ENVIRONMENTAL
PROTECTION
AGENCY
40
CFR
Part
52
[
EPA­
R06­
OAR­
2005­
TX­
0018;
FRL
­
]

Approval
and
Promulgation
of
Air
Quality
Implementation
Plans;
Texas;
Revisions
to
the
Ozone
Attainment
Plan
for
the
Houston/
Galveston/
Brazoria
Nonattainment
Area
AGENCY:
Environmental
Protection
Agency
(
EPA).

ACTION:
Final
rule.

SUMMARY:
EPA
is
approving
revisions
to
the
Texas
State
Implementation
Plan
(
SIP)
as
it
applies
to
the
Houston/
Galveston/
Brazoria
(
HGB)
ozone
nonattainment
area.
These
SIP
revisions
result
from
more
recent
information
on
ozone
formation
in
the
HGB
area
indicating
that
a
combination
of
controls
on
nitrogen
oxides
(
NOx)
and
highly
reactive
volatile
organic
compounds
(
HRVOCs)
should
be
more
effective
in
reducing
ozone
than
the
measures
in
the
previously
approved
2001
HGB
attainment
demonstration
plan
which
relied
almost
exclusively
on
the
control
of
NOx.
Approval
of
these
revisions
incorporates
these
changes
into
the
federally
approved
SIP.

The
approved
revisions
include
a
1­
hour
ozone
standard
attainment
demonstration,
motor
vehicle
emissions
budgets,
a
demonstration
that
all
reasonably
available
control
measures
have
been
adopted
for
the
HGB
area
and
revisions
to
satisfy
the
enforceable
commitments
contained
in
the
previously
approved
SIP.
These
revisions
present
a
new
mix
of
controlled
strategies
in
order
2
to
achieve
attainment.
These
revisions
include
changes
to
the
industrial
NOx
rules,
reducing
the
stringency
from
a
nominal
90
percent
to
80
percent
control
and
revisions
to
the
Texas
Inspection
and
Maintenance
(
I/
M)
rules
that
drop
three
counties
from
the
I/
M
program.

As
part
of
the
approved
revisions
to
the
HGB
attainment
demonstration,
Texas
has
adopted
new
control
measures
which
EPA
has
approved
or
is
approving
concurrent
with
this
action.
The
new
control
measures
are
increased
control
of
HRVOC
emissions
and
control
of
emissions
from
portable
gasoline
containers.
Also,
in
separate
actions
in
today's
Federal
Register,

EPA
is
concurrently
approving
the
following
emissions
trading
programs
that
relate
to
the
HGB
attainment
demonstration:
revisions
to
the
Mass
Emissions
Cap
and
Trade
Program
for
the
HGB
area,
the
Highly
Reactive
Volatile
Organic
Compound
Emissions
Cap
and
Trade
Program
for
the
HGB
area,
the
Emissions
Credit
Banking
and
Trading
Program,
and
the
Discrete
Emissions
Credit
Banking
and
Trading
Program.

The
SIP
revisions
to
the
HGB
attainment
demonstration
addressed
in
this
rulemaking
along
with
the
HRVOC
rules
and
emissions
trading
programs
being
concurrently
approved,
will
provide
for
timely
attainment
of
the
1­
hour
ozone
standard
in
HGB
as
demonstrated
through
the
modeling
analysis.
Additionally,
Texas
has
shown
that
these
revisions
will
not
interfere
with
any
applicable
requirement
concerning
attainment
and
reasonable
further
progress,
or
any
other
applicable
requirement
of
the
Clean
Air
Act.
(
Section
110(
l)
demonstration).

DATES:
This
rule
is
effective
on
[
Insert
date
30
days
from
date
of
publication
in
the
Federal
Register].
3
ADDRESSES:
EPA
has
established
a
docket
for
this
action
under
Docket
ID
No.
EPA­
R06­

2005­
TX­
0018.
All
documents
in
the
docket
are
listed
on
the
www.
regulations.
gov
web
site.

Although
listed
in
the
index,
some
information
is
not
publicly
available,
e.
g.,
CBI
or
other
information
whose
disclosure
is
restricted
by
statute.
Certain
other
material,
such
as
copyrighted
material,
is
not
placed
on
the
Internet
and
will
be
publicly
available
only
in
hard
copy
form.

Publicly
available
docket
materials
are
available
either
electronically
through
www.
regulations.
gov
or
in
hard
copy
at
the
Air
Planning
Section
(
6PD­
L),
Environmental
Protection
Agency,
1445
Ross
Avenue,
Suite
700,
Dallas,
Texas
75202­
2733.
The
file
will
be
made
available
by
appointment
for
public
inspection
in
the
Region
6
FOIA
Review
Room
between
the
hours
of
8:
30am
and
4:
30pm
weekdays
except
for
legal
holidays.
Contact
the
person
listed
in
the
FOR
FURTHER
INFORMATION
CONTACT
paragraph
below
or
Mr.
Bill
Deese
at
214­
665­
7253
to
make
an
appointment.
If
possible,
please
make
the
appointment
at
least
two
working
days
in
advance
of
your
visit.
There
will
be
a
15
cent
per
page
fee
for
making
photocopies
of
documents.

On
the
day
of
the
visit,
please
check
in
at
the
EPA
Region
6
reception
area
at
1445
Ross
Avenue,

Suite
700,
Dallas,
Texas.

The
State
submittal,
which
is
part
of
the
EPA
record,
is
also
available
for
public
inspection
at
the
State
Air
Agency
listed
below
during
official
business
hours
by
appointment:

Texas
Commission
on
Environmental
Quality,
Office
of
Air
Quality,
12124
Park
35
Circle,

Austin,
Texas
78753.

FOR
FURTHER
INFORMATION
CONTACT:
Erik
Snyder,
Air
Planning
Section
(
6PD­
L),
4
Environmental
Protection
Agency,
Region
6,
1445
Ross
Avenue,
Suite
700,
Dallas,
Texas
75202­

2733,
telephone
214­
665­
7305;
fax
number
214­
665­
7263;
e­
mail
address
snyder.
erik@
epa.
gov.

SUPPLEMENTARY
INFORMATION
Throughout
this
document,
wherever
"
we",
"
us",
or
"
our"
is
used,
we
mean
the
EPA.

Table
of
Contents
I.
Final
Action
A.
What
Is
The
Background
For
This
Action?

B.
What
Action
Is
EPA
Taking?

C.
What
Other
SIP
Elements
Did
We
Need
to
Take
Final
Action
On
Before
We
Could
Approve
the
Revised
Attainment
Demonstration?

II.
What
Revisions
to
State
Implementation
Plan
Are
Being
Approved
Here
or
in
Other
Concurrent
Actions?

A.
One
Hour
Ozone
Attainment
Demonstration
B.
New
Control
Measures
C.
Control
Measures
Have
Been
Revised
or
Repealed
D.
Reasonably
Available
Control
Measures
E.
Section
110(
l)
Analysis
F.
Enforceable
Commitments
G.
Motor
Vehicle
Emission
Budgets.

III.
What
Is
EPA's
Response
To
Comments
Received
On
The
October
5,
2005
Proposed
Rulemaking
For
This
Action?
5
A.
What
Comments
Were
Received?

B.
Response
To
Comments
On
The
Attainment
Demonstration
IV.
Statutory
and
Executive
Order
Reviews
I.
Final
Action
A.
What
is
the
Background
for
this
Action?

On
October
5,
2005,
we
proposed
approval
of
the
revisions
to
the
SIP
as
it
applies
to
the
HGB
ozone
nonattainment
area
(
70
FR
58119).
The
proposal
provided
a
detailed
description
of
these
revisions
and
the
rationale
for
our
proposed
actions,
together
with
a
discussion
of
the
opportunity
to
comment.
The
proposed
HGB
attainment
demonstration
revisions
relies
upon
four
separate
actions
that
EPA
proposed
for
approval
on
October
5,
2005:
Highly
Reactive
Volatile
Organic
Compound
Emissions
Cap
and
Trade
Program
for
the
HGB
Ozone
Nonattainment
Area
(
70
FR
58138),
Discrete
Emission
Credit
Banking
and
Trading
Program
(
70
FR
58154),

Emissions
Banking
and
Trading
Revisions
for
the
Mass
Emissions
Cap
and
Trade
Program
for
the
HGB
Ozone
Nonattainment
Area
(
70
FR
58112),
and
a
Emission
Credit
Banking
and
Trading
Program
(
70
FR
58146).
The
public
comment
period
for
these
proposed
actions
closed
on
November
4,
2005.
One
adverse
comment
letter
and
one
comment
letter
supporting
our
action
were
received.
The
proposed
SIP
revision
also
relies
upon
a
separate
action
that
EPA
proposed
for
approval
on
April
7,
2005
(
70
FR
17640)
that
included
HRVOC
rules
requiring
sources
to
monitor
and
control
HRVOCs.
For
more
information,
see
the
Technical
Support
Documents
or
the
proposal
notices
for
the
attainment
demonstration
or
the
five
other
notices.
This
SIP
revision
6
also
relies
upon
a
separate
action
that
included
measures
controlling
emissions
from
portable
gasoline
containers
that
EPA
approved
on
February
10,
2005
(
70
FR
7041).

The
following
submissions
from
Texas
which
requested
revision
of
the
HGB
SIP
were
considered
for
this
action:

January
28,
2003:
This
submission
responded
to
the
State's
settlement
agreement
to
provide
an
accelerated
evaluation
of
whether
the
industrial
NOx
controls
could
be
substituted
with
controls
on
HRVOCs.
Based
on
the
study,
the
commission
adopted
rules
substituting
controls
on
NOx
emissions
from
industrial
sources
with
new
controls
on
HRVOCs.
Texas
also
adopted
a
number
of
minor
revisions
to
the
general
VOC
rules.
Finally,
the
State
also
provided
a
demonstration
that
Texas
Emission
Reduction
Program
(
TERP)
emission
reductions
would
be
sufficient
to
achieve
25
percent
of
the
NOx
reductions
needed
to
demonstrate
attainment,
i.
e.,

about
14
tons
per
day
(
tpd).

October
16,
2003:
This
submission
delayed
compliance
for
the
I/
M
program
in
Chambers,

Liberty
and
Waller
Counties.
(
Docket
EPA­
R06­
OAR­
2005­
TX­
0035)

October
6,
2004:
This
submission
repealed
the
I/
M
program
in
Chambers,
Liberty
and
Waller
Counties.
(
Docket
EPA­
R06­
OAR­
2005­
TX­
0035)

November
16,
2004:
This
submission
repealed
a
ban
on
morning
operations
of
lawn
service
contractors.

December
17,
2004:
This
submission
met
the
State's
commitment
to
provide
a
mid­
course
review
SIP.
Based
on
the
updated
analysis,
the
State
further
tightened
controls
on
HRVOCs
in
Harris
county
and
revised
or
repealed
a
number
of
NOx
control
measures
including,
the
vehicle
idling
prohibition,
the
speed
limit
strategy,
the
voluntary
mobile
emissions
program
and
the
7
commitment
to
achieve
NOx
reductions
beyond
the
initial
25
percent
provided
in
January
2003
(
i.
e.,
revoked
the
State's
enforceable
commitment
to
achieve
42
tpd
of
the
NOx
reductions
that
was
included
as
part
of
the
prior
attainment
demonstration).

B.
What
Action
Is
EPA
Taking?

We
are
approving
the
following
revisions
to
the
1­
hour
ozone
attainment
plan
for
the
HGB
area:

°
TCEQ's
revised
demonstration,
submitted
December
17,
2004,
that
the
1­
hour
ozone
standard
will
be
achieved
in
2007,
as
required
by
the
Texas
State
Implementation
Plan,
even
though
the
ozone
1­
hour
NAAQS
was
revoked
in
June
2005.

°
The
revised
motor
vehicle
emissions
budgets
associated
with
the
revised
attainment
demonstration.
The
revised
2007
budgets
are
89.99
tons
per
day
(
tpd)
for
volatile
organic
compound
emissions
and
186.13
tpd
for
NOx
emissions.

°
TCEQ's
revised
demonstration
that
all
reasonably
available
control
measures
have
been
adopted
for
the
HGB
area.

°
Revisions
to
satisfy
the
enforceable
commitments
contained
in
the
previously
approved
SIP
(
November
14,
2001,
66
FR
57160).
With
respect
to
its
original
enforceable
commitment
to
reduce
NOx
emissions,
TCEQ
has
instead
substituted
reductions
in
HRVOCs
for
a
portion
of
these
NOx
reductions
and
shown
that
the
HRVOC
reductions
provide
equivalent
air
quality
benefits
in
reducing
ozone
levels.

°
Revisions
to
the
industrial
NOx
rules
submitted
January
28,
2003,
which
included
several
miscellaneous
changes
and
the
reduction
in
stringency
from
a
nominal
90
percent
to
80
8
percent
control.

°
Revisions
to
the
Texas
I/
M
rules
that
drop
three
counties
from
the
I/
M
program.
In
addition,
several
miscellaneous
changes
are
approved.

°
Repeal
of
the
vehicle
idling
rule.

°
Repeal
of
the
Small
Spark
Engine
Operating
Restrictions.

°
Revisions
to
the
Speed
Limit
Strategy.

°
Revisions
to
the
voluntary
mobile
emissions
program.

Our
proposal
to
approve
the
revisions
was
published
in
the
Federal
Register
on
October
5,
2005
(
70
FR
58119).
Table
1
lists
the
revised
elements
of
the
HGB
ozone
SIP
we
are
approving
in
this
action.

TABLE
1. 
REVISED
ELEMENTS
OF
THE
HGB
OZONE
SIP
BEING
APPROVED
BY
EPA
Element
Date
Submitted
to
EPA
Comments
1­
hour
ozone
standard
attainment
demonstration
revisions.
12/
17/
04
Please
see
our
proposed
action
and
technical
support
document
for
more
information.

Revised
motor
vehicle
emissions
budgets
for
2007.
12/
17/
04
Revised
budgets
are
89.99
tpd
for
volatile
organic
compounds
and
186.13
tpd
for
NOx
.

Reasonably
available
control
measures
demonstration.
12/
17/
04
Please
see
our
proposed
action
and
technical
support
document
for
more
information.

Revisions
to
satisfy
the
enforceable
commitments
contained
in
the
previously
approved
SIP
(
November
14,
2001,
66
FR
57160).
12/
17/
04
Please
see
our
proposed
action
and
technical
support
document
for
more
information.
9
Revisions
to
the
industrial
NOx
rules
which
included
several
miscellaneous
changes
and
the
reduction
in
stringency
from
a
nominal
90%
to
80%
control.
1/
28/
03
Revisions
to
30
TAC
Chapter
117,
Sections
117.10,
117.105
­
117.108,
117.113
­
117.116,
117.119,
117.131,
117.135,
117.138,
117.141,
117.143,
117.149,
117.203,
117.205
­
117.207,
117.213
­
117.216,
117.219,
117.223,
117.301,
117.309,
117.311,
117.313,
117.319,
117.321,
117.401,
117.409,
117.411,
117.413,
117.419,
117.421,
117.463,
117.465,
117.473,
117.475,
117.478,
117.479,
117.510,
117.512,
117.520,
and
117.534.

Repeal
of
30
TAC
Chapter
117,
Sections
117.104,
117.540,
and
117.560.

Revisions
to
the
Texas
I/
M
rules
that
drop
three
counties
from
the
I/
M
program
and
make
several
miscellaneous
changes.
10/
6/
04
Revisions
to
30
TAC
Chapter
114,
Sections
114.1,
114.2,
114.50,
114.52,
and
114.53.

Repeal
of
the
vehicle
idling
rule.
12/
17/
04
Repeal
of
30
TAC
Chapter
114,
Sections
114.500,
114.502,
114.507,
and
114.509.

Repeal
of
the
Small
Spark
Engine
Operating
Restrictions.
11/
16/
04
Repeal
of
30
TAC
Chapter
114,
Sections
114.452
and
114.459.

Revisions
to
the
Speed
Limit
Strategy.
12/
17/
04
Please
see
our
proposed
action
and
technical
support
document
for
more
information.

Revisions
to
the
voluntary
mobile
emissions
program.
12/
17/
04
Please
see
our
proposed
action
and
technical
support
document
for
more
information.

Texas
has
adopted
a
revised
attainment
demonstration
that
includes
the
following
new
control
measures:

°
Hourly
(
short­
term)
limit
and
Annual
Cap
on
HRVOC
emissions.
10
°
Improved
requirements
for
HRVOC
Leak
Detection
and
Repair
Program
for
fugitive
emissions
and
flare
monitoring.

°
Requirements
for
portable
gasoline
containers.
(
EPA
approved
February
10,
2005).

We
approved
the
measure
controlling
emissions
from
portable
gasoline
containers
on
February
10,
2005
(
70
FR
7041).
The
SIP
revisions
addressed
in
this
rulemaking
in
conjunction
with
the
new
HRVOC
rules,
will
provide
for
timely
attainment
of
the
1­
hour
ozone
NAAQS
as
demonstrated
through
the
modeling
analysis.
In
addition,
Texas
has
shown
that
these
revisions
will
not
interfere
with
any
applicable
requirements
concerning
attainment
and
reasonable
further
progress,
or
any
other
applicable
requirement
of
the
Clean
Air
Act,
(
Section
110(
l)).

C.
What
Other
SIP
Elements
Did
We
Need
to
Take
Final
Action
On
Before
We
Could
Approve
the
Revised
Attainment
Demonstration?

In
our
proposed
action
we
explained
that
we
could
not
finalize
approval
of
the
revised
attainment
demonstration
for
HGB
until
we
finalized
approval
of
several
related
actions.
These
actions
are
discussed
below.
In
a
separate
rulemaking
published
in
this
issue
of
the
Federal
Register
we
are
approving
the
new
measures
to
control
HRVOC
emissions
as
part
of
the
basis
for
this
approval
of
revisions
to
the
HGB
attainment
SIP.
In
this
action,
when
we
refer
to
this
program
as
  
the
HRVOC
rule''
or
  
the
HRVOC
control
program'',
we
are
speaking
of
the
entire
rule
package
entitled
"
Control
of
Highly
Reactive
Volatile
Organic
Compound
Controls".

(
Docket
ID
No.
EPA­
R06­
OAR­
2005­
TX­
0033)
11
The
HRVOC
rules
were
adopted
by
TCEQ
based
on
recent
findings
that
certain
highly
reactive
chemicals
(
ethylene,
propylene,
1,3
butadiene
and
butenes)
contribute
disproportionately
to
the
ozone
problem
in
the
HGB
area.
EPA
previously
issued
a
proposed
approval
of
the
HRVOC
rules
on
April
7,
2005
(
70
FR
17640).

In
separate
rulemakings
published
in
today's
Federal
Register
we
are
approving
additional
measures
related
to
the
Revised
1­
hour
ozone
Attainment
Demonstration
for
HGB.
These
rules
include
the
HRVOC
Emissions
Cap
and
Trade
Program
for
the
HGB
ozone
nonattainment
area,

Discrete
Emission
Credit
Banking
and
Trading
Program
(
conditional
approval),
Emissions
Banking
and
Trading
Revisions
for
the
Mass
Emissions
Cap
and
Trade
Program
for
the
HGB
ozone
nonattainment
area,
and
an
Emissions
Credit
Banking
and
Trading
Program.
These
actions
are
further
discussed
in
Section
II.
B.
of
this
notice.

II.
What
Revisions
to
the
State
Implementation
Plan
Are
Being
Approved
Here
or
in
Other
Concurrent
Actions?

A.
One
Hour
Attainment
Demonstration:

As
required
by
the
Clean
Air
Act,
Texas
has
used
photochemical
grid
modeling
in
its
demonstration
that
the
control
strategy
for
the
HGB
area
will
achieve
attainment
of
the
1­
hour
ozone
NAAQS
by
2007.
Also,
as
allowed
for
under
EPA
policy,
TCEQ
has
introduced
other
evidence,
referred
to
as
weight
of
evidence,
to
supplement
the
modeling
analysis.
The
modeling
provided
in
the
mid­
course
review
SIP
revision
builds
on
modeling
performed
for
the
January
12
2003
SIP
revision
which
TCEQ
submitted
in
support
of
reducing
the
stringency
of
the
industrial
NOx
rules
and
adopting
measures
for
the
control
of
HRVOCs.

This
SIP
revision
actually
relies
on
two
sets
of
modeling
analyses.
First,
it
relies
on
modeling
performed
by
the
TCEQ
that
is
intended
to
simulate
the
routine
emissions
that
occur
in
the
HGB
area
and
determine
the
level
of
routine
emissions
that
can
be
allowed
in
the
area
yet
still
provide
for
attainment.
Second,
the
SIP
relies
on
modeling
that
was
provided
through
a
collaborative
effort
(
known
as
project
H13)
of
the
Houston
Advanced
Research
Center,
the
TCEQ,
the
University
of
Texas
and
the
University
of
North
Carolina.
The
project
H13
report
was
entitled,
"
Variable
Industrial
VOC
Emissions
and
Their
Impact
on
Ozone
Formation
in
the
Houston
Galveston
Area,"
April
16,
2004.
This
second
modeling
effort
was
used
to
estimate
the
impact
of
non­
routine
emission
events
on
ozone
levels.
This
two
pronged
approach
is
consistent
with
observations
that
indicate
that
Houston's
air
quality
problems
stem
from
the
combination
of
two
phenomena,
normal
routine
emissions
and
large
non­
routine
releases
of
HRVOC
emissions.

For
a
more
complete
description
of
the
modeling
procedures
and
EPA's
evaluation
of
these
procedures,
see
the
Technical
Support
Document
(
TSD)
in
the
Docket
for
this
action
(
RO6­

OAR­
2005­
TX­
0018)
and
the
FR
proposal
notice
October
5,
2005
(
70
FR
58119).

B.
New
Control
Measures:

TCEQ
has
adopted
the
following
new
control
measures
since
the
previously
approved
SIP
revision:

°
Hourly
(
short­
term)
limit
and
Annual
Cap
on
HRVOC
emissions.
13
°
Improved
requirements
for
HRVOC
Leak
Detection
and
Repair
Program
for
fugitive
emissions
and
flare
monitoring.

°
Requirements
for
portable
gasoline
containers.
(
EPA
approved
February
10,
2005).

1.
Hourly
(
short­
term)
limit
and
Annual
Cap
on
HRVOC
emissions.

As
discussed
in
the
proposal
notice
(
70
FR
58119)
and
Technical
Support
Document
(
TSD),
Texas
relied
primarily
on
two
sets
of
modeling
in
developing
its
control
strategy.
One
set
of
modeling,
performed
by
TCEQ,
is
largely
a
traditional
model
formulation
that
examines
the
routinely
variable
emissions
which
occur
in
the
HGB
area.
Through
this
modeling,
TCEQ
established
that
NOx
emissions
would
not
have
to
be
reduced
as
much
as
previously
planned
and
routine
emissions
of
highly­
reactive
VOC
emissions
would
have
to
be
reduced.
Through
the
second
set
of
modeling,
examining
the
impact
of
large
non­
routine
releases
of
HRVOCs,
it
was
established
that
the
frequency
and
magnitude
of
large
non­
routine
releases
of
HRVOCs
should
also
be
reduced.

Using
both
sets
of
modeling,
TCEQ
developed
a
key
feature
of
the
HGB
attainment
strategy:
routine
HRVOC
emissions
are
targeted
and
reduced
through
an
annual
cap­
and­
trade
program,
while
the
non­
routine
emissions
from
emission
events,
maintenance,
start­
up
and
shutdown
are
controlled
through
a
short­
term
limit
of
1200
lbs/
hour.
In
a
related
rulemaking
in
today's
Federal
Register,
EPA
is
concurrently
approving
the
Highly­
Reactive
Volatile
Organic
Compound
Emissions
Cap
and
Trade
Program
to
control
routine
emissions
of
HRVOCs
(
see
EPA­
R06­
OAR­
2005­
TX­
0033).
Unique
to
the
HGB
attainment
strategy,
exceedances
of
the
14
short­
term
limit
are
not
counted
toward
compliance
with
the
annual
cap
but
are
still
subject
to
enforcement
as
a
violation
of
the
short­
term
limit.

Again,
EPA
recognizes
that
the
approach
of
providing
this
partial
exclusion
for
emissions
above
the
short­
term
limit
is
a
departure
from
practices
in
other
cap
and
trade
programs
such
as
the
acid
rain
program
and
our
guidance.
We
currently
believe
this
approach
is
only
warranted
in
consideration
of
the
Houston
area's
unique
situation
that
combines
an
extensive
petrochemical
complex
and
the
availability
of
the
extensive
data
and
analysis
that
were
generated
by
the
intensive
ozone
study,
TxAQS
2000
and
in
conjunction
with
a
short­
term
limit.
Consideration
of
this
novel
approach
is
warranted
in
order
to
balance
the
need
to
reduce
both
routine
and
upset
emissions
of
HRVOC,
but
also
recognizes
that
large
upset
emissions
are
difficult
to
control
in
the
petrochemical
industry
and
one
significant
event
could
result
in
a
facility
consuming
more
than
a
month's
emission
allotment.

2.
Improved
requirements
for
HRVOC
Leak
Detection
and
Repair
Program
for
fugitive
emissions
and
flare
monitoring.

TCEQ
has
implemented
a
number
of
new
requirements
for
leak
detection
and
repair
of
components
in
HRVOC
service.
The
changes
include,
among
other
things,
the
following
improvements:

°
Inclusion
of
connectors
in
the
program.

°
Inclusion
of
other
non­
traditional
potential
leak
sources
such
as
heat
exchanger
heads
and
man­
way
covers.
15
°
Elimination
of
allowances
for
skipping
leak
detection
periods
for
valves.

°
Requirements
for
third
party
audits
to
help
insure
that
effective
leak
surveys
and
repairs
are
conducted.

°
Requirements
that
"
extraordinary"
efforts
be
used
to
repair
valves
before
putting
them
on
the
delay
of
repair
list.

