1Section
182(
b)(
3)
specifies
that
EPA
would
approve
any
request
from
a
State
to
reclassify
to
a
higher
classification.
Technical
Support
Document
for
Cass
County,
Michigan
September
2004
Chapter
1.0
Summary
On
July
15,
2004
Steven
Chester,
Michigan
Department
of
Environmental
Quality
(
MDEQ)
Director
and
Governor's
designee,
submitted
a
request
to
reclassify
Cass
County
from
Moderate
ozone
nonattainment
to
Marginal
ozone
nonattainment.
A
subsequent
submittal
supplying
additional
information
was
made
on
August
20,
2004.
The
petition
is
based
on
the
area's
Moderate
design
value
of
93
ppb
being
within
5%
of
the
maximum
Marginal
design
value
of
91
ppb
as
allowed
by
the
Clean
Air
Act.

EPA
has
reviewed
this
request
and
believes
the
area
should
be
reclassified
as
Marginal
ozone
nonattainment.

2.0
Introduction
This
section
describes
the
statutory
provisions
and
EPA
guidance
regarding
reclassification
of
ozone
nonattainment
areas.
Sections
181(
a)(
4)
and
182(
b)(
3)
of
the
Clean
Air
Act
provide
that
areas
may
be
reclassified
under
certain
circumstances.
This
technical
support
document
addresses
the
provisions
of
section
181(
a)(
4)
and
a
specific
request
for
reclassifications
received
by
the
State
of
Michigan.
The
EPA
has
not
received
any
requests
for
reclassification
under
section
182(
b)(
3)
for
the
8­
hour
ozone
standard.
1
Under
section
181(
a)(
4),
an
ozone
nonattainment
area
may
be
reclassified
"
if
an
area
classified
under
paragraph
(
1)
(
Table
1)
would
have
been
classified
in
another
category
if
the
design
value
in
the
area
were
5
percent
greater
or
5
percent
less
than
the
level
on
which
such
classification
was
based."
In
the
April
30,
2004
notice,
we
indicated
that
an
area
with
a
moderate
design
value
of
96
ppb
(
or
less)
would
be
eligible
to
request
a
bump
down
because
five
percent
less
than
96
ppb
is
91
ppb,
a
marginal
design
value.

The
EPA
previously
described
criteria
to
implement
the
section
181(
a)(
4)
provisions
in
a
final
rule
designating
and
classifying
areas
published
on
November
6,
1991
(
56
FR
56698).
As
stated
in
that
notice,
the
provisions
of
section
181(
a)(
4)
set
out
general
­
2
­

criteria
and
grant
the
Administrator
broad
discretion
in
making
or
determining
not
to
make,
a
reclassification.
As
part
of
the
1991
action,
EPA
developed
more
specific
criteria
to
evaluate
whether
it
is
appropriate
to
reclassify
a
particular
area.
The
EPA
also
described
these
criteria
in
the
April
30,
2004
final
rule.
The
general
and
specific
criteria
are
as
follows:

General:
The
EPA
may
consider
the
number
of
exceedances
of
the
national
primary
ambient
air
quality
standard
for
ozone
in
the
area,
the
level
of
pollution
transport
between
the
area
and
other
affected
areas,
including
both
intrastate
and
interstate
transport,
and
the
mix
of
sources
and
air
pollutants
in
the
area.

Request
by
State:
The
EPA
does
not
intend
to
exercise
its
authority
to
bump
down
areas
on
EPA's
own
initiative.
Rather,
EPA
intends
to
rely
on
the
State
to
submit
a
request
for
a
bump
down.
A
Tribe
may
also
submit
such
a
request
and,
in
the
case
of
a
multi­
state
nonattainment
area,
all
affected
States
must
submit
the
reclassification
request.

Discontinuity:
A
five
percent
reclassification
must
not
result
in
an
illogical
or
excessive
discontinuity
relative
to
surrounding
areas.
In
particular,
in
light
of
the
areawide
nature
of
ozone
formation,
a
reclassification
should
not
create
a
"
donut
hole"
where
an
area
of
one
classification
is
surrounded
by
areas
of
higher
classification.

Attainment:
Evidence
should
be
available
that
the
proposed
area
would
be
able
to
attain
by
the
earlier
date
specified
by
the
lower
classification
in
the
case
of
a
bump
down.

Emissions
reductions:
Evidence
should
be
available
that
the
area
would
be
very
likely
to
achieve
the
appropriate
total
percent
emission
reduction
necessary
in
order
to
attain
in
the
shorter
time
period
for
a
bump
down.

Trends:
Near­
and
long­
term
trends
in
emissions
and
air
quality
should
support
a
reclassification.
Historical
air
quality
data
should
indicate
substantial
air
quality
improvement
for
a
bump
down.
Growth
projections
and
emission
trends
should
support
a
bump
down.
In
addition,
we
will
consider
whether
vehicle
miles
traveled
and
other
indicators
of
emissions
are
increasing
at
higher
than
normal
rates.

Years
of
data:
For
the
8­
hour
ozone
standard,
the
2001­
2003
­
3
­

period
is
central
to
determining
classification.
Data
from
2004
may
be
used
to
corroborate
a
bump
down
request
but
should
not
be
the
sole
foundation
for
the
bump
down
request.

