section 172( e) and the CAA's redesignation provisions, we believe that Congress intended these areas to continue to implement requirements that applied in the area for the 1

hour NAAQS. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 24 For purposes of the preamble to this rulemaking, whenever we state that a State must make the demonstration required under section 110( l) to modify its SIP, we also mean that the State must make the required demonstration under section 193 to the extent the affected area is designated nonattainment and the SIP requirement the State 95 2. Discretionary control measures This discussion of discretionary measures also addresses enforceable commitments approved into the SIP.

( Section VI. C. 3. a. ii. of proposed rule, see 68 FR 32821, and Section VI. C. 3. a. v. of proposed rule; see 68 FR 32822;

Section 51.905( d) of draft regulatory text)

a. Background. Many approved SIPs contain control measures that are not specified under subpart 2 for the area, but that the State chose to adopt as part of the demonstration of attainment or part of the ROP requirement for the 1 hour NAAQS. For these kinds of measures, we proposed that States retain the discretion they now have to modify these requirements in their SIPs. For purposes of the 1 hour standard, States may currently revise or remove those requirements so long as they make a demonstration consistent with section 110( l) that such removal or modification would not interfere with attainment of or progress toward the 1 hour ozone NAAQS ( or any other applicable requirement of the CAA). 24 For purposes of the 8 hour standard, the same STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 is modifying was a control requirement in effect or required to be in effect prior to November 15, 1990.

96 discretion to modify a SIP would apply except the State would need to make the demonstration required by section 110( l) with respect to the 8 hour standard, not the 1 hour standard. See 68 FR 32821 for an example of how this would work.

We also proposed that States remain obligated to meet enforceable commitments approved into a SIP to the same extent as if they were adopted measures ( 68 FR 32822). This includes enforceable commitments to perform a mid course review. The only way a State may modify or remove such a commitment is through a SIP revision making the required demonstration under section 110( l).

b. Summary of Final Rule. We are adopting the approach we set forth in our proposed rule. A State may revise or remove discretionary control measures ( including enforceable commitments) contained in its SIP for the 1 hour standard so long as the State demonstrates consistent with section 110( l) that such removal or modification will not interfere with attainment of or progress toward the 8 hour ozone NAAQS ( or any other applicable requirement of the CAA). Under the rule, States remain obligated to meet any SIP approved STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 97 commitment to perform a mid course review. These commitments do not bind the States to take any specific action in response to the results of the mid course review.

The EPA anticipates that rather than using these reviews to ensure areas meet the 1 hour standard ( which will have been revoked), States and EPA can use these reviews to ensure progress is being made consistent with needs for the 8 hour standard.

Note, however, that since general provisions for modifying or removing control measures in a SIP are already provided in the statute ( sections 110( l) and 193), we do not believe there is a need to have a duplicative provision in this final rule. Therefore, even though the draft regulatory text contained such a provision ( section 51.905( d)), the final rule does not contain that provision.

c. Comments and Responses Several commenters supported the proposal regarding discretionary control measures. Several commenters believed that States should not be held to commitments to submit the mid course review required under their 1 hour SIP. Several commenters objected to the provision in draft regulatory text for allowing " relaxations" of the SIP under sections 110( l) and 193 of the CAA. Several commenters believed that STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 98 the rule should clarify that revisions could be made to control requirements under section 51.905( a) in addition to those not covered under section 51.905( a).

RESPONSE: Sections 110( l) and 193 allow States to modify the discretionary controls in their SIPs if the provisions of those sections are met. While we believe it is important to prevent backsliding consistent with the statutory provisions, we do not believe it is appropriate to further restrain the discretion Congress granted to States in determining the appropriate mix of controls in the SIP.

We believe that a State may revise discretionary controls approved in its SIP as long as it meets the criteria specified in sections 110( l) and 193. We believe the anti backsliding provisions of Sections 110( l) and 193 will prevent the adverse effects envisioned by the commenter.

3. Measures to address growth. ( Section VI. C. 3. a. iii of proposed rule; see 68 FR 32821; sections 51.900( f) and 51.905( a)( 1) of final rule.)

a. Background. In general, the SIP provisions in the CAA include two provisions to address growth   nonattainment NSR and conformity. We discuss conformity for all areas in a later section.

For areas designated nonattainment for the 1 hour STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 99 standard at the time of designation for the 8 hour standard and that are designated nonattainment for the 8 hour standard, we proposed in the June 2, 2003 notice that the major source applicability cut offs and offset ratios for nonattainment NSR that applied for an area's 1 hour classification continue to apply.

b. Summary of Final Rule. We are adopting the approach set forth in our proposed rule. For areas designated nonattainment for the 1 hour standard at the time of designation for the 8 hour NAAQS and that are designated nonattainment for the 8 hour standard, the major source applicability cut offs and offset ratios for the area's 1

hour classification continue to apply. For example, if an area is classified moderate under the 8 hour standard, but was classified severe under the 1 hour standard at the time of the 8 hour designations, the area would remain subject to an offset ratio of 1.3: 1 and a major source threshold of 25 tons/ year. ( We discuss the geographic area that remains subject to this obligation in a later section.)

For those areas that have not yet met the 1 hour clean air goal ( or have met the goal, but have not yet been redesignated to attainment and therefore allowed to stop implementing their 1 hour nonattainment NSR program), we STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 100 believe it is appropriate to require the area to continue to comply with its current program. For the reasons stated above, we do not believe that Congress intended areas to revise their SIPs to weaken obligations where EPA has promulgated a revised, more stringent NAAQS. We discuss the timing in a later section.

c. Comments and Responses Several commenters supported the proposed rule. Other commenters believed the 1 hour standard should not be revoked at all, and therefore there would not be a need for the anti backsliding provision regarding NSR. One commenter noted that the language in the draft regulatory text is based upon the date of revocation of the 1 hour ozone NAAQS,

which is at least one year later than that specified in the proposed rule. The date of revocation is also highly uncertain compared to the date of designation, which is driven by the Consent Decree. The Draft Regulatory Text therefore conflicts with the proposed rule language. The commenter prefers use of the date of designation for these and other applicable requirements.

RESPONSE: The regulatory text has been revised to key the requirement from the effective date of designation for the 8 hour standard. We address the issue of the revocation STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 25 In this rulemaking, we use " ROP" to refer to the rate of progress requirement for the 1 hour standard and " RFP" to refer to both the rate of progress requirement under subpart 2 and the reasonable further progress requirement under subpart 1 for the 8 hour ozone standard.

101 of the 1 hour standard elsewhere in this notice and do not repeat it here.

4. Planning SIPs.

a. Outstanding ROP Obligation. This was discussed in Section VI. C. 3. a. iv of proposal ( see 68 FR 32822) and addressed in section 51.905( a)( 1) of the draft regulatory text.

( i) Background. In the June 2, 2003 notice, we proposed that States remain obligated to address separately 1 hour ROP requirements that do not overlap with RFP obligations for the 8 hour NAAQS. 25 Where outstanding ROP and RFP obligations overlap, the area need not submit a separate ROP plan for the 1 hour standard but must show that the 8 hour ROP plan is no less stringent than the 1 hour ROP requirement. For ROP provisions already adopted into the SIP, we proposed that the State may remove or revise control measures needed to meet the ROP milestone if such control measures were discretionary ( i. e., not mandated by subpart 2 for the area's 1 hour classification), as discussed above, STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 102 and the State makes a demonstration under section 110( l)

that the revision will not interfere with meeting the 1 hour ROP and 8 hour RFP goals.

( ii) Summary of Final Rule. We are adopting the approach set forth in our proposed rule for areas designated nonattainment for the 8 hour NAAQS and designated nonattainment for the 1 hour NAAQS at the time areas are designated for the 8 hour NAAQS. States remain obligated to meet the CAA mandated ROP emission reduction targets that applied for the 1 hour standard, but discretionary measures adopted to meet those targets may be modified, if the State makes the necessary showing under section 110( l).

In addition, we are providing further clarification regarding how this obligation applies. Areas that have an outstanding obligation for an approved 1 hour ROP SIP for one or more of the ROP periods ( e. g., 1999 2002, 2002 2005,

2005 2007) must still develop and submit to EPA ( if they have not already done so) all outstanding 1 hour ROP plans.

Where a 1 hour ROP obligation overlaps with an 8 hour RFP requirement, the State's 8 hour RFP measures can be used to satisfy the 1 hour ROP obligation.

The State may choose to show that both the 8 hour and 1 hour ROP obligations are met through a single 8 hour plan STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 103 submittal. To prevent backsliding, the State must ensure that the 8 hour RFP emission plan is at least as stringent as the 1 hour ROP emission target, for the year in which 1

hour ROP must be met. The State may do this by first establishing an RFP emission target for the entire 8 hour ozone nonattainment area, for the 1 hour ROP target year. If the 8 hour RFP emission target for the 8 hour area for the same period is more stringent than the 1 hour ROP emission target for the 1 hour area ( assuming the 8 hour area includes the entire 1 hour area), the State is not obligated to submit a separate 1 hour ROP plan, but can rely solely on the 8 hour RFP plan and emission target to demonstrate that the 1 hour target will be met. The State must ensure that the emission target will be met for the same period as for 1 hour ROP ( e. g., 2003 2005). The State may rely on any control measure to meet both ROP for the 1 hour standard and RFP for the 8 hour standard. Appendix A provides an example of how this might work.

As indicated in the June 2, 2003 proposal ( 68 FR 32835), we proposed that this policy would remain effective under the 8 hour ozone NAAQS, and we therefore intend to apply this policy in implementing this final rule for areas that achieve the 8 hour standard. Thus, if an area attains STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 104 the 8 hour ozone standard, under the Agency's " Clean Data Policy," EPA may waive the 1 hour RFP obligation for the area based on a determination that the area has attained the 8 hour standard. Under that policy, the State will not be subject to the 1 hour RFP requirement for so long as the area remains in attainment with the 8 hour standard. ( EPA will address the applicability of the Clean Data Policy for 8 hour ozone nonattainment areas in Phase 2 of the implementation rule.)

We believe that there is ambiguity in the statute regarding whether areas should remain subject to the requirement to submit planning SIPs, such as the 1 hour ROP plans. Unlike control obligations, we do not believe there is as strong an argument that Congress intended areas to continue to submit planning SIPs for a standard that EPA has determined is no longer necessary to protect public health.

Section 172( e), which applies when EPA relaxes a NAAQS, only requires EPA to ensure that control measures are no less stringent than they were for the more stringent NAAQS that has been replaced. It does not indicate a Congressional intent that areas remain obligated to plan for and meet a revised NAAQS. However, both attainment demonstrations and ROP plans result in the adoption of control obligations. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 105 And, if EPA determined that these planning requirements did not apply at all, areas currently designated nonattainment for the 1 hour standard that have not met these obligations might be subject to less stringent controls than would have otherwise applied.

For purposes of ROP, the exercise of calculating the reductions necessary to meet ROP is relatively simply.

Moreover, as provided above, even if the State must calculate ROP separately for the 1 hour and 8 hour standards, it may still rely on one or more of the same control measures to meet both those obligations.

Additionally, we believe that most of the areas with an outstanding 1 hour ROP obligation will be able to demonstrate that the 8 hour RFP targets for the same time period will be more stringent and thus will not be required to prepare a separate 1 hour ROP plan. Finally we note that States have already submitted and EPA has already approved 1 hour ROP plans for most 1 hour nonattainment areas. Thus,

the anti backsliding provisions regarding the continued obligation to adopt and submit 1 hour ROP plans will affect only a handful of areas. For these reasons, we are adopting a regulation that requires areas that remain nonattainment for the 1 hour standard at the time of revocation of the 1 STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 106 hour standard to continue to achieve the level of ROP reductions mandated by Congress under the CAA for that standard.

