IV. Why Is EPA Taking These Actions?

On October 16, 2006, the VADEQ requested redesignation of the Hampton Roads Area to attainment for the 8hour ozone standard. On October 18, 2006, VADEQ submitted a maintenance plan for the Hampton Roads Area as a SIP revision, to ensure continued attainment of the 8 hour ozone NAAQS over the next 11 years, until 2018. Concurrently, Virginia is requesting that 8hour maintenance plan submittal supersede the 1hour maintenance plan requirements already in place and that the 8hour maintenance plan meet the requirement of CAA section 175A(b) with respect to the 1hour ozone maintenance plan update. EPA is proposing to approve the maintenance plan to fulfill the requirement of section 175A(b) for submission of a maintenance plan update eight years after the area was redesignated to attainment of the 1hour ozone NAAQS. EPA believes that such an update must ensure that the maintenance plan in the SIP provides maintenance of the NAAQS for a period of 20 years after the area is initially redesignated to attainment. EPA can propose approval because the maintenance plan, which demonstrates maintenance of the 8hour ozone NAAQS through 2018, also demonstrates maintenance of the 1hour ozone NAAQS through 2018.

VADEQ also submitted a 2002 baseyear inventory with its maintenance plan as a SIP revision on October 12, 2006 and supplemental to that submittal on November 20, 2006 and February 13, 2007, which is an applicable requirement for the Hampton Roads Area for purposes of redesignation. EPA has determined that the Hampton Roads Area has attained the 8hour ozone standard and has met the requirements for redesignation set forth in section 107(d)(3)(E).

V. What Would Be the Effect of These Actions?

Approval of the redesignation request would change the official designation of the Hampton Roads Area from nonattainment to attainment for the 8hour ozone NAAQS found at 40 CFR part 81. It would also incorporate into the Virginia SIP a 2002 baseyear inventory and a maintenance plan ensuring continued attainment of the 8hour ozone NAAQS in the Hampton Roads Area for the next 11 years, until 2018. The maintenance plan includes contingency measures to remedy any future violations of the 8hour NAAQS (should they occur), and identifies the NOX and VOC MVEBs for transportation conformity purposes for the years 2011 and 2018. These MVEBs are displayed in the following table:
Table 1.Motor Vehicle Emissions Budgets in Tons per Day (tpd) Year VOC NOX 2011.......................................... 37.846 50.387 2018.......................................... 27.574 31.890 VI. What Is EPA's Analysis of the Commonwealth's Request?

EPA is proposing to determine that the Hampton Roads Area has attained the 8hour ozone standard and that all other redesignation criteria have been met. The following is a description of how the VADEQ's October 16, 2006 (redesignation request), October 18, 2006 (maintenance plan and MVEBs), October 12, 2006 (baseyear emissions inventory), November 20, 2006 (supplement to baseyear inventory), and February 13, 2007 (second supplement to baseyear inventory) submittals satisfy the requirements of section 107(d)(3)(E) of the CAA. A. The Hampton Roads Area Has Attained the 8Hour Ozone NAAQS

EPA is proposing to determine that the Hampton Roads Area has attained the 8hour ozone NAAQS. For ozone, an area may be considered to be attaining the 8hour ozone NAAQS if there are no violations, as determined in accordance with 40 CFR 50.10 and Appendix I of Part 50, based on three complete, consecutive calendar years of qualityassured air quality monitoring data. To attain this standard, the 3year average of the fourthhighest daily maximum 8hour average ozone concentrations measured at each monitor, within the area, over each year must not exceed the ozone standard of 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 qualityassured in accordance with 40 CFR part 58, and recorded in the Air Quality System (AQS). The monitors generally should have remained at the same location for the duration of the monitoring period required for demonstrating attainment.

There are three ozone monitors in the Hampton Roads Area. As part of its redesignation request, Virginia referenced ozone monitoring data for the years 20032005 for the Hampton Roads Area. This data has been quality assured and is recorded in the AQS. The fourthhigh 8hour daily maximum concentrations, along with the threeyear averages are summarized in Table 2. The Hampton and SuffolkTCC monitoring sites had the highest 3year average of the fourth highest daily maximum 8 hour average and are therefore used to make air quality determinations. [[Page 18606]]
Table 2.Hampton Roads Area Fourth Highest 8Hour Average Values, Hampton Roads Monitors, Parts per Million (ppm) 3year Monitor AQS ID No. 2003 2004 2005 average Hampton......................... 516500004 0.083 0.074 0.078 0.078 SuffolkTCC.................... 518000004 0.083 0.074 0.077 0.078 SuffolkHolland................ 518000005 0.079 0.075 0.078 0.077 The average for the 3year period 20032005 is 0.078 ppm.

