Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality Planning Purposes; Arkansas; Redesignation of the Crittenden County, Arkansas Portion of the Memphis, Tennessee-Arkansas 1997 8-Hour Ozone Nonattainment Area to Attainment, 2091-2102 [2010-586]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 75, Number 9 (Thursday, January 14, 2010)]
[Proposed Rules]
[Pages 2091-2102]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-586]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R06-OAR-2009-0202; FRL-9103-2]


Approval and Promulgation of Implementation Plans and Designation 
of Areas for Air Quality Planning Purposes; Arkansas; Redesignation of 
the Crittenden County, Arkansas Portion of the Memphis, Tennessee-
Arkansas 1997 8-Hour Ozone Nonattainment Area to Attainment

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: On February 24, 2009, the State of Arkansas, through the 
Arkansas Department of Environmental Quality (ADEQ), submitted a 
request to redesignate the Arkansas portion of the bi-state Memphis, 
Tennessee-Arkansas (Memphis TN-AR) 1997 8-hour ozone nonattainment area 
to attainment for the

[[Page 2092]]

8-hour ozone National Ambient Air Quality Standard (NAAQS); and to 
approve the State Implementation Plan (SIP) revision containing a 
maintenance plan for the Arkansas portion of the bi-state Memphis TN-AR 
Area. The bi-state Memphis TN-AR 1997 8-hour ozone nonattainment area 
is composed of Memphis, Shelby County, Tennessee (Shelby County) and 
Crittenden County, Arkansas. In this action, EPA proposes to approve 
the 1997 8-hour ozone redesignation request for Crittenden County, 
Arkansas. Additionally, EPA proposes to approve the 1997 8-hour ozone 
maintenance plan for Crittenden County, including the state motor 
vehicle emissions budgets (MVEBs) for nitrogen oxides (NOX) 
and volatile organic compounds (VOCs) for the years 2006 and 2021. This 
proposed approval of Arkansas' redesignation request is based on EPA's 
determination that Arkansas has demonstrated that Crittenden County has 
met the criteria for redesignation to attainment specified in the Clean 
Air Act (CAA), including the determination that the entire Memphis TN-
AR ozone nonattainment area has attained the 1997 8-hour ozone 
standard.

DATES: Comments must be received on or before February 16, 2010.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R06-
OAR-2009-0202, by one of the following methods:
    1. https://www.regulations.gov: Follow the on-line instructions for 
submitting comments.
    2. E-mail: donaldson.guy@epa.gov.
    3. Fax: (214) 665-7263.
    4. Mail: EPA-R06-OAR-2009-0202 Air Planning Section, Multimedia 
Planning and Permitting Division, U.S. Environmental Protection Agency, 
Region 6, 1445 Ross Avenue, Suite 1200, Dallas, Texas 75202-2733.
    5. Hand Delivery or Courier: Mr. Guy Donaldson, Chief, Air Planning 
Section, Air Planning Branch, Multimedia Planning and Permitting 
Division, U.S. Environmental Protection Agency, Region 6, 1445 Ross 
Avenue, Suite 1200, Dallas, Texas 75202-2733. Such deliveries are only 
accepted during the Regional Office's normal hours of operation. The 
Regional Office's official hours of business are Monday through Friday, 
8:30 to 4:30, excluding Federal holidays.
    Instructions: Direct your comments to Docket ID No. EPA-R06-OAR-
2009-0202. EPA's policy is that all comments received will be included 
in the public docket without change and may be made available online at 
https://www.regulations.gov, including any personal information 
provided, unless the comment includes information claimed to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Do not submit through https://www.regulations.gov or e-mail, information that you consider to be CBI 
or otherwise protected. The https://www.regulations.gov Web site 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 an e-mail comment directly to EPA without 
going through https://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 
disk 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. For additional information about EPA's public 
docket visit the EPA Docket Center homepage at https://www.epa.gov/epahome/dockets.htm.
    Docket: All documents in the electronic docket are listed in the 
https://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 https://www.regulations.gov or in hard copy at the Air Planning Section, Air 
Branch, Multimedia Planning and Permitting Division, U.S. Environmental 
Protection Agency, Region 6, 1445 Ross Avenue, Suite 1200, Dallas, 
Texas 75202-2733. EPA requests that if at all possible, you contact the 
person listed in the FOR FURTHER INFORMATION CONTACT section to 
schedule your inspection. The Regional Office's official hours of 
business are Monday through Friday, 8:30 to 4:30, excluding Federal 
holidays.

FOR FURTHER INFORMATION CONTACT: Mr. Jeffrey Riley, Air Planning 
Section (6PD-L), Environmental Protection Agency, Region 6, 1445 Ross 
Avenue, Suite 700, Dallas, Texas 75202-2733, telephone (214) 665-8542; 
fax number 214-665-7263; e-mail address riley.jeffrey@epa.gov.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. What Proposed Actions Is EPA Taking?
II. What Is the Background for EPA's Proposed Actions?
III. What Are the Criteria for Redesignation?
IV. Why Is EPA Proposing These Actions?
V. What Is the Effect of EPA's Proposed Actions?
VI. What Is EPA's Analysis of the Request?
VII. What Is EPA's Analysis of Arkansas' Proposed State 
NOX and VOC MVEBs for Crittenden County, Arkansas?
VIII. What Is the Status of EPA's Adequacy Determination for the 
Proposed State NOX and VOC MVEBs for the Years 2006 and 
2021 for Crittenden County, Arkansas?
IX. Proposed Action on the Redesignation Request and Maintenance 
Plan SIP Revision Including Proposed Approval of the 2006 and 2021 
State NOX and VOC MVEBs for Crittenden County, Arkansas
X. Statutory and Executive Order Reviews

I. What Proposed Actions Is EPA Taking?

    EPA proposes several related actions, which are summarized below 
and described in greater detail throughout this notice of rulemaking:
    (1) To redesignate Crittenden County, Arkansas to attainment for 
the 1997 8-hour ozone NAAQS. EPA proposes to determine that the bi-
state Memphis, TN-AR Area has attained the 1997 8-hour ozone standard, 
and that the Crittenden County, Arkansas portion has met the 
requirements for redesignation under section 107(d)(3)(E) of the CAA. 
The bi-state Memphis, TN-AR 1997 8-hour ozone area comprises Shelby 
County in Tennessee and Crittenden County in Arkansas. Today's proposal 
addresses only the Arkansas portion of the bi-state Memphis, TN-AR 1997 
8-hour ozone area. EPA is now proposing to approve a request to change 
the legal designation of Crittenden County, Arkansas from nonattainment 
to attainment for the 1997 8-hour ozone NAAQS.
    (2) To approve Arkansas' 1997 8-hour ozone maintenance plan into 
the Arkansas SIP, including the 2006 and 2021 motor vehicle emissions 
budgets (MVEB's) that are part of the maintenance plan. EPA has already 
made a finding of adequacy for the MVEBs (74 FR 21356). These MVEBs 
apply only to Crittenden County, Arkansas. MVEB's contained in the 
Tennessee submittal for Shelby County will be addressed in a separate 
action. EPA proposes to approve Arkansas' 1997 8-hour ozone maintenance 
plan for Crittenden County (such approval being

[[Page 2093]]

one of the CAA criteria for redesignation to attainment status). The 
maintenance plan is designed to help keep the Memphis TN-AR area (of 
which Crittenden County is a part) in attainment of the 1997 8-hour 
ozone NAAQS through 2021.