For
purposes
of
estimating
emissions
for
compliance
with
the
Short­
term
and
annual
caps,

TCEQ
adopted
rules
requiring
companies
to
assume
specific
flare
destruction
efficiencies
for
properly
operating
flares
and
for
when
a
flare
operates
outside
the
parameters
of
40
CFR
60.18.

EPA
is
approving
the
estimates
used
for
flare
destruction
efficiency
for
use
in
the
attainment
demonstration
because
the
estimates
are
based
on
the
best
information
available.
We,
however,

remain
concerned
about
the
uncertainty
created
in
the
attainment
demonstration
by
having
a
significant
source
of
emissions
which
cannot
be
directly
measured.

We
note
that
some
operating
parameters
for
flares
such
as
steam
and
air
assist
ratios
are
not
covered
specifically
by
40
CFR
60.18
but
some
studies
have
indicated
these
parameters
can
impact
flare
efficiency.
Because
of
the
prevalence
of
flares
in
the
HGB
area,
we
believe
Texas
should
strongly
consider,
for
both
flares
in
HRVOC
service
and
general
VOC
service,

requirements
for
monitoring
steam
and
air
assist
ratios
to
insure
that
operators
maintain
these
parameters,
not
covered
by
40
CFR
60.18,
in
a
range
to
insure
optimum
combustion.
We
also
encourage
TCEQ
to
pursue
new
technology
such
as
the
Fourier
Transform
Infrared
Spectrophotometer
which
would
eventually
allow
the
direct
measurement
of
destruction
efficiency
in
the
field.
16
For
a
full
discussion
of
the
improvements
to
these
programs,
see
the
Proposal
Notice
and
Technical
Support
Document
for
this
action.
EPA
is
approving
the
emission
reductions
that
have
been
projected
for
the
improved
leak
detection
and
repair
rules.
Our
approval
is
based
on
the
improvements
to
the
fugitive
rule
and
Texas'
commitment
to
perform
a
rule
effectiveness
study
and
use
improved
emission
inventory
techniques
to
estimate
future
emissions
to
confirm
the
effectiveness
of
the
program.

3.
Requirements
for
Portable
Gasoline
Containers.

TCEQ
has
adopted
standards
for
portable
fuel
containers
sold
in
the
State
which
provide
requirements
to
prevent
leaks
and
spills.
EPA
approved
the
TCEQ
rules
on
February
10,
2005
(
70
FR
7041).
TCEQ
projected
2.9
tons/
day
of
VOC
emission
reductions
that
are
included
in
the
revised
attainment
demonstration
modeling.

C.
What
Control
Measures
have
been
Revised
or
Repealed?

Texas
has
revised
a
number
of
control
strategies
that
were
included
in
the
previously
approved
SIP.
A
brief
description
of
the
revisions
that
EPA
is
approving
follows.
More
details
are
provided
in
the
proposal
notice
(
70
FR
58119)
and
Technical
Support
Document
(
TSD)

materials.

Industrial
NOx
Controls:
Texas
revised
its
NOx
rules
to
reduce
the
controls
from
a
nominal
90
percent
control
to
80
percent
control.
We
are
approving
the
revisions
to
industrial
NOx
controls
in
the
HGB
area.
17
Vehicle
Inspection
and
Maintenance
Program
in
Three
Rural
Counties:
TCEQ
has
dropped
the
requirement
for
I/
M
in
Waller,
Liberty
and
Chambers
Counties.
We
are
approving
the
removal
of
the
I/
M
program
in
these
three
counties.

Removal
of
Small,
Spark­
Ignition
Engine
Operating
Restrictions:
TCEQ
has
dropped
this
requirement
which
would
have
prohibited
commercial
lawn
services
from
operating
during
the
morning
hours.
We
are
approving
the
removal
of
these
operating
restrictions
on
small,

spark­
ignition
engines.

Speed
Limit
Strategy
from
a
55
mph
Maximum
Speed
Limit
to
a
5
Mile
Reduction
in
Speed
Limits
from
Previous
Levels:
The
Texas
legislature
repealed
TCEQ's
authority
to
implement
speed
limits
for
environmental
purposes.
Texas
Department
of
Transportation
had
already
reduced
speeds
in
the
HGB
area
by
5
mph
from
70
mph
to
65
mph
and
from
65
to
60.

These
reductions
in
speed
limits
of
5
mph
remain
in
place,
but
the
reductions
that
would
have
been
achieved
by
reducing
speed
limits
on
all
roads
further
to
55
mph
will
not
be
achieved.

Removal
of
the
Vehicle
Idling
Restriction:
This
measure
that
would
have
prohibited
prolonged
idling
of
heavy
duty
diesel
vehicles
has
been
repealed.
We
are
approving
the
repeal
of
this
rule.

Revision
to
Delay
the
Compliance
Date
for
Gas
Fired
Water
Heaters
and
Small
Boilers:

This
rule
is
not
being
repealed,
but
its
compliance
date
has
been
delayed
from
December
31,
2004
to
January
1,
2007.
This
rule
requires
new
water
heaters
sold
in
Texas
to
achieve
lower
NOx
emission
rates.

We
are
not
approving
changes
to
the
rules
for
control
of
water
heaters
at
this
time.
It
is
a
Statewide
rule
and
the
changes
to
the
rule
impact
other
areas
of
the
State
and
we
have
not
yet
18
analyzed
the
above
issues
in
areas
of
the
State
other
than
Houston.
We
note
only
that
the
changes
to
the
water
heater
rules
do
not
impact
the
approvability
of
the
Houston
mid­
course
review
SIP
revision.

Revisions
to
the
Voluntary
Measures:
Texas
has
revised
the
voluntary
mobile
emissions
program
(
VMEP)
portion
of
the
SIP.
The
VMEP
portion
of
the
SIP
that
was
approved
in
2001,

and
was
projected
to
achieve
23
tpd
of
emissions
reductions
through
various
voluntary
and
often
innovative
measures.
TCEQ
has
recalculated
the
benefits
as
yielding
7
tpd
of
NOx
emission
reductions.
We
are
approving
the
revisions
to
the
VMEP.

D.
Reasonably
Available
Control
Measures:

A
brief
description
of
the
Reasonably
Available
Control
Measures
(
RACM)
revisions
follows,
for
more
details
see
the
proposal
notice
(
70
FR
58119)
and
Technical
Support
Document
(
TSD)
materials.

In
EPA's
November
14,
2001
notice
approving
the
plan
for
the
HGB
nonattainment
area,

EPA
approved
the
analysis
showing
the
plan
was
implementing
all
Reasonably
Available
Control
Measures.
The
NOx
reduction
requirements
of
that
plan
were
so
substantial
no
additional
RACM
measures
could
be
identified
in
time
for
adoption
as
a
part
of
that
plan
and
the
State
had
to
make
an
enforceable
commitment
to
adopt
additional
NOx
measures
which
were
expected
to
be
feasible
in
the
near
future.
Now,
based
on
the
findings
of
the
mid­
course
review,
Texas
has
determined
that
the
NOx
reductions
necessary
for
attainment,
while
still
substantial,
are
not
as
great
and
that
19
control
of
HRVOCs
is
a
more
effective
way
of
reducing
ozone.
Both
NOx
and
HRVOC
controls,

necessary
for
attainment,
will
be
fully
implemented
the
last
year
of
the
strategy.
In
the
last
year
of
the
strategy,
the
point
source
controls
alone
will
achieve
an
estimated
39
tpd
of
NOx
reductions
(
based
on
review
of
the
TCEQ's
Mass
Cap­
and­
Trade
Registry).
Reductions
in
onand
off­
road
emissions
will
also
occur.
Therefore,
to
advance
attainment,
additional
reductions
on
the
order
of
39
tpd
would
have
to
be
achieved
before
the
ozone
season
of
2006.
In
Section
5.4
of
the
State
Implementation
Plan,
Texas
explains
why
even
with
the
repeal
and
revision
of
the
measures,
Texas
believes
the
RACM
requirement
is
still
being
met.
What
follows
is
a
brief
summary
of
EPA's
evaluation
of
each
of
the
revisions
being
approved.

Industrial
NOx
Controls:
TCEQ
has
relaxed
the
NOx
rules
for
a
number
of
NOx
point
source
categories.
The
original
controls
achieved
a
nominal
90%
reduction
in
point
source
emissions,
with
some
categories
reducing
more
than
90%
and
some
less
than
90%.
The
new
rules,
being
approved
here
today,
achieve
a
nominal
80%
control.
It
is
a
convenient
short
hand
to
refer
to
the
control
levels
as
90%
or
80%
even
though
this
does
not
accurately
state
the
level
of
reduction
for
individual
source
categories.
TCEQ
has
argued
that
the
90%
controls
would
not
advance
attainment
because
the
current
80%
control
levels
are
scheduled
to
be
implemented
in
2007
and
it
would
not
be
reasonable
to
expect
that
a
more
stringent
90%
control
could
be
implemented
faster
to
advance
attainment.
EPA
previously
agreed
that
the
most
expeditious
schedule
for
the
90%
controls
would
be
by
2007.
EPA
continues
to
believe
that
to
be
the
case
so
that
implementation
of
90%
controls
would
not
advance
attainment.
Even
at
the
80%
control
level,
the
TCEQ
rules
are
still
similar
in
stringency
to
the
control
levels
implemented
in
California
which
have
generally
been
considered
the
most
stringent
in
the
country.
20
Repeal
of
the
I/
M
Program
in
3
Rural
Counties:
Texas
has
chosen
to
reduce
the
scope
of
its
I/
M
program
from
eight
counties
to
five
counties.
The
three
counties
that
are
being
dropped
are
Chambers,
Liberty
and
Waller
Counties
which
are
the
most
rural
counties
in
the
nonattainment
area.
The
program
was
scheduled
to
be
implemented
in
2005.
Using
Mobile6,
Texas
has
estimated
that
the
program
would
achieve
0.87
tpd
of
emission
reductions
which
is
a
smaller
reduction
estimate
than
the
Mobile
5
estimate
included
in
the
2000
SIP
and
is
less
than
0.2
%
of
the
projected
emissions
for
the
area
in
2007.
Because
of
the
small
amount
of
emission
reductions,
implementation
of
I/
M
in
these
three
counties
would
not
be
expected
to
advance
attainment
and
therefore
should
not
be
considered
RACM.

Removal
of
Small
Spark
Operating
Restrictions:
This
measure
would
prohibit
lawn
and
garden
service
contractors
for
operation
in
the
morning
hours
from
6
am
to
10
am.
This
measure
was
due
to
be
implemented
in
2005.
Texas
decided
that
attainment
could
be
reached
without
the
implementation
of
this
measure.
The
measure
was
estimated
to
achieve
the
equivalent
of
7.7
tons/
day
of
NOx
emission
reductions.
As
such,
its
implementation
would
not
advance
the
attainment
date.
Therefore,
EPA
believes
the
morning
lawn
service
ban
should
not
be
considered
a
reasonably
available
control
measure
for
the
HGB
area.

Speed
Limit
Strategy:
The
previously
approved
SIP
provides
for
the
speed
limits
in
the
eight
county
area
to
be
reduced
to
55
mph.
Later,
TCEQ
decided
to
delay
the
implementation
of
the
55
mph
until
2005,
but
would
implement
speed
limits
that
are
5
mph
lower
than
the
previous
speed
limits,
lowering
70
mph
speed
limits
to
65
mph
and
65
mph
limits
to
60
mph
starting
in
2001.
In
the
2004
SIP
revision,
TCEQ
decided
to
make
permanent
the
interim
limits
and
forgo
21
lowering
the
speed
limits
to
55
mph.
Based
on
Mobile
6,
lowering
speeds
all
the
way
to
55
mph
would
be
expected
to
reduce
emissions
2­
3
tons/
day.
This
is
a
lower
estimate
of
emission
reductions
than
predicted
by
Mobile
5
in
the
2000
SIP
revision.
This
small
amount
of
emission
reduction
would
not
advance
attainment
in
the
Houston
area
and
therefore
this
measure
is
not
considered
RACM.

Vehicle
Idling
Restriction:
Texas
is
dropping
a
rule
that
prohibits
idling
of
heavy
duty
vehicles
for
more
than
five
minutes
in
the
Houston
area.
The
measure
was
estimated
to
reduce
NOx
emissions
by
0.48
tpd.
Texas
decided
that
attainment
could
be
reached
without
the
implementation
of
this
measure.
This
small
amount
of
emission
reduction
would
not
advance
attainment
for
the
area
and
therefore
should
not
be
considered
RACM.

Delay
in
Compliance
for
the
Water
Heater
Rule:
In
this
case,
TCEQ
still
intends
to
implement
the
rule,
but
has
delayed
compliance
until
2007.
Since
the
adoption
of
the
current
rule,

two
American
National
Standards
Institute
(
ANSI)
standards
(
the
flammable
vapor
ignition
resistance
standard
and
the
lint,
dirt,
and
oil
standard);
the
United
States
Department
of
Energy
(
DOE)
energy
efficiency
standard;
and
the
EPA
insulation
foam
ban
have
been
implemented.
The
ANSI
lint,
dirt,
and
oil
standard
and
the
flammable
vapor
ignition
resistance
standard
were
effective
on
July
1,
2003,
and
were
established
for
gas­
fired
water
heater
safety
reasons.
The
DOE
energy
efficiency
standard
was
effective
on
January
20,
2004.
The
EPA
foam
ban
was
effective
on
January
1,
2003,
and
affects
gas­
fired
water
heaters,
as
water
heater
manufacturers
have
historically
used
hydrochlorofluorocarbon
as
a
blowing
agent
for
creating
foam
insulation.

The
implementation
of
these
standards
has
delayed
the
progression
of
the
water
heater
technology
22
and
design.
Therefore,
a
design
that
meets
the
10
ng/
J
emission
limit
in
the
Texas
rule
will
not
be
available
for
sale
in
the
market
by
the
January
1,
2005
compliance
date.

Because
the
new
federal
standards
affect
the
design
of
new
water
heaters
and
have
made
it
impractical
for
the
industry
to
meet
Texas's
NOx
limits
for
water
heaters
in
a
timely
manner,
EPA
agrees
that
this
measure
is
being
implemented
as
expeditiously
as
is
technically
practicable.
In
other
words,
earlier
implementation
is
not
technically
practicable
and
therefore,
since
it
would
be
infeasible,
it
would
not
advance
attainment.

We
have
reviewed
these
changes
in
RACM
that
are
summarized
above
and
discussed
these
changes
in
greater
detail
in
our
TSD.
We
are
approving
these
changes
to
RACM
as
part
of
the
approval
of
this
attainment
demonstration
revision
approval
and
determining
that
TCEQ
has
satisfied
the
RACM
requirements.

E.
Section
110(
l)
Analysis
A
brief
description
of
the
110(
l)
analysis
follows,
for
more
details
see
the
proposal
notice
(
70
FR
58119)
and
Technical
Support
Document
(
TSD)
materials.
Section
110(
l)
of
the
Clean
Air
Act
says:

"
Each
revision
to
an
implementation
plan
submitted
by
a
State
under
this
Act
shall
be
adopted
by
such
State
after
reasonable
notice
and
public
hearing.
The
Administrator
shall
not
approve
a
revision
of
a
plan
if
the
revision
would
interfere
with
any
applicable
requirement
concerning
attainment
and
reasonable
further
progress
(
as
defined
in
section
23
171),
or
any
other
applicable
requirement
of
this
Act."

As
previously
discussed,
Texas
has
developed
a
revised
strategy
which
relies
on
fewer
reductions
of
NOx
and
more
reductions
of
VOC.
Texas
determined
that
the
revisions
will
not
interfere
with
attainment
or
reasonable
further
progress
or
any
other
applicable
requirement
under
the
Act
and
after
careful
review,
EPA
agrees.
Texas
has
completed
the
revised
attainment
demonstration
with
respect
to
the
1­
hour
standard
which
is
being
approved
today.
Attainment
demonstrations
for
the
8­
hour
standard
are
not
required
until
June
2007.

Prior
to
the
time
that
attainment
demonstrations
are
due
for
the
8­
hour
ozone
standard,
it
is
unknown
what
suite
of
control
measures
a
State
will
choose
to
adopt
for
a
given
area
to
attain
that
standard.
During
this
period,
to
demonstrate
no
interference
with
the
8­
hour
NAAQS,
EPA
believes
it
is
appropriate
to
allow
States
to
substitute
equivalent
emission
reductions
(
to
compensate
for
control
measures
being
removed)
which
result
in
equal
or
greater
air
quality
benefit
than
those
reductions
being
removed
from
the
approved
SIP.
EPA
believes
that
preservation
of
the
status
quo
in
air
quality
during
the
time
in
which
new
attainment
demonstrations
are
being
developed
for
the
8­
hour
ozone
NAAQS
will
prevent
interference
with
the
States'
obligations
to
develop
timely
attainment
demonstrations
and
to
attain
as
expeditiously
as
practicable.

To
show
that
the
compensating
emission
reductions
are
equivalent,
modeling
or
adequate
analysis
must
be
provided.
The
compensating
emission
reductions
must
provide
actual,
new
emission
reductions
achieved
in
a
contemporaneous
time
frame
in
order
to
preserve
the
status
24
quo.
In
addition,
the
emission
reductions
must
be
permanent,
enforceable,
quantifiable,
and
surplus
to
be
approved
into
the
SIP.
EPA
has
determined
that
the
revised
HGB
SIP
has
met
each
of
these
requirements.
See
the
proposal
notice
(
70
FR
58119)
and
Technical
Support
Document
(
TSD)
materials.

Contemporaneous:
While
contemporaneous
is
not
defined
in
the
Clean
Air
Act,
a
reasonable
interpretation
is
that
the
compensating
control
measures
be
implemented
within
one
year
of
the
time
frame
for
the
control
measure
being
replaced.
In
this
case,
the
new
control
measures
being
used
as
substitutes
are
being
implemented
in
virtually
the
same
time
frames
as
the
measures
being
replaced.
The
new
measures
have
the
following
compliance
dates:
tighter
controls
on
HRVOC
fugitive
emissions
by
March
31,
2004,
monitoring
for
the
HRVOC
cap
by
2005,
compliance
with
the
HRVOC
cap
starting
in
2006,
and
gas
can
rule
implementation
in
2007.
The
measures
being
replaced,
which
are
listed
previously
in
this
notice,
with
the
exception
of
the
vehicle
idling
ban,
all
had
compliance
dates
in
the
approved
SIP
of
2005
or
later.
In
particular
the
largest
emission
reduction
change
by
far,
the
difference
between
90
percent
and
80
percent
control
on
NOx,
was
not
scheduled
to
be
fully
realized
until
2007.
The
enforceable
commitment
measures
only
provided
that
the
measures
would
be
adopted
by
May
2004
and
compliance
would
be
achieved
as
expeditiously
as
possible
but
no
later
than
the
beginning
of
the
ozone
season
in
2007.
Therefore,
it
can
be
assumed
the
emission
reductions
from
the
NOx
enforceable
commitments,
had
they
been
implemented,
would
not
have
occurred
before
the
2005­
2006
time
frame,
a
time
frame
similar
to
that
for
the
measures
to
control
HRVOCs
which
Texas
has
adopted
a
substitute.
With
regard
to
the
vehicle
idling
restrictions,

the
compliance
date
for
this
rule
was
May
of
2001.
It
was
projected
to
achieve
0.48
tpd
of
25
NOx
emission
reductions.
It
was
discontinued
effective
December
23,
2004.
The
improved
HRVOC
fugitive
controls
which
began
implementation
in
March
of
2004,
more
than
offset
the
small
reductions
lost
by
the
discontinuation
of
the
motor
vehicle
idling
program
after
December
23,
2004.

Equivalent:
To
demonstrate
that
the
emission
reductions
were
equivalent,
the
TCEQ
used
the
photochemical
model
to
demonstrate
that
the
total
collection
of
strategies
in
the
current
SIP
revision
is
equivalent
or
better
in
8­
hour
ozone
reduction
effectiveness
as
compared
with
the
total
collection
of
strategies
in
the
SIP
that
was
approved
in
2001,
including
the
reductions
that
would
have
occurred
due
to
measures
to
meet
the
enforceable
commitments.
Several
8­
hour
ozone
metrics
were
calculated.
EPA
believes
that
the
new
strategy
and
the
old
strategy
are
approximately
equivalent
in
8­
hour
ozone
benefit,
with
the
new
strategy
slightly
more
effective
in
reducing
the
peak
ozone
values
and
the
old
strategy
slightly
more
effective
in
reducing
the
predicted
area
of
exceedances.
Taking
all
of
the
metrics
into
consideration
and
recognizing
the
uncertainties
in
the
modeling,
we
believe
that
Texas
has
demonstrated
that
the
new
strategy
is
equivalent
to
the
old
strategy
in
8­
hour
ozone
benefit.

Permanent:
The
emission
reductions
from
the
HRVOC
rules
are
permanent
as
sources
will
have
to
maintain
compliance
with
new
measures
indefinitely.

Enforceable:
EPA
has
reviewed
the
enforceability
of
the
substitute
measures
in
separate
rules.

The
Portable
Fuel
Container
Rule
was
approved
:
February
10,
2005,
70
FR
7041.
EPA
is
also
approving
concurrently
in
a
separate
notice
the
fugitive
emission
controls
and
improved
26
monitoring
requirements
for
HRVOCs
(
proposal
on
April
7,
2005,
70
FR
17640)
.
Finally,

concurrent
with
this
Federal
Register
notice
EPA
is
approving
the
HECT
program.
In
each
of
these
rulemakings,
EPA
has
evaluated
whether
the
substitute
rules
are
enforceable,
considering
such
issues
as
whether
the
rules
have
adequate
test
methods,
monitoring
requirements,
record
keeping
requirements
and
whether
the
State
has
adequate
enforcement
authority
to
ensure
the
limits
are
achieved.
By
our
approval
elsewhere
in
the
Federal
Register
today,
these
substitute
rules
are
federally
enforceable
and
enforceable
by
the
public
through
citizen
suit.

In
summary,
we
believe
the
substitute
measures
result
in
equivalent
8­
hour
benefit
and
that
the
new
measures
are
contemporaneous,
enforceable
and
permanent.
Therefore,
we
believe
approval
of
these
revisions
to
the
approved
SIP
will
not
interfere
with
attainment
of
the
8­
hour
standard.

The
1­
hour
standard
was
revoked
on
June
15,
2005
for
the
HGB
area.
The
approved
SIP,
however,
committed
the
State
to
adopt
control
measures
of
56
tpd
of
NOx,
unless
the
State
could
show
that
these
NOx
reductions
were
not
needed
for
attainment
of
the
1­
hour
standard.
We
have
discussed
elsewhere
in
this
notice
(
and
in
the
proposal
and
TSD),
EPA's
evaluation
of
the
revised
1­
hour
attainment
demonstration
and
are
approving
these
revisions.

Texas
submitted,
and
EPA
has
approved,
revisions
to
the
rate
of
progress
(
ROP)
plan
(
February
14,
2005,
70
FR
7407)
based
on
the
revised
strategy.
These
revisions
will
ensure
that
1­
hour
ROP
is
met
for
each
three
year
period
out
to
the
1­
hour
attainment
date
of
November
15,
2007.
27
Other
than
for
ozone,
the
HGB
area
currently
meets
all
other
National
Ambient
Air
Quality
Standards.
The
plan
revisions
being
considered
would
not
be
expected
to
impact
compliance
with
the
CO,
SO
2
or
Lead
NAAQS
as
these
pollutants
are
not
affected
by
these
rules.

The
revisions
to
the
NOx
rules
do
affect
emissions
of
NO
2
and
thus
could
potentially
impact
attainment
with
the
NO
2
standard.
The
HGB
area,
however,
meets
the
NO
2
standard
at
today's
level
of
NO
2
emissions
and
the
revised
plan
will
reduce
NO
2
emissions
dramatically
from
existing
levels
and
thus
will
not
interfere
with
maintenance
of
the
NO
2
standard.

Similarly,
the
HGB
area
currently
meets
the
NAAQS
for
PM2.5.
NOx
and
VOCs
are
precursors
to
the
formation
of
PM2.5.
Although
the
revised
plan
does
not
reduce
NOx
emissions
as
much
as
the
previous
attainment
demonstration
SIP
revision
approved
by
EPA
in
November
2001,
the
revised
plan
will
result
in
additional
NOx
and
VOC
reductions
beyond
today's
levels
(
emission
levels
at
the
time
of
this
notice).
Therefore,
the
revised
plan
will
not
interfere
with
the
continued
attainment
of
the
PM2.5
standard.

Section
110(
l)
applies
to
all
requirements
of
the
Clean
Air
Act.
Below
are
requirements
potentially
affected
by
TCEQ's
rule
change
and
a
brief
discussion
of
EPA's
analysis.

Reasonably
Available
Control
Technology
(
RACT)
requirements:
EPA
has
previously
approved
the
NOx
and
VOC
rules
in
the
HGB
area
as
meeting
the
CAA's
RACT
requirements.

The
revised
NOx
rules
remain
substantially
more
stringent
than
the
previously
approved
RACT
28
requirements.
The
new
HRVOC
rules
build
on
the
previously
approved
RACT
requirements.

In
addition,
these
revisions
do
not
impact
the
major
sources
applicability
cutoffs.
Therefore,

these
revisions
do
not
interfere
with
the
implementation
of
RACT.

Inspection
and
maintenance
programs
(
I/
M):
This
revision
drops
three
counties
from
the
I/
M
program.
These
counties
are
not
included
in
the
urbanized
area
as
defined
by
the
Census
Bureau.
Thus,
I/
M
is
not
required
to
be
implemented
in
these
counties
and
these
revisions
do
not
interfere
with
meeting
the
I/
M
requirements
of
the
CAA.

Air
Toxics:
There
are
no
federal
ambient
standards
for
air
toxics
and
these
rules
do
not
interfere
with
implementation
of
any
federal
MACT
standards,
therefore,
these
rule
revisions
do
not
interfere
with
compliance
with
any
air
toxics
standards
under
sections
112
or
129
of
the
CAA.
We
note
that
air
toxic
levels
of
butadiene
and
formaldehyde
are
expected
to
decrease
as
a
result
of
the
revised
plan,
because
the
HRVOC
rules
directly
regulate
emissions
of
butadiene
and
ethylene.
Formaldehyde
is
formed
from
ethylene
in
the
photochemical
reactions
leading
to
ozone.

