North
Carolina
Recommendation
for
Iredell
County
The
purpose
of
this
paper
is
to
discuss
the
rationale
for
recommending
the
townships
of
Coddle
Creek
and
Davidson
Townships
in
Iredell
County,
rather
than
the
entire
county,
as
nonattainment
for
the
8­
hour
ozone
standard.
This
is
not
an
MSA
county,
and
it
does
not
have
a
monitor
located
in
the
County.
The
northern
portion
of
the
county
is
rural.

 
First,
this
is
a
high
commuter
county
into
the
Charlotte
area
along
the
I­
77
corridor.
Based
on
1997
emissions
inventories,
Iredell
County
has
44.29
tons
per
day
of
NOx
(
state
total
is
2529
tons
per
day)
and
the
county
has
28.13
tons
per
day
of
VOC
(
state
total
is
1842
tons
per
day
 
anthropogenic
only).
Mobile
sources
represent
a
major
NOx
source
in
Iredell
County
(
27.35
tons
from
Highway
and
6.80
tons
from
Nonroad).
This
represents
77.1
percent
of
Iredell
County's
total
NOx
emissions
per
day
(
34.15
tons
of
NOx
from
nonroad
and
highway
out
of
the
county
total
of
44.29
tons
NOx
per
day).
In
July
1,
2003
Iredell
County
began
implementing
an
I/
M
program
that
requires
OBD
testing
for
model
year
1996
and
newer
cars.
Expansion
of
this
program
has
or
will
be
phased
in
neighboring
counties
in
the
Charlotte
area
by
January
1,
2004.
These
counties
include
Catawba,
Davidson,
Iredell,
Rowan,
Lincoln,
Stanley
and
Union.
Combined
Federal
and
state
control
programs
will
address
these
emissions
including
the
introduction
of
low
sulfur
gasoline,
which
will
be
required
statewide.
 
Second,
traffic
patterns
for
Iredell
County
is
4,579,180
Daily
VMT;
however,
the
2000
Census
data
shows
Iredell
County
contributing
only
2
percent
of
the
commuters
who
drive
in
to
Mecklenburg
County
to
work
each
day,
or
about
9,604
people.
Iredell
ranks
number
5
in
the
commuting
counties
into
Mecklenburg
and
there
is
a
substantial
drop
after
Cabarrus
County
which
ranks
number
4.
Approximately
22,693
residents
of
Cabarrus
County
drive
into
Mecklenburg
County
to
work
each
day
as
compared
to
Iredell
County's
9,604.
 
Third,
Iredell
County
does
not
have
a
monitor
located
in
it
and
the
nearest
monitor
is
in
neighboring
Rowan
County
(
Southeast
of
Iredell).
Enochville
monitor
has
a
current
design
value
(
DVC)
of
0.099
ppm
(
based
on
years
2001­
2003).
Projected
8­
Hour
modeling
results
show
the
Enochville
monitor
with
a
future
design
value
(
DVF)
of
0.090
ppm
in
2007.
On
days
this
monitor
has
the
highest
readings,
the
winds
are
generally
out
of
the
southwest,
indicating
that
the
emissions
from
southern
Iredell
County
are
not
likely
to
contribute
to
the
Enochville
monitor's
high
ozone
levels.
The
only
major
point
sources
to
control
for
NOx
in
Iredell
County
is
the
Transco
Natural
Gas
Pumping
Station.
Also
the
Duke
Energy's
Marshall
facility
located
in
neighboring
Catawba
County
will
have
less
regional
impact
because
of
the
NOx
SIP
call
and
the
Clean
Smokestacks
Act.
 
Fourth,
the
nonattainment
recommendations
for
Iredell
reflect
consideration
of
Population
Density
from
the
2000
Census
as
it
show
the
rural
nature
of
northern
Iredell
County.
Of
the
122,660
people
living
in
Iredell
County,
39,885
people
reside
in
the
two
townships
recommended
as
nonattainment,
which
is
32.5
percent
of
the
county
populous.
The
northern
portion
has
a
low
population
density,
with
2
tracts
containing
50­
100
people
per
square
mile,
and
6
tracts
with
100­
250
people
per
square
mile.
The
northern
portion
also
includes
Statesville,
where
I­
77
and
I­
40
intersect,
with
1
tract
containing
250­
500
people
per
square
mile,
and
5
small
tracts
with
500­
1500
people
per
square
mile.
 
In
conclusion,
North
Carolina
believes
this
is
an
appropriate
boundary
for
a
county
that
is
not
in
the
MSA
and
does
not
have
a
monitor.
North
Carolina
believes
that
the
majority
of
the
commuters
along
the
I­
77
corridor
are
captured
in
the
nonattainment
recommendation.
Further,
the
emission
sources
in
Iredell
County
are
either
already
controlled
or
will
be
controlled
under
State
or
Federal
regulations.
