[Federal Register Volume 70, Number 13 (Friday, January 21, 2005)]
[Proposed Rules]
[Pages 3174-3178]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-1119]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 81

[FRL-7862-5]


Determination of Attainment by the Applicable Attainment Date for 
the Carbon Monoxide National Ambient Air Quality Standard Within the 
Las Vegas Valley Nonattainment Area, Clark County, NV; Determination 
Regarding Applicability of Certain Clean Air Act Requirements

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing to find that the Las Vegas Valley 
nonattainment area in the State of Nevada has attained the National 
Ambient Air Quality Standard for carbon monoxide by the applicable 
December 31, 2000 attainment date. Based on this proposal, EPA also 
proposes to determine that the Clean Air Act's requirements for 
contingency provisions will no longer apply to the area.

DATES: Written comments on this proposal must be received by February 
22, 2005.

ADDRESSES: Comments should be addressed to the EPA contact below. You 
may inspect and copy the rulemaking docket for this notice at the 
following location during normal business hours. We may charge you a 
reasonable fee for copying parts of the docket. Steven Barhite, Chief, 
Environmental Protection Agency, Region IX, Air Division, Air Planning 
Office (AIR-2), 75 Hawthorne Street, San Francisco, CA 94105-3901.

FOR FURTHER INFORMATION CONTACT: Karina O'Connor, Air Planning Office 
(AIR-2), Air Division, U.S. EPA, Region IX, 75 Hawthorne Street, San 
Francisco, CA 94105-3901. Telephone: (775) 833-1276. E-mail: 
[email protected].

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

Table of Contents

I. Attainment Finding
    A. Background
    1. Which NAAQS is considered in today's proposed finding?
    2. What is the designation and classification of this CO 
nonattainment area?
    3. How do we make attainment determinations?
    B. Basis for EPA's Proposed Attainment Finding
    1. What is the statutory basis for this proposed finding?
    2. How did we determine that Las Vegas Valley has attained the 
CO NAAQS by the applicable attainment date?
II. Applicability of Clean Air Act Contingency Provisions
    A. Background
    B. Effect of a Finding of Attainment by Applicable Attainment 
Date on CAA Contingency Measure Requirement
III. EPA's Proposed Action
IV. Request for Public Comment
V. Administrative Requirements

I. Attainment Finding

A. Background

1. Which NAAQS Is Considered in Today's Proposed Finding?
    Carbon monoxide (CO) is a colorless, odorless gas emitted in 
combustion processes. In most areas where elevated CO levels are found, 
CO comes primarily from tailpipe emissions of cars and trucks. Exposure 
to elevated CO levels is associated with impairment of visual 
perception, work capacity, manual dexterity, and learning ability, and 
with illness and death for those who already suffer from cardiovascular 
disease, particularly angina or peripheral vascular disease.
    On April 30, 1971 (see 36 FR 8186), pursuant to section 109 of the 
Clean Air Act (CAA or ``Act''), as amended in 1970, we promulgated the 
original National Ambient Air Quality Standards (NAAQS) for several 
pervasive air pollutants, including CO. NAAQS represent concentration 
levels the attainment and maintenance of which, allowing for an 
adequate margin of safety, EPA has determined to be requisite to 
protect public health (``primary'' NAAQS) and welfare (``secondary'' 
NAAQS). The primary (i.e., health-based) NAAQS for CO is 9 parts per 
million (ppm) averaged over an 8-hour period, and 35 ppm averaged over 
1 hour, neither to be exceeded more than once per year. In our 1971 
rulemaking, we established identical primary and secondary NAAQS for CO 
but later revoked the secondary (welfare) NAAQS for CO. See 50 FR 37484 
(September 13, 1985).
2. What Is the Designation and Classification of This CO Nonattainment 
Area?
    As noted above, EPA first promulgated the NAAQS in 1971, and within 
9 months thereafter, each State was required under section 110 of the 
Act to adopt and submit to EPA a plan that provides for the 
implementation, maintenance, and enforcement of the NAAQS within each 
State. These plans are referred to as ``State implementation plans'' or 
``SIPs.'' Generally, SIPs were to provide for attainment of the NAAQS 
within 3 years after EPA approval of the plan. However, many areas of 
the country did not attain the NAAQS within the statutory period. In 
response, Congress amended the Act in 1977 to establish a new approach, 
based on area designations, for attaining the NAAQS, and on March 3, 
1978 (see 43 FR 8962), we promulgated attainment status designations 
for all areas within each of the States. In this 1978 rulemaking, we 
designated Las Vegas Valley (i.e., State hydrographic area 
212), which is a subarea within Clark County, as a 
``nonattainment'' area for the CO NAAQS.
    The Clean Air Act, as amended in 1977, required States to revise 
their SIPs by preparing, adopting and submitting attainment plans (for 
EPA approval) that set forth a strategy to achieve the NAAQS in 
designated nonattainment areas. The original statutory deadline for 
attainment was 1982. EPA conditionally approved the initial CO 
attainment plan for Las Vegas Valley into the Nevada SIP in 1981. See 
46 FR 21758 (April 14, 1981). EPA removed the conditions on the CO plan 
in 1982. See 47 FR 15790 (April 13, 1982). Updated attainment plans 
were required for areas, like Las Vegas Valley, that did not achieve 
the original 1982 deadline. EPA approved an updated plan for CO in Las 
Vegas Valley into the Nevada SIP in 1984. See 49 FR 44208 (November 5, 
1984).

