­­­
Forwarded
by
John
Silvasi/
RTP/
USEPA/
US
on
08/
11/
2005
08:
32
AM
­­­­­

John
Silvasi/
RTP/
USEPA/
US
08/
10/
2005
02:
35
PM
T
o
Art
Fraas,
Amy
Flynn
c
c
Tom
Helms,
Lydia
Wegman/
RTP/
USEPA/
US@
EPA,
Rich
Damberg/
RTP/
USEPA/
US@
EPA,
Jim
Ketcham­
Colwill,
Sara
Schneeberg,
Jan
Tierney/
DC/
USEPA/
US@
EP
A,
Robert
Meyers/
DC/
USEPA/
US@
EP
A,
Geoffrey
Wilcox/
DC/
USEPA/
US@
EP
A
S
u
b
j
e
c
t
Revised
RACT
sections­­
8­
hr
O3
NAAQS
implementation
rule
Hi,
Art
&
Amy
The
revisions
reflect
your
faxed
comments
of
8/
8/
05,
but
we
have
added
a
bit
of
additional
text
in
response
to
your
changes,
which
we
can
discuss
if
you
need.

With
regard
to
the
relationship
between
MACT,
LAER
and
BACT
to
RACT,
we
do
not
believe
we
can
provide
a
blanket
statement
that
just
because
a
source
meets
these
other
standards
that
they
in
all
cases
meet
RACT.
There
are
a
number
of
considerations,
including
the
ones
mentioned
below
in
bullets.
Background
information
on
factors
affecting
whether
a
prior
control
determination
results
in
RACT­
level
control
Sources
subject
to
8­
hour
ozone
nonattainment
RACT
requirements
may
previously
have
been
subject
to
MACT
for
toxic
pollutants
or
to
BACT
(
best
available
control
technology
for
large
new
or
modified
sources
in
attainment
areas
for
a
pollutant),
LAER
(
lowest
achievable
emissions
rate
for
large
new
or
modified
emissions
sources
in
nonattainment
area
for
a
particular
pollutant),
or
settlements
of
of
lawsuits
regarding
a
source's
compliance
with
new
source
requirements
in
nonattainment
areas
(
NSR)
or
attainment
areas
(
PSD).
These
determinations
may
have
required
controls
that
are
as
stringent
or
more
stringent
than
the
RACT
level
of
control
for
8­
hour
ozone
precursors
(
VOC
or
NOx).
On
the
other
hand,
in
the
past
states
and
EPA
have
found
that
a
prior
control
determination
may
not
assure
RACT­
level
control
of
either
ozone
precursor
for
reasons
such
as
the
following:

°
The
prior
determination
may
have
focused
on
other
pollutants
and
program
purposes
and
therefore
may
not
have
required
any
control
of
VOC
or
NOx.

°
The
prior
determination
my
have
focused
on
other
pollutants
and
program
purposes,
and
may
have
resulted
in
some
limited
reduction
in
an
ozone
precursor
that
does
not
represent
RACT­
equivalent
control
(
e.
g.,
a
MACT
standard
that
allows
substitution
of
non­
HAP
VOCs
for
HAP
VOCs
may
not
result
in
significant
VOC
reduction).

°
The
prior
determination
may
have
involved
review
of
some,
but
not
all,
of
the
emission
points
subject
to
RACT.

°
Applicability
thresholds
for
the
prior
determination
may
have
been
higher
than
the
applicability
threshold
for
RACT
that
exists
in
the
nonattainment
area.

°
Costs
of
an
existing
control
technology
may
have
dropped
since
the
prior
determination.

°
Control
efficiency
of
an
existing
control
technology
may
have
significantly
increased
since
the
prior
determination.

°
New
control
technologies
may
have
become
available
since
the
prior
determination.

John
J.
Silvasi
Environmental
Engineer
Ozone
Policy
and
Strategies
Group
(
C539­
02)
Office
of
Air
Quality
Planning
and
Standards
U.
S.
Environmental
Protection
Agency
Research
Triangle
Park,
NC
27711
919­
541­
5666
(
v);
919­
541­
0824
(
fax)
silvasi.
john@
epa.
govPer
your
request
on
the
fax,
I'm
also
attaching
the
portion
of
our
draft
Response
to
Comment
document
dealing
with
the
issue
in
the
footnote
regarding
the
IPM
runs
for
CAIR.
Attached
is
a
redline
strikeout
comparison
of
the
RACT
portions
of
the
8­
hr
O3
rule
compared
with
a
modified
version
of
the
7/
19/
05
version
we
sent.
The
modifications
to
the
7/
19/
05
version
used
for
the
comparison
reflect
the
revisions
we
sent
you
on
8/
2
and
8/
3.