( iii) Comments and Responses Comments on the June 2, 2003 notice Few commenters submitted comments on the portion of the proposed rule discussing the anti backsliding requirements applicable to 1 hour ROP. Several commenters generally opposed any continued planning obligations under the 1 hour standard, but did not raise specific concerns with respect to ROP. Similarly, a number of other commenters opposed revocation of the 1 hour standard and urged retention of all 1 hour planning and control obligations; but again, these commenters did not raise concerns specific to the proposed anti backsliding approach for ROP.

One commenter addressing section 51.905( a)( 1)( iii) of the draft text argued that States should have the ability to modify ROP measures if it can be demonstrated that they are not needed for purposes of meeting requirements under the 8

hour standard or if measures are no longer appropriate due to updated technical information regarding emissions inventory and control strategy effectiveness. Another commenter objected to retaining the 1 hour ROP requirement, STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 107 primarily because areas recently reclassified to a higher classification would have a continuing obligation for ROP even if they were not required to develop an RFP plan under the 8 hour standard. Another commenter believed the 1 hour ROP requirement should only be required where it is demonstrated to be needed for attainment of the 8 hour standard.

RESPONSE: As provided above, we believe the best interpretation of the Act is that areas must continue to meet obligations that applied for their 1 hour classifications. The ROP obligation results in control obligations that will help the area attain the 8 hour standard. Further, if States believe adopted controls are not the best fit for the 8 hour standard, the State retains full discretion to revise those controls so long as the revision doesn't interfere with the ROP milestones.

Without this provision, an area with an unmet obligation to prepare submit and implement a rate of progress plan under the 1 hour standard could experience backsliding by being released from a requirement to continue progress toward attainment of the ozone standard during the interim period prior to implementation of the SIP required for the 8 hour NAAQS. In other words, if the 1 hour STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 108 standard were not revoked, the area would have been required to continue to ensure emissions would be reduced to levels designed to ensure progress toward meeting the 1 hour standard. If the final rule contained no provision comparable to section 51.905( a)( 1)( i), achievement of those emissions reductions could be delayed. Because we are transitioning to a more stringent and protective air quality standard we see no reason why there should be provisions that would provide less protection to public health.

b. Unmet attainment demonstration obligations ( Section VI. C. 3. a. iv of proposal; see 68 FR 32822; section 51.905( a)( 1)( ii) of the draft rule)

( i) Background. Most areas designated nonattainment for the 1 hour ozone standard have fully approved attainment demonstrations for the 1 hour standard. Because there are so few areas without approved attainment demonstrations, in the proposed rule we identified the two types of situations of which we were aware and solicited comment on how to handle those situations. First, there are a few areas that do not have a fully approved attainment demonstration because the area has not acted in accordance with the time lines provided under the Act. The second situation is an area which has a future obligation to submit an attainment STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 109 demonstration. In general, these are areas that, over the past several years, have been reclassified ( i. e., " bumped up") to a higher classification. In the preamble to the proposal, we discussed the policy reasons that would support retention of the obligation to submit an attainment demonstration and the policy reasons that would counsel against retention of that obligation. 68 FR 32822. For both these groups of areas, we solicited comment on whether to retain the obligation to develop a 1 hour attainment demonstration. In addition, we solicited comment on two alternatives that would address many of the policy concerns we noted.

Alternative 1 would require that areas with a current or past due obligation to submit a new or revised attainment demonstration instead be required to submit a SIP revision that would obtain an advance increment of local emission reductions toward attainment of the 8 hour ozone standard within a specified, short term time frame; 5 percent and 10 percent were suggested possibilities for the increment.

Under Alternative 2, areas with a current or past due obligation to submit a 1 hour attainment demonstration would be required to submit their 8 hour ozone attainment demonstration early in lieu of being required to submit a STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 110 1 hour attainment demonstration. The draft regulatory text was developed using the first alternative, and used a 10 percent increment.

( ii) Summary of Final Rule. In the final rule, we are allowing the States to choose among three options that are tailored after the approaches addressed in the proposed rule. Thus, rather than establishing one mandatory approach, we are adopting a rule that will allow States to choose any one of the following three options:

° Option 1. Submit a 1 hour attainment demonstration.

° Option 2. Submit, no later than one year after the effective date of the 8 hour designations, an early increment of progress plan toward the 8 hour standard which provides:

° A 5 percent increment of reduction from the 2002 emissions baseline ( NOx and/ or VOC). The control measures for achieving this increment must be in addition to measures ( or enforceable commitments to measures) in the SIP as of the effective date of designation and in addition to national or regional measures. ( The State can take credit for this increment of reduction toward its RFP requirement under the 8 hour standard.) STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 26The amount of which will depend on the ROP option in the final rule and the classification of the area.

111 ° For achievement of the emission reductions within 2 years after submittal ( i. e., 3 years after designation).

° Option 3. Submit an early 8 hour ozone attainment demonstration SIP one year after the effective date of designation for the 8 hour standard that:

° Demonstrates attainment of the 8 hour standard by the area's attainment date ° Provides for 8 hour RFP consistent with the area's classification out to the area's attainment date.

° Ensures that the first segment of RFP26 between the end of 2002 and the end of 2008 is achieved early   by the end of 2007.

With respect to Option 2, the final rule specifies a 2002 baseline year for calculating the early increment of progress whereas the draft regulatory text did not provide a specific baseline year.

As noted above in the ROP section, we believe the statute is unclear regarding the need for States to address planning for a standard no longer needed to protect public STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 112 health. Unlike planning for ROP, preparing an attainment demonstration involves complex modeling and analyses that can be resource intensive both in terms of man hours and cost. We don't believe it is appropriate or necessary to mandate that States perform the attainment demonstration for a standard that is not needed to protect public health. But we also do not believe it is appropriate to waive in total this obligation in light of the need to ensure continued emissions reductions to protect public health. We are adopting this approach because it provides maximum flexibility to States that have outstanding attainment demonstration obligations while continuing to obtain in a timely fashion many or all of the emission reductions that should occur under those obligations, effecting an orderly transition to planning under the 8 hour standard. In addition, we do not believe it is equitable to relieve these areas of this obligation where other areas have already adopted controls to meet these obligations and will not be able to modify or remove such controls unless the State can demonstrate that such action is consistent with section 110( l).

Thus, in balancing Congressional intent to ensure no backsliding, equitable treatment of all areas, the need for STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 113 areas to begin planning for the 8 hour standard and the limited planning resources that State have available, we believe the best approach is to provide States with several alternatives, each of which will achieve additional and/ or early emission reductions consistent with reductions that would have been achieved through a 1 hour attainment demonstration SIP. The State may choose the option that is least burdensome in light of activities already performed.

For example, States with a 1 hour attainment demonstration that is past due or is due in the next several months may have already made significant progress in developing a 1

hour attainment demonstration SIP. Thus, these State may choose the first option. We are aware that one or more States have already begun the process of developing 8 hour attainment demonstrations for some 1 hour nonattainment areas. These States may choose to submit an early 8 hour attainment demonstration SIP. Other areas, which have not yet made significant progress on 1 hour or 8 hour attainment planning may wish to reserve more time to the attainment demonstration process, which can involve complex modeling,

and thus choose to achieve an early increment of progress.

For the second option available to States, we chose five   rather than 10   percent as the amount of reduction. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 114 Under this Option, States must achieve the 5 percent emission reduction from local controls ( not currently required by the SIP) and within 3 years of designation. In light of the quick timeframe in which to achieve the reductions following designations and the limitation that such reductions cannot be from regional or national controls or from measures already in the SIP, we concluded that 10 percent was unduly burdensome. The States that choose this option will need to identify and adopt appropriate controls within a 1 year timeframe and require sources to implement the controls within a short time thereafter. These limitations will restrict the control choices available to States. In addition, because of the limited timeframe for adoption and submission of the controls to EPA, we do not believe it is reasonable to require the State to obtain a level of reduction that would force the States to concentrate its resources on the early ROP reduction rather than on an 8 hour attainment plan. However, because the State will not be able to rely on national or regional controls, we are confident that the 5 percent requirement will achieve the anti backsliding goal.

Finally, as with the 1 hour ROP requirement, we note that EPA may waive the 1 hour attainment demonstration STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 27Memorandum of May 10, 1995, " RFP, Attainment Demonstration, and Related Requirements for Ozone Nonattainment Areas Meeting the Ozone National Ambient Air Quality Standard," from John S. Seitz, Director, Office of Air Quality Planning and Standards. Available at: http:// www. epa. gov/ ttn/ oarpg/ t1/ memoranda/ clean15. pdf.

115 requirement for areas based on a determination that the area has attained the 8 hour standard. EPA's Clean Data Policy27 provides that if EPA has determined that an area has attained the 1 hour standard, it will not be obligated to submit a 1 hour attainment demonstration for so long as it maintains the 1 hour standard. Thus, extending this policy to the 8 hour standard, if EPA determines that an area has attained the 8 hour ozone standard before the time the area is obligated to make a submission under this portion of EPA's 8 hour implementation regulations, EPA would waive this requirement for so long as the area remains in attainment with the 8 hour standard.

( iii) Comments and Responses Several commenters advocated retaining the planning obligations under the 1 hour standard expressing the belief that momentum will be lost in implementing controls if these obligations are not retained. In general, most of these commenters also opposed revocation of the 1 hour standard and believed Congress intended the 1 hour standard to be STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 116 planned for and met. Some commenters opposed retaining the attainment demonstration requirements under the 1 hour standard after the standard is revoked on the basis that State resources are limited and should be focused on developing plans for implementing the 8 hour rather than the 1 hour standard. A few commenters favored the alternative of requiring an early plan with an advance increment of emission reductions toward progress of the 8 hour standard in lieu of the attainment demonstration SIP revision. A few other commenters favored the alternative of requiring States to submit an early attainment demonstration SIP for the 8

hour standard.

Only one commenter believed that 10 percent was the appropriate amount under Alternative 1 for an advance increment of progress; several others opposed 10 percent,

claiming that it appeared to be punitive, that there was no technical support for that amount, and that it may be more than what was needed for attainment of the 8 hour standard.

Some commenters recommended that exceptions be made for any area that made good faith efforts to develop and submit its plan, such as those with a submitted and approved plan that may have been challenged and overturned by a court.

RESPONSE: We have designed the final rule such that an STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 117 area without an approved attainment demonstration or ROP plan would still be required to submit and implement a ROP plan and an attainment demonstration or substitute plan under the 1 hour standard. We believe this approach will avoid backsliding and will continue progress toward attainment of the 8 hour ozone standard.

We believe that areas that have not met their planning obligations under the 1 hour standard   if relieved of that obligation after the 1 hour standard is revoked   would provide emission reductions on a more protracted time schedule than areas that had met their 1 hour standard planning obligations. For example, an area that is classified severe 15 for the 1 hour standard would have to obtain RFP reductions and any additional reductions needed for attainment by the end of 2005, whereas if that same area is moderate under the 8 hour standard, it would not be required to obtain reductions under the RFP provisions until 2008 and additional reductions for attainment by some time in 2009. We believe that considerations of cost are secondary to this concern in these situations. We believe that the provisions of the final rule   by offering three alternative means of meeting the 1 hour attainment demonstration obligation   allow sufficient flexibility for STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 118 a State in these circumstances to choose the most appropriate means to overcome this deferral of protection.

