Technical
Support
Document
on
Emissions
Inventory
Reporting
Requirements
for
the
Proposed
Clean
Air
Interstate
Rule
U.
S.
Environmental
Protection
Agency
Office
of
Air
Quality
Planning
and
Standards
Emissions
Analysis
and
Monitoring
Division
Research
Triangle
Park,
NC
27711
May
2004
2
Purpose
This
document
provides
further
information
describing
the
proposed
changes
to
40
CFR
51
Subpart
A
and
section
51.
122
and
the
proposed
new
section
51.125,
concerning
requirements
for
emission
reporting
by
States
to
EPA.
The
purpose
is
to
facilitate
public
understanding
of
the
reasons
for
the
proposed
changes,
in
order
to
allow
public
comment
on
the
merits
of
the
changes.
The
information
provided
here
supplements
with
more
detail
the
summary
of
the
proposed
changes
contained
in
section
III.
B
of
the
preamble
to
the
Supplemental
Notice
of
Proposed
Rulemaking
for
the
Clean
Air
Interstate
Rule.

The
information
is
presented
in
two
tables.
Table
1
summarizes
in
a
broad
manner
the
reporting
requirements
that
would
apply
to
States
in
particular
situations.
Table
2
lists
individual
proposed
changes
to
the
rule
text
and
the
purpose
of
each.

Questions
on
the
proposed
requirements
may
be
addressed
to
William
Kuykendal
at
kuykendal.
bill@
epa.
gov
or
(
919)
541­
5372.
3
Table
1
Summary
of
Reporting
Requirements
and
Rationales
General
Content
of
Required
Report
States
Affected
Sources
Affected
Every
year
Requirements
(
presumed
met
by
three­
year
requirements
when
years
coincide)
Three­
year
Requirements
(
2005,
2008,
etc.
)
Rationale
Annual
emissons
from
all
sources
in
all
states
every
third
year
All
All
sources
(
New
definition
of
point
sources
is
proposed
to
take
effect
in
2008,
but
asking
for
comment
on
2005)
Submit
data
elements
in
Tables
2a,
2b,
and
2c
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

All
pollutants
Annual
emissions
For
all
States,
this
is
requirement
of
existing
Subpart
A
Annual
emissions
from
very
large
point
sources
every
year
All
Type
A
sources
(
see
criteria
in
Table
1
of
appendix
to
51
Subpart
A)
Submit
data
elements
in
Table
2a
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

All
pollutants
Annual
emissions
Starts
in
2003
(
due
June
2005)
For
all
States,
this
is
requirement
of
existing
Subpart
A
General
Content
of
Required
Report
States
Affected
Sources
Affected
Every
year
Requirements
(
presumed
met
by
three­
year
requirements
when
years
coincide)
Three­
year
Requirements
(
2005,
2008,
etc.
)
Rationale
4
NOx
emissions
in
states
contributing
significantly
to
ozone
nonattainment
in
another
state,

all
sources,

every
three
years
AL,
CT,
DE,

DC,
IL,
IN,

KY,
MA,
MD,

MI,
MS,
NC,

NJ,
NY,
OH,

PA,
RI,
SC,

TN,
VA,
WV
All
sources
Submit
data
elements
in
Tables
2a,
2b,
and
2c
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

Ozone
season
NOx
Summer
day
NOx
Starts
with
2005
ozone
season
Current
NOx
SIP
Call
requirement
VOC
emissions
in
states
contributing
significantly
to
ozone
nonattainment
in
another
state,

all
sources,

every
three
years
AL,
CT,
DE,

DC,
IL,
IN,

KY,
MA,
MD,

MI,
MS,
NC,

NJ,
NY,
OH,

PA,
RI,
SC,

TN,
VA,
WV
All
Submit
data
elements
in
Tables
2a,
2b,
and
2c
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

Summer
day
VOC
Asking
for
comment
on
CO
Submission
of
daily
VOC
is
a
requirement
of
the
existing
Subpart
A.

