Document ID: EPA-R09-OAR-2008-0379-0001
Agency: epa
Document Type: Proposed Rule
Title: Approval and Promulgation of Maintenance Plan for Carbon Monoxide; State of Arizona; Tucson Air Planning Area
Posted Date: 2009-08-05T04:00Z

[Federal Register: August 5, 2009 (Volume 74, Number 149)]
[Proposed Rules]               
[Page 39007-39013]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr05au09-35]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2008-0379; FRL-8940-3]

 
Approval and Promulgation of Maintenance Plan for Carbon 
Monoxide; State of Arizona; Tucson Air Planning Area

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: Pursuant to the Clean Air Act, EPA is proposing to approve two 
State implementation plan revisions submitted by the State of Arizona. 
The State submitted the 2008 Revision to the Carbon Monoxide Limited 
Maintenance Plan for the Tucson Air Planning Area on July 10, 2008. EPA 
is proposing to approve the 2008 Limited Maintenance Plan because it 
provides for the maintenance of the carbon monoxide national ambient 
air quality standard within the Tucson Air Planning Area through the 
second 10-year portion of the maintenance period. EPA is also proposing 
to approve a statutory provision that was submitted by the State on 
June 22, 2009 as a revision to the State implementation plan and that 
extends the life of the State's vehicle emissions inspection program 
through the end of 2016. EPA is taking this action pursuant to those 
provisions of the Clean Air Act that obligate the Agency to take action 
on submittals of revisions to State implementation plans. The effect of 
this action would be to make certain commitments related to maintenance 
of the carbon monoxide standard in the Tucson Air Planning Area 
Federally enforceable as part of the Arizona State implementation plan.

DATES: Written comments must be received at the address below on or 
before September 4, 2009.

ADDRESSES: Submit comments, identified by docket number EPA-R09-OAR-
2008-0379, by one of the following methods:
    1. Federal eRulemaking Portal: http://www.regulations.gov. Follow 
the on-line instructions.
    2. E-mail: robin.marty@epa.gov.
    3. Mail or deliver: Marty Robin (AIR-2), U.S. Environmental 
Protection Agency Region IX, 75 Hawthorne Street, San Francisco, CA 
94105-3901.
    Instructions: All comments will be included in the public docket 
without change and may be made available online at http://
www.regulations.gov, including any personal information provided, 
unless the comment includes Confidential Business Information (CBI) or 
other information whose disclosure is restricted by statute. 
Information that you consider CBI or otherwise protected should be 
clearly identified as such and should not be submitted through http://
www.regulations.gov or e-mail. The http://www.regulations.gov portal is 
an ``anonymous access'' system, which means EPA will not know your 
identity or contact information unless you provide it in the body of 
your comment. If you send e-mail directly to EPA without going through 
http://

[[Page 39008]]

www.regulations.gov, your e-mail address will be automatically captured 
and included as part of the comment that is placed in the public docket 
and made available on the Internet. If you submit an electronic 
comment, EPA recommends that you include your name and other contact 
information in the body of your comment and with any disc or CD-ROM you 
submit. If EPA cannot read your comment due to technical difficulties 
and cannot contact you for clarification, EPA may not be able to 
consider your comment. Electronic files should avoid the use of special 
characters, any form of encryption, and be free of any defects or 
viruses.
    Docket: All documents in the electronic docket are listed in the 
http://www.regulations.gov index. Although listed in the index, some 
information is not publicly available, i.e., 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 in http://
www.regulations.gov or in hard copy at EPA Region IX, 75 Hawthorne 
Street, San Francisco, California. To inspect the hard copy materials, 
please schedule an appointment during normal business hours with the 
contact listed in the FOR FURTHER INFORMATION CONTACT section.

FOR FURTHER INFORMATION CONTACT: Marty Robin, Air Planning Office (AIR-
2), Air Division, U.S. Environmental Protection Agency, Region IX, 75 
Hawthorne Street, San Francisco, CA 94105-3901, (415) 972-3961.

SUPPLEMENTARY INFORMATION: Throughout this document, the terms ``we'', 
``us'', and ``our'' refer to EPA.