The air quality data for 20032005 show that the Hampton Roads Area has attained the standard with a design value of 0.078 ppm. The data collected at the Hampton Roads Area monitors satisfy the CAA requirement that the 3year average of the annual fourthhighest daily maximum 8hour average ozone concentration is less than or equal to 0.08 ppm. The VADEQ's request for redesignation for the Hampton Roads Area indicates that the data is complete and was quality assured in accordance with 40 CFR part 58. The VADEQ uses the AQS as the permanent database to maintain its data and quality assures the data transfers and content for accuracy. In addition, as discussed below with respect to the maintenance plan, VADEQ has committed to continue monitoring in accordance with 40 CFR part 58. In summary, EPA has determined that the data submitted by Virginia indicates that the Hampton Roads Area has attained the 8hour ozone NAAQS.
B. The Hampton Roads Area Has Met All Applicable Requirements Under Section 110 and Part D of the CAA and Has a Fully Approved SIP Under Section 110(k) of the CAA

EPA has determined that the Hampton Roads Area has met all SIP requirements applicable for purposes of this redesignation under section 110 of the CAA (General SIP Requirements) and that it meets all applicable SIP requirements under part D of Title I of the CAA, 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 proposed determinations, EPA ascertained which requirements are applicable to the Hampton Roads Area and determined that the applicable portions of the SIP meeting these requirements are fully approved under section 110(k) of the CAA. We note that SIPs must be fully approved only with respect to applicable requirements. The September 4, 1992 Calcagni memorandum (``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) with respect to the timing of applicable requirements. Under this interpretation, to qualify for redesignation, States requesting redesignation to attainment must meet only the relevant CAA requirements that came due prior to the submittal of a complete redesignation request. See also Michael Shapiro memorandum, September 17, 1993, and 60 FR 12459, 1246566 (March 7, 1995) (redesignation of DetroitAnn Arbor). 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. Section 175A(c) of the CAA. Sierra Club v. EPA, 375 F.3d 537 (7th Cir. 2004). See also 68 FR at 25424, 25427 (May 12, 2003) (redesignation of St. Louis).

This section also sets forth EPA's views on the potential effect of the Court's ruling in South Coast on this redesignation action. For the reasons set forth below, EPA does not believe that the Court's ruling alters any requirements relevant to this redesignation action so as to preclude redesignation, and does not prevent EPA from finalizing this redesignation. EPA believes that the Court's decision, as it currently stands or as it may be modified based upon any petition for rehearing that has been filed, imposes no impediment to moving forward with redesignation of this area to attainment, because in either circumstance redesignation is appropriate under the relevant redesignation provisions of the Act and longstanding policies regarding redesignation requests.

1. Section 110 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. The general SIP elements and requirements set forth in section 110(a)(2) include, but are not limited to the following:

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 transport of air pollutants in accordance with the NOX SIP Call, October 27, 1998 (63 FR 57356), amendments to the NOX SIP Call, May 14, 1999 (64 FR 26298) and March 2, 2000 (65 FR 11222), and the Clean Air Interstate Rule (CAIR), May 12, 2005 (70 FR 25162). However, 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 the designation of any one particular area in the State.

Thus, we do not believe that these requirements are applicable requirements for purposes of
[[Page 18607]]
redesignation. 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 Hampton Roads Area will still be subject to these requirements after it is redesignated. The section 110 and part D requirements, which are linked with a particular area's designation and classification, are the relevant measures to evaluate in reviewing a redesignation request. This policy is consistent with EPA's existing policy on applicability of conformity (i.e., for redesignations) and oxygenated fuels requirement. See Reading, Pennsylvania, proposed and final rulemakings (61 FR 53174, October 10, 1996), (62 FR 24826, May 7, 1997); ClevelandAkronLorain, Ohio final rulemaking (61 FR 20458, May 7, 1996); and Tampa, Florida, final rulemaking (60 FR 62748, December 7, 1995). See also the discussion on this issue in the Cincinnati redesignation (65 FR at 37890, June 19, 2000), and in the Pittsburgh redesignation (66 FR at 53099, October 19, 2001). Similarly, with respect to the NOX SIP Call rules, EPA noted in its Phase 1 Final Rule to Implement the 8hour Ozone NAAQS, that the NOX SIP Call rules are not ``an'' `applicable requirement' for purposes of section 110(1) because the NOX rules apply regardless of an area's attainment or nonattainment status for the 8hour (or the 1 hour) NAAQS.'' 69 FR 23951, 23983 (April 30, 2004).