Section 51.905( a)( 2): 8 Hour NAAQS Nonattainment/ 1 Hour NAAQS Maintenance Area In the June 2003 proposal, we discussed the requirements for areas designated as attainment for the 1

hour NAAQS with a maintenance plan at the time of designation for the 8 hour NAAQS in the same sections discussing the requirements for areas designated nonattainment for the 1 hour NAAQS at the time of 8 hour designations. However, in the draft regulatory provisions,

we created a separate subparagraph addressing these areas.

Below, we indicate briefly where the obligations for these areas   i. e., maintenance areas at the time of designation,

are the same as for areas designated nonattainment for the 1 hour standard at the time of 8 hour designations. We discuss in more detail where the obligations differ.

1. Mandatory Control Measures. ( Section VI. C. 3. a. i. of proposed rule; see 68 FR 32821; sections 51.900( f) and 51.905( a)( 2) of draft rule.)

a. Background. In the June 2003 proposal, we proposed that all areas designated nonattainment for the 8 hour standard and that were nonattainment or maintenance for the 1 hour STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 28In order to redesignate these areas to attainment, EPA had to determine these areas had met all obligations under Part D. See CAA Section 107( d)( 3)( E).

119 standard would be required to continue to implement mandatory measures adopted into the approved SIP. We did not distinguish between areas designated nonattainment for the 1 hour standard at the time of designation for the 8

hour standard and areas that are maintenance for the 1 hour standard at the time of designation for the 8 hour standard.

However, in the draft regulatory text, we created a separate provision for maintenance areas because these areas do not have an outstanding obligation to adopt mandatory control obligations for the 1 hour standard. 28 Thus, the draft regulatory provision for maintenance areas did not address the future adoption of controls; it simply would require areas to continue to implement the applicable requirements ( as defined in the regulatory text) approved into the SIP.

We also provided in the June 2003 proposal and the draft regulatory text that if a maintenance area had previously shifted a mandatory control measure to the contingency provisions, the area would not be required to begin implementation of that measure based on the 8 hour nonattainment designation. However, the measure would need STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 120 to remain as a contingency measure for the area and could not be removed from the SIP.

b. Final Rule. We are adopting the approach we took in the proposal and the draft regulatory text. Areas that are maintenance for the 1 hour standard at the time of 8 hour designations and are designated nonattainment for the 8 hour NAAQS, must continue to implement mandatory control requirements ( i. e., " applicable requirements") that have been approved into the SIP. However, since maintenance areas do not have any outstanding obligation to adopt mandatory control obligations for the 1 hour standard, the provision only addresses implementation, not adoption. In addition, this section recognizes that maintenance areas had the flexibility to move mandatory controls to the contingency measures portion of their maintenance plan. The area would not be required to implement these measures unless it is required to do so for the area's classification for the 8 hour NAAQS. However, the measures would need to remain as contingency measures and could not be removed from the SIP.

We are adopting the requirement that 1 hour Maintenance areas are required to continue to implement mandatory controls for the same reasons we provided with respect to 8 STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 121 hour Nonattainment/ 1 hour Nonattainment areas above. With respect to mandatory measures that the State has moved to the contingency portion of the maintenance plan, we do not believe that Congress intended to require areas to begin implementing such measures again based on the promulgation of a revised NAAQS unless required based on the area's classification for the revised NAAQS. These areas have fully complied with the process that Congress established   attainment of the ( then existing) NAAQS and redesignation to attainment for that NAAQS based on a plan demonstrating that the area will maintain the standard. While we believe these areas should not " backslide" from existing control levels,

we do not believe that for purposes of the 8 hour NAAQS they should be required to begin implementing once more measures that the State has chosen to place in its contingency measures provision.

2. Discretionary Control measures a. Background.

b. Final Rule. As with discretionary control measures for 8 hour Nonattainment/ 1 hour Nonattainment areas, maintenance areas for the 1 hour standard that are designated nonattainment for the 8 hour ozone NAAQS will retain the discretion to modify any discretionary control measures upon STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 29 If an area located in the Ozone Transport Region was redesignated to attainment, section 184( b)( 2) of the CAA required it to retain a nonattainment NSR program. In addition, it is possible that one or more areas still has a nonattainment NSR program in place because of the way the State wrote the SIP.

122 a demonstration under section 110( l). We are not promulgating regulatory text because, as described above,

sections 110( l) and 193 of the CAA govern such SIP revisions.

3. Measures to address growth. ( Section VI. C. 3. a. iii of proposed rule; see 68 FR 32821; sections 51.900( f) and 51.905( a)( 1) of final rule.)

a. Background. In the proposal, we recognized that 1 hour maintenance areas generally are subject to the prevention of significant deterioration ( PSD) program and are no longer implementing the nonattainment NSR program for their previous 1 hour ozone designation and classification. 29 For areas where the NSR program no longer applies under the SIP,

we proposed that the areas would not need to revert back to the NSR program they had for purposes of the 1 hour standard. The proposal provided examples of how this would work. 68 FR 32821.

b. Summary of Final Rule. We are adopting the approach we proposed. If an area has been redesignated to attainment STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 123 for the 1 hour standard as of the effective date of the 8

hour nonattainment designation and is no longer required to implement a nonattainment NSR program, the area will not be required to revert back to the program it had for purposes of the 1 hour ozone standard. The final rule addresses this by requiring only that the State continue to implement obligations in the approved SIP. As noted in the June 2003 proposal, this provision only addresses the area's obligation with respect to the 1 hour NSR requirements; it does not affect the requirements for the area's 8 hour nonattainment NSR program ( which will be addressed in Phase 2 or a separate rule).

Unlike the mandatory control obligations discussed above, Congress did not intend the nonattainment NSR program to continue to apply to most areas once they are redesignated to attainment. Rather, such areas are subject to the PSD program. For areas that have met the clean air goals for the 1 hour standard, we see no reason to require such area to revert back to their 1 hour NSR program. These areas will be required to implement the nonattainment NSR program that applies based on their classification for the 8 hour ozone NAAQS.

4. Planning SIPs. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 124 a. Background. In the June 2003 proposal, we did not discuss maintenance areas separate from areas designated nonattainment for the 1 hour NAAQS at the time of designation as nonattainment for the 8 hour NAAQS. However,

the preamble discussion focused on areas with an outstanding obligation to submit a 1 hour ROP or attainment plan and the obligation to ensure that the ROP percentage reduction obligations in the approved SIP are achieved. Maintenance areas for the 1 hour standard do not have an outstanding obligation to submit ROP or attainment plans for the 1 hour standard. Thus, the draft regulatory text did not include language similar to that in 51.905( a)( ii) and ( iii) for maintenance areas. The draft regulatory text did reflect ROP as an applicable requirement for maintenance areas.

b. Final Rule.

We are adopting the approach taken in the draft regulatory text. In redesignating an area to attainment,

EPA must conclude that the area has met all requirements applicable under section 110 and part D. Thus, maintenance areas do not have continuing progress and attainment demonstration requirements. The final rule does not establish requirements for maintenance areas related to outstanding attainment demonstration and ROP plans. The STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 125 final rule does identify the ROP percent reduction requirement as an applicable requirement. However, we note that the ROP periods for areas redesignated to attainment for the 1 hour standard have already passed and thus any revision to the SIP should not affect ROP reductions for the periods required for the 1 hour standard.

5. Comments and Responses One commenter believed that 1 hour maintenance counties designated nonattainment under the 8 hour standard should not have to submit updates to the 1 hour maintenance plan,

since they will be developing 8 hour attainment plans that will subsume the requirements of the maintenance plan previously in effect.

RESPONSE: The rule provides that after the 1 hour ozone standard is revoked, areas are relieved of responsibilities to submit updates to their 1 hour maintenance plans. The State may submit a revision to the SIP to remove the provisions that require the update to the maintenance plan.

One commenter noted that draft Section 51.905( a)( 2)

would limit shifting of an applicable requirement to the contingency measure portion of an area's maintenance plan.

Under the proposal, a State may only make such a shift prior STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 126 to the revocation of the 1 hour NAAQS; States may only make subsequent shifts by satisfying the requirements of Section 110( l) of the CAA. The commenter believes that this criterion for shifting measures to the maintenance plan is more stringent and burdensome than the requirements in Section 175A of the CAA for maintenance plans. In the alternative, the commenter recommends that in lieu of the showing required by Section 110( l), that States, instead, be allowed to substitute a control measure with equivalent emissions reductions for the measures they propose to remove from their plan.

RESPONSE: We do not believe this recommendation is supportable. The requirement is more stringent than requirements in section 175A of the Act precisely because the area in question would no longer be a maintenance area but rather nonattainment under the 8 hour standard, and therefore any revision to the control requirements in the SIP require a showing under section 110( l), not merely that the revision obtain equivalent emission reductions.

One commenter noted that in section 51.905( a)( 2), the clause "... except to the extent required under its 8 hour obligations..." could be interpreted to imply that contingency measures in the 1 hour maintenance plan become STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 127 8 hour measures by default. The commenter suggests that the last sentence of this section be replaced with the following language:

" Mandatory measures in the area's 1 hour SIP must be implemented in its 8 hour SIP; however, obligations that were shifted to contingency measures prior to revocation of the 1 hour NAAQS for the area, must be in the 8 hour SIP, but may remain contingency measures,

unless the measures are required to be implemented by the Act."

RESPONSE: The final rule reflects this recommended language change.

Section 51.905( a)( 3): 8 Hour Attainment or Unclassifiable/

1 Hour Nonattainment 1. Mandatory control obligations. ( Section VI. C. 3. b. of proposal see 68 FR 32823; section 51.905( a)( 3)( i) of final rule)

a. Background. The proposal noted that the issue of what obligation remains with respect to mandatory control measures approved into the SIP or required under the CAA is based on the CAA's requirements for maintenance plans. We proposed that these obligations would remain in place but in a later section of the preamble proposed options as to when STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 128 this obligation would no longer apply. These two options were: 1) when the area attains the 1 hour NAAQS, or ( 2) when the area attains the 8 hour NAAQS.

b. Summary of Final Rule.

We are adopting an approach consistent with our proposed rule. As we discuss later in this preamble, we have determined that mandatory control obligations will no longer apply once an area attains the 8 hour standard.

Thus, because these areas are attaining the 8 hour standard,

the State may request that obligations under the applicable requirements of section 51.900( f) be shifted to contingency measures once the 1 hour standard is revoked, consistent with sections 110( l) and 193 of the CAA. However, the State cannot remove the obligations from the SIP.

Because these areas are in attainment with the healthbased standard, we believe that Congress   as with areas redesignated from nonattainment to attainment   did not intend the areas to retain these controls as implemented measures if the area can demonstrate maintenance without the controls. As with areas redesignated, the rule provides that the State cannot remove the measures from the SIP, but rather may move them to the contingency measures portion of the SIP. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 30If an area located in the Ozone Transport Region was redesignated to attainment, section 184( b)( 2) of the CAA 129 2. Discretionary control obligations. ( Section VI. C. 3. b. iii. of proposal see 68 FR 32823; section 51.905( d)

of draft regulatory text)

Areas designated nonattainment for the 1 hour standard that are designated attainment for the 8 hour ozone NAAQS will retain the discretion to modify any discretionary controls upon a demonstration under section 110( l).