Table of Contents

I. Summary of EPA's Action
II. Background
III. Arizona's SIP Submittals
IV. EPA's Evaluation of Arizona's SIP Submittals
    A. Procedural Requirements
    B. Substantive Requirements
    1. Attainment Emissions Inventory
    2. Maintenance Demonstration
    3. Monitoring Network and Verification of Continued Attainment
    4. Contingency Plan
    C. Conclusion
V. Transportation and General Conformity
VI. Proposed Action and Public Comment
VII. Statutory and Executive Order Reviews

I. Summary of EPA's Action

    Under the Clean Air Act (CAA or ``Act''), EPA is proposing to 
approve the 2008 Revision to the Carbon Monoxide Limited Maintenance 
Plan for the Tucson Air Planning Area (TAPA) (``2008 CO Maintenance 
Plan''), adopted by the Pima Association of Governments (PAG) on June 
26, 2008, and submitted by the Arizona Department of Environmental 
Quality (ADEQ) as a revision to the Arizona State Implementation Plan 
(SIP) on July 10, 2008. In the 1970s, TAPA was designated as a 
nonattainment area for the carbon monoxide (CO) national ambient air 
quality standard (NAAQS). In 2000, in light of improved ambient CO 
conditions and implementation of permanent CO-emissions-reducing 
measures, EPA approved ADEQ's request to redesignate the TAPA to 
attainment for the CO NAAQS and approved the 1996 Carbon Monoxide 
Limited Maintenance Plan for the Tucson Air Planning Area (``1996 CO 
Maintenance Plan''), which provides for maintenance of the standard for 
the first 10 years after redesignation. The 2008 CO Maintenance Plan 
submitted by ADEQ on July 10, 2008 is designed to maintain the CO 
standard within the TAPA for a second ten-year period beyond 
redesignation, and we are proposing to approve the 2008 CO Maintenance 
Plan because we conclude that it meets all applicable requirements 
under CAA sections 110 and 175A.
    As a general matter, the 2008 CO Maintenance Plan relies on the 
same control measures and contingency provisions to maintain the CO 
NAAQS during the second ten-year portion of the maintenance period as 
the 1996 CO Maintenance Plan relied upon for the first 10-year period. 
One of the control measures, the State's vehicle emissions inspection 
(VEI) program, is subject to a legislative sunset clause. To provide 
for the continuation of the VEI program, on June 22, 2009, ADEQ 
submitted, and EPA is proposing to approve, a SIP revision containing a 
statutory provision that extends the life of the State's VEI program 
through the end of 2016. While the second 10-year maintenance period 
extends until 2020, based on the Arizona's Legislature's support for 
the VEI program in the past, we expect the Legislature to extend the 
life of the VEI program once again prior to 2016.

II. Background

    Carbon monoxide (CO) is a colorless and odorless gas, formed when 
carbon in fuel is not burned completely. It is a component of motor 
vehicle exhaust, which contributes about 60 percent of all CO emissions 
nationwide. High concentrations of CO generally occur in areas with 
heavy traffic congestion. Peak CO concentrations typically occur during 
the colder months of the year when CO automotive emissions are greater 
and nighttime inversion conditions (where air pollutants are trapped 
near the ground beneath a layer of warmer air) are more frequent. CO 
enters the bloodstream through the lungs and reduces oxygen delivery to 
the body's organs and tissues. The health threat from levels of CO 
sometimes found in the ambient air is most serious for those who suffer 
from cardiovascular disease, such as angina pectoris.
    Under the CAA, as amended in 1970, EPA promulgated NAAQS to protect 
public health and welfare for six criteria pollutants, including CO. 
EPA set the NAAQS for CO at 35 parts per million (ppm), one-hour 
average, and 9 ppm, eight-hour average. The CO NAAQS remain the same 
today. See 40 CFR 50.8. Under the CAA, States are required to adopt and 
submit plans to implement, maintain, and enforce the NAAQS throughout 
the State. Such plans are referred to as State Implementation Plans 
(SIPs).
    Pursuant to the CAA, as amended in 1977, EPA designated all areas 
of the country as attainment, nonattainment, or unclassifiable for each 
of the NAAQS. EPA designated the TAPA as nonattainment for the CO NAAQS 
although the specific boundaries of the area have changed over time. 
See 43 FR 8962, at 8968 (March 3, 1978); 44 FR 16388, at 16392 (March 
19, 1979); and 51 FR 27843, at 27844 (August 4, 1986). The current 
boundary of the TAPA defined by township and range as is set forth in 
the CO table contained in 40 CFR 81.303. Pursuant to the CAA as amended 
in 1990, TAPA's nonattainment area designation was carried forward by 
operation of law, but TAPA was not further classified under the 1990 
CAA Amendments because no CO violations had been recorded in the area 
during 1988 and 1989. See 56 FR 56694, at 56716 (November 6, 1991).
    In the mid-1990s, in response to the full implementation of a 
number of CO reduction measures and an extended period during which no 
CO violations were monitored in the TAPA, ADEQ requested redesignation 
of TAPA to ``attainment'' for the CO NAAQS. For EPA to approve a 
redesignation request, among other criteria, a State must submit (and 
EPA approve) a maintenance plan that covers the period extending 10 
years after redesignation. See CAA sections 107(d)(3)(E)(iv) and 175A. 
EPA has published guidance for States on developing such maintenance