EPA believes that section 110 elements not linked to the Area's nonattainment status are not applicable for purposes of redesignation. As explained later in this notice, two part D requirements applicable for purposes of redesignation under the 8hour standard became due prior to the submission of the redesignation request.

Because the Virginia SIP satisfies all of the applicable general SIP elements and requirements set forth in section 110(a)(2), EPA concludes that Virginia has satisfied the criterion of section 107(d)(3)(E) regarding section 110 of the Act.
2. Part D Nonattainment Requirements Under the 8Hour Standard

The Hampton Roads Area was classified a Subpart 2, marginal nonattainment area for the 8hour ozone standard. Sections 172176 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.

The Hampton Roads Area is classified as a Subpart 2, marginal nonattainment area. We do not believe that any part of the Court's opinion would require that this subpart 2 classification be changed upon remand to EPA. However, even assuming for present purposes that the Hampton Roads Area would become subject to a different classification under a classification scheme created in a future rule in response to the court's decision, that would not prevent EPA from finalizing a redesignation for this area. For the reasons set forth below, we believe that any additional requirements that might apply based on that different classification would not be applicable for purposes of evaluating the redesignation request.

This belief is based upon (1) EPA's longstanding policy of evaluating redesignation requests in accordance with only the requirements due at the time the request was submitted; and (2) consideration of the inequity of applying retroactively any requirements that might be applied in the future.

First, at the time the redesignation request was submitted, the area was classified under Subpart 2 and was required to meet the Subpart 2 requirements. Under EPA's longstanding interpretation of section 107(d)(3)(E) of the Clean Air Act, to qualify for
redesignation, states requesting redesignation to attainment must meet only the relevant SIP requirements that came due prior to the submittal of a complete redesignation request. September 4, 1992 Calcagni memorandum (``Procedures for Processing Requests to Redesignate Areas to Attainment'', Memorandum from John Calcagni, Director, Air Quality Management Division) See also Michael Shapiro Memorandum, September 17, 1993, and 60 FR 12459, 1246566 (March 7, 1995) (redesignation of DetroitAnn Arbor); Sierra Club v. EPA, 375 F.3d 537 (7th Cir. 2004), which upheld this interpretation. See, e.g, also 68 FR 25418, 25424, 25427 (May 12, 2003) (redesignation of St. Louis). At the time the redesignation request was submitted, the Hampton Roads Area was classified as a marginal area under Subpart 2 and thus only Subpart 2 marginal area requirements are applicable for purposes of

redesignation.

Moreover, it would be inequitable to retroactively apply any new SIP requirements that were not applicable at the time the request was submitted, but which might later become applicable. The D.C. Circuit has recognized the inequity in such retroactive rulemaking. See Sierra Club v. Whitman, 285 F.3d 63 (D.C. Cir. 2002), in which the D.C. Circuit upheld a District Court's ruling refusing to make retroactive an EPA determination of nonattainment that was past the statutory due date. Such a determination would have resulted in the imposition of additional requirements on the area. The Court stated: ``Although EPA failed to make the nonattainment determination within the statutory time frame, Sierra Club's proposed solution only makes the situation worse. Retroactive relief would likely impose large costs on the States, which would face fines and suits for not implementing air pollution prevention plans in 1997, even though they were not on notice at the time.'' Id. at 68. Similarly, here it would be unfair to penalize the area by applying to it for purposes of redesignation any additional requirements that were not in effect at the time it submitted its redesignation request, but that might apply in the future.

