Memo
To:
Memo
to
Docket
No.
OAR­
2002­
0076
From:
Thomas
E.
Rosendahl,
Engineer,
U.
S.
EPA
Office
of
Air
Quality
Planning
and
Standards
Air
Quality
Strategies
and
Standards
Division
Integrated
Policy
and
Strategies
Group,
C504­
02
RTP,
NC
27713
Date:
June
15,
2005
Subject:
Roll­
back
Analysis
The
material
that
follows,
documents
a
simple
roll­
back
analysis
on
five
National
Parks
and
Wilderness
areas
and
the
projected
changes
in
the
visibility
parameters
that
would
be
expected.
Write
up
of
a
Simple
Roll­
back
Analysis
A
simple
roll
back
analysis
was
conducted
for
five
National
Parks
and
Wilderness
Areas
using
the
following
assumptions
and
methodology.
The
assumptions
were:

To
use
a
NEI99
version
3
(
NEIv3)
facility
data
set
for
establishing
a
baseline
emissions
inventory
of
facilities
emitting
greater
than
250
tons
annually
of
SO2
or
of
NOx
or
of
PM10.

To
use
an
EGU
BART­
eligible
emission
inventory
data
set
which
is
based
on
NEIv3,
but
adjusted
for
2001
annual
CEM
emissions,
as
the
EGU
BARTeligible
facility
data
set.

To
use
a
nonEGU
BART­
eligible
emission
inventory
data
set
which
is
based
on
NEIv3,
but
adjusted
for
2001
annual
CEM
emissions,
as
the
non
EGU
BART­
eligible
facility
data
set.

To
use
2001
to
2003
IMPROVE
data
as
the
air
quality
indicators
at
the
five
areas
being
analyzed.

To
use
the
following
control
assumption:
that
SO2
emissions
from
BART
eligible
sources
would
be
reduced
by
90%
and
that
NOx
emissions
from
BART
eligible
sources
would
be
reduced
by
50%.

The
roll
back
methodology
involved
the
use
of
a
geospatial
boundary
file
of
the
five
Class
1
areas
that
contains
the
polygon
description
of
each
area
and
its
related
spatial
coordinates
for
the
five
National
Parks
and
Wilderness
areas
being
analyzed.
Next,
a
MapInfo
GIS
system
was
used
to
identify
a
250
kilometer
buffer
zone
around
the
boundary
of
each
area
and
identify
from
the
three
emissions
data
sets
the
facilities
that
are
within
that
buffer
zone.
From
these
subsets
of
emissions
data
for
each
area
the
"
Baseline
Total"
that
is
the
annual
tonnage
of
SO2
plus
NOx
was
obtained,
along
with
the
"
BART
eligible
SO2"
tonnage
and
the
"
BART
eligible
NOx"
tonnage.

The
simple
roll
back
of
any
air
quality
indicator
is
then:

Baseline
Total
 
[(
BART
eligible
SO2
*
0.9)
+
(
BART
eligible
NOx
*
0.5)]
(
The
Air
Quality
Indicator)
x
Baseline
Total
except
for
deciview
which,
because
of
its
logarithmic
relationship,
is
calculated
from
the
B­
extinction
indicator
(
Bext)
using
the
formula:

Deciview
=
10*
LN((
Bext+
10)/
10)

These
resulting
percent
reduction,
or
roll
back
of
the
visibility
parameters,
represents
the
most
optimistic
percent
reduction
that
one
would
expect
from
controls
on
BART
eligible
sources
for
two
reasons.
First,
because
it
only
accounted
for
point
sources,
not
the
total
of
all
point,
area
and
mobile
emission
activities
within
the
250
km
buffer
zone,
which
if
it
could
have
been
accounted
for
would
have
increased
the
size
of
the
"
Baseline
Total"
and
therefore
would
have
driven
the
multiplier
ratio
nearer
to
1.0.
Second,
this
simple
roll
back
didn't
project
the
effects
of
the
expected
CAIR
control
activities
in
future
years,
which
if
it
could
have
been
accounted
for
would
have
reduced
the
amount
of
SO2
and
NOx
tonnages
in
the
bracket
that
is
subtracted
from
the
"
Baseline
Total"
in
the
numerator
and
therefore
would
have
driven
the
multiplier
ratio
nearer
to
1.0.
Therefore,
the
justification
for
the
previous
statement
that
this
analysis
represents
the
most
optimistic
percent
reduction
that
one
would
expect
from
controls
on
BART
eligible
sources.