II. What Is the Background for EPA's Proposed Actions?

    Ground-level ozone is not emitted directly by sources. Rather, 
emissions of NOX and VOC react in the presence of sunlight 
to form ground-level ozone. NOX and VOC are precursors of 
ozone. The CAA establishes a process for air quality management through 
the NAAQS. EPA establishes NAAQS for criteria pollutants as the maximum 
level of air pollution allowed to protect public health and welfare.
    On July 18, 1997, EPA promulgated a revised 8-hour ozone standard 
of 0.08 parts per million (ppm). This standard is more stringent than 
the previous 1-hour ozone standard. Under EPA regulations at 40 CFR 
part 50, the 8-hour ozone standard is attained when the 3-year average 
of the annual fourth highest daily maximum 8-hour average ambient air 
quality ozone concentrations is less than or equal to 0.08 ppm (i.e., 
0.084 ppm when rounding is considered). (See, 69 FR 23857 (April 30, 
2004) for further information.) Ambient air quality monitoring data for 
the 3-year period must meet a data completeness requirement. The 
ambient air quality monitoring data completeness requirement is met 
when the average percent of days with valid ambient monitoring data is 
greater than 90 percent, and no single year has less than 75 percent 
data completeness as determined in Appendix I of part 50. Specifically, 
section 2.3 of 40 CFR part 50, Appendix I, ``Comparisons with the 
Primary and Secondary Ozone Standards'' states:
    The primary and secondary ozone ambient air quality standards are 
met at an ambient air quality monitoring site when the 3-year average 
of the annual fourth-highest daily maximum 8-hour average ozone 
concentration is less than or equal to 0.08 ppm. The number of 
significant figures in the level of the standard dictates the rounding 
convention for comparing the computed 3-year average annual fourth-
highest daily maximum 8-hour average ozone concentration with the level 
of the standard. The third decimal place of the computed value is 
rounded, with values equal to or greater than 5 rounding up. Thus, a 
computed 3-year average ozone concentration of 0.085 ppm is the 
smallest value that is greater than 0.08 ppm.;
    The CAA requires EPA to designate as nonattainment any area that 
was violating the 1997 8-hour ozone NAAQS based on the three most 
recent years of ambient air quality data. The CAA contains two sets of 
provisions--subpart 1 and subpart 2--that address planning and control 
requirements for ozone nonattainment areas. (Both are found in title I, 
part D.) Subpart 1 (which EPA refers to as ``basic'' nonattainment) 
contains general, less prescriptive, requirements for nonattainment 
areas for any pollutant--including ozone--governed by a NAAQS. Subpart 
2 (which EPA refers to as ``classified'' nonattainment) provides more 
specific requirements for certain ozone nonattainment areas. Some 1997 
8-hour ozone nonattainment areas are subject only to the provisions of 
subpart 1. Other 1997 8-hour ozone nonattainment areas are also subject 
to the provisions of subpart 2. Under EPA's Phase 1 1997 8-hour ozone 
implementation rule (69 FR 23857) (Phase 1 Rule), signed on April 15, 
2004, and published April 30, 2004, an area was classified under 
subpart 2 based on its 1997 8-hour ozone design value (i.e., the 3-year 
average of the annual fourth-highest daily maximum 8-hour average ozone 
concentrations), if it had a 1-hour design value at or above 0.121 ppm 
(the lowest 1-hour design value in Table 1 of subpart 2). All other 
areas are covered under subpart 1, based upon their 8-hour ambient air 
quality design value.
    Shelby County, Tennessee was originally designated as a marginal 
nonattainment area for the 1-hour ozone standard on November 6, 1991 
(56 FR 56694). Crittenden County, Arkansas was not part of the 
nonattainment area during the 1991 1-hour designations. On February 16, 
1995 (60 FR 3352) Shelby County was redesignated as attainment for the 
1-hour ozone standard and is considered to be a 1-hour maintenance area 
subject to a CAA section 175A maintenance plan for the 1-hour standard.
    On April 30, 2004, EPA designated the Memphis, TN-AR Area (which 
then included Crittenden County, Arkansas) as a ``moderate'' 1997 8-
hour ozone nonattainment area (see, 69 FR 23857, April 30, 2004). On 
July 15, 2004, pursuant to section 181(a)(4) of the CAA, the States of 
Tennessee and Arkansas submitted a petition to EPA Regions 4 and 6, 
requesting a downward reclassification of the Memphis TN-AR 
nonattainment area from ``moderate'' to ``marginal'' for the 1997 8-
hour ozone standard. The petition was based on the area's ``moderate'' 
design value of .092 ppm being within five percent of the maximum 
``marginal'' design value of 0.091 ppm. Pursuant to Section 181(a)(4), 
areas with design values within five percent of the standard may 
request a reclassification under specific circumstances. Factors for 
EPA to consider as part of such a request are described in section 
181(a)(4) of the CAA. The petition for reclassification to ``marginal'' 
was approved by EPA, and became effective on November 22, 2004 (see, 69 
FR 56697, September 22, 2004). As a result of the downward 
classification, the new attainment date for the Memphis TN-AR 
``marginal'' nonattainment area was set at June 15, 2007, consistent 
with the CAA, with an attainment determination to be based on 2004-2006 
air quality data.
    Air quality data monitored for the Memphis TN-AR nonattainment area 
subsequently showed that the area did not attain the 1997 8-hour ozone 
NAAQS by the June 15, 2007, deadline. Section 181(b)(2)(A) of the CAA 
provides that, when EPA finds that an area failed to attain by the 
applicable date, the area is reclassified by operation of law to the 
higher of: The next higher classification or the classification 
applicable to the area's ozone design value at the time of the required 
notice under section 181(b)(2)(B). The next higher classification for 
the Memphis TN-AR Nonattainment Area was ``moderate.'' On March 28, 
2008, the Memphis TN-AR nonattainment area was reclassified as 
``moderate'' (73 FR 16547). EPA set a deadline of March 1, 2009 for the 
State to submit the moderate area SIP provisions required under the 
area's new classification (73 FR 16550).
    In 2008, the ambient ozone data for the Memphis TN-AR Area showed 
attainment of the 1997 8-hour ozone NAAQS, using data from the 3-year 
period of 2006-2008. On February 24, 2009, Arkansas requested 
redesignation of Crittenden County, Arkansas to attainment for the 1997 
8-hour ozone NAAQS. The redesignation request included three years of 
complete, quality-assured ambient air quality data for the ozone 
seasons (March 1st thru November 30th) of 2006-2008, indicating that 
the 1997 8-hour ozone NAAQS has been achieved for the entire Memphis 
TN-AR Area. Under the CAA, nonattainment areas may be redesignated to 
attainment if sufficient, complete, quality-assured data is available 
for the Administrator to determine that the area has attained the 
standard and the area meets the other CAA redesignation requirements in 
section 107(d)(3)(E).

