RESPONSES
TO
SIGNIFICANT
PUBLIC
COMMENTS
CONCERNING
THE
PROPOSED
REVISION
OF
THE
DECEMBER
2000
APPROPRIATE
AND
NECESSARY
FINDING
AND
THE
PROPOSED
REMOVAL
OF
UTILITY
UNITS
FROM
THE
SECTION
112(
c)
LIST
Received
in
response
to:

Proposed
National
Emission
Standards
for
Hazardous
Air
Pollutants;
and,
in
the
Alternative,
Proposed
Standards
of
Performance
for
New
and
Existing
Stationary
Sources:
Electric
Utility
Steam
Generating
Units
(
69
FR
4652;
January
30,
2004)

Supplemental
Notice
for
the
Proposed
National
Emission
Standards
for
Hazardous
Air
Pollutants;
and,
in
the
Alternative,
Proposed
Standards
of
Performance
for
New
and
Existing
Stationary
Sources:
Electric
Utility
Steam
Generating
Units
(
69
FR
12398;
March
16,
2004)

Proposed
National
Emission
Standards
for
Hazardous
Air
Pollutants;
and,
in
the
Alternative,
Proposed
Standards
of
Performance
for
New
and
Existing
Stationary
Sources,
Electric
Utility
Steam
Generating
Units:
Notice
of
Data
Availability
(
69
FR
69864;
December
1,
2004)

Docket
Number
OAR­
2002­
0056
US
Environmental
Protection
Agency
Emissions
Standards
Division
Office
of
Air
Quality
Planning
and
Standards
Research
Triangle
Park,
North
Carolina
27711
15
March
2005
­
1­
1.0
INTRODUCTION
AND
BACKGROUND
In
January,
2004,
EPA
proposed
three
alternative
regulatory
approaches
for
addressing
hazardous
air
pollutants
(
HAP)
from
electric
utility
steam
generating
units
(
utilities
or
Utility
Units).
(
69
FR
4652;
January
30,
2004).
One
of
those
approaches
involved
revising
the
December
2000
finding
that
it
is
appropriate
and
necessary
to
regulate
coal­
and
oil­
fired
Utility
Units
under
section
112
of
the
Clean
Air
Act
(
CAA
or
the
Act),
removing
coal­
and
oil­
fired
Utility
Units
from
the
section
112(
c)
list,
and
issuing
standards
of
performance
for
new
and
existing
coal­
fired
Utility
Units
that
emit
mercury
(
Hg)
and
new
and
existing
oil­
fired
Utility
Units
that
emit
nickel
(
Ni).
Today,
we
are
finalizing
this
regulatory
approach,
except
we
are
not
taking
final
action
to
issue
proposed
standards
of
performance
for
nickel.

We
are
finalizing
this
regulatory
approach
in
two
separate
rulemaking
actions.
The
first
rule
revises
the
December
2000
regulatory
finding
and
removes
coal­
and
oil­
fired
utilities
from
the
section
112(
c)
list,
and
is
entitled,
"
Revision
of
December
2000
Regulatory
Finding
on
the
Emissions
of
Hazardous
Air
Pollutants
from
Electric
Utility
Steam
Generating
Units
and
the
Removal
of
Coal­
and
Oil­
fired
Electric
Utility
Steam
Generating
Units
from
the
Section
112(
c)
list."
The
second
rule
establishes
standards
of
performance
for
mercury
from
new
and
existing
coal­
fired
Utility
Units.
That
rule
is
called
"
Standards
of
Performance
for
New
and
Existing
Stationary
Sources:
Electric
Utility
Steam
Generating
Units,"
and
is
commonly
referred
to
as
the
Clean
Air
Mercury
Rule
(
CAMR).
Some
of
the
comments
addressed
in
this
document
relate
to
CAMR,
and
we
therefore
refer
the
reader
to
the
response
to
comments
document
in
support
of
that
rule.
Some
comments
refer
to
CAMR
because
EPA
proposed
the
revision
of
the
December
2000
finding
and
the
proposed
standards
of
performance
in
the
same
proposed
rule.

This
response
to
comments
document
responds
to
significant
comments
received
on
the
issues
addressed
in
the
final
rule
revising
the
December
2000
Finding.
In
January
2004,
EPA
specifically
proposed
that
it
should
not
have
concluded
that
it
was
appropriate
to
regulate
non­
Hg
HAP
from
coal­
fired
utilities
and
non­
Ni
HAP
from
oil­
fired
utilities.
EPA
explained
that
the
record
before
the
Agency
in
December
2000
did
not
support
the
conclusion
that
non­
Hg
and
non­
Ni
HAP
from
Utility
Units
cause
hazards
to
public
health
that
warrant
regulation.
EPA
further
proposed
that
it
erred
in
December
2000
in
finding
that
it
was
necessary
to
regulate
Hg
from
coalfired
units
and
Ni
from
oil­
fired
utility
units
under
section
112.
EPA
proposed
that
the
December
2000
necessary
finding
lacked
foundation
because
CAA
section
111
constituted
a
viable
statutory
mechanism
that,
if
implemented,
would
adequately
address
the
hazards
to
public
health
associated
with
emissions
of
Hg
and
Ni.
EPA
also
proposed
removing
coal­
and
oil­
fired
utility
units
from
the
section
112(
c)
list,
noting
that
it
had
erred
in
making
the
December
2000
finding
and
therefore
Utility
Units
should
never
have
been
included
on
the
section
112(
c)
list.
EPA
requested
comment
on
its
proposed
revision
of
the
December
2000
Finding
and
its
proposed
removal
of
coal­
and
oilfired
utility
units
from
the
section
112(
c)
list..

The
purpose
of
this
document
is
to
address
the
significant
public
comments
concerning
EPA's
proposed
revision
of
the
December
2000
finding
and
removal
of
coal­
and
oil­
fired
Utility
­
2­
Units
from
the
section
112(
c)
list,
that
we
received
in
response
to:
(
1)
the
notice
of
proposed
rulemaking
(
NPR),
"
Proposed
National
Emission
Standards
for
Hazardous
Air
Pollutants;
and,
in
the
Alternative,
Proposed
Standards
of
Performance
for
New
and
Existing
Stationary
Sources:
Electric
Utility
Steam
Generating
Units"
(
Clean
Air
Mercury
Rule;
CAMR)
(
69
FR
4652;
January
30,
2004);
(
2)
the
supplemental
notice
of
proposed
rulemaking
(
SNPR),
"
Supplemental
Notice
for
the
Proposed
National
Emission
Standards
for
Hazardous
Air
Pollutants;
and,
in
the
Alternative,
Proposed
Standards
of
Performance
for
New
and
Existing
Stationary
Sources:
Electric
Utility
Steam
Generating
Units"
(
69
FR
12398;
March
16,
2004);
and
(
3)
the
notice
of
data
availability
(
NODA),
"
Proposed
National
Emission
Standards
for
Hazardous
Air
Pollutants;
and,
in
the
Alternative,
Proposed
Standards
of
Performance
for
New
and
Existing
Stationary
Sources,
Electric
Utility
Steam
Generating
Units:
Notice
of
Data
Availability"
(
69
FR
69864;
December
1,
2004).
The
final
rule
contains
an
extensive
discussion
of
EPA's
interpretation
of
section
112(
n)(
1)(
A)
and
the
bases
for
revising
the
December
2000
action
and
removing
coal­
and
oilfired
Utility
Units
from
the
section
112(
c)
list.
The
final
rule
also
contains
responses
to
several
comments.

We
provided
an
opportunity
for
written
and
oral
public
comment
on
the
proposed
rulemaking,
and
that
opportunity
was
announced
with
the
NPR,
the
SNPR,
and
the
NODA.
Concurrent
public
hearings
on
the
NPR
were
held
on
February
25
and
26,
2004,
in
Chicago,
IL,
Philadelphia,
PA,
and
Research
Triangle
Park,
NC.
A
public
hearing
on
the
SNPR
was
held
on
March
31,
2004,
in
Denver,
CO.
No
public
hearing
was
held
on
the
NODA.
The
period
for
public
comment
on
the
NPR
closed
on
March
30,
2004,
but
was
extended
to
April
30,
2004,
upon
publication
of
the
SNPR.
Following
numerous
requests
for
an
extension,
the
public
comment
period
was
reopened
on
May
1,
2004,
and
extended
to
June
29,
2004.
The
public
comment
period
on
the
NODA
closed
on
January
3,
2005.

In
response
to
EPA's
three
proposed
alternative
regulatory
approaches,
EPA
received
approximately
500,000
comments
on
the
proposed
rulemaking,
including
numerous
mass­
mailings
and
approximately
5,000
"
unique"
comments.
A
listing
of
the
commenters
is
provided
in
Appendix
A
to
the
Response
to
Comments
in
support
of
CAMR.
A
complete
set
of
the
public
comments
received
and
the
public
hearing
transcripts
is
available
as
part
of
eDocket
OAR­
2002­
0056.
This
docket
can
be
accessed
at
www.
epa.
gov/
edocket
or
through
the
U.
S.
EPA
Docket
Center,
1301
Constitution
Avenue,
NW,
Washington,
D.
C.,
20004
in
the
Public
Reading
Room,
Room
B102,
EPA
West
Building,
8:
30
a.
m.
through
4:
30
p.
m.,
Monday
through
Friday.

A
summary
of
the
significant
public
comments
received
concerning
the
proposed
revision
of
the
December
2000
appropriate
and
necessary
finding
and
the
removal
of
coal­
and
oil­
fired
Utility
Units
from
the
section
112(
c)
list,
and
EPA's
responses
is
provided
below.
In
this
document,
EPA
has
followed
the
following
criteria:

!
Detailed
responses
are
provided
only
for
those
comments
deemed
to
be
significant.
Some
responses
to
significant
comments
are
provided
in
the
preamble
to
the
Final
Rule
Revising
the
December
2000
Finding.
Other
comments
may
be
summarized
and
general
responses
provided.
1
Some
commenters
on
section
112(
d)
discussed
alternative
measures
of
what
the
proper
emissions
standards
would
be
under
a
MACT,
or
criticized
EPA's
methodology
for
estimating
those
standards.
To
the
extent
these
commenters
have
stated,
or
believe,
that
EPA
should
have
performed
additional
MACT
calculations,
and
compared
these
revised
calculation
with
the
emissions
reductions
achieved
under
CAA
sections
110(
a)(
2)(
D)
and
111
before
reversing
its
December
2000
section
112(
n)(
1)(
A)
determination
or
promulgating
CAMR,
EPA
disagrees.
As
described
in
the
preamble,
EPA
does
not
believe
that
Congress
required
the
Agency
to
base
its
"
appropriate
and
necessary"
determination
on
a
comparison
with
MACT
or
other
section
112
requirements,
because
the
determination
would
necessarily
precede
any
actual
regulation
under
section
112,
and
hence
any
assumption
of
what
would
be
required
under
section
112(
d)
would
be
premature
and
speculative.

­
3­
!
Comments
determined
to
be
"
late
public
comments"
on
the
NODA
(
i.
e.,
received
after
the
close
of
the
public
comment
period
for
the
NODA)
are
neither
summarized
nor
are
responses
provided.
Comments
received
between
June
30,
2004
(
following
the
June
29,
2004,
end
of
the
public
comment
period
on
the
NPR
and
SNPR)
and
November
30,
2004
(
prior
to
the
December
1,
2004,
opening
of
the
public
comment
period
on
the
NODA)
were
considered
in
the
decisions
on
the
final
rule
because
the
comment
period
was
reopened
in
December
2004,
if
only
on
a
limited
number
of
issues.
Responses
are
not
provided
to
comments
received
after
the
close
of
the
public
comment
period
on
the
NODA
on
January
3,
2005,
because
there
was
insufficient
time
for
adequate
analyses
of
these
comments.

!
Comments
received
on
the
proposed
CAA
section
112(
d)
maximum
available
control
technology
(
MACT)
approach
and
on
the
proposed
approach
to
institute
a
cap­
and­
trade
rulemaking
under
the
authority
of
CAA
section
112(
n)(
1)(
A)
have
neither
been
summarized
nor
responded
to
in
this
document.
We
have
taken
this
approach
because
these
two
proposed
regulatory
approaches,
as
noted
above,
were
not
selected
for
promulgation.
1
­
4­
2.0
EPA'S
PROPOSED
REVISION
OF
THE
DECEMBER
2000
FINDING
A.
Proposed
Revision
of
Appropriate
and
Necessary
Finding:
General
Comments.

Comment:

Many
commenters
(
including
States
and
public
interest
groups)
stated
that
EPA
has
misconstrued
CAA
section
112(
n),
and
that
section
112
is
the
only
legal
authority
for
regulating
HAP.
The
commenters
also
assert
that
section
111
will
not
adequately
address
the
public
health
threats
posed
by
utility
units,
and
therefore
regulation
under
section
112
is
necessary.
(
OAR­
2002­
0056­
2108,
­
2330,
­
2332,
­
2823,
­
2575,
­
2823,
­
2880,
­
2871,
­
2878,
­
2889,
­
2920,
­
2924,
3393,
­
3394,­
3459).
According
to
these
commenters,

°
Commenter
OAR­
2002­
0056­
2575
stated
that
EPA's
position
concerning
the
proposed
revision
of
the
December
2000
finding
is
unreasonable
and
inconsistent
with
the
language
of
section
112(
n)(
1)(
A).
Section
112(
n)(
1)(
A)
clearly
states
that
EPA
must
impose
all
other
CAA
requirements
applicable
to
utility
units
before
carrying
out
the
Utility
RTC.
EPA's
position
that
it
can
now
regulate
Hg
emissions
under
section
111
(
6
years
after
completing
the
Utility
RTC)
directly
contradicts
the
"
after
imposition
of
this
chapter"
language
in
section
112(
n)(
1)(
A).
Section
112(
n)
requires
EPA
to
regulate
utility
units
"
under
this
section"
(
i.
e.,
section
112)
if
the
Administrator
finds
it
necessary
and
appropriate
to
do
so
based
on
the
impacts
on
public
health
(
as
evidenced
in
the
study)
and
not
on
the
availability
of
other
sections
of
the
CAA
to
regulate
utility
units.

°
Commenters
disputed
EPA's
conclusion
that
HAP
could
be
regulated
under
CAA
sections
111(
b)
and
(
d)
and
that
a
finding
of
"
necessary"
is
not
needed.
The
EPA's
interpretation
(
that
although
it
is
still
"
appropriate"
to
regulate
Hg
emissions,
it
is
not
"
necessary"
to
regulate
under
CAA
section
112
because
section
111
would
adequately
address
Hg
and
Ni
emissions)
is
unreasonable
and
inconsistent
with
the
plain
language
of
section
112(
n)(
1)(
A)
and
the
legislative
history.
The
process
outlined
in
section
112(
n)(
1)
did
not
supplant
sections
112(
c)
and
(
d)
as
the
statutory
mechanism
for
the
regulation
of
electric
utility
generating
units,
but
rather
required
EPA
to
make
a
threshold
determination
that
it
is
"
appropriate
and
necessary"
to
regulate
electric
utility
generating
units
before
proceeding
with
any
regulation
of
this
source
category.
Section
112(
n)(
1)
states
""
the
Administrator
shall
regulate
[
these
units]
under
this
section
[
112]
if
the
Administrator
finds
such
regulation
is
appropriate
and
necessary
after
considering
the
results
of
the
study..."".
If,
after
following
this
preliminary
process,
EPA
made
the
requisite
"
appropriate
and
necessary"
finding,
then
the
Administrator
is
required
to
regulate
electric
utility
generating
units
in
accordance
with
section
112,
which
requires
imposition
of
a
MACT
standard.
After
conducting
the
health
risk
study
under
section
112(
n),
EPA
determined
that
regulation
of
HAP
emissions
from
coal
and
oil­
fired
electric
utility
steam
generating
units
under
section
112
was
appropriate
and
necessary
and
added
these
units
to
the
list
of
source
­
5­
categories
under
section
112(
c)).
(
OAR­
2002­
0056­
2823)
and
public
interest
groups
(
OAR­
2002­
0056­
2173,
2575,
2823,
2878,
2920)