EPA
is
proposing
to
keep
it
only
for
areas
with
ozone
concern.
These
states
contribute
to
nonattainment
in
other
states.
General
Content
of
Required
Report
States
Affected
Sources
Affected
Every
year
Requirements
(
presumed
met
by
three­
year
requirements
when
years
coincide)
Three­
year
Requirements
(
2005,
2008,
etc.
)
Rationale
5
NOx
emissions
in
states
contributing
significantly
to
ozone
nonattainment
in
another
state,

from
sources
controlled
to
meet
NOx
SIP
call
requirements,

every
year
AL,
CT,
DE,

DC,
IL,
IN,

KY,
MA,
MD,

MI,
MS,
NC,

NJ,
NY,
OH,

PA,
RI,
SC,

TN,
VA,
WV
However,
all
have
joined
the
EPA
trading
program.
Only
sources
subject
to
control
to
get
required
Nox
reductions,
unless
reporting
to
EPA
through
a
trading
program
Submit
applicable
data
elements
in
Tables
2a,
2b,
and
2c
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

Ozone
season
NOx
Summer
day
NOx
Starts
2003
Current
NOx
SIP
call
requirement
Same
as
above
GA,
MO
Same
requirements
as
for
the
above
3
lines,
except
that
no
reporting
is
required
until
the
2006
inventory
year.
These
States
have
been
added
to
the
NOx
SIP
call.
General
Content
of
Required
Report
States
Affected
Sources
Affected
Every
year
Requirements
(
presumed
met
by
three­
year
requirements
when
years
coincide)
Three­
year
Requirements
(
2005,
2008,
etc.
)
Rationale
6
Ozone­
related
emissions
on
a
typical
summer
day,
in
states
with
ozone
nonattainment
areas,
all
sources,
every
three
years
States
containing
an
ozone
nonattainment
designated
by
EPA
rule
on
April
15,
2004.
All
sources
Submit
data
elements
in
Tables
2a,
2b,
and
2c
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

Summer
day
NOx
and
VOC,
Taking
comment
on
CO
Starts
2005
A
requirement
of
the
existing
Subpart
A
EPA
is
proposing
to
keep
it
only
for
areas
with
ozone
concern.
These
states
have
8­
hour
ozone
nonattainment
areas.

Annual
and
ozone­
season
NOx
emissions
in
states
included
in
the
CAIR
due
to
contribution
to
ozone
nonattainment
in
another
state,

all
sources
every
three
years
AL,
AR,
CT,

DC,
DE,
GA,

IL,
IN,
MD,

MA,
MI,
MS,

MO,
NJ,
NY,

NC,
OH,
PA,

SC,
TN,
VA,

WV,
WI
All
sources
Submit
data
elements
in
Tables
2a,
2b,
and
2c
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

Annual
NOx
Ozone
season
NOx
Starts
2008
These
States
are
subject
to
CAIR
for
ozone
reasons.

Annual
NOx
allows
tracking
of
budget
compliance
for
regulatory
purposes;

ozone
season
allows
tracking
for
air
quality
effect.
General
Content
of
Required
Report
States
Affected
Sources
Affected
Every
year
Requirements
(
presumed
met
by
three­
year
requirements
when
years
coincide)
Three­
year
Requirements
(
2005,
2008,
etc.
)
Rationale
7
Annual
and
ozone­
season
NOx
emissions
in
states
included
in
the
CAIR
due
to
contribution
to
ozone
nonattainment
in
another
state,

controlled
sources
only,

every
three
years
AL,
AR,
CT,

DC,
DE,
GA,

IL,
IN,
MD,

MA,
MI,
MS,

MO,
NJ,
NY,

NC,
OH,
PA,

SC,
TN,
VA,

WV,
WI
Sources
subject
to
control
to
get
required
CAIRrequired
reductions,

unless
reporting
to
EPA
through
a
trading
program
Submit
applicable
data
elements
in
Tables
2a,
2b,
and
2c
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

Annual
NOx
Ozone
season
NOx
Starts
2009
Would
extend
every­
year
reporting
requirements
of
the
NOx
SIP
call
to
new
states
found
to
contribute
significantly
to
ozone
nonattainment
in
another
state.