Two Subpart 2 requirements became due for the Hampton Roads Area under section 182(a) of the CAA prior to redesignationa 2002 base year inventory, and the emissions statement requirement pursuant to section 182(a)(3)(B). Virginia has in its approved SIP an approved emissions statement rule for the 1hour standard covering those portions of the 8hour nonattainment area that were part of the previous 1hour attainment area, which satisfies the emissions statement requirement for the 8hour standard. See 65 FR 21315 (April 21, 2000). Virginia recently submitted a rulemaking to expand the VOC and NOX Hampton Roads Emissions Control Area to include Gloucester County and Isle of Wight County. EPA approved this rulemaking on March 2, 2007 (72 FR 9441) and will become effective on April 2, 2007. Today, EPA is proposing to approve the 2002 baseyear inventory for the Hampton Roads Area, which was submitted on October 12, 2006, and supplemented on November 20, 2006 and February 13, 2007, concurrently with its maintenance plan, into the Virginia SIP. A detailed evaluation of Virginia's 2002 baseyear inventory for the Hampton Roads Area can be found in a Technical Support Document (TSD) prepared by EPA for this rulemaking. EPA has determined that the emission inventory and emissions statement requirements for the Hampton Roads Area have been satisfied.

EPA believes it is reasonable to interpret the general conformity and NSR requirements of part D as not requiring approval prior to [[Page 18608]]
redesignation. With respect to section 176, Conformity Requirements, section 176(c) of the CAA requires states to establish criteria and procedures to ensure that Federallysupported 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 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) since 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 (6th Cir. 2001), upholding this interpretation. See also 60 FR 62748 (December 7, 1995).

EPA has also determined that areas being redesignated need not comply with the requirement that a NSR program be approved prior to redesignation, provided that the area demonstrates maintenance of the standard without part D NSR in effect, because PSD requirements will apply after redesignation. The rationale for this position is described in a memorandum from Mary Nichols, Assistant Administrator for Air and Radiation, dated October 14, 1994, entitled, ``Part D NSR Requirements or Areas Requesting Redesignation to Attainment.'' Virginia has demonstrated that the Area will be able to maintain the standard without Part D NSR in effect in the Hampton Roads Area, and therefore, Virginia need not have a fully approved Part D NSR program prior to approval of the redesignation request. Virginia's SIPapproved PSD program will become effective in Hampton Roads upon redesignation to attainment. See rulemakings for Detroit, Michigan (60 FR at 1246768); ClevelandAkronLorrain, Ohio (61 FR at 20458, 2046970); Louisville, Kentucky (66 FR 53665, 53669 October 23, 2001); Grand Rapids, Michigan (61 FR at 31831, 3183437, June 21, 1996).

3. Requirements Under the 1Hour Standard

With respect to the 1hour standard requirements, the Gloucester County and Isle of Wight County portions of the Hampton Roads Area were designated Unclassifiable/Attainment under the 1hour standard and were never designated nonattainment for the 1hour standard. Therefore, there are no outstanding 1hour nonattainment area requirements these portions of the Hampton Roads Area would be required to meet. Thus, we find that the Court's ruling does not result in any additional 1hour requirements for purposes of redesignation.

The portion of the Hampton Roads Area consisting of the Cities of Chesapeake, Hampton, Newport News, Norfolk, Poquoson, Portsmouth, Suffolk, Virginia Beach, and Williamsburg, and the Counties of James City, and York, Virginia was an Attainment area subject to a Clean Air Act section 175A maintenance plan under the 1hour standard. The Court's ruling does not impact redesignation requests for these types of areas.

First, there are no conformity requirements that are relevant for redesignation requests for any standard, including the requirement to submit a transportation conformity SIP.\2\ Under longstanding EPA policy, EPA believes that it is reasonable to interpret the conformity SIP requirement as not applying for purposes of evaluating a 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. 40 CFR 51.390. See Wall v. EPA, 265 F.3d 426 (6th Cir. 2001), upholding this interpretation. See also 60 FR 62748 (Dec. 7, 1995) (Tampa, FL redesignation).
\2\ Clean Air Act section 176(c)(4)(E) currently requires States to submit revisions to their SIPs to reflect certain federal criteria and procedures for determining transportation conformity. Transportation conformity SIPs are different from the motor vehicle emissions budgets that are established in control strategy SIPs and maintenance plans.

Second, with respect to the three other antibacksliding provisions for the 1hour standard that the Court found were not properly retained, this portion of the Hampton Roads Area is an attainment area subject to a maintenance plan for the 1hour standard, and the NSR, contingency measure (pursuant to section 172(c)(9) or 182(c)(9)) and fee provision requirements no longer apply to an area that has been redesignated to attainment of the 1hour standard.