°
EPA
misconstrued
CAA
section
112(
n)(
1)(
A)
to
provide
that
HAP
emissions
from
power
plants
need
not
be
regulated
under
section
112
if
another
section
of
the
CAA
may
be
used
in
the
future
to
regulate
HAP
emissions.
Section
112(
n)(
1)(
A)
recognizes
that
power
plants
were
subject
to
requirements
for
non­
HAP
pollutants
(
e.
g.,
acid
rain,
ozone,
and
PM­
10)
which
other
sources
were
not.
Congress
required
that
EPA
study
whether
regulation
of
HAP
emissions
from
power
plants
was
necessary
in
light
of
the
emission
reductions
achieved
under
this
requirements
and
to
regulate
power
plants
if
it
was
appropriate
and
necessary
to
do
so
after
the
implementation
of
these
other
requirements.
Under
EPA's
interpretation
of
section
112(
n),
Congress
required
EPA
to
"
scour"
the
CAA
to
determine
if
there
was
any
other
regulatory
authority
besides
section
112.
If
Congress
had
intended
EPA
to
regulate
under
section
111
or
even
consider
it,
Congress
would
have
provided
so
in
the
legislation.
Commenter
OAR­
2002­
0056­
2823
adds
that
EPA's
reliance
on
Congressman
Oxley's
statement
is
misplaced
because
statements
of
individual
legislators
are
entitled
to
little
or
no
weight
in
construing
a
statute
(
See
National
Small
Shipments
Traffic
Conf.,
Inc.
v.
Civil
Aeronautics
Board,
618
F.
2d
819,
828,
D.
C.
Cir
1980).
Regarding
the
Oxley
statement,
commenter
OAR­
2002­
0056­
4139
adds
that
it
is
difficult
to
conceive
that
Congress
meant
EPA
to
consider
regulations
not
yet
conceived
or
proposed
such
as
111(
d)
when
reporting
to
Congress
on
the
study
of
HAP
from
utility
units.
(
OAR­
2002­
0056­
2823,
­
2173,
2575,
2823,
2878,
2920)

°
Commenter
OAR­
2002­
0056­
2359
also
disagreed
with
EPA's
assertion
that
section
111
adequately
address
environmental
effects
since
EPA
said
that
it
was
unable
to
quantify
the
contribution
of
emissions
to
the
health
effects
of
surrounding
populations.
If
it
can
no
determine
how
much
Hg
in
fish
is
contributed
by
coal­
fired
utility
units,
then
the
environmental
impacts
can
not
be
quantified.
Two
commenters
(
OAR­
2002­
0056­
2920,
­
3459)
stated
that
EPA's
claim
(
section
112
standards
are
not
necessary)
is
arbitrary
and
capricious
because:
(
1)
EPA
fails
to
explain
why
the
application
of
less
protective
requirements
under
section
111
would
make
section
112
standards
unnecessary;
EPA
does
not
quantify
the
benefits
of
Hg
control
or
describe
why
section
111
is
adequate,
and
(
2)
the
rulemaking
record
disproves
EPA's
belief
that
section
111
will
control
Hg
pollution
adequately,
when
compared
to
section
112
regulation.
The
proposed
section
111
scheme
results
in
far
weaker
controls
than
a
legitimate
MACT
standard.
Regulation
under
section
111
is
plainly
not
an
adequate
replacement
for
section
112
regulation,
considering
the
statutory
structure
of
the
CAA
and
the
number
of
ways
in
which
section
112
is
more
comprehensive
and
stringent.

°
Commenter
OAR­
2002­
0056­
2575
indicated
that
EPA
mischaracterized
its
December
2000
regulatory
finding.
EPA
argues
that
the
finding
was
over­
broad
and
the
record
supports
only
public
health
impacts
of
Hg.
The
clear
language
of
section
112
clearly
states
that
the
EPA
can
list
sources
of
HAP
based
on
human
health
or
environmental
effects;
­
6­
there
is
no
preference
for
one
category
of
effects
over
the
other.
A
finding
of
adverse
health
effects
does
not
mean
that
the
regulation
of
a
certain
HAP
is
not
necessary
under
section
112
as
EPA
now
claims.
The
public
health
and
environmental
impacts
of
Hg
are
well
established
and
have
been
acknowledged
by
EPA
in
several
documents.
It
is
disingenuous
for
EPA
to
now
assert
that
the
record
only
established
adverse
human
health
effects
as
a
justification
to
regulate
under
CAA
section
111.
Further,
EPA
never
identifies
the
basis
for
its
conclusion
that
the
record
for
its
regulatory
finding
was
deficient
with
regard
to
environmental
hazard.
The
regulatory
finding
clearly
states
it
conclusions
on
the
environmental
effects
of
methylmercury
(
MeHg)
on
fish
and
wildlife.
EPA
did
not
refute
the
validity
of
this
conclusion
or
identify
any
flaws
in
the
record.
Therefore,
EPA
has
no
rational
basis
for
overturning
the
December
2000
finding
and
in
turn,
no
basis
to
regulate
under
section
111
instead
of
112.

°
Many
states
opposed
EPA's
proposed
delisting.
According
to
Maryland,
EPA
asserted
a
plausible
link
between
methylmercury
concentrations
in
fish
and
mercury
emissions
from
power
plants
in
the
finding,
and
there
is
no
data
severing
that
link.
Pennsylvania
states
that
the
adverse
effects
of
exposure
to
mercury
emissions
are
not
rebutabble
and
EPA
failed
to
support
its
proposed
revision
with
any
scientific
evidence
that
mercury
emissions
from
power
plants
are
any
less
dangerous
than
they
were
in
December
2000.
Absent
new
and
compelling
evidence,
EPA
is
not
statutorily
authorized
to
revise
with
regulatory
determination.
New
Hampshire
adds
since
the
Utility
RTC,
other
researchers
have
found
plausible
links
between
the
mercury
concentration
in
the
blood
of
an
avian
indicator
species
(
loons)
and
in
their
eggs.
Michigan
cites
EPA's
preamble
statement
that
the
study
(
Utility
RTC)
"
reveals
that
there
are
no
confirmed
hazards
to
public
health
associated
with
emissions
of
such
HAPs.
We
do
not
believe
that
it
is
appropriate
to
regulate
coal
and
oil­
fired
utility
units
based
on
HAP
emissions
with
no
confirmed
health
effects"
and
that
the
conclusion
reached
in
December
2000
could
not
have
been
made
based
on
the
information
on
record
prior
to
2000.
EPA's
conclusions
appear
to
be
drawn
apart
from
the
conclusions
in
the
finding
and
the
scientific
evidence
referenced
in
the
finding.
There
is
no
question
on
whether
it
is
appropriate
or
necessary
to
regulate
these
sources;
EPA
must
regulate
mercury
emissions
under
section
112(
d).
New
York
states
that
EPA
has
no
authority
to
delist
utility
units
from
the
section
112
©
)
source
category
list
absent
compliance
with
the
criteria
in
section
112(
c)(
9)(
B)(
ii).
The
initial
listing
of
utility
units
was
not
a
mistake.
The
fact
that
EPA
reinterpreted
its
CAA
authority
without
performing
any
additional
technical
analyses
to
counter
the
previous
finding
of
"
appropriate
and
necessary"
makes
the
recision
unlawful.
Since
EPA
can
not
meet
this
criteria,
it
must
establish
appropriate
MACT
standards
under
section
112(
d).
3552
Missouri
contends
that
the
CAA
does
not
seem
to
allow
removing
a
source
category
from
one
section
and
not
from
another.
Section
112
©
)
(
1)
requires
that
to
the
extent
practicable,
the
categories
and
subcategories
listed
under
section
112
©
)
to
be
consistent
with
the
list
of
sources
listed
under
section
111.
This
implies
that
when
a
category
is
listed
under
section
111,
it
is
also
listed
under
112.
Section
112(
d)
requires
MACT
standards
for
sources
listed
under
section
112
©
)
.
One
State
commenter
(
OAR­
2002­
0056­
2436)
said
the
proposal
to
rescind
the
­
7­
December
2000
regulatory
determination
does
not
address
the
scientific
conclusions
reached
in
the
December
2000
determination.
EPA
must
address
the
scientifically
based
conclusions
relating
to
localized
health
and
environmental
impacts
of
a
Hg
cap
and
trade
program
prior
to
rescinding
the
determination.

°
Four
commenters
(
OAR­
2002­
0056­
2359,
­
2823,
­
2920,
­
3459)
contended
that
even
if
the
regulation
of
HAP
were
available
under
111(
d),
EPA's
proposal
under
section
111(
d)
is
not
an
adequate
substitute
for
section
112
regulation.
EPA
acted
arbitrarily
and
capriciously
in
implying
that
section
111
regulation,
including
a
cap
and
trade
approach,
is
adequate
to
address
the
harmful
regional
and
local
health
and
ecological
impacts
of
HAP
emissions
from
power
plants
(
2823).

°
Commenter
[
OAR­
2002­
0056­
5455]
disputes
the
claims
of
other
commenters
that
"
were
EPA
to
regulate
under
section
112(
d)
all
HAP
emissions
from
utility
boilers
based
on
a
determination
that
Hg
emissions
pose
a
hazard
to
public
health,
EPA
would
be
forced
to
impose
emissions
standards
that
would
supersede
other
provisions
in
the
CAA,
impermissibly
divesting
them
of
effect."
In
other
words,
the
other
commenters
argue,
regulation
under
CAA
section
112(
d)
"
would
subsume
other
provisions
of
the
CAA,
such
as
Title
IV."
In
short,
the
commenter
believes
that
EPA
and
the
States
possess
broad
authority
to
regulate
SO2
(
and
NOX
and
PM)
emissions
more
stringently
than
is
required
by
Title
IV.
Given
that
broad
authority,
commenter
OAR­
2002­
0056­
5455
argues
that
it
is
erroneous
to
claim
that
EPA
lacks
authority
to
regulate
HAP
from
power
plants
on
the
ground
that
this
action
would
effectively
require
additional
SO2
reductions.
The
commenter
reads
CAA
section
112
as
a
requirement
to
ensure
utility
HAP
reductions
through
adoption
of
section
112(
d)
MACT
standards
fits
comfortably
within
the
existing
statutory
structure
in
which
Titles
I
and
IV
act
together
to
require
reductions
in
all
of
the
regulated
air
pollutants
emitted
by
power
plants.
The
commenter
believes
that
section
112(
d)
requires
that
EPA
adopt
MACT
standards
for
all
power
plant
HAP
emissions,
and
that
numerous
other
CAA
provisions
require
power
plants
to
control
their
emissions,
notwithstanding
the
simultaneous
Title
IV
system
of
regulation.

Response:

EPA
disagrees
with
the
commenters
on
several
levels,
including
on
the
interpretation
of
section
112(
n)(
1)(
A)
and
the
application
of
that
interpretation
to
the
record
before
the
Agency.
Congress
enacted
CAA
section
112(
n)(
1)(
A)
specifically
to
address
Utility
Units.
Section
112(
n)(
1)(
A)
requires
EPA
to
study
the
hazards
to
public
health
"
reasonably
anticipated"
to
occur
as
a
result
of
utility
HAP
emissions
"
after
imposition
of
the
requirements
of
th[
e]
Act."
Section
112(
n)(
1)(
A)
further
provides
that
EPA
shall
regulate
Utility
Units
under
section
112
of
the
Act,
if
it
finds
that
it
is
both
"
appropriate"
and
"
necessary"
to
do
so
considering,
among
other
things,
the
results
of
the
Utility
Study.
Congress
required
that
the
study
be
completed
by
November
15,
1993,
but
set
no
deadline
for
the
appropriate
and
necessary
determination.
­
8­
As
explained
in
the
final
rule,
section
112(
n)(
1)(
A)
itself
contains
no
clear
standard
to
govern
EPA's
analysis
and
determination
of
whether
it
is
"
appropriate
and
necessary"
to
regulate
utilities
under
section
112.
The
first
sentence
of
the
subparagraph
describes
the
scope
of
the
study
EPA
is
to
conduct.
The
sentence
on
EPA's
"
appropriate
and
necessary"
finding
then
says
that
the
Agency
must
make
that
finding
after
considering
the
results
of
the
study.
But
Congress
did
not
supply
an
actual
definition
or
test
for
determining
whether
regulation
of
utilities
under
section
112
is
"
appropriate
and
necessary."
Thus,
EPA
must
supply
a
reasonable
interpretation
of
those
terms
to
fill
the
gap.

Congress'
direction
on
the
study
provides
the
only
guidance
in
section
112(
n)(
1)(
A)
about
the
substance
of
EPA's
appropriate
and
necessary
inquiry.
Because
the
statute
provides
no
other
explicit
guidance,
EPA
has
chosen
to
extrapolate
from
Congress'
description
of
the
study
to
adopt
a
reasonable
interpretation
of
the
phrase
"
appropriate
and
necessary."
The
final
rule
provides
an
extensive
discussion
of
EPA's
interpretation
of
section
112(
n)(
1)(
A).
As
is
relevant
here,
however,
EPA
disagrees
with
commenters'
assertion
that
EPA
cannot
regulate
Hg
emissions
from
coal­
fired
utility
units
under
section
111
because
such
action
contradicts
the
phrase
"
after
imposition
of
the
requirements
of
the
Act"
in
section
112(
n)(
1)(
A).

As
explained
in
the
final
rule,
EPA
reasonably
interprets
the
phrase
"
imposition
of
the
requirements
of
th[
e]
Act"
to
include
not
only
those
requirements
already
imposed
and
in
effect,
but
also
those
requirements
that
EPA
reasonably
anticipates
will
be
implemented
and
will
result
in
reductions
of
utility
HAP
emissions.
In
the
study,
Congress
asked
EPA
to
identify
the
utility
HAP
emissions
that
would
remain
"
after
imposition
of
the
requirements
of
th[
e]
Act"
and
identify
the
hazards
to
public
health
reasonably
anticipated
to
occur
as
the
result
of
such
emissions.
Further,
as
explained
in
the
final
rule,
EPA
interprets
section
112(
n)(
1)
to
provide
that
the
appropriate
and
necessary
finding
is
to
be
made
by
reference
to
the
utility
HAP
emissions
that
remain
"
after
imposition
of
the
requirements
of
th[
e]
Act."

EPA
disagrees
that
the
phrase
"
after
imposition
of
the
requirements
of
th[
e]
Act,"
means
that
EPA
must
propose
or
promulgate
all
requirements
applicable
to
Utility
Units
prior
to
the
Utility
Study.
Congress
required
that
the
Utility
Study
be
completed
in
November
1993,
which
is
two
years
prior
to
commencement
of
the
first
phase
of
Title
IV,
which
is
a
significant
regulatory
program
that
impacts
utility
emissions.
Given
the
timing
for
completion
of
the
study
and
the
fact
that
Congress
added
Title
IV
in
1990,
Congress
could
not
have
reasonably
intended
for
EPA
to
limit
its
consideration
of
requirements
that
either
had
been
proposed
or
promulgated
by
that
date.
EPA's
interpretation
of
the
phrase
"
after
imposition
of
the
requirements
of
th[
e]
Act"
is
reasonably.
See
generally
136
Cong.
Rec.
H12911,
12934
(
daily
ed.
Oct.
26,
1990)
(
statement
of
Congressman
Oxley)
(
recognizing
that
the
control
of
other
pollutants
under
other
requirements
of
the
Act,
including
the
Acid
Rain
Program
in
Title
IV,
would
result
in
utility
HAP
reductions).
In
addition,
because
Congress
did
not
set
a
deadline
for
making
the
appropriate
and
necessary
determination,
EPA
can
reasonably
consider
new
information
obtained
after
the
study,
particularly
where
that
new
information
affects
the
level
of
emissions
that
would
remain
following
"
imposition
of
the
requirements
of
th[
e]
Act,"
which,
as
noted
above,
is
our
guide
for
assessing
­
9­
whether
it
is
appropriate
and
necessary
to
regulate
utilities
under
section
112.

EPA
concludes
in
the
final
rule
that
it
erred
in
December
2000
in
finding
that
it
was
appropriate
to
regulate
coal­
fired
Utility
Units
on
the
basis
of
Hg
emissions.
EPA
specifically
failed
to
fully
account
for
the
Hg
emissions
remaining
after
"
imposition
of
the
requirements
of
th[
e]
Act."
That
failure
resulted
in
an
overestimate
of
the
remaining
utility
Hg
emissions.
Had
we
properly
considered
the
Hg
reductions
remaining
"
after
imposition
of
the
requirements
of
th[
e]
Act"
in
December
2000,
we
might
well
have
(
and,
as
discussed
in
the
final
rule,
now
believe
should
have)
reached
a
different
conclusion
as
to
whether
it
was
"
appropriate"
to
regulate
coalfired
units
on
the
basis
of
Hg
emissions.
EPA
further
concludes
in
the
final
rule
that
recent
information
confirms
that
it
is
not
appropriate
to
regulate
coal­
fired
Utility
Units
under
section
112
on
the
basis
of
Hg
emissions,
because
the
emissions
remaining
after
implementation
of
CAA
section
110(
a)(
2)(
D),
and
independently
section
111,
will
result
in
levels
of
Hg
emissions
that
are
not
reasonably
anticipated
to
cause
hazards
to
public
health.
EPA
recently
signed
rules
implementing
these
two
statutory
provisions
and
those
regulations
will
obtain
important
utility
Hg
reductions.