[[Page 2094]]

III. What Are the Criteria for Redesignation?

    The CAA provides the requirements for redesignating a nonattainment 
area to attainment. Specifically, section 107(d)(3)(E) of the CAA 
allows for redesignation providing that: (1) The Administrator 
determines that the area has attained the applicable NAAQS; (2) the 
Administrator has fully approved the applicable implementation plan for 
the area under section 110(k); (3) the Administrator determines that 
the improvement in air quality is due to permanent and enforceable 
reductions in emissions resulting from implementation of the applicable 
SIP and applicable Federal air pollutant control regulations and other 
permanent and enforceable reductions; (4) the Administrator has fully 
approved a maintenance plan for the area as meeting the requirements of 
section 175A; and, (5) the state containing such area has met all 
requirements applicable to the area under section 110 and part D of the 
CAA.
    EPA provided guidance on redesignation in the General Preamble for 
the Implementation of title I of the CAA Amendments of 1990, on April 
16, 1992 (57 FR 13498), and supplemented this guidance on April 28, 
1992 (57 FR 18070). EPA has provided further guidance on processing 
redesignation requests in the following documents:
    1. ``Ozone and Carbon Monoxide Design Value Calculations,'' 
Memorandum from Bill Laxton, Director, Technical Support Division, June 
18,1990;
    2. ``Maintenance Plans for Redesignation of Ozone and Carbon 
Monoxide Nonattainment Areas,'' Memorandum from G.T. Helms, Chief, 
Ozone/Carbon Monoxide Programs Branch, April 30, 1992;
    3. ``Contingency Measures for Ozone and Carbon Monoxide (CO) 
Redesignations,'' Memorandum from G.T. Helms, Chief, Ozone/Carbon 
Monoxide Programs Branch, June 1, 1992;
    4. ``Procedures for Processing Requests to Redesignate Areas to 
Attainment,'' Memorandum from John Calcagni, Director, Air Quality 
Management Division, September 4, 1992 (hereafter referred to as the 
``Calcagni Memorandum'');
    5. ``State Implementation Plan (SIP) Actions Submitted in Response 
to Clean Air Act (ACT) Deadlines,'' Memorandum from John Calcagni, 
Director, Air Quality Management Division, October 28, 1992;
    6. ``Technical Support Documents (TSD's) for Redesignation of Ozone 
and Carbon Monoxide (CO) Nonattainment Areas,'' Memorandum from G. T. 
Helms, Chief, Ozone/Carbon Monoxide Programs Branch, August 17, 1993;
    7. ``State Implementation Plan (SIP) Requirements for Areas 
Submitting Requests for Redesignation to Attainment of the Ozone and 
Carbon Monoxide (CO) National Ambient Air Quality Standards (NAAQS) On 
or After November 15, 1992,'' Memorandum from Michael H. Shapiro, 
Acting Assistant Administrator for Air and Radiation, September 17, 
1993;
    8. ``Use of Actual Emissions in Maintenance Demonstrations for 
Ozone and CO Nonattainment Areas,'' Memorandum from D. Kent Berry, 
Acting Director, Air Quality Management Division, November 30, 1993;
    9. ``Part D New Source Review (Part D NSR) Requirements for Areas 
Requesting Redesignation to Attainment,'' Memorandum from Mary D. 
Nichols, Assistant Administrator for Air and Radiation, October 14, 
1994; and
    10. ``Reasonable Further Progress, Attainment Demonstration, and 
Related Requirements for Ozone Nonattainment Areas Meeting the Ozone 
National Ambient Air Quality Standard,'' Memorandum from John S. Seitz, 
Director, Office of Air Quality Planning and Standards, May 10, 1995.

IV. Why Is EPA Proposing These Actions?

    On February 24, 2009, Arkansas requested redesignation of the 
Arkansas portion (Crittenden County) of the bi-state Memphis TN-AR 1997 
8-hour ozone nonattainment area to attainment for the 1997 8-hour ozone 
standard. EPA's evaluation indicates that the bi-state Memphis Area has 
attained the standard and that Crittenden County has met the 
requirements for redesignation set forth in section 107(d)(3)(E), 
including the maintenance plan requirements under section 175A of the 
CAA. EPA is also announcing the status of its adequacy determination 
and proposing approval of the 2006 and 2021 NOX and VOC 
MVEBs which are relevant to the requested redesignation.

V. What Is the Effect of EPA's Proposed Actions?

    Approval of Arkansas' redesignation request would change the legal 
designation of Crittenden County for the 1997 8-hour ozone NAAQS found 
at 40 CFR part 81. Approval of Arkansas' request would also incorporate 
into the Arkansas SIP, a plan for Crittenden County for maintaining the 
1997 8-hour ozone NAAQS in the area through 2021. This maintenance plan 
includes contingency measures to remedy future violations of the 1997 
8-hour ozone NAAQS. The maintenance plan also establishes state 
NOX and VOC MVEBs for Crittenden County. Table 1 identifies 
the state NOX and VOC MVEBs for the year 2006 and 2021 for 
Crittenden County.

              Table 1--Crittenden County NOX and VOC MVEBs
                      [Summer season tons per day]
------------------------------------------------------------------------
                                                          2006     2021
------------------------------------------------------------------------
NOX...................................................     6.27     1.84
VOC...................................................     2.95     1.39
------------------------------------------------------------------------

    Approval of Arkansas' maintenance plan would also result in 
approval of the NOX and VOC state MVEBs. Additionally, EPA 
is notifying the public of the status of its adequacy determination for 
the 2006 and 2021 NOX and VOC state MVEBs pursuant to 40 CFR 
93.118(f)(1).

VI. What Is EPA's Analysis of the Request?

    EPA proposes to determine that the Crittenden County portion of the 
Memphis TN-AR 1997 8-hour ozone nonattainment area has attained the 
1997 8-hour ozone standard, and that all other redesignation criteria 
have been met for that portion of the Memphis TN-AR area. The basis for 
EPA's determination for the area is discussed in greater detail below.
    Criteria (1)--Crittenden County, Arkansas has attained the 1997 8-
hour ozone NAAQS.
    EPA proposes to determine that the Crittenden County portion of the 
Memphis TN-AR area has attained the 1997 8-hour ozone NAAQS. For ozone, 
an area may be considered to be attaining the 1997 8-hour ozone NAAQS 
if the air quality in the nonattainment area meets the standard, as 
determined in accordance with 40 CFR 50.10 and Appendix I of part 50, 
based on three complete, consecutive calendar years of quality-assured 
air quality monitoring data. To attain this standard, the 3-year 
average of the fourth-highest daily maximum 1997 8-hour average ozone 
concentrations measured at each monitor within an area over each year 
must not exceed 0.08 ppm. Based on the rounding convention described in 
40 CFR part 50, Appendix I, the standard is attained if the design 
value is 0.084 ppm or below. The data must be collected and quality-
assured in accordance with 40 CFR part 58, and recorded in the EPA Air 
Quality System (AQS). The monitors generally should

