Document ID: EPA-HQ-OAR-2003-0083-1368
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2004-03-19T05:00Z

North
Carolina
Recommendation
for
Caldwell
County
The
purpose
of
this
paper
is
to
discuss
the
rationale
for
recommending
the
metropolitan
planning
boundary
in
Caldwell
County,
along
with
parts
of
Alexander,
Catawba,
and
Burke,
rather
than
the
entire
Metropolitan
Statistical
Area
as
nonattainment
for
the
8­
hour
ozone
standard.

 
This
area
has
a
marginal
8­
hour
ozone
problem,
with
the
2000­
2002
design
values
being
0.086
ppm
at
the
Lenoir
site
(
Caldwell
County)
and
0.091
ppm
at
the
Taylorsville
site.
The
2001­
2003
design
values
are
0.084
for
the
Lenoir
site
and
0.088
ppm
for
the
Taylorsville
site.
 
A
back
trajectory
wind
analysis
suggests
that
these
sites
are
impacted
by
transport
from
the
west
and
northwest,
and
that
pollution
comes
over
the
mountains
and
mixes
down
into
the
valleys
where
the
monitors
are
located.
There
are
also
a
number
of
days
when
both
Charlotte
and
the
Triad
are
having
impacts
on
these
sites.
For
these
reasons,
we
recommend
a
smaller
area
than
the
full
MSA.
 
Caldwell
County
has
the
second
smallest
population
of
the
four
MSA
counties,
with
77,415
people
living
in
the
county.
This
compares
to
a
population
of
33,063
for
Alexander
County,
89,148
for
Burke
County,
and
141,685
for
Catawba
County.
The
MPO
Planning
boundary
captures
257,572
people,
of
the
total
341,851
people
living
in
the
four
county
MSA,
or
75
percent
of
the
population
represented
in
the
MPO
Planning
boundary.
 
Caldwell
County
has
9.37
tons
per
day
of
NOx
and
the
county
has
39.19
tons
per
day
of
VOC,
and
represents
the
second
lowest
contributor
to
NOx
and
VOC
emissions
of
the
four
MSA
counties.
The
major
source
sector
for
NOx
emissions
in
Caldwell
County
is
mobile
sources,
contributing
5.36
tons
per
day
based
on
1997
emission
inventories.
The
mobile
emissions
will
be
reduced
by
the
Tier
2
engine
standards,
low
sulfur
gasoline,
diesel
engine
standards,
low
sulfur
diesel,
and
the
I/
M
program.
 
Based
on
the
most
recent
modeling
analysis,
North
Carolina
expects
this
region
to
attain
by
2007.
 
In
conclusion,
the
areas
of
Caldwell
County
that
are
not
included
in
the
proposed
designation
are
extremely
rural
(
typical
population
density
is
0­
50
and
50­
100
persons
per
square
mile).
Caldwell
County
is
clearly
a
"
downwind"
area
from
the
emissions
of
any
consequence
and
the
Lenoir
monitor
was
sited
to
act
as
a
downwind
monitor
for
the
upwind
source
area
that
North
Carolina
is
recommending
for
nonattainment.
Caldwell
County's
emissions
are
expected
to
decrease
in
the
future
as
Federal
and
state
mobile
source
measures
take
effect.