In
any
event,
even
if
Congress
contemplated
a
more
limited
set
of
requirements
when
it
referred
to
the
"
imposition
of
the
requirements
of
th[
e]
Act,"
EPA
concludes
that
it
is
still
not
necessary
to
regulate
Hg
emissions
from
coal­
fired
utility
units
under
section
112
because
section
111
constitutes
a
viable
statutory
authority
that
will
effectively
address
the
Hg
emissions
remaining
"
after
imposition
of
the
requirements
of
th[
e]
Act.
We
interpret
the
"
necessary"
prong
of
the
section
112(
n)(
1)(
A)
inquiry
to
require
EPA
to
examine
whether
there
are
any
other
available
authorities
under
the
CAA
that,
if
implemented,
would
effectively
address
the
remaining
Hg
emissions
from
coal­
fired
Utility
Units.
See
Final
Rule
Revising
December
2000
Finding
(
explaining
why
regulation
under
section
110(
a)(
2)(
D)
and
111
would
effectively
address
the
Hg
utility
emissions
remaining
after
imposition
of
the
requirements
of
the
Act.).
We
disagree
with
those
commenters
that
suggest
that
the
appropriate
and
necessary
inquiries
are
solely
healthbased
inquiries.
Congress
provided
EPA
discretion
in
section
112(
n)(
1)(
A)
to
determine
whether
regulation
of
Utility
Units
under
section
112
was
both
"
appropriate"
and
"
necessary."
Our
interpretation
gives
effect
to
both
terms,
which
commenters'
arguments
do
not.
Further,
EPA's
interpretation
of
these
terms,
as
set
forth
in
detail
in
the
final
rule,
is
a
permissible
construction.
Further,
there
is
no
legislative
history
indicating
to
the
contrary.

Finally,
contrary
to
commenters'
assertions,
we
conclude,
based
on
additional
modeling
and
analyses
of
the
data,
that
Hg
emissions
remaining
after
implementation
of
CAIR,
and
independently
CAMR,
are
not
reasonably
anticipated
to
cause
hazards
to
public
health.
EPA's
analysis
in
this
regard
is
set
forth
in
detail
in
the
final
rule.
As
for
environmental
effects,
EPA
interprets
section
112(
n)(
1)(
A)
as
not
requiring
EPA
to
study
or
base
its
appropriate
and
necessary
determination
on
environmental
effects
that
are
unrelated
to
public
health.
Nevertheless,
as
EPA
explains
in
the
final
rule,
EPA
believes
that
it
can
consider
environmental
effects
that
are
unrelated
to
public
health,
such
as
the
effects
of
methymercury
on
loons
and
racoons
and
other
wildlife,
in
determining
whether
it
is
appropriate
to
regulate
utilities
under
­
10­
section
112,
but
those
non
public­
health
considerations
cannot
alone
or
in
combination
with
one
another
justify
regulation
of
Utility
Units
under
section
112
where,
as
here,
EPA
has
concluded
that
hazards
to
public
health
are
not
reasonably
anticipated
to
result
from
utility
HAP
emissions
remaining
after
imposition
of
the
requirements
of
the
Act.
Because
EPA
has
concluded
that
utility
Hg
emissions
remaining
after
imposition
of
the
requirements
of
the
Act
are
not
reasonably
anticipated
to
cause
hazards
to
public
health,
it
reasonably
did
not
consider
environmental
effects
unrelated
to
public
health.
EPA's
interpretation
of
section
112(
n)(
1)(
A)
concerning
environmental
effects
is
reasonable
given
the
language
of
section
112(
n)(
1)(
A),
unlike
other
provision
in
section
112,
does
not
refer
to
environmental
effects
To
the
extent
the
above
comment
summaries
dispute
EPA's
authority
to
regulate
HAP
under
section
111(
d)
or
address
EPA's
appropriate
and
necessary
finding
with
regard
to
non­
Hg
HAP,
please
refer
to
the
sections
below.

B.
Is
it
Appropriate
and
Necessary
to
Regulate
Coal­
fired
Units
under
section
112
on
the
Basis
Hg
Emissions?

Comment:

Many
industry
commenters
argued
that
EPA
has
not
demonstrated
that
regulation
of
Hg
emissions
from
coal­
fired
power
plants
is
appropriate
and
necessary
under
section
112
The
agency's
Utility
Report
to
Congress
found
only
that
Hg
was
the
hazardous
pollutant
of
"
greatest
concern."
It
did
not
include
a
finding
that
Hg
emissions
from
coal­
fired
power
plants
posed
a
public
health
concern.
EPA's
December
2000
decision
to
regulate
Hg
emissions
from
coal­
fired
power
plants
does
not
contain
a
concise
explanation
of
the
factual
bases
for
the
agency's
conclusions
that
Hg
emissions
from
these
sources
a
risk
to
public
health
that
warrants
regulation.
The
commenters
do
not
accept
at
face
value
that
EPA
has
made
a
""
plausible
link""
between
mercury
HAP
emission
from
utility
boilers
and
the
potential
health
impacts
and
human
exposure
Commenter
OAR­
2002­
0056­
2922
also
states
that
the
reference
does
for
MeHg
is
highly
conservative
and
that
EPRI
analyses
show
that
significant
reductions
in
Hg
emissions
from
coalfired
plants
will
result
in
little
change
in
human
exposures
in
the
U.
S.
that
[
OAR­
2002­
0056­
2365,
2422,
2560,
2661,
2861,
2867,
­
2891,
­
2922,
­
2948,
3200,
3403,
­
3432,
­
3445,
­
3530,
­
3537)

According
to
Commenter
2867
and
others,
the
1998
Report
to
Congress,
the
December
2000
determination,
and
the
preamble
to
the
proposed
rule
all
reflect
the
multitude
of
unanswered
questions
that
make
it
impossible
for
EPA
to
conclude
that
any
hazard
to
public
health
can
reasonably
be
anticipated
to
result
from
emissions
from
utility
units
after
the
imposition
of
the
other
requirements
of
the
Clean
Air
Act.
Specifically:

°
The
basis
for
the
proposed
regulatory
action
is
the
EPA
mercury
and
utility
studies
conducted
under
Section
112
(
n)(
l)(
A)
and
(
B).
The
commenter
states
that
neither
of
these
studies
concluded
that
mercury
or
nickel
emissions
from
power
plants
posed
a
specific
risk
to
human
health.
­
11­
°
All
of
the
work
performed
to
date
by
EPRI
indicates
that
U.
S.
utility
mercury
emissions
represent
approximately
one
percent
of
total
global
mercury
in
the
atmosphere,
that
deposition
patterns
of
mercury
are
not
a
true
indicator
of
exposure,
that
only
methylated
forms
of
mercury
are
bioavailable
and
accumulate
in
fish
tissues,
and
that
total
elimination
of
U.
S.
utility
mercury
emissions
would
have
no
discernible
impact
on
the
exposure
of
sensitive
populations
to
high
levels
of
mercury
through
consumption
of
fish.

°
The
commenter
claims
that
generic
inferences
to
a
""
plausible
link""
between
mercury
emissions
from
power
plants
and
methyl
mercury
concentrations
in
fish
consumed
by
local
populations
(
the
human
exposure
pathway)
as
the
basis
for
emissions
reductions
are
scientifically
and
technically
unsound
(
69
Fed.
Reg.
at
4658).
The
commenter
believes
that
EPA
has
failed
to
adequately:
a)
Establish
source­
receptor
linkages,
b)
Account
for
the
high
percentages
of
deep
sea
and
farm­
raised
fish
consumed
as
part
of
the
American
diet,
or
c)
Provide
any
evidence
of
quantifiable
health
benefits
in
support
of
its
call
for
mercury
emission
reductions
from
power
plants.

°
The
commenter
points
out
furthermore,
EPA
has
recognized
in
the
preamble
that
speculative
theories
about
power
plant
emissions
being
responsible
for
creating
localized
mercury
hot
spots
are
unsupportable.
Importantly,
there
does
not
seem
to
be
a
scientific
definition
of
a
hotspot.
The
commenter
claims
that
EPRl's
comments
in
this
docket
dispel
the
myth
of
hot
spots,
using
different
interpretations
of
the
term.

°
The
commenter
notes
that
of
particular
significance
in
the
context
of
the
proposed
mercury
rulemaking
are
the
following
conclusions
from
additional
modeling
efforts
performed
by
EPRI:
1)
Even
with
a
70%
reduction
in
US
power
plant
mercury
emissions
(
of
an
estimated
48
Tons
per
year)
to
15
Tons,
US
mercury
deposition
would
change
on
an
average
6.9%.
This
disparity
results
from
the
fact
that
70%
of
the
mercury
deposited
in
the
United
States
is
believed
to
originate
outside
of
the
US,
2)
From
an
economic
perspective,
the
estimated
costs
of
such
mercury
reductions
would
run
into
several
billion
dollars,
3)
And
from
an
environmental
perspective,
despite
these
levels
of
reduction
in
power
plant
mercury
emissions
the
benefits
may
not
be
discernable,
when
translated
to
reductions
in
fish
advisories
(
the
principal
measurement
yardstick
for
the
effectiveness
of
the
proposed
mercury
regulations),
4)
The
""
reference
dose
value""
(
RID)
on
which
fish
advisories
are
premised
have
an
inherent
margin
of
built­
in
safety,
and
continuing
research
in
the
Seychelles
study
has
demonstrated
no
observable
health
effects
in
sensitive
populations
at
exposure
levels
far
in
excess
of
EPA's
RID.

°
The
commenter
claims
EPA
has
offered
no
plausible
scientific
evidence
of
a
link
between
mercury
air
emissions
and
cardiovascular
related
health
effects.

°
The
commenter
concludes
that
EPA
has
confirmed
its
decision
not
to
regulate
HAPs
other
than
mercury
and
nickel,
on
the
grounds
that
these
other
HAPS
do
not
pose
a
risk
to
public
health.
EPRI's
Research
findings
have
arrived
at
these
same
conclusions.
The
commenter
­
12­
states
that
EPA
has
also
recognized
that
the
CAA
limits
EPA's
authority
to
regulate
utility
HAPs
based
only
on
health
effects,
not
effects
on
other
environmental
media.
The
commenter
recommends
that
this
conclusion
should
be
adopted,
as
part
of
the
final
rule
and
the
December
2000
finding
should
also
be
revised
appropriately.

According
to
Commenter
2861,
while
utilities
may
be
the
largest
U.
S.
source
of
mercury
emissions,
they
account
for
only
about
one
percent
of
total
global
mercury
emissions.
The
commenter
states
that
EPA
thus
far
has
failed
to
provide
an
estimate
of:
1)
the
amount
of
methylmercury
in
fish
currently
consumed
in
the
U.
S.
that
comes
from
U.
S.
power
plants
emissions;
2)
the
reduction
in
the
concentration
of
methylmercury
in
fish
consumed
in
the
U.
S.
that
might
be
expected
from
the
reduction
in
power
plant
mercury
emissions
that
EPA
is
proposing;
and
3)
the
resulting
reduction
in
human
exposure,
or
the
time
over
which
any
change
in
methylmercury
concentrations
and
reduced
exposure
might
occur.
The
commenter
believes
all
are
necessary
to
support
the
regulation
of
mercury
emissions.
The
commenter
states
there
is
also
a
problem
with
the
method
EPA
used
to
derive
its
highly
conservative
reference
dose
for
mercury,
which
is
lower
than
comparable
values
derived
by
other
federal
or
international
agencies.
EPA
relied
solely
on
the
results
of
the
Faroe
Islands
study,
totally
ignoring
an
equally
detailed
and
more
credible
study
performed
in
the
Seychelle
Islands
which
did
not
find
the
same
adverse
developmental
effects
from
methylmercury
exposure
found
in
the
Faroe
Islands
study,
and
which
doesn't
suffer
from
the
confounding
effects
of
PCBs
that
the
Faroe
Islands
study
does.
The
commenter
notes
that
other
organizations
use
the
results
of
the
Seychelles
Island
study
as
part
of
their
analyses
and
arrive
at
much
higher
reference
doses.
The
commenter
claims
that
EPA
compounds
its
failure
to
consider
all
credible
scientific
information
by
applying
a
scientifically
unjustified
and
excessively
high
uncertainty
factor
of
10
in
setting
its
reference
dose.
The
World
Health
Organization
and
the
Agency
for
Toxic
Substances
and
Disease
Registry
use
uncertainty
factors
of
6.4
and
4.5
respectively.

The
commenter
states
that
analyses
by
the
Electric
Power
Research
Institute
demonstrate
that
by
reducing
power
plant
mercury
emissions
to
EPA's
proposed
15
ton
emissions
cap
level,
exposure
to
methylmercury
by
women
of
childbearing
age
would
be
reduced
by
less
than
one
percent.
Given
the
lack
of
a
factual
case
demonstrating
a
link
between
power
plant
mercury
emissions
and
methylmercury
levels
in
fish,
the
lack
of
available
controls
designed
specifically
to
remove
mercury,
and
the
uncertainty
of
whether
emissions
reductions
would
actually
achieve
any
significant
reduction
in
exposure,
the
commenter
certainly
agrees
with
EPA's
conclusion
that
regulation
under
the
Section
112
MACT
standards
is
not
warranted.
The
commenter
adds
that
for
these
same
reasons,
there
is
no
justification
for
regulation
under
Section
112(
n)(
1)(
A).
The
commenter
asserts
that
in
fact,
since
EPA
has
not
quantified
the
risk
and
failed
to
acknowledge
the
many
issues
related
to
the
control
of
mercury
that
remain
unresolved,
the
only
findings
to
date
warrant
that
EPA
rescind
the
December
20,
2000
finding
entirely."

Commenter
3537
asserted
that
EPA's
conclusion
that
regulation
of
Hg
emissions
from
utility
units
is
appropriate
and
necessary
was
not
supported
by
the
record.
The
commenter
stated
first,
EPA's
RfD
for
MeHg
was
overly
conservative
and
should
be
used
only
as
a
screening
tool
for
deciding
when
health
concerns
are
non­
existent,
not
as
the
basis
for
concluding
that
exposures
above
­
13­
the
RfD
result
in
adverse
health
effects.
Second,
EPA's
reliance
on
a
"
plausible
link"
between
anthropogenic
releases
of
Hg
from
industrial
and
combustion
sources
in
the
U.
S.
and
MeHg
in
fish
was
insufficient
to
justify
regulation.
The
commenter
stated
that
EPA's
failure
to
quantify
its
plausible
linkage
theory
prevented
it
from
concluding
that
regulation
of
utility
units
pursuant
to
section
112(
n)(
1)(
A)
was
appropriate
and
necessary
to
protect
public
health.
Third,
the
fact
that
Utility
Units
are
the
largest
source
of
Hg
emissions
in
the
U.
S.
did
not
warrant
a
finding
that
the
regulation
is
appropriate
and
necessary
under
section
112(
n)(
1)(
A).
Instead,
the
commenter
believed
EPA
must
establish
a
relationship
between
Hg
emissions
from
utility
units
and
the
effects
of
such
emissions
on
public
health,
before
the
appropriate
and
necessary
finding
under
section
112(
n)(
1)(
A)
could
be
made.
The
commenter
stated
that
EPA
failed
to
do
this.
Fourth,
the
use
of
fish
advisories
as
a
justification
for
listing
ignored
the
fact
that
EPA
could
not
quantify
how
much
MeHg
in
fish
consumed
in
the
U.
S.
population
is
contributed
by
utility
unit
emissions.
The
commenter
submitted,
in
other
words,
that
fish
advisories
could
not
be
used
to
conclude
that
Utility
Units
pose
risks
to
public
health.
Fifth,
EPA's
speculation
about
the
plausible
health
benefits
from
the
control
of
Hg
emissions
from
utility
units
was
not
supported
by
the
EPRI's
actual
analyses.
EPRI
concluded,
among
other
things,
that
even
if
Hg
emissions
from
coal­
fired
power
plants
were
reduced
from
45
to
15
tons
per
year,
Hg
deposition
in
the
U.
S.
would
only
be
reduced
from
165.4
tons
per
year
to
153.9
tons
per
year
(
or
6.9
percent
of
the
total
annual
Hg
deposition
in
the
U.
S.)
The
commenter
stated
that
such
a
small
reduction
in
Hg
deposition
in
the
U.
S.
would
have
little
effect
on
the
exposures
to
women
of
child­
bearing
age.
The
commenter
noted
the
Hg
exposure
to
this
population
subgroup
would
only
be
reduced
by
0.5
percent
to
0.75
percent.
The
exposures
of
the
fraction
of
the
population
predicted
to
be
above
EPA's
RfD
would
only
be
reduced
by
0.064
percent.
According
to
the
commenter,
these
small
predicted
percentage
reductions
in
the
population
above
the
RfD
brought
into
question
whether
any
observable
public
health
benefit
would
be
realized
as
a
result
of
significant
reductions
in
Hg
emissions
from
Utility
Units.
The
commenter
stated
that
the
rulemaking
record
did
not
contain
sufficient
factual
evidence
to
conclude
that
Hg
emissions
from
coal­
fired
power
plants
present
a
public
health
concern.
Therefore,
the
commenter
submitted
that
EPA
must
reconsider
its
decision
and
must
delist
Utility
Units
from
CAA
section
112
©
)
.