These
States
are
subject
to
CAIR
for
ozone
reasons.

Annual
NOx
allows
tracking
of
budget
compliance
for
regulatory
purposes;

ozone
season
allows
tracking
for
air
quality
effect.
General
Content
of
Required
Report
States
Affected
Sources
Affected
Every
year
Requirements
(
presumed
met
by
three­
year
requirements
when
years
coincide)
Three­
year
Requirements
(
2005,
2008,
etc.
)
Rationale
8
Annual
and
NOx
and
SO2
emissions
in
states
included
in
the
CAIR
due
to
contribution
to
PM2.5
nonattainment
in
another
state,

all
sources
every
three
years
AL,
AR,
DC,

DE,
FL,
GA,

IL,
IN,
IA,
KS,

KY,
LA,
MA,

MD,
MI,
MN,

MS,
MO,
NJ,

NY,
NC,
OH,

PA,
SC,
TN,

TX,
VA,
WV,

WI
All
sources
Submit
data
elements
in
Tables
2a,
2b,
and
2c
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

Annual
NOx
and
SO2
Starts
2008
These
States
area
subject
to
CAIR
for
reasons
of
PM2.5
Reporting
of
annual
SO2
and
NOx
from
all
sources
at
threeyear
interval
allows
tracking
of
regulatory
compliance
and
annual
PM2.5
air
quality
factors.
General
Content
of
Required
Report
States
Affected
Sources
Affected
Every
year
Requirements
(
presumed
met
by
three­
year
requirements
when
years
coincide)
Three­
year
Requirements
(
2005,
2008,
etc.
)
Rationale
9
Annual
Nox
and
SO2
emissions
in
states
included
in
the
CAIR
due
to
contribution
to
ozone
nonattainment
in
another
state,

controlled
sources
only,

every
three
years
AL,
AR,
DC,

DE,
FL,
GA,

IL,
IN,
IA,
KS,

KY,
LA,
MA,

MD,
MI,
MN,

MS,
MO,
NJ,

NY,
NC,
OH,

PA,
SC,
TN,

TX,
VA,
WV,

WI
Sources
subject
to
control
to
get
required
reductions,

unless
reporting
to
EPA
through
a
trading
program
Submit
applicable
data
elements
in
Tables
2a,
2b,
and
2c
of
the
Appendix
to
40
CFR
51
Subpart
A
for:

Annual
SO2
Annual
NOx
Starts
2009
These
States
area
subject
to
CAIR
for
reasons
of
PM2.5
Reporting
of
annual
SO2
and
NOx
from
all
controlled
sources
every
year
allows
tracking
of
regulatory
compliance
and
annual
PM2.5
air
quality
factors.
10
Table
2
Proposed
Changes
in
Emissions
Reporting
Requirements
in
40
CFR
Part
51
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
Table
of
contents
for
51
Subpart
A
Some
section
headings
are
revised.
Changed
"
Glossary"
to
"
Definitions".
Clarity.
Definitions
in
Subpart
A
now
also
serve
51.122
where
they
previously
were
called
definitions
rather
than
glossary.

51.1
Add
phrase
indicating
that
States
are
not
required
to
submit
emission
inventory
information
for
sources
on
tribal
lands
Clarity.
States
do
not
have
regulatory
over
these
sources
and
in
general
do
not
have
direct
access
to
information
on
their
emissions.

51.1
Minor
edits.
Make
more
succinct.

51.10
Add
reference
to
the
Clean
Air
Interstate
Rule.
State
that
requirements
under
that
rule
and
under
the
NOx
SIP
call
are
contained
in
Subpart
A.
Clarity.
The
detailed
list
of
required
data
elements
would
be
removed
from
51.122.
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
11
51.15(
a)
Reorganize
to
state
the
required
pollutants
separately
for
the
different
applicable
emission
reporting
periods.