[[Page 3175]]

    Notwithstanding our approval of the updated CO attainment plan that 
was intended to provide for attainment in the valley by the end of 
1987, the CO NAAQS was not actually attained by the end of that year in 
Las Vegas Valley, nor was it attained in many other areas of the 
country. In 1988, EPA notified the Governors of the various States in 
which areas had failed to attain the CO NAAQS that their SIPs were 
inadequate and that their SIPs must be revised (``SIP call''). See 53 
FR 34500 (September 7, 1988). The SIP call involved a two-phase 
approach. The first phase called for the States to fix deficiencies in 
their existing plans and to implement any measures already adopted but 
not yet implemented. The second phase, which called for development of 
a new attainment plan, awaited Congressional amendments to the Clean 
Air Act that were anticipated to occur in 1990. See 55 FR 30873 (July 
30, 1990).
    As anticipated, the Act was substantially amended in 1990 to 
establish new planning requirements and attainment deadlines for the 
NAAQS. Under section 107(d)(1)(C) of the Act, areas designated 
nonattainment at the time of enactment of the 1990 Act Amendments, 
including Las Vegas Valley, were designated nonattainment by operation 
of law. Under section 186(a) of the Act, each CO area designated 
nonattainment under section 107(d) was also classified by operation of 
law as either moderate or serious, depending on the severity of the 
area's air quality problem. CO areas with design values between 9.1 and 
16.4 parts per million (ppm), such as the Las Vegas Valley area, were 
classified as moderate. See 56 FR 56694 (November 6, 1991). (The design 
value for Las Vegas Valley for initial classification purposes was 14.4 
ppm, which was based on monitoring data from the late 1980's.)
    Section 172 of the 1990 Act Amendments contains general 
requirements applicable to SIP revisions for nonattainment areas, and 
sections 186 and 187 set out additional air quality planning 
requirements for CO nonattainment areas. The most fundamental of these 
provisions is the requirement that CO nonattainment areas with design 
values greater than 12.7 ppm submit a SIP revision demonstrating 
attainment of the NAAQS as expeditiously as practicable but no later 
than the deadline applicable to the area's classification: December 31, 
1995, for moderate areas. See CAA sections 186(a)(1) and 187(a)(7).
    Las Vegas Valley failed to reach attainment by December 31, 1995, 
but, under section 186(a)(4) of the Act, the State of Nevada requested, 
and EPA granted, a one-year extension of the attainment date, i.e., to 
December 31, 1996. See 61 FR 57331 (November 6, 1996). However, in the 
first quarter of 1996, three exceedances of the CO standard were 
recorded at the East Charleston monitoring station in Las Vegas, and 
thus, the State was unable to show attainment of the standard by 
December 31, 1996 and could not qualify for an additional one-year 
extension under section 186(a)(4) of the Act.
    Subsequently, on October 2, 1997, we published a final rule that 
found that the Las Vegas Valley CO nonattainment area did not attain 
the CO NAAQS by the applicable attainment date and that reclassified 
the area from ``moderate'' to ``serious'' nonattainment under section 
186(b)(2) of the Act. See 62 FR 51604 (October 2, 1997). Areas 
reclassified as serious are given more time to develop a new attainment 
plan and a new attainment date but are subject to additional 
requirements beyond those that are required in moderate nonattainment 
areas. For Las Vegas Valley, the effect of the reclassification to 
``serious'' was to allow Nevada 18 months from the effective date of 