[[Page 39009]]

plans.\1\ For certain ``not classified'' CO nonattainment areas (i.e., 
those with design values \2\ at or below 85% of the standard, or 7.65 
ppm, eight-hour average), such as the TAPA, EPA interprets the CAA to 
allow States to develop more limited maintenance plans, referred to as 
Limited Maintenance Plans (LMPs).\3\
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    \1\ Calcagni, John, Director, Air Quality Management Division, 
EPA Office of Air Quality Planning and Standards, ``Procedures for 
Processing Requests to Redesignate Areas to Attainment,'' September 
4, 1992.
    \2\ The design value is the highest of the second high eight-
hour concentrations observed at any site in the area.
    \3\ Paisie, Joseph W., Group Leader, Integrated Policy and 
Strategies Group, EPA Office of Air Quality Planning and Standards, 
``Limited Maintenance Plan Option for Nonclassifiable CO 
Nonattainment Areas,'' October 6, 1995.
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    As the designated metropolitan planning organization (MPO) for the 
Tucson region, the Pima Association of Governments (PAG) is responsible 
under Arizona law for development of nonattainment and maintenance 
plans for the TAPA. PAG opted to develop an LMP for the TAPA, and in 
1997, ADEQ submitted PAG's 1996 Carbon Monoxide Limited Maintenance 
Plan for the Tucson Air Planning Area (``1996 CO Maintenance Plan'') to 
EPA as a revision to the Arizona SIP. In 2000, EPA approved the 1996 CO 
Maintenance Plan and the State's request to redesignate the TAPA to 
attainment for the CO NAAQS. See 65 FR 36353 (June 8, 2000), as 
corrected at 65 FR 50651 (August 21, 2000) and 69 FR 12802 (March 18, 
2004). In connection with our approval of the 1996 CO Maintenance Plan, 
we approved various statutory provisions providing for the continuation 
of the control measures and the authority for State agencies to 
implement the contingency measures upon which the maintenance plan 
relies. One of the approved statutory provisions (i.e., Arizona Revised 
Statutes (ARS) section 41-3009.01) extended the life of the State's VEI 
program through the end of 2008. As the first 10-year maintenance plan, 
the 1996 CO Maintenance Plan was intended to provide for maintenance of 
the CO NAAQS in the TAPA through mid-2010.
    Under CAA section 175A(b), States must submit a revision to the 
maintenance plan eight years after redesignation to provide for 
maintenance of the NAAQS for 10 years following the end of the first 
10-year period. In recognition of the continuing record of monitoring 
data showing ambient CO concentrations in the TAPA well below the LMP 
eligibility threshold (i.e., 7.65 ppm), PAG chose the LMP option again 
for the development of a second 10-year CO maintenance plan. On June 
26, 2008, PAG adopted the second 10-year CO maintenance plan, entitled 
``2008 Revision to the Carbon Monoxide Limited Maintenance Plan for the 
Tucson Air Planning Area (for 2010)'' (herein referred to as the ``2008 
CO Maintenance Plan''), and on July 10, 2008, ADEQ submitted the 2008 
CO Maintenance Plan to EPA as a revision to the Arizona SIP.
    On June 22, 2009, to extend the life of the VEI program through 
most of the second 10-year period, ADEQ submitted a statutory provision 
(ARS section 41-3017.01) as a revision to the Arizona SIP. ARS section 
41-3017.01 extends the life of the State's VEI program until the end of 
2016.
    The 2008 CO Maintenance Plan and VEI-related statutory provision 
are the subjects of today's proposed rule.

III. Arizona's SIP Submittals

    On July 10, 2008, the ADEQ Director adopted and submitted the 2008 
CO Maintenance Plan to EPA as a revision to the Arizona SIP. The 
submittal includes the maintenance plan and appendices as well as 
certification of adoption of the plan by PAG. Appendices to the plan 
include inventory information, certain Arizona statutes, an updated 
interagency memorandum of agreement, a letter from ADEQ regarding the 
continuation of the VEI program, PAG's ``Air Quality Report--2007 
National, State and Tucson Region Trends,'' resolutions from the PAG 
jurisdictions concerning priorities for transportation improvement 
programs (that had been previously submitted and approved by EPA in 
connection with the 1996 CO Maintenance Plan), and documentation of 
notice, hearing, and public participation prior to adoption of the plan 
by the PAG Regional Council on June 26, 2008.
    The 2008 CO Maintenance Plan does not include any additional 
measures but relies on the same strategy as the 1996 CO Maintenance 
Plan to provide for maintenance of the CO NAAQS through 2020. 
Specifically, the measures upon which the second 10-year maintenance 
plan for the TAPA relies include the continuation of the Federal Motor 
Vehicle Control Program (FMVCP), the State's VEI program, the State's 
wintertime oxygenated gasoline program (1.8% oxygen content), and to a 
lesser extent, PAG's Trip Reduction Program and Pima County Department 
of Environmental Quality's (PDEQ's) voluntary no-drive days program. 
The 2008 CO Maintenance Plan also carries forward essentially the same 
contingency plan as contained in the 1996 CO Maintenance Plan.
    On June 22, 2009, ADEQ submitted a supplement to the 2008 CO 
Maintenance Plan that includes ARS section 41-3017.01, a statutory 
provision that extends the life of the State's VEI program until the 
end of 2016, as a revision to the Arizona SIP. In addition to the 
statutory provision itself, ADEQ's June 22, 2009 submittal package 
includes evidence of public notice, public hearing, and adoption.

