Revised
Clean
Air
Interstate
Rule
PM2.5
Contribution
Modeling
for
Minnesota
U.
S.
Environmental
Protection
Agency
Office
of
Air
Quality
Planning
and
Standards
November
2005
1In
addition
to
using
corrected
utility
emissions
in
Minnesota,
the
revised
2010
Base
Case
also
included
updated
(
lowered)
emissions
for
a
refinery
in
Delaware,
based
on
comments
received
on
the
proposal
to
include
Delaware
and
New
Jersey
in
CAIR.

2Technical
Support
Document
for
the
Final
Clean
Air
Interstate
Rule:
Air
Quality
Modeling
(
Docket
No.
OAR­
2003­
0053­
2151).

3Clean
Air
Interstate
Rule
Emissions
Inventory
Technical
Support
Document
(
Docket
No.
OAR
2003­
0053­
2047).

4Appendix
N
to
40
CFR
Part
50.

5Modeled
plus
monitored
nonattainment
refers
to
those
monitoring
sites
that
are
currently
measuring
nonattainment,
using
data
for
2001­
2003,
and
are
also
projected
to
be
nonattainment
in
the
2010
Base
Case.

6The
contribution
values
are
truncated
at
one
place
to
the
right
of
the
decimal
before
they
are
compared
to
the
significance
criterion.
For
example,
a
contribution
of
0.19
:
g/
m3
is
below
the
significance
threshold.

1
EPA
received
a
petition
for
reconsideration
of
the
Clean
Air
Interstate
Rule
(
CAIR)
that
claimed
that
EPA's
PM2.5
significant
contribution
analysis
overstated
the
2010
emissions
from
certain
utilities
in
Minnesota
and
thereby
overstated
the
contribution
from
Minnesota
to
PM2.5
nonattainment
in
other
(
downwind)
States.
As
described
in
the
CAIR
Notice
of
Reconsideration
(
December
2005),
EPA
agreed
to
remodel
the
PM2.5
contributions
from
Minnesota
using
corrected
utility
emissions
for
this
State.
This
modeling
relied
on
the
same
PM2.5
modeling
platform
as
EPA
used
for
the
final
CAIR
contribution
modeling1,
as
described
in
the
CAIR
air
quality
modeling
technical
support
document2
and
the
emissions
inventory
technical
support
document3.
The
revised
Minnesota
modeling
analysis
included
model
simulations
using
the
Community
Multiscale
Air
Quality
(
CMAQ)
model
for
a
2001
Base
Year,
a
2010
Base
Case
with
the
corrected
emissions,
and
a
2010
run
in
which
all
anthropogenic
emissions
of
sulfur
dioxide
and
nitrogen
oxides
were
removed
from
Minnesota
(
i.
e.,
Minnesota
Zero­
Out
Case).
The
CMAQ
model
predictions
were
used
to
determine
PM2.5
concentrations
at
Federal
Reference
Method
(
FRM)
monitoring
sites
in
the
Eastern
U.
S.
for
the
revised
2010
Base
Case
and
Minnesota
Zero­
Out
Case.
The
projected
PM2.5
concentrations
were
calculated
using
the
same
methodology
as
EPA
used
for
the
CAIR
PM2.5
contribution
modeling,
which
is
referenced
in
the
air
quality
modeling
TSD.
The
PM2.5
values
were
truncated
after
two
places
to
the
right
of
the
decimal
in
a
manner
consistent
with
the
calculation
methods
for
annual
average
PM2.5
design
values
used
to
determine
attainment/
nonattainment
of
the
annual
PM2.5
National
Ambient
Air
Quality
Standard4.
EPA
then
determined
the
contributions
to
PM2.5
at
each
"
modeled
plus
monitored"
nonattainment
site5
by
calculating
the
difference
in
PM2.5
between
the
2010
Base
Case
and
the
Zero­
Out
Case.
EPA's
CAIR
significant
contribution
criterion
for
PM2.5
is
0.2
:
g/
m3
such
that
contributions
of
0.2
:
g/
m3
or
greater
are
significant6.
2
The
revised
contributions
from
Minnesota
to
PM2.5
nonattainment
in
other
States
are
provided
by
county
in
Table
1
along
with
the
corresponding
2010
Base
Case
and
Minnesota
Zero­
Out
Case
PM2.5
concentrations
used
to
calculate
the
contributions.
Note
that,
for
counties
with
more
than
one
modeled
plus
monitored
nonattainment
site,
the
data
for
the
site
with
the
highest
contribution
from
Minnesota
are
shown
in
the
table.
The
results
of
the
revised
Minnesota
modeling
show
that
emissions
in
Minnesota
make
a
significant
contribution
to
PM2.5
nonattainment
in
Cook
County,
Illinois.