the reclassification to submit a new plan demonstrating attainment of 
the CO NAAQS as expeditiously as practicable but no later than December 
31, 2000, the CAA attainment date for serious CO nonattainment areas.
    In 2000, the State of Nevada submitted a new plan that revises the 
CO attainment strategy and that provides a demonstration of attainment, 
based on modeling techniques, by the new attainment deadline, i.e., 
December 31, 2000. In January 2003, EPA proposed to approve the various 
plan elements contained in this latest CO plan, including the modeled 
attainment demonstration. See 68 FR 4141 (January 28, 2003). In 
September 2004, we finalized our approval of all of the plan elements 
except for the contingency provisions. See 69 FR 56351 (September 21, 
2004).
3. How Do We Make Attainment Determinations?
    Section 179(c)(1) of the Act provides that attainment 
determinations are to be based on the ``area's air quality as of the 
attainment date,'' and section 186(b)(2) of the Act is consistent with 
this requirement but adds that CO air quality is to be documented for 
attainment determination purposes in terms of ``design values''. EPA 
makes the determination as to whether an area's air quality is meeting 
the CO NAAQS based upon air quality data gathered at CO monitoring 
sites in the nonattainment area which have been entered into the Air 
Quality System (AQS) database, formerly known as the Aerometric 
Information Retrieval System (AIRS). This data is reviewed to determine 
the area's air quality status in accordance with 40 CFR 50.8, EPA 
policy guidance as stated in a memorandum from William G. Laxton, 
Director Technical Support Division, entitled ``Ozone and Carbon 
Monoxide Design Value Calculations,'' dated June 18, 1990, and in EPA's 
``General Preamble for the Implementation of Title I of the Clean Air 
Act Amendments of 1990'' (see 57 FR 13498, at 13535, April 16, 1992).
    The 8-hour and 1-hour CO design values are used to determine 
attainment of CO areas, and the design values are determined by 
reviewing 8 quarters of data, or a total of 2 complete calendar years 
of data for an area. The 8-hour design value is computed by first 
finding the maximum and second maximum (non-overlapping) 8-hour values 
at each monitoring site for each year of the two calendar years prior 
to and including the attainment date. Then the higher of the two 
``second high'' values is used as the design value for the monitoring 
site, and the highest design value among the various CO monitoring 
sites represents the CO design value for the area.
    The CO NAAQS requires that not more than one 8-hour average per 
year can equal or exceed 9.5 ppm (values below 9.5 are rounded down to 
9 and are not considered exceedances). If an area has a design value 
that is equal to or greater than 9.5 ppm, this means that there was a 
monitoring site where the second highest (non-overlapping) 8-hour 
average was measured to be equal to or greater than 9.5 ppm in at least 
1 of the 2 years being reviewed to determine attainment for the area. 
This indicates that there were at least two values above the NAAQS 
during 1 year at that site and thus the NAAQS for CO was not met. 
Conversely, an eight-hour design value of less than 9.5 ppm indicates 
that the area has attained the CO NAAQS. The one-hour CO design value 
is computed in the same manner.

B. Basis for EPA's Proposed Attainment Finding

1. What Is the Statutory Basis for This Proposed Finding?
    Pursuant to sections 179(c)(1) and 186(b)(2) of the Act, we have 
the responsibility of determining within six months of the applicable 
attainment date whether, based on the area's design

[[Page 3176]]