[[Page 2095]]

have remained at the same location for the duration of the monitoring 
period required for demonstrating attainment.
    EPA reviewed ozone monitoring data from ambient ozone monitoring 
stations in the Memphis TN-AR area for the ozone season from 2006-2008. 
This data has been quality assured and is recorded in AQS. The fourth 
high averages for 2006, 2007 and 2008, and the 3-year average of these 
values (i.e., design values), are summarized in Table 2:

  Table 2--Annual 4th Max High and Design Value Concentration for 1997 8-Hour Ozone for the Memphis, TN-AR Area
                                             [In parts per million]
----------------------------------------------------------------------------------------------------------------
                 County                              Shelby County,  Tennessee              Crittenden County,
-----------------------------------------------------------------------------------------        Arkansas
                                              Memphis-Frayser                            -----------------------
            Monitor (AQS ID)              Boulevard (47-   Edmond Orgill Park     Marion (05-
                                                 157-0021)        (47-157-1004)         035-0005)
----------------------------------------------------------------------------------------------------------------
2006....................................                 0.083                   0.084                   0.089
2007....................................                 0.081                   0.080                   0.084
2008....................................                 0.084                   0.077                   0.074
Design Value............................                 0.082                   0.080                   0.082
----------------------------------------------------------------------------------------------------------------

    As discussed above, the design value for an area is the highest 
design value recorded at any monitor in the area. Therefore, the design 
value for the Memphis TN-AR Area is 0.082 ppm, which meets the standard 
as described above. Preliminary data from 2009 also indicate the area 
continues to attain the standard. The data from 2009 is considered 
preliminary because it has not yet completed full data certification. 
As discussed in more detail below, Arkansas has committed to continue 
monitoring in this area in accordance with 40 CFR part 58. The data 
submitted by Arkansas provides an adequate demonstration that 
Crittenden County (as part of the Memphis TN-AR area) has attained the 
1997 8-hour ozone NAAQS.
    Criteria (2)--Arkansas has a fully approved SIP under section 
110(k) for Crittenden County and Criteria (5)--Arkansas has met all 
Applicable Requirements under Section 110 and part D of the CAA.
    Below is a summary of how these two criteria were met.
    EPA has determined that Arkansas has met all applicable SIP 
requirements for Crittenden County under section 110 of the CAA 
(general SIP requirements). EPA has also determined that the Arkansas 
SIP satisfies the criterion that it meet applicable SIP requirements 
under part D of title I of the CAA (including requirements specific to 
subpart 2 marginal 1997 8-hour ozone nonattainment areas) in accordance 
with section 107(d)(3)(E)(v). In addition, EPA has determined that the 
SIP is fully approved with respect to all requirements applicable for 
purposes of redesignation in accordance with section 107(d)(3)(E)(ii). 
In making these determinations, EPA ascertained which requirements are 
applicable to the area and that if applicable, they are fully approved 
under section 110(k). SIPs must be fully approved only with respect to 
applicable requirements.
a. Crittenden County, Arkansas Has Met All Applicable Requirements 
Under Section 110 and Part D of the CAA
    The September 4, 1992, Calcagni Memorandum (see ``Procedures for 
Processing Requests to Redesignate Areas to Attainment,'' Memorandum 
from John Calcagni, Director, Air Quality Management Division, 
September 4, 1992) describes EPA's interpretation of section 
107(d)(3)(E). Under this interpretation, to qualify for redesignation, 
states requesting redesignation to attainment must meet only the 
relevant CAA requirements that come due prior to the submittal of a 
complete redesignation request. See also, Michael Shapiro Memorandum, 
(``SIP Requirements for Areas Submitting Requests for Redesignation to 
Attainment of the Ozone and Carbon Monoxide NAAQS On or After November 
15, 1992,'' September 17, 1993), and 60 FR 12459, 12465-66 (March 7, 
1995) (redesignation of Detroit-Ann Arbor, Michigan). Applicable 
requirements of the CAA that come due subsequent to the area's 
submittal of a complete redesignation request remain applicable until a 
redesignation is approved, but are not required as a prerequisite to 
redesignation. See, section 175A(c) of the CAA; Sierra Club, 375 F.3d 
537 (7th Cir. 2004); see also, 68 FR 25424, 25427 (May 12, 2003) 
(redesignation of St. Louis, Missouri).
    General SIP requirements. Section 110(a)(2) of title I of the CAA 
delineates the general requirements for a SIP, which include 
enforceable emissions limitations and other control measures, means, or 
techniques, provisions for the establishment and operation of 
appropriate devices necessary to collect data on ambient air quality, 
and programs to enforce the limitations. General SIP elements and 
requirements are delineated in section 110(a)(2) of title I, part A of 
the CAA. These requirements include, but are not limited to, the 
following: Submittal of a SIP that has been adopted by the state after 
reasonable public notice and hearing; provisions for establishment and 
operation of appropriate procedures needed to monitor ambient air 
quality; implementation of a source permit program; provisions for the 
implementation of part C requirements (Prevention of Significant 
Deterioration (PSD)) and provisions for the implementation of part D 
requirements (NSR permit programs); provisions for air pollution 
modeling; and provisions for public and local agency participation in 
planning and emission control rule development.
    Section 110(a)(2)(D) requires that SIPs contain certain measures to 
prevent sources in a state from significantly contributing to air 
quality problems in another state. To implement this provision, EPA has 
required certain states to establish programs to address the transport 
of air pollutants (NOX SIP Call, Clean Air Interstate Rule 
(CAIR)). The section 110(a)(2)(D) requirements for a state are not 
linked with a particular nonattainment area's designation and 
classification in that state. EPA believes that the requirements linked 
with a particular nonattainment area's designation and classifications 
are the relevant measures to evaluate in reviewing a redesignation 
request. The transport SIP submittal requirements, where applicable, 
continue to apply to a state regardless of