Table
1.
Revised
2010
Base
Case
"
modeled
plus
monitored"
PM2.5
nonattainment
concentrations
(:
g/
m3),
Minnesota
Zero­
Out
concentrations,
and
the
contributions
from
emissions
in
Minnesota
to
PM2.5
nonattainment
in
other
States.

State
County
Revised
2010
Base
PM2.5
Revised
2010
Minnesota
Zero­
Out
PM2.5
Revised
Contribution
to
PM2.5
Alabama
Jefferson
Co
18.57
18.55
0.02
Alabama
Russell
Co
16.17
16.16
0.01
Delaware
New
Castle
Co
16.53
16.51
0.02
District
of
Columbia
District
of
Columbia
15.83
15.82
0.01
Georgia
Bibb
Co
16.26
16.26
0.00
Georgia
Clarke
Co
16.38
16.38
0.00
Georgia
Clayton
Co
17.39
17.39
0.00
Georgia
Cobb
Co
16.57
16.56
0.01
Georgia
DeKalb
Co
16.75
16.74
0.01
Georgia
Floyd
Co
16.87
16.86
0.01
Georgia
Fulton
Co
18.02
18.01
0.01
Georgia
Walker
Co
15.43
15.42
0.01
Illinois
Cook
Co
16.60
16.40
0.20
Illinois
Madison
Co
16.66
16.54
0.12
Illinois
St.
Clair
Co
16.24
16.12
0.12
Indiana
Clark
Co
16.51
16.47
0.04
Indiana
Dubois
Co
15.73
15.69
0.04
Indiana
Lake
Co
15.33
15.15
0.18
Indiana
Marion
Co
16.83
16.74
0.09
Indiana
Vanderburgh
Co
15.54
15.48
0.06
Kentucky
Fayette
Co
15.95
15.92
0.03
Kentucky
Jefferson
Co
16.28
16.24
0.04
Maryland
Anne
Arundel
Co
15.25
15.23
0.02
Maryland
Baltimore
City
16.05
16.03
0.02
Michigan
Wayne
Co
17.66
17.56
0.10
State
County
Revised
2010
Base
PM2.5
Revised
2010
Minnesota
Zero­
Out
PM2.5
Revised
Contribution
to
PM2.5
3
New
York
New
York
Co
16.18
16.16
0.02
North
Carolina
Catawba
Co
15.48
15.47
0.01
North
Carolina
Davidson
Co
15.76
15.76
0.00
Ohio
Butler
Co
16.45
16.41
0.04
Ohio
Cuyahoga
Co
16.75
16.69
0.06
Ohio
Franklin
Co
16.99
16.94
0.05
Ohio
Hamilton
Co
17.12
17.08
0.04
Ohio
Jefferson
Co
17.94
17.91
0.03
Ohio
Lawrence
Co
16.11
16.09
0.02
Ohio
Mahoning
Co
15.39
15.35
0.04
Ohio
Montgomery
Co
15.41
15.36
0.05
Ohio
Scioto
Co
18.13
18.11
0.02
Ohio
Stark
Co
17.14
17.10
0.04
Ohio
Summit
Co
16.47
16.42
0.05
Pennsylvania
Allegheny
Co
16.84
16.79
0.05
Pennsylvania
Beaver
Co
15.78
15.74
0.04
Pennsylvania
Berks
Co
15.86
15.84
0.02
Pennsylvania
Cambria
Co
15.14
15.12
0.02
Pennsylvania
Dauphin
Co
15.15
15.13
0.02
Pennsylvania
Delaware
Co
15.58
15.56
0.02
Pennsylvania
Lancaster
Co
16.52
16.50
0.02
Pennsylvania
Philadelphia
Co
16.62
16.60
0.02
Pennsylvania
Washington
Co
15.23
15.19
0.04
Pennsylvania
Westmoreland
Co
15.16
15.13
0.03
Pennsylvania
York
Co
16.47
16.45
0.02
Tennessee
Hamilton
Co
16.90
16.89
0.01
Tennessee
Knox
Co
15.89
15.88
0.01
West
Virginia
Berkeley
Co
15.68
15.67
0.01
West
Virginia
Brooke
Co
16.63
16.60
0.03
West
Virginia
Cabell
Co
17.03
17.02
0.01
West
Virginia
Hancock
Co
17.07
17.04
0.03
West
Virginia
Kanawha
Co
17.56
17.55
0.01
West
Virginia
Marion
Co
15.32
15.30
0.02
West
Virginia
Marshall
Co
15.81
15.78
0.03
West
Virginia
Ohio
Co
15.14
15.11
0.03
West
Virginia
Wood
Co
16.67
16.65
0.02