Response:

EPA
agrees
with
the
commenters
that
it
is
neither
appropriate
nor
necessary
to
regulate
coal­
fired
utility
units
under
section
112
on
the
basis
of
Hg
emissions,
but
for
different
reasons
than
those
articulated
by
the
commenters.
The
Agency
articulates
those
reasons
in
the
preamble
and
the
technical
support
documents.

C.
Is
it
Appropriate
and
Necessary
to
Regulate
Coal­
fired
Units
under
section
112
on
the
Basis
non­
Hg
Emissions
and
Oil­
fired
units
under
section
112
on
the
basis
of
Non­
Ni
HAP.
­
14­
Comment:

The
commenters
contend
that
CAA
section
112(
c)(
2)
requires
EPA
to
promulgate
emission
standards
for
all
power
plant
HAP
emitted
in
significant
quantities
from
coal
and
oil­
fired
units
(
a
listed
source
category).

°
Commenter
OAR­
2002­
0056­
2817
indicated
that
EPA's
rationale
for
not
regulating
non­
Hg
HAP
relies
heavily
on
Latham
and
Watkins
memorandum.
EPA
declined
to
collect
any
more
data
or
perform
any
additional
analyses.
The
only
additional
information
provided
is
an
inadequate
modeling
of
HCl
emissions
for
two
hypothetical
plants.

°
Three
commenters
(
OAR­
2002­
0056­
2823,
­
2878,
­
3459)
stated
that
CAA
section
112(
c)(
2)
requires
EPA
to
promulgate
emission
standards
for
all
power
plant
HAP
emitted
in
significant
quantities
from
coal
and
oil­
fired
units
(
a
listed
source
category);
the
CAA
does
not
authorize
EPA
to
pick
and
choose
the
HAP
it
will
regulate
(
National
Lime
Association
v
EPA
,233
F.
3d
625,634
(
D.
C.
Cir.
2000).

°
Commenter
OAR­
2002­
0054­
2823
stated
that
although
EPA
identified
Hg
as
the
HAP
of
greatest
concern,
there
are
many
other
HAP
emitted
in
significant
amounts
from
this
source
category
that
result
in
adverse
human
health
or
environmental
effects.
The
only
way
for
EPA
to
legally
avoid
the
obligation
is
to
delist
the
source
category,
which
EPA
failed
to
do.
In
other
rulemakings,
such
as
the
industrial
boiler
(
IB)
rule,
EPA
regulated
the
same
HAP
that
EPA
refused
to
regulate
under
this
proposal.
EPA
must
revise
its
proposed
determination
that
regulation
of
these
HAP
is
both
inappropriate
and
unnecessary,
and
should
adopt
appropriate
emissions
standards
for
all
HAP
emitted
in
coal
and
oil­
fired
units
in
significant
amounts.

°
Commenter
OAR­
2002­
0054­
3449
indicated
that
EPA
is
required
to
regulate
all
HAP
listed
in
section
112(
b)
as
a
result
of
its
December
2000
finding
that
it
is
necessary
and
appropriate
to
regulate
electric
utility
steam
generating
units
under
section
112.
Emissions
of
other
HAP
do
warrant
regulation;
the
Utility
RTC
concluded
that
other
HAP
of
potential
concern
include
arsenic
(
As),
chromium
(
Cr),
cadmium
(
Cd),
dioxins,
hydrogen
chloride
(
HCl),
and
hydrogen
fluoride
(
HF).
These
other
HAP
can
be
controlled
by
currently
available
technology
such
as
scrubbers
(
for
acid
gases)
and
baghouses
(
for
metals
and
dioxin),
which
also
are
effective
Hg
controls.
In
the
IB
rule,
EPA
acknowledged
the
health
effects
of
the
same
HAP,
and
promulgated
limits
for
Hg,
non­
Hg
metallic
HAP,
inorganic
HAP,
and
organic
HAP
using
surrogates.
This
contradicts
EPA's
statement
that
information
obtained
since
the
Utility
RTC
reveal
no
health
risk
warranting
regulation.
It
also
contradicts
the
Federal
Plan
requirements
for
municipal
waste
incinerators
which
control
Hg
and
non­
Hg
HAP
for
existing
units.
EPA
should
regulate
all
significant
HAP
from
utility
units.
­
15­
°
Commenter
OAR­
2002­
0054­
3459
stated
that
the
record
supports
the
development
of
limits
for
non­
Hg
HAP
emitted
by
utility
units.
The
health
and
environmental
effects
are
well­
documented.
EPA
can
not
hide
behind
a
supposed
lack
of
data
and
use
that
to
avoid
setting
standards
because
EPA
has
authority
to
collect
necessary
information
and
the
environmental
community
has
repeated
urged
EPA
to
augment
its
data
if
EPA
felt
more
were
needed.
However,
available
stack
test
data
is
by
itself
sufficient
to
support
limits
for
non­
Hg
HAP
metals
from
coal­
fired
units
and
EPA
must
use
these
data
to
set
standards.
The
currently
available
data
for
other
non­
Hg
HAP
do
not
appear
sufficient.

°
Two
commenters
(
OAR­
2002­
0056­
2920,
­
2767)
indicated
that
EPA's
failure
to
set
standards
for
each
of
the
HAP
emitted
by
powerplants
is
unlawful
and
its
rationale
for
not
doing
so
is
unlawful,
arbitrary,
and
capricious.
EPA
did
not
even
discuss
the
other
HAP
or
provide
any
explanation
for
its
failure
to
control
them.
EPA
argues
that
section
112(
n)
gives
it
discretion
on
which
HAP
to
regulate
for
power
plants.
EPA
ignores
section
112(
d)
and
misreads
section
112(
n).
Section
112(
n)
does
not
provide
any
exceptions
from
the
section
112(
d)
requirements.
EPA
does
not
identify
any
statutory
support
for
its
interpretation
of
section
112(
n).

°
Many
commenters
stated
that
the
proposals
fail
to
address
over
60
other
HAP
like
As,
Cr,
dioxin,
and
acid
gases
(
HF
and
HCl).
According
to
Commenters
OAR­
2002­
0056­
2219
and
­
2198,
EPA
must
regulate
all
HAP
from
the
affected
sources
for
three
reasons.
(
1)
EPA
regulated
all
HAP
from
industrial
boilers
under
subpart
DDDD
and
there
is
little
or
no
difference
in
coal­
fired
industrial
boilers
and
coal­
fired
utility
units.
EPA
must
explain
this
discrepancy.
(
2)
The
study
required
under
112(
n)
was
not
restricted
to
only
Hg
and
Ni
­­
all
HAP
were
to
be
assessed.
(
3)
Use
of
section
112(
d)
requires
addressing
all
HAP
emitted
from
utility
units.
Commenter
2889
adds
that
Hg
and
Ni
controls
would
provide
control
of
other
HAP,
increasing
the
cost
effectiveness.
Commenter
OAR­
2002­
0056­
3326
adds
that
a
number
of
HAP
emitted
from
power
plants
exceed
health
benchmarks,
as
evidenced
by
toxic
air
monitors
operated
over
the
past
3
years.

°
Commenter
OAR­
2002­
0056­
3437
disagrees
with
EPA's
interpretation
of
section
112(
n)(
1)(
A)
that,
once
EPA
determines
it
must
regulate
Hg,
it
is
not
required
to
regulate
any
other
HAP.
The
plain
language
of
subsection
(
n)
is
that
EPA
is
to
regulate
under
section
112
 
after
considering
the
results
of
the
study
required
by
this
subsection.
Subsection
112(
n)
refers
to
the
larger
section
112.,
which
requires
regulation
of
all
HAP,
not
just
the
most
significant
one.
The
commenter
believes
EPA's
decision
not
to
address
other
toxic
pollutants
is
not
consistent
with
section
112
and
rules
EPA
has
promulgated
for
other
industries
and
that
the
1998
Utility
RTC
does
not
support
EPA's
position.
EPA
states
that
the
study
indicates
that
there
are
no
non­
Hg
or
non­
Ni
HAP
emissions
that
warrant
regulation
and
makes
a
finding
that
the
uncertainties
are
so
great
that
regulation
of
these
pollutants
do
not
pose
a
health
risk.
The
Utility
RTC
specifically
says
that
the
report
does
not
make
a
determination
on
whether
to
control
HAP
emissions,
As
and
Cr
contribute
most
to
the
inhalation
cancer
risks,
The
MIR
from
all
HAP
are
4
in
1
million,
and
further
research
­
16­
is
needed
to
assess
inhalation
risk.
The
December
2000
finding
said
that
As
and
Cr
were
also
of
potential
concern
for
carcinogenic
effects.
Also,
EPA's
1996
National
Air
Toxics
Assessments
predicted
median
concentrations
of
As,
Cd,
and
Cr
n
numerous
counties
well
over
1
in
1
million.
Utilities
account
for
the
majority
of
these
emissions.
Chromium
is
the
most
significant
HAP
in
Indiana.
The
commenter
supports
additional,
refined
risk
assessment
before
EPA
determined
that
other
HP
do
not
pose
a
risk.

Response:

The
Administrator
today
signed
a
final
rule
titled
Revision
of
December
2000
Regulatory
Finding
on
the
Emissions
of
Hazardous
Air
Pollutants
from
Electric
Utility
Steam
Generating
Units
and
the
Removal
of
Coal­
and
Oil­
fired
Electric
Utility
Steam
Generating
Units
from
the
Section
112(
c)
list.
The
effect
of
that
final
rule
is
to
revise
EPA's
finding
that
it
is
appropriate
and
necessary
to
regulate
coal­
and
oil­
fired
Utility
Units
under
CAA
section
112
and
to
remove
electric
utility
steam
generating
units
for
the
112(
c)
list
of
source
categories.
As
a
result,
oil­
and
coal­
fired
Utility
Units
are
no
longer
subject
to
regulation
under
CAA
section
112
and
commenters
comments
are,
therefore,
moot.
The
EPA,
nevertheless,
disagrees
with
the
commenters'
contention
that
section
112(
n)(
1)(
A)
does
not
provide
EPA
with
the
authority
to
only
establish
regulations
for
those
hazardous
air
pollutants
for
which
it
determines
that
it
is
appropriate
to
do
so
were
it
finalizing
a
CAA
section
112
rule
for
all
of
the
reasons
explained
in
the
preamble
to
the
January
30,
2004
proposed
rule.
If
EPA
was
proceeding
with
a
CAA
section
112
rule,
that
rule
would
be
limited
to
regulating
mercury
emissions
from
coal­
fired
Utility
Units
for
the
following
reasons.

In
the
study
required
by
CAA
section
112(
n)(
1)(
A),
and
detailed
in
the
RtC,
EPA
identified
67
HAP
as
potentially
being
emitted
by
Utility
Units.
Based
on
a
screening
assessment
designed
to
prioritize
HAP
for
further
evaluation,
EPA
identified
14
HAP
as
priority
for
further
evaluation.
Of
the
14
HAP
identified
for
further
evaluation,
12
HAP
(
As,
beryllium
(
Be),
Cd,
Cr,
manganese,
Ni,
HCl,
HF,
acrolein,
dioxins,
formaldehyde,
and
radionuclides)
were
identified
for
further
study
based
on
potential
for
inhalation
exposure
and
risks.
Four
of
those
12
HAP
(
As,
Cd,
dioxins,
and
radionuclides)
plus
Hg
and
lead
(
Pb)
were
considered
priority
for
multipathway
exposure.
Of
those
six
HAP,
four
(
As,
Hg,
dioxins,
and
radionuclides)
were
identified
as
the
highest
priority
to
assess
for
multipathway
exposure
and
risks.
The
other
53
HAP
were
not
evaluated
beyond
the
screening
assessment.

In
evaluating
the
potential
for
inhalation
exposure
and
risks
for
the
12
HAP
identified
through
the
screening
assessment
as
priority
for
that
purpose,
EPA
estimated
the
high­
end
inhalation
cancer
risk
for
each
HAP
identified
as
a
carcinogen
and
the
high­
end
inhalation
noncancer
risks
for
the
remaining
HAP
for
both
coal­
and
oil­
fired
Utility
Units
in
2010.
That
evaluation
indicated
that
there
was
no
maximum
individual
risk
(
MIR)
for
cancer
greater
than
1
x
10­
6
for
Be,
Cd,
dioxin,
and
Ni
emissions
from
coal­
fired
Utility
Units
and
for
Be,
Cd,
and
dioxin
emissions
from
oil­
fired
Utility
Units.
With
regard
to
dioxins,
the
RtC
specifically
concluded
that
the
quantitative
exposure
and
risk
results
did
not
conclusively
demonstrate
the
existence
of
health
risks
of
concern
associated
with
inhalation
exposures
to
utility
emissions
on
a
national
scale
or
­
17­
from
any
actual
individual
utility.
The
RtC
thus
indicates
that
inhalation
of
Be,
Cd,
and
dioxin
emissions
from
Utility
Units
are
not
of
significant
concern
from
a
public
health
standpoint
because
such
exposure
does
not
present
a
MIR
for
cancer
greater
than
1
x
10­
6.
With
regard
to
Pb
emissions,
EPA
found
that
emission
quantities
and
inhalation
risks
were
relatively
low
and,
therefore,
decided
not
to
conduct
future
evaluations
of
multipathway
exposures
to
lead
resulting
from
Utility
Unit
emissions.
For
As,
EPA
concluded
that
there
were
several
uncertainties
associated
with
both
the
cancer
risk
estimates
and
the
health
effects
data
such
that
further
analyses
were
needed
to
characterize
the
inhalation
risks
posed
by
As
emissions
from
Utility
Units.
The
inhalation
exposure
assessment
did
not
identify
any
exceedences
of
the
health
benchmarks
(
e.
g.,
RfCs)
for
HCl
or
HF,
thus
indicating
that
Utility
Unit
emissions
of
those
HAP
did
not
pose
a
significant
public
health
concern.

The
EPA
erred
in
the
December
2000
Regulatory
Determination
to
the
extent
that
its
appropriate
finding
for
coal­
fired
Utility
Units
was
based,
in
any
way,
on
hazards
to
public
health
or
the
environment
arising
from
emissions
of
non­
Hg
HAP
from
coal­
fired
Utility
Units.
Based
on
the
information
before
it
at
the
time,
EPA
could
not
have
reasonably
concluded
that
coal­
fired
Utility
Unit
non­
Hg
HAP
emissions
presented
a
hazard
to
public
health.
In
addition,
as
stated
above,
EPA
should
not
have
considered
environmental
effects
in
the
December
2000
Regulatory
Determination's
consideration
of
whether
it
was
appropriate
to
regulate
HAP
emissions
from
coalfired
Utility
Units
under
CAA
section
112.

In
the
December
2000
Regulatory
Determination,
EPA
indicated
that
there
were
a
few
metallic
HAP
(
e.
g.,
Cr
and
Cd)
which
were
of
potential
concern
for
carcinogenic
effects,
but
stated
that
"
the
results
of
the
risk
assessment
(
performed
in
conjunction
with
the
RtC)
indicate
that
cancer
risks
are
not
high".
The
EPA
acknowledged,
however,
that
the
cancer
risks
were
not
low
enough
to
eliminate
those
metals
as
a
potential
concern
for
public
health.
This
later
statement,
at
least
as
it
pertains
to
Cd,
is
at
odds
with
the
results
of
the
risk
assessment
set
forth
in
the
RtC
and
discussed
above.
In
the
RtC,
EPA
determined
that
there
was
no
MIR
for
cancer
greater
than
1
x
10­
6
due
to
inhalation
of
Cd
emissions
from
Utility
Units.
In
the
Proposed
Rule,
EPA
stated
that
although
it
recognized
the
existence
of
uncertainties
with
regard
to
the
data
and
information
obtained
prior
to
the
December
2000
Regulatory
Determination
regarding
potential
hazards
to
public
health
resulting
from
Utility
Unit
emissions
of
non­
Hg
metallic
HAP,
the
Agency
believed
that
the
uncertainties
associated
with
those
emissions
were
so
great
that
it
was
not
appropriate
to
regulate
them
at
that
time
because
they
do
not
pose
a
hazard
to
public
health
that
warrants
regulation.
The
EPA
continues
to
believe
that
had
it
properly
accounted
for
the
uncertainties
regarding
the
data
and
information
on
potential
hazards
to
public
health
resulting
from
Utility
Unit
emissions
of
non­
Hg
metallic
HAP
in
making
the
December
2000
appropriate
finding
it
would
have
concluded
that
it
was
not
appropriate
to
regulate
such
emissions
because
they
do
not
cause
a
hazard
to
public
health.
The
EPA
has
not
discovered
any
new
information
on
hazards
to
public
health
arising
from
such
emissions
that
invalidates
this
conclusion,
either
through
its
own
efforts
or
in
response
to
the
Proposed
Rule.