The
results
show
that
the
best
that
could
be
expected
for
a
2003
visibility
projection
in
the
five
areas
if
BART
had
been
implemented
on
all
BART
eligible
sources
within
250
kilometers
of
the
Class
1
area
boundary
but
before
any
CAIR
reductions
is:

A
change
from
24.1
deciview
to
22.3
deciview
at
Mammoth
Cave
NP
A
change
from
22.7
deciview
to
20.0
deciview
at
Sipsey
Wilderness
A
change
from
21.4
deciview
to
19.4
deciview
at
Mingo
Wilderness
A
change
from
13.0
deciview
to
12.3
deciview
at
Theodore
Roosevelt
NP
A
change
from
7.7
deciview
to
7.7
deciview
at
Yellowstone
NP
The
following
pages
show
a
page
for
each
area
which
contains
the
details
of
the
resulting
air
quality
indicators
as
a
result
of
applying
this
simple
rollback
relationship.
Mammoth
Cave
NP
Mammoth
Cave
Roll­
Back
Analysis,
Facilities
only
with
greater
than
250
annual
tons.

2,766,302
 
[(
SO2
*
0.9)
+
(
NOx
*
0.5)]
Estimate
of
air
quality
impact
=
(
Air
Quality
Indicator)
x
2,766,302
2,766,302
 
[(
443,621
*
0.9)
+
(
242,154
*
0.5)]
Estimated
impact
=
(
Air
Quality
Indicator)
x
2,766,302
Estimated
impact
=
(
Air
Quality
Indicator)
x
0.81
 
The
Roll­
Back
Factor
for
Mammoth
Cave
Mammoth
Cave,
Estimated
Annual
Air
Quality
Impacts
with
BART
Tmass
Bext
Deciview
2003,
1
yr
annual
average
0.81
*
13.9
=
11.3
0.81
*
101.8
=
82.6
From
24.1
to
22.3
2001_
2003,
3
yr
annual
average
0.81
*
14.9
=
12.1
0.81
*
105.5
=
85.6
From
24.5
to
22.6
Mammoth
Cave,
Estimated
Daily
Air
Quality
Impacts
Year,
Daily
unit
Air
Quality
Indicator
Est.
Air
Quality
Impact
Day
of
year
impact
occurred
2003,
1st
highest
Peak
Daily
Extinction
0.81
*
378
=
306.2
168
2003,
2nd
highest
Peak
Daily
Extinction
0.81
*
306
=
247.9
201
2003,
3rd
highest
Peak
Daily
Extinction
0.81
*
297
=
240.6
252
2003,
4th
highest
Peak
Daily
Extinction
0.81
*
258
=
209.0
228
2003,
5th
highest
Peak
Daily
Extinction
0.81
*
231
=
187.1
177
2003,
1st
highest
Peak
Daily
SO4
0.81
*
25.0
=
20.3
252
2003,
2nd
highest
Peak
Daily
SO4
0.81
*
24.7
=
20.0
168
2003,
3rd
highest
Peak
Daily
SO4
0.81
*
21.7
=
17.6
228
2003,
4th
highest
Peak
Daily
SO4
0.81
*
19.9
=
16.1
201
2003,
5th
highest
Peak
Daily
SO4
0.81
*
17.9
=
14.5
255
2003,
1st
highest
Peak
Daily
NO3
0.81
*
7.3
=
5.9
18
2003,
2nd
highest
Peak
Daily
NO3
0.81
*
6.2
=
5.0
39
2003,
3rd
highest
Peak
Daily
NO3
0.81
*
5.7
=
4.6
42
2003,
4th
highest
Peak
Daily
NO3
0.81
*
5.7
=
4.6
24
2003,
5th
highest
Peak
Daily
NO3
0.81
*
5.5
=
4.5
354
2003,
1st
highest
Peak
Daily
PM2.5
0.81
*
33.9
=
27.5
168
2003,
2nd
highest
Peak
Daily
PM2.5
0.81
*
31.7
=
25.7
252
2003,
3rd
highest
Peak
Daily
PM2.5
0.81
*
31.0
=
25.1
201
2003,
4th
highest
Peak
Daily
PM2.5
0.81
*
29.0
=
23.5
255
2003,
5th
highest
Peak
Daily
PM2.5
0.81
*
27.9
=
22.6
228
Mammoth
Cave,
EI
>=
250tons
SO2
or
NOX,
annual
tons.
Mammoth
Cave,
NonEGU
BART
Eligible,
annual
tons.
Mammoth
Cave,
EGU
Bart
Eligible,
annual
tons.
Sum
BART
SO2
1,904,402
5,235
438,386
443,621
NOx
861,900
5,627
236,527
242,154
Sum
2,766,302
10,862
674,913
685,775
Sipsey
Wilderness
Sipsey
Wilderness
Roll­
Back
Analysis,
Facilities
only
with
greater
than
250
annual
tons.