value as of the attainment date, the CO nonattainment area attained the 
NAAQS by that date. As a CO nonattainment area that was reclassified as 
``serious'' under 186(b)(2)(A) of the Act, Las Vegas Valley was 
required under section 186 of the Act to attain the CO NAAQS no later 
than December 31, 2000. Therefore, our obligation, under sections 
179(c)(1) and 186(b)(2) of the Act, is to determine whether the Las 
Vegas Valley attained the CO NAAQS based on the area's design value as 
of December 31, 2000.
2. How Did We Determine That Las Vegas Valley Has Attained the CO NAAQS 
by the Applicable Attainment Date?
    As additional background, we provide a brief description in the 
following paragraphs of the Las Vegas Valley CO nonattainment area and 
CO monitoring network before discussing the monitoring data that 
provide the basis for determining the design value and attainment of 
the CO NAAQS.
    Characteristics of Nonattainment Area: The population of the Las 
Vegas Valley nonattainment area (State hydrographic area 212) 
is approximately 1.4 million residents. The valley, located in southern 
Nevada, lies entirely within Clark County and includes the cities of 
Las Vegas, North Las Vegas, and Henderson. The remainder of the 
nonattainment area includes unincorporated areas of Clark County. The 
nonattainment area, approximately 1,500 square miles, is bounded by the 
Spring Mountains to the west, the Pintwater, Desert, Sheep, and Las 
Vegas Mountains to the north, and Frenchman Mountain to the east. The 
McCullough Range and Big Spring Range close the area to the south.
    Valley drainage flows to the south, toward the McCullough and Big 
Spring Ranges, then easterly through the Las Vegas Wash to Lake Mead. 
Las Vegas Valley's climate, at the edge of the Mojave Desert, is very 
dry and warm. Average annual precipitation is 4.2 inches. Temperatures 
through a year can range from daily maximums in July of 104 degrees 
Fahrenheit to average daily minimums in January of 33 degrees 
Fahrenheit. Climatic conditions, and Las Vegas' location in a broad 
valley, result in calm wind conditions during the winter. These low 
winds combine with temperature inversions and nighttime downslope 
drainage of air back into the valley, preventing effective dispersion 
of air pollutants.
    CO Monitoring Network: EPA has established ambient air quality 
monitoring requirements and standards for State and Local Air 
Monitoring Stations (SLAMS) and for National Air Monitoring Stations 
(NAMS). These requirements and standards provide for operating 
schedules, data quality assurance, and for the design and siting of CO 
samplers.
    The Clark County Health District began monitoring CO in Las Vegas 
Valley in the early 1970's and operated continuous CO monitors at two 
locations (East Charleston and Casino Center Blvd.) by the mid-1970's. 
Since then, the CO ambient monitoring network in Las Vegas Valley has 
evolved into a system of 15 monitoring sites. All of these stations are 
operated by the Clark County Department of Air Quality and 
Environmental Management (DAQEM), which is the local agency now 
responsible for the ambient air monitoring (and other regulatory) 
functions that had been conducted (i.e., until mid-2001) by the Clark 
County Health District. Currently, for CO, DAQEM operates 7 SLAMS 
sites, 4 NAMS sites, and 4 special purpose monitoring sites. Each of 
these air quality monitoring stations uses a Dasibi CO Analyzer which 
employs the Gas Filter Correlation technique. The monitoring schedule 
for CO is continuous. Most of the CO monitoring sites are sited at the 
neighborhood scale with an objective of assessing population exposure. 
The South Las Vegas Boulevard station, located near an intersection 
with high traffic density, is designated as microscale.
    In August 2001, EPA conducted a technical systems audit on DAQEM's 
ambient air monitoring program to assess its compliance with 
established regulations governing the collection, analysis, validation, 
and reporting of ambient air quality data. In our February 2002 report 
containing the findings of this audit, we concluded that, despite 
various program deficiencies, the data was suitable for use in 
regulatory decisions in light of substantial compliance with many of 
the quality control activities required by EPA regulations. Thus, we 
conclude that the CO data is appropriate for use in determining whether 
the Las Vegas Valley has attained the CO NAAQS. Our February 2002 audit 
report is included in the docket for this rulemaking.
    CO Monitoring Data: The following table summarizes the CO data 
collected at the various CO monitoring stations in Las Vegas Valley in 
1999 and 2000 and included in AQS.