In
the
December
2000
Regulatory
Determination,
EPA
also
identified
dioxins
as
being
of
­
18­
potential
concern
and
indicated
that
they
may
be
evaluated
further
during
the
regulatory
development
process.
The
EPA
did
not,
however,
indicate
that
those
concerns
rose
to
a
level
that
warranted
regulation
of
dioxins.
Thus,
EPA
did
not
conclude,
and
could
not
have
concluded,
based
on
the
record
before
it
at
the
time
of
the
December
2000
Regulatory
Determination
that
it
was
appropriate
to
regulate
coal­
fired
Utility
Unit
HAP
emissions
under
section
112
of
the
CAA
on
the
basis
of
dioxin
emissions.
In
the
Proposed
Rule
EPA
stated
that
while
it
intended
to
continue
to
study
dioxins
in
the
future,
the
RtC
and
the
information
EPA
had
obtained
since
finalizing
the
RtC
revealed
no
public
health
hazards
reasonably
anticipated
to
occur
as
a
result
of
emissions
of
dioxins
by
Utility
Units.
As
is
the
case
with
non­
Hg
metallic
HAP,
EPA
has
neither
discovered
information
on
hazards
to
public
health
arising
from
Utility
Unit
emissions
of
dioxins
based
on
its
own
efforts,
nor
received
such
information
in
response
to
the
Proposed
Rule.
The
EPA
therefore
concludes
that
its
appropriate
finding
in
December
2000
lacked
foundation
because
it
could
not
have
reasonably
concluded
that
the
level
of
remaining
utility
dioxin
emissions
results
in
hazards
to
public
health.

In
the
December
2000
Regulatory
Determination,
EPA
identified
emissions
of
HCl
and
HF
as
being
of
potential
concern
and
indicated
that
such
emissions
may
be
evaluated
further
during
the
regulatory
development
process.
The
EPA
did
not,
however,
indicate
that
it
believed
that
it
was
appropriate
to
regulate
such
emissions,
under
section
112
or
otherwise.
As
indicated
in
the
Proposed
Rule,
EPA
did
in
fact
further
evaluate
Utility
Unit
emissions
of
HCl
and
HF.
That
modeling
indicates
that
individuals
are
not
exposed
to
acid
gas
emissions
from
Utility
Units
at
concentrations
which
pose
hazards
to
public
health.
EPA
has
neither
discovered
information
on
hazards
to
public
health
arising
from
Utility
Unit
emissions
of
acid
gases
based
on
its
own
efforts,
nor
received
such
information
in
response
to
the
Proposed
Rule.
EPA
therefore
concludes
that
its
appropriate
finding
in
December
2000
lacked
foundation
because
the
level
of
remaining
utility
acid
gas
emissions
does
not
result
in
hazards
to
public
health.

For
the
reasons
stated
above,
EPA
finds
that
it
could
not
reasonably
have
concluded
that
it
was
appropriate
to
regulate
coal­
fired
Utility
Units
under
section
112
due
to
emissions
of
non­
Hg
HAP
based
on
the
record
before
it
at
the
time
of
the
December
2000
Regulatory
Determination.
The
EPA
further
finds
that
it
has
not
itself
discovered
any
information
which
would
support
the
conclusion
that
it
is
appropriate
to
regulate
non­
Hg
HAP
emissions
by
coal­
fired
Utility
Units
under
CAA
section
112
subsequent
to
the
December
2000
Regulatory
Determination,
nor
has
it
received
any
such
information
in
response
to
the
January
2004
Proposed
Rule,
the
March
2004
Supplemental
Notice
or
the
December
2004
Notice
of
Data
Availability.
Finally,
EPA
finds
that
it
should
never
have
considered
potential
environmental
effects
in
determining
whether
it
was
appropriate
to
regulate
coal­
fired
Utility
Units
under
section
112.
The
EPA,
therefore,
finds
that,
based
on
the
record
before
it
at
the
time,
it
was
in
error
in
determining
that
it
was
appropriate
to
regulate
coal­
fired
Utility
Unit
HAP
emissions
under
section
112
to
the
extent
that
the
determination
was
based
in
any
way
on
the
hazards
to
public
health
of
non­
Hg
HAP
emissions
or
on
environmental
effects
resulting
from
such
emissions.

In
determining
whether
it
is
appropriate
and
necessary
to
regulate
Utility
Unit
HAP
­
19­
emissions
under
section
112,
the
threshold
question
is
whether
it
is
appropriate
to
regulate
such
emissions
at
all.
Where,
as
here,
EPA
cannot
reasonably
conclude
that
it
is
appropriate
to
regulate
such
emissions,
it
should
never
have
reached
the
question
of
whether
it
is
necessary
to
regulate
such
emissions
under
section
112,
or
elsewhere.
In
any
event,
even
if
EPA
could
have
reasonably
concluded
that
it
was
appropriate
to
regulate
non­
Hg
HAP
emissions
from
coal­
fired
Utility
Units,
it
would
not
have
been
reasonable
for
the
Agency
to
find
that
it
was
necessary
to
regulate
such
emissions
under
section
112
since,
as
discussed
above,
it
should
have
realized
that
there
was
an
available
alternative
mechanism,
i.
e.,
section
111,
for
regulating
such
emissions
had
it
been
appropriate
to
do
so.

Comment:

These
commenters
believe
EPA
correctly
decided
not
to
regulate
HAP
emissions
other
than
Hg
and
Ni
from
Utility
Units,
EPA
should
only
regulate
Hg,
and/
or
EPA
should
not
regulate
Ni
emissions
from
oil­
fired
units.

°
Commenter
OAR­
2002­
0056­
3537
notes
that
EPA
appropriately
recognizes
that
parts
of
its
December
2000
finding
were
overbroad
and
could
not
reasonably
have
been
made,
based
on
the
record
before
it
in
December
2000.
EPA
recognizes
that
its
determination
could
be
interpreted
to
suggest
that
all
HAP
emissions
from
coal
and
oil­
fired
Utility
Units
pose
serious
public
health
hazards.
However,
in
the
preamble
to
the
Hg
Rule,
EPA
admits
that
it
could
not
reasonably
have
reached
such
a
conclusion
based
on
the
record
before
it
at
the
time
of
the
finding,
which,
according
to
EPA,
support
only
a
finding
that
emissions
of
Hg
and
Ni
warrant
regulation.
EPA
notes
that
nothing
in
the
utility
study
or
information
obtained
by
EPA
following
such
study
(
such
as
the
NAS
Study)
supports
the
proposition
that
EPA
should
address
HAP
emissions
from
Utility
Units
other
than
emissions
of
Hg
and
Ni.
The
commenter
notes
that
EPA
also
recognizes
that
its
conclusion
that
emissions
of
HAP
from
Utility
Units
result
in
serious
environmental
hazards
also
cannot
be
supported
by
the
record.
The
commenter
submits
first
and
foremost,
CAA
section
112(
n)(
1)(
A),
focuses
solely
on
hazards
to
public
health,
not
the
environment.
Second,
the
utility
study
itself
expressly
notes
that
the
ecological
impacts
associated
with
HAP
from
utility
units
were
not
examined,
because
such
impacts
were
beyond
the
scope
of
the
study
mandated
by
section
112(
n)(
1)(
A).
The
commenter
further
notes
therefore,
EPA
expressly
states
that:
""
the
most
...
[
it]
could
have
intended
to
state
in
the
December
2000
`
necessary'
finding
is
it
is
necessary
to
regulate
Hg
from
coal­
fired
Utility
Units
and
Ni
from
oil­
fired
Utility
Units
because
the
implementation
of
other
requirements
under
the
CAA
will
not
adequately
address
the
serious
public
health
hazards
arising
from
such
emissions
or
the
environmental
hazards
associated
with
Hg."
The
commenter
submits
that
this
finding
if
properly
made
is
sufficient
to
support
the
regulation
of
Hg
emissions
from
coal­
fired
Utility
Units
under
section
112.

°
According
to
Commenter
OAR­
2002­
0056­
2422,
non­
Hg
HAP
should
not
be
regulated.
EPA's
authority
under
CAA
sections
112(
c)
and
(
d)
is
limited
to
regulating
Hg
emissions
from
coal­
fired
plants.
This
limitation
results
from
the
unique
way
that
Congress
chose
to
­
20­
treat
electric
utility
steam
generating
units
under
section
112
of
the
Clean
Air
Act.

°
Commenter
OAR­
2002­
0056­
3556,
­
2911
states
that
EPA
has
correctly
decided
not
to
regulate
HAP
emissions
other
than
Hg
and
Ni
from
Utility
Units.
In
its
December
14,
2000
regulatory
decision,
EPA
concluded
that
Hg
from
coal­
fired
plants
is
the
HAP
of
greatest
potential
concern,
with
additional
research
and
monitoring
being
needed.
The
commenter
points
out
that
EPA
noted
that
Ni
emissions
from
oil­
fired
plants
were
of
potential
concern,
but
that
significant
uncertainties
exist
pertaining
to
the
form
of
Ni
emitted.
The
commenter
also
points
out
that
EPA
stated
that
As
and
a
few
other
metals,
such
as
Cr
and
Cd,
may
be
of
potential
concern
for
carcinogenic
effects,
and
that
dioxins,
HCl,
and
HF
are
of
potential
concern,
and
all
would
require
more
study.
EPA
added
that
the
other
HAP
studied
in
the
risk
assessment
do
not
appear
to
be
of
concern
for
public
health,
based
on
the
available
information.
The
commenter
also
points
out
that
in
the
preamble
to
the
rule,
EPA
does
not
suggest
that
any
non­
Hg
HAP,
emitted
by
Utility
Units,
is
a
public
health
concern,
nor
has
it
offered
any
factual
evidence
to
support
such
a
conclusion.
The
commenter
states
that,
consequently,
the
rulemaking
record
does
not
establish
any
public
health
concern
from
power
plant
emissions
of
non­
Hg
HAP.
The
commenter
further
states
that
until
such
a
factual
showing
exists,
EPA
does
not
have
legal
authority
to
regulate
those
HAP,
under
CAA
section
112(
n)(
1)(
A).
The
commenter
states
that,
consequently,
the
rulemaking
record
neither
establishes
nor
supports
a
public
health
concern
for
the
regulation
of
other
HAP.

°
Commenter
OAR­
2002­
0056­
2830
states
that
EPA
should
regulate
only
Hg
as
a
coal­
fired
utility
boiler
HAP.
EPA
and
EPRI
studies
have
demonstrated
that
other
coal­
fired
utility
HAP
emissions
do
not
pose
public
health
risk.

°
Commenter
OAR­
2002­
0056­
2835
stated
that
it
is
appropriate
to
focus
any
air
regulatory
program
for
electric
utilities
solely
on
emissions
of
Hg
and
Ni
given
that
these
are
the
pollutants
of
greatest
concern.
No
other
outcome
is
legally
permissible
based
on
the
information
in
the
rulemaking
record,
which
only
supports
setting
limits
for
those
pollutants
of
greatest
concern.
EPA
correctly
states
that
the
information
collected
on
emissions
of
other
HAP
is
inconclusive.
CAA
section
112(
n)(
1)(
A)
requires
EPA
to
assess
the
public
health
hazards
posed
by
emissions
from
electric
utilities
and
regulate
these
sources
considering
the
results
of
the
study.
This
section
does
not
dictate
which
pollutants
EPA
must
regulate
independent
of
the
potential
health
risks;
instead,
EPA
must
consider
the
results
of
the
study.
Given
that
EPA's
study
points
to
Hg
emissions,
and
to
some
extent
Ni
emissions,
as
the
HAP
of
greatest
concern,
a
regulatory
program
addressing
only
these
pollutants
meets
the
statutory
requirements
of
section
112(
n)(
1)(
A).

°
Several
commenters
(
OAR­
2002­
0056­
2365,
­
2660,
­
2891,
­
3200,
­
3432)
support
EPA's
finding
that
non­
Hg
HAP
from
coal­
fired
power
plants
do
not
need
to
be
regulated.
CAA
section
112(
n)
directs
EPA
to
regulate
HAP
emissions,
if
appropriate
and
necessary,
based
on
health
effects.
EPA's
studies
have
found
no
need
to
control
non­
Hg
HAP
based
on
public
health
concerns,
and
the
agency
has
not
determined
that
such
controls
are
necessary.
­
21­
°
Commenter
OAR­
2002­
0056­
3445
notes
that
in
its
December
2000
regulatory
determination
(
65
FR
79824),
EPA
identified
only
Hg
as
the
pollutant
of
concern.
The
commenter
further
notes
that
EPA
collected
and
studied
Hg
data
in
the
ICR
and
the
working
group
process.
The
commenter
states
that
only
Hg
emissions
should
be
regulated.

°
Commenter
OAR­
2002­
0056­
3478
points
out
that
before
making
the
decision
to
include
coal­
and
oil­
fired
as
NESHAP
source
categories,
EPA
conducted
a
comprehensive
study
of
the
impacts
from
all
HAP
emitted
by
these
units.
The
commenter
notes
that
EPA
concluded
that
Hg
(
and
Ni
from
oil­
fired
units)
were
the
only
HAP
of
concern
for
the
coal­
fired
units.

Response:

The
Administrator
today
signed
a
final
rule
titled
Revision
of
December
2000
Regulatory
Finding
on
the
Emissions
of
Hazardous
Air
Pollutants
from
Electric
Utility
Steam
Generating
Units
and
the
Removal
of
Coal­
and
Oil­
fired
Electric
Utility
Steam
Generating
Units
from
the
Section
112(
c)
list.
The
effect
of
that
final
rule
is
to
revise
EPA's
finding
that
it
is
appropriate
and
necessary
to
regulate
coal­
and
oil­
fired
Utility
Units
under
CAA
section
112
and
to
remove
electric
utility
steam
generating
units
for
the
112(
c)
list
of
source
categories.
As
a
result,
oil­
and
coal­
fired
Utility
Units
are
no
longer
subject
to
regulation
under
CAA
section
112.
EPA
does,
however,
agree
with
the
commenters
that
Hg
is
the
only
pollutant
for
which
regulation
should
be
pursued.
Consequently,
the
Administrator
signed
another
final
rule
today
titled
Standards
of
Performance
for
New
and
Existing
Stationary
Sources:
Electric
Utility
Steam
Generating
Units.
That
rule
establishes
a
traditional
CAA
section
111(
b)
new
source
performance
standard
for
mercury
emissions
from
Utility
Units
and
provides
for
a
national
mercury
cap­
and­
trade
program
for
mercury
emissions
from
both
new
and
existing
Utility
Units
pursuant
to
CAA
section
111(
d).
The
new
rule
does
not
address
Ni
emissions
from
oil­
fired
Utility
Units
because
EPA
has
determined
that
regulation
of
Ni
emissions
from
oil­
fired
Utility
Units
is
not
necessary.