F.
Enforceable
Commitments
In
the
SIP
approved
in
November
2001,
there
were
enforceable
commitments
to
achieve
additional
NOx
reductions
and
enforceable
commitments
to
incorporate
the
latest
information
into
the
SIP.
This
section
contains
a
brief
summary
of
the
enforceable
commitments
which
were
approved
in
the
November
2001
Federal
Register
and
a
short
discussion
of
how
they
were
met
29
or
are
being
revised.

Commitment:
To
perform
a
mid­
course
review
(
including
evaluation
of
all
modeling,

inventory
data,
and
other
tools
and
assumptions
used
to
develop
this
attainment
demonstration)

and
to
submit
a
mid­
course
review
SIP
revision,
with
recommended
mid­
course
corrective
actions,
to
the
EPA
by
May
1,
2004.

Discussion:
Texas
provided,
in
the
December
2004
submission,
a
mid­
course
review
that
included
new
modeling
with
new
more
recent
episodes
(
including
updated
emissions)
based
on
the
Texas
2000
study.
The
State
submitted
control
measures
that,
based
on
the
demonstration,
will
result
in
attainment
of
the
1­
hour
standard
as
expeditiously
as
practicable.

Therefore,
EPA
believes
the
commitment
for
a
mid
course
review
has
been
satisfied.

Commitment:
To
perform
new
mobile
source
modeling
for
the
HG
area,
using
MOBILE6,
EPA's
on­
road
mobile
emissions
factor
computer
model,
within
24
months
of
the
model's
release.

Discussion:
The
mid­
course
review
modeling
employed
MOBILE6
for
the
on­
road
mobile
source
inputs
satisfying
this
commitment.

Commitment:
If
a
transportation
conformity
analysis
is
to
be
performed
between
12
months
and
24
months
after
the
MOBILE6
release,
transportation
conformity
will
not
be
determined
until
Texas
submits
an
MVEB
which
is
developed
using
MOBILE6
and
which
we
30
find
adequate.

Discussion:
This
commitment
was
not
applicable
because
transportation
conformity
was
not
performed
during
the
time
period.

Commitment:
To
adopt
rules
that
achieve
at
least
the
additional
56
tpd
of
NOx
emission
reductions
that
are
needed
for
the
area
to
show
attainment
of
the
1­
hour
ozone
standard,

including
the
adoption
of
measures
to
achieve
25%
(
14
tpd)
of
the
needed
additional
reductions
(
56
tpd),
and
to
submit
those
adopted
measures
to
EPA
as
a
SIP
revision
by
December
2002.

To
adopt
measures
for
the
remaining
needed
additional
reductions
and
submit
these
adopted
measures
to
EPA
as
a
SIP
revision
by
May
1,
2004.

Discussion:
In
the
January
28,
2003
submission,
TCEQ
provided
the
demonstration
that
the
TERP
program
meets
EPAs
requirements
as
an
economic
incentive
program
and
will
achieve
the
required
14
tons/
day
of
emissions
reductions.
EPA
has
approved
the
TERP
program
in
a
separate
Federal
Register
action
which
discusses
how
the
TERP
program
meets
the
EIP
requirements
(
August
19,
2005,
70
FR
48647
).
Through
the
attainment
year
of
2007,

38.8
tons/
day
of
emission
reductions
are
projected
for
the
TERP
program
based
on
a
$
5,000/
ton
cost
effectiveness.
The
total
obligation
for
emission
reductions
from
TERP
is
32.9
tpd.
TERP
originally
replaced
two
measures:
a
morning
construction
ban
(
6.7
tpd
NOx
equivalent)
and
accelerated
introduction
of
Tier
II/
III
equipment
(
12.2
tpd).
After
allocating
18.9
tpd
from
TERP
to
replace
these
two
measures,
the
program
still
is
projected
to
produce
an
additional
19.9
tpd
of
reductions
which
is
sufficient
to
provide
the
additional
14
tpd
of
31
emissions
reductions
needed
to
meet
the
enforceable
commitment.
Thus,
EPA
believes
the
enforceable
commitment
to
achieve
25%
of
the
56
tpd
of
NOx
reductions
has
been
satisfied.

We
note
two
developments
with
the
program.
The
average
cost
effectiveness
of
TERP
projects,
to
date,
is
$
5500/
ton
and
the
Texas
legislature
moved
to
cut
some
of
the
funding
for
the
program
in
the
last
session.
TCEQ
may
have
to
shift
some
of
the
TERP
funding
from
other
areas
such
as
Corpus
Christi
or
Victoria
,
which
currently
meet
the
8­
hour
ozone
standard,
to
the
HGB
area
to
insure
that
the
emission
reduction
targets
are
met.

For
the
rest
of
the
enforceable
commitments
to
adopt
and
submit
rules
to
achieve
the
remaining
42
tpd
NOx
reductions
due
by
May
1,
2004,
Texas
determined
that
these
additional
NOx
reductions
would
not
be
necessary
for
the
area
to
attain.
Instead,
as
discussed
elsewhere
in
this
document
and
the
proposed
approval
notice
(
70
FR
58119),
TCEQ
has
instead
adopted
and
has
begun
implementing
a
strategy
to
reduce
emissions
of
HRVOCs.
EPA
believes
that
the
new
strategy
will
attain
the
one­
hour
standard.
This
is
further
discussed
in
other
sections
of
this
notice,
the
proposal
notice,
and
the
TSD.

Commitment:
That
the
rules
will
be
adopted
as
expeditiously
as
practicable
and
the
compliance
dates
will
be
expeditious.

Discussion:
TCEQ
adopted
its
measures
for
the
control
of
HRVOC
first
in
2002
and
has
revised
them
three
times
since
then.
The
compliance
dates
in
the
rules
are
based
on
the
need
to
develop
monitoring
plans,
quality
assurance/
quality
control
programs,
install
the
32
monitors,
and
develop
control
plans
based
on
the
monitoring
results.
EPA
believes
that
the
implementation
of
these
new
measures
is
as
expeditious
as
practicable.

Commitment:
That
the
State
would
concurrently
revise
the
Motor
Vehicle
Emissions
Budgets
(
MVEBs)
and
submit
as
a
revision
to
the
attainment
SIP
if
additional
control
measures
reduce
on­
road
motor
vehicle
emissions.
Texas
stated
that
measures
which
could
limit
future
highway
construction,
such
as
growth
restrictions,
may
not
be
included.

Discussion:
Texas
has
revised
the
mobile
source
budget
to
account
for
TERP
reductions
and
other
adjustments
to
the
mobile
source
emissions
estimates.

Summary:
Based
on
the
above
analysis,
we
have
determined
that
TCEQ
has
satisfied
the
requirements
of
the
enforceable
commitments
contained
in
the
approved
Houston/
Galveston
SIP.

G.
Motor
Vehicle
Emissions
Budgets
The
MVEBs
established
by
this
plan
and
that
EPA
is
approving
are
contained
in
Table
2.

The
development
of
the
MVEBs
are
discussed
in
section
3.5
of
the
SIP
and
were
reviewed
in
the
TSD.
We
are
approving
the
new
MVEB
because
we
find
the
budget
to
be
consistent
with
the
attainment
plan.

Table
2:
2007
Attainment
Year
Motor
Vehicle
Emissions
Budgets
(
tons
per
day)
33
Pollutant
2007
VOC
89.99
NOx
186.13
III.
What
is
EPA's
Response
to
Comments
Received
on
the
October
5,
2005
Proposed
Rulemaking
for
This
Action?

A.
What
Comments
Were
Received?

The
following
comment
letters
were
received
on
the
October
5,
2005
proposal:

(
1)
November
4,
2005
letter
from
John
D.
Wilson,
Executive
Director
of
Galveston­
Houston
Association
for
Smog
Prevention
for
the
Galveston­
Houston
Association
for
Smog
Prevention,

Environmental
Defense
(
Texas
Office),
Lone
Star
Chapter
of
the
Sierra
Club,
and
Public
Citizen
(
Texas
Office).
Comments
from
this
group
will
be
referred
to
as
"(
Wilson)".

(
2)
November
4,
2005
letter
from
Matthew
L.
Kuryla
of
Baker
Botts
LLP
on
behalf
of
BCCA
Appeal
Group.
Comments
from
this
group
will
be
referred
to
as
"
commenter
(
BCCAAG)".

Commenter
BCCAAG
included
a
list
of
BCCA
Appeal
Group
members
as
follows:
Air
Products,
L.
P.;
Dynegy,
Inc.;
Entergy
Gulf
States,
Inc.;
Enterprise
Products
Operating,
L.
P.;

Exxon
Mobil
Corporation;
Greater
Fort
Bend
Economic
Development
Council;
Lyondell
Chemical
Company;
Reliant
Energy,
Inc.;
Shell
Oil
Company;
Texas
Genco;
Texas
Instruments
Incorporated;
Texas
Petrochemicals,
L.
P.;
and
Valero
Refining­
Texas,
L.
P.

B.
Response
to
Comments
on
Attainment
Demonstration
34
In
general
the
commenter
(
BCCAAG)
indicated
that
they
support
approval
of
the
proposed
attainment
demonstration
revisions
and
did
not
have
any
adverse
comments
on
this
SIP
revision.
They
indicated
that
the
revisions
represent
the
most
effective,
technically
and
scientifically
robust
plan
yet
advanced
for
achieving
air
quality
goals
in
the
HGB
airshed
and
the
revised
control
strategy
will
bring
the
area
into
attainment.
They
continued
by
indicating
that
the
revised
plan
is
already
reducing
the
number
of
days
that
ozone
exceedances
occur
and
the
magnitude
of
the
high
and
second
high
ozone
value
at
regulatory
monitors
has
decreased
substantially
in
the
last
three
years.
Commenter
(
BCCAAG)
supported
the
proposed
approval
indicating
that
the
revised
plan
did
meet
RACM
and
the
revised
control
strategy
would
reach
attainment.

1.
General
Comments:

Comment
GC1:
A
commenter
(
Wilson)
indicated
that
the
proposed
plan
fails
to
adequately
demonstrate
that
its
implementation,
maintenance,
and
enforcement
will
lead
to
attainment
of
the
1­
hour
national
air
ambient
quality
standards
(
NAAQS)
for
ozone
in
the
Houston­

Galveston­
Brazoria
(
HGB)
area.
State
ambient
monitoring
results
show
that
the
HGB
area
already
has
failed
the
test
for
attainment
of
the
1­
hour
ozone
standard
by
the
statutory
deadline
of
November
15,
2007,
further
demonstrating
that
the
SIP
revision
is
"
substantially
inadequate
to
attain"
the
ozone
NAAQS
by
the
deadline
established
in
the
Clean
Air
Act
(
CAA).
Thus,
as
demonstrated
in
these
comments,
the
EPA
Administrator
must
find
that:
35
1
42
U.
S.
C.
§
7509(
a)(
1)
and
(
2).
2
42
U.
S.
C.
§
110(
k)(
5).
°
Texas
has
failed
to
satisfy
the
minimum
criteria
under
section
110(
k);
1
and
°
the
plan
is
substantially
inadequate.

Then,
based
on
these
findings,
the
Administrator
must
require
that
the
TCEQ
submit
a
revised
plan
demonstrating
attainment
within
no
more
than
18
months.
2
Commenter
(
Wilson)
also
urged
EPA
to
disapprove
the
attainment
plan
because
they
believe
the
plan
does
not
include
complete
modeling,
enforceable
versions
of
all
Reasonably
Available
Control
Measures
(
RACM)
and
a
control
strategy
sufficient
to
achieve
attainment.

The
commenter
(
Wilson)
went
on
to
say
because
they
believe
the
plan
should
be
disapproved,

EPA
must
commence
promulgation
of
a
Federal
Implementation
Plan
(
FIP).

Response
GC1:
In
the
following
responses,
we
address
the
specific
concerns
raised
by
the
adverse
comments
in
more
detail.
We
believe
the
revised
plan
provided
by
the
State
of
Texas
is
fully
approvable
under
the
Act,
as
we
have
documented
in
this
notice
and
will
provide
for
attainment
as
expeditiously
as
practicable
which
is
by
November
15,
2007,
and
that
the
revised
plan
includes
all
reasonably
available
control
measures.
Therefore,
we
are
finalizing
our
approval
in
this
action.
Furthermore,
because
we
are
fully
approving
the
plan
as
meeting
the
requirements
of
182(
c)(
2)
and
(
d)
of
the
Act,
it
is
unnecessary
to
commence
development
of
a
FIP.

Comment
GC2:
Commenter
(
Wilson)
indicated
TCEQ
has
not
provided
modeling
that
shows
36
attainment
by
2007.
The
commenter
also
indicated
that
six
monitors
in
the
area
have
already
had
four
to
six
exceedances
of
the
1­
hour
ozone
NAAQS
and
the
area
has
already
failed
to
attain
by
November
17,
2007
based
on
monitoring
data
for
2005.
The
commenter
also
contended
that
two
one­
year
extensions
are
specifically
restricted
to
the
dates
listed
in
Table
1
of
Section
7511(
a)(
1),
and
that
they
do
not
apply
to
the
Severe­
17
area
deadlines
set
in
Section
7511(
a)(
2).
Therefore,
the
commenter
argues,
these
extensions
cannot
change
the
attainment
date
of
Severe­
17
areas
such
as
Houston.
The
commenter
also
states
that
there
is
no
demonstration
of
maintenance
of
the
ozone
standard
below
the
0.12
ppm
one­
hour
standard
beyond
2007.

Response
GC2:
EPA
has
taken
the
position
that
for
nonattainment
areas
subject
to
the
requirements
of
subpart
2
of
Part
D
of
the
Act,
the
area
needs
to
demonstrate
that
in
the
attainment
year,
the
area
will
have
air
quality
such
that
the
area
could
be
eligible
for
the
two
one­
year
extensions
provided
under
Section
181(
a)(
5)
of
the
Act.
See
66
FR
57160,
57163­
64
(
November
14,
2001).
EPA
disagrees
that
Severe­
17
areas
such
as
Houston
are
not
entitled
to
the
extensions
provided
in
Section181(
a)(
5).
It
is
our
interpretation
that
the
Severe
category
in
Table
1
of
Section
181(
a)(
1)
encompasses
both
Severe­
17
and
Severe­
15
areas.
Table
1
sets
an
attainment
date
of
15
years
for
severe
areas
with
a
1988
ozone
design
value
between
.180
and
.280
ppm.
However,
Section
181(
a)(
2)
of
the
Act
modifies
Table
1
to
provide
an
attainment
date
of
17
years
for
severe
areas
with
a
design
value
of
between
.190
and
.280
("
Severe­
17
areas").
For
those
areas
with
a
design
value
above
.190,
Congress
plainly
intended
to
allow
two
years
longer
to
attain
than
the
remainder
of
the
severe
areas
included
in
Table
1.
Table
1
in
Section
181(
a)(
1)
cannot
be
read
in
isolation,
and
must
be
read
in
conjunction
with
Section
37
181(
a)(
2).
EPA
thus
interprets
Section
181(
a)(
5)
as
providing
for
attainment
date
extensions
for
all
severe
areas,
including
those
whose
attainment
date
in
Table
1
is
modified
by
Section
181(
a)(
2).

EPA
interprets
Section
181(
a)(
2)
as
simply
recognizing
that
Severe
areas
with
a
higher
design
value
will
need
additional
time
to
reach
attainment
and
thus
is
simply
extending
the
date
in
Table
1
for
severe
areas
with
high
design
values.
There
is
nothing
in
Section
181
that
directly
excludes
Severe­
17
areas
from
the
extensions
provided
for
in
Section181(
a)(
5).
The
commenter
seems
to
suggest
that
even
though
Congress
recognized
that
Severe­
17
areas
would
need
more
time
to
reach
attainment,
they
are
not
entitled
to
the
extensions
in
Section
181(
a)(
5).

This
interpretation
would
result
in
the
Severe­
17
areas
getting
no
more
time
to
attain
than
Severe­
15
areas
that
potentially
could
qualify
for
the
two
one­
year
extensions.
This
would
be
an
absurd
result.
Under
the
commenter's
interpretation,
all
areas,
including
those
designated
"
Extreme",
would
be
entitled
to
attainment
date
extensions,
with
the
sole
exception
of
Severe­
17
areas.
This
would
mean
that
severe
areas
with
design
values
under
.190
would
be
allowed
two
one­
year
extensions,
providing
them
with
an
attainment
period
of
up
to
17
years,

while
the
Severe­
17
areas,
which
were
intended
to
have
two
years
longer
to
attain
than
the
other
severe
areas,
would
be
held
to
their
initial
17­
year
attainment
period,
thereby
eliminating
the
very
distinction
between
the
areas
that
Congress
intended
in
section
181(
a)(
2).
The
better
reading
is
that
Severe­
17
areas
should
be
eligible
for
the
2
one­
year
extensions
(
if
they
qualify
for
them)
provided
for
in
Section181(
a)(
5).
EPA
has
consistently
taken
this
position.
Indeed,

in
the
approval
of
the
full
attainment
demonstration
SIP
for
the
Houston
area
in
our
November
14,
2001
(
66
CFR
57160,
57163),
we
indicated
in
a
response
to
a
comment
(
that
the
modeling
38
should
show
attainment
in
2005)
that
EPA's
modeling
guidance
provided
for
modeling
to
demonstrate
attainment
in
the
last
year
(
2007
in
this
case)
such
that
it
would
be
eligible
or
clean
data
extensions
in
accordance
with
Section
181(
a)(
5).
It
has
been
EPA's
opinion
at
least
since
2001
that
Houston,
a
Severe­
17
area,
was
entitled
to
the
extensions
in
question.
If
the
commenter's
interpretation
was
applied
(
interpret
181(
a)(
5)
as
not
applying
to
Severe­
17
areas),

three
years
of
data
(
2005­
7)
would
be
needed
to
yield
attainment
in
2007
and
to
yield
those
monitor
levels,
EPA
would
have
had
to
modify
modeling
guidance
and
required
TCEQ
to
model
2005
future
year
for
Houston
and
show
no
exceedances
in
the
SIP
revisions
EPA
approved
in
2001.
Once
again,
if
the
commenter's
assertion
were
correct,
Severe­
17
areas
would
not
be
eligible
for
clean
data
extensions
with
the
end
result
being
an
attainment
date
not
much
different
than
if
the
area
had
been
designated
a
Severe­
15
area.

In
addition,
under
EPA's
interpretation,
a
Severe­
17
area
does
not
automatically
get
the
extensions.
They
have
to
demonstrate
significant
progress
towards
attainment.
Nonattainment
areas
subject
to
the
requirements
of
subpart
2
of
part
D
of
the
Act,
need
to
demonstrate
that
in
the
attainment
year,
the
area
will
have
air
quality
such
that
the
area
could
be
eligible
for
the
two
one­
year
extensions
provided
under
section
181(
a)(
5)
of
the
Act.
Under
section
181(
a)(
5),
an
area
that
does
not
have
three
years
of
data
demonstrating
attainment
of
the
ozone
NAAQS,
but
has
complied
with
all
of
the
statutory
requirements
and
that
has
no
more
than
one
exceedance
of
the
NAAQS
in
the
attainment
year,
may
receive
a
one­
year
extension
of
its
attainment
date.

Assuming
those
conditions
are
met
the
following
year,
the
area
may
receive
an
additional
one­
year
extension.
If
the
area
has
no
more
than
one
exceedance
in
this
final
extension
year,

then
it
will
have
three­
years
of
data
indicating
that
it
has
attained
the
ozone
NAAQS.
There
is
39
no
reason
to
believe
that
Congress
did
not
intend
for
Severe­
17
areas
to
exercise
this
option.

Moreover,
EPA
believes
this
approach
is
consistent
with
the
statutory
structure
of
subpart
2.
Under
subpart
2,
many
of
the
planning
obligations
for
areas
were
not
required
to
be
implemented
until
the
attainment
year.
Thus,
Congress
did
not
assume
that
all
measures
needed
to
attain
the
standard
would
be
implemented
three
years
prior
to
the
area's
attainment
date.
For
example,
areas
classified
as
marginal
 
which
had
an
attainment
date
of
three
years
following
enactment
of
the
1990
Clean
Air
Act
Amendments
­
were
required
to
adopt
and
implement
RACT
and
I/
M
"
fix­
ups"
that
clearly
could
not
be
implemented
three
years
prior
to
their
attainment
date.
Similarly,
moderate
areas
were
required
to
implement
RACT
by
May
1995,

only
18
months
prior
to
their
attainment
date
of
November
1996.
Also,
the
ROP
requirement
for
moderate
and
above
areas,
including
the
15%
plan
for
reductions
by
November
1996,

applies
through
the
attainment
year.
Thus,
EPA
believes
that
Congress
did
not
intend
that
these
additional
mandatory
reductions
be
in
excess
of
what
is
needed
to
achieve
three
years
of
"
clean
data."
EPA
does
not
require
areas
to
demonstrate
that
the
area
will
have
three
years
of
data
(
2005­
2007)
showing
attainment
in
the
attainment
year.
However,
EPA
does
believe
that
the
Act
requires
and
that
it
is
prudent
for
States
to
implement
controls
as
expeditiously
as
practicable.
As
discussed
elsewhere
in
this
notice,
additional
reductions
are
being
made
in
the
Houston
area
after
the
2005
ozone
season,
so
it
is
still
possible
for
the
additional
measures
to
result
in
the
area
reaching
attainment
by
2007.
For
these
reasons,
EPA
does
not
agree
with
the
commenter
that
the
State's
attainment
demonstration
is
inadequate
because
of
the
exceedances
that
occurred
at
six
monitors
in
2005.
40
A
plan
for
maintenance
of
the
NAAQS
is
not
necessary
for
the
attainment
demonstration
to
be
approved.
A
State
is
not
required
by
the
Act
to
provide
a
maintenance
plan
until
the
State
petitions
for
an
area
to
be
redesignated
to
attainment.
While
it
is
not
necessary
for
the
State
to
provide
for
maintenance
of
the
standard
at
this
time,
we
do
believe
emissions
in
the
HGB
area
will
continue
to
decrease
after
2007
due
to
on­
and
off­
road
vehicle
emission
control
programs
that
will
provide
additional
reductions
as
the
fleet
continues
to
turnover
after
2007.
TCEQ
is
also
required
to
provide
an
8­
hour
ozone
attainment
SIP
for
the
HGB
area
that
will
likely
require
a
new
mixture
of
control
measures
to
demonstrate
future
attainment
of
the
8­
hour
ozone
standard.
So
there
is
reason
to
believe
that
air
quality
will
continue
to
improve
after
the
1­
hour
attainment
date.

Comment
GC3:
Commenter
(
Wilson)
suggested
the
plan
should
address
other
air
pollution
concerns
such
as
reasonable
further
progress
of
the
8­
hour
standard
in
addition
to
attainment
of
the
one­
hour
standard.
The
commenter
suggested
the
plan
should
provide
as
much
progress
as
possible
toward
implementing
the
8­
hour
standard
as
the
requirements
of
the
Act
and
EPA's
implementing
regulations
allow.

Response
GC3:
EPA
established
submission
dates
for
8­
hour
SIPS
in
its
Phase
2
ozone
implementation
rule
(
70
FR
71611).
SIPs
addressing
reasonable
further
progress
and
attainment
of
the
8­
hour
standard
are
due
in
2007
and
are
not
the
subject
of
this
rulemaking.

EPA's
review
here
is
focused
on
whether
the
submitted
plan
meets
the
statutory
requirements
for
attainment
of
the
one­
hour
ozone
standard,
and
doesn't
interfere
with
attainment
of
the
8­
41
hour
NAAQS.
In
reviewing
the
1­
hour
attainment
SIP,
EPA
did
consider
consistent
with
section
110(
l)
whether
this
SIP
revision
would
interfere
with
attainment
of
the
8­
hour
NAAQS.

Section
110(
l)
requires
that
any
plan
revision
not
interfere
with
any
applicable
requirement
concerning
attainment
and
reasonable
further
progress,
or
any
other
applicable
requirement
of
the
Act
42
U.
S.
C.
§
7410(
l).
As
provided
in
Section
II.
E,
EPA
concludes
that
these
revisions
will
not
interfere
with
attainment
or
progress
toward
attainment
of
the
8­
hour
ozone
NAAQS.

Comment
GC4:
The
commenter
(
Wilson)
indicated
the
EPA
should
reject
the
TCEQ
claim
that
the
SIP
revision
is
likely
to
lead
to
attainment
because
it
is
based
on
a
model
analysis
that
is
systematically
biased
towards
under
predicting
unhealthy
levels
of
ozone,
both
in
the
base
case
and
future
conditions.
The
commenter
continues
that
TCEQ
wrongly
claims
the
only
significant
reason
for
this
under
prediction
is
the
under
reporting
of
short­
term
emissions
by
industry
and
that
other
factors
exist
for
the
under
prediction
bias.
The
commenter
continues
that
because
the
TCEQ
did
not
recognize
the
other
factors
that
lead
to
the
under
prediction
bias
in
their
model,

that
the
plan
being
considered
by
EPA
lacks
remedies
for
each
of
these
factors.
The
commenter
gives
the
example
that
TCEQ
did
not
adopt
measures
to
regulate
VOCs
other
than
HRVOCs
and
that
TCEQ
even
repealed
some
general
VOC
control
measures
even
though
evidence
suggests
that
Other
VOCs
(
OVOCs)
are
a
factor
in
the
under
prediction
bias.
The
commenter
summarizes
that
since
such
additional
control
measures
are
lacking,
that
EPA
should
disapprove
the
revisions.