[[Page 2096]]

the designation of any one particular area in the state. Thus, we do 
not believe that the CAA's interstate transport requirements should be 
construed to be applicable requirements for purposes of redesignation.
    In addition, EPA believes that the other section 110 elements not 
connected with nonattainment plan submissions and not linked with an 
area's attainment status are not applicable requirements for purposes 
of redesignation. The area will still be subject to these requirements 
after the area is redesignated. The section 110 and part D requirements 
that are linked with a particular area's designation and classification 
are the relevant measures to evaluate in reviewing a redesignation 
request. This approach is consistent with EPA's existing policy on 
applicability (i.e., for redesignations) of conformity and oxygenated 
fuels requirements, as well as with section 184 ozone transport 
requirements. See, Reading, Pennsylvania, proposed and final 
rulemakings (61 FR 53174-53176, October 10, 1996), (62 FR 24826, May 7, 
1997); Cleveland-Akron-Loraine, Ohio, final rulemaking (61 FR 20458, 
May 7, 1996); and Tampa, Florida, final rulemaking at (60 FR 62748, 
December 7, 1995). See also, the discussion on this issue in the 
Cincinnati, Ohio redesignation (65 FR 37890, June 19, 2000), and in the 
Pittsburgh, Pennsylvania redesignation (66 FR 50399, October 19, 2001).
    EPA believes that section 110 elements not linked to the area's 
nonattainment status are not applicable for purposes of redesignation. 
Therefore, as discussed above, for purposes of redesignation, they are 
not considered applicable requirements. We have reviewed the Arkansas 
SIP and have concluded it meets the general requirements of section 
110, to the extent that these are applicable for redesignation. EPA has 
previously approved provisions in the Arkansas SIP addressing section 
110 elements under the 1-hour ozone NAAQS (See, 40 CFR 52.172).
    In a letter to EPA dated March 28, 2008, the State set forth its 
belief that the existing SIP is also sufficient to meet the CAA 
110(a)(2) requirements for the 1997 8-hour ozone NAAQS. EPA has not yet 
approved this submission, but such approval is not necessary for 
purposes of redesignation.
    Part D requirements. EPA has also determined that the Arkansas SIP 
meets applicable SIP requirements under part D of the CAA. Sections 
172-176 of the CAA, found in subpart 1 of part D, set forth the basic 
nonattainment requirements applicable to all nonattainment areas. 
Section 182 of the CAA, found in subpart 2 of part D, establishes 
additional specific requirements depending on the area's nonattainment 
classification and applies to the Memphis TN-AR area. As discussed in 
Section II, Crittenden County was classified as marginal, and then 
reclassified to moderate. In the reclassification, EPA required that 
the necessary SIP revisions for the new moderate area requirements be 
submitted by both Tennessee and Arkansas as expeditiously as 
practicable, but no later than March 1, 2009. The request for 
redesignation was submitted by Arkansas on February 24, 2009, prior to 
the date that the moderate area requirements came due. Thus, for 
purposes of redesignation, only the marginal area requirements under 
Part D, subpart 2 are applicable to Crittenden County.
    A SIP revision submitted to EPA by the State of Arkansas on 
November 19, 2007 satisfied the marginal area requirements set forth in 
section 182(a)(1). This submittal consisted of an emissions inventory 
for the year 2002 containing NOX, VOC and carbon monoxide 
(CO) emissions as precursors to ozone formation, as well as a revision 
to State Regulation 19, Chapter 7 (Sampling, Monitoring, and Reporting 
Requirements), to require emissions statements. EPA approved this SIP 
revision on January 15, 2009 (74 FR 2383). Requirements set forth in 
sections 182(a)(2)(A) (Reasonably Available Control Technology 
Corrections) and 182(a)(2)(B) (Savings Clause for Vehicle Inspection 
and Maintenance) are not applicable to Crittenden County due to its 
status of attainment of the 1-hour ozone standard. Requirements set 
forth in section 182(a)(2)(C) (Permit Programs) are discussed in the 
NSR Requirements section of this notice.
    In addition to the fact that only the marginal classification part 
D requirements became due prior to submission of the redesignation 
request and therefore are applicable for purposes of redesignation, EPA 
believes it is reasonable to interpret the conformity requirements as 
not requiring approval prior to redesignation.
    Section 176 Conformity Requirements. Section 176(c) of the CAA 
requires states to establish criteria and procedures to ensure that 
federally supported or funded projects conform to the air quality 
planning goals in the applicable SIP. The requirement to determine 
conformity applies to transportation plans, programs and projects 
developed, funded or approved under title 23 of the United States Code 
(U.S.C.) and the Federal Transit Act (transportation conformity) as 
well as to all other federally supported or funded projects (general 
conformity). State conformity revisions must be consistent with Federal 
conformity regulations relating to consultation, enforcement and 
enforceability that the CAA required the EPA to promulgate.
    EPA believes it is reasonable to interpret the conformity SIP 
requirements as not applying for purposes of evaluating the 
redesignation request under section 107(d) because state conformity 
rules are still required after redesignation and Federal conformity 
rules apply where state rules have not been approved. See, Wall v. EPA, 
265 F.3d 426, 438-40 (6th Cir. 2001) (upholding this interpretation). 
See also, 60 FR 62748 (December 7, 1995, Tampa, Florida). Although 
Crittenden County does not currently have fully approved conformity 
rules, a Memorandum of Agreement outlining interagency consultation 
procedures is in place for transportation conformity purposes.
    NSR Requirements. Arkansas' permitting requirements for major 
sources in or impacting upon nonattainment areas are set forth in 
``Regulation No. 31--Nonattainment New Source Review Requirements.'' On 
July 3, 2006, Arkansas submitted Regulation No. 31 to address the 
marginal Nonattainment New Source Review (NNSR) permitting requirements 
in Crittenden County, and EPA approved the submittal on April 12, 2007 
(72 FR 18394). This regulation applies to the construction and 
modification of any major stationary source of air pollution in a 
nonattainment area, as required by part D of Title I of the Act. 
Regulation No. 31 also includes provisions that implement EPA's 
designation of Crittenden County as an Economic Development Zone (EDZ) 
subject to the requirements of Section 173(a)(1)(B) of the Act. These 
provisions establish VOC and NOX emissions caps and provide 
for the Director of ADEQ to grant growth allowances to affected sources 
in lieu of meeting the NNSR offset requirement. Arkansas has maintained 
that sources locating to the Memphis area will continue to undergo new 
source review requirements and existing source control will continue 
under the NNSR/EDZ program until Crittenden County is redesignated to 
attainment.
    Upon redesignation, however, the identification of Crittenden 
County as a section 173 EDZ expires under federal law. The rules that 
apply for the 1997 8-hour ozone standard after

[[Page 2097]]