Thus the decision in South Coast should not alter requirements that would preclude EPA from finalizing the redesignation of this area. 4. Hampton Roads Has a Fully Approved SIP for Purposes of Redesignation

EPA has fully approved the Virginia SIP for the purposes of this redesignation. EPA may rely on prior SIP approvals in approving a redesignation request. Calcagni Memo, p. 3; Southwestern Pennsylvania Growth Alliance v. Browner, 144 F. 3d 984, 98990 (6th Cir. 1998), Wall v. EPA, 265 F. 3d 426 (6th Cir. 2001), plus any additional measures it may approve in conjunction with a redesignation action. See 68 FR at 25425 (May 12, 2003) and citations therein. The Hampton Roads Area was a 1hour ozone maintenance area at the time of its designation as a marginal 8hour ozone nonattainment area on April 30, 2004. As stated previously, two subpart 2 part D requirements became due for the Hampton Roads Area prior to redesignationa 2002 baseyear inventory, and the emissions statement requirement. VADEQ has submitted concurrently with its maintenance plan, a 2002 baseyear inventory as a SIP revision. In this action, EPA is proposing approval of this inventory. The emissions statement requirement for the entire Hampton Roads Area was recently fulfilled on March 2, 2007 (72 FR 9441). Because there are no outstanding SIP submission requirements applicable for the purposes of the redesignation of the Hampton Roads Area, the applicable implementation plan satisfies all pertinent SIP requirements.
C. The Air Quality Improvement in the Hampton Roads 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 the Commonwealth has demonstrated that the observed air quality improvement in the Hampton Roads Area is due to permanent and enforceable reductions in emissions resulting from implementation of the SIP, Federal measures, and other Stateadopted measures. Emissions reductions attributable to these rules are shown in Table 3.
[[Page 18609]]
Table 3.Total VOC and NOX Emissions for 2002 and 2005 in Tons per Day (tpd) Year Point Area * Nonroad Mobile Total Volatile Organic Compounds (VOC) 2002............................ 18.758 87.402 46.543 67.293 219.996 2005............................ 20.091 91.980 42.320 50.591 204.982 Diff (0205).................... +1.333 +4.578 4.223 16.702 15.014 Nitrogen Oxides (NOX) 2002............................ 91.403 57.961 31.002 93.844 274.210 2005............................ 62.536 55.207 30.208 78.169 226.120 Diff (0205).................... 28.867 2.754 0.794 15.675 48.090 * Area source category includes emissions from motor vehicle refueling.

Between 2002 and 2005, VOC emissions decreased by 15.014 tpd and NOX emissions decreased by 48.090 tpd because of permanent and enforceable measures implemented by the Commonwealth and the federal government. These reductions, and anticipated future reductions, are due to the following permanent and enforceable measures.
Programs Currently in Effect
(a) Tier 1;
(b) Tier 2;
(c) National Low Emission Vehicle (NLEV) Program; and
(d) NOX SIP Call.

EPA believes that permanent and enforceable emissions reductions are the cause of the longterm improvement in ozone levels and are the cause of the Area achieving attainment of the 8hour ozone standard. D. The Hampton Roads Area Has a Fully Approvable Maintenance Plan Pursuant to Section 175A of the CAA

In conjunction with its request to redesignate the Hampton Roads Area to attainment status, Virginia submitted a SIP revision to provide for maintenance of the 8hour ozone NAAQS in the Area for at least 11 years after redesignation. The Commonwealth is requesting that EPA approve this SIP revision as meeting the requirement of CAA 175A and 175A(b). Section 175A(a) was met with the October 18, 2006 submission of the maintenance plan, because it states that Hampton Roads will maintain the 8hour ozone NAAQS for at least 10 years after redesignation. Section 175A(b) was met with the October 18, 2006 submission of the maintenance plan, because it will replace the 1hour maintenance plan update requirement that was due 8 years after redesingation of Hampton Roads to attainment. Once approved, the maintenance plan for the 8hour ozone NAAQS will ensure that the SIP for Hampton Roads meets the requirements of the CAA regarding maintenance of the applicable 8hour ozone standard.

