1
AF&
PA
Boiler
MACT
Priority
Questions
The
following
are
priority
questions
that
AF&
PA
and
its
member
companies
have
identified
that
need
to
be
addressed
before
Boiler
MACT
can
be
implemented
in
a
reasonable
manner.

A.
Risk:

1.
For
HCl
and
Mn
health
based
compliance
alternatives
(
Appendix
A),
must
all
boilers
comprising
the
affected
source
be
tested
or
only
the
solid
fuel
boilers?

Since
the
risk­
based
approach
only
applies
to
solid­
fuel
boilers,
only
solid
fuel
boilers
should
be
required
to
test.
The
Response
to
Comments
document
(
p.
185)
uses
the
term
"
affected
source"
when
discussing
the
health
based
alternative,
so
it
should
follow
that
the
only
units
to
be
tested
are
those
in
the
affected
source,
which
is
defined
as
a
subcategory
(
in
this
case
large
solid
fuel
fired
boilers).

2.
For
the
HCl
and
Mn
health
based
compliance
alternatives
(
Appendix
A),
can
fuel
tests
for
Cl
and
Mn
be
used
to
establish
emission
rates
in
lieu
of
stack
testing?

Fuel
testing
should
be
allowed
in
lieu
of
stack
testing
for
Mn
since
it
represents
the
highest
possible
emission
rate.
For
HCl,
chlorine
and
manganese,
the
permit
authority
should
also
accept
alternative
measures
of
the
emissions
including
the
use
of:
a)
default
values;
b)
fuel
analysis
data;
c)
historical
or
published
emissions
data;
or
d)
representative
testing
of
a
subset
of
the
affected
units
with
the
results
considered
representative
of
other
similar
units.

3.
The
rule
seems
to
require
that
health
based
compliance
alternative
parameters
must
be
incorporated
as
Federally
enforceable
limits
in
Title
V
permits
(
Item
10,
Appendix
A)
but
EPA
staff
has
verbally
advised
that
submittal
of
an
eligibility
demonstration
and
certification
to
the
permitting
authority
is
sufficient;
which
is
correct?

We
believe
submittal
of
the
demonstration
to
permitting
authority
and
EPA
should
be
sufficient
since
the
facility
cannot
control
how
long
a
state
may
actually
take
to
modify
the
Title
V
permit.
Modification
of
Title
V
may
involve
public
comment
which
could
stretch
out
review
beyond
a
year.

4.
Referring
affected
sources
to
the
EPA
web
site
for
retrieval
of
the
reference
concentrations
for
HCl,
CL2
and
Mn
is
cumbersome.
How
would
affected
sources
using
the
Health­
Based
Compliance
Alternative
know
that
changes
2
have
occurred?
Would
those
using
that
alternative
need
to
revise
their
compliance
demonstration
upon
future
changes
to
IRIS?

This
potential
confusion
could
be
eliminated
by
incorporating
the
reference
concentrations
from
the
referenced
web
site,
Table
1,
for
HCl,
Cl2
and
Mn
into
the
text
of
the
final
rule.
Should
IRIS
be
changed
in
the
future,
those
changes
could
be
incorporated
in
a
future
revision
of
the
rulemaking.

5.
Paragraph
4(
b)(
2)
requires
that
the
emission
tests
be
conducted
under
"
worstcase
operating
conditions.
For
many
sources,
the
composition
of
the
fuel
mixture
will
determine
the
worst­
case
conditions
(
e.
g.,
50
percent
bituminous
coal,
35%
wood,
and
15
percent
tire
derived
fuel).
What
is
the
averaging
time
for
calculating
the
fuel
mixture?

The
composition
of
the
"
worst­
case"
fuel
mixture
must
be
maintained
on
a
rolling
annual
basis.
A
twelve
month
rolling
average
is
consistent
with
the
Health
Based
Compliance
Option
which
addresses
chronic
effects
and
uses
annual
reference
concentrations.
This
is
also
consistent
with
the
suggested
approach
for
determining
continuous
compliance
with
fuel
operating
limits
(
see
E.
1
below).
The
rule
indicates
that
"
monthly
records
of
fuel
mix"
be
kept.
This
is
necessary
for
and
consistent
with
calculating
a
twelve
month
rolling
average.

B.
CO
limits:

1.
40
CFR
63.7525
(
a)(
6)
allows
excluding
data
from
averages
when
calculating
CO
emissions
when
the
boiler
is
operating
at
less
than
50%
of
rated
capacity;
however,
"
rated
capacity"
is
not
defined
in
the
rule.

