Document ID: EPA-HQ-OAR-2003-0083-1891
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2004-09-10T04:00Z

Lancaster
"
Bump­
Down"
Request
Additional
Information
August
23,
2004
This
enclosure
includes
additional
information
concerning
the
Pennsylvanian
Department
of
Environmental
Protection's
(
PA
DEP's)
request
to
have
Lancaster
County
reclassified
as
a
marginal
eight­
hour
ozone
non­
attainment
area.
PA
DEP's
original
"
bump­
down"
request
was
submitted
to
U.
S.
Environmental
Protection
Agency
(
EPA)
Region
III
on
July
9,
2004.

Information
in
this
submission
includes
zero­
out
CALGRID
model
results
for
Lancaster
County
and
the
entire
Commonwealth
of
Pennsylvania.
It
also
includes
a
brief
summary
of
emission
controls
enacted
in
Lancaster
County
by
the
Commonwealth
of
Pennsylvania
(
see
attached
table).

Summary
of
CALGRID
Runs
CALGRID
is
a
PC­
based
ozone­
modeling
system
developed
by
EarthTech
for
the
Ozone
Transport
Commissioin
(
OTC).
The
model
was
designed
as
a
tool
to
help
the
OTC
assess
different
emission
control
strategies.
PA
DEP
will
attempt
to
produce
additional
CALGID
documentation.

Zero­
out
runs
were
run
with
CALGRID
to
estimate
ozone
transport
from
Lancaster
County.
The
model
uses
meteorological
data
from
one
of
the
OTAG
episodes;
July
5­
15,
1995.
Ozone
concentrations
during
this
episode
were
well
above
the
eight­
hour
standard
throughout
the
northeast.
Anthropogenic
emissions
from
Lancaster
County
were
set
to
zero.
Emissions
were
based
on
the
2010
CAA
emission
files
developed
by
EPA
for
its
Clear
Skies
modeling.
For
comparison,
a
zero­
out
CALGRID
run
was
done
for
the
entire
Commonwealth
of
Pennsylvania.
The
results
of
these
runs
are
summarized
in
Figure
1
and
Figure
2.

CALGRID
suggests
ozone
transport
from
Lancaster
County
is
not
significant
compared
with
transport
from
the
entire
Commonwealth
of
Pennsylvania.
The
model
indicates
emissions
from
Lancaster
County
contribute
to
a
maximum
increase
of
nine
parts
per
billion
(
ppb)
in
neighboring
Chester
County
over
the
entire
episode.
In
contrast,
CALGRID
indicates
the
Commonwealth
of
Pennsylvania
contributes
up
to
45
ppb
in
regions
of
New
Jersey
and
New
England.
Therefore,
CALGRID
suggests
Lancaster
County's
emissions
contribute
to
minimal
ozone
generation,
which
is
largely
confined
to
areas
inside
the
Commonwealth
of
Pennsylvania.
Figure
1.
Figure
2.