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(a), the plan must demonstrate continued attainment of the applicable NAAQS for at least 10 years after approval of a redesignation of an area to attainment. Section 175A(b) states that eight years after redesignation from nonattainment to attainment, the State must submit a revised maintenance plan demonstrating that attainment will continue to be maintained for the next 10year period following the initial 10year 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 8hour 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 dated September 4, 1992, provides additional guidance on the content of a maintenance plan. An ozone maintenance plan should address the following provisions:
(a) An attainment emissions inventory;
(b) A maintenance demonstration;
(c) A monitoring network;
(d) Verification of continued attainment; and
(e) A contingency plan.
Analysis of the Hampton Roads Area Maintenance Plan
(a) Attainment inventoryAn attainment inventory includes the emissions during the time period associated with the monitoring data showing attainment. VADEQ determined that the appropriate attainment inventory year is 2005. That year establishes a reasonable year within the threeyear block of 20032005 as a baseline and accounts for reductions attributable to implementation of the CAA requirements to date. The 2005 inventory is consistent with EPA guidance and is based on actual ``typical summer day'' emissions of VOC and NOX during 2005 and consists of a list of sources and their associated emissions.

To develop the NOX and VOC base year emissions inventories, VADEQ used the following approaches:
(i) Point source emissions were developed using the latest version of EPA's Economic Growth Analysis System (EGAS 5.0).
(ii) Area source emissions were also developed using growth factors from EGAS 5.0 and then applied to the 2002 Area source inventory. (iii) Mobile nonroad emissions were developed using EPA's NONROAD 2005 model. The NONROAD 2005 model estimates fuel consumption and emissions of total hydrocarbons, carbon monoxide, nitrogen oxides, sulfur oxides, and particulate matter for all nonroad mobile source categories except for aircraft, locomotives, and commercial marine vessels (CMV).
(iv) Mobile onroad source emissions were calculated using EPA's MOBILE6.2 mobile source inventory model. The Virginia Department of Transportation (VDOT) provided daily vehicle miles traveled (DVMT), average speed data for each road type by jurisdiction, and annual growth rates that were used to forecast DVMT into the future. Also, the Virginia Department of Motor Vehicles provided registration data that was specific to each jurisdiction. Mobile source emission projections include the National Low Emission Vehicle Program (NLEV), the 2004 Tier 2 and Low Sulfur Gasoline Rule, the 2004 and 2007 HeavyDuty Diesel Vehicle Rules, and the 2006 Low Sulfur Diesel Rule. In
[[Page 18610]]
addition, James City, York, Chesapeake, Hampton, Newport News, Norfolk, Poquoson, Portsmouth, Suffolk, Virginia Beach, and Williamsburg were modeled with Phase II Reformulated Gasoline (RFG) while Gloucester and Isle of Wight were modeled with conventional gasoline fuel.

More detailed information on the compilation of the 2002, 2005, 2011, and 2018 inventories can found in the Technical Appendices, which are part of VADEQ's October 18, 2006 submittal.
(b) Maintenance DemonstrationOn October 18, 2006, the VADEQ submitted a maintenance plan as required by section 175A of the CAA. The Hampton Roads maintenance plan shows maintenance of the 8hour ozone NAAQS by demonstrating that future emissions of VOC and NOX will not exceed the attainment year 2005 emissions levels throughout the Hampton Roads Area through the year 2018. A maintenance demonstration need not be based on modeling. See Wall v. EPA, supra; Sierra Club v. EPA, supra. See also 66 FR at 5309953100; 68 FR at 2543032.

Tables 4 and 5 specify the VOC and NOX emissions for the Hampton Roads Area for 2005, 2011, and 2018. The VADEQ chose 2011 as an interim year in the maintenance demonstration period to demonstrate that the VOC and NOX emissions are not projected to increase above the 2005 attainment level during the time of the maintenance period.
Table 4.Total VOC Emissions for 20052018 (tpd) 2005 VOC 2011 VOC 2018 VOC Source category emissions emissions emissions Point........................................................... 20.091 23.280 26.700 Area \1\........................................................ 91.980 100.960 112.790 Mobile \2\...................................................... 50.591 37.846 27.574 Nonroad......................................................... 42.320 33.912 31.315

Total....................................................... 204.982 195.998 198.379 \1\ Includes vehicle refueling emissions and the benefits of selected local controls (Stage I, CTG RACT, and open burning). Also includes site/project specific emissions estimates and projections. \2\ Includes transportation provisions.
Table 5.Total NOX Emissions for 20052018 (tpd) 2005 NOX 2011 NOX 2018 NOX Source category emissions emissions emissions Point........................................................... 62.536 69.333 75.241 Area \1\........................................................ 55.207 56.974 60.105 Mobile \2\...................................................... 78.169 50.387 31.890 Nonroad........................................................ 30.208 29.116 23.093

Total....................................................... 226.120 205.810 190.329 \1\ Includes selected local controls (open burning). Also includes site/project specific emissions estimates and projections.