IV. EPA's Evaluation of Arizona's SIP Submittals

A. Procedural Requirements

    CAA section 110(a)(2) and 110(l) require revisions to a SIP to be 
adopted by the State after reasonable notice and public hearing. EPA 
has promulgated specific procedural requirements for SIP revisions in 
40 CFR part 51, subpart F. These requirements include publication of a 
notice by prominent advertisement in the relevant geographic area of 
proposed SIP revisions, at least a 30-day public comment period, and an 
opportunity for a public hearing.
    Documentation in Appendix H of the 2008 CO Maintenance Plan shows 
that, on March 27, 2008, PAG published a notice of a 30-day comment 
period and a public hearing in newspapers of general circulation in the 
Tucson area. On April 29, 2008, PAG held a public hearing on the 2008 
CO Maintenance Plan. No oral or written comments were submitted, and on 
June 26, 2008, the PAG Regional Council adopted the plan. Then, in 
accordance with State law, on July 10, 2008, ADEQ adopted and submitted 
the 2008 CO Maintenance Plan to EPA as a revision to the Arizona SIP. 
The process followed by PAG and ADEQ in adopting the 2008 CO 
Maintenance Plan complies with the procedural requirements for SIP 
revisions under CAA section 110 and EPA's implementing regulations.
    Documentation in ADEQ's June 22, 2009 SIP submittal shows that 
appropriate notice, hearing, and adoption procedures were also followed 
by PAG and ADEQ with regards to the adoption and submittal of the SIP 
revision containing the statutory provision (ARS section 41-3017.01) 
that extends the life of the VEI program through the end of 2016.

B. Substantive Requirements

    EPA has reviewed the 2008 CO Maintenance Plan, which provides the 
second 10-year update to the CO maintenance plan for the TAPA, as 
required under CAA section 175A(b). The following is a summary of the

[[Page 39010]]

requirements and EPA's evaluation of how each requirement is met.
1. Attainment Emissions Inventory
    For maintenance plans, a State should develop a comprehensive, 
accurate inventory of actual emissions for an attainment year to 
identify the level of emissions which is sufficient to maintain the 
NAAQS. A State should develop this inventory consistent with EPA's most 
recent guidance on emissions inventory development. For CO, the 
inventory should reflect typical wintertime conditions.
    The 2008 CO Maintenance Plan includes a CO attainment inventory for 
the TAPA that reflects typical wintertime conditions in year 2008. 
Table 1 presents a summary of the inventory for 2008 contained in the 
maintenance plan. As shown in table 1, the 2008 Maintenance Plan 
estimates that on-road mobile sources contribute approximately 63% to 
the total CO inventory within the TAPA in 2008 and nonroad mobile 
contribute approximately 33%. Stationary point and area sources 
contribute less than 4%.

   Table 1--2008 Typical Winter Day CO Emissions for the Tucson Region
                               (tons/day)
------------------------------------------------------------------------
                                                            Percent of
                 Sources                  CO  (tons/day)     total CO
                                                             emissions
------------------------------------------------------------------------
Point...................................            9.04            1.66
Area....................................            9.57            1.75
Nonroad Mobile..........................          182.62           33.46
On-road Mobile..........................          344.56           63.13
                                         -----------------
    TOTAL...............................          545.79
------------------------------------------------------------------------
Source: 2008 CO Maintenance Plan, page 6.