Response
GC4:
While
EPA
agrees
that
a
general
under
prediction
bias
exists
in
the
base
case
and
future
year
modeling,
we
disagree
that
this
is
grounds
for
disapproving
the
revisions.
EPA
42
believes
all
model
performance
measures
should
be
considered
and
there
is
no
rigid
criterion
for
model
acceptance
or
rejection
in
assessing
model
simulation
results
for
the
performance
evaluation.
As
recommended
by
EPA,
the
State's
model
performance
evaluations
for
the
selected
episode
included
diagnostic
and
sensitivity
analyses,
and
graphical
and
statistical
performance
measures.
The
model
performance
evaluation
included
statistical
measures
consisting
of
comparing
the
modeled
versus
monitored
ozone
that
were
mostly
within
the
suggested
limits
in
EPA's
guidance.
In
addition,
the
graphical
performance
of
the
model
for
the
episode
indicated
the
model
performed
fairly
well.
For
all
days
modeled,
the
combination
of
statistical
and
graphical
performance
was
deemed
sufficient
for
this
revision
package.

Sufficient
evidence
exists
that
the
episodic
emissions
that
occur
in
the
Houston
area
do
impact
the
model's
capacity
to
replicate
ozone
and
are
a
plausible
reason
for
much,
if
not
all
of
the
ozone
under
prediction
in
the
model.
While
some
evidence
exists
that
an
under
estimation
of
emissions
of
Other
VOCs
(
OVOCs
=
VOCs
other
than
HRVOCs)
may
exist
and
that
this
may
be
responsible
for
some
modeling
under
prediction,
the
research
to
answer
the
level
of
under/
over
estimation
of
OVOCs
and
how
to
allocate
such
adjustment
in
the
model
were
not
available
when
TCEQ
was
conducting
the
modeling
for
these
revisions.
Furthermore,
modeling
analyses
indicate
that
HRVOC
emission
releases
(
in
addition
to
the
normal
inventory)
could
result
in
higher
ozone
levels
that
would
be
as
high
as
monitored
values
and
would
seem
to
resolve
much
of
the
modeling
under
prediction
bias
issues.
While
an
under
estimation
of
OVOCs
may
also
be
part
of
the
reason
for
the
under
prediction
bias
in
the
model,
sufficient
analyses/
evidence
do
not
exist
to
specifically
quantify
any
level
of
bias
due
to
wrongful
estimation
of
OVOCs.
While
TCEQ
did
not
implement
additional
controls
on
OVOCs,
it
is
43
EPA's
technical
opinion
that
based
on
the
weight­
of­
evidence
and
the
modeling,
the
State's
revised
control
strategy
provides
for
attainment
by
November
15,
2007.

Comment
GC5:
The
commenter
(
Wilson)
indicated
that
the
plan
is
not
likely
to
lead
to
attainment
because
several
of
the
control
strategies
are
not
likely
to
be
as
effective
as
TCEQ
claims.
The
commenter
continues
that
EPA
should
not
approve
some
of
the
control
strategy
revisions
(
relaxation
of
NOx
controls)
in
order
to
maintain
a
higher
level
of
pollution
control
in
the
Houston
area.
In
other
parts
of
the
commenter's
package,
the
commenter
indicated
that
the
NOx
rule
revisions
should
not
be
approved.

Response
GC5:
It
is
EPA's
technical
opinion
that
based
on
the
modeling
results
and
the
additional
weight­
of­
evidence,
the
State's
revised
control
strategy
provides
for
attainment
of
the
1­
hour
ozone
NAAQS
by
November
15,
2007.
We
have
addressed
other
specific
comments
from
the
commenter
on
issues
related
to
why
the
control
strategies
may
not
be
as
effective
as
TCEQ
claims
elsewhere
in
the
response
to
comments.
The
Clean
Air
Act
gives
the
State
the
primary
authority
to
prepare
a
SIP
that
provides
for
implementation,
maintenance
and
enforcement
of
the
NAAQS
in
each
air
quality
control
region
and
to
determine
the
mix
of
control
measures
to
achieve
that
goal,
as
long
as
they
show
attainment
and
the
demonstration
meets
110(
l)
requirements.
EPA's
responsibility
is
to
review
SIPs
that
the
State
provides
and
either
approve
or
disapprove
the
revisions
based
on
their
meeting
the
requirements
of
the
Act.

EPA
has
reviewed
the
revised
SIP
and
has
determined
that
the
revisions
(
including
the
NOx
rule
revisions)
demonstrate
attainment
by
November
15,
2007.
44
Comment
GC6:
The
commenter
(
Wilson)
indicates
that
although
the
TCEQ
has
exercised
sound
scientific
judgment
in
responding
to
many
issues
that
have
arisen,
the
SIP
revision
is
also
characterized
by
a
pattern
of
avoiding
unwanted
findings
by
withholding
data,
applying
standards
selectively,
reaching
inconsistent
conclusions,
failing
to
conduct
critical
research,
and
unreasonably
dismissing
comments.
The
commenter
continues
that
these
actions
undermine
the
technical
credibility
of
the
SIP
revision
and
prejudice
its
findings.
The
commenter
indicates
that
EPA
should
conduct
its
own
analysis
of
available
data
and
apply
a
health­
protective
bias
whenever
more
than
one
argument
is
supported
by
the
available
data.

Response
GC6:
EPA
is
satisfied
with
the
technical
credibility
of
TCEQ's
finding.
As
discussed
in
the
response
to
comment
GC5,
TCEQ
is
responsible
for
developing
an
acceptable
implementation
plan.
TCEQ
continues
to
have
an
open
stakeholder
process
(
both
periodic
technical
and
planning
meetings
and
special
meetings).
EPA
encourages
TCEQ
to
continue
having
an
open
stakeholder
process
and
to
continue
to
share
as
much
information
(
analyses,

modeling,
proposed
regulations,
etc.)
as
possible
with
the
public/
stakeholders
and
allow
for
comments/
feedback
to
be
considered
in
the
SIP
development
process.
EPA
conducted
a
detailed
review
of
the
proposed
revisions
prior
to
proposing
approval
and
provided
detailed
review
of
the
modeling
and
weight­
of­
evidence
analysis
in
the
proposal
and
TSD.
EPA
has
also
considered
the
comments
received
during
the
proposal's
comment
period
and
has
determined
that
the
SIP
revisions
are
acceptable
and
EPA
is
approving
these
revisions
to
TCEQ's
SIP.

Comment
GC7:
A
commenter
(
Wilson)
indicated
that
TCEQ
has
failed
to
include
contingency
measures
in
the
HGB
ozone
SIP.
The
commenter
continues
that
TCEQ
has
claimed
they
satisfy
45
this
requirement
with
the
measures
to
be
implemented
in
2008,
since
the
measures
are
above
and
beyond
those
modeled
in
the
proposed
revision
and
include
additional
TERP
reductions.

The
commenter
contends
that
these
measures
are
not
sufficient
because
TCEQ
has
not
substantiated
how
they
are
sufficient
to
advance
attainment.

Response
GC7:
TCEQ
included
contingency
measures
in
the
SIP
revision
for
23.57
tpd
reduction
in
NOx
and
10.84
tpd
of
VOC
in
2008.
EPA
has
reviewed
the
proposed
contingency
measures
and
concluded
that
they
meet
the
level
of
reductions
necessary.
Historically,
EPA
has
recommended
that
contingency
measures
achieve
an
additional
3
percent
reduction
in
emissions.

(
57
FR
13511)
The
purpose
of
contingency
measures
is
to
ensure
continued
progress
while
the
area
moves
forward
to
adopt
additional
controls
needed
for
attainment
and
we
believe
an
additional
3
percent
achieves
that
purpose.
(
57
FR
13511)
We
are
uncertain
what
the
commenter
is
referring
to
when
it
suggests
that
contingency
measures
must
be
"
sufficient
to
advance
attainment"
but
note
that
term
is
not
used
in
the
statute
nor
has
EPA
ever
suggested
that
as
the
test
for
determining
the
adequacy
of
contingency
measures.
While
we
find
that
TCEQ
has
adequately
satisfied
the
contingency
measure
requirement,
ultimately
we
note
that
contingency
measures
for
failing
to
attain
the
1­
hour
standard
will
not
apply.
As
noted
in
the
Phase
1
Rule
to
Implement
the
8­
hour
ozone
NAAQS,
EPA
did
not
retain
1­
hour
contingency
measures
as
an
applicable
requirement
that
would
continue
to
apply
after
the
1­
hour
standard
is
revoked
(
i.
e.,
June
15,
2005
for
the
HGB
nonattainment
area).
EPA
also
further
noted
that
once
the
1­
hour
standard
was
revoked,
EPA
would
no
longer
make
determinations
whether
an
area
had
met
or
failed
to
meet
that
revoked
standard
and
thus
contingency
measures
would
not
be
triggered
even
if
adopted.
(
70
FR
30592,
May
26,
2005
at
page
30599)
46
Comment
GC8:
A
commenter
(
Wilson)
indicated
EPA
should
not
disregard
the
1­
hour
ozone
standard
in
light
of
the
new
8­
hour
standard.
The
commenter
indicated
that
an
analysis
of
the
historical
record
demonstrates
that
if
Houston
meets
the
1­
hour
standard,
the
public
will
be
protected
from
air
pollution
exposures
that
would
be
allowed
under
the
8­
hour
standard.
The
commenter
iterated
that
it
is
likely
to
be
true
that
for
much
of
the
rest
of
the
country
the
8­
hour
standard
can
reasonably
supplant
the
1­
hour
standard
and
in
Houston
the
8­
hour
standard
is
clearly
superior
to
the
1­
hour
standard
in
terms
of
public
health
benefits.
The
commenter
continued
that
the
1­
hour
standard
has
a
special
role
in
Houston
for
the
protection
of
public
health.
The
commenter
indicated
that
TCEQ
data
suggest
that
failing
to
attain
the
1­
hour
standard
will
leave
Houston
residents
with
exposure
to
ozone
at
levels
that
the
EPA
once
sought
to
prevent.
According
to
the
commenter's
analysis
of
days
when
either
the
1­
hour
and/
or
the
8­
hour
standard
were
exceeded
during
2000­
2003,
the
one­
hour
standard
was
the
only
standard
breached
on
about
7
percent
of
the
days
(
approximately
6
days/
year).
The
commenter
also
indicated
the
AQI
reaches
a
higher
value
based
on
the
one­
hour
standard
on
a
similar
number
of
days.
The
commenter
continued
by
indicating
a
singular
focus
on
the
8­
hour
standard
(
and
not
addressing
the
1­
hour
standard)
could
leave
Houston
residents
breathing
unhealthy
air
about
6
days
per
year
even
after
the
8­
hour
standard
is
attained.

The
commenter
continued
that
controlling
short­
term
exposures
to
ozone
is
important
as
many
scientific
studies
based
on
the
1­
hour
ozone
standard
report
increased
use
of
asthma
medication,
increased
emergency
room
visits
and
hospitalization
for
respiratory
problems,
even
at
levels
below
0.12
ppm
for
just
one
or
two
hours
with
affects
continuing
for
days
or
months
afterwards.
47
The
commenter
continues
that
EPA
has
always
viewed
the
1­
hour
and
8­
hour
standards
as
adequate
alternative
methods
for
protecting
public
health,
and
gave
consideration
to
establishing
a
standard
that
combined
both
1­
hour
and
8­
hour
measurements.
The
commenter
indicates
the
basis
for
revoking
the
1­
hour
ozone
standard
dates
back
to
a
1996
report
(
EPA,

Review
of
National
Ambient
Air
Quality
Standards
for
Ozone:
Assessment
of
Scientific
and
Technical
Information,
June
1996)
issued
by
EPA
staff
that
concluded
from
a
public
health
perspective,
a
1­
hour,
an
8­
hour
or
a
combined
standard
could
be
set
at
a
level
that
would
adequately
protect
public
health.
The
commenter
continues
that
the
report
did
not
explicitly
reject
a
combination
of
the
1­
hour
and
8­
hour
standards,
but
did
firmly
endorse
an
8­
hour
standard.
The
commenter
indicates
the
record
isn't
entirely
clear
as
to
why
a
combined
standard
was
not
the
initial
recommendation
of
staff
in
the
report,
but
it
seems
to
turn
on
the
word
"
efficient."

The
commenter
continues
that
EPA
concluded
later
that
year
in
a
report
(
US
EPA,

"
Responses
to
Significant
Comments
on
the
1996
Proposed
Rule
on
the
National
Ambient
Air
Quality
Standards
for
Ozone";
December
13,
1996),
based
on
modeling
of
ozone
exposures,

"
that
an
8­
hour
0.08
ppm
averaging
time
does
effectively
limit
both
1­
and
8­
hour
exposures
of
concern.
The
commenter
continues
that
subsequent
EPA
decisions
recognize
that
the
8­
hour
standard
might
not
effectively
protect
the
public
from
1­
hour
health
effects,
and
sought
to
retain
the
1­
hour
ozone
standard
until
attainment,
and
then
revoke
it
on
an
area­
by­
area
basis.
The
commenter
indicates
that
this
would
have
been
consistent
with
full
protection
of
public
health
and
administrative
efficiency.
48
The
commenter
continued
that
the
EPA
decided
for
legal
reasons
to
go
ahead
and
revoke
the
1­
hour
standard
nationwide
while
California's
current
review
of
its
state
ozone
standards
is
likely
to
lead
to
a
1­
hour
standard
of
0.09
ppm,
compared
to
the
current
0.12
ppm
standard
used
by
EPA.

The
commenter
concluded
if
the
plan
EPA
proposes
to
approve
fails,
Houston
could
still
have
serious
public
health
effects
due
to
ozone
smog
even
if
the
TCEQ
leads
Houston
to
attainment
of
the
8­
hour
standard.

Response
GC8:
As
we
noted
in
the
final
Phase
1
Rule,
we
determined
in
the
1997
NAAQS
rulemaking
(
69
FR
23951)
that
we
did
not
need
to
retain
the
1­
hour
standard
to
protect
public
health.
Thus,
in
the
1997
NAAQS
rulemaking,
EPA
concluded
that
the
8­
hour
standard
would
replace
the
1­
hour
standard.
The
issue
of
whether
the
1­
hour
standard
is
needed
to
protect
public
health
has
not
been
reopened
here
and,
indeed,
should
be
considered
only
in
the
context
of
a
national
rulemaking
reviewing
the
NAAQS.

2.
Comments
on
the
Photochemical
Modeling
Comment
M1:
Commenter
(
Wilson)
comments
that
EPA
modeling
guidance
(
1996)
indicates
that
weight
of
evidence
analysis
included
to
supplement
the
deterministic
and
statistical
modeling
attainment
demonstrations
needs
to
be
compelling
to
overcome
the
results
from
the
photochemical
grid
model.
The
commenter
continues
to
cite
EPA
guidance
indicating
that
"
If
the
results
of
corroborative
analyses
are
also
consistent
with
the
conclusion
that
a
strategy
will
49
be
insufficient
to
meet
the
NAAQS
by
the
statutory
date,
attainment
would
not
be
demonstrated."
The
commenter
continues
that
the
SIP
revision
does
not
meet
EPA
guidance
for
demonstrating
attainment
because:
(
1)
The
plan
fails
the
deterministic
test
as
indicated
by
the
use
of
weight
of
evidence
(
WOE)
to
justify
dropping
the
August
31
from
the
modeling
episode.
(
2)
The
databases,
in
particular
emission
inventories,
used
in
the
modeling
have
a
number
of
problems
including
the
failure
of
TCEQ
to
reconcile
their
own
findings
about
the
under­
reporting
of
other
VOCs.
The
analysis
and
WOE
exhibit
a
selective
approach
to
the
examination
of
relevant
data
that
distorts
the
WOE
guidance
and
results
in
relaxation
of
WOE
requirements.
(
3)
The
episode
days
used
to
evaluate
the
control
strategy
do
not
include
days
with
observations
near,
but
slightly
above,
the
design
value
and
meteorological
ozone
forming
potential
likely
to
be
exceeded
about
once
per
year
as
advised
by
EPA
guidance.
(
4)
The
TCEQ's
corroborative
analyses
are
also
consistent
with
the
conclusion
that
the
strategy
is
insufficient
to
demonstrate
attainment.

The
commenter
summarizes
that
a
thorough
and
skeptical
consideration
of
TCEQ's
technical
analysis
must
result
in
the
EPA
finding
that
the
SIP
revision
does
not
demonstrate
attainment
of
the
1­
hour
ozone
standard.
The
commenter
continues
to
indicate:
(
1)
The
modeling
has
a
systematic
ozone
underprediction
bias
at
levels
above
120
ppb.
(
2)
TCEQ's
attainment
demonstration
has
failed
to
address
this
shortcoming
in
the
WOE
and
the
plan
does
not
include
control
measures
to
adequately
control
emissions
on
"
level
purple"
ozone
days
that
are
representative
of
the
region's
design
value.
(
3)
The
control
measures
included
in
the
plan
are
inadequate
to
meet
even
the
expectations
of
the
TCEQ.
The
commenter
then
indicates
that
EPA
should
not
approve
the
SIP
revision,
and
instead
find
that
TCEQ
has
failed
to
submit
a
50
plan
providing
for
implementation,
maintenance,
and
enforcement
of
the
ozone
NAAQS
for
the
HGB
area.

Response
M1:
As
also
discussed
in
other
responses,
EPA
did
not
dismiss
any
measures
or
analyses
used
by
TCEQ
for
their
model
performance
evaluation,
nor
did
EPA
disagree
with
TCEQ's
conclusion,
based
on
the
modeling
and
in
conjunction
with
the
WOE
analyses,
that
this
SIP
revision
should
result
in
the
HGB
area
attaining
the
1­
hour
ozone
standard
by
November
15,
2007.
EPA's
analysis
included
evaluating
model
performance
and
model
reaction
on
the
August
31st
episode
day
in
conjunction
with
the
additional
WOE
materials
that
TCEQ
provided
for
this
day,
as
well
as
the
rest
of
the
attainment
demonstration
period.
The
commenter
raised
a
number
of
specific
issues
that
are
addressed
in
this
comment
or
more
specifically
addressed
in
separate
comments,
but
the
combination
of
the
comments
do
not
sway
EPA's
technical
opinion
that
the
modeling
and
the
combined
Design
Value
(
DV)
approach
predicts
the
area
will
reach
attainment
by
the
end
of
2007.

EPA
also
reviewed
modeling
sensitivities
conducted
by
TCEQ
including
rough
adjustments
to
OVOCs,
but
concurred
with
TCEQ
that
the
body
of
supporting
material
to
conduct
a
refined
adjustment
for
OVOCs
did
not
currently
exist.
EPA
encourages
TCEQ
to
continue
to
research
this
issue
to
address
this
uncertainty
in
the
future
and
further
address
this
issue
in
the
8­
hour
ozone
SIP.
EPA
believes
that
most
of
the
error
can
be
best
explained
by
uncertainties
in
the
amount
of
HRVOC
that
were
actually
emitted
and
the
spatial
allocation
of
the
HRVOC
adjustment
and
meteorological
model
issues.
TCEQ
chose
an
average
value
for
the
adjustment
factor
for
the
HRVOCs
and
adjusted
the
same
level
over
the
entire
51
Houston/
Galveston/
Brazoria
area,
even
though
field
study
data
indicates
that
a
range
existed
that
was
many
times
higher
than
the
value
utilized
in
TCEQ's
modeling
in
some
cases.
The
TCEQ
and
EPA
agree
that
there
is
simply
not
enough
data
available
at
this
time
to
precisely
locate
all
of
the
sources
of
non­
inventoried
HRVOC
emissions.
The
TCEQ
is
pursuing
several
areas
of
research
that
will
use
additional
monitoring
data
and
other
data
to
improve
the
spatial
and
temporal
allocation
of
HRVOC
emissions,
and
is
simultaneously
pursuing
bottom­
up
methods
to
improve
emissions
inventories.
These
efforts
will
allow
a
much
more
refined
treatment
of
"
extra"
hydrocarbon
emissions
in
future
modeling.
TCEQ
should
continue
to
strive
to
yield
better
estimates
in
HRVOC
and
OVOC
emissions
from
industrial
facilities
in
HGB
and
this
should
continue
to
be
one
of
the
focus
areas
for
the
second
TEXAQS
study
in
2005­
2006.

EPA
agrees
that
TCEQ
made
an
appropriate
estimate
of
how
the
emission
inventory
for
HRVOCs
should
be
adjusted
without
sufficient
data
to
conduct
a
higher
level
of
adjustment
with
spatial
variability.
TCEQ
tried
to
gather
more
data
through
a
special
inventory
request
of
over
80
industrial
facilities
in
the
HGB
area,
but
was
not
able
to
collect
all
of
the
data
required
to
conduct
a
more
accurate
HRVOC
adjustment.
We
believe
our
understanding
of
the
process
is
sufficient,
however,
to
interpret
the
photochemical
model
results
and
determine
that
this
SIP
revision
is
approvable.

EPA
previously
reviewed
and
agreed
that
the
episode
(
8/
21­
9/
6/
2000)
was
appropriate
for
this
SIP
revision.
The
episode
did
include
several
days
(
8/
25,
8/
30,8/
31,
and
9/
5)
that
included
surface
level
monitored
data
greater
than
175
ppb
and
several
days
near
the
area's
design
value
at
the
time
of
the
episode
and
the
episode
did
have
the
benefit
of
intensive
data
collected
during
this
period.
Given
the
historical
difficulty
with
obtaining
acceptable
52
photochemical
model
performance
in
the
HGB
area,
EPA
recognizes
the
importance
of
selecting
days
from
a
field
study
period
in
preference
to
other
non­
field
study
days.
On
these
high
ozone
level
days
(>
175
ppb)
the
commenter
is
correct
that
the
model
had
an
under
prediction
bias
of
the
domain
peak
and
at
many
monitors
(
values
above
120
ppb).
But
this
is
thought
to
be
largely
the
result
of
many
issues
(
HRVOC
adjustments
and
the
two­
pronged
design
value
approach,
meteorological
issues,
general
modeling
issues,
etc.)
discussed
above
and
in
other
responses,
but
was
determined
acceptable
in
this
SIP
revision
due
to
the
inclusion
of
HRVOC
rules
that
will
remove
much
of
the
variability
in
HRVOC
emissions
and
result
in
significantly
lower
HRVOC
emission
levels.
It
should
also
be
noted
that
on
these
four
high
ozone
level
days
(
>
175
ppb
monitored),
EPA's
three
primary
ozone
statistic
metrics
were
within
EPA
guidance
parameter
for
all
four
days
(
including
the
August
31st)
with
the
exception
of
the
Peak
Prediction
accuracy
metric
on
the
August
30th
(
see
TSD
Tables
G.
1­
1
to
G.
1­
3
and
Texas
SIP
materials
for
details).

The
need
for
further
studies
does
not
mean,
however,
that
the
modeling
relied
upon
today
was
unable
to
estimate
the
amount
and
type
of
emission
reductions
needed
for
attainment.

EPA
believes
because
the
diagnostic/
sensitivity
tests
do
not
reveal
serious
flaws
in
model
formulations
and
the
model
generally
predicts
the
right
magnitude
of
the
peak
which
is
confirmed
by
the
statistical
measures
and
graphical
analysis,
that
the
model
does
provide
an
acceptable
tool
for
estimating
the
amount
of
emissions
reductions
needed.
It
is
EPA's
technical
opinion
that
based
on
the
modeling
and
the
weight­
of­
evidence,
the
State's
control
strategy
should
provide
for
attainment
by
November
15,
2007.
53
TCEQ
and
others
have
provided
significant
amounts
of
modeling
sensitivities,

monitoring
analyses,
etc.
as
part
of
the
corroborative
analyses
that
were
evaluated
in
the
decision
to
propose
approval
of
the
SIP
revisions.
While
some
components
of
the
corroborative
analysis
seem
to
indicate
that
the
SIP
revision
plan
may
not
succeed,
a
majority
of
the
components
indicate
that
the
plan
will
succeed.
EPA
has
weighed
many
different
analyses
from
TCEQ
and
others
(
including
the
HARC
H12
and
H13
project
results)
and
concluded
that
the
SIP
revision
plan
will
attain
by
the
attainment
date.
TCEQ
has
agreed
to
conduct
further
refinements
to
the
emission
inventory
and
meteorology
of
this
episode
in
development
of
the
8­

hour
ozone
SIP.
TCEQ
and
others
are
also
conducting
another
field
study
in
2005
and
2006.

TCEQ
has
indicated
that
they
will
attempt
to
weigh
any
new
information
derived
from
the
further
studies
and
evaluations,
and
incorporate
the
information
into
the
HGB
8­
hour
Ozone
SIP
to
be
submitted
to
EPA
by
June
15,
2007.

Comment
M2:
The
commenter
(
Wilson)
commented
that
they
are
concerned
with
final
episode
selection
and
with
the
modeling
results
for
that
episode.
The
commenter
continued
by
conjecturing
that
the
episode
included
in
the
modeling
does
not
contain
enough
days
with
observations
near,
but
slightly
above,
the
design
value
and
with
meteorological
ozone
forming
potential
that
is
likely
to
be
exceeded
about
once
per
year
as
is
advised
by
EPA
guidance.
The
commenter
also
indicated
that
the
SIP
revision
adequately
addresses
Air
Quality
Index
(
AQI)

level
"
Orange"
ozone
days
and
not
"
Purple"
level
ozone
days
when
the
HGB
area
has
a
AQI
level
"
Purple"
ozone
problem.

The
commenter
continued,
the
2003
design
value
for
the
1­
hour
ozone
standard
was
54
0.175
ppm
and
for
the
period
2000­
2003,
air
pollution
monitors
recorded
an
average
of
9
days
per
year
with
a
1­
hour
ozone
measurement
over
0.165
ppm,
and
about
1
additional
day
per
year
measured
over
0.205
ppm.
The
commenter
summarized
this
data
as
on
average
during
the
HGB
area
has
10
AQI
level
"
Red"
and
"
Purple"
days
per
year
during
the
2000­
2003
period.