\2\ Includes transportation provisions.

Additionally, the following programs are either effective or due to become effective and will further contribute to the maintenance demonstration of the 8hour ozone NAAQS:

Currently in Effect:

Additionally, the following programs are in place and either effective or are due to become effective:

Lastly, to further improve air quality and to provide room for industrial and population growth while maintaining emissions in the area to less than 2005 levels, the Commonwealth of Virginia has initiated rulemaking to implement the following programs:

Based on the comparison of the projected emissions and the attainment year emissions along with the additional measures, EPA concludes that VADEQ has successfully demonstrated that the 8hour ozone standard should be maintained in the Hampton Roads Area. (c) Monitoring NetworkThere are three monitors measuring ozone in the Hampton Roads Area. VADEQ will continue to operate its current air quality monitors (located in the Hampton Roads Area), in accordance with 40 CFR part 58.
(d) Verification of Continued AttainmentIn addition to maintaining the key elements of its regulatory program, the Commonwealth will acquire ambient and source emission data to track attainment and maintenance. The Commonwealth will track the progress of the maintenance demonstration by periodically updating
[[Page 18611]]
the emissions inventory. This tracking will consist of annual and periodic evaluations. The annual evaluation will consist of checks on key emissions trend indicators as they actually emission update of stationary sources, the Highway Performance Monitoring System (HPMS) vehicle miles traveled data reported to the Federal Highway Administration, and other growth indicators. These indicators will be compared to the growth assumptions used in the plan to determine if the predicted versus the observed growth remains relatively constant. The Commonwealth will also develop and submit periodic (every three years) emission inventories prepared under EPA's Consolidated Emission Reporting Regulation (40 CFR 51, subpart A), beginning in 2005. (e) The Maintenance Plan's Contingency MeasuresThe 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 ensure that the Commonwealth will promptly correct a violation of the NAAQS that occurs after redesignation. The maintenance plan should identify the events that would ``trigger'' the adoption and implementation of a contingency measure(s), the contingency measure(s) that would be adopted and implemented, and the schedule indicating the time frame by which the state would adopt and implement the measure(s).

The ability of the Hampton Roads Area to stay in compliance with the 8hour ozone standard after redesignation depends upon VOC and NOX emissions in the Area remaining at or below 2005 levels. The Commonwealth's maintenance plan projects VOC and NOX emissions to decrease and stay below 2005 levels through the year 2018. The Commonwealth's maintenance plan outlines the procedures for the adoption and implementation of contingency measures to further reduce emissions should a violation occur.

The Commonwealth's maintenance plan lays out situations where the need to adopt and implement a contingency measure to further reduce emissions would be triggered. Those situations are as follows: (i) An actual increase of the VOC or NOX emissions exceed the regional emissions budgets, which would be identified or predicted through the development of the comprehensive periodic tracking inventoriesThe maintenance plan states that the VADEQ will monitor the observed growth rates for VMT, population, and point source VOC and NOX emissions on a yearly basis which will serve as an early warning indicator of the potential for a violation. The plan also states that comprehensive tracking inventories will also be developed every 3 years using current EPAapproved methods to estimate emissions, concentrating on areas identified in the less rigorous yearly evaluations as being potential problems. If the regional emissions budget for VOC or NOX is exceeded, the following control strategies will be implemented as follows:

The following schedule for adoption, implementation and compliance applies to the contingency measures concerning nonCTG RACT requirements. It would also apply to the imposition of the area source VOC regulations if those regulations had not already been implemented due to other triggers or provisions of the maintenance plan.

The maintenance plan adequately addresses the five basic components of a maintenance plan: Attainment inventory, maintenance demonstration, monitoring network, verification of continued attainment, and a contingency plan. EPA believes that the maintenance plan SIP revision submitted by Virginia for the Hampton Roads area meets the requirements of section 175A of the Act.
VII. Are the Motor Vehicle Emissions Budgets Established and Identified in the Hampton Roads Maintenance Plan Adequate and Approvable? A. What Are the Motor Vehicle Emissions Budgets?