          Summary of Carbon Monoxide Air Quality Data Las Vegas Valley, Clark County, Nevada, 1999-2000
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                                       2nd highest 8-hour concentration       2nd highest 1-hour concentration
                                                    (ppm)                                  (ppm)
   Monitoring site name and AQS    -----------------------------------------------------------------------------
              number                                             Design                                 Design
                                        1999         2000        value         1999         2000        value
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Boulder City (32-003-0601)........          0.6          1.1          1.1          1.1          1.3          1.3
City Center (32-003-0016).........          5.6          4.8          5.6          8.5          7.2          8.5
Craig Road (32-003-0020)..........          2.7          1.8          2.7          2.9          3.0          3.0
Crestwood (32-003-0562)...........          5.8          5.1          5.8          7.8          6.9          7.8
East Flamingo (32-003-1022).......          5.2          4.2          5.2          7.5          6.2          7.5
East Sahara (32-003-0539).........          6.9          5.7          6.9          8.7          7.2          8.7
Health District (32-003-0021).....          5.1          *ND          5.1          6.8          *ND          6.8
Green Valley (32-003-0298)........          1.9          1.7          1.9          3.0          2.7          3.0
S. East Valley (32-003-0007)......          1.7          1.5          1.7          3.3          2.8          3.3
Winterwood (32-003-0538)..........          6.5          4.1          6.5          8.3          6.0          8.3
Paul Meyer (32-003-0043)..........          2.0          1.6          2.0          2.8          3.0          3.0
Pittman (32-003-0107).............          2.5          2.1          2.5          5.9          4.2          5.9
S. Las Vegas Blvd (32-003-1023)...          4.4          3.7          4.4          6.9          5.6          6.9
Sunrise Acres (32-003-0561).......          8.2          7.1          8.2         10.2          8.5         10.2
J.D. Smith (32-003-2002)..........          4.4          3.8          4.4          6.7          5.8          6.7
                                   --------------
Area Design Value--Sunrise Acres..     8-Hour CO Design Value: 8.2 ppm
                                       1-Hour CO Design Value: 10.2 ppm
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Source: EPA Air Quality System (AQS) Database.
*ND = No Data.


[[Page 3177]]

    As shown in the above table, the design values are less than 9.5 
ppm (eight-hour average) and 35.5 ppm (one-hour average) at all of the 
sites. Therefore, we propose to find that the Las Vegas Valley attained 
the CO NAAQS by December 31, 2000, which is the applicable attainment 
date for this nonattainment area under the Act.
    A review of data input to AQS indicates that Las Vegas Valley has 
continued to attain the CO NAAQS since the end of 2000. The highest 8-
hour and 1-hour CO concentrations measured at the various monitoring 
stations during the 2001 through 2003 period were 7.2 ppm and 8.9 ppm, 
respectively (both at the Sunrise Acres station in 2001), which are 
well below the corresponding CO NAAQS of 9 ppm and 35 ppm, 
respectively. A ``quick look'' report generated using AQS for the Las 
Vegas Valley CO monitoring stations for the 2001 to 2003 period is 
included in the docket for this proposed rule.

II. Applicability of Clean Air Act Contingency Provisions

A. Background

    In our proposal to approve SIP revisions submitted by the State of 
Nevada to provide for attainment of the CO NAAQS in the Las Vegas 
Valley Nonattainment Area (68 FR 4141, January 28, 2003), we concluded 
that the contingency measure requirements for the area under sections 
172(c)(9) and 187(a)(3) of the Act were met by the implementation of 
standardized On-Board Diagnostics systems (OBD II) testing (as part of 
the vehicle inspection and maintenance (I/M) program). See 68 FR at 
4157. In that proposal, we also proposed to disapprove two other 
contingency measures (i.e., Lower I/M Program Cutpoints and On Road 
Remote Sensing) that had been submitted as part of the Las Vegas Valley 
serious area CO attainment plan, the Carbon Monoxide State 
Implementation Plan, Las Vegas Valley Nonattainment Area, Clark County, 
Nevada (August 2000). See 68 FR at 4157.
    In the final rule, we approved the SIP revisions as we had proposed 
with the exception of the contingency provisions. With respect to the 
contingency provisions, we stated that objections raised by public 
comments on the appropriateness of our proposed approval of OBD II 
testing as fulfilling the contingency measure requirements under 
sections 172(c)(9) and 187(a)(3) of the Act (in addition to fulfilling 
an I/M requirement) and the fact that Clark County had yet to provide 
quantitative information on the emissions reductions associated with 
OBD II testing consistent with their commitment to do so had lead us to 
defer taking final action on the contingency provisions in that notice. 
See 69 FR 56351 (September 21, 2004). We indicated in that final rule 
that we would address the contingency provision requirements for Las 
Vegas Valley in a separate rulemaking. This proposal constitutes that 
rulemaking.