However, such controls must remain in the SIP as contingency measures. We are not promulgating regulatory text because,

as described above, sections 110( l) and 193 of the CAA govern such SIP revisions. As with mandatory measures, we look to the maintenance plan provision of section 175A to see what Congress' intent may have been for these areas.

Because these areas were nonattainment for the 1 hour NAAQS,

we believe Congress intended them to retain the measures in the SIP, but could shift them to contingency measures if the area demonstrates it will maintain the 8 hour standard if the measure is no longer implemented.

3. Measures to address growth.

a. Background. The proposal explained that NSR applies only in nonattainment areas. 30 Since these areas would be STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 required it to retain a nonattainment NSR program. In addition, it is possible that one or more areas still has a nonattainment NSR program in place because of the way the State wrote the SIP.

130 designated attainment for the 8 hour standard   the only ozone standard that exists for the area once the 1 hour standard is revoked   they would be subject PSD, not NSR,

once the 1 hour standard is revoked.

b. Summary of Final Rule. We are adopting the approach we set forth in our proposed rule for areas designated attainment for the 8 hour NAAQS and designated nonattainment for the 1 hour NAAQS at the time of designation for the 8

hour standard. After the 1 hour standard is revoked, the CAA requires such areas to comply with PSD, not NSR. ( The States may need to modify their SIPs so that it provides for PSD rather than NSR in such areas.) We do not see a basis for mandating that such areas retain a nonattainment NSR program and do not believe that Congress intended such a result. As an initial matter, once the 1 hour standard is revoked, these areas are meeting the only ozone standard that is in place. Congress specified that PSD shall apply in areas not designated nonattainment ( section 161 if the CAA). We also note that we have never interpreted section 175A of the CAA to mandate that nonattainment NSR be STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 31Memorandum from Mary Nichols to Regional Air Division Directors dated October 14, 1994, entitled " Part D New Source Review ( part D NSR) Requirements for Areas Requesting Redesignation to Attainment."

131 retained as a contingency measure in the SIP after an area is redesignated from nonattainment to attainment because we do not interpret NSR to be a control measure. ( See, e. g.,

May 12, 2003; 68 FR 25436.)

Note that for these areas, the NSR provisions may be removed from the SIP and need not be shifted to contingency measures. 31 c. Comments and Responses Some commenters believed that the 1 hour standard should remain in effect, and therefore NSR would continue to apply until the area attains the 1 hour standard and is redesignated to attainment for that standard regardless of the area's status for the 8 hour standard. Other commenters generally agreed with the proposal.

One commenter believed there was a conflict between the June 2, 2003 notice and the draft regulatory text concerning the timing of the 1 hour NSR obligation. The draft section 51.905( a)( 1) provision would apply for areas designated nonattainment for the 1 hour NAAQS at the time of revocation of the 1 hour NAAQS, but the June 2, 2003 notice provision STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 132 would apply to areas designated nonattainment for the 1 hour standard at the time of designation of the 8 hour NAAQS.

The commenter recommended that the rule be based on the date of designation for the 8 hour standard.

RESPONSE: We address the broader legal and policy issues regarding revocation of the 1 hour standard in the revocation section of this rule.

We agree there was a conflict in the draft regulatory text on this matter, and the final rule language ( section 51.905( a)( 1)) reflects a change to indicate that after the 1 hour standard is revoked, areas that were nonattainment for the 1 hour standard at the time of 8 hour designation would continue to have the 1 hour obligation apply.

4. Planning SIPs. ( Section VI. C. 3. b( ii) of proposed rule;

see 68 FR 32823)

a. Background. In the June 2, 2003 proposed rule, we proposed that any outstanding SIP planning requirements ( ROP plans and attainment demonstrations) that applied for purposes of the 1 hour standard would not continue to apply to areas designated attainment for the 8 hour NAAQS for as long as they continue to maintain the 8 hour NAAQS. If such an area violates the 8 hour NAAQS prior to having an approved maintenance plan meeting the requirements of STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 133 section 110( a)( 1) the obligation to have a 1 hour attainment demonstration and ROP plan would once again apply in the same manner that they apply in areas designated nonattainment for the 8 hour ozone NAAQS.

The draft regulatory text ( section 51.905( a)( 3))

contained specific provisions addressing the obligation for an area designated attainment for the 8 hour NAAQS that subsequently violates the 8 hour standard prior to having an approved maintenance plan under section 110( a)( 1). If the area was required to and does not have an approved attainment demonstration or ROP plan for the 1 hour standard, the State would be required to submit a plan providing for a 10 percent emission reduction as a substitute for the attainment demonstration and to adopt and submit any outstanding ROP emission reductions.

b. Summary of Final Rule. We are adopting our proposal with some modification. As an initial matter, section 51.905( a)( 3) now only addresses areas designated nonattainment for the 1 hour standard at the time EPA designates areas for the 8 hour standard. We have created a new section 51.905( a)( 4) which addresses areas that are maintenance areas for the 1 hour standard at the time we designate areas for the 8 hour standard. That section STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 134 ( i. e., establishing requirements for areas that are maintenance areas for the 1 hour standard at the time of designation for the 8 hour standard and designated nonattainment for the 8 hour standard) is discussed below.

An area that is designated nonattainment for the 1 hour standard at the time of designation for the 8 hour standard and is designated attainment for the 8 hour standard will not be required to develop and submit outstanding attainment demonstration and ROP plans for the 1 hour standard for so long as the area continues to maintain the 8 hour NAAQS.

However, if the area violates the 8 hour NAAQS prior to having an approved 8 hour maintenance plan under section 110( a)( 1), the area will be required to submit a SIP revision to address outstanding ROP and attainment demonstration plans as follows.

( i) ROP Plans. For an outstanding 1 hour ROP plan,

the State must submit a SIP providing for any outstanding ROP and the three year periods for achieving those reductions will begin January 1 of the year following the 3

year period on which EPA bases its determination. For example, if an area was required to and does not have an approved SIP providing for a 9% reduction in emissions from 1996 1999, the obligation to have such a SIP is deferred STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 135 unless the area violates the 8 hour standard prior to having an approved maintenance plan for the 8 hour standard. If EPA determines in August 2007 that the area violated the 8 hour standard based on ambient air quality data from 2004 2006 and at that time the area does not have an approved maintenance plan for the 8 hour standard, the area will be required to submit a SIP providing for a 9% reduction in emissions for the three year period of January 2007

December 2009. The State may rely on national and regional controls for purposes of meeting this increment of reduction and the 9% should be calculated using the 1990 baseline.

( The 1 hour ROP requirement is calculated from a 1990 baseline, not a 2002 baseline, as is the 8 hour RFP requirement.) We have clarified the language in the final regulation to make clear that the requirement to submit the plan for additional emission reductions applies only to the extent that an area had not met its prior planning obligations. For example, if an area was classified as serious for the 1 hour standard and had an approved 15% ROP plan and an approved 9% ROP plan for 1996 1999, then the area does not have any outstanding ROP obligation that must be met under this provision. However, if the same area only had an approved 15% ROP plan, but not an approved 9% ROP STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 136 plan for 1996 1999, then the area has an outstanding 9% ROP plan for the 19996 1999 period. If the State had submitted the ROP plan to EPA, but EPA had not yet acted on the submission, the State may notify EPA that it wishes to rely on the previously submitted SIP or it may elect to submit a new or revised SIP.

We believe this approach makes sense as it ensures that the level of emission reduction that the area was required to achieve, but was not yet enforceable under the SIP, will be achieved expeditiously after a violation of the 8 hour standard occurs.

( ii) Attainment Demonstration. For an outstanding 1

hour attainment demonstration, the final rule requires the State to either: ( 1) submit an 8 hour maintenance plan that addresses the violation and demonstrates maintenance through EPA approved modeling; or ( 2) submit a plan to achieve a 3 percent increment of progress within 3 years after the EPA determines the area has violated the standard. The 3 percent increment of progress must be in addition to measures ( or enforceable commitments to measures) in the SIP at the time of the effective date of designation and in addition to national or regional measures.

This approach differs from both the June 2003 proposal STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 137 and the draft regulatory text in that we do not establish the precisely the same requirement for these areas that we establish for areas designated nonattainment for the 8 hour NAAQS. For areas designated nonattainment for the 8 hour NAAQS, section 51.905( a)( ii) provides three options for the State. The first option available is that States may choose to submit their 1 hour SIP. If such an area, subsequent to designation under the 8 hour standard, experiences a violation of the 8 hour standard, we do not believe it makes good policy sense for the area at that time to spend resources to develop a plan to achieve the 1 hour standard ( which is likely to have been revoked by that time), when the area will already be in the process of developing the section 110( a)( 1) maintenance plan for the area discussed elsewhere in this preamble. We believe there will be few if any areas in this situation that would experience a violation much above the level of the 8 hour standard since such areas have recently been attaining that standard.

The second and third options available to areas designated nonattainment for the 8 hour NAAQS are analogous but not identical to the two options we provide for areas designated attainment for the 8 hour NAAQS. Both types of areas are provided with the option of achieving a specified STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 138 increment of progress. For areas designated nonattainment for the 8 hour NAAQS, we established an increment of 5 percent and for those designated attainment for the 8 hour NAAQS, we established a 3 percent increment. In general, we believe that those areas initially designated attainment for the 8 hour NAAQS will have a less significant 8 hour problem   these areas tend to record values within a few parts per million of the standard. Thus, since the increment of progress is limited to controls not already adopted into the SIP or required by federal or regional controls, the 5 percent reduction requirement would likely be excessive for purposes of addressing that small deviation from the standard.

The third option available to areas designated nonattainment for the 8 hour NAAQS is to submit an early 8

hour attainment demonstration. Since areas designated attainment for the 8 hour standard are not required to develop attainment demonstrations, it did not make sense to carry this option over. Rather, we determined it made more sense to have the area address the violation in the context of the obligation that it does have, i. e., to develop a maintenance plan for the 8 hour standard. Thus, for these areas, we created the option of performing a more rigorous STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 139 maintenance demonstration   a demonstration based on EPAapproved modeling.

c. Comments and Responses.

Some commenters on draft regulatory text objected to continuing the obligation for areas to submit ROP plans and/ or attainment demonstrations for the 1 hour standard after the 1 hour standard is revoked. Some of the comments reflected the fact that the regulatory text may have been unclear regarding what the requirement and which areas were affected.

RESPONSE: We have designed the final rule such that an area with an unmet planning obligation would still be required to submit and implement a rate of progress plan and an attainment demonstration ( or substitute plan) under the 1 hour standard if the area violates the 8 hour standard before it has an approved maintenance plan. These are areas that have historically had an ozone problem and, in general,

are close to the 8 hour standard. Consistent with our Clean Data Policy, we do not believe these planning obligations should apply for so long as the area is in attainment with the standard. Once these areas have an approved 100( a)( 1)

maintenance plan with contingency measures, that plan will address future violations of the 8 hour standard. However, STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 140 until that plan is in place, we believe that Congress would have intended these requirements to still have significance if the area violates the health based standard.

The final regulatory text was modified to clarify that the provision applies to areas that do not have approved ROP plans and/ or attainment demonstrations under the 1 hour standard and that violate the 8 hour NAAQS before having an approved 8 hour maintenance plan under section 110( a)( 1).

