
costs
of
reducing
emissions
sufficient
to
offset
out­
of­
state
emissions
in
order
to
bring
the
area
into
attainment.[[
(
2279.1,
p.
8)
]]
EPA=
s
determination
represents
sound
policy
as
it
fairly
requires
sources
to
whom
the
exceedance
of
the
relevant
NAAQS
can
fairly
be
traced
to
bear
a
proportionate
share
of
the
costs
for
emissions
control.
Indeed,
it
would
be
unfair
for
EPA
to
not
include
Minnesota
within
the
CAIR
region
given
EPA=
s
analyses
showing
that
upwind
sources
cause
air
quality
impacts
downwind
to
a
degree
that
constitutes
significant
contribution
based
on
EPA=
s
empirical
threshold
for
regulation.
[[
(
2279.1,
p.
8)
]]
Response:
EPA
is
including
in
CAIR
all
States
that
it
has
determined
significantly
contribute
to
downwind
nonattainment
of
or
interfere
with
maintenance
of
the
PM2.5
and/
or
8­
hour
ozone
NAAQS.
EPA
has
determined
that
Minnesota
is
properly
included
in
the
CAIR
region
for
PM2.5
and
that
Florida
is
properly
included
in
the
CAIR
regions
for
PM2.5
and
8­
hour
ozone..
See
the
CAIR
Notice
of
Final
Action
on
Reconsideration
for
further
discussion.
DRAFT
COMMENT
SUMMARY
­
02/
10/
2006
Clean
Air
Interstate
Rule
US
EPA
OAQPS
11
XX.
PM2.5
Modeling
for
Minnesota