Limitations
on
Bump
Downs
An
area
may
only
be
reclassified
to
the
next
lower
classification.
An
area
cannot
present
data
from
other
years
as
justification
to
be
reclassified
to
an
even
lower
classification.
In
addition,
section
181(
a)(
4)
does
not
permit
moving
areas
from
subpart
2
into
subpart
1.

In
1991,
EPA
approved
reclassifications
when
the
area
met
the
first
requirement
(
a
request
by
the
State
to
EPA)
and
at
least
some
of
the
other
criteria
and
did
not
violate
any
of
the
criteria
(
emissions,
reductions,
trends,
etc.).
In
our
April
30,
2004
final
rule
on
designations
and
classifications,
we
stated
our
intention
to
use
this
method
and
these
criteria
once
again
to
evaluate
reclassification
requests
under
section
181(
a)(
4),
with
minor
changes
described
in
that
notice.
In
that
notice
we
also
described
how
we
applied
these
criteria
in
1991.
For
additional
information,
see
section
5,
"
Areas
requesting
a
5%
downshift
per
§
181(
a)(
4)
and
EPA's
response
to
those
requests,"
of
the
Technical
Support
Document,
October
1991,
for
the
1991
rule.
[
Docket
A­
90­
42A.]

EPA
is
not
basing
this
reclassification
determination
on
consideration
of
whether
the
nonattainment
area
being
reclassified
does
or
does
not
cause
any
pollution
transport.
The
EPA
is
presently
addressing
ozone
pollution
transport
issues
throughout
the
eastern
part
of
the
United
States
under
other
Clean
Air
Act
provisions.
Specifically,
EPA
has
proposed
a
determination
that
emissions
from
certain
states
contribute
significantly
to
downwind
nonattainment
for
ozone
under
CAA
section
110(
a)(
2)(
D)
through
the
Clean
Air
Interstate
Rule
(
CAIR).
The
CAIR
proposal,
published
in
a
Federal
Register
notice
dated
January
30,
2004,
would
require
upwind
States
to
eliminate
emissions
that
contribute
significantly
to
nonattainment
in
downwind
States.
69
Fed.
Reg.
454566.
The
EPA
previously
issued
the
NOx
SIP
call
(
63
FR
57356)
to
address
interstate
ozone
transport.
In
the
event
of
any
intrastate
transport
issue,
states
have
the
obligation
to
develop
attainment
SIPs
for
each
area
that
show
timely
attainment,
and
can
address
any
intrastate
transport
issues
in
that
context.

The
April
30,
2004
notice
invited
States
to
submit
the
reclassification
requests
within
30
days
of
the
effective
date
of
the
designations
and
classifications.
The
effective
date
was
June
15
which
means
that
reclassification
requests
were
to
be
­
4
­

submitted
by
July
15,
2004.
This
relatively
short
time
frame
is
necessary
because
section
181(
a)(
4)
only
authorizes
the
Administrator
to
make
such
reclassifications
within
90
days
after
the
initial
classification,
September
15,
2004.

3.0
Background
Cass
County
is
highly
impacted
by
transport
due
to
the
Lake
Michigan
ozone
phenomenon.
Cass
County
has
low
population
and
no
major
sources.
EPA
designated
this
area
as
Moderate
due
to
high
8­
hour
values
(
design
value
is
93
ppb)
and
1­
hour
values
(
122
ppb).

4.0
Reclassification
Request
by
State
The
State
argues
that
Cass
County
should
receive
a
reclassification
from
Moderate
to
Marginal.
The
demonstration
is
based
on
modeling
showing
earlier
attainment
(
2007),
identification
of
the
ozone
transport
problem
in
the
area,
and
a
demonstration
of
less
than
one
percent
of
contribution
from
local
sources.

5.0
EPA
Review
of
the
Reclassification
Request
5.1
Request
by
State
The
request
was
submitted
by
Steven
Chester,
Director
of
Michigan
Department
of
Environmental
Quality.
The
MDEQ
Director
is
the
Governor's
designee.

5.2
Discontinuity
If
Cass
County
is
reclassified
from
Moderate
to
Marginal,
this
will
not
result
in
a
discontinuity.
All
of
the
counties
immediately
bordering
Cass
County
are
either
designated
as
attainment
or
are
Subpart
1
nonattainment.