The
commenter
also
indicated
that
according
to
ground­
level
monitoring
data
used
by
the
TCEQ
in
its
plan,
the
episode
used
for
control
strategy
evaluation
in
the
proposed
SIP
does
not
provide
ozone
formation
conditions
that
are
close
to
the
region's
design
value,
and
that
it
does
not
resemble
the
character
of
the
region's
serious
ozone
problems.
The
commenter
provided
a
graph
to
illustrate
that
the
plan's
best
effect
is
shown
by
reducing
several
AQI
level
"
Orange"
days
near
the
1­
hour
ozone
standard
of
0.12
ppm,
but
no
AQI
level
"
Red"
or
level
"
Purple"
days.
The
commenter
also
indicated
that
aircraft
data
and
Williams
tower
data
did
include
higher
AQI
levels
of
"
Red"
and
"
Purple"
in
some
of
the
areas
that
do
not
have
ground
monitoring
stations
with
the
caveat
that
some
of
this
data
was
of
shorter
duration
period.

The
commenter
continued
that:
"
The
TCEQ
estimates
the
effect
of
the
undocumented
emission
releases
by
calculating
an
alternative
design
value
of
144
ppb
for
comparison
to
the
actual
design
value
of
182
ppb
for
the
1999­
2001
period."
The
commenter
further
indicated
that
another
perspective
is
suggested
by
comparing
the
model
variability
in
peak
ozone
to
actual
variability
and
concludes
that
routine
variability
on
days
conducive
to
ozone
formation
is
limited
to
only
about
20
ppb,
compared
to
about
75
ppb
of
actual
variability
in
ozone
formation
observed
at
ground
monitors.
The
commenter
concludes
that
regardless
of
whether
one
concludes
that
38
ppb
(
182
ppb­
144
ppb)
or
55
ppb
(
75
ppb
­
20
ppb)
of
peak
ozone
formation
55
are
not
properly
modeled,
the
challenge
to
the
weight­
of­
evidence
analysis
is
clearly
substantial.

Response
M2:
The
original
episode
selection
of
August
19­
September
6,
2000
was
selected
by
TCEQ
with
EPA
review
and
comment
on
the
selection
of
the
episode.
This
TexAQS
2000
episode
was
selected
because
it
includes
a
19­
day
window
with
both
weekday
and
weekend
events,
a
suite
of
wind
directions,
and
daily
ozone
peaks
measured
in
several
different
areas
of
the
city
reflecting
the
net
surface
transport
during
each
day.
When
combined
with
the
additional
meteorological
and
precursor
data
collected
during
the
TexAQS
2000
study
period,
this
extended
ozone
episode
includes
a
better
than
normal
monitored
data
set
and
a
fairly
representative
mix
of
HGB
area
episode
types.
Given
the
historical
difficulty
with
obtaining
acceptable
photochemical
model
performance
in
the
HGB
area,
EPA
recognized
(
as
allowed
by
EPA
modeling
guidance)
the
importance
of
selecting
days
from
a
field
study
period
in
preference
to
other
non­
field
study
days
during
the
episode
selection
process
with
TCEQ.

EPA's
modeling
guidance
for
the
1­
hour
ozone
NAAQS
("
GUIDELINE
FOR
REGULATORY
APPLICATION
OF
THE
URBAN
AIRSHED
MODEL";
U.
S.
EPA;
July
1991;
pg.
11)

includes
the
following
text:

"
In
choosing
from
among
the
top­
ranked
episode
days,
consider
the
availability
and
quality
of
air
quality
and
meteorological
data
bases,
the
availability
of
supporting
regional
modeling
analyses,
the
number
of
monitors
recording
daily
maximum
ozone
concentrations
greater
than
0.12
ppm
(
i.
e.,
pervasiveness),
number
of
hours
for
which
ozone
in
excess
of
0.12
ppm
is
observed,
frequency
with
which
the
observed
meteorological
conditions
correspond
with
observed
exceedances,
and
model
performance
(
discussed
in
Chapter
5).
For
example,
the
top­
ranked
episode
day
within
56
a
meteorological
regime
may
have
only
routine
air
quality
and
meteorological
data
bases
available
for
use
in
the
modeling.
The
third­
highest
day,
however,
may
have
occurred
during
an
intensive
field
study,
so
that
a
more
comprehensive
data
base
is
available.

Thus,
the
third­
highest
day
may
be
more
desirable
for
modeling
than
the
top­
ranked
day."

As
EPA's
guidance
indicates,
days
with
not
quite
as
high
ozone
exceedances
may
be
chosen
over
the
highest
ozone
day
if
they
occurred
during
an
intensive
field
study.
Given
the
difficulties
and
uncertainties
with
modeling
the
Houston
area,
EPA
approved
the
selection
of
the
field
study
period
as
the
episode
period
to
be
modeled
in
accordance
with
EPA's
guidance.
It
should
be
noted
that
the
1­
hour
ozone
design
value
is
calculated
for
each
monitor
in
the
domain
and
is
the
4th
highest
1­
hour
ozone
value
in
a
three
year
period
(
see
EPA's
memo
titled
"
Ozone
and
Carbon
Monoxide
Design
Value
Calculations";
June
18,
1990).
Therefore
the
design
value
for
the
area
is
usually
lower
than
the
1st
high
value
as
the
commenter
indicated,
and
for
the
limited
time
period
(
2000­
2003)
that
the
commenter
analyzed,
the
HGB
area
design
value
was
not
a
"
Purple"
level
AQI
day,
but
a
mid
"
Red"
level
AQI
day.

Based
on
model
performance
issues,
the
original
episode
was
reduced
to
August
25,
26,

August
29
­
September
4,
and
September
6,
2000.
As
TCEQ
identified
in
their
response
to
comments,
it
is
important
to
note
that
six
1­
hour
ozone
exceedance
days
were
included
in
the
ten
day
modeling
period
(
August
25
­
September
1),
and
the
average
of
those
peaks
was
168.3
ppb.
This
modeled
period
of
the
episode
did
include
several
days
(
8/
25,
8/
30,8/
31,
and
9/
5)
that
included
surface
level
monitored
data
greater
than
175
ppb
and
several
days
near
the
area's
57
design
value
at
the
time
of
the
episode
and
the
episode
did
have
the
benefit
of
intensive
data
collection
that
occurred
during
this
period.
The
September
5th
day
was
dropped
due
to
model
performance
issues.
On
these
high
ozone
level
days
(>
175
ppb)
the
commenter
is
correct
that
the
model
had
an
under
prediction
bias
of
the
domain
peak
and
at
many
monitors
(
values
above
120
ppb),
but
this
is
thought
to
be
largely
the
result
of
many
issues
(
HRVOC
adjustments
and
the
two­
pronged
alternative
design
value
approach,
meteorological
issues,
general
modeling
issues,
etc.).
As
discussed
in
other
responses,
the
modeling
was
determined
to
have
an
acceptable
model
performance.
Even
with
an
under­
prediction
bias,
six
of
the
Base
5b
episode
days
had
values
greater
than
150
ppb
in
the
basecase
modeling
which
is
higher
than
the
Alternate
Design
Value
(
ADV)
of
144
ppb
that
TCEQ
used
(
and
7
days
above
144
ppb,
see
TSD
Table
H­
3)
.
In
evaluating
the
TSD
tables,
the
modeling
episode
included
three
monitored
"
Red"
AQI
level
days,
with
two
of
the
days
near
"
Purple"
levels
(
8/
25
and
8/
30).
With
the
combined
strategy
of
reducing
emission
events
and
routine
emissions,
EPA
would
not
expect
the
basecase
modeling
(
utilizing
a
routine
emission
approach)
to
include
ozone
levels
above
the
design
value.
Furthermore,
TCEQ
did
include
many
days
that
were
above
the
144
ppb
ADV
that
they
used
and
thus
we
weighted
this
fact
as
a
conservative
WOE
element.
We
also
concurred
with
the
selection
of
this
episode
and
that
it
included
enough
high
ozone
value
days
with
values
near
the
design
value
to
be
the
basis
for
attainment
demonstration
modeling.

Comment
M3:
Commenter
(
Wilson)
comments
that
the
episode
used
for
control
strategy
evaluation
in
the
proposed
SIP
does
not
provide
ozone
formation
conditions
that
are
close
to
the
region's
design
value,
and
do
not
resemble
the
character
of
the
region's
ozone
problems
with
the
under
prediction
of
the
peaks
and
the
modeled
peak
1­
hour
ozone
levels
only
varying
58
approximately
20
ppb
for
each
day
between
the
base
and
future
attainment
demonstration
modeling.
The
commenter
then
continues
that
TCEQ's
response
is
the
under
prediction
of
the
peaks
is
likely
due
to
unreported
or
under­
reported
releases
of
HRVOCs
and
that
EPA
concurred
in
this
assessment
of
the
model
performance
with
citations
from
EPA's
Technical
Support
Document.
The
commenter
continues
that
TCEQ
estimated
the
effects
of
undocumented
releases
by
estimating
an
Alternative
Design
Value
(
ADV)
of
144
ppb
compared
to
the
actual
design
value
of
182
ppb
for
the
1999­
2001
period.
The
commenter
then
discusses
an
alternate
approach
to
an
ADV
based
on
the
routine
variability
of
only
20
ppb
in
the
modeling.
The
commenter
summarizes
that
the
two
approaches
yield
either
a
38
ppb
or
a
55
ppb
level
of
peak
ozone
that
is
not
modeled
properly
and
that
the
challenge
to
the
WOE
is
substantial.

The
commenter
continued
that
EPA
properly
expressed
some
skepticism
that
underreported
short­
term
emission
releases
should
explain
the
entire
under­
prediction
of
peak
ozone
levels,
with
a
cite
from
EPA's
TSD.
The
commenter
concludes
that
EPA
should
further
conclude
that
several
other
factors
are
equally
likely
causes
of
the
under­
prediction
of
ozone
peaks
by
model
analysis:
failure
to
use
superfine
grid,
under­
reporting
of
OVOCs
(
both
routine
and
short­
term),
and
underestimation
of
emissions
from
ports
and
heavy
duty
diesel
trucks.
The
commenter
also
indicated
that
the
drop
in
ozone
design
values
over
the
last
several
years
is
due
to
the
implementation
of
NOx
RACT
and
favorable
meteorology.

Another
commenter
(
BCCAAG)
commented
in
favor
of
the
ADV
approach
and
the
ADV
value
of
144
ppb
as
utilized
by
TCEQ.
The
commenter
continued
that
the
strength
of
59
TCEQ's
WOE
demonstration
is
bourne
out
by
the
recent
decreases
in
ozone
values
(
Design
values,
#
of
days
of
exceedances,
#
of
1st
and
2nd
High
values)
in
HGB.
The
commenter
continues
that
this
occurred
despite
an
increase
in
ozone
monitors
and
economic
growth
in
the
region.

Response
M3:
As
previously
discussed
in
the
response
on
M2,
EPA
concurred
that
this
was
a
reasonable
episode
for
this
SIP
revision
and
that
it
included
enough
days
with
high
ozone
levels.

The
commenter
is
correct
in
indicating
that
for
most
days
the
modeled
change
between
base
and
2007
future
controlled
level
is
less
than
the
difference
between
the
daily
monitored
peak
and
124
ppb,
but
the
daily
difference
value
ranges
from
14.7­
37.6
ppb
with
an
average
of
approximately
27.5
ppb
(
not
20
ppb).
EPA
conducted
further
analysis
of
TSD
tables
G.
1­
2
and
G.
1­
3
in
preparing
response
to
this
comment.
The
original
episode
had
19
days
with
13
exceedance
days
with
an
average
of
1­
HR
daily
maximum
ozone
of
160
ppb
(
36
ppb
above
attainment)
and
a
range
of
exceedances
from
125
to
200
ppb
for
the
exceedance
days.
This
SIP
included
a
shorter
period
due
to
model
performance
issues
that
included
nine
exceedances
with
an
average
of
159
ppb
and
a
range
from
125
to
200
ppb
(
based
on
surface
measurements).

The
commenter
lists
a
number
of
issues­­
failure
to
use
superfine
grid,
under­
reporting
of
OVOCs
(
both
routine
and
short­
term);
and
underestimation
of
emissions
from
ports
and
heavy
duty
diesel
trucks
­­
that
may
be
part
of
the
reason
for
the
under­
prediction
bias
and
did
consider
these
issues
in
the
TSD
that
was
the
basis
for
our
proposal.
We
discuss
these
specific
issues
in
other
responses
in
this
notice,
but
we
believe
that
these
issues,
in
conjunction
with
other
issues
(
including
under/
unreported
emissions)
that
we
have
discussed
in
other
responses,
60
covers
most
of
the
issues
that
may
be
causing
the
under­
prediction
bias.
Specifically,
we
have
concluded
that
one
of
the
greatest
components
of
uncertainty
in
the
modeling
system
is
the
variability
and
under/
unreported
emissions
issue.
The
measures
included
in
this
revision
will
help
to
resolve
the
level
of
uncertainty
in
this
area.
As
noted
elsewhere
in
this
document,
we
have
reviewed
the
model
performance,
including
bias
issues,
and
have
determined
the
modeling
demonstration
to
be
acceptable.

Comment
M4:
Commenter
(
Wilson)
comments
that
the
TCEQ
should
have
developed
a
robust
method
of
relating
one­
and
five­
second
interval
ozone
data
collected
by
moving
aircraft
to
one
hour
ozone
estimates
measured
by
stationary
ground
monitors
so
that
airborne
monitoring
data
may
be
used
to
estimate
1­
hour
ozone
values
in
areas
of
the
HGB
area
that
are
far
from
ground
monitoring
stations.

Response
M4:
EPA
agrees
that
such
a
methodology
would
be
a
useful
analytical
tool
and
TCEQ
did
initiate
a
study
with
the
Pacific
Northwest
National
Laboratory
to
discuss
and
illustrate
problems
associated
with
comparing
observations
from
an
airborne
monitoring
platform
to
results
from
photochemical
model
grids
(
which
might
be
used
with
ground
based
monitoring
data).
Developing
such
a
methodology
is
a
complex
issue
since
the
methodology
must
take
into
account
temporal
differences
in
the
data
(
i.
e.
one
second
interval
for
airborne
data
versus
a
five
minute
interval
for
ground
data),
spatial
differences
in
the
monitors
(
differences
in
location
and
elevation),
and
environmental
differences
for
the
monitoring
equipment
(
temperature,
humidity,
solar
radiation,
etc.)
and
potentially
varying
levels
of
sensitivity/
accuracy
between
the
different
instruments
utilized.
61
Monitors
measure
concentration
at
a
point
in
space
and
in
reality,
these
concentrations
can
vary
significantly
over
a
grid
cell
or
an
area.
This
is
true
especially
for
ozone
if
it
is
contained
in
a
narrow
plume.
Inevitably,
a
grid
type
model
will
smooth
some
natural
phenomena
because
natural
conditions
are
averaged
over
the
volume
of
each
grid
cell.
For
instance,
model
output
represents
a
volume
average,
typically
4km
X
4km
by
50
meter
column.

As
a
result,
reasonable
comparisons
between
model
predictions
and
monitor
observations
are
not
expected
to
match
exactly.
With
reasonable
performance,
time
series
typically
show
similar
diurnal
cycles
but
not
exact
concentration
levels.
As
a
result,
it
is
very
difficult
to
obtain
a
precise
equality
between
modeled
concentration
and
monitored
concentration.
This
is
to
be
expected
and
does
not
necessarily
call
into
question
the
model's
utility
as
a
tool
to
predict
the
level
of
emission
reductions
needed
to
reach
attainment.
As
stated
in
previous
comments,
EPA
believes
the
model
provides
reasonable
predictions
of
ozone
levels
as
confirmed
by
comparisons
with
monitoring
data
and
therefore
can
provide
an
acceptable
estimate
of
the
amount
of
emissions
reductions
needed
for
attainment.

Comment
M5:
Commenter
(
Wilson)
commented
that
aircraft
data
were
excluded
from
the
model
performance
evaluation.
The
commenter
also
commented
that
the
TCEQ
should
have
revised
the
base
case
model
performance
evaluation
section
to
include
qualitative
evaluation
of
model
performance
based
on
aircraft
data,
including
reconsideration
of
alternative
model
approaches
that
may
appear
more
favorable
in
light
of
these
data.

The
commenter
then
indicated
that
TCEQ
had
performed
a
comparison
of
model
results
to
aircraft
data,
but
inadvertently
omitted
this
comparison
from
Appendix
B
of
TCEQ's
62
proposal.
Due
to
this
omission
during
TCEQ's
proposal,
the
commenter
indicates
that
they
have
reviewed
the
TCEQ's
analysis
and
are
providing
comments
on
TCEQ's
Appendix
B
analysis.

The
commenter
then
indicates
that
they
calculated
a
value
of
89
percent
as
the
difference
between
1­
hour
and
5­
minute
peaks
at
the
Deer
Park
Monitor
on
October
7,
1999
(
30
ppb
difference).
The
commenter's
analysis
then
utilized
this
89
percent
factor
to
scale
aircraft
data
to
1­
hour
ozone
values
for
comparisons
on
August
25­
30,
and
September
1,
3,
4,
and
6th.

The
commenter
then
continued
to
give
specific
analyses
of
aircraft
observations
to
model
predictions
for
each
of
these
days.
The
commenter
utilized
the
89
percent
factor
to
indicate
that
August
25,
30,
and
September
1st
were
days
that
aircraft
and
surface
monitoring
data
showed
levels
well
above
those
achieved
in
the
model.
The
commenter
also
utilized
the
89
percent
factor
to
indicate
that
aircraft
data
showed
ozone
levels
above
both
the
surface
monitoring
data
(
maximum
of
146
ppb)
and
model
performance
data
(
maximum
of
151
ppb)
for
August
29th.

The
commenter
also
utilized
the
89
percent
factor
to
conjecture
that
TCEQ
incorrectly
assessed
that
the
model
over­
predicted
ozone
formation
on
August
27
and
28
and
that
the
aircraft
data
suggests
that
the
model
does
accurately
predict
ozone
levels.
The
commenter
then
continued
on
that
the
model
under­
predicts
high
ozone
levels
above
120
ppb.

Response
M5:
TCEQ
did
include
the
Appendix
B
materials
in
the
SIP
submitted
to
EPA
and
63
EPA
reviewed
the
Appendix
B
as
part
of
the
review
conducted
for
the
proposal
notice.
Aircraft
observations
can
be
useful
in
assessing
model
performance,
but
must
be
done
with
care,
due
to
the
many
issues
outlined
in
Response
M4.
Due
to
these
technical
concerns
it
is
difficult
to
utilize
aircraft
data
other
than
in
a
qualitative/
directional
sense
for
comparing
aircraft
observational
data
to
4
km
hourly
grid
modeling
predictions.

The
commenter
did
not
provide
the
data
utilized
to
calculate
the
89
percent
conversion
value
to
convert
aircraft
data
into
an
estimate
of
1­
hour
ozone
concentrations.
The
commenter
did
indicate
that
this
value
was
calculated
using
only
one
day
of
data
at
one
monitor
in
the
HGB
area
for
a
day
that
is
not
during
the
modeled
episode
period
and
for
a
day
(
October
7,
1999)

that
is
not
even
during
the
main
period
of
ozone
season
in
the
HGB
area.
No
analysis
was
provided
to
document
that
this
was
a
typical
day,
or
a
typical
data
set
to
estimate
the
89
percent
conversion
factor
nor
was
an
effort
made
to
make
sure
the
data
sample
set
for
this
calculation
was
appropriate.
This
89
percent
value
seems
high
from
discussion
within
EPA
Region
6
including
monitoring
staff
that
typically
review
the
5­
minute
data
and
1­
hour
data.
Furthermore
the
commenter
has
made
several
assumptions
in
their
analysis
that
they
utilize
to
support
their
comment,
that
actually
weakens
their
analysis.
The
commenter
assumed
that
5­
minute
data
is
the
approximate
length
of
time
that
is
representative
of
the
aircraft
data
in
comparison
to
a
model
grid
square,
although
no
basis
was
given.
The
method
does
not
resolve
that
an
aircraft
would
be
a
line
sample
through
a
model
grid
square
at
an
altitude
that
does
not
have
hourly
monitored
data
and
would
not
be
the
same
sampling
as
a
single
monitor
(
if
you
could
have
one
at
the
altitude
of
the
aircraft).
The
commenter
did
not
adjust
for
a
model
that
calculates
a
large
volume
average
versus
an
aircraft
that
is
a
shorter
duration
line
sample
through
multiple
grid
64
cells
that
may
be
several
hundreds
of
meters
thick
for
the
layer
of
the
model
that
the
aircraft
would
be
flying.
Due
to
all
of
these
issues
including
the
very
limited
data
set
that
the
89
percent
was
generated,
we
have
to
discount
any
assessments
that
utilized
the
89
percent
factor.

While
the
commenter
is
correct
that
comparing
ground
observations
to
modeled
values,

the
model
does
under­
predict
ozone
concentrations
above
120
ppb
for
some
of
the
days.
As
discussed
in
response
to
comments
elsewhere
in
this
notice,
this
is
expected
and
was
fully
reviewed
and
determined
to
be
approvable
for
this
SIP
revision.

Comment
M6:
The
commenter
(
Wilson)
indicates
that
the
exclusion
of
one
kilometer
resolution
modeling
is
arbitrary
and
unreasonably
biases
the
results
in
favor
of
an
attainment
finding.
The
commenter
continues
by
disagreeing
with
EPA's
proposed
action
and
requests
that
EPA
evaluate
the
one
kilometer
resolution
modeling
as
useful
evidence
that
the
attainment
demonstration
is
insufficient.
The
commenter
argues
that
the
TCEQ
has
failed
to
present
a
compelling
technical
argument
for
excluding
one
kilometer
resolution
from
the
base
case
and
control
strategy
evaluations.
The
commenter
included
language
from
TCEQ
emails,
that
were
included
in
the
materials
that
were
reviewed
by
EPA
while
developing
the
proposal
and
TSD
for
this
action.
The
commenter
asserts
that
TCEQ
made
the
decision
to
exclude
one
kilometer
modeling
prior
to
attempting
to
develop
an
technical
justification
for
the
decision.
The
commenter
indicates
that
peak
ozone
levels
are
often
higher
for
one
kilometer
modeling,
but
other
model
performance
statistics
are
relatively
unchanged
when
the
one
kilometer
modeling
output
is
compared
to
the
four
kilometer
average
of
the
one
kilometer
resolution
output.
The
commenter
concluded
that
the
one
kilometer
resolution
modeling
made
attainment
65
demonstration
more
difficult
and
therefore
EPA
should
consider
that
statistics
do
not
degrade
and
the
peak
ozone
levels
are
better
represented
with
the
one
kilometer
modeling,
that
EPA
should
not
approve
the
demonstration
because
the
one
kilometer
grid
modeling
predicts
nonattainment
on
several
days
for
control
strategy
evaluations.

Response
M6:
While
the
commenter
asserts
that
EPA
should
reconsider
our
analysis
of
the
appropriateness
of
the
one
kilometer
resolution
modeling,
no
new
information
was
provided
that
was
not
previously
considered
in
our
review
during
the
development
of
the
proposal
and
TSD
for
this
action.
We
would
like
to
point
out
that
a
full
model
performance
analysis
(
including
statistics,
graphical
plots,
and
emissions
sensitivities)
were
not
provided
for
the
one
kilometer
resolution
modeling
by
the
commenter
or
in
the
TCEQ
SIP
revisions,
so
that
a
full
model
performance
analysis
could
be
compared
with
four
kilometer
model
performance
analysis.
Without
such
an
analysis,
it
is
difficult
to
ascertain
whether
one
kilometer
resolution
modeling
is
actually
better
performing
(
as
the
commenter
claims)
than
four
kilometer
resolution
modeling
or
just
yielding
higher
peak
ozone
values.

As
was
discussed
in
the
TSD,
concerns
have
been
raised
by
the
academic
community
that
while
the
CAMx
model
will
give
model
predictions
at
1km,
it
has
never
been
fully
evaluated
for
correct
performance
at
this
scale
in
the
HGB
area
and
that
the
uncertainties
associated
with
these
concerns
may
undermine
the
credibility
of
the
model
runs
upon
which
the
control
strategy
was
based.
Some
of
the
parameters
within
CAMx
which
raised
concerns
include
horizontal
and
vertical
diffusivities
and
assumptions
within
CAMx
that
apply
to
the
hydrostatic
equilibrium
of
horizontal
and
vertical
transport
may
begin
to
break
down
at
a
finer
grid
resolution.
66
TCEQ
indicated
in
their
response
to
comments
that
continued
evaluation
and
peer
review
of
these
uncertainties
is
necessary
before
the
model
can
routinely
be
applied
at
a
finer
resolution
to
replicate
all
conditions
of
ozone
formation.

For
further
discussion
of
technical
concerns
with
utilizing
the
one
kilometer
resolution
modeling
and
EPA's
thoughts
and
review
of
the
issue
please
see
the
proposal
and
TSD
for
this
action.

Comment
M7:
The
commenter
(
Wilson)
comments
that
while
short­
term
HRVOC
emission
events
are
surely
a
frequent
and
significant
cause
of
ozone
formation
in
the
Houston
area,
the
TCEQ
overstates
their
role.
The
commenter
continues
that
TCEQ
failed
to
consider
specific
problems
with
its
data,
and
then
TCEQ
made
broad
statements
that
are
not
supported
by
their
analysis.
The
commenter
then
indicates
that
a
more
rigorous
analysis
would
support
a
smaller,

yet
still
significant,
role
in
the
SIP.