5. Maintenance Plans for the 8 hour NAAQS. ( Section VI. C. 3. b( iii) of proposed rule; see 68 FR 32823; Section 51.905( a)( 3)( iii) of draft regulatory text)

a. Background In the June 2003 proposal, we proposed that areas designated attainment for the 8 hour NAAQS and designated nonattainment for the 1 hour NAAQS on or after November 15,

1990, must adopt and submit a maintenance plan consistent with section 110( a)( 1) within 3 years of designation as attainment for the 8 hour NAAQS. The maintenance plan should provide for continued maintenance of the 8 hour standard for 10 years following designation for the 8 hour NAAQS and must include contingency measures. Areas with approved 1 hour maintenance plans under section 175A would be able to modify those maintenance plans consistent with their obligation to STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 141 have a maintenance plan for the 8 hour NAAQS under section 110( a)( 1). Such areas could remove from their maintenance SIPs ( a) the obligation to submit a maintenance plan for the 1 hour standard 8 years after approval of their initial 1

hour maintenance plan; and ( b) the requirement to implement contingency measures upon a violation of the 1 hour ozone standard.

The draft regulatory text reflected the description in the June 2003 proposal.

b. Summary of Final Rule We are adopting the approach we proposed. However, as noted above, we have now created separate subsections in the rule addressing areas that were designated nonattainment for the 1 hour NAAQS at the time of designation for the 1 hour NAAQS and areas that were maintenance areas for the 1 hour standard at the time of designation for the 8 hour NAAQS.

Section 51.905( a)( 3)( iii) applies only to areas designated nonattainment for the 1 hour NAAQS at the time of designation for the 8 hour NAAQS. Section 51.905( a)( 4)( ii)

establishes the same requirement for areas that are maintenance for the 1 hour NAAQS at the time of designation for the 8 hour standard. Under these two provisions, areas designated attainment for the 8 hour NAAQS and designated STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 142 nonattainment for the 1 hour NAAQS ( 51.905( a)( 3)( iii)) or that are maintenance areas for the 1 hour NAAQS ( 51.905( a)( 4)( ii)) at the time of designation for the 8 hour NAAQS must adopt and submit a maintenance plan consistent with section 110( a)( 1) within 3 years of designation as attainment for the 8 hour NAAQS. The maintenance plan should provide for continued maintenance of the 8 hour standard for 10 years following designation for the 8 hour NAAQS and should include contingency measures. We provide additional detail below regarding maintenance areas for the 1 hour standard.

Section 110( a)( 1) requires all areas to demonstrate that they will attain and maintain the relevant NAAQS. Most of the areas addressed by this provision of the regulation have historically had problems meeting and remaining in attainment of the ozone standard. We think it is important for States to ensure that these areas will continue to have clean air so that the health of citizens will be protected.

c. Comments and Responses The majority of commenters who addressed this issue in comments on June 2, 2003 proposal did not support the section 110( a)( 1) maintenance plan requirement. Some commenters believed the 1 hour standard should remain in STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 143 effect and with it any existing 1 hour SIP requirements,

including section 175A maintenance plan requirements ( which would require conformity determinations). One comment objected to the proposed requirement, alleging the requirement was unnecessary and not required. Two commenters agreed with the requirement.

In commenting on the draft regulatory text one commenter supported this provision. One commenter recommended that we provide more specific guidance on preparation of section 110( a)( 1) maintenance plans and also not require modeling for them. Two commenters objected to maintenance plans under section 110( a)( 1) because they would not require conformity ( as would maintenance plans under section 175A) for areas that currently have maintenance plans under the 1 hour standard. The commenters believed the maintenance planning should be done under section 175A.

Another commenter believed that section 110( a)( 1) of the CAA requires neither contingency measures nor a 10 year plan;

the commenter suggested that the section 110( a)( 1)

maintenance plan merely be a continuation of the provisions of the existing maintenance plan.

RESPONSE: Because the 1 hour standard would be revoked,

the requirements of section 175A would not apply to these STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 144 areas ( areas initially designated attainment for the 8 hour standard but that were designated nonattainment for the 1

hour standard at the time of enactment of the 1990 CAA Amendments.) Section 175A applies to redesignations, not to initial designations. After the 1 hour standard is revoked,

we believe that an area   that was previously designated nonattainment for the 1 hour standard or was designated attainment with a maintenance plan   and that initially is designated attainment for the 8 hour ozone standard, should be required to demonstrate maintenance only for the 8 hour standard at that point. The area was not " redesignated"

attainment for the 8 hour standard, and therefore the section 175A maintenance plan requirement does not apply.

We believe that the section 110( a)( 1) maintenance provisions   as required in section 51.905   will provide adequate assurance of maintenance of the standard. EPA always retains the authority to require a State that fails to maintain the standard to revise its SIP to provide additional maintenance measures or to redesignate the area nonattainment and require an attainment demonstration.

We do not agree with commenters that opposed a provision requiring a maintenance plan under section 110( a)( 1) for these areas. We do believe that the Act STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 145 requires that SIPs continue to provide for maintenance of the applicable standard under section 110( a)( 1). Because these areas have historically experienced ozone problems and generally are close to violating the 8 hour standard, we believe it is prudent to require a demonstration of how they will maintain the 8 hour standard.

Section 51.905( a)( 4): 8 Hour Attainment/ 1 Hour Attainment with Maintenance Plan As noted above, in the preamble to the proposed rule,

EPA addressed in the same section 1 hour nonattainment areas and 1 hour maintenance areas that are designated nonattainment for the 8 hour standard. Comments on the proposed regulatory text noted that section 51.905( a)( 3)

only addressed 8 hour attainment areas that were designated nonattainment for the 1 hour ozone standard and not areas that were maintenance for that standard. Thus, the draft rule did not address all aspects of the proposal since it did not include provisions for areas that are maintenance for the 1 hour standard at the time of designations.

We considered revising paragraph 51.905( a)( 3) to include 1 hour maintenance areas. However, that subsection included certain requirements not relevant for 1 hour maintenance areas, such as requirements concerning STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 146 outstanding attainment demonstration and ROP plans. Thus,

in the final rule, we created section 51.905( a)( 4) to apply to areas designated attainment for the 8 hour standard and that were maintenance areas for the 1 hour standard at the time of designation for the 8 hour standard.

1. Obligations in an approved SIP. ( 51.905( a)( 4)( i)).

This subsection is identical in structure to section 51.905( a)( 3)( i). Our reasons are explained in our discussion of section 51.905( a)( 3)( i), above.

2. Maintenance plan. ( 51.905( a)( 4)( ii). As provided above in the discussion of section 51.905( a)( 3)( iii), we are adopting in our final rule our proposed interpretation regarding maintenance plans for areas designated nonattainment for the 1 hour NAAQS on or after November 15,

1990 ( i. e., areas that remain designated nonattainment for the 1 hour NAAQS as well as maintenance areas for the 1 hour NAAQS at the time of designation for the 8 hour NAAQS).

Specifically, these areas must adopt a maintenance plan under section 110( a)( 1) within three years of designation for the 8 hour NAAQS. The provision for maintenance areas is the same as for areas designated nonattainment for the 1

hour standard. However, for maintenance areas, section 51.905( e), discussed below, cross references this provision STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 147 and addresses the relationship between the 1 hour maintenance plan and the 8 hour maintenance plan.

Our reasons for adopting this provision are discussed above. Although these areas already have maintenance plans,

those plans only address maintenance of the 1 hour standard.

It is important for these areas to ensure that they have a plan addressing maintenance of the 8 hour standard. These areas may evaluate their existing plan and demonstrate how it will ensure maintenance of the 8 hour standard, or may modify their existing plan, or may adopt a new plan, as appropriate.

Comment: One commenter argued that it makes little sense to require the State to continue to expend the effort and resources to update and extend these maintenance plans. The commenter questioned why a newly designated marginal area under the 8 hour standard be exempt from implementation plan requirements, while an area previously nonattainment for the 1 hour standard, but now in attainment for both standards be required to continue with 8 additional years of maintenance plan requirements.

RESPONSE: The final rule ( section 51.905( a)( 4)) clarifies that for these areas ( areas that are initially designated attainment for the 8 hour standard but were attainment areas STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 148 under the 1 hour standard with approved maintenance plans)

that they are relieved of the requirement to update their maintenance plan under section 175( A), but must submit a maintenance plan under section 110( a)( 1) that provides for maintenance for 10 years. It should be noted that marginal areas under the 8 hour standard are not " exempt" from implementation plan requirements; they are still subject to nonattainment new source review and conformity requirements,

for instance. Furthermore, if a marginal area does not attain the NAAQS by its attainment date, the Act requires that the area be bumped up in classification, which would require the area to submit a revised SIP with an attainment demonstration and including control measures required under subpart 2 for the area's new classification.

Section 51.905( b): Does attainment of the ozone standard affect the obligations under paragraph ( a) of this section?

( Section VI. C. 4 of proposed rule; see 68 FR 32824; section 51.905( b) of draft rule)

1. Background In the June 2, 2003 proposed rule, we proposed two options for when the State would no longer be required to continue implementing SIP approved control obligations required for an area's 1 hour classification. At that time, STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 149 these requirements could be relegated to the contingency measures portion of the SIP if the State demonstrated that implementation of the controls was not necessary to attain or maintain the 8 hour NAAQS ( consistent with section 110( l)). For simplification, we refer to this as the time control obligations may be shifted to the contingency measures. We clarified that the term " control obligations"

was intended to refer to the obligations which we determined would continue to apply under the preceding sections of the proposal, including the NOx transport rules. Under Option 1, control obligations could be shifted to contingency measures when the area achieves the level of the 1 hour ozone standard ( even if the area has not yet attained the 8 hour standard). Under Option 2, control obligations could be shifted to contingency measures once the area attains and is redesignated to attainment for the 8 hour NAAQS ( regardless of when, if ever, the area attains the 1 hour standard). The draft regulatory text was developed using Option 1 ( when the area achieves the level of the 1 hour ozone standard).

2. Summary of Final Rule We are adopting Option 2   control obligations an area is required to retain in the approved SIP for an area's 1 STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 150 hour classification must continue to be implemented under the SIP until the area attains and is redesignated to attainment for the 8 hour standard. At that time, the State may relegate such controls to the contingency measure portion of the SIP if the State demonstrates in accordance with section 110( l) that doing so will not interfere with maintenance of the 8 hour NAAQS or any other applicable requirement of the Act. If the State has an outstanding obligation to adopt a control requirement, it remains obligated to do so, but may adopt it as a contingency measure. As discussed above, under EPA's Clean Data Policy,

certain obligations such as the requirement to submit ROP plans and attainment demonstrations may be suspended based on a determination that the area has attained the 8 hour NAAQS and will no longer apply if the area is redesignated to attainment. However, if an area experiences a violation of the 8 hour standard prior to being redesignated to attainment the requirements would once again apply.

We are adopting this option because, as noted in the June 2, 2003 proposal, the 8 hour standard is the standard that we have determined will protect public health and the environment. Only once an area demonstrates it has met and can maintain the health protective standard do we believe it STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 151 will be appropriate to shift these obligations to the contingency measures portion of the SIP. This scheme is consistent with what Congress intended. The CAA contemplates under subpart 2 that States must implement certain mandated requirements. Under the maintenance plan provision of the CAA( section 175A), such requirements may be shifted to the contingency measure portion of the SIP upon or after redesignation to attainment. Since the relevant NAAQS is now the 8 hour NAAQS, we believe it is appropriate to require these mandated controls to remain as part of the implemented SIP until an area attains the 8 hour NAAQS and is redesignated to attainment. On or after that date, a State may move such obligation to the contingency measures portion of the SIP consistent with sections 175A and 110( l).