B. Effect of a Finding of Attainment by Applicable Attainment Date on 
CAA Contingency Measure Requirement

    Upon our designation of Las Vegas Valley as a CO nonattainment 
area, Las Vegas Valley became subject to the contingency provisions set 
forth in subpart 1 (of title I of the Act) at section 172(c)(9) and in 
subpart 3 at section 187(a)(3). For the reasons described below, we 
believe that the contingency provisions under sections 172(c)(9) and 
187(a)(3) are no longer required for CO nonattainment areas that are 
determined to have attained the CO NAAQS by the applicable attainment 
date.
    Section 172(c)(9) requires a State to submit contingency measures 
that will be implemented if an area fails to make ``reasonable further 
progress'' (RFP) \1\ or fails to attain by the applicable attainment 
date. Thus, the stated purpose of the contingency measure requirement 
is to ensure RFP (the purpose of which is to ensure attainment by the 
applicable attainment date) and attainment by the applicable attainment 
date. If an area has in fact attained the standard by the applicable 
attainment date, the stated purpose of the contingency measure 
requirement will have already been fulfilled. Consequently, we believe 
that the requirement for a State to submit revisions providing for 
measures to meet the contingency provisions of section 172(c)(9) no 
longer applies for an area that we find as having attained the relevant 
NAAQS by the applicable attainment date. We note that we took this view 
with respect to the general contingency measure requirement of section 
172(c)(9) in our ``General Preamble for the Interpretation of Title I 
of the Clean Air Act Amendments of 1990'' at 57 FR 13498 (April 16, 
1992). In the General Preamble, we stated, in the context of a 
discussion of the requirements applicable to the evaluation of requests 
to redesignate nonattainment areas to attainment, that the ``section 
172(c)(9) requirements for contingency measures * * * no longer apply 
when an area has attained the standard and is eligible for 
redesignation.'' See 57 FR 13498, at 13564 (April 16, 1992). See also 
``Procedures for Processing Requests to Redesignate Areas to 
Attainment,'' from John Calcagni, Director, Air Quality Management 
Division, to Regional Air Division Directors, September 4, 1992 (http://www.epa.gov/ttn/naaqs/ozone/ozonetech/940904.pdf), at page 6.
---------------------------------------------------------------------------

    \1\ RFP means ``such annual incremental reductions in emissions 
of the relevant air pollutant as are required by this part or may 
reasonably be required by the Administrator for the purpose of 
ensuring attainment of the applicable national ambient air quality 
standard by the applicable date.'' See section 171(1) of the Act.
---------------------------------------------------------------------------

    Section 187(a)(3) identifies two circumstances for which 
contingency measures must be submitted. First, a State must submit 
contingency measures to be implemented if any estimate of vehicle miles 
traveled (VMT) in the area for any year prior to the attainment year 
that is submitted in an annual report under section 187(a)(2)(A) (``VMT 
tracking report'') exceeds the number predicted in the most recent 
prior forecast. This aspect of section 187(a)(3) supports reasonable 
further progress (RFP) by ensuring that the SIP contains a mechanism to 
correct for underprediction in the CO plan of VMT and related motor 
vehicle emissions in years prior to the attainment year, and thereby 
serves to help maintain the overall year-to-year reduction in CO 
emissions that is referred to as the RFP requirement. However, since 
the provision applies only to years prior to the attainment year and 
that year has already passed, and the purpose of RFP itself is 
fulfilled upon a finding of attainment by the applicable attainment 
date, we find that the additional support for RFP that would otherwise 
be provided through the application of section 187(a)(3) is no longer 
required upon that same finding of attainment by the applicable 
attainment date.
    Second, under section 187(a)(3) of the Act, a State must submit 
contingency measures to be implemented if the area fails to attain the 
national primary ambient air quality standard for carbon monoxide by 
the primary standard attainment date. This aspect of section 187(a)(3), 
i.e., failure to attain the CO NAAQS by the attainment date, 
essentially restates the requirement in section 172(c)(9) (``* * * 
measures to be undertaken if the area * * * fails to attain the 
national primary ambient air quality standard by the attainment date 
applicable under this part.'') As such, our interpretation of section 
172(c)(9) described above that a State need no longer submit revisions 
providing for measures to meet the contingency provisions of section 
172(c)(9) for areas that we find as having attained the CO NAAQS by the 
applicable attainment date applies equally to the

[[Page 3178]]

corresponding provision in section 187(a)(3).
    Therefore, based on our proposed finding that Las Vegas Valley has 
attained the CO NAAQS by the applicable attainment date (December 31, 
2000), we propose to find that the contingency requirements under 
section 172(c)(9) and 187(a)(3) of the Act will no longer apply for the 
Las Vegas Valley CO nonattainment area at such time as we finalize our 
proposed attainment finding.