Limit
pollutants
to
those
relevant
to
the
purpose
of
the
reporting
requirement
for
that
time
period's
emissions.
Existing
51.15(
a)
required
reporting
of
all
pollutants
for
each
of
annual,
ozone
season
day,
and
winter
season
day,

some
which
had
no
relevance.

Revision,
for
example,

removes
requirement
for
reporting
of
SO2
emissions
for
ozone/
summer
season
day.

51.15(
a)
Spell
out
Volatile
Organic
Compounds.

Make
clear
that
the
required
reporting
of
PM10
and
PM2.5
emissions
includes
specific
reporting
of
condensible
and
filterable
particular
matter
where
applicable.
Clarity.
Clarity.
Requirement
is
currently
implied
in
the
definition
of
PM.

51.15(
a)(
7)
Add
statement
that
other
pollutants
may
also
be
reported.
Clarity,
since
some
States
may
find
it
less
work
to
report
all
pollutants
in
their
data
system
rather
than
filter
to
just
those
required
for
the
time
period
at
issue,
and
may
wish
to
provide
emissions
of
hazardous
air
pollutants
voluntarily,
per
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
12
EPA
request.

51.15(
b)
Clarify
that
a
State
is
not
required
to
report
sources
on
tribal
lands.

Change
"
Area"
to
"
Non­
Point"
See
above.

See
footnote
in
section
III.
B
preamble.

51.15(
c)
Add
statement
that
EPA
may
require
information
on
the
method
of
determination
for
data
elements
listed
later
in
Subpart
A.

Add
the
example
of
the
State
contact
person
to
the
existing
statement
that
"
additional
information
not
listed
in
"
Source
of
data"
is
required
by
the
existing
51.122
for
several
listed
data
elements.

However,
EPA's
current
electronic
data
format
does
not
specify
a
means
to
report
this
information.
Rather
than
list
these
as
data
elements
in
the
tables
in
Subpart
A,
this
provision
allows
EPA
to
consider
the
need
for
this
information
each
year
and
to
specify
the
format
for
reporting
it.

To
make
clearer
that
this
statement
is
not
intended
to
allow
EPA
to
make
substantive
additions
to
the
list
Is
it
necessary
to
set
a
deadline
each
year
for
EPA
to
designate
which
data
elements
require
reporting
of
method
of
determination?
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
13
Tables
2a
through
2d
may
be
required."
of
data
elements
through
the
non­
rulemaking
mechanism
of
the
reporting
format.

51.15(
e)
New
paragraph
added,
to
allow
the
option
of
submission
of
emissions
inventory
model
inputs
instead
of
actual
emissions
values.
See
preamble.
A
current
example
would
be
inputs
for
the
new
National
Mobile
Inventory
Model
(
NMIM).

51.20(
a)
and
(
b)
Base
point
source
reporting
on
whether
a
source
is
"
major",

rather
than
on
cutoffs
based
on
actual
emissions
in
the
year
at
issue.
Change
is
mandatory
starting
in
2008.

Remove
requirement
for
reporting
biogenic
emissions.
See
preamble.

See
preamble.
How
else
might
difficulties
caused
by
a
changing
universe
of
reporting­
eligible
sources
from
year­
to­
year
as
under
the
current
rules
be
managed?

How
would
this
actually
affect
the
number
of
sources
reported
as
point
sources,
and
what
effect
would
this
have
on
State
workload?
Does
the
State
currently
have
the
necessary
emissions
data
for
the
additional
sources,
or
would
changes
in
State
rules
and
practices
be
required?
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
14
51.20(
d)
Add
statement
that
reporting
of
non­
point
sources
must
include
wildfires
and
prescribed
fires,
but
is
not
required
to
include
windgenerated
dust.