Moreover, we believe it is appropriate to use attainment of the 8 hour NAAQS rather than attainment of the 1 hour NAAQS because, as provided elsewhere in this rulemaking, EPA will no longer be making determinations of whether an area has attained the 1 hour NAAQS and areas will not be required to demonstrate attainment or maintenance of the 1 hour NAAQS. Some areas may never attain the 1 hour NAAQS, as there will be no obligation to do so once it is revoked. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 152 The final rule covers the continued applicability of the NOx transport rules under section 51.905( f), rather than as an " applicable requirement" for purposes of section 110( l) because the NOx rules apply regardless of an area's attainment or nonattainment status for the 8 hour ( or the 1

hour) standard.

3. Comments and Responses:

Of the few commenters who addressed this issue in response to the June 2, 2003 proposal, several favored option 1, and several favored option 2. Of those who commented on the draft regulatory text, one commenter opposed the provision, and one comment was unclear as to the commenter's concerns. One other commenter supported the provision. Several commenters had clarifying questions.

RESPONSE: Our rationale for the choice of Option 2 is presented above. A more detailed discussion of other comments and responses appears in the response to comment document.

Section 51.905( c) Which portions of an area designated for the 8 hour NAAQS remain subject to the obligations identified in paragraph ( a) of this section? ( Section VI. C. 2 of proposal; see 68 FR 32820; 51.905( c) of draft regulatory text.) STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 153 1. Background.

In the June 2, 2003 notice, we proposed that the obligation to retain or to adopt and retain a mandatory control obligation applies only to the part of the 8 hour ozone nonattainment area that was designated nonattainment for the 1 hour ozone NAAQS. The proposal also provided an example of how this would work.

The draft regulatory text provided additional specificity concerning geographic applicability of the antibacksliding provisions. The draft text provided that with two exceptions only the portion of the designated area for the 8 hour NAAQS that was required to adopt the applicable requirements in 51.900( f) for purposes of the 1 hour NAAQS is subject to the obligations identified in paragraph ( a) of this section with several exceptions. The first exception is an area that is designated attainment for the 8 hour standard but that was nonattainment for the 1 hour standard with an unmet obligation to submit an attainment demonstration; for these areas, the draft regulatory text provided that the entire area designated nonattainment for the 8 hour ozone NAAQS would be subject to the 10 percent advance increment of reduction. The second exception is an area that is attainment for the 8 hour standard but that was STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 154 nonattainment under the 1 hour standard with an unmet obligation to submit an attainment demonstration; for these areas, the 110( l) maintenance plan would have to demonstrate maintenance for the entire 8 hour ozone attainment area.

2. Summary of Final Rule.

The final rule incorporates most aspects of the approach as that contained in the proposal and in the draft regulatory text. The final rule provides that only the portion of the designated area for the 8 hour NAAQS that was designated nonattainment for the 1 hour NAAQS is required to comply with the obligations in subparagraph 51.905( a),

except in one circumstance if the State elects to provide an early increment of progress or an early 8 hour attainment demonstration in lieu of an outstanding 1 hour attainment demonstration ( for an 8 hour nonattainment area/ 1 hour nonattainment area under 51.905( a)( 1)( ii)( B) and ( C)), the increment of progress or early 8 hour attainment plan must apply for purposes of the entire 8 hour nonattainment area.

The final rule does not follow the approach in the proposal for the maintenance plan requirement for 8 hour attainment areas. The maintenance plans required under section 51.905( a)( 3)( iii) and ( 4)( ii) must demonstrate maintenance only for the area designated nonattainment for STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 155 the 1 hour NAAQS at the time of designation of the 8 hour standard. We received comment that recommended this obligation apply only to the area that was originally designated nonattainment for the 1 hour standard. After considering this comment and our discussion in the preamble to the proposed rule, we agree with the commenter. In many States, attainment areas are identified county by county rather than identifying a group of counties as an attainment area. Thus, a State may have one or more groups of counties listed as a nonattainment area and then the remaining counties in the State are each identified individually as " attainment." See e. g., 40 CFR 81.311 ( Georgia); 81.329 ( Nevada). Because the area that has historically had a problem attaining the ozone standard is the area that was previously designated nonattainment for the 1 hour standard,

we believe it makes the most sense to require the maintenance plan for the area previously designated nonattainment for the 1 hour standard. By the time we revoke the 1 hour standard, we will set forth in 40 CFR Part 81, Subpart E, an identification of the boundaries of areas and the area designations and classifications for the 1 hour NAAQS at the time of the 8 hour designations.

3. Comments and Responses STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 156 a. Comments on June 2, 2003 Proposal:

With regard to limiting the applicability of 1 hour obligations to that portion of the 8 hour nonattainment area that was also part of the 1 hour nonattainment area, one commenter supports this policy, especially for the enhanced I/ M program. The commenter believes that the environmental benefit of requiring an extension of the enhanced I/ M program to areas recently added to the CMSA and designated nonattainment for the 8 hour NAAQS to be minimal, costly,

and disruptive of the continued implementation of the enhanced I/ M program in the current 1 hour nonattainment area.

One commenter objected to requiring the substitute planning requirement ( 10 percent advance increment of emission reductions) that applies to areas with an outstanding attainment demonstration for the entire 8 hour ozone nonattainment area. Instead, the commenter recommended it should only apply to the 1 hour nonattainment area.

RESPONSE: The final rule provides for retaining applicable emission control and growth requirements for an area's 1 hour classification in only the original 1 hour nonattainment area. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 157 As noted in the final rulemaking notice, we are now allowing the State to meet its unmet 1 hour attainment demonstration obligation through one of three alternative mechanisms, one of which is a 5 percent ( rather than a 10 percent) advance increment of emission reductions. The reduction is applied throughout the entire 8 hour nonattainment area because, although it is being submitted in lieu of the 1 hour requirement, it is intended to address the 8 hour nonattainment problem. Because this alternative to the 1 hour attainment demonstration is intended to address attainment and progress toward the 8 hour standard,

the advance increment of progress needs to be obtained from the 8 hour nonattainment area. We developed these alternatives in response to concerns that areas focus on the 8 hour standard rather than on the 1 hour standard and that continued planning obligations for the 1 hour standard would burden State resources. States still have the flexibility to choose to develop the 1 hour attainment demonstrations for the 1 hour area if they would like to restrict planning to the old area.

51.905( e) What obligations that applied for the 1 hour NAAQS will no longer apply after revocation of the 1 hour NAAQS for an area? ( Section VI. C. 3. d. of proposal; see 68 FR STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 158 32824.)

1. Background In the June 2, 2003 proposed rule ( 68 FR 328224), we proposed that once the 1 hour standard is revoked, EPA would no longer make findings of failure to attain that standard and, therefore, we would not reclassify areas based upon a finding that the area failed to attain the 1 hour NAAQS. We indicated areas should focus their resources on attainment of the 8 hour standard and stated that we believed it would be counterproductive to establish new obligations for States with respect to the 1 hour standard after they have begun planning for the 8 hour standard. In addition, we noted that the attainment dates for areas classified as marginal, moderate and serious had passed and that the CAA does not provide for reclassification of severe areas. We also noted other mechanisms that are available to make sure that States continue to make progress toward attaining the 8 hour NAAQS.

In addition, we indicated that conformity requirements would no longer apply under the 1 hour standard once the standard is revoked. The June 2, 2003 proposal explains that, under section 176( c) of the CAA, conformity applies to areas designated nonattainment or subject to the requirement to develop a maintenance plan pursuant to section 175A. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 159 Once the 1 hour standard is revoked, areas would no longer be designated nonattainment for the 1 hour standard or subject to the obligation to develop a maintenance plan under section 175A for the 1 hour standard and thus would no longer be subject to the obligation to demonstrate conformity ( either transportation conformity or general conformity) for that standard.

The draft regulatory text incorporated these concepts and also provided that, at the time of revocation of the 1

hour standard, any provisions of applicable SIPs that require conformity determinations in such areas for the 1 hour NAAQS will no longer be enforceable as a matter of law pursuant to section 176( c)( 5) of the Act.

Additionally, the draft regulatory text reflected the discussion in the preamble to the proposed rule regarding what portions of a 1 hour maintenance plan could be revised or removed once the 1 hour standard was revoked ( 68 FR 32823). The draft regulatory text provided that areas with approved 1 hour maintenance plans could modify those plans to remove the obligation to submit a maintenance plan for the 1 hour NAAQS eight years after approval of the initial 1 hour maintenance plan and to remove the obligation to implement contingency measures upon a violation of the 1 STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 160 hour NAAQS. The regulatory text provides, however, that these requirements would remain enforceable until EPA approved a SIP removing or revising them and also provided that EPA would not approve such revisions until EPA approves an 8 hour attainment demonstration for an area designated nonattainment for the 8 hour NAAQS or an 8 hour maintenance plan for an area designated attainment for the 8 hour NAAQS.

Finally, EPA noted that such a SIP revision must also be consistent with sections 110( l) and 193 of the Act.

2. Summary of Final Rule We are adopting the approach we set forth in our proposed rule and providing clarification regarding the penalty obligations under sections 181( b)( 4) and 185A of the CAA that apply in severe areas that do not attain the 1 hour standard by the applicable attainment date. The final rule provides that as of the effective date of revocation of the 1 hour standard:

Areas will not be obligated to continue to demonstrate conformity for the 1 hour NAAQS as of the effective date of the revocation of the 1 hour NAAQS.

We will no longer make findings of failure to attain the 1 hour standard and, therefore, ( a) we will not reclassify areas to a higher classification for the 1 STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 161 hour standard based on such a finding, and ( b) areas that were classified as severe for the 1 hour NAAQS are not obligated to impose fees as provided under sections 181( b)( 4) and 185A of the CAA.

An area with an approved 1 hour maintenance plan under section 175A of the CAA may modify the maintenance plan to remove obligations related to developing a second 10 year maintenance plan for the 1 hour NAAQS and the obligation to implement contingency measures upon a violation of the 1 hour NAAQS.

We continue to believe, as stated in the preamble to the proposed rule, that areas should focus their resources on attainment of the 8 hour standard and that it would be counterproductive to establish new obligations for States with respect to the 1 hour standard after they have begun planning for the 8 hour standard. Moreover, we do not believe there is a basis to determine whether an area has met the 1 hour standard once that standard no longer applies   once the 1 hour standard is revoked, there will not be an applicable attainment date with which to make a determination as to whether an area has met its attainment date or not. Since the obligations to reclassify areas and impose fees are based on a determination that an area has STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 162 failed to meet the standard by the appropriate attainment date, those obligations also would no longer apply for the 1 hour standard once the 1 hour standard has been revoked.

While we did not specifically state in our proposal that severe areas would no longer be obligated to impose fees under sections 181( b)( 4) and 185A based on a failure to attain the 1 hour NAAQS after the effective date of the revocation of the 1 hour NAAQS, it is a logical extension of our proposal as that obligation is triggered by a finding of failure to attain. In addition, this is consistent with Appendix B of the June 2, 2003 proposal, which did not identify the section 185A fee provision as an applicable requirement.

Regarding conformity, we are adopting the approach we set forth in our proposed rule.( 68 FR 32823). The final rule provides that, upon revocation of the 1 hour NAAQS for an area, conformity determinations will no longer be required for the 1 hour NAAQS. At that time, any provisions of applicable SIPs that require conformity determinations for the 1 hour standard in such areas will no longer be enforceable pursuant to section 176( c)( 5) of the CAA.