The
commenter
then
commented
on
a
TCEQ
analysis
of
August
30
indicating
that
it
demonstrated
an
example
of
how
the
TCEQ
failed
to
identify
weaknesses
in
its
control
strategy
by
inconsistent
analysis.
The
commenter
stated
that
TCEQ
suggests
that
the
gap
between
the
modeled
peak
of
0.137
ppm
and
the
observed
peak
of
0.200
ppm
on
August
30
could
be
explained
by
the
evidence
that
one
or
more
emission
events
not
accurately
represented
in
the
modeling
inventory
occurred
on
this
day.
The
commenter
continued,
that
on
the
other
hand,
the
TCEQ
conducted
a
sensitivity
analysis
with
a
hypothetical
upset
included
on
August
30,
but
the
model
peak
only
increased
to
0.145
ppm.
The
commenter
further
indicated
that
TCEQ
67
minimized
the
importance
of
emission
events
on
ozone
formation
by
finding
that
"
emission
variability
of
roughly
1000
lb/
hr
should
be
expected
in
the
regions
upwind
of
peak,
region
wide
ozone
concentration
at
least
once
per
year
and
that
releases
over
approximately
a
two
to
three
hour
period
can
lead
to
increases
of
2­
3
ppb
in
peak
ozone
concentration
per
1000
lb
of
additional
HRVOC
emissions.
The
commenter
concluded
that
although
two
different
TCEQ
approaches
to
modeling
short­
term
emission
events
suggest
that
the
hypothesized
releases
of
August
30
could
be
expected
to
cause
4
ppb
to
9
ppb
of
additional
ozone,
the
TCEQ
appears
to
consider
this
an
acceptable
explanation
for
the
43
ppb
gap
between
the
model
and
measured
peak
ozone
levels.

The
commenter
also
indicated
that
TCEQ
failed
to
properly
analyze
the
impact
of
short­
term
events
on
ozone
formation
because
of
TCEQ's
failure
to
question
whether
the
inventory
of
emissions
caused
by
short­
term
releases
is
accurate
in
light
of
the
many
problems
with
emissions
inventories.
The
commenter
continues
that
self­
reported
upset
data
are
estimated
using
methods
that
have
been
called
into
question
for
many
sources,
including
flares,

cooling
towers,
storage
tanks
and
fugitive
leaks.
The
commenter
gives
the
example
that
flare
emissions
are
routinely
calculated
assuming
flare
performance
is
at
optimal
levels,
an
assumption
that
has
been
questioned
by
the
TCEQ
in
its
technical
analysis
(
e.
g.,
the
"
big
smoky"

August
30th
flaring
event)
and
by
the
EPA.

The
commenter
then
criticizes
TCEQ
for
TCEQ's
remarks
on
an
absence
of
evidence
available
at
this
time
to
warrant
a
correction
factor
for
under­
reported
upset
emissions
and
as
a
result,
TCEQ
decided
to
not
conduct
a
speculative
sensitivity
analysis.
The
commenter
68
continued
that
on
the
other
hand
TCEQ
indicated
that
unreported/
underreporting
of
short
term
releases
of
HRVOCs
is
responsible
for
the
underprediction
bias
in
the
modeling
on
some
days.

The
commenter
concludes
that
TCEQ's
failure
to
assess
the
accuracy
of
the
upset
inventory
causes
EPA
to
speculate
on
the
implications
of
this
omission
and
exactly
how
much
of
the
underprediction
bias
is
due
to
unreported/
underreported
emission
events.

Response
M7:
As
we
discussed
in
our
proposal
and
TSD,
the
attainment
strategy
is
based
on
a
two­
pronged
approach:
control
of
routine
emissions
and
a
short­
term
limit
to
control
emission
events.
The
TCEQ
indicated
that
the
influence
from
short­
term
releases
must
be
removed
from
the
area's
design
value
to
determine
the
design
value
based
on
routine
emissions.
This
alternative
design
value
theoretically
will
more
closely
correspond
to
the
routine
urban
ozone
formation
captured
by
the
model.
To
remove
influence
of
short­
term
releases,
TCEQ
applied
Blanchard's
technique
on
the
1999­
2001
AIRS
data.
This
technique
uses
a
threshold
of
a
40
ppb
rise
in
ozone
concentration
in
one
hour
to
distinguish
sudden
rises
from
the
more
typical
case
where
ozone
increases
more
gradually.
Removing
all
days
with
identified
sudden
ozone
concentration
increases
(
SOCI),
an
alternate
design
value
of
144
ppb
was
calculated
by
TCEQ.

Final
base
case
(
i.
e.,
Base
5b)
includes
seven
days
with
modeled
peak
ozone
greater
than
144
ppb,
so
the
modeled
peaks
in
fact,
represent
very
well
the
TCEQ
estimated
(
non­
SOCI)
design
value.

EPA
considers
the
alternative
design
value
approach
a
reasonable
tool
in
evaluating
the
possible
impact
of
non­
routine
emission
releases,
particularly
releases
of
HRVOCs
on
the
design
69
value.
By
removing
the
days
that
have
rapid
ozone
formation
and
therefore
are
possibly
the
result
of
large
releases,
it
is
possible
to
get
a
sense
of
the
impact
of
emission
releases
on
the
design
value.
We
are
not
convinced
that
all
occasions
where
ozone
rises
by
40
ppb
from
one
hour
to
the
next
are
caused
by
releases.
Some
of
these
events
could
be
caused
by
continuous
plumes
of
ozone
sweeping
across
a
monitor
as
winds
shift
direction.
These
issues
take
some
of
the
benefit
away.
In
addition,
other
studies
(
including
H13)
of
the
frequency
of
reported
emission
events
have
indicated
that
the
occurrence
of
reported
events
in
the
right
location
at
the
right
time
in
order
to
impact
peak
ozone
levels
only
occurs
with
a
small
percentage
of
non­
routine
releases.
Still,
we
agree
that
emission
events
do
impact
the
design
value
to
some
degree.
Therefore,
we
agree
that
considering
the
alternative
non­
SOCI
design
value
provides
additional
evidence
that
the
future
design
value
will
reach
the
standard
in
the
future
case.

We
disagree
with
the
commenter's
criticism
of
TCEQ's
analysis
of
August
30th.
The
30th
had
a
large
flaring
event
that
was
likely
underestimated
even
with
the
hypothetical
run
by
TCEQ
as
the
photographs
indicate
the
flare
was
not
completely
combusting
the
emissions.

TCEQ
considered
a
hypothetical
situation
and
was
conservative
(
both
TCEQ
and
EPA's
TSD
include
this
evaluation)
in
estimating
the
true
level
of
emissions
present.
TCEQ's
analysis
does
indicate
that
their
hypothetical
event
would
impact
the
ozone
levels
significantly
and
if
actual
emissions
data
were
available
to
model,
it
would
likely
show
a
much
larger
impact.
TCEQ's
analysis
was
to
support
that
at
a
minimum,
the
"
big
smoky"
flare
event
could
have
a
significant
impact
on
the
30th
and
other
such
events
would
yield
similar
results.
Furthermore,
the
flare
sensitivity
does
not
have
to
explain
all
of
the
underprediction
bias
on
the
30th
as
many
other
factors
(
meteorology,
emissions
from
other
sources,
etc.)
also
can
result
in
such
a
bias.
70
Furthermore,
without
the
additional
monitoring
of
units
in
HRVOC
service
that
is
included
in
this
SIP
revision,
it
is
impossible
to
determine
the
absolute
accuracy
of
HRVOC
emission
estimates
from
flares
and
similar
emission
sources.
Therefore
neither
TCEQ
nor
EPA,

could
completely
assess
the
full
extent
to
which
that
HRVOC
emission
events
impact
daily
ozone
levels.
TCEQ
has
required
monitoring
and
restriction
of
HRVOC
emissions
that
will
reduce
the
chance
of
these
types
of
emissions
impacting
ozone
exceedances
levels.

As
we
indicated
in
the
TSD
for
this
notice,
other
studies
(
including
H13)
of
the
frequency
of
reported
emission
events
have
indicated
that
the
occurrence
of
reported
events
in
the
right
location
at
the
right
time
in
order
to
impact
peak
ozone
only
occurs
with
a
small
percentage
of
non­
routine
releases.
The
H13
study
relied
on
reported
emission
events
that
are
likely
underreported
and
also
should
be
considered
a
conservative
estimate
of
potential
impacts
from
short­
term
HRVOC
emission
events
since
some
events
are
larger
than
the
levels
modeled
and
ozone
formation
is
not
linear.
TCEQ
determined,
and
EPA
concurs,
that
it
is
necessary
to
reduce
the
frequency
of
emission
events
so
that
emission
events
do
not
interfere
with
attainment
of
the
1­
hour
NAAQS,
which
only
allows
an
average
of
one
exceedance
per
year.
Based
on
our
review,
we
believe
the
hourly
emission
limit
will
achieve
this
goal.
Because
facilities
would
be
expected
to
take
action
to
avoid
emissions
events
exceeding
the
short­
term
limit
of
1,200
lbs/
hr,

we
anticipate
that
the
frequency
of
such
events
in
the
future
will
be
lower
than
in
the
past
and
therefore
less
than
one
event
per
year
impacting
peak
ozone
should
be
expected.
Even
though
emission
levels
above
1,200
lbs/
hr
do
not
count
towards
the
Annual
Cap,
the
Annual
Cap
level
is
low
enough
that
a
source
could
not
operate
at
a
1,200
lb/
hr
rate
for
extended
periods
without
severely
impacting
its
Annual
cap
level
that
is
on
the
order
of
2,000
lbs/
day
or
less
for
most
71
facilities
(
maximum
cap
is
2,419
lbs/
day).
For
more
details
about
the
relationship
of
the
shortterm
limit
and
annual
cap,
please
see
the
response
for
comment
M8,
the
proposal
and
TSD
materials.

The
commenter
criticizes
TCEQ
for
not
estimating
the
level
of
under
reporting
and
unreported
emissions,
but
without
flow
monitors
and
other
monitoring
requirements
on
HRVOC
emissions
(
that
are
being
approved
as
part
of
this
revision),
it
would
be
pure
speculation
by
TCEQ
without
any
strong
basis.

Comment
M8:
The
commenter
(
Wilson)
comments
that
TCEQ
inappropriately
assumed
that
upset
emissions
will
not
occur
in
the
future.
The
commenter
continues
that
TCEQ
should
have
considered
the
chance
for
upset
emission
events
to
occur
in
the
future
in
its
weight­
of­
evidence
analysis.

Response
M8:
While
the
structure
of
the
HECT
and
the
HRVOC
rules
anticipates
that
emission
events
will
not
be
completely
eradicated,
EPA
believes
that
in
combination
these
programs
provide
sufficient
disincentives
that
sources
will
reduce
the
frequency
and
magnitude
of
large
emissions
events
such
that
emission
events
would
not
be
expected
to
impact
peak
ozone
levels.
The
University
of
Texas
report
"
Variable
Industrial
VOC
Emissions
and
Their
Impact
on
Ozone
Formation
in
the
Houston
Galveston
Area,"
April
16,
2004,
estimated
from
historic
information
that
it
is
probable
that
at
least
one
event
will
occur
annually
at
a
time
and
location
to
impact
peak
ozone.
It
is
therefore
necessary
to
reduce
the
frequency
of
emission
72
events
so
that
emission
events
do
not
interfere
with
attainment
of
the
1­
hour
NAAQS,
which
only
allows
an
average
of
one
exceedance
per
year.
Based
on
this
study,
we
believe
the
hourly
emission
limit
will
achieve
this
goal.
Because
facilities
would
be
expected
to
take
action
to
avoid
non­
routine
emissions
events
exceeding
the
short­
term
limit
of
1,200
lbs/
hr,
we
anticipate
that
the
frequency
of
such
events
in
the
future
will
be
lower
than
in
the
past
and
therefore
less
than
one
event
per
year
impacting
peak
ozone
should
be
expected.

Based
on
the
final
HECT
allocation
scheme
updated
March
20,
2006,
the
largest
allocation
is
441.9
tons.
This
allocation
is
approximately
equivalent
to
100.9
lb/
hr,
assuming
the
facility
will
operate
with
the
allocation
as
an
hourly
average
to
represent
routine
emissions.

Therefore,
the
largest
HECT
allocation
will
be
approximately
twelve
times
smaller
than
the
1200
lb/
hr
short­
term
limit.
For
every
other
source
under
the
HECT,
the
disparity
would
be
even
greater.
Based
on
this
difference
between
the
short­
term
limit
and
presumed
routine
emissions
levels,
no
source
would
be
able
to
operate
at
the
hourly
limit
for
an
extended
period
of
time
without
pushing
its
emissions
total
close
to
or
above
the
annual
cap.
Therefore,
as
discussed
in
our
proposal,
only
truly
non­
routine
emissions
are
expected
to
exceed
the
hourly
limit.
Furthermore,
all
exceedances
of
the
1200
lb/
hr
limit
are
subject
to
enforcement,
which
should
act
as
a
further
deterrent
to
excess
emissions
events.

Comment
M9:
The
commenter
(
Wilson)
commented
that
EPA
should
not
approve
the
TCEQ's
approach
to
less
reactive
VOCs,
but
should
assume
that
the
failure
to
analyze
and
develop
control
strategies
for
Other
VOCs
(
non­
highly
reactive
volatile
organic
compounds)
will
lead
to
higher
levels
of
ozone
formation
than
is
represented
by
the
TCEQ
modeling
analysis.
The
73
commenter
continues
that
there
is
evidence
that
Other
VOCs
(
OVOCs)
are
underestimated
in
the
inventory
and
are
a
source
of
uncertainty.
The
commenter
cites
to
a
study
by
Environ
"
Top
Down
Evaluation
of
the
Houston
Emissions
Inventory
Using
Inverse
Modeling"
(
Yarwood
et
al.,
2003)
which
indicated
that
about
the
right
amount
of
reactivity
had
been
added
to
the
model
and
that
further
adjustment
is
not
warranted.
The
commenter
reiterated
EPA's
TSD
by
stating
that
the
report
indicates
that
about
the
right
amount
of
reactivity
had
been
added
to
the
model
by
TCEQ
with
scaling
of
olefin
to
NOx
emissions
and
that
further
adjustment
to
the
inventory
is
not
warranted.
The
commenter
indicates
that
the
Yarwood
study
is
not
conclusive
on
the
point
of
assuming
a
linear
function
of
emissions
from
each
of
the
source
categories
and
further
cites
from
the
study
"
this
finding
does
not
rule
out
the
possibility
of
achieving
more
significant
improvements
in
model
performance
if
just
the
right
combination
of
relatively
large
adjustments
were
applied
to
the
inventory."
The
commenter
continues
by
further
citing
from
the
Yarwood
report
and
indicates
that
statistically
significant
improvements
in
model
performance
were
seen
by
increasing
VOCs
from
area
and
mobile
sources
near
and
inside
Beltway
8,
and
point
sources
located
in
the
west
end
of
the
Houston
Ship
Channel.
The
commenter
also
indicated
that
the
report
indicated
that
the
underestimation
of
VOCs
in
the
Ship
Chanel
sub­
region
is
particularly
severe.
The
commenter
concluded
that
TCEQ
did
not
conduct
a
balanced
evaluation
of
the
Yarwood
study
and
its
OVOC
modeling
effort
when
TCEQ
adopted
the
SIP
revision.

The
commenter
indicated
that
TCEQ's
one
base
case
modeling
sensitivity
with
an
adjusted
OVOC
inventory
improved
model
performance
including
the
performance
of
the
peak
predicted
value.
74
The
commenter
indicates
that
the
case
for
adjusting
OVOC
emissions
is
also
supported
when
evaluating
the
composition
of
model
cell
box
in
Channelview
area
to
the
long­
term
Auto
Gas
Chromatograph
(
GC)
data
from
Channelview
and
Deer
Park
monitors.
The
commenter
continues
that
the
Ethylene
and
Olefin
portions
are
a
larger
percent
of
total
VOC
compared
to
the
monitoring
data.
The
commenter
also
indicates
that
the
OVOCs
portions
are
under
estimated
by
the
box
model
compared
to
the
long­
term
monitoring
data.

The
commenter
also
presented
information
on
TCEQ's
future
year
modeling
sensitivity
with
the
OVOCs
imputed
and
then
compared
future
year
peak
values
with
the
CS06a
run
and
a
control
of
all
VOCs
run
(
these
runs
were
in
TCEQ's
TSD).
The
commenter
comments
that
the
imputing
of
OVOCs
raises
peak
ozone
values
2­
30
ppb
for
the
days
of
the
episode.

Response
M9:
The
TCEQ
was
reluctant
to
make
any
inventory
adjustments
which
could
be
viewed
as
arbitrary
for
modeling
purposes.
Even
though
there
exists
some
data
that
OVOCs
may
be
under
reported,
TCEQ
decided
that
they
did
not
have
sufficient
data
to
justify
a
particular
emission
inventory
adjustment
to
OVOCs.
EPA
has
also
commented
in
the
past
that
TCEQ
should
investigate
OVOC
adjustments
and
in
our
TSD
and
proposal
we
indicated
that
OVOC
underreporting
concern
is
an
issue
of
uncertainty.
At
this
time
though,
we
recognize
that
TCEQ
did
not
think
they
had
enough
data
to
develop
a
control
strategy
including
a
inventory
that
had
imputed
OVOCs.
We
agree
with
the
commenter
that
the
Yarwood
report
has
some
interesting
sensitivities
and
potential
impacts,
but
the
body
of
data
to
support
an
OVOC
adjusted
inventory
was
not
present
when
TCEQ
developed
the
SIP
in
2004.
While
the
peak
modeling
values
increased
in
the
basecase
with
the
imputed
OVOCs,
a
full
model
75
performance
analysis
including
statistics,
time
series,
graphical,
and
responses
to
variations
in
EIs
inputs
was
not
done,
so
EPA
does
not
conclude
that
overall
model
performance
was
better
with
the
imputed
OVOCs.
A
full
modeling
analysis
would
need
to
be
conducted
with
the
items
listed
to
determine
if
the
imputed
OVOCs
was
getting
the
right
answer
for
the
right
reason.

TCEQ
conducted
model
performance
analysis
of
this
level
with
both
the
base
inventory
and
then
with
the
HRVOC
imputed
inventory
in
order
to
support
that
the
HRVOC
imputed
inventory
was
actually
an
improvement
in
the
modeling.
We
will
continue
to
encourage
TCEQ
to
investigate
OVOCs
in
the
development
of
their
future
HGB
SIPs.
A
separate
study
by
Yarwood
(
H6E.
2002
report)
cited
in
our
TSD
included
analysis
showing
that
the
Olefin
to
NOx
imputing
factor
that
TCEQ
utilized
produces
approximately
the
correct
amount
of
reactivity
in
the
model.
The
olefin­
to­
NOx
adjustment
was
applied
only
after
a
large
body
of
peer
reviewed
research
showed
conclusively
that
such
a
discrepancy
affected
emissions
of
certain
HRVOCs
from
industrial
sources.
The
bibliography
included
in
TCEQ's
TSD
includes
a
list
of
many
of
the
peer
reviewed
studies
considered
by
TCEQ
and
reviewed
by
EPA.

In
TCEQ's
response
to
comments
on
their
HGB
proposal
in
June
2004
they
agreed
that
there
is
some
evidence
that
OVOCs
may
be
underestimated
in
the
modeling
inventory,
but
the
evidence
to
justify
adjusting
emissions
of
OVOC
is
much
less
conclusive
and
open
to
debate.

TCEQ's
response
continued,
that
at
that
time,
few
in­
depth
analyses
of
aircraft
observations
had
been
conducted
comparing
OVOC
concentrations
with
those
expected
based
on
the
reported
emissions.
The
TCEQ
compared
ambient
concentrations
of
OVOC
with
the
reported
inventories
at
the
Clinton
Drive
and
Deer
Park
monitoring
locations
and
used
this
data
to
conduct
the
OVOC
modeling
sensitivity.
The
study
suggested
that
OVOC
may
be
76
underreported
by
a
factor
of
4.8.
The
scope
of
this
study
was
limited
however,
because
in
2004
only
these
two
TCEQ
sites
had
collected
continuous,
multi­
year
speciated
hydrocarbon
data
in
the
Ship
Channel
industrial
district.
We
encourage
TCEQ
to
continue
to
evaluate
the
Auto
GC
data
and
utilize
the
data
in
developing
future
SIPs.

Based
on
our
comments
above
on
the
need
for
a
full
base
case
model
performance
to
justify
the
OVOC
adjustment
as
an
improvement
in
the
modeling,
we
do
not
concur
with
commenter's
comment
that
the
future
year
model
predictions
with
additional
OVOCs
included
are
of
enough
concern
that
EPA
should
not
approve
these
SIP
revisions.
The
future
year
sensitivity
modeling
is
speculative
and
the
base
modeling
was
not
verified
to
actually
be
a
better
performing
modeling
system
with
the
OVOC
imputation.

In
TCEQ's
response
to
comments
on
their
June
2004
proposal,
they
indicated
that
if
the
OVOC
emissions
are
indeed
underestimated
substantially,
then
additional
reductions
may
be
necessary.
We
encourage
TCEQ
to
continue
to
evaluate
OVOCs
in
their
development
of
the
8­

hour
SIP
for
HGB.

Comment
M10:
The
commenter
(
Wilson)
commented
that
the
8­
hour
ozone
non­
interference
demonstration
is
inadequate
and
biased,
and
that
furthermore,
may
be
based
on
a
faulty
emissions
inventory
since
OVOCs
were
not
adjusted
and
errors
in
simulating
the
CS­
2001
control
strategy
occurred.
The
commenter
concludes
that
EPA
must
find
that
the
noninterference
demonstration
is
inadequate
and
disapprove
the
relaxation
of
control
measures
that
if
kept,
could
contribute
to
progress
towards
attaining
the
8­
hour
standard.
77
The
commenter
continues
that
the
8­
hour
modeling
results
presented
in
TCEQ's
TSD
shows
that
the
proposed
1­
hour
strategy
falls
short
of
making
reasonable
progress
towards
8­

hour
attainment.
The
commenter
continues
that
the
plan
backslides
in
comparison
to
the
2001
approved
plan
because
six
of
the
16
monitors
show
higher
8­
hour
Design
Values
and
the
area
of
exceedances
is
larger
on
6
of
the
10
days
with
the
new
SIP
revisions.
The
commenter
also
comments
the
average
of
the
relative
reduction
factors
is
essentially
unchanged
(
0.7
percent
lower
after
implementation
of
the
proposed
control
strategy
as
compared
to
the
EPA­
approved
control
strategy)
and
that
significant
additional
reductions
will
be
necessary
to
attain
the
8­
hour
ozone
standard.

The
commenter
indicated
that
in
addition
to
excluding
the
analysis
of
adjustments
to
the
OVOC
inventory,
the
TCEQ
made
a
number
of
other
assumptions
that
tend
to
bias
the
noninterference
demonstration
in
favor
of
the
proposed
control
strategy.

The
commenter
indicated
that
the
use
of
updated
activity
data
as
the
basis
for
the
CS­

2001
may
add
as
much
as
20
tpd
more
NOx
than
would
be
allowed
by
the
SIP
revision
that
EPA
is
proposing
to
approve.
The
commenter
did
recognize
that
TCEQ
had
made
several
technical
updates
by
using
Mobile
6
that
were
acceptable.
The
commenter
commented
that
a
13
percent
increase
in
VMT
that
was
included
for
the
2000
motor
vehicle
emissions
budget
(
MVEB)
should
have
been
restricted
to
the
old
VMT
and
that
the
inclusion
of
the
additional
VMT
is
inappropriate.
The
commenter
continued
that
they
were
concerned
with
the
use
of
a
revised/
updated
2007
Traffic
Demand
Model
as
the
basis
for
the
CS­
2001
inventory
because
this
included
the
new
activity
data,
which
results
in
as
much
as
20
tpd.
The
commenter
78
continued
that
the
old
activity
data
should
be
used
unless
EPA
approves
a
new
MVEB.

The
commenter
indicated
that
if
EPA
approves
the
use
of
updated
activity
data
for
the
baseline
model,
then
the
MVEB
is
not
a
binding
constraint
.
The
commenter
urged
EPA
to
reconsider
our
guidance
on
the
noninterference
test
and
conduct
our
own
analysis
in
a
manner
consistent
with
their
comments.

Response
M10:
EPA
disagrees
with
the
assertion
that
the
non­
interference
demonstration
is
inadequate
and
biased,
and
that
it
represents
backsliding.
As
indicated
in
more
detail
in
the
proposal
notice
and
TSD
for
this
action,
it
was
our
observation
that
while
individual
monitors
may
have
increases
in
ozone,
overall
the
modeling
metrics
indicated
either
an
even
benefit
or
a
slight
increased
benefit
for
the
8­
hour
ozone
NAAQS.
EPA
gave
the
State
guidance
that
noninterference
and
equivalence
can
be
demonstrated
by
showing
through
an
air
quality
analysis,

that
the
new
strategy
will
not
create
more
8­
hour
ozone
exceedances,
higher
8­
hour
ozone
concentrations,
or
higher
cumulative
exposure
levels
than
the
old
strategy.

The
8­
hour
demonstration
process
uses
the
model
in
a
relative
sense
using
Relative
Reduction
Factors
(
RRFs),
so
8­
hour
modeling
may
show
attainment
with
RRF
analysis
but
still
have
grid
cells
over
the
standard
in
the
model
predictions.
The
results
indicated
that
CS­
08
is
slightly
more
effective
in
reducing
8­
hour
ozone
levels
than
CS­
2001
in
both
average
relative
reduction
factor
(
0.931
vs.
0.940)
and
in
future
design
value
(
107
v.
s.
108
ppb),
even
though
some
stations
fare
slightly
worse
under
the
new
control
strategy
as
the
commenter
indicated.
In
weighting
the
110(
l)
analysis,
the
closest
thing
to
the
attainment
test
is
the
change
in
RRFs
and
79
the
change
in
Future
design
values
between
the
old
and
new
strategies.
This
is
the
brightest
line
test,
so
a
reduction
in
these
is
a
good
indicator
of
non­
interference.
For
most
of
the
design
values,
they
decrease
with
the
new
strategy
(
See
Table
I­
3
on
page
76
of
EPA's
TSD).
It
is
also
important
to
realize
that
all
of
the
higher
design
values
(>
95
ppb)
decrease
with
the
new
strategy
and
with
the
exception
of
the
Bayland
Park
(
BAYP)
monitor
(
which
dropped
1
ppb),

they
dropped
a
significant
value
(
5­
8
ppb).