Add
statement
that
non­
point
Clarify
that
fires
are
potentially
important
emission
sources
and
are
encompassed
under
the
term
"
anthropogenic
stationary
sources"
for
purposes
of
this
Subpart,
due
to
the
interaction
of
prescribed
fires
and
wildfire
prevention.

This
is
not
intended
to
have
any
effect
on
the
meaning
of
provisions
of
other
CFR
sections
that
may
address
fires.

Wind­
generated
dust
is
explicitly
excluded
to
clarify
EPA
intent
and
current
practice.
Note
that
wind
generated
dust
from
roads
and
material
storage
piles
at
major
point
sources
are
required
to
be
reported.
Wind­
generated
dust
from
natural
landscapes
and
from
fields
that
have
been
plowed
but
are
not
yet
covered
by
vegetation
would
be
excluded.

Clarity,
reflects
current
EPA
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
15
sources
must
be
identified
by
source
classification
code.

Add
statement
that
non­
point
source
categories
with
de
minimus
emissions
may
be
excluded.
practice
in
interpreting
this
section.
Practicability
and
efficiency.

51.25
Change
"
an
area's"
to
"
any
area's"
Clarity
51.30
Add
provisions
related
to
NOx
SIP
call
(
previously
contained
only
in
51.122
and
not
in
Subpart
A)
and
provisions
related
to
the
Clean
Air
Interstate
Rule.
Restructure
and
re­
phrase
for
clarity.
Requirements
related
to
the
Clean
Air
Interstate
Rule
are
based
on
the
reason(
s)
each
State
is
affected.
For
example,

States
contributing
significantly
to
ozone
nonattainment
in
another
State
would
be
required
to
report
ozone­
relevant
data
like
States
presently
subject
to
the
NOx
SIP
call,
but
States
contributing
only
to
PM2.5
nonattainment
would
report
only
annual
SO2
and
NOx.
Note
that
under
the
existing
Subpart
A,
all
States
are
required
to
report
all
pollutants
for
winter
and
ozone
season
day.
The
proposed
revision
removes
the
requirement
for
winter
day
reporting
(
for
reasons
stated
in
the
preamble)

and
limits
the
ozone
season
day
(
now
proposed
to
be
termed
summer
season
day)

reporting
only
to
VOC
and
NOx
and
only
to
areas
with
ozone
nonattainment
or
contributing
to
nonattainment
in
another
State.
Should
summer
day
reporting
include
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
16
The
reports
now
required
by
51.122
to
be
submitted
on
December
31
of
the
next
year
will
instead
be
due
June
1
of
the
second
year
following
the
year
being
reported.

The
existing
requirement
of
51.122
for
full
reporting
of
all
sources
for
2007
is
not
retained.
Consolidate
reporting
transactions,
for
efficiency.

See
preamble
for
explanation.
CO,
which
makes
some
contribution
to
ozone
formation?

Instead,
should
all
or
some
of
the
reporting
which
Subpart
A
now
requires
on
June
1
be
moved
forward
to
December
31?
See
discussion
in
preamble.

51.35(
a)(
3)

(
And
deletion
of
current
51.35(
d)
and
renumbering
of
remaining
paragraphs.)
Remove
the
alternative
of
a
State
submitting
one­
third
of
its
three­
year
sources
each
year.
Instead,
State
may
obtain
data
on
one­
third
of
the
sources
each
year
but
must
submit
all
the
data
in
one
transaction.
Efficiency
in
EPA
handling
and
analysis
of
submitted
data,

and
avoiding
errors
related
to
source
identification
and
matching.
To
EPA's
knowledge,
no
State's
current
or
planned
practice
will
be
affected.
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
17
51.40
Add
a
statement
better
indicating
what
specifications/
requirements
can
be
part
of
the
electronic
data
format,
which
EPA
may
change
from
year­
to­
year
without
amendment
to
Subpart
A,
e.
g.,
that
the
electronic
data
format
may
specify
that
more
than
one
data
field
is
required
for
a
single
data
element
listed
in
Tables
2a
through
2d.
Clarity.
Reflects
current
EPA
practice
in
applying
existing
Subpart
A.