1,535,448
 
[(
SO2
*
0.9)
+
(
NOx
*
0.5)]
Estimate
of
air
quality
impact
=
(
Air
Quality
Indicator)
x
1,535,448
1,535,448
 
[(
361,032
*
0.9)
+
(
168,827
*
0.5)]
Estimated
impact
=
(
Air
Quality
Indicator)
x
1,535,448
Estimated
impact
=
(
Air
Quality
Indicator)
x
0.73
 
The
Roll­
Back
Factor
for
Sipsey
Wilderness
Sipsey
Wilderness,
Estimated
Annual
Air
Quality
Impacts
with
BART
Tmass
Bext
Deciview
2003,
1
yr
annual
average
0.73
*
15.6
=
11.4
0.73
*
87.1
=
63.9
From
22.7
to
20.0
2001_
2003,
3
yr
annual
average
0.73
*
17.0
=
12.5
0.73
*
91.5
=
67.1
From
23.2
to
20.4
Sipsey
Wilderness,
Estimated
Daily
Air
Quality
Impacts
Year,
Daily
unit
Air
Quality
Indicator
Est.
Air
Quality
Impact
Day
of
year
impact
occurred
2003,
1st
highest
Peak
Daily
Extinction
0.73
*
252
=
184.0
237
2003,
2nd
highest
Peak
Daily
Extinction
0.73
*
194
=
141.6
255
2003,
3rd
highest
Peak
Daily
Extinction
0.73
*
193
=
140.9
222
2003,
4th
highest
Peak
Daily
Extinction
0.73
*
190
=
138.7
252
2003,
5th
highest
Peak
Daily
Extinction
0.73
*
187
=
136.5
207
2003,
1st
highest
Peak
Daily
SO4
0.73
*
20.4
=
14.9
237
2003,
2nd
highest
Peak
Daily
SO4
0.73
*
15.8
=
11.5
222
2003,
3rd
highest
Peak
Daily
SO4
0.73
*
14.8
=
10.8
252
2003,
4th
highest
Peak
Daily
SO4
0.73
*
14.6
=
10.7
207
2003,
5th
highest
Peak
Daily
SO4
0.73
*
14.0
=
10.2
255
2003,
1st
highest
Peak
Daily
NO3
0.73
*
6.7
=
4.9
60
2003,
2nd
highest
Peak
Daily
NO3
0.73
*
4.6
=
3.4
18
2003,
3rd
highest
Peak
Daily
NO3
0.73
*
4.3
=
3.1
57
2003,
4th
highest
Peak
Daily
NO3
0.73
*
4.3
=
3.1
24
2003,
5th
highest
Peak
Daily
NO3
0.73
*
3.8
=
2.8
15
2003,
1st
highest
Peak
Daily
PM2.5
0.73
*
32.2
=
23.5
237
2003,
2nd
highest
Peak
Daily
PM2.5
0.73
*
27.4
=
20.0
177
2003,
3rd
highest
Peak
Daily
PM2.5
0.73
*
25.0
=
18.2
255
2003,
4th
highest
Peak
Daily
PM2.5
0.73
*
23.5
=
17.2
207
2003,
5th
highest
Peak
Daily
PM2.5
0.73
*
23.5
=
17.2
252
Sipsey
Wilderness,
EI
>=
250tons
SO2
or
NOX,
annual
tons.
Sipsey
Wilderness,
NonEGU
BART
Eligible,
annual
tons.
Sipsey
Wilderness,
EGU
Bart
Eligible,
annual
tons.
Sum
BART
SO2
1,046,660
14,304
346,728
361,032
NOx
488,788
24,026
144,801
168,827
Sum
1,535,448
38,330
491,529
529,859
Mingo
Wilderness
Mingo
Wilderness
Roll­
Back
Analysis,
Facilities
only
with
greater
than
250
annual
tons.