Under section 176( c) of the CAA, conformity applies to areas designated nonattainment or subject to the requirement STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 163 to develop a maintenance plan pursuant to section 175A for a specific NAAQS. Once the 1 hour standard is revoked, areas designated attainment for the 8 hour standard would no longer be subject to the obligation to demonstrate conformity for the 1 hour standard and would have no conformity obligation for the 8 hour standard. Likewise,

even areas designated nonattainment for the 8 hour standard would no longer have an obligation to demonstrate conformity under the 1 hour standard. The reason for this is that these areas would no longer be designated nonattainment for the 1 hour standard and would no longer be required to develop a maintenance plan under section 175A for purposes of the 1 hour standard.

Regarding the revisions to 1 hour maintenance plans, as noted above, upon revocation of the 1 hour NAAQS, an area with an approved 1 hour maintenance plan under section 175A of the CAA may modify the maintenance plan to remove both the obligation to submit a second maintenance plan for the 1 hour NAAQS 8 years after approval of the initial 1 hour maintenance plan and the obligation to implement contingency measures upon a violation of the 1 hour NAAQS. The maintenance plan requirements will remain enforceable as part of the approved 1 hour NAAQS SIP until such time as EPA STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 164 approves a SIP revision removing such obligations. We will not approve a SIP revision requesting these modifications until the State submits and EPA approves an attainment demonstration for the 8 hour NAAQS for an area designated nonattainment for the 8 hour ozone NAAQS or a maintenance SIP for the 8 hour NAAQS for an area designated attainment for the 8 hour NAAQS. Any revision to such SIP must meet the requirements of section 110( l) and 193 of the CAA.

3. Comments and Responses a. Comments on June 2, 2003 proposal:

Several commenters addressed this issue. Most agreed with the proposal, but recommended that we clarify that the section 185A penalty fees would not be imposed after the 1

hour standard is revoked. A few of the commenters disagreed on the basis that EPA should not revoke the 1 hour standard and that all requirements that apply for purposes of the 1

hour standard remain applicable.

Regarding conformity, the majority of commenters that addressed this issue objected to EPA's proposal. Most of these commenters believed the 1 hour standard and any 1 hour SIP budgets should remain in effect, such that for an area that was designated nonattainment under the 1 hour standard,

or was redesignated to attainment and had an approved STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 165 maintenance plan under the 1 hour standard, conformity requirements would still apply. Given the variety of comments we received about how conformity will be implemented, in this section we provide a response following each type of comment.

Comment: Several commenters indicated that revoking the 1 hour standard for conformity is backsliding,

and offered several arguments for why the 1 hour budgets should be retained in 1 hour nonattainment and maintenance areas.

Some commenters indicated that once approved, the motor vehicle emissions budget is part of the applicable implementation plan, and EPA may not render them nugatory for conformity purposes. Commenters also asserted that EPA may not unilaterally revise a state's SIP or suspend it, and in order to require states to revoke the budgets in their SIPs, EPA would have to find the budgets inadequate.

Further, commenters argued that EPA may not lawfully allow states to discontinue implementation of the budgets in their current SIPs, and if states were to decide on their own that budgets no longer apply for conformity purposes, commenters said that EPA would be obligated to impose sanctions pursuant to section 179( a)( 3). Commenters asserted that STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 166 states may not revise their SIPs to remove budgets without complying with section 110( l), which states that EPA cannot approve revisions " if the revision would interfere with any applicable requirement concerning attainment and reasonable further progress ( as defined in section 171), or any other applicable requirement of this Act."

Commenters also specifically made the point that revoking the 1 hour standard in areas that are maintenance for that standard conflicts with EPA's proposal that areas can modify discretionary measures only if section 110( l) is met.

Response: The CAA specifically states that conformity applies only in " a nonattainment area..." and " an area that was designated as a nonattainment area but that was later redesignated by the Administrator as an attainment area and that is required to develop a maintenance plan under section 7505a of this title..." ( 42 U. S. C. 7506( 5)). Therefore, CAA section 176( c)( 5) restricts conformity to nonattainment areas and areas that are required to submit maintenance plans under section 175A; in these areas, the Federal government's sovereign immunity is waived so that states can require conformity to be determined by the U. S. Department of Transportation. However, after revocation of the 1 hour STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 167 standard, the areas previously nonattainment for the 1 hour standard are no longer nonattainment for that standard.

Similarly, after revocation of the 1 hour standard, the areas previously required to submit 175A maintenance plans under the statute for the 1 hour standard will no longer be required to do so. Therefore, the statute will no longer waive sovereign immunity to allow states to require conformity determinations in such areas after revocation.

States are not taking any action to remove the budgets for the 1 hour ozone standard in their SIPs, nor are they required to do so. In fact, EPA has proposed that 8 hour nonattainment areas would be able to use the 1 hour budgets for conformity for the 8 hour standard, if they exist in an area ( November 5, 2003, proposed rule, 68 FR 62690). Thus,

although the 1 hour budgets would remain in the SIP, areas previously designated nonattainment or maintenance for the 1 hour standard would no longer be required or even authorized to show conformity under CAA section 176( c)( 5)

for that standard. Similarly, EPA would have no grounds for imposing sanctions where conformity is not conducted in these areas because there would be no SIP planning or implementation failure. EPA also disagrees that States cannot revise their SIPs to remove budgets without a STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 168 demonstration that 110( l) is met, because states will not be revising their SIPs to remove budgets.

As we acknowledged in our June 2, 2003, proposal, EPA's conclusion that conformity cannot apply in 1 hour maintenance areas once the 1 hour standard is revoked differs from the approach we planned to take in 1997. In 1997, we interpreted revoking the 1 hour ozone standard to mean that conformity would not apply for the 1 hour ozone standard in areas that were nonattainment for the 1 hour ozone standard, but that conformity would continue to apply for the 1 hour ozone standard in areas with a maintenance plan. However, the 1997 interpretation would lead to an unfair and counter intuitive result: areas that had attained the standard and had made the effort to establish a maintenance plan would have to continue a required program,

but areas that had not attained would not. We reconsidered this result and found it to be unfair and inappropriate.

Further, upon reanalyzing CAA section 176( c)( 5), we concluded that this interpretation did not fit with the text of the statute.

Although section 110( l) would normally require areas to demonstrate that removing prior SIP requirements would not interfere with any applicable requirements of the CAA, where STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 169 the CAA itself now forbids application of a prior requirement such a demonstration would be unnecessary.

Further, it would interfere with the statutory limitation on the applicability of conformity to require conformity determinations in areas that are no longer required by the CAA to submit 175A maintenance plans.

Comment: Commenters remarked that revoking the 1 hour ozone standard is of particular concern in areas that are currently nonattainment or maintenance for the 1 hour ozone standard that are projected to be attainment for the 8 hour ozone standard, because once the standard is revoked, these areas will no longer be subject to conformity. A couple of commenters made the point that revoking the 1 hour standard would have economic implications for their area because without transportation conformity, the emissions from the transportation sector could grow without restraint and therefore, emissions from the industrial sector would have to be limited further. Commenters were also concerned that their region would lose the ability to forecast whether a violation could occur.

Response: We promulgated the 8 hour ozone standard in response to the latest data and science regarding ozone; we believe the 8 hour ozone standard is more protective of STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 170 public health. In 1997, EPA made the decision to replace the 1 hour ozone standard with the 8 hour ozone standard,

because EPA concluded that the 1 hour standard is not needed to protect health and welfare.

It is our conclusion that areas that are in attainment for the 8 hour standard would not be subject to conformity because the statute explicitly limits the applicability of conformity to designated nonattainment and to maintenance areas. These areas still have an incentive to monitor the growth of emissions from the transportation sector; if these areas violate the 8 hour standard, EPA could designate them nonattainment for the 8 hour standard and conformity would then apply.

EPA notes that although States could not implement conformity, they could still require their MPOs to estimate regional emissions that would be generated by planned transportation activities to see whether a violation could occur, and could even limit the MPOs from growing beyond a certain amount.

b. Comments on draft regulatory text ( sect. 51.905( e)

of the draft):

Comment: Several commenters supported this provision.

One commenter supports, in part, our proposal to allow STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 171 amendment of maintenance plans, but takes issue with the fact that States would face a continuing obligation to implement contingency measures after revocation of the 1

hour standard and the criteria for approval of such amendments. After the 1 hour NAAQS is revoked, a State's obligation to implement contingency measures should automatically be lifted. The Illinois EPA recommends that amendments to the maintenance plans for these areas be approved after the 1 hour NAAQS has been revoked.

RESPONSE: Once we revoke the 1 hour standard, the requirement for submission   or subsequent improvements to or additions   of a section 175A maintenance plan under the 1 hour standard are no longer required. The State still has an obligation to ensure that air quality remains clean, and to invoke contingency measures if concentration increases threaten to violate the NAAQS. The final rule provides that, upon revocation of the 1 hour NAAQS, an area with an approved 1 hour maintenance plan under section 175A of the CAA may modify the maintenance plan to remove the obligation to submit a maintenance plan for the 1 hour NAAQS 8 years after approval of the initial 1 hour maintenance plan and to remove the obligation to implement contingency measures upon a violation of the 1 hour NAAQS. The final rule provides STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 172 that EPA would not approve a SIP revision requesting these modifications until the State submits and EPA approves an attainment demonstration for the 8 hour NAAQS for an area initially designated nonattainment for the 8 hour ozone NAAQS or a maintenance SIP for the 8 hour NAAQS for an area initially designated attainment for the 8 hour NAAQS. Any revision to such SIP must meet the requirements of section 110( l) and 193 of the CAA. For areas that are not required to submit attainment demonstrations ( e. g., marginal areas),

the SIP revisions that affect prior maintenance plans under the 1 hour standard may be made when other portions of the 8 hour SIP are due ( e. g, the NSR provisions).

Comment: Several commenters support the predication that upon revocation of the 1 hour standard, EPA would no longer be required to determine whether an area has attained the 1

hour standard by its 1 hour attainment deadline or to reclassify the area to a higher classification based on a " failure to attain" determination. One commenter agrees with EPA's approach to allow States to request the removal of obligations to submit an 8 year update to 1 hour maintenance plans and implement contingency measures upon a violation of the standard. Another commenter recommended that, in general, the rule should make it clear that any STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 173 revocation actions must comply with Sections 1l0( 1) and 193.

RESPONSE: The proposed rule   as well as the final rule   provides that EPA will not approve revisions to the maintenance plan until EPA approves the area's 8 hour SIP for either attainment or maintenance, which will ensure noninterference with the 8 hour standard. However, the final rule also includes a requirement that the changes must be in accordance with sections 110( l) and 193.

Comment: One commenter believes that proposed 40 CFR § 51.905( e)( l) contains an apparent misstatement that EPA should correct. That provision states that upon revocation of the 1 hour NAAQS, an area with an approved maintenance plan for that NAAQS may modify that plan to remove the obligation under CAA § 175A( b) to submit a " second round"

maintenance plan eight years after redesignation to attainment and to remove the obligation to implement contingency measures upon a 1 hour NAAQS violation. The provision goes on to say that EPA will not approve a SIP revision making these modifications until the state submits and EPA approves: ( 1) an 8 hour attainment demonstration, if the area is designated nonattainment for the 8 hour NAAQS;

or ( 2) an 8 hour maintenance SIP under proposed 40 CFR § 51.905( a)( 3)( iii), if the area is designated attainment for STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 174 the 8 hour standard. Option ( 2) does not make sense,

however. Proposed 40 CFR § 51.905( e) by its terms applies to areas with approved 1 hour maintenance plans. Thus, these areas by definition have been redesignated to attainment   i. e., are no longer nonattainment   for the 1 hour NAAQS.