Table
1
Simplify
by
removing
classification­
dependent
emissions
cutoffs
for
point
source
reporting,
which
would
instead
be
based
on
status
as
a
"
major"
source.
See
preamble
for
explanation
of
the
purpose
of
basing
point
sources
on
"
major"
source
status.
Requirements
for
reporting
as
Type
A
sources
every
year
are
not
affected.
The
term
"
Type
B"
is
not
longer
necessary
and
is
not
used.

Table
2a
Revised
to
address
all
required
data
elements
for
point
sources
in
consolidated
form.
Details
for
data
elements
being
altered
Separate
State
and
county
FIPS
codes
are
reduced
to
a
single
combined
FIPS
code,

per
current
practice.
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
18
or
otherwise
of
special
interest
are
listed
in
the
next
column.

A
State
would
enter
this
table
once
it
had
determined
which
time
periods
and
pollutants
it
was
required
to
report,
based
on
its
status
under
51.122,

51.123,
51.124,
and
51.125.
Point
ID
code
is
replaced
with
Unit
ID
code,
per
current
practice.

Heat
content
of
fuel
in
the
ozone
season,
if
applicable,
is
added,
since
it
is
a
current
requirement
of
the
NOx
SIP
call.
Activity
data
element
is
generalized
from
"
annual"
and
"
daily"
to
"
for
each
period
reported"
since
this
list
of
data
elements
now
applies
to
annual
reporting,
ozone
season
reporting,
and
summer
day
reporting.

"
Work
weekday"
is
replaced
by
"
summer
daily",
per
reasons
explained
in
the
preamble.
In
some
areas,
the
conditions
of
greatest
concern
may
occur
on
weekend
days.

Futher
explanation
appears
in
the
definition
of
"
summer
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
19
daily."

Add
"
Ozone
season
emissions
(
if
applicable)",
since
this
list
now
must
address
the
requirements
of
the
NOx
SIP
call
and
the
Clean
Air
Interstate
Rule.
(
Previous
Subpart
A
addressed
only
annual
emissions
and
daily
emissions.)
Applicability
of
ozone
season
emissions
reporting
is
given
in
51.30.

Terminology
(
and
later
definitions)
for
X
and
Y
coordinated
are
correct
to
reflect
current
practice
as
to
which
represents
latitude
vs.

longitude.
"
Method
accuracy
descriptions"
are
added
as
a
required
data
element,
and
will
be
further
defined
in
the
electronic
reporting
format.

The
requirement
to
identify
the
SIC/
NAICS
code
is
What
is
the
impact
on
the
State
of
the
requirement
to
provide
method
accuracy
descriptions?
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
20
clarified
to
indicate
that
this
must
be
provided
at
both
the
facility
and
unit
levels.
This
is
a
requirement
of
the
current
reporting
format.

"
Design
capacity"
is
reworded
to
clarify
that
it
can
refer
to
boiler
capacity,
as
in
the
parallel
but
differently­
worded
terminology
of
the
existing
51.122
"
Maximum
nameplate
capacity"
is
reworded
to
include
"
generator",
as
in
the
parallel
but
differently­
worded
terminology
of
the
existing
51.122.

"
Primary
control
efficiency"
is
replaced
with
"
Primary
collection
and
control
efficiency"
(
requiring
2
values).
This
reflects
current
practice
and
reporting
format.

Control
efficience
alone
is
not
Preamble
invites
comment
on
appropriate
data
elements
for
describing
type
and
effectiveness
of
controls
at
sources.
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
21
useful.

"
Secondary
control
efficiency"

is
replaced
with
"
Total
capture
and
control
efficiency."
This
reflects
current
practice
and
reporting
format,
makes
Tables
2a
and
2b
more
consistent,
and
allows
description
of
net
effects
of
primary
and
all
other
control
devices.
Preamble
invites
comment
on
appropriate
data
elements
for
describing
type
and
effectiveness
of
controls
at
sources.