Under the CAA, States are required to submit, at various times, control strategy SIPs and maintenance plans in ozone areas. These control strategy SIPs (i.e., RFP SIPs and attainment demonstration SIPs) and maintenance plans identify and establish MVEBs for certain criteria pollutants and/or their precursors to address pollution from onroad mobile sources. In the maintenance plan, the MVEBs are termed ``onroad mobile source emission budgets.'' Pursuant to 40 CFR part 93 and 51.112, MVEBs must be established in an ozone maintenance plan. An MVEB is the portion of the total allowable emissions that is allocated to highway and transit vehicle use and emissions. An MVEB serves as a ceiling on emissions from an area's planned transportation system. The MVEB concept is further explained in the preamble to the November 24, 1993, transportation conformity rule (58 FR 62188). The preamble also describes how to establish and revise the MVEBs in control strategy SIPs and maintenance plans.

Under section 176(c) of the CAA, new transportation projects, such as the construction of new highways, must ``conform'' to (i.e., be consistent with) the part of the State's air quality plan that addresses pollution from cars and trucks. ``Conformity'' to the SIP means that transportation activities will not cause new air quality violations, worsen existing violations, or delay timely attainment of or reasonable progress towards the NAAQS. If a transportation plan does not ``conform,'' most new projects that would expand the capacity of roadways cannot go forward. Regulations at 40 CFR part 93 set forth EPA policy, criteria, and procedures for demonstrating and ensuring conformity of such transportation activities to a SIP.

When reviewing submitted ``control strategy'' SIPs or maintenance plans containing MVEBs, EPA must affirmatively find the MVEB contained therein ``adequate'' for use in determining transportation conformity. After EPA affirmatively finds the submitted MVEB is adequate for transportation conformity purposes, that MVEB can be used by state and federal agencies in determining whether proposed transportation projects ``conform'' to the SIP as required by section 176(c) of the CAA. EPA's substantive criteria for determining ``adequacy'' of a MVEB are set out in 40 CFR 93.118(e)(4).

EPA's process for determining ``adequacy'' consists of three basic steps: Public notification of a SIP submission, a public comment period, and EPA's adequacy finding. This process for determining the adequacy of submitted SIP MVEBs was initially outlined in EPA's May 14, 1999 guidance, ``Conformity Guidance on Implementation of March 2, 1999, Conformity Court Decision.'' This guidance was finalized in the Transportation Conformity Rule Amendments for the ``New 8Hour Ozone and PM2.5 National Ambient Air Quality Standards and Miscellaneous Revisions for Existing Areas; Transportation Conformity Rule AmendmentsResponse to Court Decision and Additional Rule Change'' on July 1, 2004 (69 FR 40004). EPA consults this guidance and follows this rulemaking in making its adequacy determinations.

The MVEBS for the Hampton Roads Area are listed in Table 1 of this document for 2011 and 2018, and are the projected emissions for the on road mobile sources plus any portion of the safety margin allocated to the MVEBs (safety margin allocation for 2011 and 2018 only). These emission budgets, when approved by EPA, must be used for transportation conformity determinations.

B. What Is a Safety Margin?

A ``safety margin'' is the difference between the attainment level of emissions (from all sources) and the projected level of emissions (from all sources) in the maintenance plan. The attainment level of emissions is the level of emissions during one of the years in which the area met the NAAQS. The following example is for the 2018 safety margin: Hampton Roads first attained the 8hour ozone NAAQS during the 2003 to 2005 time period. The Commonwealth used 2005 as the year to determine attainment levels of emissions for Hampton Roads. The total emissions from point, area, mobile onroad, and mobile nonroad sources in 2005 equaled 204.982 tpd of VOC and 226.120 tpd of NOX. The VADEQ projected emissions out to the year 2018 and projected a total of 198.379 tpd of VOC and 190.329 tpd of NOX from all sources in Hampton Roads. The safety margin for 2018 would be the difference between these amounts, or 6.603 tpd of VOC and 35.791 tpd of NOX. The emissions up to the level of the attainment year including the safety margins are projected to maintain the Area's air quality consistent with the 8hour ozone NAAQS. The safety margin is the extra emissions reduction below the attainment levels that can be allocated for emissions by various sources as long as the total emission levels are maintained at or below the attainment levels. Table 7 shows the safety margins for the 2011 and 2018 years.
Table 7.2011 and 2018 Safety Margins for Hampton Roads VOC emissions NOX emissions Inventory year (tpd) (tpd) 2005 Attainment....................... 204.982 226.120 2011 Interim.......................... 195.998

FOR FURTHER INFORMATION CONTACT Amy Caprio, (215) 814-2156, or by e- mail at caprio.amy@epa.gov.