In
addition,
for
both
peak
8­
hour
ozone
concentration
and
exposure
metrics,
benefits
of
the
new
strategy
exceed
those
of
the
old
strategy
for
every
day
that
was
modeled
except
September
6,

where
the
old
strategy
performs
slightly
better.
For
the
area
of
exceedance
however,
the
comparison
is
less
clear­
cut.
As
the
commenter
indicated
for
area
of
exceedance,
the
older
strategy
shows
more
of
a
benefit
on
six
of
ten
days
and
the
new
strategy
shows
a
greater
benefit
on
three
days
and
on
one
day
both
strategies
are
equivalent.
Even
though
more
grid
cell
area
per
day
were
predicted
to
be
in
nonattainment,
when
the
level
of
ozone
above
nonattainment
was
weighted
with
the
grid
cells
predicted
to
be
in
nonattainment,
the
ozone
exposure
metric
showed
improvement
for
the
majority
of
the
days.
EPA's
guidance
for
demonstrating
attainment
for
the
8­
hour
ozone
NAAQS
is
to
use
the
RRFs
average
for
all
the
days
that
monitors
had
elevated
ozone.
So
even
though
some
days
had
larger
exceedance
areas,
the
ability
to
attain
the
8­
hour
ozone
NAAQS
will
be
more
heavily
weighted
by
the
change
in
the
average
RRFs
and
the
monitors
with
the
higher
design
values.
Although
there
are
uncertainties
with
comparing
the
modeled
results
of
the
two
strategies,
EPA
believes
that
the
new
strategy
and
the
old
strategy
are
at
least
equivalent
in
overall
8­
hour
ozone
benefit
with
the
new
strategy
slightly
more
effective
in
reducing
the
peak
ozone
values
and
the
old
strategy
slightly
more
80
effective
in
reducing
the
area
of
exceedance.
In
summary,
both
the
Future
design
values
and
RRFs
are
lower
for
the
new
strategy
(
especially
for
the
higher
design
values
that
will
be
critical
in
future
8­
hour
attainment
SIP
development).
Furthermore,
two
of
the
three
ozone
metrics
showed
improvement
with
the
new
strategy.
Taking
all
of
these
metrics
into
consideration
and
recognizing
the
uncertainties
in
the
modeling,
we
believe
that
Texas
has
demonstrated
that
the
new
strategy
will
not
interfere
with
attainment
of
the
8­
hour
standard.

The
EPA
agrees
that
a
different
mix
of
control
measures
may
be
necessary
to
reach
attainment
of
the
8­
hour
ozone
standard
and
the
State
will
need
to
address
this
in
their
8­
hour
ozone
attainment
SIP
that
is
due
in
June
2007.
At
that
same
time,
the
State
will
need
to
submit
its
"
reasonable
progress"
SIP
for
the
8­
hour
standard.
As
discussed
previously
in
the
response
to
comment
for
M9
comment,
EPA
determined
that
the
Emission
Inventory
utilized
for
this
attainment
demonstration
modeling
was
acceptable.
EPA
ultimately
agreed
with
TCEQ
that
there
was
not
enough
data
and
studies
on
OVOCs
to
warrant
imputing
the
inventory
for
OVOCs.
Therefore,
it
would
not
have
been
reasonable
to
make
a
OVOC
adjustment
in
the
110(
l)
analysis.

TCEQ
discussed
with
EPA
the
best
approach
to
making
this
demonstration.
One
of
the
key
issues
of
concern
in
conducting
it
was
the
fact
that
the
photochemical
modeling
is
now
based
on
an
improved
August­
September
2000
ozone
episode
rather
than
the
older
September
1993
ozone
episode
on
which
the
December
2000
SIP
was
based.
Recognizing
that
this
was
a
major
change
since
2000,
the
noninterference
modeling
included
the
control
strategies
listed
in
the
December
2000
SIP
together
with
updated
inventories
and
updated
methodologies
utilizing
81
the
2000
episode.

The
commenter
emphasized
that
the
December
2000
SIP
MVEB
placed
a
"
binding
constraint"
on
how
any
CS­
2000
onroad
inventory
should
be
developed.
It
was
also
suggested
that
the
CS­
2000
inventory
should
have
coupled
updated
MOBILE6­
based
emission
rates
with
the
old
VMT
and
other
associated
activity
data
from
the
December
2000
MVEB.
This
suggestion
is
impractical
because
an
onroad
emissions
inventory
which
becomes
an
MVEB
is
a
combination
of
both
emission
rates
(
from
the
MOBILE
emissions
model)
and
activity
data
(
from
a
travel
demand
model).
EPA
concurs
with
the
method
that
TCEQ
conducted
the
VMT
and
MVEB
for
this
110(
l)
analysis.

The
2007
on­
road
inventory
that
was
developed
for
the
December
2000
SIP
included
an
estimate
of
129.4
million
VMT
from
the
Houston
Galveston
Area
Council's
(
HGAC)
travel
demand
modeling.
Since
that
time,
new
travel
networks,
demographic
data,
census
data,
etc.

inputs
have
been
added
to
HGAC's
travel
demand
modeling
process,
and
the
updated
2007
onroad
inventory
was
developed,
146
million
VMT
is
the
best
available
estimate
of
2007
activity
levels.
This
inventory
was
developed
by
following
EPA's
memo
entitled
"
Policy
Guidance
on
the
Use
of
MOBILE6
for
SIP
Development
and
Transportation
Conformity",
dated
January
18,

2002,
which
can
be
found
at
http://
www.
epa.
gov/
otaq/
m6.
htm.

The
test
that
EPA
has
to
apply
to
this
SIP
revision
is
that
the
revisions
demonstrate
attainment
with
the
1­
hour
ozone
standard
in
2007
and
that
the
revisions
will
not
interfere
with
any
other
applicable
CAA
standard
(
including
8­
hour
ozone).
EPA
is
approving
these
revisions
82
and
the
revised
motor
vehicle
emission
budget
in
this
action.

Comment
M11:
The
commenter
(
Wilson)
commented
that
the
emissions
estimates
for
heavy­
duty
trucks
do
not
use
the
best
available
information
and
cites
a
memo
from
Rick
Baker
of
ERG
to
Hazel
Barbour
(
TCEQ)
dated
August
30,
2003
that
indicates
the
2007
mobile
inventory
may
be
underestimated
by
up
to
3.7
tpd
of
NOx
due
to
heavy­
duty
trucks
not
being
reflashed.
The
commenter
also
noted
that
as
of
November
2004,
only
12.7
percent
of
the
applicable
trucks
nationally
had
been
reflashed.
The
commenter
also
commented
that
the
EPA
default
"
reflash"
rate
of
90
percent
for
heavy­
duty
diesel
trucks
was
inappropriate
for
use
in
development
of
the
2007
on­
road
emissions
inventory.

Response
M11:
The
commenter
is
correct
in
noting
that
under
a
1998
consent
decree
with
EPA,
manufacturers
of
diesel
truck
engines
are
required
to
install
software
upgrades
(
reflash)
to
engines
they
sold
between
1993
and
1998
with
"
defeat
devices"
that
resulted
in
higher
NOx
emissions
than
allowed
by
applicable
certification
standards.
All
States
except
California
are
required
to
use
the
latest
available
version
of
EPA's
MOBILE
emissions
model
for
on­
road
SIP
inventory
development
purposes.
In
addition,
States
are
encouraged
to
use
EPA
guidance
when
using
the
MOBILE
model
for
SIP
purposes.
The
latest
version
of
the
MOBILE6.2
User's
Guide
(
dated
August
14,
2003)
can
be
found
at
http://
www.
epa.
gov/
otaq/
m6.
htm.
The
User's
Guide
indicates
that
a
default
effectiveness
rate
of
90
percent
should
be
used,
unless
good
local
data
is
available.

While
the
commenter
is
correct
that
some
local
data
with
estimates
of
how
many
trucks
83
had
been
reflashed
in
2002
and
nationally
in
2004
exists,
the
consent
decree
still
requires
all
the
trucks
to
be
reflashed
by
2008.
With
the
compliance
date
of
2008
for
the
consent
decree,
EPA
has
not
changed
the
recommended
default
value
of
90
percent
for
2007.
While
reflash
rates
may
have
been
slow
and
below
expected
levels
in
2002
and
2004,
the
flash
rate
did
increase
from
2
percent
in
2002
to
12
percent
in
2004
according
to
the
comment.
Furthermore,
EPA
still
expects
the
consent
decree
to
be
met
in
2008,
so
a
high
compliance
rate
in
2007
is
thought
to
be
an
appropriate
estimate.
TCEQ
modeled
2007
emissions
with
the
EPA
recommended
default
rate
of
90
percent
reflash
rate
and
decided
to
utilize
EPA
defaults.
EPA
concurred
at
the
time
that
this
was
an
acceptable
assumption.
Furthermore
in
March
2006,
EPA
issued
a
letter
to
TCEQ
confirming
that
for
the
8­
hr
ozone
SIP,
that
TCEQ
could
use
EPA
defaults
for
the
MOBILE
emission
estimates
for
the
truck
population
subject
to
the
reflash
requirement.

Comment
M12:
The
commenter
(
Wilson)
commented
that
the
TCEQ
has
not
revised
off­
road
and
area
emissions
to
account
for
operations
of
two
permitted
container
and
cruise
ship
port
facilities.
The
commenter
indicated
that
they
did
not
believe
the
current
SIP
revision
fully
accounts
for
operating
emissions
related
to
the
rapid
growth
in
port
facilities
in
the
Houston
region
including
ship,
train
and
truck
emissions
that
would
also
increase
as
a
result
of
the
port
activity.
The
commenter
asks
EPA
to
evaluate
whether
these
ports
and
the
associated
growth
emissions
were
included
in
the
proposed
SIP
revision.

Response
M12:
The
projected
2007
shipping
inventory
explicitly
accounts
for
traffic
to/
from
the
new
Bayport
container
and
cruise
terminals.
The
shipping
inventory
does
not
account
for
the
Texas
City
container
terminal,
which
was
approved
long
after
the
current
inventory
was
84
developed.
However,
even
though
the
facility
plans
to
open
in
2006,
the
level
of
activity
through
2007
will
likely
be
fairly
modest.
The
TCEQ
plans
to
revise
its
shipping
inventory
to
include
emissions
associated
with
this
new
port
in
future
modeling
work.

Future
ship
and
train
emissions
are
normally
accounted
for
by
growth
factors
developed
by
applying
econometric
growth
forecasts
as
was
done
in
this
case.
During
EPA's
review
of
the
Bayport
Draft
EIS's,
we
reviewed
the
estimated
emissions
from
increased
ship
traffic
from
the
new
ports
and
the
total
was
less
than
the
growth
amount
in
tpd
of
NOx
that
TCEQ
had
included
for
2007
modeling
in
this
SIP.

TCEQ
estimated
train
emissions
by
growing
the
area­
wide
inventory
according
to
projected
trends.
Because
there
is
insufficient
information
available
to
allocate
emissions
of
locomotives
to
specific
track
segments,
the
growth
was
spread
across
all
the
track
miles
in
the
8
county
area
equally.
TCEQ
has
a
project
to
improve
Texas
locomotive
emissions
and
it's
results
should
be
added
to
the
model
for
the
8­
hour
SIP.

Truck
emissions
are
based
on
travel­
demand
modeling
conducted
by
HGAC,
which
included
the
Bayport
and
Texas
City
terminals
in
the
2007
inventories
it
generated
for
TCEQ's
future
case
modeling.

Comment
M13:
The
commenter
(
Wilson)
indicates
that
TCEQ
continues
to
claim
credit
for
emission
reductions
from
the
institution
of
Federal
DOE
standards
on
certain
appliances
even
though
TCEQ
has
dropped
these
measures
from
their
attainment
modeling.
The
commenter
85
states
that
if
these
measures
have
been
dropped,
then
EPA
should
provide
a
reference
for
this
change.

Response
M13:
In
the
previous
SIP,
TCEQ
had
included
the
DOE
energy
efficiency
benefits
as
a
gap
measure
but
had
not
modeled
the
reductions.
The
HGB
area
is
part
of
a
NOx
Cap
and
Trade
program
and
any
reductions
due
to
increases
in
energy
efficiency,
including
federal
appliance
energy
efficiency
programs,
could
help
utilities
maintain
their
cap
and
might
not
yield
actual
reductions
to
the
HGB
airshed.
While
federal
(
DOE)
appliance
energy
efficiency
programs
still
exist,
TCEQ
has
dropped
taking
credit
for
these
programs
in
this
SIP
revision
because
of
the
HGB
Cap
and
Trade
program.
TCEQ
did
not
include
any
potential
emission
reductions
in
this
SIP
revision
that
may
occur
for
other
areas
of
Texas
from
DOE
appliance
energy
efficiency
programs.

Comment
M14:
The
commenter
indicates
that
EPA
should
not
approve
a
plan
that
fails
to
require
industry
to
reduce
emissions
of
OVOCs.
The
commenter
refers
to
the
comment
on
OVOC
modeling
sensitivity
to
substantiate
their
comment.
Furthermore,
the
commenter
refers
to
presentations
by
TCEQ
and
a
report
by
TCEQ
indicating
that
large
amounts
of
VOC
reactivity
from
OVOC
and
HRVOCs
could
yield
ozone
based
on
analysis
of
Auto
gas
chromatographs
that
are
not
part
of
the
chemicals
compounds
covered
by
the
HRVOC
rules.

The
presentations
and
reports
indicated
were:
John
R.
Jolly,
Fernando
I.
Mercado,
and
David
W.
Sullivan,
"
A
Comparison
of
Ambient
and
Emissions
VOC
to
NOx
Ratios
at
Two
Monitors
in
Houston,
Texas"
(
Texas
Commission
on
Environmental
Quality,
June
2004).
Mark
Estes
et
al,
"
Analysis
of
Automated
Gas
Chromatograph
Data
from
1996­
2001
to
Determine
VOCs
with
86
Largest
Ozone
Formation
Potential"
(
TCEQ
Technical
Support
Document
Attachment
6,

December
2002).
Mark
Estes,
"
VOC
Reactivity
Before,
During
and
After
TexAQS
2000"

(
Presentation
to
TexAQS
Science
Meeting,
February
2004).
John
Jolly
and
Elaine
Schroeder,

"
Analysis
of
HGB
Enhanced
Industry­
Sponsored
Monitoring
(
EISM)
Data"
(
Presentation
to
EISM
Network
Stakeholder
Meeting,
as
updated
April
2004).
John
Jolly
et
al,
"
An
Analysis
of
VOC
Reactivity
in
Houston"
(
TCEQ
SIP
Technical
Support
Document
Appendix
GG,
January
23,
2004).

Response
M14:
See
Response
to
Comment
M9
for
EPA's
comments
on
the
analysis
of
sensitivity
modeling
of
OVOCs.
EPA
is
approving
this
package
because
it
has
demonstrated
that
the
area
will
attain
the
1­
hour
ozone
standard
by
November
15,
2007
and
that
no
additional
reductions
were
determined
to
be
needed
by
TCEQ.
EPA
had
previously
reviewed
the
presentations
and
reports
that
the
commenter
refers
to
in
their
comment,
prior
to
our
proposed
action
on
these
SIP
revisions.
These
studies
do
suggest
that
more
information
is
needed
on
the
imputing
of
OVOCs,
but
they
do
not
in
and
of
themselves
provide
enough
of
a
technical
basis
to
take
action
on
imputing
OVOCs
at
this
time.
EPA
encourages
TCEQ
to
continue
to
evaluate
OVOCs
and
other
HRVOCs
and
consider
regulating
sources
of
these
chemical
compounds
if
modeling
indicates
that
their
control
is
necessary
for
attainment
of
the
8­
hour
ozone
NAAQS.

Comment
M15a:
The
commenter
indicates
that
EPA
cannot
assume
the
level
of
control
effectiveness
claimed
by
the
TCEQ
for
regulating
HRVOCs.
The
commenter
indicates
that
TCEQ
failed
to
provide
an
estimate
of
rule
effectiveness
that
takes
into
account
that
the
sources
it
regulates
may
not
sufficiently
encompass
the
major
sources
of
HRVOCs,
and
to
address
the
87
specific
challenges
of
enforcement
and
implementation.
The
commenter
continued
that
TCEQ
did
not
consider
evaporative
emissions
from
rail
tank
cars
and
fugitive
emissions
from
above
ground
and
underground
pipelines
carrying
petroleum
products
and
from
barges.

Response
M15a:
Aircraft
flights
and
other
monitoring
during
and
since
the
TexAQS
2000
study
have
indicated
a
significant
under­
reporting
of
emissions
of
HRVOCs
that
are
emitted
primarily
from
industrial
sources.
As
previously
discussed
in
our
proposed
approval
notice
(
70
FR
58119)
and
the
TSD,
EPA
believes
that
the
field
data
collected
in
2000
and
since
indicates
that
rule
effectiveness
has
been
previously
overestimated
for
sources
of
HRVOCs.
TCEQ
significantly
increased
the
basecase
2000
inventory
for
industrial
sources
of
HRVOC
by
imputing
the
inventory
to
correct
for
the
over
estimation
of
rule
effectiveness
and
to
bring
the
2000
HRVOC
rule
effectiveness
estimate
in
line
with
the
available
ambient
data
that
has
been
collected.
EPA
believes
TCEQ's
adjustment
to
the
basecase
inventory
is
appropriate
based
on
the
information
available.
TCEQ
then
adopted
HRVOC
rules
to
reduce
emissions
of
HRVOCs
and
put
in
place
additional
monitoring
to
maintain
compliance
with
the
new
limits
on
HRVOCs.

Because
of
these
changes
by
TCEQ,
EPA
finds
that
rule
effectiveness
is
adequate
for
the
HRVOC
program.

Having
identified
that
HRVOC's
need
to
be
reduced,
as
discussed
elsewhere,
TCEQ
adopted
rules
for
the
control
of
HRVOC's.
As
discussed
elsewhere,
TCEQ
has
implemented
an
annual
HRVOC
cap
to
reduce
emissions
of
HRVOCs.
TCEQ
reduced
the
annual
HRVOC
cap
levels
that
were
set
in
the
regulations
by
5
percent
compared
to
modeled
levels
in
setting
the
HRVOC
annual
cap
limits
in
part
to
address
rule
effectiveness
and
emission
characterization
88
concerns
regarding
daily
variability
in
emissions
and
geographical
variability
of
location
of
emissions.
These
HRVOC
rules
also
incorporated
stronger
monitoring,
recordkeeping,
and
reporting
than
previous
versions
of
rules
for
the
control
of
VOCs.
Therefore
EPA
believes
that
future
rule
effectiveness
will
be
much
improved
over
the
past.

Specifically,
TCEQ
now
requires
direct
continuous
measurement
of
flow
and
heating
value
of
the
flow
to
flares,
which
is
a
vast
improvement
over
the
past
practice
using
engineering
estimates
and
one
time
tests.
TCEQ
also
requires
monitoring
of
flow
and
concentration
to
cooling
towers
giving
a
direct
measurement
of
emissions.
When
direct
measurements
are
used,

no
rule
effectiveness
adjustment
is
necessary.
Finally
for
fugitive
emissions,
TCEQ
is
requiring
third
party
audits
that
will
be
used
to
confirm
that
the
expected
rule
effectiveness
has
been
achieved
for
the
leak
detection
and
repair
program.
TCEQ
has
agreed
to
utilize
the
available
data,
including
the
first
third
party
audits,
to
conduct
a
rule
effectiveness
study
in
2006
and
include
this
analysis
in
development
of
future
SIPs.

EPA
believes
that
certain
past
practices
are
being
improved
to
reduce
the
uncertainty
of
the
estimates.
In
particular,
the
uncertainty
introduced
by
certain
assumptions
of
control
efficiency
and
rule
effectiveness
is
being
improved.
This
approach
of
reassessing
rule
effectiveness
when
additional
data
is
available
is
consistent
with
EPA's
guidance
on
how
to
address
rule
effectiveness
(
EPA
memo
on
rule
effectiveness
from
Sally
Shaver
dated
April
27,

1995;
and
guidance
document
EPA­
452/
4­
94­
001,
RULE
EFFECTIVENESS
GUIDANCE:

INTEGRATION
OF
INVENTORY,
COMPLIANCE,
AND
ASSESSMENT
APPLICATIONS).
EPA
is
approving
the
emission
reductions
that
have
been
projected
for
the
89
improved
fugitive
emissions
rules
because
the
new
measurement
and
monitoring
requirements
in
the
adopted
rule
will
result
in
significantly
improved
accuracy.
In
addition,
Texas
has
committed
to
perform
a
rule
effectiveness
study
and
use
improved
emission
inventory
techniques
to
estimate
future
emissions
and
confirm
the
effectiveness
of
the
program.

It
is
EPA's
position
that
VOC
emissions
and
some
HRVOC
emissions
could
occur
from
the
sources
that
the
commenter
mentions
and
are
outside
the
traditional
TCEQ
regulatory
field
(
evaporative
emissions
from
rail
cars
in
transit,
barges
in
transit,
pipelines,
etc.).
TCEQ
has
followed
EPA
guidelines
in
estimating
emissions
from
these
sources
in
development
of
the
Emission
Inventory
for
this
revision.
The
initial
field
monitoring
data
that
indicated
these
may
be
areas
underestimated
by
traditional
EPA
guidelines
was
only
starting
to
be
available
in
2003­
2004
time
frame
as
TCEQ
was
developing
this
revision.
At
the
time
TCEQ
was
developing
this
revision,
there
was
not
a
sufficient
body
of
data
to
allow
for
any
estimation
of
the
level
of
emissions
that
may
exist
from
these
sources
that
are
not
in
the
inventory
currently.

EPA
believes
that
the
inventory
reflects
the
best
estimate
of
emissions
that
was
possible
at
the
time.
Inventory
analysis
is
always
an
ongoing
process
that
is
constantly
needing
to
be
improved.
TCEQ
will
continue
to
investigate
and
improve
emission
estimates.
Furthermore,

the
investigation
into
these
potential
sources
of
error
in
the
emission
inventory
will
lead
to
better
science
and
planning
of
effective
control
packages
to
attain
the
8­
hour
standard.
We
encourage
TCEQ
and
others
to
continue
to
use
imaging
devices
and
other
technologies
to
help
refine
emission
inventories.

Comment
M15b:
The
commenter
indicated
that
they
were
concerned
with
HRVOC
fugitive
90
rules
for
leak
monitoring
that
seem
to
place
determination
of
the
threshold
with
the
source
under
TCEQ
rules
section
115.781(
f).
The
commenter
felt
that
the
rules
should
specifically
state
that
TCEQ
retains
the
discretion
to
determine
monitoring
intervals.

The
commenter
indicated
that
EPA
should
not
approve
backsliding
on
the
fugitive
rules
for
facilities
not
in
HRVOC
service
in
the
Houston
region.
The
commenter
further
expressed
concern
that
inspectors
and
enforcement
actions
would
be
hindered
by
the
removal
of
language
on:
(
1)
specifying
the
procedure
that
must
be
used
to
demonstrate
that
leaking
components
cannot
be
repaired
without
a
process
unit
shutdown,
(
2)
specifying
the
requirements
for
undertaking
extraordinary
efforts
to
control
leaks,
(
3)
requiring
the
use
of
electronic
data
collection
devices
during
monitoring,
use
of
an
electronic
database,
and
documentation
of
an
auditing
process
to
assure
proper
calibration,
identify
response
time
failures,
and
assess
pace
anomalies.
These
changes
were
in
changes
in
Texas
regulations
section
115.352
and
115.354.

Response
M15b:
EPA
disagrees
with
the
assertion
from
the
commenter
that
TCEQ
rules
section
115.78(
f)
and
other
parts
of
the
new
HRVOC
rules
place
determination
of
threshold
with
the
source.
The
rules
(
section
115.788
(
a­
d))
require
third
party
audits
of
the
HRVOC
monitoring
at
a
facility,
including
115.78(
f)
requirements
to
be
conducted
and
submitted
to
TCEQ.
If
these
third
party
audits
raise
deficiencies,
section
115.788(
e)
requires
the
source
to
submit
a
corrective
action
plan
to
TCEQ.
Furthermore,
Texas
rules
section
115.788(
f)
allows
for
TCEQ
and
EPA
to
conduct
audits.
Upon
review
of
audit
results,
Texas
rules
section
115.788(
h)
allow
the
TCEQ
to
specify
additional
corrective
actions.
Therefore,
EPA
believes
that
TCEQ
retains
authority
to
determine
compliance
with
section
115
HRVOC
rules,
including
91
section
115.78(
f).

The
commenter
is
correct
that
some
of
the
minor
rule
changes
on
sources
in
fugitive
service
may
be
considered
a
relaxation
of
previous
Texas
regulations
(
115.352
and
115.354),

but
all
three
changes
identified
were
changes
that
Texas
has
made
to
rules
they
previously
adopted
at
the
state
level
in
2002.
The
rules
that
were
changed
were
never
approved
into
the
federal
SIP.
Therefore
these
changes
are
not
a
relaxation
of
the
federally
approved
SIP.
Many
other
changes
to
regulation
115,
regarding
VOC
controls,
strengthen
the
SIP
and
are
considered
in
the
more
detail
in
our
TSD.
EPA
disagrees
with
the
commenter
and
does
not
consider
this
a
backsliding
issue
of
federally
approved
measures.

Comment
M15c:
The
commenter
concerns
about
flare
efficiency
related
to
too
much
air
or
steam
assist
and
high
winds,
and
questioned
what
impact
these
factors
can
have
on
a
flare's
destruction
efficiency.
The
commenter
indicated
that
EPA
should
not
approve
rule
language
that
may
discourage
research
and
application
of
monitoring
technology
to
verify
destruction
efficiencies
or
the
use
of
remote
technology
to
determine
destruction
efficiencies.

