Document ID: EPA-HQ-OAR-2003-0083-1362
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2004-03-19T05:00Z

North
Carolina
Recommendation
for
Cabarrus
County
The
purpose
of
this
paper
is
to
discuss
the
rationale
for
recommending
less
than
the
entire
Cabarrus
County
as
nonattainment
for
the
8­
hour
ozone
standard,
which
is
part
of
the
Charlotte/
Gastonia/
Rock
Hill
Metropolitan
Statistical
Area
(
MSA).
This
MSA
County
does
not
have
a
monitor
located
in
it.
The
recommendation
includes
the
entire
county
except
for
three
small
townships
in
the
northeastern
corner
of
the
county
located
in
1
Census
tract
containing
50­
100
people
per
square
mile.
These
townships
not
recommended
to
be
designated
nonattainment
are
Rimertown,
Gold
Hill
and
Mount
Pleasant.

 
First,
the
nearest
monitors
to
Cabarrus
County
are
located
in
neighboring
counties
of
Rowan
(
Enochville
monitor)
and
Mecklenburg
(
County
Line).
Recent
8­
hour
modeling
for
2007
show
that
Enochville's
Design
Value
Future
(
DVF)
is
lowered
9
ppm
from
the
Design
Value
Current
(
DVC)
of
0.099
for
the
three
years
spanning
2001­
2003.
County
Line
monitor's
DVF
is
lowered
6
ppm
to
0.090
over
the
same
parameters.
This
is
a
significant
reduction
and
ozone
levels
realized
as
the
state
and
federal
control
measures
are
implemented.
 
Second,
there
are
few
major
point
sources
within
the
county
to
control
(
only
2.44
tons
per
day
of
NOx
come
from
point
sources)
and
highway
mobile
is
the
primary
NOx
source
in
Cabarrus
County
(
12.93
tons
per
day
out
of
a
total
of
24.35
tons)
making
up
more
than
53.1
percent
of
the
counties
daily
NOx
emissions.
Cabarrus
County
had
an
existing
I/
M
program
(
idle
only);
however,
the
newer
OBD
testing
for
newer
vehicles
was
introduced
in
July
1,
2002.
Several
neighboring
counties
have
or
will
phase
in
OBD
testing
by
January
1,
2004.
These
counties
include
Catawba,
Davidson,
Iredell,
Rowan,
Lincoln,
Stanley
and
Union.
 
Third,
census
population
density
and
the
extent
of
urbanization
in
Cabarrus
County
show
that
the
three
townships
recommended
to
be
attainment
only
represent
6.5
percent
of
all
residents
in
the
county
or
8,612
out
of
131,063
people.
The
northeastern
portion
of
Cabarrus
County
has
low
population
density,
with
1
tract
containing
50­
100
people
per
square
mile.
Also
Cabarrus
County
as
part
of
the
Charlotte/
Gastonia/
Rock
Hill
MSA
ranks
number
4
out
of
5
counties
with
regard
to
the
number
of
people
commuting
into
the
urbanized
county
of
Mecklenburg.
Only
4.8
percent
of
Cabarrus
residents
commute
into
Mecklenburg
County
daily.
 
In
conclusion,
Cabarrus
County
has
the
very
rural
Census
tract
consisting
of
3
townships
in
the
northeastern
corner
of
the
county
with
population
densities
of
50­
100
people
per
square
mile.
North
Carolina
believes
that
the
Federal
engine
standards
and
fuel
programs,
as
well
as
the
new
inspection
and
maintenance
program
that
requires
on­
board
diagnostic
testing
in
48
counties
(
OBD
phased
in
between
2002
and
2006)
will
not
only
control
mobile
source
NOx
emissions
in
these
counties
but
will
have
a
beneficial
impact
on
rural
areas
within
counties
and
neighboring
counties.