Document ID: EPA-HQ-OAR-2003-0048-0122
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2004-02-26T05:00Z

UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
OFFICE
OF
AIR
QUALITY
PLANNING
AND
STANDARDS
EMISSION
STANDARDS
DIVISION
RESEARCH
TRIANGLE
PARK,
NC
27711
February
25,
2004
MEMORANDUM
SUBJECT:
Development
of
Lookup
Tables
for
the
Plywood
and
Composite
Wood
Products
(
PCWP)
Source
Category
FROM:
Scott
Jenkins,
Maria
Pimentel,
Dennis
Pagano
Risk
and
Exposure
Assessment
Group
(
C404­
01)

TO:
David
E.
Guinnup,
Leader
Risk
and
Exposure
Assessment
Group
(
C404­
01)

Introduction
The
purpose
of
this
memo
is
to
describe
the
development
of
a
risk­
based
approach
for
the
PCWP
source
category
by
which
a
facility
could
establish
whether
its
cancer
and
non­
cancer
risk
levels
could
be
considered
to
be
of
negligible
regulatory
concern.

Methodology
The
analysis
was
based
on
data
from
emissions
associated
with
the
production
of
medium
density
fiberboard
(
MDF),
particleboard,
hardboard,
fiberboard,
oriented
strand
board
(
OSB),
softwood
plywood
and
veneer,
and
engineered
wood
products
(
EWP).

Lookup
tables
were
developed
to
provide
facilities
with
a
method
for
determining
whether
they
are
low­
risk
based
on
their
site
specific
HAP
emission
rates
which
they
would
measure
and
compare
to
the
appropriate
values
in
the
tables.
Separate
tables
were
developed
for
cancer
and
chronic
noncancer
effects.
Because
the
lookup
tables
must
be
applicable
to
all
facilities
in
the
category,
each
with
different
meteorological
conditions,
the
EPA's
SCREEN3
(
ISAPI,
1995)
atmospheric
dispersion
model
was
utilized.

SCREEN3,
a
screening
level
Gaussian
dispersion
model
was
used
to
predict
worst­
case
1­
hour
concentrations
on
the
centerline
of
the
plume
downwind
from
a
source.
SCREEN3
models
a
single
stack
facility
which
adds
health­
protectiveness
to
our
tables
because
the
dispersion
inherent
in
the
spatial
separation
of
multiple
stacks
is
not
considered.
SCREEN3
calculated
the
ambient
concentration
per
g/
s
of
emissions
assuming
no
deposition
or
atmospheric
reactions.
Predicted
1­
hour
concentrations
from
SCREEN3
were
multiplied
by
0.08,
as
described
in
the
EPA
Air
Toxics
Risk
Assessment
Reference
Library,
to
generate
estimates
of
chronic
pollutant
concentration.
The
lookup
tables
did
not
consider
population
data,
facility
coordinates,
or
actual
facility
boundaries.
Therefore,
facilities
not
qualifying
as
low
risk
based
on
the
lookup
table
might
still
qualify
as
low
risk
based
on
a
site­
specific
assessment.
2
To
develop
the
lookup
table
for
HAP
with
carcinogenic
potential,
SCREEN3
model
runs
were
conducted
using
worst­
case
meteorology
defaults,
local
flat
terrain,
and
a
single­
stack
facility
with
parameters
representing
approximate
midpoint
conditions
across
the
PCWP
source
category:
stack
diameter
=
1.7
meters;
exit
velocity
=
15.4
meters
per
second;
and,
exit
gas
temperature
=
316.5
K.
We
assumed
emission
of
a
hypothetical
reference
HAP
with
a
URE
of
1
(

g/
m3)­
1.
The
emission
rate
of
this
hypothetical
HAP
resulting
in
a
maximum
cancer
risk
equal
to
1
in
1
million
was
entered
into
the
table
for
each
combination
of
stack
height
and
fenceline
distance
(
see
appendix
A).

To
develop
the
noncancer
lookup
table,
SCREEN3
model
runs
were
conducted
as
above
except
that
facility
parameters
were
made
more
health
protective
to
ensure
that
any
facilities
determined
to
be
low
risk
by
the
chronic
noncancer
lookup
table
would
also
be
low
risk
for
acute
noncancer
effects
(
see
results
below).
These
health
protective
facility
parameters
were:
stack
diameter
=
1.1
meters;
exit
gas
velocity
=
9.0
meters
per
second;
and,
exit
gas
temperature
=
293K.
We
assumed
emission
of
a
hypothetical
HAP
with
an
RfC
of
1

g/
m3.
The
emission
rate
of
this
hypothetical
HAP
resulting
in
a
maximum
non­
cancer
hazard
index
equal
to
1.0
was
entered
into
the
table
for
each
combination
of
stack
height
and
fenceline
distance
(
see
appendix
A).