III. EPA's Proposed Action

    EPA proposes to find, pursuant to sections 179(c)(1) and 186(b)(2) 
of the Act, that the Las Vegas Valley ``serious'' nonattainment area 
has attained the NAAQS for CO by the applicable attainment date. If 
finalized as proposed, our action will relieve the State of Nevada from 
the obligation under section 187(g) of the Act to prepare and submit a 
SIP revision providing for a reduction of CO emissions within Las Vegas 
Valley by at least five percent per year in each year after approval of 
the SIP revision until the CO NAAQS is attained. It should be noted 
that this proposed action does not represent a proposal to redesignate 
this area from ``nonattainment'' to ``attainment''. Under section 
107(d)(3)(E), the Clean Air Act requires that, for an area to be 
redesignated from nonattainment to attainment, five criteria must be 
satisfied including the submittal by the State (and approval by EPA) of 
a maintenance plan as a SIP revision. Therefore, the designation status 
of Las Vegas Valley in 40 CFR part 81 is unaffected by this proposed 
action, and Las Vegas Valley will remain a ``serious'' nonattainment 
area for CO until such time as EPA finds that the State of Nevada has 
met the Clean Air Act requirements for redesignation to attainment.
    Based on our proposed finding of attainment by the applicable 
attainment date, we are also proposing to determine that the CAA's 
requirement for the SIP to provide for CO contingency measures will no 
longer apply to Las Vegas Valley. In this instance, the State submitted 
contingency measures (as part of the Las Vegas Valley serious area CO 
plan adopted in August 2000), but we will continue to defer taking any 
further action on them under sections 172(c)(9) and 187(a)(3) of the 
Act in light of this proposed finding of attainment by the applicable 
attainment date and resulting determination that the contingency 
measure requirement no longer applies to the area. The State may elect 
to withdraw the contingency measures to lift the obligation on EPA 
under section 110(k) to act on SIP submittals within certain time 
periods. If we finalize this action as proposed, then the remaining FIP 
obligation (i.e., relative to contingency measures) that was triggered 
24 months after our finding of Nevada's failure to submit a serious 
area CO plan for Las Vegas Valley (see 64 FR 49084, September 10, 1999) 
will be permanently lifted.

IV. Request for Public Comment

    We are soliciting public comment on all aspects of this proposal. 
These comments will be considered before taking final action. To 
comment on today's proposal, you should submit comments by mail or in 
person (in triplicate if possible) to the ADDRESSES section listed in 
the front of this document. Your comments must be received by February 
22, 2005 to be considered in the final action taken by EPA.

V. Administrative Requirements

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), this 
proposed action is not a ``significant regulatory action'' and 
therefore is not subject to review by the Office of Management and 
Budget. For this reason, 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 
proposed action merely proposes to find that an area has attained a 
national ambient air quality standard based on an objective review of 
measured air quality data. It also proposes to determine that certain 
Clean Air Act requirements no longer apply so long as the area 
continues to attain the standard. If finalized, it would not impose any 
new regulations, mandates, or additional enforceable duties on any 
public, nongovernmental, or private entity. Accordingly, the 
Administrator certifies that this proposed 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 proposed rule does not impose any additional enforceable duty, it 
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).
    This proposed 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 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 proposes to find that an area has attained a national ambient 
air quality standard and is therefore not subject to certain specific 
requirements for so long as the area continues to attain the standard, 
and does not alter the relationship or the distribution of power and 
responsibilities established in the Clean Air Act. This proposed 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.
    This proposed rule does not involve establishment of technical 
standards, and thus, the requirements of section 12(d) of the National 
Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) do 
not apply. This proposed 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.)

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

List of Subjects in 40 CFR Part 81

    Environmental protection, Air pollution control, National parks, 
Wilderness areas.

    Dated: January 7, 2005.
Laura Yoshii,
Acting Regional Administrator, Region IX.
[FR Doc. 05-1119 Filed 1-19-05; 8:45 am]
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