Response
M15c:
We
are
approving
the
estimates
used
for
flare
destruction
efficiency
because
the
estimates
are
based
on
the
best
scientific
information
available.
Like
the
commenter,
we
are
concerned
by
the
uncertainty
introduced
by
having
a
significant
source
of
emissions
which
cannot
be
directly
measured.
We
also
share
concerns
that
several
factors
can
potentially
impact
flare
destruction
efficiency,
including
wind
speed
and
volumes
to
the
flare
as
well
as
how
it
is
operated,
but
the
current
estimates
are
based
on
the
best
information
available
at
the
time
92
these
SIP
revisions
were
completed.
We
believe
Texas
should
strongly
consider
requirements
for
monitoring
steam
and
air
assist
ratios
to
insure
that
operators
maintain
these
parameters
in
a
range
to
insure
optimum
combustion.
We
also
encourage
TCEQ
to
pursue
new
technology
such
as
the
Fourier
Transform
Infra­
red
Spectrophotometer
to
eventually
be
able
to
directly
measure
destruction
efficiency
in
the
field.

Comment
M15d:
The
commenter
indicated
that
EPA
should
evaluate
if
interlock
devices
that
regulate
the
ratio
of
air
(
or
steam)
should
be
considered
reasonably
available
control
measures
(
RACM),
and
that
EPA
should
not
approve
this
SIP
unless
TCEQ
develops
regulations
requiring
the
use
of
interlock
devices.

Response
M15d:
We
covered
the
changes
to
TCEQ's
previously
approved
RACM
in
detail
in
the
proposal
(
70
FR
58119)
and
TSD.
EPA
determined
that
all
reasonably
available
control
measures
were
being
implemented
in
the
Houston
area.
In
section
II.
a.
of
the
TSD
(
pages
51­
56),
we
discuss
EPA's
analysis
that
the
revised
plan
will
achieve
attainment
of
the
one­
hour
standard,
based
the
controls
that
will
be
in
place
by
the
ozone
season
of
2007.
As
part
of
the
RACM
analysis
we
estimated
that
to
advance
attainment
more
than
39
tpd
of
additional
NOx
emission
reductions
would
have
to
be
achieved
before
the
ozone
season
of
2006.
EPA
guidance
is
that
a
justification
would
need
to
support
that
a
measure
was
not
reasonably
available
for
that
area
and
could
be
based
on
technological
or
economic
grounds.

The
commenter
indicated
that
EPA
should
consider
requiring
interlock
devices
as
RACM.
The
commenter
did
not
provide
a
potential
quantification
of
how
much
emission
93
reductions
such
a
requirement
would
create
nor
how
such
a
measure
would
result
in
ozone
reductions
such
that
attainment
could
be
achieved
earlier
than
2007.
It
is
not
clear
that
even
if
such
a
requirement
existed
that
it
would
result
in
enough
emission
reductions
to
advance
attainment.
Furthermore,
the
comment
on
the
use
of
interlock
devices
was
not
made
during
TCEQ's
development
of
these
rules
in
2004
and
the
first
time
this
issue
has
been
raised
was
in
the
commenter's
letter
to
EPA
received
in
November
2005.
Even
if
the
interlock
devices
could
result
in
enough
reductions,
it
would
not
have
been
possible
for
TCEQ
to
implement
a
rule
requiring
the
use
of
interlock
devices
and
for
the
applicable
sources
to
achieve
compliance
with
a
interlock
rule
by
the
beginning
of
the
2006
ozone
season.
TCEQ
rule
development
alone
typically
requires
at
least
9­
12
months,
so
just
the
rule
development
timing
would
have
made
it
impossible
to
advance
attainment.
Since
attainment
could
not
be
advanced,
EPA
does
not
consider
a
requirement
for
the
use
of
interlock
devices
to
be
a
potential
RACM
measure.
EPA
does
strongly
encourage
TCEQ
to
consider
the
use
of
interlock
devices
in
the
development
of
the
8­
hour
attainment
demonstration
for
HGB.

Comment
M16:
The
commenter
indicates
that
EPA
should
discount
any
emission
reduction
benefit
from
the
Environmental
Monitoring
Response
System
(
EMRS).
The
commenter
cited
a
comment
from
the
TSD
for
this
action
indicating
that
EPA
"
believes
the
added
scrutiny
of
ambient
VOC
levels
will
provide
feedback
to
industry
on
the
activities
that
may
be
causing
increased
VOC
emissions
resulting
in
improved
overall
program
effectiveness
and
possibly
identifying
previously
unknown
sources
of
emissions."
The
commenter
then
commented
that
TCEQ
had
recently
reported
that
the
goal
of
stopping
HRVOC
events
in
real
time
can
not
be
achieved
with
EMRS.
The
commenter
concludes
that
EPA
should
not
find
that
the
EMRS
94
system
will
result
in
emission
reductions
which
have
not
been
accounted
for
in
the
model.

Response
M16:
EPA
was
aware
that
TCEQ
was
trying
to
stop
HRVOC
events
in
real
time
with
the
EMRS.
During
the
proposal
and
development
of
the
EMRS
program
and
to
this
date,

we
were
skeptical
that
this
could
be
done
considering
the
meteorology
and
density
of
sources
in
wind
sectors
around
the
monitors.
We
do
think
that
the
data
and
continued
focus
on
what
compounds
are
emitted
and
alerting
the
sources
is
a
worthwhile
project
and
should
continue
to
aid
in
finding
new
sources
or
issues
that
will
improve
the
understanding
of
ozone
formation
and
exceedances
in
the
HGB
area.
We
do
think
that
it
will
also
be
a
tool
to
help
determine
what
facilities
or
group
of
facilities
should
be
evaluated
further
in
solving
HGB's
air
quality
issues.

Comment
M17:
The
commenter
indicates
that
EPA
should
not
approve
the
NOx
emission
reduction
relaxations
as
these
changes
will
be
needed
for
further
progress
on
the
8­
hour.

The
commenter
commented
that
in
at
least
one
case
the
ESAD
level
adopted
by
Texas
was
higher
than
required
by
California.
The
commenter
indicated
that
the
California
standard
was
for
gas
fired
utility
boilers
with
a
capacity
greater
than
100
mmBtu/
Hr
is
0.02­
0.03
lbs/
mmBtu,
whereas
the
Texas
standard
is
0.03
lb/
mmBtu.
The
commenter
continues
that
TCEQ
should
provide
an
evaluation
for
each
difference
in
ESADs
that
are
being
changed
with
these
NOx
MECT
revisions
and
explain
why
the
lower
ESAD
was
not
utilized
and
until
this
is
completed
EPA
should
not
approve
these
revisions.
95
Response
M17:
EPA
has
reviewed
this
SIP
revision
package
and
determined
that
the
package
demonstrates
attainment
of
the
1­
hour
ozone
NAAQS.
As
explained
above,
this
submission
was
not
for
the
purpose
of
addressing
reasonable
further
progress
forward
and
attainment
of
the
8­
hour
NAAQS.
Texas
is
undertaking
a
significant
and
intense
new
air
study
(
TexAQS
II)
in
HGB.
With
this
new
information
coming
in
and
new
8­
hour
modeling
taking
place
it
is
to
early
to
determine
what
the
appropriate
suite
of
control
measures
will
be
for
8­
hour
attainment.

TCEQ
is
in
the
process
of
developing
the
8­
hour
demonstrations
which
are
due
to
EPA
on
June
15,
2007.

EPA
reviewed
the
RACM
levels
as
discussed
in
a
previous
response
and
in
the
TSD
for
this
action.
The
Texas
standard
is
within
the
range
(
although
on
the
high
end)
of
the
ESAD
for
the
California
rule
and
was
reviewed
prior
to
proposal
and
determined
to
be
acceptable
for
RACM.
EPA
conducted
a
review
of
the
changes
to
ESAD
levels
and
documented
California
levels
for
each
source
category
and
Texas
90
percent
and
80
percent
in
Table
6.
B­
1
of
the
TSD
and
determined
the
levels
to
be
acceptable.
Furthermore,
as
indicated
in
a
previous
response
there
are
no
additional
measures
that
could
be
implemented
to
advance
the
attainment
date
sooner
than
the
current
attainment
date
in
2007.
96
Statutory
and
Executive
Order
Reviews
Under
Executive
Order
12866
(
58
FR
51735,
October
4,
1993),
this
action
is
not
a
"
significant
regulatory
action"
and
therefore
is
not
subject
to
review
by
the
Office
of
Management
and
Budget.
For
this
reason
and
because
this
action
will
not
have
a
significant,

adverse
effect
on
the
supply,
distribution,
or
use
of
energy,
this
action
is
also
not
subject
to
Executive
Order
13211,
"
Actions
Concerning
Regulations
That
Significantly
Affect
Energy
Supply,
Distribution,
or
Use"
(
66
FR
28355,
May
22,
2001).
This
action
merely
approves
state
law
as
meeting
Federal
requirements
and
imposes
no
additional
requirements
beyond
those
imposed
by
state
law.
Accordingly,
the
Administrator
certifies
that
this
rule
will
not
have
a
significant
economic
impact
on
a
substantial
number
of
small
entities
under
the
Regulatory
Flexibility
Act
(
5
U.
S.
C.
601
et
seq.).
Because
this
rule
approves
pre­
existing
requirements
under
state
law
and
does
not
impose
any
additional
enforceable
duty
beyond
that
required
by
state
law,
it
does
not
contain
any
unfunded
mandate
or
significantly
or
uniquely
affect
small
governments,
as
described
in
the
Unfunded
Mandates
Reform
Act
of
1995
(
Public
Law
104­
4).

This
rule
also
does
not
have
tribal
implications
because
it
will
not
have
a
substantial
direct
effect
on
one
or
more
Indian
tribes,
on
the
relationship
between
the
Federal
Government
and
Indian
tribes,
or
on
the
distribution
of
power
and
responsibilities
between
the
Federal
Government
and
Indian
tribes,
as
specified
by
Executive
Order
13175
(
65
FR
67249,
November
9,
2000).
This
action
also
does
not
have
Federalism
implications
because
it
does
not
have
substantial
direct
effects
on
the
States,
on
the
relationship
between
the
national
government
and
97
the
States,
or
on
the
distribution
of
power
and
responsibilities
among
the
various
levels
of
government,
as
specified
in
Executive
Order
13132
(
64
FR
43255,
August
10,
1999).
This
action
merely
approves
a
state
rule
implementing
a
Federal
standard,
and
does
not
alter
the
relationship
or
the
distribution
of
power
and
responsibilities
established
in
the
CAA.
This
rule
also
is
not
subject
to
Executive
Order
13045
"
Protection
of
Children
from
Environmental
Health
Risks
and
Safety
Risks"
(
62
FR
19885,
April
23,
1997),
because
it
is
not
economically
significant.

In
reviewing
SIP
submissions
under
the
National
Technology
Transfer
and
Advancement
Act
of
1995
(
15
U.
S.
C.
272
note),
EPA's
role
is
to
approve
state
choices,
provided
that
they
meet
the
criteria
of
the
CAA.
In
this
context,
in
the
absence
of
a
prior
existing
requirement
for
the
State
to
use
voluntary
consensus
standards
(
VCS),
EPA
has
no
authority
to
disapprove
a
SIP
submission
for
failure
to
use
VCS.
It
would
thus
be
inconsistent
with
applicable
law
for
EPA,
when
it
reviews
a
SIP
submission,
to
use
VCS
in
place
of
a
SIP
submission
that
otherwise
satisfies
the
provisions
of
the
CAA.
Thus,
the
requirements
of
section
12(
d)
of
the
National
Technology
Transfer
and
Advancement
Act
of
1995
do
not
apply.
This
rule
does
not
impose
an
information
collection
burden
under
the
provisions
of
the
Paperwork
Reduction
Act
of
1995
(
44
U.
S.
C.
3501
et
seq.).

The
Congressional
Review
Act,
5
U.
S.
C.
section
801
et
seq.,
as
added
by
the
Small
Business
Regulatory
Enforcement
Fairness
Act
of
1996,
generally
provides
that
before
a
rule
may
take
effect,
the
agency
promulgating
the
rule
must
submit
a
rule
report,
which
includes
a
copy
of
the
rule,
to
each
House
of
the
Congress
and
to
the
Comptroller
General
of
the
United
98
States.
EPA
will
submit
a
report
containing
this
rule
and
other
required
information
to
the
U.
S.

Senate,
the
U.
S.
House
of
Representatives,
and
the
Comptroller
General
of
the
United
States
prior
to
publication
of
the
rule
in
the
Federal
Register.
A
major
rule
cannot
take
effect
until
60
days
after
it
is
published
in
the
Federal
Register.
This
action
is
not
a
"
major
rule"
as
defined
by
5
U.
S.
C.
section
804(
2).

Under
section
307(
b)(
1)
of
the
CAA,
petitions
for
judicial
review
of
this
action
must
be
filed
in
the
United
States
Court
of
Appeals
for
the
appropriate
circuit
by
[
FEDERAL
REGISTER
OFFICE:
insert
date
60
days
from
date
of
publication
of
this
document
in
the
Federal
Register].
Filing
a
petition
for
reconsideration
by
the
Administrator
of
this
final
rule
does
not
affect
the
finality
of
this
rule
for
the
purposes
of
judicial
review
nor
does
it
extend
the
time
within
which
a
petition
for
judicial
review
may
be
filed,
and
shall
not
postpone
the
effectiveness
of
such
rule
or
action.
This
action
may
not
be
challenged
later
in
proceedings
to
enforce
its
requirements.
(
See
section
307(
b)(
2).)
99
List
of
Subjects
in
40
CFR
Part
52
Environmental
protection,
Air
pollution
control,
Carbon
monoxide,
Incorporation
by
reference,
Intergovernmental
relations,
Nitrogen
dioxide,
Ozone,
Particulate
matter,
Reporting
and
recordkeeping
requirements,
Volatile
organic
compounds.

Dated:
August
24,
2006
Richard
E.
Greene,

Regional
Administrator,
Region
6.
100
40
CFR
part
52
is
amended
as
follows:

PART
52
­
[
AMENDED]

1.
The
authority
citation
for
part
52
continues
to
read
as
follows:

Authority:
42
U.
S.
C.
7401
et
seq.

Subpart
SS
 
Texas
2.
Section
52.2270
is
amended
as
follows:

a.
The
table
in
paragraph
(
c)
entitled
"
EPA
Approved
Regulations
in
the
Texas
SIP"
is
amended
as
follows:

1.
By
revising
entries
for
Sections
114.1
and
114.2
under
Chapter
114
(
Reg
4),

Subchapter
A.

2.
By
revising
the
heading
entitled
"
Subchapter
B:
Vehicle
Inspection
and
Maintenance"
under
Chapter
114
(
Reg
4)
to
read
"
Subchapter
C
 
Vehicle
Inspection
and
Maintenance;
Low
Income
Vehicle
Repair
Assistance,
Retrofit,
and
Accelerated
Vehicle
Retirement
Program;
and
Early
Action
Compact
Counties";
adding
a
new
centered
heading
"
Division
1:
Vehicle
Inspection
and
Maintenance"
immediately
following
it;
revising
entries
for
Sections
114.50,
114.52,
and
114.53;
and
removing
the
heading
entitled
"
Subchapter
C
 

Vehicle
Inspection
and
Maintenance;
Low
Income
Vehicle
Repair
Assistance,
Retrofit,
and
Accelerated
Vehicle
Retirement
Program;
and
Early
Action
Compact
Counties"
that
follows
Section
114.53.

3.
By
removing
the
heading
entitled
"
Division
6:
Lawn
Service
Equipment
Operating
Restrictions"
under
Chapter
114
(
Reg
4),
Subchapter
I;
and
removing
entries
for
Sections
114.452
and
114.459.

4.
By
removing
the
heading
entitled
"
Division
1:
Motor
Vehicle
Idling
101
Limitations"
under
Chapter
114
(
Reg
4),
Subchapter
J;
and
removing
entries
for
Sections
114.500,
114.502,
114.507,
and
114.509.

5.
By
revising
the
heading
entitled
"
Chapter
117
(
Reg
7)
 
Control
of
Air
Pollution
from
Nitrogen
Compounds
 
Subchapter
A"
to
read
"
Chapter
117
(
Reg
7)
 

Control
of
Air
Pollution
from
Nitrogen
Compounds";
adding
a
centered
heading
entitled
"
Subchapter
A
 
Definitions"
immediately
following
it;
and
revising
the
entry
for
Section
117.10.

6.
By
revising
the
heading
entitled
"
Subchapter
B
 
Division
1
 
Utility
Electric
Generation
in
Ozone
Nonattainment
Areas"
under
Chapter
117
(
Reg
7)
to
read
"
Subchapter
B
 
Combustion
at
Major
Sources";
adding
a
centered
heading
entitled
"
Division
1:
Utility
Electric
Generation
in
Ozone
Nonattainment
Areas"
immediately
following
it;

removing
the
entry
for
117.104;
and
revising
entries
for
Sections
117.105
­
117.108,
117.113
­

117.116,
117.119,
117.131,
117.135,
117.138,
117.141,
117.143,
117.149,
117.203,
117.205
­

117.207,
117.213
­
117.216,
117.219,
and
117.223.

7.
By
revising
the
heading
entitled
"
Subchapter
C
 
Division
1
 
ADIPIC
Acid
Manufacturing"
under
Chapter
117
(
Reg
7)
to
read
"
Subchapter
C
 
Acid
Manufacturing";

adding
a
centered
heading
entitled
"
Division
1:
ADIPIC
Acid
Manufacturing"
immediately
following
it;
and
revising
entries
for
Sections
117.301,
117.309,
117.311,
117.313,
117.319,

117.321,
117.401,
117.409,
117.411,
117.413,
117.419,
and
117.421.

8.
By
revising
the
heading
entitled
"
Subchapter
D
 
Water
Heaters,
Small
Boilers,
and
Process
Heaters"
under
Chapter
117
(
Reg
7)
to
read
"
Subchapter
D
 
Small
Combustion
Sources";
adding
a
new
centered
heading
"
Division
1:
Water
Heaters,
Small
Boilers,
and
Process
Heaters"
immediately
following
it;
adding
a
new
centered
heading
102
"
Division
2:
Boilers,
Process
Heaters,
and
Stationary
Engines
and
Gas
Turbines
at
Minor
Sources"
immediately
preceding
the
entry
for
Section
117.471;
and
revising
entries
for
117.463,

117.465,
117.473,
117.475,
117.478,
and
117.479.

9.
By
removing
entries
for
Section
117.540
and
117.560
under
Chapter
117
(
Reg
7),
Subchapter
E;
and
revising
entries
for
117.510,
117.512,
117.520,
and
117.534.

b.
The
second
table
in
paragraph
(
e)
entitled
"
EPA
Approved
Nonregulatory
Provisions
and
Quasi­
Regulatory
Measures
in
the
Texas
SIP"
is
amended
by
adding
a
new
entry
at
the
end
to
read
as
follows:

§
52.2270
Identification
of
plan.

*
*
*
*
*

(
c)
*
*
*

EPA­
Approved
Regulations
in
the
Texas
SIP
State
Citation
Title/
subject
State
approval/
submittal
date
EPA
approval
date
Explanation
*
*
*
*
*
*
*

Chapter
114
(
Reg
4)
 
Control
of
Air
Pollution
from
Motor
Vehicles
Subchapter
A
 
Definitions
Section
114.1
Definitions.
09/
05/
04
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
114.2
Inspection
and
Maintenance
Definitions.
09/
05/
04
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*
103
Subchapter
C
 
Vehicle
Inspection
and
Maintenance;
Low
Income
Vehicle
Repair
Assistance,
Retrofit,
and
Accelerated
Vehicle
Retirement
Program;
and
Early
Action
Compact
Counties
Division
1:
Vehicle
Inspection
and
Maintenance
Section
114.50
Vehicle
Emission
Inspection
Requirements.
09/
05/
04
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
Subsection
114.50(
b)(
2)
is
NOT
part
of
the
approved
SIP.

*
*
*
*
*
*
*

Section
114.52
Early
Participation
Incentive
Program.
09/
05/
04
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
114.53
Inspection
and
Maintenance
Fees.
09/
05/
04
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Division
3:
Early
Action
Compact
Counties
*
*
*
*
*
*
*

Subchapter
I
 
Non­
Road
Engines
*
*
*
*
*
*
*

Section
114.429
Affected
Counties
and
Compliance
Schedules.
12/
06/
00
11/
14/
01,
66
FR
57222
Subchapter
J
 
Operational
Controls
for
Motor
Vehicles
Division
2:
Locally
Enforced
Motor
Vehicle
Idling
Limitations
*
*
*
*
*
*
*

Chapter
117
(
Reg
7)
 
Control
of
Air
Pollution
from
Nitrogen
Compounds
Subchapter
A
 
Definitions
Section
117.10
Definitions.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
104
*
*
*
*
*
*
*

Subchapter
B
 
Combustion
at
Major
Sources
Division
1:
Utility
Electric
Generation
in
Ozone
Nonattaiment
Areas
*
*
*
*
*
*
*

Section
117.103
Exemptions.
09/
26/
01
114/
14/
01,
66
FR
57244
Section
117.105
Emission
Specifications
for
Reasonably
Available
Control
Technology
(
RACT).
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.106
Emission
Specifications
for
Attainment
Demonstrations.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
The
SIP
does
not
include
section
117.106(
d).

Section
117.107
Alternative
System
Emission
Specifications.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.108
System
Cap.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.113
Continuous
Demonstration
of
Compliance.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.114
Emission
Testing
and
Monitoring
for
the
Houston­
Galveston
Attainment
Demonstration.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
105
Section
117.115
Final
Control
Plan
Procedures
for
Reasonably
Available
Control
Technologies.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.116
Final
Control
Plan
Procedures
for
Attainment
Demonstration
Emission
Specifications.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.119
Notification,
Recordkeeping,
and
Reporting
Requirements.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Division
2
 
Utility
Electric
Generation
in
East
and
Central
Texas
Section
117.131
Applicability.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.135
Emission
Specifications.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
The
SIP
does
not
include
section
117.106(
d).

Section
117.138
System
Cap.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.141
Initial
Demonstration
of
Compliance.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
106
Section
117.143
Continuous
Demonstration
of
Compliance.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.149
Notification,
Recordkeeping,
and
Reporting
Requirements.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.203
Exemptions.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.205
Emission
Specifications
for
Reasonably
Available
Control
Technology
(
RACT).
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.206
Emission
Specifications
for
Attainment
Demonstrations.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
The
SIP
does
not
include
section
117.206(
e).

Section
117.207
Alternative
Plantwide
Emission
Specifications.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.213
Continuous
Demonstration
of
Compliance.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.214
Emission
Testing
and
Monitoring
for
the
Houston­
Galveston
Attainment
Demonstration.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
107
Section
117.215
Final
Control
Plan
Procedures
for
Reasonably
Available
Control
Technologies.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.216
Final
Control
Plan
Procedures
for
Attainment
Demonstration
Emission
Specifications.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.219
Notification,
Recordkeeping,
and
Reporting
Requirements.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.223
Source
Cap.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Subchapter
C
 
Acid
Manufacturing
Division
1:
ADIPIC
Acid
Manufacturing
Section
117.301
Applicability.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.309
Control
Plan
Procedures.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.311
Initial
Demonstration
of
Compliance.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
108
Section
117.313
Continuous
Demonstration
of
Compliance.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.319
Notification,
Recordkeeping,
and
Reporting
Requirements.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.321
Alternative
Case
Specific
Specifications.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Division
2:
Nitric
Acid
Manufacturing,
Ozone
Nonattainment
Areas
Section
117.401
Applicability.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.409
Control
Plan
Procedures.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.411
Initial
Demonstration
of
Compliance.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.413
Continuous
Demonstration
of
Compliance.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.419
Notification,
Recordkeeping,
and
Reporting
Requirements.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.421
Alternative
Case
Specific
Specifications.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
109
*
*
*
*
*
*
*

Subchapter
D
 
Small
Combustion
Sources
Division
1:
Water
Heaters,
Small
Boilers,
and
Process
Heaters
*
*
*
*
*
*
*

Section
117.463
Exemptions.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.465
Emission
Specifications.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Division
2:
Boilers,
Process
Heaters,
and
Stationary
Engines
and
Gas
Turbines
at
Minor
Sources
Section
117.471
Applicability.
09/
26/
01
11/
14/
01,
66
FR
57244
New.

Section
117.473
Exemptions.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Section
117.475
Emission
Specifications.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
The
SIP
does
not
include
section
117.475(
i).

Section
117.478
Operating
Requirements.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.479.
Monitoring,
Recordkeeping,
and
Reporting
Requirements.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

*
*
*
*
*
*
*

Subchapter
E
 
Administrative
Provisions
110
Section
117.510
Compliance
Schedule
for
Utility
Electric
Generation
in
Ozone
Nonattaimnent
Areas.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.512
Compliance
Schedule
for
Utility
Electric
Generation
in
East
and
Central
Texas.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.520
Compliance
Schedule
for
Industrial,
Commercial,
and
Institutional
Combustion
Sources
in
Ozone
Nonattainment
Areas.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.534
Compliance
Schedule
for
Boilers,
Process
Heaters,
Stationary
Engines,
and
Gas
Turbines
at
Minor
Sources.
12/
13/
02
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]

Section
117.570
Use
of
Emissions
Credits
for
Compliance.
03/
05/
03
03/
26/
04,
69
FR
15686
*
*
*
*
*
*
*

*
*
*
*
*

(
e)
*
*
*

EPA
Approved
Nonregulatory
Provisions
and
Quasi­
Regulatory
Measures
in
the
Texas
SIP
Name
of
SIP
provision
Applicable
geographic
or
nonattainment
area
State
submittal/
effective
date
EPA
approval
date
Comments
*
*
*
*
*
*
*
111
Attainment
Demonstration
for
Houston/
Galveston/
Brazoria
(
HGB)
One­
hour
Ozone
Nonattainment
Area
Adopting
Strategy
Based
on
NOx
and
Point
Source
Highly­
Reactive
VOC
Emission
Reductions
Houston/
Galves
ton,
TX
12/
01/
04
[
Insert
date
of
FR
publication]
[
Insert
FR
page
number
where
document
begins]