Next,
we
determined
how
many
PCWP
facilities
might
qualify
as
low
risk
based
on
the
lookup
tables
we
developed.
For
this
analysis,
we
utilized
site­
specific
emissions
estimates
developed
for
each
individual
facility
in
the
source
category.
Emissions
and
HAP
selection
information
for
the
PCWP
source
category
can
be
found
in
the
memo
from
February
18,
2004
titled
"
Risk
assessment
for
the
final
maximum
achievable
control
technology
(
MACT)
rule
for
the
plywood
and
composite
wood
products
(
PCWP)
source
category"
from
Scott
Jenkins,
Maria
Pimentel,
and
Dennis
Pagano
to
Dave
Guinnup.
To
combine
emissions
of
different
HAP,
emission
rates
were
normalized
as
described
in
equations
1
(
carcinogens)
and
2
(
non­
carcinogens)
below
using
hypothetical
reference
compounds
with
a
URE
of
1
(

g/
m3)­
1
(
cancer)
and
an
RfC
of
1

g/
m3
(
noncancer).

NCER
=

(
ER
i
x
URE
i/
URE
r)
Eqn.
1
ER
i
=
Emission
rate
of
pollutant
i,
(
lb/
hr)
URE
i
=
Unit
risk
estimate
for
pollutant
i,(
µ
g/
m3)­
1
URE
r
=
Unit
risk
estimate
for
reference
HAP,(
µ
g/
m3)­
1
NCER
=
Normalized
carcinogenic
emission
rate,
(
lb/
hr)

NNER
=

(
ER
i
x(
RfC
r/
RfC
i)
Eqn.
2
ER
i
=
Emission
rate
of
pollutant
i,
(
lb/
hr)
RfC
i
=
Reference
concentration
for
pollutant
i,
(
µ
g/
m3)
RfC
r
=
Reference
concentration
for
reference
HAP,(
µ
g/
m3)
NNER
=
Normalized
non­
carcinogenic
emission
rate,
(
lb/
hr)

We
assumed
that
each
facility
operated
with
stacks
whose
average
stack
height
equaled
17
m,
an
approximate
midpoint
for
the
PCWP
source
category
based
on
available
engineering
data,
and
that
each
facility
had
a
minimum
distance
to
property
boundary
(
fenceline)
equal
to
200
m.
Thus,
our
conclusions
should
be
viewed
as
estimates
only.
The
actual
number
of
facilities
qualifying
as
3
low
risk
using
the
lookup
table
will
depend
on
the
values
of
the
site­
specific
average
stack
heights
and
fenceline
distances.

Results
and
Discussion
Table
1
shows
the
number
of
facilities
predicted
to
have
all
target­
organ
specific
HI
values
less
than
1.0
and
a
cancer
risk
less
that
1
in
1
million
based
on
the
lookup
table.
All
of
the
facilities
identified
as
low
risk
using
the
lookup
tables
were
among
the
facilities
identified
as
low
risk
using
the
more
site­
specific
chronic
analysis
and
the
acute
analysis
described
in
the
memo
from
February
18,
2004
titled
"
Risk
assessment
for
the
final
maximum
achievable
control
technology
(
MACT)
rule
for
the
plywood
and
composite
wood
products
(
PCWP)
source
category"
from
Scott
Jenkins,
Maria
Pimentel,
and
Dennis
Pagano
to
Dave
Guinnup.
Additionally,
none
of
the
facilities
that
failed
to
qualify
as
low
risk
in
the
site­
specific
chronic
analysis
or
the
acute
analysis
were
identified
as
low­
risk
using
the
lookup
tables.
This
result
suggests
that
our
lookup
tables
are
appropriately
health
protective
and
that
facilities
qualifying
as
low
risk
based
on
the
lookup
table
would
also
qualify
as
low
risk
based
on
a
more
sophisticated
site­
specific
chronic
and
acute
analysis.

Table
1
Predicted
Number
of
Low
Risk
Facilities
Using
Lookup
Table
Facilities
with
low
noncancer
risk
Facilities
with
low
cancer
risk
Facilities
with
both
low
cancer
and
noncancer
risk
41
109
36
Attachment
OAQPS:
ESD:
REAG:
SJenkins:
bmiles:
x5648:
C404­
01:
2/
25/
04
Appendix
A.

Non­
Cancer
Plywood
Lookup
Table:

fenceline(
m)