redesignation would be those contained in the Prevention of Significant 
Deterioration (PSD) SIP program. The State must reapply for EDZ status 
should Crittenden County be designated nonattainment under a revised 8-
hour primary ozone standard. In any event, EPA notes that fully 
approved NSR is not required for redesignation to attainment as long as 
PSD applies after redesignation, and the area has shown it can attain 
and maintain without nonattainment NSR.
    EPA has also determined that areas being redesignated need not 
comply with the requirement that a nonattainment NSR program be 
approved prior to redesignation, provided that the area demonstrates 
maintenance of the standard without a part D NSR program in effect 
since PSD requirements will apply after redesignation. The rationale 
for this view is described in a memorandum from Mary Nichols, Assistant 
Administrator for Air and Radiation, dated October 14, 1994, entitled 
``Part D New Source Review (Part D NSR) Requirements for Areas 
Requesting Redesignation to Attainment.''
    Arkansas in its submittal for Crittenden County showed that sources 
locating to the Crittenden area will be subject to PSD requirements and 
has demonstrated that Crittenden County will be able to maintain the 
standard without a part D nonattainment NSR program in effect. 
Therefore, Arkansas need not have a fully approved part D NSR program 
prior to approval of the redesignation request. Arkansas's PSD program 
will become effective in Crittenden County upon redesignation to 
attainment. See, rulemakings for Detroit, Michigan (60 FR 12467-12468, 
March 7, 1995); Cleveland-Akron-Lorraine, Ohio (61 FR 20458, 20469-70, 
May 7, 1996); Louisville, Kentucky (66 FR 53665, October 23, 2001); 
Grand Rapids, Michigan (61 FR 31834-31837, June 21, 1996). Thus, EPA 
believes that Crittenden County, Arkansas has satisfied all applicable 
requirements for purposes of redesignation under section 110 and part D 
of the CAA.
b. Crittenden County, Arkansas Has a Fully Approved Applicable SIP 
Under Section 110(k) of the CAA
    EPA has fully approved the applicable Arkansas SIP for Crittenden 
County, under section 110(k) of the CAA for all requirements applicable 
for purposes of redesignation. EPA may rely on prior SIP approvals in 
approving a redesignation request (see Calcagni Memorandum at p. 3; 
Southwestern Pennsylvania Growth Alliance v. Browner, 144 F.3d 984, 
989-90 (6th Cir. 1998); Wall, 265 F.3d 426, at 438) plus any additional 
measures it may approve in conjunction with a redesignation action. 
See, 68 FR 25426 (May 12, 2003) and citations therein.
    As indicated above, EPA believes that the section 110 elements not 
connected with nonattainment plan submissions and not linked to the 
area's nonattainment status are not applicable requirements for 
purposes of redesignation. EPA also believes that since the moderate 
area part D requirements applicable for purposes of redesignation did 
not become due prior to submission of the redesignation request, they 
also are not applicable requirements for purposes of redesignation. As 
set forth above, the area has met all other applicable requirements for 
purposes of redesignation under its prior marginal classification.
    Criteria (3)--The air quality improvement in the Memphis TN-AR 1997 
8-hour Ozone Area is due to permanent and enforceable reductions in 
emissions resulting from implementation of the SIP and applicable 
federal air pollution control regulations and other permanent and 
enforceable reductions.
    EPA believes that Arkansas has demonstrated that the observed air 
quality improvement in the Memphis-Crittenden County Nonattainment Area 
is due to permanent and enforceable reductions in emissions resulting 
from implementation of the SIP, Federal measures, and other state 
adopted measures. Additionally, new emissions control programs for 
fuels and motor vehicles will help ensure a continued decrease in 
emissions throughout the region.
    Because Crittenden County is itself largely rural in nature, 
measured reductions in ozone concentrations in and around Crittenden 
County are largely attributable to permanent and enforceable reductions 
from emission sources of VOCs and NOX in the Memphis area. 
There were reductions in Crittenden County. Table 3 summarizes several 
of the measures adopted that resulted in emissions reductions in 
Crittenden County.

         Table 3--Crittenden County Emission Reductions Programs
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
                             Mobile Sources
------------------------------------------------------------------------
[cir] Tier 2 Fuel and Vehicle Emission Standards.
[cir] Federal Motor Vehicle Control Program.
[cir] Heavy Duty Diesel Rule (2007 Highway Rule).
------------------------------------------------------------------------
                        State and Local Measures
------------------------------------------------------------------------
[cir] Stage I Vapor Recovery.
[cir] Proform Company, LLC closure, air permit voided.
[cir] CIBA Corporation reclassified to minor source, MACT standard
 modifications.
------------------------------------------------------------------------
                     Additional Voluntary Reductions
------------------------------------------------------------------------
[cir] Diesel Emissions Reduction Act--ADEQ received State Clean Diesel
 Grant in October 2008.
[cir] Retrofit of city and county (21 on-road, 12 non-road trucks) w/
 diesel oxidation catalyst.
[cir] Retrofit of 50 school buses w/diesel oxidation catalyst.
[cir] Retrofit of 12 refuse trucks w/diesel oxidation catalyst.
[cir] 196 California Air Resources Board certified gas cans exchanged in
 Crittenden County.
[cir] Truck stop electrification (equipped 65 parking spaces in
 Crittenden County).
------------------------------------------------------------------------

    Emission reductions in Shelby County as a result of federal motor 
vehicle controls from 2002 to 2006 are estimated to be 7 tons per day 
of VOCs and 28 tons per day of NOX. Additionally, continuing 
new emissions control programs will help to ensure a further decrease 
in emissions throughout the area in the future. Crittenden County is 
expected to receive upwind benefits in emission reductions.
    Regarding point source emissions, the Tennessee Valley Authority's 
(TVA) Allen Steam Plant located in Shelby County operates three coal-
fired boilers. As a result of EPA's ``Finding of Significant 
Contribution and Rulemaking for Certain States in the Ozone Transport 
Assessment Group Region for Purposes of Reducing Region Transport of 
Ozone'' (NOX SIP Call), TVA began operation of two selective 
catalytic reduction (SCR) control units during the 2002 ozone control 
season, May 1st through September 30th. The third SCR began operating 
in 2003. Ozone season daily NOX reductions in the area as a 
result of these controls equal approximately 45 tons per day.
    These are substantial reductions when compared to the remaining 
total NOX inventory from all sources in Shelby and 
Crittenden Counties in 2006 of 116.81 tons per day (99.09 tons per day 
in Shelby County and 17.72 tons per day in Crittenden County) and a VOC 
inventory of 128.67 tons per day (99.11 tons per day in Shelby County 
and 29.56 tons per day in Crittenden County).

[[Page 2098]]

    Because of the uncertainty introduced by the recent court actions 
affecting the CAIR Rule and NOX SIP Call, EPA undertook an 
analysis of the changes in NOX expected across a broader 
region. In particular, EPA reviewed available projections of 
NOX emissions from nearby states from 2002 to 2018. These 
values are presented in Tables 4 and 5:

                          Table 4--2002 Base Annual Emission Inventory Summary for NOX*
----------------------------------------------------------------------------------------------------------------
                                             Non-EGU
             States              EGU point    point     Non-road     area       Mobile      Fires       Total
----------------------------------------------------------------------------------------------------------------
AR.............................     24,722     47,698     62,472     21,700      141,894      5,492      303,978
KY.............................    201,928     38,434    104,571     39,507      156,417        534      541,391
LA.............................    111,703    199,218    114,711     93,069      180,664      6,942      706,307
MS.............................     40,433     61,533     88,787      4,200      111,914        308      307,175
MO.............................    145,438     36,144     99,306     32,435      189,852      2,442      505,617
TN.............................    152,137     64,344     96,827     17,844      238,577        217      569,946
                                --------------------------------------------------------------------------------
    Total......................    676,361    447,371    566,674    208,755    1,019,318     15,935    2,934,414
----------------------------------------------------------------------------------------------------------------
* From Tennessee Regional Haze SIP, Appendix D, page D.3-5 and support table for Technical Support Document for
  CENRAP Emissions and Air Quality Modeling to Support Regional Haze State Implementation Plans, page 2-40,
  figure 2-4.