    Appendix A of the 2008 CO Maintenance Plan describes the methods, 
models, and assumptions used to develop the attainment inventory. As 
described in appendix A, for stationary point and area sources, PAG 
generally relied upon the results of a 2001 study of actual emissions 
in 2000 to project emissions from such sources in 2008. However, with 
respect to one particular area source, residential wood burning, PAG 
updated the baseline estimates to reflect more accurate activity level 
estimates. Nonroad mobile source emissions were, in part, estimated 
using EPA's NONROAD2005 emission model (agricultural, commercial and 
mining, industrial and recreational equipment, and commercial and 
residential lawn and garden equipment). For on-road mobile sources, PAG 
used the latest EPA motor vehicle emissions model, MOBILE6.2, and the 
latest planning assumptions regarding vehicle type, vehicle activity, 
and vehicle speeds to estimate vehicular emissions for 2008. PAG's 
estimates for vehicles reflect 2007 winter meteorological conditions, 
local wintertime gasoline specifications, such as minimum oxygen 
content, the State's VEI program, and the averaging of high-altitude 
and low-altitude MOBILE6.2 emissions factors.
    Based on our review of the methods, models, and assumptions used by 
PAG to develop the CO estimates, we find that the 2008 Maintenance Plan 
includes a comprehensive, reasonably accurate inventory of actual CO 
emissions in an attainment year (2008), and conclude that the plan's 
inventory is acceptable for the purposes of a subsequent maintenance 
plan under CAA section 175A(b).
2. Maintenance Demonstration
    The maintenance plan demonstration requirement is considered to be 
satisfied for areas that were once nonclassifiable for CO (e.g., TAPA) 
if the monitoring data show that the area is meeting the air quality 
criteria for limited maintenance areas (7.65 ppm or 85 percent of the 
eight-hour CO NAAQS). PAG has opted to develop an LMP to fulfill the 
TAPA second 10-year maintenance period requirement under CAA section 
175A(b).
    Under the LMP option, there is no requirement to project emissions 
over the maintenance period. EPA believes if the area begins the first 
10-year maintenance period at or below 7.65 ppm, eight-hour average (85 
percent of the NAAQS), the air quality, along with the continued 
applicability of PSD requirements, any control measures already in the 
SIP, and Federal measures, should provide adequate assurance of 
maintenance over the initial 10-year maintenance period.
    The same holds true for the second 10-year maintenance period. If 
the area initially qualified for the LMP option, and the monitoring 
data over the first 10-year maintenance period continues to meet the 
air quality criteria for limited maintenance areas (7.65 ppm or 85 
percent of the NAAQS), then we believe that the air quality, along with 
the continued applicability of PSD requirements, any control measures 
already in the SIP, and Federal measures, should provide adequate 
assurance of maintenance over the second 10-year maintenance period.
    Table 2 presents the second highest 8-hour CO concentration at the 
six CO monitoring sites in the TAPA over the 1998-2008 period. Two of 
the six monitoring sites, the 22nd Street/Alvernon and Golf Links/Kolb 
sites, are considered microscale and record concentrations in the 
vicinities of heavily-traveled intersections. As shown in table 2, 2nd-
high CO concentrations, which form the basis for the design value in an 
area, have all been well below the LMP option threshold of 7.65 ppm at 
all of the monitoring stations over the entire first 10-year 
maintenance period. (The current design value is 2.0 ppm based on 2006-
2008 data.) Moreover, the 2008

[[Page 39011]]

CO Maintenance Plan essentially maintains existing controls, including 
the FMVCP, the State's VEI program,\4\ the wintertime oxygenated 
gasoline program, and contingency provisions.
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    \4\ The State's VEI program, as approved in the Arizona SIP, is 
authorized through the end of 2008. In 2007, the State Legislature 
acted to extend the program through the end of 2016 (see ARS section 
41-3017.01). As noted above, on June 22, 2009, ADEQ submitted ARS 
41-3017.01 to EPA as a SIP revision, and we are proposing to approve 
the VEI program extension in this notice. We recognize that 2016 is 
3\1/2\ years short of the end of the second 10-year maintenance 
period. However, in a letter dated March 10, 2008, and included as 
appendix D of the 2008 CO Maintenance Plan, ADEQ explains why it 
believes that the VEI program will continue beyond 2016 
nothwithstanding the sunset date. First, ADEQ states that the VEI 
program is recognized as an integral component for air quality plans 
in both the Phoenix and Tucson areas and that continuation of the 
program is important to achieve and maintain the NAAQS in those 
areas. Second, ADEQ notes that the Arizona Legislature has 
consistently supported the program since its inception in 1976, and 
thus, can reasonably be expected to do so in the future. EPA 
believes that ADEQ's rationale provides a reasonable basis for EPA 
to assume that the VEI program will be extended when it expires at 
the end of 2016.