1,415,850
 
[(
SO2
*
0.9)
+
(
NOx
*
0.5)]
Estimate
of
air
quality
impact
=
(
Air
Quality
Indicator)
x
1,415,850
1,415,850
 
[(
224,392
*
0.9)
+
(
185,862*
0.5)]
Estimated
impact
=
(
Air
Quality
Indicator)
x
1,415,850
Estimated
impact
=
(
Air
Quality
Indicator)
x
0.79
 
The
Roll­
Back
Factor
for
Mingo
Wilderness
Mingo
Wilderness,
Estimated
Annual
Air
Quality
Impacts
with
BART
Tmass
Bext
Deciview
2003,
1
yr
annual
average
0.79
*
18.3
=
14.5
0.79
*
75.2
=
59.5
From
21.4
to
19.4
2001_
2003,
3
yr
annual
average
0.79
*
21.0
=
16.6
0.79
*
84.5
=
66.9
From
22.5
to
20.4
Mingo
Wilderness,
Estimated
Daily
Air
Quality
Impacts
Year,
Daily
unit
Air
Quality
Indicator
Est.
Air
Quality
Impact
Day
of
year
impact
occurred
2003,
1st
highest
Peak
Daily
Extinction
0.79
*
208
=
164.3
185
2003,
2nd
highest
Peak
Daily
Extinction
0.79
*
190
=
150.1
194
2003,
3rd
highest
Peak
Daily
Extinction
0.79
*
153
=
120.9
206
2003,
4th
highest
Peak
Daily
Extinction
0.79
*
143
=
113.0
188
2003,
5th
highest
Peak
Daily
Extinction
0.79
*
139
=
109.8
197
2003,
1st
highest
Peak
Daily
SO4
0.79
*
19.0
=
15.0
173
2003,
2nd
highest
Peak
Daily
SO4
0.79
*
19.0
=
15.0
185
2003,
3rd
highest
Peak
Daily
SO4
0.79
*
17.8
=
14.1
194
2003,
4th
highest
Peak
Daily
SO4
0.79
*
13.1
=
10.3
206
2003,
5th
highest
Peak
Daily
SO4
0.79
*
12.8
=
10.1
188
2003,
1st
highest
Peak
Daily
NO3
0.79
*
7.1
=
5.6
95
2003,
2nd
highest
Peak
Daily
NO3
0.79
*
6.3
=
5.0
5
2003,
3rd
highest
Peak
Daily
NO3
0.79
*
4.4
=
3.5
92
2003,
4th
highest
Peak
Daily
NO3
0.79
*
4.2
=
3.3
17
2003,
5th
highest
Peak
Daily
NO3
0.79
*
4.1
=
3.2
77
2003,
1st
highest
Peak
Daily
PM2.5
0.79
*
34.3
=
27.1
194
2003,
2nd
highest
Peak
Daily
PM2.5
0.79
*
29.1
=
23.0
185
2003,
3rd
highest
Peak
Daily
PM2.5
0.79
*
26.3
=
20.8
182
2003,
4th
highest
Peak
Daily
PM2.5
0.79
*
26.0
=
20.5
197
2003,
5th
highest
Peak
Daily
PM2.5
0.79
*
23.3
=
18.4
206
Mingo
Wilderness,
EI
>=
250tons
SO2
or
NOX,
annual
tons.
Mingo
Wilderness,
NonEGU
BART
Eligible,
annual
tons.
Mingo
Wilderness,
EGU
Bart
Eligible,
annual
tons.
Sum
BART
SO2
931,856
18,484
205,908
224,392
NOx
483,994
16,969
168,893
185,862
Sum
1,415,850
35,453
374,801
410,254
Theodore
Roosevelt
NP
Theodore
Roosevelt
NP
Roll­
Back
Analysis,
Facilities
only
with
greater
than
250
annual
tons.