                          Table 5--2018 Base Annual Emission Inventory Summary for NOX*
----------------------------------------------------------------------------------------------------------------
                                               Non-EGU
              States               EGU point    point     Non-road     Area      Mobile     Fires       Total
----------------------------------------------------------------------------------------------------------------
AR...............................     34,938     36,169     34,305     25,672     33,640      5,600      170,324
KY...............................     64,378     41,034     79,392     44,346     52,263        714      282,127
LA...............................     44,485    225,748    106,685    114,374     44,806      6,969      543,067
MS...............................     21,535     61,252     68,252      4,483     30,619      1,073      187,214
MO...............................     83,181     51,489     59,625     35,213     50,861      2,442      282,811
TN...............................     31,715     62,519     70,226     19,597     69,385        405      253,847
                                  ------------------------------------------------------------------------------
    Total........................    280,232    478,211    418,485    243,685    281,574     17,203    1,708,390
----------------------------------------------------------------------------------------------------------------
* From Tennessee Regional Haze SIP, Appendix D, page D.3-5 and support table for Technical Support Document for
  CENRAP Emissions and Air Quality Modeling to Support Regional Haze State Implementation Plans, page 2-40,
  figure 2-4.

    From 2002 to 2018 NOX emissions are projected to 
decrease in the region by 1,215,024 tons/year or 41.4 percent in all. 
EGU NOX anticipated decreases due to CAIR and the 
NOX SIP Call were projected to be 198,150 tons per year. 
However, the largest source in this region remains the motor vehicle 
sector, which is projected to decrease 737,744 tons per year. Hence 
even without EGU controls on NOX emissions, total 
NOX emissions are projected to continually decrease 
throughout the maintenance period. As is noted in the following 
paragraph, the NOX SIP Call will remain in effect.
    The NOX SIP Call requires states to make significant, 
specific emissions reductions. It also provided a mechanism, the 
NOX Budget Trading Program, which states could use to 
achieve those reductions. When EPA promulgated CAIR, it discontinued 
(starting in 2009) the NOX Budget Trading Program, 40 CFR 
51.121(r), but created another mechanism--the CAIR ozone season trading 
program--which states could use to meet their SIP Call obligations, 70 
FR 25289-90. EPA notes that a number of states, when submitting SIP 
revisions to require sources to participate in the CAIR ozone season 
trading program, removed the SIP provisions that required sources to 
participate in the NOX Budget Trading Program. In addition, 
because the provisions of CAIR including the ozone season 
NOX trading program remain in place during the remand (North 
Carolina v. EPA, 550 F.3d 1176 (DC Cir. Dec. 23, 2008)), EPA is not 
currently administering the NOX Budget Trading Program. 
Nonetheless, all states regardless of the current status of their 
regulations that previously required participation in the 
NOX Budget Trading Program, will remain subject to all of 
the requirements in the NOX SIP Call even if the existing 
CAIR ozone season trading program is withdrawn or altered. In addition, 
the anti-backsliding provisions of 40 CFR 51.905(f) specifically 
provide that the provisions of the NOX SIP Call, including 
the statewide NOX emission budgets, continue to apply after 
revocation of the 1-hr standard.
    All NOX SIP Call states have SIPs that currently satisfy 
their obligations under the SIP Call, the SIP Call reduction 
requirements are being met, and EPA will continue to enforce the 
requirements of the NOX SIP Call even after any response to 
the CAIR remand. For these reasons, EPA believes that regardless of the 
status of the CAIR program, the NOX SIP Call requirements 
can be relied upon in demonstrating maintenance. Thus, the 
NOX SIP Call adds to assurances that the area will remain in 
attainment.
    These regional projections of emissions data have been prepared 
only through 2018. However, since motor vehicle and off road emissions 
continue to decrease long after a rule is adopted as the engine 
population is gradually replaced by newer engines, it is reasonable to 
assume that this projected decrease in regional NOX 
emissions from mobile and non-road sources should continue through 2020 
and assure that ozone in the Memphis region will continue to decline 
throughout the 10 year maintenance period. Hence we believe the 
projected regional NOX reductions are adequate to assure 
that the Memphis region will continue demonstrating maintenance 
throughout the 10 year maintenance period.
    Criteria (4)--The area has a fully approved maintenance plan 
pursuant to section 175A of the CAA.
    In conjunction with its request to redesignate Crittenden County, 
Arkansas (as part of the Memphis TN-AR 1997 8-hour ozone nonattainment 
area) to attainment, Arkansas submitted a SIP revision to provide for 
the maintenance of the 1997 8-hour ozone NAAQS for at least 10 years 
after the

[[Page 2099]]

effective date of redesignation to attainment.
a. What is required in a maintenance plan?
    Section 175A of the CAA sets forth the elements of a maintenance 
plan for areas seeking redesignation from nonattainment to attainment. 
Under section 175A, the plan must demonstrate continued attainment of 
the applicable NAAQS for at least 10 years after the Administrator 
approves a redesignation to attainment. Eight years after the 
redesignation, the State of Arkansas must submit a revised maintenance 
plan, which demonstrates that attainment will continue to be maintained 
for the 10 years following the initial 10-year period. To address the 
possibility of future NAAQS violations, the maintenance plan must 
contain such contingency measures, with a schedule for implementation 
as EPA deems necessary to assure prompt correction of any future 8-hour 
ozone violations. Section 175A of the CAA sets forth the elements of a 
maintenance plan for areas seeking redesignation from nonattainment to 
attainment. The Calcagni Memorandum provides additional guidance on the 
content of a maintenance plan. The Calcagni Memorandum explains that an 
ozone maintenance plan should address five requirements: The attainment 
emissions inventory, maintenance demonstration, monitoring, 
verification of continued attainment, and a contingency plan. As is 
discussed more fully below, Arkansas' maintenance plan includes all the 
necessary components and is approvable as part of the redesignation 
request.
b. Attainment Emissions Inventory
    In coordination with Shelby County, Tennessee, Arkansas selected 
2006 ``the attainment year'' for the purposes of demonstrating 
attainment of the 1997 8[dash]hour ozone NAAQS. This attainment 
inventory identifies the level of emissions in the area, which is 
sufficient to attain the 1997 8-hour ozone standard. Arkansas began 
development of this attainment inventory by first developing a baseline 
emissions inventory for the Memphis area. The year 2006 was chosen as 
the base year for developing a comprehensive ozone precursor emissions 
inventory for which projected emissions could be developed for 2009, 
2012, 2015, 2017, 2018 and 2021. The projected inventory estimates 
emissions forward to 2021, which is beyond the 10-year interval 
required in Section 175(A) of the CAA. Non-road mobile emissions 
estimates were based on the EPA's NONROAD2005 model. On-road mobile 
source emissions were calculated using EPA's MOBILE6.2 emission factors 
model. The 2006 VOC and NOX emissions, as well as the 
emissions for other years, for Crittenden County were developed 
consistent with EPA guidance, and are summarized in Tables 6 and 7 in 
the following subsection.
c. Maintenance Demonstration
    The February 24, 2009 final submittal includes a maintenance plan 
for Crittenden County. This demonstration:
    (i) Shows compliance and maintenance of the 1997 8-hour ozone 
standard by providing information to support the demonstration that 
current and future emissions of VOC and NOX remain at or 
below attainment year 2006 emissions levels. The year 2006 was chosen 
as the attainment year because it is one of the most recent three years 
(i.e., 2006, 2007, and 2008) for which Crittenden County has clean air 
quality data for the 1997 8-hour ozone standard.
    (ii) Uses 2006 as the attainment year and includes future emission 
inventory projections for 2009, 2012, 2015, 2017, 2018, and 2021.
    (iii) Identifies an ``out year,'' at least 10 years (and beyond) 
after the time necessary for EPA to review and approve the maintenance 
plan. Per 40 CFR part 93, state NOX and VOC MVEBs were 
established for the last year (2021) of the maintenance plan. 
Additionally, Arkansas chose, through interagency consultation, to 
establish MVEBs for the year 2006 for NOX and VOC. EPA has 
already notified the public of its adequacy determination for these 
2006 and 2021 MVEBs pursuant to 40 CFR 93.118(f)(1) (74 FR 21356).
    (iv) Provides the following actual and projected emissions 
inventories, in tons per day (tpd) for Crittenden County, Arkansas. 
See, Tables 6 and 7.