Table 2--Second Highest Eight-Hour CO Concentrations (ppm) at the Six CO Monitoring Sites in the TAPA, 1998-2008
----------------------------------------------------------------------------------------------------------------
                                                    22nd/        22nd/      Children's    Cherry/    Golf Links/
               Year                   Downtown    Craycroft     Alvernon       Park        Glenn         Kolb
----------------------------------------------------------------------------------------------------------------
1998..............................          3.9          2.3          4.0          1.7          3.1           ND
1999..............................          3.2          2.0          3.8          1.9          3.4           ND
2000..............................          3.5          2.4          4.7          1.9          3.3           ND
2001..............................          2.5          1.7          2.9          1.7          2.6           ND
2002..............................          2.3          1.9          2.5          1.6          2.3          2.6
2003..............................          2.7          1.9          2.6          1.4          2.7          2.2
2004..............................          2.5          1.6          2.0          1.4          2.2          2.1
2005..............................          1.7          1.5          2.1          1.1          2.4          2.1
2006..............................          1.2          1.4          1.8          1.0          2.0          1.6
2007..............................          1.4          1.2          1.9          1.0          1.5          1.3
2008..............................          1.0          1.1          1.3          0.9          1.5          1.2
----------------------------------------------------------------------------------------------------------------
Source: Air Quality System, Quick Look Summary Report, March 17, 2009.

    Therefore, the TAPA continues to be eligible for the LMP option, 
and the long record of low monitored CO concentrations, together with 
the continuation of existing CO emissions control programs, adequately 
demonstrate that the TAPA will maintain the CO NAAQS through the second 
10-year maintenance period and beyond.
3. Monitoring Network and Verification of Continued Attainment
    EPA reviews the CO monitoring network that PDEQ operates and 
maintains, in accordance with 40 CFR part 58. This network is 
consistent with the ambient air monitoring network assessment and plan 
developed by PDEQ that is submitted annually to EPA and that follows a 
public notification and review process. EPA has reviewed and approved 
the 2007 Ambient Air Monitoring Network Assessment and Plan (``2007 
Annual Network Plan'').\5\
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    \5\ See EPA letter dated November 10, 2008, to Ursula Kramer, 
PDEQ, from Sean Hogan, EPA Region 9, in the docket for today's 
action.
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    To verify the attainment status of the area over the maintenance 
period, the maintenance plan should contain provisions for continued 
operation of an appropriate, EPA-approved monitoring network in 
accordance with 40 CFR part 58. As noted above, PDEQ's monitoring 
network in the TAPA has been approved by EPA in accordance with 40 CFR 
part 58, and the area has committed to continue to maintain a network 
in accordance with EPA requirements. For further details on monitoring, 
the reader is referred to the 2007 PDEQ Annual Network Plan found at: 
http://www.pima.gov/deq/air/pdf/2007NetworkReview.pdf as well as EPA's 
approval letter for the 2007 Annual Network Plan, which can be found in 
the docket for today's action. We believe PDEQ's monitoring network is 
adequate to verify continued attainment of the CO NAAQS in the TAPA.
4. Contingency Plan
    Section 175A(d) of the Act requires that a maintenance plan include 
contingency provisions. The purpose of such contingency provisions is 
to prevent future violations of the NAAQS or promptly remedy any NAAQS 
violations that might occur during the maintenance period.
    The 2008 CO Maintenance Plan carries forward the same contingency 
provisions, only slightly modified, that were included in the 1996 CO 
Maintenance Plan, and that we found acceptable when we approved the 
earlier maintenance plan. In short, and much like the 1996 CO 
Maintenance Plan, the 2008 CO Maintenance Plan identifies events, 
including measurements of certain threshold CO concentrations or 
projections of high CO concentrations based on periodic modeling 
analyses, that trigger a requirement to conduct specific types of field 
studies and technical analyses, followed by adoption and implementation 
of contingency measures as needed to address the sources causing the 
elevated CO conditions. The 2008 CO Maintenance Plan lists potential 
contingency measures such as transportation system management 
improvements and incremental increases in the wintertime gasoline 
oxygen content, among others.
    The only significant difference between the contingency provisions 
in the approved 1996 CO Maintenance Plan and the contingency provisions 
in the submitted 2008 CO Maintenance Plan relates to the use of a 
portable CO monitor. In the 1996 plan, the use of a portable CO monitor 
was not made contingent upon the occurrence of a particular event, but 
rather was a part of ongoing monitoring and modeling efforts to verify 
continued attainment. In contrast, the 2008 CO Maintenance Plan commits 
to the use of a portable CO monitor contingent upon the occurrence of 
certain monitored levels or a determination by PAG that the agency's 
periodic modeling analyses have raised a reasonable probability of CO 
violations at hot-spot locations within the TAPA. In view of the low 
monitored CO levels in the TAPA, we find acceptable the reduced role 
for the portable CO monitor, and believe that the contingency 
provisions in the 2008

[[Page 39012]]

CO Maintenance Plan meet the requirements of CAA section 175A(d).