322,626
 
[(
SO2
*
0.9)
+
(
NOx
*
0.5)]
Estimate
of
air
quality
impact
=
(
Air
Quality
Indicator)
x
322,626
322,626
 
[(
26,313
*
0.9)
+
(
10,733
*
0.5)]
Estimated
impact
=
(
Air
Quality
Indicator)
x
322,626
Estimated
impact
=
(
Air
Quality
Indicator)
x
0.91
 
The
Roll­
Back
Factor
for
Theodore
Roosevelt
NP
Theodore
Roosevelt
NP,
Estimated
Annual
Air
Quality
Impacts
with
BART
Tmass
Bext
Deciview
2003,
1
yr
annual
average
0.91
*
10.2
=
9.3
0.91
*
26.7
=
24.3
From
13.0
to
12.3
2001_
2003,
3
yr
annual
average
0.91
*
10.9
=
9.9
0.91
*
27.7
=
25.2
From
13.3
to
12.6
Theodore
Roosevelt
NP,
Estimated
Daily
Air
Quality
Impacts
Year,
Daily
unit
Air
Quality
Indicator
Est.
Air
Quality
Impact
Day
of
year
impact
occurred
2003,
1st
highest
Peak
Daily
Extinction
0.91
*
78.2
=
71.2
249
2003,
2nd
highest
Peak
Daily
Extinction
0.91
*
70.7
=
64.3
45
2003,
3rd
highest
Peak
Daily
Extinction
0.91
*
68.0
=
61.9
240
2003,
4th
highest
Peak
Daily
Extinction
0.91
*
63.2
=
57.5
66
2003,
5th
highest
Peak
Daily
Extinction
0.91
*
59.5
=
54.1
51
2003,
1st
highest
Peak
Daily
SO4
0.91
*
5.6
=
5.1
66
2003,
2nd
highest
Peak
Daily
SO4
0.91
*
4.9
=
4.5
45
2003,
3rd
highest
Peak
Daily
SO4
0.91
*
3.8
=
3.5
228
2003,
4th
highest
Peak
Daily
SO4
0.91
*
3.4
=
3.1
51
2003,
5th
highest
Peak
Daily
SO4
0.91
*
2.9
=
2.6
171
2003,
1st
highest
Peak
Daily
NO3
0.91
*
3.2
=
2.9
48
2003,
2nd
highest
Peak
Daily
NO3
0.91
*
3.0
=
2.7
114
2003,
3rd
highest
Peak
Daily
NO3
0.91
*
2.9
=
2.6
45
2003,
4th
highest
Peak
Daily
NO3
0.91
*
2.8
=
2.5
12
2003,
5th
highest
Peak
Daily
NO3
0.91
*
2.8
=
2.5
51
2003,
1st
highest
Peak
Daily
PM2.5
0.91
*
20.2
=
18.4
249
2003,
2nd
highest
Peak
Daily
PM2.5
0.91
*
16.8
=
15.3
240
2003,
3rd
highest
Peak
Daily
PM2.5
0.91
*
10.9
=
9.9
228
2003,
4th
highest
Peak
Daily
PM2.5
0.91
*
10.6
=
9.6
234
2003,
5th
highest
Peak
Daily
PM2.5
0.91
*
9.3
=
8.5
237
Theodore
Roosevelt
NP,
EI
>=
250tons
SO2
or
NOX,
annual
tons.
Theodore
Roosevelt
NP,
NonEGU
BART
Eligible,
annual
tons.
Theodore
Roosevelt
NP,
EGU
Bart
Eligible,
annual
tons.
Sum
BART
SO2
237,527
0
26,313
26,313
NOx
85,099
0
10,733
10,733
Sum
322,626
0
37,046
37,046
Yellowstone
NP
Yellowstone
NP
Roll­
Back
Analysis,
Facilities
only
with
greater
than
250
annual
tons.