D.
Is
it
Appropriate
and
Necessary
to
Regulate
Oil­
fired
units
under
section
112
on
the
basis
of
Ni
Emissions.

Comment:

Several
industry
commenters
(
OAR­
2002­
0056­
2046,
­
2452,
­
2504,
­
2835,
­
2828,
­
2850,
­
2867,
­
2891,
­
2910,
­
2922,
­
3345,
­
3356,
­
3402,
­
3513,
­
4454)
contend
that
the
risk
posed
by
Ni
emissions
from
oil­
fired
units
is
negligible
and
does
not
justify
the
December
2000
regulatory
determination
that
it
is
appropriate
and
necessary
to
these
units.
The
commenters
contend:

°
The
EPA
risk
assessment
and
assumptions
in
the
Utility
RTC
greatly
overestimated
the
inhalation
risk
posed
by
Ni
emissions
from
oil­
fired
plants.
Although
EPA
acknowledged
that
there
was
significant
uncertainty
concerning
the
risks,
the
agency
overestimated
the
risks
from
oil­
fired
plants
assuming
that
50
percent
of
the
Ni
emitted
from
oil­
fired
plants
is
nickel
subsulfide
(
a
carcinogen),
but
then
admitted
in
the
report
that
the
data
available
indicated
less
­
22­
than
10
percent
of
Ni
emissions
as
nickel
subsulfide.
Recent
studies
(
University
of
North
Dakota
Energy
&
Environmental
Research
Center,
UNDEERC)
have
shown
that
the
amount
of
nickel
subsulfide
actually
emitted
from
oil­
fired
units
is
much
lower
(
nearing
or
at
zero)
than
originally
assumed
by
EPA.
Commenter
OAR­
2002­
0056­
4454
adds
that
recent
studies
by
Galbreath
in
2000
and
2004
show
that
the
Ni
species
in
oil­
fired
emissions
consist
of
soluble
nickel
sulfate
and
insoluble
nickel
oxide
­
­
nickel
subsulfide
is
simply
not
present,
and
would
not
be
expected
to
be,
given
its
instability
at
high
temperatures
and
with
excess
stoichiometry
of
oxygen.
If
there
is
near
zero
or
zero
nickel
subsulfide
being
emitted,
then
the
risks
of
Ni
emissions
are
near
zero
or
zero.
According
to
Commenter
OAR­
2002­
0056­
2046,
the
Carnot
and
University
of
Louisville
Nickel
Speciation
Program
April
1995
testing
of
Sites
127,
128,
129,
and
130
(
EPRI­
12288/
R016F989.
T)
and
EPRI
PISCES
Field
Chemical
Emissions
Monitoring
Project
Site
112
Emissions
Report
(
EPRI
TR­
105632/
9028­
03)
showed
that
sulfidic
nickel
compounds
generally
comprised
between
5
and
10
percent
of
total
Ni,
with
a
maximum
of
25
percent.
The
commenter
noted
that
with
the
exception
of
the
UNDEERC
study,
tests
were
conducted
for
nickel
sulfide,
not
nickel
subsulfide.
In
view
of
the
these
findings,
EPA
does
not
have
a
sufficient
basis
to
support
its
original
finding
that
regulation
of
oil­
fired
utility
units
is
appropriate
and
necessary
under
CAA
section
112(
n)(
1)(
A).
Commenter
OAR­
2002­
0056­
2912
agrees
that
EPA
should
rescind
the
regulatory
determination
for
oil­
fired
units
because
the
Utility
RTC
contains
faulty,
and
scientifically
unsupportable,
assumptions
regarding
the
carcinogenicity
of
Ni
emitted
from
oil­
fired
units.

°
Commenter
OAR­
2002­
0056­
2867
submits
that
no
studies
have
attributed
specific
health
effects
to
Ni
emissions
from
utility
units,
and
recent
work
suggests
that
speciation
data
supports
the
lack
of
any
viable
connection
between
such
emissions
and
any
arguable
health
effects.
The
commenter
asserts
that
EPA's
decision
to
regulate
Ni
from
oil­
fired
plants
likewise
is
not
substantiated.
EPA
admits
(
69
Fed.
Reg.
at
4658)
that
uncertainties
exist
with
respect
to
the
quantity
and
fate
of
the
Ni
emissions
from
oil­
fired
power
plants,
their
speciation,
and
that
there
are
no
reference
concentrations
that
can
be
related
to
specific
health
endpoints.
The
commenter
submits
that
in
sum,
there
is
a
lack
of
any
demonstrated
link
between
power
plant
emissions
and
inhalation
based
health
effects
risks
(
the
primary
human
exposure
route).
The
commenter
believes
that
given
these
limitations
EPA
does
not
have
a
sound
basis
for
regulating
Ni
emissions
from
oil­
fired
utility
units.
The
commenter
adds,
moreover,
EPA's
health
risk
assessment
for
oil­
fired
power
plant
Ni
emissions
is
keyed
to
what
is
believed
to
be
""
screening
level""
modeling
of
health
effects,
that
may
not
have
been
predicated
on
correct
assumptions
for
the
parameters
listed
above.
Previous
EPRI
conducted
modeling
appears
to
dispel
any
inhalation
risk
concerns,
the
principal
pathway
for
human
exposure.

°
Commenter
OAR­
2002­
0056­
3345
notes
that
an
EPRI
study
used
many
of
the
EPA's
emissions
data
and
risk
assessment
methods
but
concluded
that
cancer
inhalation
risks
are
less
than
one
in
one
million
for
all
utilities,
and
non­
cancer
inhalation
risks
are
well
below
Federal
threshold
levels
for
all
utilities.
Although
the
Utility
RtC
states
that
further
research
­
23­
is
needed
to
assess
the
inhalation
cancer
risks
especially
to
reduce
uncertainties
associated
with
the
Ni
risk
estimates,
EPA
appears
to
have
ignored
the
EPRI
research
and
the
Utility
RTC's
recommendations.
Despite
these
uncertainties
(
and
without
resolving
them),
EPA
determined
that
it
was
appropriate
and
necessary
to
regulate
Ni
emissions
from
oil­
fired
utility
units.

°
There
has
been
a
substantial
change
in
the
universe
of
affected
facilities
.
More
recent
operating
data
show
that
a
number
of
the
facilities
have
retired
or
reduced
their
use
of
residual
oil
since
EPA
performed
its
study.
Use
of
many
oil­
fired
generators
has
been
reduced
due
to
age
and/
or
high
fuel
costs.
According
to
one
commenter,
one
of
its
members
serving
Jacksonville
and
northeast
Florida
has
retired
all
of
its
inter­
city
heavy
oil­
fired
units
and
has
recovered
two
300
MW
units
at
the
rural
Northside
Generating
station.
The
member's
system
has
gone
from
11
oil­
fired
generators
(
approximately
1700
MW)
in
the
1980s
to
1
unit
(
approximately
500
MW)
today.
Thus,
there
may
no
longer
be
a
plant
that
contributes
to
a
MIR
of
cancer
of
more
than
one
in
one
million,
which
would
make
delisting
appropriate.
The
commenters
(
OAR­
2002­
0056­
2046,
­
2835,
­
2891,
­
2912,
­
3402,
­
3345)
recommend
that
EPA
revisit
the
question
of
whether
Ni
emissions
from
these
units
warrant
regulation
at
all.

°
Four
commenters
(
OAR­
2002­
0056­
2952,
­
3445,
­
3514,
­
4454)
stated
that
the
proposed
rule
for
Ni
emissions
from
oil­
fired
units
is
based
on
inadequate
data.

°
Several
commenters
(
OAR­
2002­
0056­
2850,
­
2915,
­
2929,
­
2948,
­
2952,
­
3345,
­
3514,
­
3556)
contend
that
EPA
has
no
jurisdiction
to
regulate
Ni
from
oil­
fired
plants
because
specific
health
concerns
associated
with
HAP
emissions
were
not
identified
when
the
agency
issued
original
regulatory
determination
in
December
2000.
The
evidence
in
the
rulemaking
record
fails
to
show
that
there
is
a
public
health
risk
associated
with
Ni
emissions
from
oil­
fired
units.
Commenter
OAR­
2002­
0056­
2952
states
that
EPA's
determination
that
it
was
"
appropriate
and
necessary"
to
regulate
Ni
emissions
from
oil­
fired
units
was
made
in
error
because
it
did
not
properly
reflect
the
lack
of
information
on
the
health
effects
from
Ni
emissions
from
oil­
fired
units.

Response:

Based
on
the
comments
received,
EPA
has
examined
recently
available
information
relating
to
both
the
number
of
oil­
fired
units
and
the
combinations
of
fuels
fired
in
such
units.
Based
on
that
examination,
EPA
believes
that
Ni
emissions
from
oil­
fired
Utility
Units
have
been
substantially
reduced
since
the
1998
Utility
RtC
through
a
combination
of
unit
closures
and
fuel
switching.
In
addition
to
the
information
provided
by
the
commenters,
EPA
analyzed
the
latest
information
provided
by
the
U.
S.
Department
of
Energy,
Energy
Information
Administration
(
DOE/
EIA),
particularly
with
regard
to
the
11
plants
identified
as
causing
the
greatest
risk.
The
11
oil­
fired
plants
identified
in
the
Utility
Study
as
having
a
cancer
maximum
individual
risk
of
greater
than
10­
6
based
on
Ni
emissions
were
comprised
of
42
individual
units.
Of
those
42
units,
­
24­
12
units
have
permanently
ceased
operation
or
are
out
of
service.
(
OAR­
2002­
0056­
2046
at
pp.
12
­
13;
OAR­
2002­
0056­
5998).
In
addition,
6
of
the
original
42
units
have
reported
to
the
U.
S.
Department
of
Energy
(
DOE)
that
their
fuel
mix
now
includes
natural
gas.
Earlier
reports
did
not
show
these
units
as
using
natural
gas
as
a
fuel.
(
OAR­
2002­
0056­
5998).
The
use
of
natural
gas
as
a
part
of
their
fuel
mix
would
decrease
the
Ni
emissions
from
these
6
units.
Similarly,
another
5
units
report
using
a
mix
of
natural
gas
and
distillate
oil
(
rather
than
residual
oil)
in
2003.
(
OAR­
2002­
0056­
5998).
Since
distillate
oil
contains
less
Ni
than
the
residual
oil
previously
burned
by
these
units,
it
is
reasonable
to
assume
that
these
units
currently
emit
less
Ni
than
was
previously
the
case.
Another
2
units
now
fire
a
residual
oil/
natural
gas
mixture
and
have
limited
their
residual
oil
use
through
permit
restrictions
to
no
greater
than
10
percent
of
the
fuel
consumption
between
April
1
and
November
15,
with
natural
gas
being
used
for
at
least
90
percent
of
total
fuel
consumption.
(
OAR­
2002­
0056­
2046
at
p.
13).
Finally,
five
units
have
effectively
eliminated
their
Hg
emissions
since
the
Utility
Study
by
switching
to
burning
natural
gas
exclusively.
(
OAR­
2002­
0056­
2046
at
pp.
12
­
13;
OAR­
2002­
0056­
5998).
Taken
as
a
whole,
these
changes
mean
that
30
of
the
original
42
units
identified
in
the
Utility
Study
have
taken
steps
to
effectively
reduce
or
actually
eliminate
their
Ni
emissions.
Of
the
original
11
plants
identified
in
the
Utility
Study,
only
2,
both
in
Hawaii,
have
units
for
which
actions
that
will
result
in
reduced
Ni
emissions
do
not
appear
to
have
been
taken.
(
OAR­
2002­
0056­
6871).
In
addition
to
the
closure
of
the
12
units
identified
as
being
of
potential
concern
in
the
Utility
Study,
there
has
been
a
steady
decrease
in
the
number
of
oil­
fired
Utility
Units
generally
over
the
past
decade
and
this
trend
is
likely
to
continue.
In
fact,
the
latest
DOE/
EIA
projections
(
OAR­
2002­
0056­
5999)
estimate
no
new
utility
oil­
fired
generating
capacity
and
decreasing
existing
oil­
fired
generating
capacity
through
2025,
with
an
additional
29.2
gigawatts
of
combined
oil­
and
natural
gas­
fired
existing
capacity
being
retired
by
2025.
Based
on
the
foregoing,
EPA
concludes
that
it
is
not
appropriate
to
regulate
oil­
fired
Utility
Units
under
section
112
because
we
do
not
anticipate
that
the
remaining
level
of
utility
Ni
emissions
will
result
in
hazards
to
public
health.

E.
EPA's
Authority
to
Regulate
HAP
from
Utility
Units
Under
CAA
Section
111.

Many
commenters
(
including
States
and
public
interest
groups)
stated
that
EPA
has
misconstrued
CAA
section
112(
n),
and
that
section
112
is
the
only
legal
authority
for
regulating
HAP.
(
OAR­
2002­
0056­
2108,
­
2330,
­
2332,
­
2823,
­
2575,
­
2823,
­
2880,
­
2871,
­
2878,
­
2889,
­
2920,
­
2924,
3393,
­
3394,­
3459).
According
to
these
commenters:

°
The
legislative
history
cited
by
EPA
does
not
support
its
position
(
OAR­
2002­
0056­
2823,
­
2920,
­
3459,
3393,
3394).
According
to
commenter
OAR­
2002­
0056­
2823,
EPA
attempts
to
find
support
for
its
interpretation
of
section
111(
d)
by
citing
a
conflict
where
none
exists
between
the
1990
House
and
Senate
amendments
to
section
111(
d)
in
1990.
Although
there
is
a
difference
in
the
two
versions,
the
language
does
not
affect
the
meaning
of
section
111(
d).
According
to
commenter
OAR­
2002­
0056­
2920,
both
amendments
clearly
preclude
regulation
of
Hg
and
Ni
under
CAA
section
111.
Commenter
OAR­
2002­
0056­
3459
gave
two
explanations
why
the
two
amendments
do
not
conflict
and
stated
that
both
amendments
reinforce
the
same
principle
 
EPA
can
not
use
CAA
section
111(
d)
to
regulate
HAP
except
­
25­
where
the
CAA
specifically
tells
EPA
to
do
so.
Even
if
they
did
conflict,
EPA
can
not
adopt
its
proposed
reconciliation
because
there
is
a
canon
of
statutory
interpretation
that
when
two
provisions
are
irreconcilably
conflicting,
the
last
provision
in
the
point
of
arrangement
(
in
this
case,
the
Senate
amendment)
must
control
(
Lodge
1858,
Am.
Fed.
of
Gov't
Employees
v.
Webb,
580
F.
2d
496,
510
(
D.
C.
1978).
Because
there
is
an
easy
reconciliation,
EPA
lacks
authority
to
adopt
an
alternative
interpretation
in
an
attempt
to
invent
new
regulatory
authority
to
control
HAP
under
section
111(
d)
beyond
the
requirements
of
section
129.
Because
this
authority
does
not
exist,
EPA
cannot
use
section
111(
d)
to
issue
standards
of
performance
for
HAP
from
existing
units.
Because
EPA
cannot
use
section
111(
d),
EPA's
claimed
authority
to
rescind
its
regulatory
determination
evaporates
and
regulation
under
section
112
remains
necessary
just
as
EPA
determined
in
December
2000.
Finally
the
commenter
asserts
that
EPA's
interpretation
of
the
conflicting
amendments
is
contrary
to
section
112(
b)(
6)
that
provides
that
pollutants
listed
under
CAA
section
112(
b)(
1)
are
not
subject
to
the
Prevention
of
Significant
Deterioration
("
PSD")
regulations
.

°
Sections
112(
c)(
6)
and
112(
d)(
7)
do
not
authorize
regulation
of
HAP
under
any
provision
of
the
CAA
except
section
112
(
OAR­
2002­
0056­
2878,
­
2920,
­
3459)
.
There
is
nothing
in
the
language
of
the
provisions,
legislative
history,
or
structure
of
the
CAA
to
support
EPA's
assertion.
EPA
does
not
identify
any
language
in
the
provisions
to
support
a
conclusion
(
only
their
assertion).
The
legislative
history
indicates
that
Congress
intended
EPA
to
regulate
HAP
only
under
section
112.
Commenter
3459
added
that
CAA
section
112(
d)(
7)
does
not
grant,
imply
or
contemplate
authority
to
regulate
HAP
emissions
under
any
other
section
other
than
112.
It
represents
a
prohibition
on
EPA
adopting
section
112
standards
that
diminish
or
replace
requirements
under
state
authorities
or
other
CAA
provisions.
The
commenter
gives
four
reasons
why
EPA's
reading
is
wrong
and
would
lead
to
absurd
results.

°
Statutory
authority
under
section
111(
d)
only
covers
standards
for
existing
sources
for
any
air
pollutant
for
which
air
quality
criteria
have
not
been
issued
or
which
is
not
on
the
list
of
criteria
pollutants
or
which
is
emitted
from
a
source
category
which
is
regulated
under
section
112.
Mercury
and
Ni
are
emitted
from
other
source
categories
regulated
under
section
112
(
e.
g.,
hazardous
waste
combustors).

°
EPA
misconstrues
CAA
section
111(
d).
Congress
did
not
intend
section
111(
d)
as
a
substitute
for
regulation
under
CAA
section
108
or
112.
Commenters
assert
that
section
111(
d)
is
a
backstop
provision,
requiring
state
regulation
of
existing
sources
if
emissions
from
new
sources
in
the
category
are
regulated
by
an
NSPS,
but
only
if
emissions
the
emissions
are
not
criteria
pollutants
regulated
under
CAA
sections
108­
110
and
that
HAP
be
regulated
under
section
112.
Regulation
under
CAA
section
111(
d)
is
unavailable
(
OAR­
2002­
0056­
2823).