C. Conclusion

    We conclude that the 2008 CO Maintenance Plan, as supplemented by 
the submittal of the statutory provision extending the VEI program, 
includes an acceptable update of the various elements of the initial 
EPA-approved 1996 CO Maintenance Plan (including emissions inventory, 
assurance of adequate monitoring and verification of continued 
attainment, and contingency provisions), and essentially carries 
forward all of the control measures and contingency provisions relied 
upon in the earlier plan. We also find that the TAPA, a former 
nonclassifiable CO nonattainment area, continues to qualify for the LMP 
option and that therefore the 2008 CO Maintenance Plan adequately 
demonstrates maintenance of the CO NAAQS through the documentation of 
monitoring data showing maximum CO levels less than 7.65 ppm, eight-
hour average (85 percent of the NAAQS), and through the continuation of 
existing control measures. We believe the 2008 CO Maintenance Plan as 
supplemented, to be sufficient to provide for maintenance of the CO 
NAAQS in the TAPA over the second 10-year maintenance period (i.e., 
through mid-2020) and thereby satisfy the requirements for such a plan 
under CAA section 175A(b). In light of the above, we are therefore 
proposing to approve ADEQ's submittal on July 10, 2008 of the 2008 CO 
Maintenance Plan, and ADEQ's submittal on June 22, 2009 of the 
statutory provision extending the life of the VEI program, as a 
revision to the Arizona SIP.

V. Transportation and General Conformity

    Section 176(c) of the Act requires that all Federal actions conform 
to an applicable SIP. Conformity is defined in section 176(c) of the 
Act as conformity to a SIP's purpose of eliminating or reducing the 
severity and number of violations of the NAAQS and achieving 
expeditious attainment of such standards, and that such activities will 
not: (1) Cause or contribute to any new violation of any standard in 
any area; (2) increase the frequency or severity of any existing 
violation of any standard in any area; or (3) delay timely attainment 
of any standard or any required interim emission reductions or other 
milestones in any area. EPA has established criteria and procedures for 
Federal agencies to follow in determining conformity of their actions. 
EPA's rule governing transportation plans, programs, and projects 
approved or funded by the Federal Highway Administration or Federal 
Transit Administration is referred to as the ``transportation 
conformity'' rule (see 40 CFR part 93, subpart A), and EPA's rule 
governing all other types of Federal agency actions is referred to as 
the ``general conformity'' rule (see 40 CFR part 93, subpart B).
    The transportation conformity rule and the general conformity rule 
apply to nonattainment areas and former nonattainment areas, like TAPA, 
that have been redesignated as attainment and that are subject to a 
maintenance plan. Under either rule, one means of demonstrating 
conformity of Federal actions is to indicate that expected emissions 
from planned actions are consistent with the emissions budget for the 
area.
    While EPA's LMP option does not exempt an area from the need to 
affirm conformity, it explains that the area may demonstrate conformity 
without submitting an emissions budget. Under the LMP option, emissions 
budgets are treated as essentially not constraining for the length of 
the applicable maintenance period because it is unreasonable to expect 
that such an area will experience so much growth in that period that a 
violation of the CO NAAQS would result. In other words, in LMP areas, 
EPA concludes that emissions need not be capped for the maintenance 
period. Therefore, in areas with approved LMPs, Federal actions 
requiring conformity determinations under the transportation conformity 
rule are considered to satisfy the ``budget test'' required in 40 CFR 
93.118. Similarly, in these areas, Federal actions subject to the 
general conformity rule are considered to satisfy the ``budget test'' 
specified in 40 CFR 93.158(a)(5)(i)(A) of the rule.
    While areas with maintenance plans approved under the LMP option 
are not subject to the budget test, the areas remain subject to other 
transportation conformity requirements of 40 CFR part 93, subpart A. 
Thus, the applicable MPO or State must document and ensure that:
    (a) Transportation plans and projects provide for timely 
implementation of SIP transportation control measures in accordance 
with 40 CFR 93.113;
    (b) Transportation plans and projects comply with the fiscal 
constraint element per 40 CFR 93.108;
    (c) The MPO's interagency consultation procedures meet the 
applicable requirements of 40 CFR 93.105;
    (d) Conformity of transportation plans is determined no less 
frequently than every four years, and conformity of plan amendments and 
transportation projects is demonstrated in accordance with the timing 
requirements specified in 40 CFR 93.104;
    (e) The latest planning assumptions and emissions model are used as 
set forth in 40 CFR 93.110 and 40 CFR 93.111;
    (f) Projects do not cause or contribute to any new localized CO 
violations, in accordance with procedures specified in 40 CFR 93.123; 
and
    (g) Project sponsors and/or operators provide written commitments 
as specified in 40 CFR 93.125.
    We posted the 2008 Revision to the Carbon Monoxide Limited 
Maintenance Plan for the Tucson Air Planning Area on EPA's 
transportation conformity adequacy Web site on October 2, 2008 for 30 
days and did not receive any comments on the adequacy of the plan. We 
believe that the 2008 CO Maintenance Plan demonstrates that it is 
unreasonable to expect that the area would experience enough growth in 
motor vehicle emissions for a violation of the CO NAAQS to occur and 
qualifies as an LMP, and on that basis, we are proposing to approve the 
2008 CO Maintenance Plan for transportation conformity purposes. This 
determination waives the need for a motor vehicle emissions budget, 
although it does not relieve the area or the other transportation 
conformity requirements noted above. If finalized as proposed, PAG (the 
area's MPO), the Federal Highway Administration, and the Federal 
Transit Administration will not be required to satisfy the regional 
emissions analysis (with respect to CO) under 40 CFR 93.118 and/or 40 
CFR 93.119 in determining the conformity of transportation plans, 
programs and projects in the TAPA. See 40 CFR 93.109(j).