95,101
 
[(
SO2
*
0.9)
+
(
NOx
*
0.5)]
Estimate
of
air
quality
impact
=
(
Air
Quality
Indicator)
x
95,101
95,101
 
[(
0
*
0.9)
+
(
433
*
0.5)]
Estimated
impact
=
(
Air
Quality
Indicator)
x
95,101
Estimated
impact
=
(
Air
Quality
Indicator)
x
0.998
 
The
Roll­
Back
Factor
for
Yellowstone
NP
Yellowstone
NP,
Estimated
Annual
Air
Quality
Impacts
Tmass
Bext
Deciview
2003,
1
yr
annual
average
0.99
*
4.7
=
4.7
0.99
*
11.7
=
11.6
From
7.7
to
7.7
2001_
2003,
3
yr
annual
average
0.99
*
4.9
=
4.9
0.99
*
12.8
=
12.8
From
8.2
to
8.2
Yellowstone
NP,
Estimated
Daily
Air
Quality
Impacts
Year,
Daily
unit
Air
Quality
Indicator
Est.
Air
Quality
Impact
Day
of
year
impact
occurred
2003,
1st
highest
Peak
Daily
Extinction
0.998
*
34.8
=
34.7
246
2003,
2nd
highest
Peak
Daily
Extinction
0.998
*
30.4
=
30.3
237
2003,
3rd
highest
Peak
Daily
Extinction
0.998
*
29.6
=
29.5
204
2003,
4th
highest
Peak
Daily
Extinction
0.998
*
27.8
=
27.7
213
2003,
5th
highest
Peak
Daily
Extinction
0.998
*
25.1
=
25.0
201
2003,
1st
highest
Peak
Daily
SO4
0.998
*
1.8
=
1.8
228
2003,
2nd
highest
Peak
Daily
SO4
0.998
*
1.5
=
1.5
126
2003,
3rd
highest
Peak
Daily
SO4
0.998
*
1.3
=
1.3
225
2003,
4th
highest
Peak
Daily
SO4
0.998
*
1.2
=
1.2
222
2003,
5th
highest
Peak
Daily
SO4
0.998
*
1.2
=
1.2
273
2003,
1st
highest
Peak
Daily
NO3
0.998
*
1.2
=
1.2
42
2003,
2nd
highest
Peak
Daily
NO3
0.998
*
1.2
=
1.2
336
2003,
3rd
highest
Peak
Daily
NO3
0.998
*
0.9
=
0.9
126
2003,
4th
highest
Peak
Daily
NO3
0.998
*
0.9
=
0.9
222
2003,
5th
highest
Peak
Daily
NO3
0.998
*
0.8
=
0.8
99
2003,
1st
highest
Peak
Daily
PM2.5
0.998
*
8.5
=
8.5
246
2003,
2nd
highest
Peak
Daily
PM2.5
0.998
*
7.2
=
7.2
204
2003,
3rd
highest
Peak
Daily
PM2.5
0.998
*
6.7
=
6.7
213
2003,
4th
highest
Peak
Daily
PM2.5
0.998
*
6.7
=
6.7
237
2003,
5th
highest
Peak
Daily
PM2.5
0.998
*
6.5
=
6.5
201
Yellowstone
NP,
EI
>=
250tons
SO2
or
NOX,
annual
tons.
Yellowstone
NP,
NonEGU
BART
Eligible,
annual
tons.
Yellowstone
NP,
EGU
Bart
Eligible,
annual
tons.
Sum
BART
SO2
66,597
0
0
0
NOx
28,504
433
0
433
Sum
95,101
433
0
433