°
EPA
has
no
authority
to
regulate
HAP
emissions
from
electric
utility
unit
or
to
establish
a
Hg
­
26­
cap
and
trade
program
under
CAA
section
111(
d).
Section
112(
n)
clearly
states
that
EPA
must
regulate
electric
utility
steam
generating
units
under
this
section
(
i.
e.,
112),
not
this
subsection.
Subsections
112(
d),
112(
f),
and
112(
h)
are
the
only
authorities
under
section
112
under
which
EPA
may
regulate
HAP
emissions.
Congressional
intent
to
regulate
Hg
emissions
under
section
112
is
clear
(
see
Chevron
USA
v.
NRDC,
467
US
837
(
1984).
(
OAR­
2002­
0056­
2330,
­
2332,
­
2871,
­
2880,
­
2889,
­
2924).

°
Commenter
OAR­
2002­
0056­
2920
states
that
even
if
the
legislative
history
cited
by
EPA
in
support
of
its
proposal
to
regulate
under
CAA
section
111
were
relevant,
it
does
not
support
rescinding
the
regulatory
finding.
Based
on
EPA's
construction
of
CAA
section
111(
d),
commenter
OAR­
2002­
0056­
2823
states
that
the
actual
listing
under
section
112(
c)
precludes
EPA
from
requiring
state
regulation
of
the
source
category
under
section
111(
d).
EPA's
determination
that
it
can
regulate
under
section
111(
d)
because
it
erred
in
the
source
category
listing
under
CAA
section
112(
c)
is
transparent
and
has
no
foundation
in
statutory
language
or
legislative
intent.

°
Thirteen
U.
S.
Senators
and
Congressmen
states
that
none
of
the
proposals
is
legally
supportable
under
the
Clean
Air
Act
and
each
violates
Congressional
intent
that
EPA
shall
regulate
HAP
under
section
112.
These
officials
urge
EPA
to
repropose
a
legally
defensible
and
scientifically
supportable
MACT
rule
under
section
112.
If
finalized
in
2005,
the
MACT
rule
will
be
more
than
3
years
late
and
they
do
not
wish
to
see
any
further
delay
in
fulfilling
the
requirements
of
section
112.
[
2836].

Response:

We
disagree
with
the
commenters.
For
all
of
the
reasons
stated
in
the
final
rule
titled
Revision
of
December
2000
Regulatory
Finding
on
the
Emissions
of
Hazardous
Air
Pollutants
from
Electric
Utility
Steam
Generating
Units
and
the
Removal
of
Coal­
and
Oil­
fired
Electric
Utility
Steam
Generating
Units
from
the
Section
112(
c)
list,
EPA
believes
that
it
has
authority
to
regulate
HAP
from
Utility
Units
under
section
111(
d)
of
the
Act.
The
commenters
do
not
dispute
that
both
the
House
and
the
Senate
enacted
different
amendments
to
section
111(
d)
in
1990.
Nor
do
they
dispute
that
the
language
of
the
two
amendments
differ.
EPA
disagrees
with
the
commenter
that
asserts
that
the
language
of
the
two
different
amendments
to
section
111(
d)
does
not
affect
the
meaning
of
section
111(
d).
The
language
of
the
amendments,
as
explained
in
the
final
rule,
are
different
and
commenters'
attempts
to
argue
to
the
contrary
lack
foundation.

In
section
111(
d),
EPA
is
confronted
with
the
highly
unusual
situation
of
an
enacted
bill
signed
by
the
President
that
contains
two
different
and
inconsistent
amendments
to
the
same
statutory
provision.
Neither
we,
nor
commenters,
have
identified
a
canon
of
statutory
construction
that
addresses
the
specific
situation
with
which
we
are
now
faced,
which
is
how
to
interpret
two
different
amendments
to
the
exact
same
statutory
provision
in
a
final
bill
that
has
been
signed
by
the
President.
The
canon
of
statutory
construction
that
calls
for
harmonizing
conflicting
statutory
provisions,
where
possible,
and
adopting
a
reading
that
gives
some
effect
to
both
provisions
is
not
­
27­
controlling
here
because
that
canon
applies
where
two
provisions
of
a
statute
are
in
conflict,
not
where
two
amendments
to
the
same
statutory
provision
are
in
conflict.
Similarly,
the
canon
of
statutory
construction
that
provides
that
where
there
is
a
conflict
between
two
provisions
in
a
statute,
the
last
provision
in
point
of
arrangement
controls
does
not
apply,
where,
as
here,
the
conflict
is
between
two
different
amendment
to
the
same
statutory
provision,
as
opposed
to
two
entirely
different
provisions
of
a
statute.
In
addition,
application
of
this
rule
conflicts
with
the
legislative
history
discussed
in
the
final
rule,
which
further
supports
EPA's
interpretation
of
the
conflicting
amendments
to
section
111(
d).

Moreover,
most
of
commenters'
arguments
hinge
on
the
assertion
that
their
interpretation
or
attempt
at
harmonizing
the
amendments
is
a
reasonable
one.
The
question,
however,
is
not
whether
the
commenters
have
identified
a
reasonable
construction
of
the
Act,
but
whether
EPA's
construction
is
permissible.
We
believe
that
our
construction
of
the
Act
is
permissible
and
consistent
with
the
legislative
history.

In
assessing
whether
to
revise
the
December
2000
"
necessary"
finding,
it
is
reasonable
to
look
to
whether
CAA
section
111
constituted
a
viable
alternative
authority
for
regulating
utility
HAP
emissions
prior
to
the
December
2000
finding.
The
answer
is
yes
and
therefore
under
our
proposed
interpretation
of
the
conflicting
amendments,
we
could
have
regulated
HAP
from
Utility
Units
under
section
111(
d).
We
listed
coal­
and
oil­
fired
Utility
Units
under
section
112(
c)
in
December
2000
based
solely
on
our
appropriate
and
necessary
finding.
That
finding
lacks
foundation
and,
recent
information,
confirms
that
it
is
neither
appropriate
nor
necessary
to
regulate
Utility
Units
under
CAA
section
112.
We
should
have
recognized
prior
to
the
December
2000
finding
that
section
111
constituted
a
viable
authority
for
regulating
utility
HAP
emissions
and
therefore
should
have
never
listed
Utility
Units
on
the
Section
112(
c)
list.

Finally,
commenters
argue
that
EPA
cannot
rely
on
section
111(
d)
to
regulate
HAP,
except
where
Congress
specifically
tells
it
do
so,
as
in
section
129.
EPA
disagrees.
Section
129
is
another
provision
of
the
Act,
in
which
Congress
treated
a
particular
source
category
in
a
unique
way.
Section
129,
like
section
112(
n)(
1)(
A),
are
both
specifically
tailored
provisions
to
specific
source
categories.
Congress
provided
different
treatment
for
these
two
source
categories,
but
that
does
not
render
our
interpretation
of
the
conflicting
amendments
 
that
EPA
can
regulate
HAP
under
section
111(
d)
is
such
HAP
are
emitted
from
facilities
that
are
not
part
of
a
source
category
regulated
under
section
112
 
invalid.
Commenters
also
rely
on
CAA
section
112(
n)(
5),
which
directs
EPA
to
study
hydrogen
sulfide,
which
is
not
a
HAP,
and
to
develop
a
control
strategy
to
protect
public
health
"
using
authorities,
such
as
sections
7411
of
this
title
and
this
section."
That
provision
cites
section
111,
but
it
also
refers
to
other
authorities,
such
as
section
111
and
112.
Section
112(
n)(
1)(
A)
is
framed
by
reference
to
the
requirements
of
the
Act.
It
does
not
reference
section
111,
but
the
fact
that
section
112(
n)(
5)
does,
as
an
example,
does
not
mean
that
EPA
cannot
regulate
HAP
under
section
111(
d).

Contrary
to
commenters'
assertions,
CAA
section
112(
b)(
6)
can
more
readily
be
viewed
as
demonstrating
that
Congress
was
aware
of
how
to
instruct
EPA
not
to
regulate
HAP
emission
under
­
28­
other
sections
of
the
Act
when
it
intended
to
do
so.
Since
there
is
not
a
similar
prohibition
in
section
112(
b)
regarding
regulations
under
CAA
section
111,
it
is
reasonable
to
assume
that
Congress
did
not
intend
to
preclude
EPA
from
regulating
HAP
emissions
under
that
section
in
appropriate
circumstances.
Similarly,
the
fact
that
Congress
specifically
authorized
EPA
to
use
its
authorities
under
section
111,
as
well
as
section
112,
in
developing
and
implementing
any
necessary
control
strategy
for
emissions
of
hydrogen
sulfide,
which
is
not
a
HAP,
should
not
be
read
as
precluding
EPA
from
regulating
HAP
emissions
under
section
111
when
EPA
determines
that
it
is
appropriate
to
do
so.

Comment:

Commenter
OAR­
2002­
0056­
2867
stated
that
EPA
has
correctly
harmonized
these
conflicting
statutory
provisions,
and
interpreted
them
in
a
way
that
effectuates
the
purposes
of
the
statute
as
whole.

Response:

EPA
agrees
with
this
commenter.

3.0
EPA's
PROPOSAL
TO
REMOVE
COAL­
AND
OIL­
FIRED
UTILITY
UNITS
FROM
THE
CAA
SECTION
112(
c)
LIST
2000
Many
commenters
disagreed
that
EPA
has
authority
to
remove
coal­
and
oil­
fired
Utility
Units
from
the
section
112(
c)
list
without
following
the
criteria
in
section
112(
c)(
9).
(
OAR­
2002­
0056­
1327,
1836,
2010,
2108,
2110,
2173,
2330,
­
2332,
­
2823,
­
2519,
­
2575,
2660,
­
2823,
­
2880,
2836,
­
2871,
­
2878,
­
2889,
2919,
­
2920,
­
2924,
3393,
3449,
­
3394,­
3459,
3552,
4139.]

°
EPA's
proposal
contravenes
the
legally
valid
and
correct
regulatory
determination
of
December
2000.
The
regulatory
determination
followed
Congressional
intent
of
regulation
under
section
112.
The
1998
NRDC
settlement
agreement
also
requires
this.
EPA
has
no
basis
for
reversing
this
determination.
Since
2000,
no
other
CAA
requirements
have
been
imposed
and
EPA
has
not
performed
a
new
study
or
otherwise
produced
new
information
of
diminished
hazard.
In
fact,
the
bulk
of
scientific
evidence
since
2000
justifies
more
stringent
regulation
of
Hg
and
other
HAP
from
these
sources.
Therefore,
EPA
can
not
conclude
that
"
after
considering
the
results
of
the
[
1998]
study"
it
is
not
longer
necessary
to
control
utility
emissions
under
section
.
Once
a
source
category
is
listed
under
section
112(
c),
which
it
did
in
December
2000,
it
cannot
delist
the
industry
unless
it
follows
the
process
in
section
112(
c)(
9).
EPA
can
not
do
this
because
the
facts
do
not
support
a
determination
that
no
coal
or
oil­
fired
plant
emits
HAP
at
levels
low
enough
that
(
1)
the
emissions
pose
no
lifetime
risk
of
cancer
greater
than
1
in
1
million,
(
2)
the
emissions
do
not
exceed
levels
adequate
to
protect
public
health
with
an
ample
margin
of
safety,
and
(
3)
no
adverse
environmental
effect
will
result
from
emissions
from
any
powerplant.
EPA's
attempt
to
endrun
these
requirements
­
29­
is
unacceptable.
(
OAR­
2002­
0056­
2836)

°
Commenter
2575
states
that
if
EPA
wants
the
regulatory
finding
to
disappear,
it
must
make
a
formal
finding
that
Hg
emissions
from
coal­
fired
power
plants
do
not
have
an
adverse
impact
on
human
health
and
therefore,
it
is
not
necessary
to
regulate
under
section
112.
Nowhere
does
(
or
could)
EPA
deny
the
severe
human
and
environmental
effects
of
Hg
contamination
on
waterways
and
consequential
dangers
to
public
health.
The
word
"
necessary"
in
section
112(
n)(
1)(
A)
means
that
EPA
must
regulate
Hg
emissions
under
section
112
if
the
public
health
impacts
require
such
regulation.
The
legislative
history
of
section
112(
n)
supports
this
position.

°
According
to
Commenter
2823,
EPA
tries
to
avoid
regulation
under
section
112
by
arguing
that
the
December
2000
regulatory
determination
was
without
proper
foundation.
Based
on
that
argument,
EPA
claims
it
does
not
have
to
follow
the
statutory
criteria
for
delisting
a
source
category
established
in
section
112(
c)(
9)(
b)(
ii).
However,
electric
utility
generating
units
were
properly
listed
as
source
category.
EPA
is
required
to
delist
them
in
accordance
with
the
CAA,
and
may
not
rely
on
inapplicable
and
distinguishable
examples
of
past
delistings
to
support
bypassing
its
clear
statutory
mandate.
EPA's
initial
listing
of
electrical
generating
units
as
a
source
category
was
the
result
of
extensive
scientific
study.
EPA
cannot
delist
EGU
as
a
source
category
except
pursuant
to
section
112(
c)(
9)(
B)(
ii).
EPA
cannot
meet
the
delisting
criteria
for
EGU.
This
is
confirmed
by
EPA's
Industrial
Boiler
rulemaking
(
February
26,
2004).
section
112.
EPA
must
regulate
under
the
Section
112
framework.

°
Commenter
OAR­
2002­
0056­
2920
stated
that
even
if
the
legislative
history
cited
by
EPA
in
support
of
its
proposal
to
regulate
under
CAA
section
111
were
relevant,
it
does
not
support
rescinding
the
regulatory
finding.
Based
on
EPA's
construction
of
CAA
section
111(
d),
commenter
OAR­
2002­
0056­
2823
states
that
the
actual
listing
under
section
112
©
)
precludes
EPA
from
requiring
state
regulation
of
the
source
category
under
section
111(
d).
EPA's
determination
that
it
can
regulate
under
section
111(
d)
because
it
erred
in
the
source
category
listing
under
CAA
section
112
©
)
is
transparent
and
has
no
foundation
in
statutory
language
or
legislative
intent.

°
According
to
Commenter
2173,
EPA
did
not
and
clearly
can
not
meet
the
statutory
requirements
to
delete
utility
units
from
the
list
of
source
categories
under
section
112
©
)
because
(
as
EPA
states
in
the
preamble)
utility
pose
a
threat
to
public
health
and
the
environment
and
EPA's
attempts
to
sidestep
the
source
category
delisting
procedure
lacks
merit.
EPA's
claim
that
its
original
decisions
to
list
utility
units
was
improper
because
of
its
asserted
authority
to
regulate
them
under
section
111
fails
because:
(
1)
EPA's
assertion
that
MACT
regulation
is
not
required
if
there
is
other
CAA
authority
to
regulate
mercury
is
based
on
a
mis­
reading
and
misapplication
of
section
112(
n)(
1)(
A);
(
2)
EPA
has
not
and
cannot
demonstrate
that
the
proposed
section
111
regulations
will
adequately
address
mercury
health
hazards;
and
(
3)
EPA's
attempts
to
harmonize
the
1990
House
and
Senate
­
30­
amendments
to
the
CAA
to
allow
regulation
of
mercury
emissions
from
utility
units
under
section
112(
d)
lacks
merit
(
once
a
pollutant
such
as
mercury
is
listed
as
a
HAP
under
section
112(
b),
section
111(
d)
prohibits
EPA
from
establishing
emission
standards
under
section
111
for
any
such
source
category).
In
addition,
the
NRDC
settlement
requires
EPA
to
regulate
utility
units
under
section
112
and
the
federal
trust
responsibility
requires
EPA
to
meet
a
protective
MACT
standard
under
section
112.
"
S
°
Commenter
2575
contends
that
EPA's
attempt
to
rescind
the
December
2000
regulatory
finding
is
unwarranted
and
illegal.
EPA's
proposed
delisting
violates
section
112
©
)
(
9).
EPA
seeks
to
rescind
the
finding
and
remove
utility
units
from
the
112
©
)
list
stating
that
nothing
prevents
them
from
revisiting
the
finding,
particularly
where
the
basis
for
the
determination
involved
the
scope
of
existing
statutory
provisions
and
those
provisions
have
not
changed
since
1990.
While
EPA
can
"
revisit"
the
finding,
EPA
cannot
alter
it
by
deleting
a
HAP
source
from
the
112
©
)
list
without
meeting
the
delisting
requirements
in
112
©
)
(
9).
Nowhere
does
EPA
make
the
necessary
determination
that
(
1)
mercury
emissions
will
not
exceed
a
level
which
is
adequate
to
protect
public
health
with
an
ample
margin
of
safety
and
(
2)
no
adverse
environmental
effects
will
result
from
the
emissions.
EPA
says
it
can
delist
a
source
category
without
following
the
criteria
because
it
has
done
so
on
several
occasions
in
the
past.
Thankfully,
the
argument
that
a
since
person
has
violated
the
law
in
the
past
with
impunity
,
he
is
allowed
to
continue
doing
so,
is
not
recognized
in
American
law.
Further,
when
EPA
said
it
previously
ignored
the
delisting
requirements,
the
delisting
were
because
subsequent
information
showed
the
sources
were
not
major
sources
of
HAP.
This
is
not
the
case
for
utility
units.
Congress
included
mercury
of
the
section
112(
b)
list
of
HAP
and
required
regulation
of
utility
units
if
the
public
health
study
found
that
impacts
were
significant
enough
to
warrant
regulation
under
section
112.
Nowhere
does
EPA
suggest
that
mercury
from
utility
units
does
not
create
a
public
health
or
environmental
hazard.
EPA
cannot
delist
utility
units
under
the
plain
language
of
section
112
©
)
(
1),
which
requires
EPA
to
list
all
major
sources
of
HAP
listed
to
pursuant
to
section
112(
b).
Mercury
compounds
were
included
on
the
section
112(
b)
list
with
the
original
list
of
HAP.
Absent
a
finding
that
utility
units
are
not
major
sources
of
mercury
emissions,
EPA
must
include
these
sources
on
the
112
©
)
list.

