PM2.5
Implementation
Plan
(
New
Source
Review
8/
22/
05)
FHWA
Comments
08/
29/
05
NSR
Preamble
 
Page
5;
under
"
Significant
Emissions
Rate"
for
VOC
and
ammonia
states
that
it
will
be
determined
by
the
SIP.
However,
what
about
the
case
where
the
State
or
EPA
finds
that
VOCs
and/
or
ammonia
are
significant
contributors
prior
to
the
SIP?

 
Page
13;
states
"
Thus,
a
State
could
exempt
NOx
from
its
PM2.5
NSR
program
in
a
specific
area
by
demonstrating
that
NOx
emissions
from
stationary
sources
in
that
area
are
not
a
significant
contributor
to
that
area=
s
ambient
PM2.5
concentrations
and
the
area
is
not
in
a
State
identified
by
EPA
as
a
source
of
a
PM2.5
interstate
transport
problem."
However,
to
be
consistent
with
the
approach
under
transportation
conformity
that
assumes
NOx
to
be
significant,
this
preamble
language
should
be
revised
to
clarify
that
the
State
could
not
make
this
determination
alone,
but
that
the
State
AND
EPA
would
have
to
make
this
finding.

 
Page
13;
states
"
EPA
does
not
believe
that
this
is
likely
to
add
a
major
burden
to
sources
as
NOx
is
already
a
regulated
NSR
pollutant.
This
is
because
NOx
is
an
identified
precursor
for
the
ozone
NAAQS
and
an
indicator
for
the
NO2
NAAQS."
Does
this
conclusion
account
for
the
fact
that
ozone
is
a
summer
problem,
whereas
PM­
2.5
may
be
a
year­
round
pollutant,
or
that
the
PM­
2.5
NOx
may
be
a
winter
problem?

 
Page
26;
states
"
A
necessary
component
of
our
approach
to
NSR
applicability
for
ammonia
is
that
those
States
who
determine
in
their
SIPs
that
control
of
ammonia
is
necessary
will
set
the
significant
emissions
rate
for
ammonia
based
on
the
information
presented
in
each
attainment
demonstration."
This
seems
to
imply
that
a
rate
could
not
be
set
until
the
SIP
is
submitted.
However,
pages
14­
15
seems
to
allow
States
to
find
that
ammonia
is
significant,
prior
to
the
SIP,
consistent
with
the
transportation
conformity
rule.
If
the
State
determines
that
ammonia
is
significant
prior
to
the
SIP,
what
should
the
significant
emissions
rate
be?

 
Page
44;
states
"
VOCs
would
be
subject
to
the
offset
requirement
if
we
designated
this
regulated
NSR
pollutant
as
a
PM2.5
precursor"
and
is
silent
regarding
ammonia.
However,
this
seems
to
be
inconsistent
with
the
following
sentence,
the
section
on
what
precursors
are
applicable
to
NSR,
and
the
transportation
conformity
rule.
The
section
should
more
clearly
state
that
offsets
would
be
required
for
NOx
and
SO2
unless
the
State
AND
EPA
find
that
they
are
not
significant
contributors
to
the
PM2.5
problem,
and
that
offsets
would
only
be
required
for
VOCs
and/
or
ammonia
if
the
State
or
EPA
find
that
they
are
a
significant
contributor
to
the
PM2.5
air
quality
problem.
 
Page
63;
states
"
Because
of
the
challenges
posed
by
the
SIP
development
period,
EPA
is
considering
whether
NSR
applicability
to
precursors
should
be
stayed
for
one
or
more
precursors
during
the
SIP
development
period."
Staying
the
applicability
of
precursors
during
the
SIP
development
period
would
be
inconsistent
with
the
approach
to
on­
road
sources
and
transportation
conformity.
If
precursors
are
a
concern
other
sources,
then
they
should
not
be
stayed
only
for
NSR.

NSR
Regulatory
Text
 
Page
3;
states
" 
unless
it
is
demonstrated
that
emissions
of
nitrogen
oxides
from
stationary
sources
in
a
specific
area
are
not
a
significant
contributor
to
that
area=
s
ambient
PM2.5
concentrations "
The
regulation
should
more
clearly
state
that
both
the
State
AND
EPA
must
find
that
NOx
emissions
are
not
a
significant
contributor.
And,
in
the
following
provision,
the
regulation
should
more
clearly
state
that
either
the
State
OR
EPA
could
find
that
VOCs
and/
or
ammonia
are
significant.

 
Page
9;
what
about
ammonia
in
attainment
and
unclassifiable
areas?

 
Page
13;
see
comment
about
regarding
page
3
and
findings
by
the
State
and/
or
EPA
regarding
significance
findings.

 
Page
17­
18;
what
about
ammonia
in
attainment
and
unclassifiable
areas?