Stack
ht.(
m)
0
50
100
150
200
250
500
1000
1500
2000
3000
5000
5
2.51E­
01
2.51E­
01
3.16E­
01
3.16E­
01
3.16E­
01
3.16E­
01
3.16E­
01
3.46E­
01
4.66E­
01
6.21E­
01
9.82E­
01
1.80E+
00
10
5.62E­
01
5.62E­
01
5.62E­
01
5.62E­
01
5.62E­
01
5.62E­
01
5.62E­
01
5.70E­
01
6.33E­
01
7.71E­
01
1.13E+
00
1.97E+
00
20
1.43E+
00
1.43E+
00
1.43E+
00
1.43E+
00
1.43E+
00
1.43E+
00
1.43E+
00
1.43E+
00
1.68E+
00
1.83E+
00
2.26E+
00
3.51E+
00
30
2.36E+
00
2.36E+
00
2.36E+
00
2.36E+
00
2.36E+
00
2.36E+
00
2.53E+
00
3.04E+
00
3.04E+
00
3.33E+
00
4.45E+
00
5.81E+
00
40
3.11E+
00
3.11E+
00
3.11E+
00
3.11E+
00
3.11E+
00
3.11E+
00
3.42E+
00
4.04E+
00
5.07E+
00
5.51E+
00
6.39E+
00
9.63E+
00
50
3.93E+
00
3.93E+
00
3.93E+
00
3.93E+
00
3.93E+
00
3.93E+
00
4.49E+
00
4.92E+
00
6.95E+
00
7.35E+
00
8.99E+
00
1.25E+
01
60
4.83E+
00
4.83E+
00
4.83E+
00
4.83E+
00
4.83E+
00
4.83E+
00
5.56E+
00
6.13E+
00
7.80E+
00
1.01E+
01
1.10E+
01
1.63E+
01
70
5.77E+
00
5.77E+
00
5.77E+
00
5.77E+
00
5.77E+
00
5.77E+
00
6.45E+
00
7.71E+
00
8.83E+
00
1.18E+
01
1.36E+
01
1.86E+
01
80
6.74E+
00
6.74E+
00
6.74E+
00
6.74E+
00
6.74E+
00
6.74E+
00
7.12E+
00
9.50E+
00
1.01E+
01
1.29E+
01
1.72E+
01
2.13E+
01
100
8.87E+
00
8.87E+
00
8.87E+
00
8.87E+
00
8.87E+
00
8.87E+
00
8.88E+
00
1.19E+
01
1.37E+
01
1.55E+
01
2.38E+
01
2.89E+
01
200
1.70E+
01
1.70E+
01
1.70E+
01
1.70E+
01
1.70E+
01
1.70E+
01
1.70E+
01
2.05E+
01
2.93E+
01
3.06E+
01
4.02E+
01
4.93E+
01
Cancer
Plywood
Lookup
table
fenceline(
m)

Stack
ht.(
m)
0
50
100
150
200
250
500
1000
1500
2000
3000
5000
5
8.72E­
07
8.72E­
07
8.72E­
07
9.63E­
07
1.25E­
06
1.51E­
06
2.66E­
06
4.25E­
06
4.39E­
06
4.39E­
06
4.39E­
06
5.00E­
06
10
2.47E­
06
2.47E­
06
2.47E­
06
2.47E­
06
2.47E­
06
2.61E­
06
3.58E­
06
5.03E­
06
5.89E­
06
5.89E­
06
5.89E­
06
6.16E­
06
20
5.81E­
06
5.81E­
06
5.81E­
06
5.81E­
06
5.81E­
06
5.81E­
06
5.90E­
06
7.39E­
06
8.90E­
06
9.97E­
06
9.97E­
06
1.12E­
05
30
7.74E­
06
7.74E­
06
7.74E­
06
7.74E­
06
7.74E­
06
7.74E­
06
8.28E­
06
9.49E­
06
1.17E­
05
1.35E­
05
1.55E­
05
1.61E­
05
40
9.20E­
06
9.20E­
06
9.20E­
06
9.20E­
06
9.20E­
06
9.20E­
06
9.24E­
06
1.17E­
05
1.34E­
05
1.51E­
05
1.98E­
05
2.22E­
05
50
1.02E­
05
1.02E­
05
1.02E­
05
1.02E­
05
1.02E­
05
1.02E­
05
1.02E­
05
1.36E­
05
1.53E­
05
1.66E­
05
2.37E­
05
2.95E­
05
60
1.13E­
05
1.13E­
05
1.13E­
05
1.13E­
05
1.13E­
05
1.13E­
05
1.13E­
05
1.53E­
05
1.76E­
05
1.85E­
05
2.51E­
05
3.45E­
05
70
1.23E­
05
1.23E­
05
1.23E­
05
1.23E­
05
1.23E­
05
1.23E­
05
1.23E­
05
1.72E­
05
2.04E­
05
2.06E­
05
2.66E­
05
4.07E­
05
80
1.34E­
05
1.34E­
05
1.34E­
05
1.34E­
05
1.34E­
05
1.34E­
05
1.34E­
05
1.92E­
05
2.15E­
05
2.31E­
05
2.82E­
05
4.34E­
05
100
1.52E­
05
1.52E­
05
1.52E­
05
1.52E­
05
1.52E­
05
1.52E­
05
1.52E­
05
1.97E­
05
2.40E­
05
2.79E­
05
3.17E­
05
4.49E­
05
200
1.76E­
05
1.76E­
05
1.76E­
05
1.76E­
05
1.76E­
05
1.76E­
05
1.76E­
05
2.06E­
05
2.94E­
05
3.24E­
05
4.03E­
05
5.04E­
05