All
new
boilers
will
have
rated
capacities
that
are
typically
reported
in
terms
of
boiler
heat
input,
e.
g.
million
Btu
per
hour,
or
in
the
amount
of
steam
produced,
e.
g.
thousands
of
pounds
of
steam
per
hour.
This
is
the
manufacturer's
"
boiler
plate"
maximum
continuous
rated
capacity
(
MCR),
i.
e.
manufacturer's
guaranteed
capacity.
This
capacity
value
should
be
used
when
applying
the
50%
threshold
provision.
Thus,
"
Boiler
Rated
Capacity"
should
be
defined
as
"
Boiler
rated
capacity
shall
be
equal
to
the
boiler
manufacturer's
maximum
continuous
rated
(
MCR)
capacity."

C.
Emissions
Averaging:

1.
In
many
instances,
multiple
boilers
have
a
common
outlet
duct
and
may
also
have
a
common
control
device.
The
Boiler
MACT
rule
indicates
that
40
CFR
63.8
(
b)(
2)
pertaining
to
multiple
sources
applies
(
Table
10).
This
can
lead
to
ludicrous
outcomes.
Can
we
collect
emissions
data
from
a
common
stack
or
does
data
need
to
be
collected
individually
for
each
boiler?
3
There
are
three
(
3)
situations
that
arise
regarding
this
question:

a)
If
multiple
boilers
are
ducted
to
a
common
control
device
(
see
sketch
below),
then
the
units
can
be
considered
as
a
single
unit
and
only
the
heat
inputs
need
to
be
added
b)
If
multiple
boilers
are
each
equipped
with
their
own
control
device
and
these
devices
have
different
operating
principles
(
see
sketch
below),
then
each
boiler
must
be
sampled
and
the
averaging
equations
stand
as
written
c)
If
multiple
boilers
are
each
equipped
with
their
own
control
device
and
these
devices
have
identical
operating
principles
(
see
sketch
below),
the
units
can
be
considered
as
a
single
unit
and
only
the
heat
inputs
need
to
be
added
Control
Device
Boiler
#
1
Boiler
#
2
Boiler
#
3
Sample
Control
Device
2
(
ESP)

Boiler
#
1
Boiler
#
2
Boiler
#
3
Sample
Control
Device
1
(
scrubber)
Control
Device
3
(
multiclone)
Sample
Sample
4
D.
Monitoring:

1.
A
two
point
calibration
is
required
every
8
hours
for
pH.
Is
this
there
an
alternative
that
EPA
would
find
acceptable?

Allow
the
use
of
a
daily
grab
sample
as
a
comparison
(
as
well
as
automated
check
for
"
flat­
line
response).
If
the
grab
agrees
within
specified
tolerance,
then
the
probe
is
in
calibration.
If
not,
the
probe
is
recalibrated.

E.
Fuel
Testing
and
Continuous
Compliance:

1.
The
rule
indicates
that
records
must
be
kept
of
the
fuel
type
and
quantity
burned
and
that
calculations
must
be
performed
to
demonstrate
continuous
compliance
with
the
fuel
operating
limit
(
whether
using
performance
tests
or
fuel
analysis);
however,
no
averaging
period
is
specified.
What
is
the
averaging
period
for
determining
continuous
compliance
with
the
fuel
operating
limits?

We
believe
that
a
twelve
month
rolling
average
determined
at
the
end
of
every
month
(
12
times
per
year)
is
the
appropriate
averaging
period
for
the
fuel
mix
operating
limit.
This
is
consistent
with
the
approach
used
for
emissions
averaging
in
section
63.7522.

F.
Performance
testing:

1.
The
rule
specifies
Method
5
for
particulate
testing.
Method
5
only
requires
the
"
front
half"
of
the
particulate
catch
be
included.
However,
some
states
require
inclusion
of
the
back
half
as
well.
Please
confirm
that
only
the
front
half
particulate
catch
is
required
under
Method
5
for
the
boiler
MACT
rule?

Only
the
front
half
catch
in
the
Method
5
test
is
required
to
be
reported
for
Boiler
MACT
as
this
is
the
common
approach
used
in
other
EPA
regulations
(
e.
g.,
Pulp
and
Paper
MACT
II)
and
what
the
method
specifies.
Furthermore,
the
particulate
emissions
data
that
EPA
used
to
develop
the
particulate
emission
standard
Control
Device
2
(
ESP)

Boiler
#
1
Boiler
#
2
Boiler
#
3
Control
Device
1
(
ESP)
Control
Device
3
(
ESP)
Sample
5
consisted
of
Method
5
front
half
only.
Finally,
the
Response
to
Comment
document
(
p.
128)
endorses
the
use
of
the
front
half
catch
for
any
PM
emission
limitation.
The
rule
itself
needs
to
state
this
as
well.