                                    Table 6--Crittenden County VOC Emissions
                                          [Summer season tons per day]
----------------------------------------------------------------------------------------------------------------
                 Source category                     2006     2009     2012     2015     2017     2018     2021
----------------------------------------------------------------------------------------------------------------
Point............................................     2.13     2.17     2.27     2.36     2.43     2.47     2.62
Area.............................................    21.32    21.30    21.49    21.68    21.80    21.89    22.14
On-road *........................................     3.12     2.63     2.30     1.97     1.75     1.68     1.50
Non-road **......................................     2.99     2.85     2.60     2.36     2.19     2.14     1.97
                                                  --------------------------------------------------------------
    Total........................................    29.56    28.94    28.65    28.36    28.17    28.18    28.23
----------------------------------------------------------------------------------------------------------------
* Calculated using MOBILE 6.2.
** Calculated using NONROAD2005c.


                                  Table 7--Crittenden County Area NOX Emissions
                                          [Summer season tons per day]
----------------------------------------------------------------------------------------------------------------
                 Source category                     2006     2009     2012     2015     2017     2018     2021
----------------------------------------------------------------------------------------------------------------
Point............................................     1.09     1.15     1.22     1.29     1.34     1.37     1.45
Area.............................................     0.90     0.90     0.91     0.91     0.92     0.92     0.93
On-road *........................................     6.27     5.13     4.12     3.12     2.45     2.30     1.84
Non-road **......................................     9.46     9.38     9.10     8.82     8.63     8.39     7.66
                                                  --------------------------------------------------------------
    Total........................................    17.72    16.56    15.35    14.14    13.34    12.97    11.88
----------------------------------------------------------------------------------------------------------------
* Calculated using MOBILE 6.2.
** Calculated using NONROAD2005c.


[[Page 2100]]

    Although the Arkansas SIP submission provided NOX and 
VOC emissions for the attainment and future years for Crittenden 
County, EPA has considered emissions for the entire Memphis TN-AR area 
for demonstration of maintenance. Maintenance is demonstrated if the 
future year NOX and VOC emission for the entire area remains 
at or below the level of the attainment year emissions. Both Tennessee 
and Arkansas chose 2006 for their ``attainment year'' for this area. It 
is important to note that this area is composed of two counties (Shelby 
County, Tennessee and Crittenden County, Arkansas) for which emissions 
should be considered. The area and point sources for both counties 
indicate a steady NOX and VOC emission increase. However, 
large projected reductions in mobile source emissions more than 
compensate for this relatively small increase. Moreover, EPA's review 
of the entire area's total inventory for NOX and VOCs 
indicate that future total area emissions are below the level of the 
total area attainment year emissions. Therefore, EPA believes that the 
1997 8[dash]hour ozone standard will be maintained in the future for 
the Memphis TN-AR area.
d. Monitoring Network
    There are currently three monitors measuring ozone in the Memphis 
TN-AR Area (two in Shelby County, Tennessee and one in Crittenden 
County, Arkansas). ADEQ has committed, in the maintenance plan, to 
continue operation of the monitor in Crittenden County in compliance 
with 40 CFR part 58, and has addressed the requirement for monitoring.
e. Verification of Continued Attainment
    Arkansas has the legal authority to enforce and implement the 
requirements of the ozone maintenance plan. This includes the authority 
to adopt, implement and enforce any subsequent emissions control 
contingency measures determined to be necessary to correct future ozone 
attainment problems.
    Arkansas will track the progress of the maintenance plan by 
performing future reviews of triennial emissions inventory for 
Crittenden County using the latest emissions factors, models and 
methodologies. For these periodic inventories, Crittenden County will 
review the assumptions made for the purpose of the maintenance 
demonstration concerning projected growth of activity levels. If any of 
these assumptions appear to have changed substantially, Arkansas will 
re-project emissions.
f. Contingency Plan
    The contingency plan provisions are designed to promptly correct a 
violation of the NAAQS that occurs after redesignation. Section 175A of 
the CAA requires that a maintenance plan include such contingency 
measures as EPA deems necessary to assure that the state will promptly 
correct a violation of the NAAQS that occurs after redesignation. The 
maintenance plan should identify the contingency measures to be 
adopted, a schedule and procedure for adoption and implementation, and 
a time limit for action by the state. A state should also identify 
specific indicators to be used to determine when the contingency 
measures need to be implemented. The maintenance plan must include a 
requirement that a state will implement all measures with respect to 
control of the pollutant that were contained in the SIP before 
redesignation of the area to attainment in accordance with section 
175A(d).
    In the February 24, 2009, submittal, Arkansas affirms that all 
programs instituted by the State and EPA will remain enforceable, and 
that sources are prohibited from reducing emissions controls following 
the redesignation of the area. The contingency plan included in the 
submittal provides a two-phase approach to tracking and triggering 
mechanisms to determine when contingency measures are needed and a 
process of developing and adopting appropriate control measures.
    Phase I--Potential increases in local emissions specifically, when 
the certified triennial emissions inventory for VOCs or NOX exceed the 
2006 base year attainment inventory by ten percent or more and at least 
one documentation of an exceedance of the 1997 ozone NAAQS at any 
nonattainment monitor in the area based on certified data during the 
most recent monitoring season.
    In the event this occurs, ADEQ will conduct an investigation into 
the cause to determine if the data are due to reporting errors or a 
non-recurring variance in the local emission profile. The investigation 
will be coordinated with the Memphis/Shelby County Health Department 
and the State of Tennessee as appropriate. If the investigation reveals 
the data are valid, ADEQ will expand voluntary programs and develop 
regulations to address the concerns. All regulatory programs will be 
implemented within 24 months and include a selection of measures shown 
in Table 8.