Table
2a
No
change
is
proposed
but
comment
is
requested
regarding
stack
parameters
(
exit
gas
velocity,
exit
gas
flow
rate,
and
stack
diameter)
See
preamble
for
explanation.

Any
one
of
these
can
be
calculated
from
the
other
two.
Which
of
the
three
is
most
often
subject
to
actual
physical
measurement
and
should
be
preferred
for
reporting?

Table
2a
No
change
is
proposed
but
comment
is
requested
regarding
hr/
day
in
operation,

start
time,
day/
wk
in
operation,
and
wk/
yr
in
operation.
See
preamble.
These
longstanding
data
elements
are
useful
for
determining
typical
hourly
and
daily
emissions
while
a
source
is
in
operation,

if
annual
emissions
of
an
intermitent
source
are
known.

This
is
most
relevant
to
estimation
of
relatively
near­
Are
these
data
elements
relevant
to
the
purposes
of
the
emission
reporting
requirements?
Should
they
be
retained?
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
22
by
short
term
air
quality
impacts,
as
required
for
new
source
review,
for
example.

Table
2c
No
change
is
proposed,
but
comment
is
requested
regarding
current
requirement
of
Subpart
A
for
reporting
of
the
4
seasonal
throughputs
(
VMT)
for
highway
mobile
sources.
Current
data
reporting
format
does
not
support
these
data
elments.
Moreover,
knowing
the
four
seasonal
throughput
values
does
not
allow
annual
emissions
to
be
allocated
to
seasons
correctly
since
emission
factors
vary
by
season.
Therefore,
usefulness
of
these
data
is
an
issue.
If
highway
mobile
source
emissions
are
reported
by
month
or
if
inputs
to
the
relevant
emissions
inventory
model
are
provided,
these
datda
elements
would
be
redundant.
Are
these
data
elements
relevant
to
the
purposes
of
the
emission
reporting
requirements?
Should
they
be
retained?
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
23
Table
2b
Retitled
for
clarity.

Changes
in
data
elements
parallel
those
described
above
for
Table
2a,
but
limited
to
data
elements
relevant
to
nonpoint
sources.

Table
2c
Retitled
for
clarity.

Changes
in
data
elements
parallel
those
described
above
for
Table
2a,
but
limited
to
data
elements
relevant
to
mobile
sources.
Note
that
the
"
activity"
data
element
for
mobile
sources
is
the
same
as
for
the
current
Subpart
A,
and
differs
from
that
in
the
current
51.122.
The
latter
is
obsolete
and
does
not
represent
current
practice
with
available
emission
estimation
methods
and
models.

Definitions
Previous
titled
"
Glossary".

Definitions
are
corrected,

consolidated,
and
harmonized
with
their
usage
in
the
preceding
sections
and
tables.
Activity
throughput
and
fuel
heat
content
are
generalized
to
the
period
of
interest,
rather
than
being
separately
defined
for
annual
and
daily.

Design
capacity
is
made
more
relevant
to
the
case
of
a
boiler,

using
language
presently
in
51.122.
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
24
Facility
ID
codes
­
clarify
that
one
facility
may
have
several
codes
assigned
by
different
authorities
and
all
must
be
reported
if
specified
by
the
applicable
data
reporting
format.
Inventory
type
is
redefined
to
match
current
practice,
in
which
a
single
data
file
covers
multiple
time
periods,
and
therefore
"
type"
is
not
used
to
distinguish
time
period.

Maximum
nameplate
capacity
changed
to
maximum
generator
nameplate
capacity,

as
appears
now
in
51.122.

Definition
added
for
nitrogen
oxides.

Area
source
replaced
by
nonpoint
source.

Definition
added
for
ozone
Presently,
Subpart
A
is
ambiguous
about
whether
States
must
report
ID
codes
they
have
not
themselves
assigned
to
a
source.
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
25
season,
copied
from
existing
51.122.
Definitions
of
PM
(
particulate
matter)
are
clarified
to
more
explicitly
address
PM10,

PM2.5,
condensible
PM,
and
filterable
PM.