5.3
Attainment
The
Lake
Michigan
Air
Directors
Consortium
(
LADCo)
used
modeling
results
performed
to
support
the
1­
hour
ozone
attainment
demonstration
for
the
Lake
Michigan
area
and
applied
8­
hour
ozone
metrics.
This
modeling
conducted
by
LADCo
indicates
that
Cass
County
will
be
in
attainment
(
81
ppb)
in
2007.
However,
as
noted
in
Michigan's
petition,
the
LADCO
subregional
modeling
was
completed
in
2001
and
designed
to
assess
1­
hour
ozone
and,
as
such,
there
are
some
limitations
with
using
it
to
assess
8­
hour
ozone.
On
the
other
hand,
it
should
be
noted
that
three
of
the
­
5
­

2Engine
manufacturers
will
have
flexibility
to
meet
the
new
standards
through
a
phase­
in
approach
between
2007
and
2010.
The
fuel
provision
will
go
into
effect
in
June
2006
and
will
be
phased­
in
through
2009.
four
modeled
episodes
are
representative
periods
for
high
8­
hour
ozone
and
basecase
model
performance
for
8­
hour
ozone
was
found
to
be
as
good
as
(
or
better
than)
that
for
1­
hour
ozone
(
page
7
of
the
IDEM
&
LADCo
July
2004
"
Photochemical
Modeling
Analysis
of
8­
Hour
Ozone
for
LaPorte
County").
Since
this
modeling
was
performed
before
the
Heavy
Duty
Engine
rule
was
proposed,
it
does
not
reflect
emission
reductions
from
that
national
program.
2
Use
of
a
more
recent
emission
inventory
and
base
design
value
would
likely
result
in
lower
predicted
concentrations.

Additional,
regional
scale,
modeling
from
the
January
2004
proposed
Clean
Air
Interstate
Rule
however,
indicates
that
the
area
will
be
in
attainment
(
83
ppb)
by
2010.
The
CAIR
modeling,
however,
was
not
designed
to
provide
results
for
years
prior
to
2010.

5.4
Emissions
Reductions
Because
this
area
is
so
heavily
impacted
by
transported
pollution
from
upwind
areas,
it
would
be
difficult
to
show
that
reductions
from
the
area
will
help
to
achieve
the
area's
earlier
attainment
date.
It
can
be
expected
that
ozone
values
will
continue
to
decrease
due
to
the
implementation
of
various
rules
such
as
the
NOx
SIP
Call,
Tier
II/
Low
Sulfur,
Heavy
Duty
Diesel
Engine
standards/
low
sulfur
diesel,
and
other
national
rules.
In
addition,
implementation
of
emission
reductions
contained
in
1­
hour
ozone
attainment
plans
in
the
Lake
Michigan
area
will
further
reduce
emissions.

Other
voluntary
measures
being
implemented
in
the
Lake
Michigan
area
include:

°
Schoolbus,
nonroad
vehicle
and
garbage
truck
diesel
retrofit
programs
°
Alternative
fuel
fleets
°
Gas
can
replacement
programs
°
Lawmower
buyback
programs
°
Educational
outreach
programs
and
ozone
action
days
5.5
Trends
­
6
­

3The
ozone
values
for
the
2004
ozone
season
through
September
1
and
are
preliminary.
The
4th
highest
values
for
ozone
from
2002,
2003
and
20043
show
a
decreasing
trend
at
103
ppb,
89
ppb
and
74
ppb,
respectively.
Further,
it
can
be
expected
that
ozone
values
will
continue
at
these
lower
levels
due
to
the
implementation
of
various
rules
such
as
the
NOx
SIP
Call,
Tier
II/
Low
Sulfur,
Heavy
Duty
Diesel
Engine
standards/
low
sulfur
diesel,
and
other
national
rules.
In
addition,
implementation
of
emission
reductions
contained
in
1­
hour
ozone
attainment
plans
in
the
Lake
Michigan
area
will
further
reduce
emissions
and
improve
air
quality.

5.6
Years
of
Data
The
design
value
being
used
a
2001­
2003
value
and
it
is
93
ppb.

5.7
Additional
Information
The
CAMx
(
version
4.03),
with
the
OSAT
technology,
was
used
in
this
analysis
to
determine
the
geographic
source
(
i.
e.,
Chicago)
contribution
of
ozone
precursors
and
source
emissions
type
(
i.
e.,
on­
road
mobile)
contribution
at
specific
locations
such
as
the
Cassopolis
monitor.
Based
on
that
analysis,
less
than
one
percent
of
the
ozone
recorded
at
the
Cassopolis
monitor
can
be
attributed
to
local
(
i.
e.,
Cass
Co.
plus
St.
Joseph
Co.)
emissions.

5.8
Conclusions
In
summary,
the
following
factors
support
the
request
for
reclassification
to
marginal
for
Cass
County:
the
design
value
of
93
ppb
meets
our
criteria
to
qualify
for
consideration
of
bump
down,
local
and
regional
modeling
analyses
indicate
air
quality
will
be
improving
over
the
next
several
years
and
support
attainment
by
the
marginal
area
attainment
date,
a
short
term
trends
analysis
shows
ozone
values
decreasing,
and
additional
reductions
from
regional
and
national
regulations
will
continue
this
trend
in
lowering
ambient
ozone
values.

5.9
EPA
Action
The
reclassification
request
for
Cass
County
meets
all
of
the
criteria
(
request,
discontinuity,
attainment,
emission
reductions,
trends,
and
data)
EPA
established
(
69
FR
23863).
Therefore,
EPA
is
approving
the
reclassification
request
for
Cass
County.
­
7
­

6.0
Additional
Information
Additional
information
regarding
the
bump
down
request
for
this
area
is
contained
in
the
docket
for
this
action.
This
information
includes
the
State
request,
supporting
documents,
and
other
necessary
material.