°
According
to
Commenter
2920,
EPA's
proposal
to
remove
power
plants
from
the
section
112
©
)
list
of
source
categories
is
unlawful,
arbitrary,
and
capricious.
EPA
has
not
made
the
statutory
determinations
required
by
section
112
©
)
(
9)
to
delist
a
source
category.
That
EPA
has
previously
delisted
categories
without
complying
with
section
112
©
)
(
9)
does
not
make
it
any
less
unlawful
and
the
circumstances
for
these
previous
delistings
were
very
different.
Here,
EPA
wants
to
undo
a
previous
determination
that
section
112
regulation
of
power
plants
was
necessary
and
appropriate.
It
is
precisely
that
type
of
attempt
at
deregulation
that
the
provisions
of
section
112
©
)
(
9)
were
enacted
to
prevent.
Once
a
category
has
been
placed
on
the
112
©
)
list,
it
cannot
be
removed
without
demonstrating
that
the
risks
from
the
category
fall
below
the
specific
risk
level
cited
in
section
112(
c)(
9)(
B).
­
31­
°
Several
commenters
(
OAR­
2002­
0056­
2519,
­
2660,
­
3449,
­
3459)
stated
that
EPA's
regulatory
determination
was
a
singular
event
with
legal
consequences
that
can
not
be
unmade,
particularly
where
no
new
factual
evidence
supports
that
action.
EPA
must
abide
by
the
consequences
or
use
the
statutorily
prescribed
route
­
section
112
©
)
(
9)
­
to
avoid
MACT
requirements.
And,
EPA
cannot
reverse
the
listing
because
the
plain
language
of
the
CAA
requires
that
section
112
contain
all
major
sources
of
HAP.

°
Commenter
2575
explained
that
while
mercury
was
included
on
the
original
HAP
list
under
section
112(
b),
Congress
allowed
utility
units
to
delay
rules
under
section
112(
n)(
1)
pending
a
study
of
the
adverse
health
effects.
Section
112(
n)(
1)(
A)
requires
EPA
to
regulate
utility
units
under
section
112
if
the
Administrator
finds
such
regulation
is
appropriate
and
necessary
and
after
considering
the
results
of
the
study.
The
conference
committee
for
the
1990
amendments
added
this
provision
because
of
their
concern
about
the
cost
of
immediate
regulation.
Based
on
the
health
effects
study,
EPA
found
it
was
appropriate
and
necessary;
to
regulate
HAP
emissions
from
utility
units
under
section
112.
The
December
2000
finding
brought
mercury
emissions
fully
under
the
regulatory
purview
of
section
112
MACT
standards.
Utility
units
are
on
the
section
112
©
)
major
source
list,
and
EPA
must
establish
emission
standards
for
mercury
emissions
under
section
112(
d).

In
contrast,
many
industry
commenters
contended
that
EPA
was
correct
to
revise
the
determination.

°
Commenter
2948
states
that
nothing
in
EPA's
actions
or
public
statements
provided
notice
to
anyone
that
EPA
would
list
coal­
and
oil­
fired
electric
utility
steam
generating
units
under
§
112
©
)
.
According
to
Commenter
3516,
EPA's
December
2000
listing
decision
was
never
justified
based
on
the
law
or
the
facts.
EPA
never
sought
public
input
for
this
list,
meaning
that
EPA
never
explained
or
defended
its
actions.
In
addition,
nothing
in
the
Agency's
record
justifies
a
conclusion
in
favor
of
EPA's
decision
to
list
coal­
and
oil­
fired
electric
utility
steam
generating
units
under
§
l12
©
)
.
Although
EPA's
Utility
RTC
did
state
that
mercury
was
the
hazardous
pollutant
of
"
greatest
concern,"
it
also
expressly
declined
to
include
a
regulatory
determination
that
mercury
emissions
from
coal­
fired
power
plants
presented
any
concerns
for
public
health,
delaying
any
conclusion
on
that
issue
to
an
some
undefined
future
date.

°
Two
commenters
(
OAR­
2002­
0056­
2248,
­
2833)
believe
the
regulatory
finding
is
not
final
since
EPA
never
subjected
its
finding
to
the
minimum
appropriate
process
under
the
Administrative
Procedure
Act.
In
particular,
although
EPA
allowed
for
some
public
involvement
while
collecting
the
data
that
underlies
the
1997
Hg
report
and
1998
Hg
study,
the
Agency
did
not
allow
for
public
review
or
comment
of
its
final
December
14,
2000,
finding.
This
is
an
essential
element
of
the
regulatory
process
and
it
is
still
well
within
the
discretion
of
EPA
to
modify,
amend,
revise,
or
retract
its
December
14,
2000,
decision.
Since
that
decision
is
still
subject
to
court
review
and
is
a
necessary
prerequisite
to
EPA's
­
32­
regulation
of
Hg,
the
Agency
should
review
and
consider
the
comments
it
receives
on
both
the
December
14,
2000
decision
to
regulate
Hg
emissions
as
well
as
the
proposed
rule.

°
According
to
commenter
OAR­
2002­
0056­
2867,
the
revision
is
not
only
justified
but
also
required
by
new
information
and
developments
that
post­
date
the
original
determination.

°
Two
commenters
(
OAR­
2002­
0056­
2186,
­
2867)
indicated
that
EPA's
regulatory
finding
in
2000
is
not
a
final
regulatory
action.
A
Federal
court
found
that
the
EPA
finding
is
not
ripe
for
review
until
after
it
promulgates
regulations
(
UARG.
v
EPA,
U.
S.
App
LEXIS
18436,
D.
C.
Cir.
2001).
Therefore,
whether
it
is
appropriate
and
necessary
to
regulate
under
section
112(
d)
or
otherwise
is
an
open
question.

°
Commenter
2835
stated
that
EPA
has
the
legal
authority
to
revise
its
December
20,
2000
finding
that
regulation
under
section
112
is
"
appropriate
and
necessary."
EPA
may
promulgate
MACT
standards
for
EGUs
under
section
112(
d)
only
if
such
regulation
is
determined
to
be
"
appropriate
and
necessary"
under
CAA
section
112(
n)(
1)(
A).
Initially,
EPA
made
such
a
determination
in
the
Regulatory
Finding
issued
on
December
20,
2000.
It
is
clear
that
EPA's
Regulatory
Finding
was
predicated
on
the
conclusion
that
no
other
section
of
the
CAA
would
adequately
address
the
public
health
risks
posed
by
mercury
emissions
from
coal­
fired
EGUs
and
nickel
emissions
from
oil­
fired
EGUs.
The
proposed
mercury
rule,
however,
signals
EPA's
intent
to
change
its
direction
on
the
best
way
to
regulate
power
plants.
Specifically,
EPA
states
that,
upon
further
analysis,
its
initial
December
2000
determination
"
lacks
foundation"
given
that
another
air
regulatory
program
 
authorized
under
section
111
 
"
would
adequately
address"
mercury
and
nickel
emissions
from
this
source
category.
This
change
in
direction
is
well
within
EPA's
authority
for
the
following
reasons.
First,
EPA
has
strong
legal
grounds
to
conclude
that
its
December
2000
Finding
was
not
a
final
agency
action
and
but
rather
only
a
preliminary
step
in
EPA's
extended
deliberations
as
to
whether
to
list
coal­
fired
EGUs
under
Section
112
and
develop
MACT
emissions
standards
for
this
source
category
under
that
section.
In
such
cases,
EPA's
decision
to
change
direction
and
adopt
a
cap­
and­
trade
program
in
lieu
of
MACT
standards
is
ordinarily
subject
to
a
highly
deferential
standard
of
review.
Specifically,
EPA
is
"
entitled
to
a
presumption
of
regularity,"
and
the
court
cannot
"
substitute
its
judgment
for
that
of
the
agency."
However,
even
assuming
that
the
initial
Regulatory
Finding
was
a
final
agency
action,
the
rationale
proffered
in
the
preamble
is
most
likely
sufficient
to
meet
the
"
reasoned
analysis"
test.
It
is
well
established
that
an
agency
can
change
its
view
of
what
is
in
the
public
interest,
even
if
circumstances
do
not
change;
however,
a
reasoned
analysis
must
be
supplied.

In
contrast,
one
commenter
(
OAR­
2002­
0056­
3537)
stated
that
the
CAA
did
not
require
that
EPA
list
utility
units
under
section
112
©
)
.
The
commenter
noted
that
section
112(
n)(
1)(
A)
provided
EPA
broad
discretion
to
address
any
specific
public
health
risks
identified
as
a
result
of
its
Utility
Report
to
Congress.
It
vested
in
EPA
the
ability
to
develop
alternate
control
strategies
under
the
CAA,
other
than
a
mere
listing
of
utility
units
under
section
112
©
)
and
establishment
of
MACT
standards
under
section
112(
d).
The
commenter
submitted
that
such
interpretation
was
supported
­
33­
by
a
plain
reading
of
the
statute
(
i.
e.,
section
112(
n)(
1)(
A))
and
the
legislative
history
leading
up
to
the
enactment
of
section
112(
n)(
1)(
A).
The
commenter
concluded
that
EPA's
decision
to
list
utility
units
rested
on
an
incorrect
reading
of
section
112(
n)(
1)(
A)
and
must,
therefore,
be
reconsidered
and
reversed
during
this
rulemaking.

Response:

EPA
disagrees
with
the
comments
that
contend
that
the
Agency
cannot
remove
utility
units
from
the
section
112
©
list
without
meeting
the
terms
of
section
112(
c)(
9).
The
reasons
for
the
Agency's
position
are
described
in
the
preamble
to
today's
action.

4.0
OTHER
LEGAL
CHALLENGES
Comment:

Two
commenters
do
not
support
the
regulation
of
Hg
emissions
because
the
2000
finding
was
not
subject
to
appropriate
public
notice
and
comment
under
the
Administrative
Procedure
Act
(
OAR­
2002­
0056­
3530,
­
3537).

Response:

EPA
did
not
provide
notice
and
an
opportunity
to
comment
on
the
December
2000
regulatory
finding
because
it
concluded
that
this
was
not
necessary
since
it
had
previously
held
public
meetings
soliciting
oral
and
written
comments
regarding
the
regulatory
finding
and
had
provided
numerous
opportunities
to
comment
on
matters
relating
to
the
Utility
Study
and
the
regulatory
finding.
The
EPA
also
believed
that
notice
and
an
opportunity
to
comment
was
not
necessary
because
ample
opportunity
to
comment
on
the
regulatory
determination
would
be
available
in
the
context
of
the
development
and
adoption
of
appropriate
regulations.
Regardless
of
whether
notice­
and­
comment
requirements
applied
to
EPA's
December
2000
determination,
by
virtue
of
the
January
2004
proposed
rule,
EPA
provided
a
sufficient
opportunity
for
notice
and
comment
on
whether
Utility
Units
should
be
regulated
under
section
112
on
the
basis
utility
HAP
emissions.

Comment:

One
commenter
(
OAR­
2002­
0056­
2887)
believed
that
the
risk
assessment
conducted
for
the
Utility
RtC
was
incomplete
and
inadequate.
The
commenter
contended
that
EPA
did
not
address
1995
external
peer
review
comments,
including
a
specific
request
that
analyses
of
other
HAP
be
conducted.
Therefore,
the
record
did
not
support
EPA's
conclusion
that
other
HAP
examined
in
the
Utility
RtC
did
not
appear
to
be
a
concern
for
public
health.
The
commenter
contended
that
EPA
­
34­
could
not
make
the
determination
that
other
HAP
should
be
excluded
from
regulation
without
completing
an
adequate
risk
assessment
of
HAP
emitted
from
electric
utility
units.
The
commenter
believed
EPA
also
was
obligated
to
consider
the
advancements
made
in
risk
assessments
since
1993­
1994
to
ensure
that
the
regulatory
decision
was
adequately
protective
of
public
health
and
scientifically
defensible.
This
included
an
assessment
of
more
recent
information
on
the
HAP
health
effects,
cumulative
risk
associated
with
all
HAP
emissions,
and
inclusion
of
potentially
sensitive
subpopulations
in
the
assessment.
The
commenter
stated
EPA
also
should
provide
a
summary
of
its
response
to
external
peer
review
comments.
EPA
also
needed
to
correct
the
summary
of
the
Hg
health
effects
in
the
proposal
preamble
that
downplays
the
findings
of
adverse
health
effects.
The
commenter
also
believed
it
was
important
that
EPA
include
recent
studies
that
confirm
risks
to
the
developing
brain
and
cardiovascular
system
from
MeHg
exposure,
and
stated
that
recent
studies
also
linked
the
neurological
changes
to
decreased
nervous
system
control
of
heart
function.

Response:

The
EPA
believes
that
risk
assessment
conducted
for
the
Utility
RtC
was
both
complete
and
adequate
and
that
the
HAP
that
it
was
necessary
to
consider
were
in
fact
considered.
The
HAP
that
were
identified
for
further
study
in
the
Utility
RtC
were
so
identified
on
the
basis
of
a
screening
analysis.
That
screening
analysis
indicated
that
only
14
of
the
67
HAP
identified
as
potentially
being
emitted
by
Utility
Units
were
identified
as
priority
for
further
evaluation.
Those
14
HAP
were
further
evaluated.
As
discussed
in
detail
in
the
recently
signed
rule
titled
Revision
of
December
2000
Regulatory
Finding
on
the
Emissions
of
Hazardous
Air
Pollutants
from
Electric
Utility
Steam
Generating
Units
and
the
Removal
of
Coal­
and
Oil­
fired
Electric
Utility
Steam
Generating
Units
from
the
Section
112(
c)
list,
EPA
believes
that
the
record
did
support
its
conclusion
that
HAP,
other
than
mercury,
examined
in
the
Utility
RtC
did
not
appear
to
be
a
concern
for
public
health.
As
to
the
issue
of
more
recently
available
information,
EPA
is
constantly
faced
with
the
dilemma
of
either
having
to
draw
the
line
regarding
the
information
it
is
going
to
consider
in
the
first
instance
in
making
key
decisions
or
never
being
able
to
make
those
decisions
since
new
information
is
generally
generated
at
rapid
pace.
As
a
result,
EPA
often
must
make
decisions
based
on
the
information
before
it
at
a
given
point
in
time
in
taking
a
final
action
and
then
considers
subsequently
available
information
in
deciding
whether
to
later
revisit
that
final
action.
This
is
one
of
those
situations.

4.3
Effect
on
Utility
Units
already
permitted
pursuant
to
section
112(
g).

Comment:

One
commenter
notes
that
some
utility
units
that
have
been
permitted
since
December
2000
have
undergone
a
112(
g)
case
by
case
MACT
determination.
Guidance
is
requested
as
to
how
the
revision
of
the
December
2000
finding
affects
these
determinations
that
were
made
based
on
the
December
2000
finding.
Guidance
is
also
needed
as
to
application
of
EPA's
once
in
always
in
policy.
(
OAR­
2002­
0056­
2430).
­
35­
Response:

EPA
is
not
addressing
today
the
issues
raised
by
these
comments.
The
Agency
will
continue
to
consider
the
commenter's
suggestion
for
guidance
on
the
applicability
of
section
112(
g).