Point
ID
code
replaced
by
Unit
ID
code.

Point
source
definition
revised
to
hinge
on
status
as
"
major".

Pollutant
code
definition
updated
to
reflect
current
practice.

Primary
control
efficiency
is
replaced
with
Primary
capture
and
control
efficiency.

Roadway
class
definition
corrected
to
reflect
current
practice.
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
26
Secondary
control
efficiency
is
deleted,
since
no
longer
in
Table
2a.

Start
time
definition
revised
to
match
current
practice.

Summer
work
weekday
emissions
changed
to
summer
daily
emissions,
with
longer
discussion.

Definition
added
for
total
capture
and
control
efficiency.

Type
B
source
definition
removed,
no
longer
needed.

VMT
by
roadway
class
replaced
by
VMT
by
SCC,

reflecting
current
practice
to
provide
information
by
vehicle
type
as
well
as
roadway
type.

X
and
Y
coordinate
definitions
corrected.
X
represents
longitude,
i.
e.,
east­
west
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
27
coordinate.

51.122
in
general
Shorten
by
moving
detailed
lists
of
required
date
elements
and
definitions
to
Subpart
A.

However,
the
following
data
elments
now
listed
in
51.122
are
not
being
added
to
the
data
element
tables
in
Subpart
A.

Instead,
this
information
will
be
addressed
in
the
year­

toyear
specification
of
the
supporting
data
requirements;

see
proposed
revision
to
section
51.15(
c).

Point
Sources
­
Source
of
fuel
heat
content
data
­
Source
of
activity/
throughput
data
­
Source
of
emission
factor
Non­
point
(
area)
Sources
­
Source
of
emission
factor
­
Source
of
activity/
throughput
data
Lists
are
moved
to
consolidate
requirements
in
one
location.
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
28
­
Source
of
emissions
data
Mobile
Sources
­
Source
of
emission
factor
­
Source
of
activity
data
In
addition,
the
current
51.122
requires
the
data
element
"
Area
designation."
EPA
proposes
not
to
require
this
in
the
consolidated
list
of
data
elements
in
the
new
Subpart
A
Table
2a
.
Designations
change
from
time
to
time,
and
are
available
from
other
compilations.

51.122(
b)(
1)
The
term
"
annual
reporting"
is
replaced
with
"
every
year
reporting"
To
avoid
possible
confusion
with
reporting
of
emissions
for
an
annual
(
12­
month)
period.

51.122(
b)(
2)
The
term
"
triennial
reporting"

is
replaced
with
"
three­
year
cycle
reporting"
Clarity
and
consistency
with
terminology
of
51
Subpart
A.
Section
Amended
or
Added
Proposed
Changes
or
Addition
Reasons
for
Proposed
Changes
Request
for
Comment
and
other
Special
Notes
29
Previous
51.122(
b)(
3)
Deleted,
subsequent
paragraphs
renumbered
Remove
requirement
for
special
reporting
of
2007
emissions
from
all
sources,
for
reasons
stated
in
preamble.

Previous
51.122
(
c),
(
d),
(
e)
Detailed
lists
of
data
elements
in
these
three
paragraphs
are
replaced
with
a
single
reference
to
Subpart
A.

Previous
51.122(
f)
Renumbered
as
(
d)

Previous
51.122(
g)
Renumbered
as
(
e)

Previous
51.122(
h)
Renumbered
as
(
f)
and
reduced
to
a
reference
to
Subpart
A.

Previous
51.122(
i)
Renumbered
as
(
g)
and
reduced
to
a
reference
to
definitions
in
Subpart
A.

51.125
New
section
This
new
section
states
the
emissions
reporting
requirements
related
to
the
Clean
Air
Interstate
Rule.
It
is
similar
in
structure
and
content
to
51.122.
30