2.
Fuel
Analysis
Methods
Table
6
lists
acceptable
methods
for
conducting
fuel
testing
and
analyses.
This
list
appears
to
be
incomplete.
Also,
some
of
the
concentration
determination
methods
do
not
identify
methods
for
sample
preparation.
For
example,
EPA
Method
SW­
846­
9250
is
listed
for
chloride
concentration
determination,
but
this
method
is
for
the
colorimetric
determination
of
chloride
in
aqueous
solutions.
A
method
for
obtaining
an
aqueous
solution
from
a
solid
sample
is
also
needed.

AF&
PA
believes
there
are
other
widely
used
and
accepted
methods
besides
those
listed
in
the
table.
To
use
an
unlisted
method,
an
affected
source
will
have
to
prepare
a
justification
for
its
use.
This
justification
will
have
to
be
reviewed
and
approved
by
EPA
or
the
state
permitting
agency.
This
is
an
unproductive
use
of
resources
that
could
be
easily
avoided
through
addition
of
several
methods
to
Table
6.

AF&
PA
suggests
that
EPA
add
the
following
methods.

Heat
content
ASTM
D2015
Mercury
ASTM
D3684­
94,
ASTM
D6414­
99,
SW­
846­
7473
Mercury
(
following
appropriate
sample
preparation/
digestion)
EPA
1631E,
SW­
846­
7471B
Total
selected
metals
ASTM
D3683­
94;
ASTM
D6349­
99,
ASTM
D6357­
00a
Total
selected
metals
(
following
appropriate
sample
preparation/
digestion)
SW­
846­
6010,
SW­
846­
6020,
SW­
846­
7061
(
As),
SW­
846­
7741
(
Se),
metal­
specific
SW­
846
AA
and
GFAA
methods
Chloride
(
following
appropriate
sample
preparation/
digestion)
SW­
846­
9056
Chloride
SW­
846­
5050,
ASTM
D2361­
02
(
coal),
ASTM
D4208­
02
(
coal)

Furthermore,
the
words
"
or
equivalent"
should
be
added
in
Table
6
to
the
methods
for
determining
the
concentration
of
total
selected
metals
and
mercury.

G.
Overlap
with
PCWP
MACT
1.
Boilers
or
process
heaters
at
wood
product
mills
that
exhaust
flue
gases
to
a
direct
contact
dryer
system
most
of
the
time,
but
bypass
the
dryer
when
it
is
not
operating,
could
be
covered
by
both
the
Boiler
and
PCWP
6
MACTs.
According
to
the
PCWP
MACT,
when
the
boiler
is
venting
through
the
dryer
the
boiler
would
be
covered
by
the
PCWP
MACT.
However,
when
bypassing
the
dryer
the
boiler
could
be
subject
to
the
Boiler
MACT.
Dryers
are
bypassed
for
short
periods
of
time.
During
the
periods
when
the
dryer
is
being
bypassed,
can
the
boiler
be
considered
to
be
in
the
limited
use
subcategory?

These
boilers
should
be
considered
to
be
in
the
limited
use
boiler
subcategory
during
periods
when
the
dryer
is
bypassed
provided
that
the
annual
capacity
factor
for
bypass
periods
is
limited
by
permit
to
less
than
10%
of
the
rated
capacity
of
the
boiler.
The
annual
capacity
factor
can
be
calculated
as
the:
(
actual
Btu/
hr)
x
(
hours
of
direct
emissions
to
the
atmosphere)
/
(
rated
capacity
of
the
boiler)
/
(
8760
hr/
yr).

H.
Emissions
averaging
1.
§
63.7522(
b)
requires
sources
wishing
to
employ
the
emissions
averaging
option
to
show,
for
each
solid
fuel
boiler
to
be
included
in
averaging
calculations,
that
emission
levels
during
the
IPT
were
not
greater
than
those
"
achieved"
on
the
date
60
days
after
publication
of
the
rule
in
the
Federal
Register,
and
control
technology
employed
during
the
IPT
no
"
less
effective"
than
that
employed
60
days
after
publication
in
the
Federal
Register.
The
rule
does
not
explain
how
a
source
is
supposed
to
make
this
demonstration.
How
would
a
source
demonstrate
compliance
with
these
provisions?

It
is
clear
from
the
rule
preamble
that
EPA
does
not
intend
for
sources
to
demonstrate
compliance
with
§
63.7522(
b)
through
new
performance
testing.
Instead,
a
source
would
be
required
to
have
documentation
in
its
files
that
the
design,
operation,
and
maintenance
of
control
equipment
in
place
on
the
effective
date
of
the
boiler
MACT
rule
were
equivalent
to
or
less
effective
than
the
design,
operation
and
maintenance
of
the
control
equipment
used
to
demonstrate
compliance
with
the
emissions
averaging
provisions
during
the
IPT.