VI. Proposed Action and Public Comment

    Under sections 110(k) and 175A of the CAA and for the reasons set 
forth above, EPA is proposing to approve two revisions of the Arizona 
SIP submitted by ADEQ. The first, submitted on July 10, 2008, includes 
the 2008 CO Maintenance Plan for the Tucson Air Planning Area, and the 
second, submitted on June 22, 2009, includes a statutory provision (ARS 
section 41-3017.01) extending the life of the VEI program through the 
end of 2016.
    We are proposing to approve the 2008 CO Maintenance Plan because we 
find that it includes an acceptable update of the various elements of 
the initial EPA-approved 1996 CO Maintenance Plan (including emissions 
inventory, assurance of adequate monitoring and verification of 
continued attainment,

[[Page 39013]]

and contingency provisions), and essentially carries forward all of the 
control measures and contingency provisions relied upon in the earlier 
plan. We also find that the TAPA, a former nonclassifiable CO 
nonattainment area, continues to qualify for the LMP option and that 
therefore the 2008 CO Maintenance Plan adequately demonstrates 
maintenance of the CO NAAQS through documentation of monitoring data 
showing maximum CO levels less than 85% of the NAAQS and continuation 
of existing control measures. We believe the 2008 CO Maintenance Plan 
to be sufficient to provide for maintenance of the CO NAAQS in the TAPA 
over the second 10-year maintenance period and to thereby satisfy the 
requirements for such a plan under CAA section 175A(b). If finalized as 
proposed, our approval will make Federally enforceable the 2008 CO 
Maintenance Plan's contingency provisions, which are slightly modified 
from the corresponding provisions in the 1996 CO Maintenance Plan.
    In connection with the 2008 CO Maintenance Plan, we are proposing 
to approve the statutory provision, ARS section 41-3017.01, that 
extends the life of the State's VEI program (applicable to the TAPA and 
Phoenix metropolitan areas) until the end of 2016, and that was 
submitted to EPA as a revision to the Arizona SIP on June 22, 2009, 
based on our expectation that the Arizona Legislature will extend the 
VEI program beyond 2016.
    We also find that the 2008 CO Maintenance Plan qualifies for 
evaluation as an limited maintenance plan under our LMP policy in light 
of low monitored CO levels in the TAPA and therefore propose to approve 
the 2008 CO Maintenance Plan for transportation conformity purposes. If 
finalized as proposed, PAG (the area's MPO), the Federal Highway 
Administration, and the Federal Transit Administration will not be 
required to satisfy the regional emissions analysis under 40 CFR 93.118 
and/or 40 CFR 93.119 in determining conformity of transportation plans 
and programs in the TAPA.
    EPA is soliciting public comments on this document and on issues 
relevant to EPA's proposed action. We will accept comments from the 
public on this proposal for the next 30 days.

VII. Statutory and Executive Order Reviews

    Under the Clean Air Act, the Administrator is required to approve a 
SIP submission that complies with the provisions of the Act and 
applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). 
Thus, in reviewing SIP submissions, EPA's role is to approve State 
choices, provided that they meet the criteria of the Clean Air Act. 
Accordingly, this action proposes to approve State law as meeting 
Federal requirements and does not impose additional requirements beyond 
those imposed by State law. For that reason, this proposed action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Order 
12866 (58 FR 51735, October 4, 1993);
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of Section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the Clean Air Act; and
     Does not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, this proposed rule does not have Tribal implications 
as specified by Executive Order 13175 (65 FR 67249, November 9, 2000), 
because the SIP is not approved to apply in Indian country located in 
the State, and EPA notes that it will not impose substantial direct 
costs on Tribal governments or preempt Tribal law.

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Carbon monoxide, 
Intergovernmental relations, Reporting and recordkeeping requirements.

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

    Dated: July 21, 2009.
Kathleen H. Johnson,
Acting Regional Administrator, Region IX.
[FR Doc. E9-18693 Filed 8-4-09; 8:45 am]

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