Yet proposed 40 CFR § 51.905( a)( 3)( iii) applies only to areas that are " designated nonattainment for the 1 hour NAAQS at the time of revocation of the 1 hour NAAQS". Thus,

contrary to the last clause of § 51.905( e)( l), areas that are maintenance for the 1 hour NAAQS and attainment for the 8 hour NAAQS cannot be subject to § 51.905( a)( 3)( iii).

RESPONSE: The commenter has pointed out a flaw in the proposal. The final rule has been modified from the proposal to account for this situation. A separate parallel provision has been established in section 51.905( a)( 4) for areas that have 1 hour maintenance plans at the time of revocation of the 1 hour standard under which they would be obligated to submit a maintenance plan under section 110( a)( 1). Section 51.905( e)( 1) has been modified to provide that the State would not be able to modify the existing 1 hour maintenance plan until EPA approves the new 8 hour maintenance plan.

Comment: One commenter provided suggested language changes STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 32When EPA promulgated the NOx SIP Call, we required the same level of reductions for both the 1 hour and 8 hour ozone NAAQS ( 63 FR 57356, October 27, 1998). In response to the Court of Appeals remand of the 8 hour standard, EPA 175 to section 51.905( e). that would have basically retained the section 175A maintenance plan and the conformity requirement.

RESPONSE: As noted above under other similar comments on the June 2, 2003 proposal, once EPA revokes the 1 hour standard, and the area is an 8 hour attainment area, section 175A maintenance provisions do not apply and conformity for the 1 hour standard no longer applies.

Section 51.905( f) What is the continued applicability of the NOx SIP Call after revocation of the 1 hour NAAQS? ( Section VI. C. 3. c. of proposal; see 68 FR 32824)

1. Background In the June 2, 2003 proposal ( 68 FR 32824),

we noted that it is important to ensure that the transition to the 8 hour standard does not jeopardize the controls required to be in place under the NOx SIP Call rule and the section 126 rule ( i. e., the rules for addressing the longrange transport of ozone and its precursor, NOx). We jointly referred to these rules in the proposal as the NOx transport rules. We indicated that we plan to lift the stay of the 8 hour basis for the NOx transport rules. 32 STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 stayed the 8 hour basis of the NOx SIP Call ( 65 FR 2674, January 18, 2000). However, since the same level of reductions was required for both the 8 hour and 1 hour standards, the stay had no practical effect on States' compliance with the rule. Because EPA also stayed the 8 hour portion of the Section 126 Rule, we did not move forward to make the section 126 findings under the 8 hour standard which would trigger the 8 hour control requirements ( 65 FR 2674, January 18, 2000). We plan to complete rulemaking action on the 8 hour petitions at the time we lift the 8 hour stay. All of the States affected by the 1 hour and/ or 8 hour Section 126 Rule are also covered by the NOx SIP Call. The Section 126 Rule contains a provision under which the Section 126 findings and control requirements would be withdrawn if States have approved SIPs meeting the NOx SIP Call. The EPA has already withdrawn the 1 hour Section 126 Rule in 3 States and the District of Columbia and proposed to withdraw the 1 hour rule in all other affected States except one. ( We expect to propose action with respect to the rule in the remaining State shortly.)

176 Regardless of whether we lift that stay, the controls required have substantial benefits for reductions of both 1 hour and 8 hour ozone levels. We indicated that we believe that relaxing such controls would be contrary to the principles we identified in the proposal for an effective transition. Thus, we proposed that States must continue to adhere to the emission budgets established by the NOX transport rules after the 1 hour standard is revoked in whole or in part.

The draft regulatory text reflected the discussion in the June proposal. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 177 2. Summary of Final Rule We are adopting the approach we set forth in our proposed rule and draft regulatory text.

States must continue to adhere to the emission budgets established by the NOx transport rules after the 1 hour standard is revoked. States retain the authority to revise control obligations they have established for specific sources or source categories under the NOx SIP Call rule so long as the State demonstrates consistent with section 110( l) that such modification will not interfere with attainment of or progress toward meeting the 8 hour NAAQS or any other applicable requirement of the CAA. We continue to believe that the reductions required by the NOx transport rules are necessary to address transported emissions for the 8 hour ozone NAAQS as well as the 1 hour ozone NAAQS.

3. Comments and Responses ( i) Comments on the June 2, 2003 proposal:

Only a handful of commenters addressed this issue, all of whom supported the proposal. Several of these commenters recommended that we lift the stay of the NOx transport rules with respect to the 8 hour standard. Additionally, only a few commenters specifically commented on this provision of the draft regulatory text ( 51.905( f)), and all supported the concept. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 178 D. What is the Required Timeframe for Obtaining Emissions Reductions to Ensure Attainment by the Attainment Date?

( Section VI. E of the proposed rule ( 68 FR 32826); Section 51.908( e) of the draft regulatory text; Section 51.908 of the final rule.

1. Background: In the June 2003 proposal, we proposed that emissions reductions needed for attainment must be implemented by an area's attainment date. We noted this meant that emissions reductions must be implemented by the beginning of the final ozone season prior to the attainment date. For example, for areas with an attainment date in May 2010, the emissions reductions need to be implemented by the beginning of the 2009 ozone season because a determination of attainment will be based on air quality monitoring data from 2007, 2008 and 2009. The proposal cautioned that States should be aware of the consequences of failing to implement the control measures necessary for attainment sufficiently far in advance of their attainment date. As noted above,

for areas covered under subpart 2, section 181( a)( 5) of the CAA allows up to two 1 year attainment date extensions if two criteria are met: the area has complied with all requirements and commitments in the approved SIP and the area has no more than one exceedance of the NAAQS in the STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 33 See section 4. entitled, " How Will EPA Address the Provision Regarding 1 Year Extensions?" where we interpret the clause " no more than 1 exceedance" in section 181( 5)( b) to mean, for purposes of the 8 hour NAAQS, that the 4th high reading at an ozone monitor in the ozone season preceding the attainment date is less than 0.85 ppm.

179 attainment year. As provided above, we've interpreted the second criterion to mean that to obtain the first 1 year extension, the area must be meeting the level of the standard in the attainment year itself. 33 Thus, States should ensure that the emissions reductions are implemented to ensure that ozone levels for the ozone season preceding the attainment date are below the level of the standard. If an area does not meet the eligibility requirements for the 1 year extension, it would be subject to a reclassification to a higher classification ( bump up). Areas covered under subpart 1 are able to obtain up to two 1 year attainment date extensions, however there is no provision for a bump up in subpart 1. If an area covered under subpart 1 fails to attain, section 179 of the CAA provides that EPA publish a finding of failure to attain which starts a 1 year time frame for States to submit a SIP revision that provides for attainment within a specified time frame.

2. Summary of final rule: In section 51.908, we are adopting the approach we set forth in our proposed rule, STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 180 namely that emissions reductions needed for attainment must be implemented by the beginning of the ozone season immediately preceding the area's attainment date. We believe that Congress contemplated that control measures would continue to be implemented up to the attainment year.

For example, section 182( c)( 2)( B) requires areas classified as serious or higher to achieve an average of 3 percent reduction in emissions per year over each three year period until the area's attainment date. If Congress intended areas to achieve all reductions needed for attainment three years prior to attainment, then the last 9 percent reductions required for serious and above areas would be reductions beyond those needed for attainment. We do not believe that Congress mandated these reductions in addition to the reductions needed to attain the standard. In fact,

this requirement is included in the statute as a part of the subparagraph addressing attainment and reasonable further progress, which indicates that Congress intended it to address progress toward attainment. This is further supported by the definition of reasonable further progress in section 171( 1) as " annual incremental reductions in emissions ... for the purpose of ensuring attainment ..."

Other provisions in the CAA also support the concept STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 34 As discussed in the section regarding the two 1 year attainment date extensions, section 172( a)( 2)( C), which applies to all pollutants, allows for a 1 year attainment date extension if the area has had " minimal exceedances" in the attainment year and section 181( a)( 5), which applies to ozone nonattainment areas classified under subpart 2, allows for a 1 year extension if the area has had no more than 1 exceedance in the attainment year.

181 that areas do not need to achieve three years in advance of the attainment date the full complement of reductions needed for attainment. For example, Congress only provided marginal areas with three years to attain the standard and did require at least minimal additional controls be implemented in such areas. In addition, the fact that Congress provided for two 1 year extensions of the attainment date also indicated that Congress believed that some areas might not be fully implementing all measures needed for attainment three years in advance of the attainment date. Rather, Congress contemplated that areas would have air quality healthy enough to make it substantially likely the area would attain within the next one or two years. 34 Finally, we note that the standard itself does not contemplate that air quality must be at " attainment levels" for each of the three years on which attainment is based. Rather, attainment is determined based on an average of the 4th high reading at a monitor over a STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 182 three year period. Thus, the 4th high reading for an area could be above the standard for one or both of the years preceding the attainment year, but so long as the 4th high level for the other year( s) was low enough to produce an average at or below 0.084 ppm, the area would be attaining the standard.

As noted in the June 2003 preamble, despite the fact that we believe an area need not have all controls implemented until the beginning of the final attainment season, the State needs to consider that attainment is based on a 3 year average. Thus, the State will need to ensure that implementation of controls is not unduly delayed. A State that plans to achieve reductions by the beginning of the ozone season prior to the attainment date may still experience meteorology conducive to very high ozone formation in that last ozone season that may result in the area having a 4th highest daily ozone concentration above the level of the 8 hour standard, making it ineligible for the first of the 1 year extensions. Such an area   if classified under subpart 2   would then be reclassified ( bumped up) to a higher classification and be subject to additional planning requirements and mandatory control measures. Thus, a State should be aware of the consequences STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 35Memorandum, `` Guidance on the Reasonably Available Control Measures ( RACM) Requirement and Attainment Demonstration Submissions for Ozone Nonattainment Areas.'' John S. Seitz, Director, Office of Air Quality Planning and Standards. November 30, 1999. Web site: http:// www. epa. gov/ ttn/ oarpg/ t1pgm. html.

183 of delaying too long to implement control measures needed for attainment. Additionally, in reviewing implementation timeframes in SIPs, EPA will consider whether those timeframes are as expeditious as practicable. A guidance memorandum from John Seitz of November 30, 199935 reiterates the need to implement measures as expeditiously as practicable:

In order for EPA to determine whether an area has provided for implementation as expeditiously as practicable, the State must explain why the selected implementation schedule is the earliest schedule based on the specific circumstances of that area. Such claims cannot be general claims that more time is needed but rather should be specifically grounded in evidence of economic or technologic infeasibility. While it may be appropriate for some control measures to be implemented shortly after adoption, the EPA recognizes that other measures may need a longer period. The EPA will review the State's submission to ensure that sufficient information is provided for the EPA to determine whether the State has adopted all RACM necessary for attainment as expeditiously as practicable and provided for implementation of those measures as expeditiously as practicable. The EPA will make those determinations based on the information provided by the State and any other information available to the EPA at the time the Agency approves or disapproves the attainment demonstration. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 184 3. Comments and Responses Comment: Some commenters agreed with our proposal as written, i. e., to require that emission reductions needed for attainment be implemented by the beginning of the ozone season prior to the attainment year.

However, several commenters disagreed with the timeframe that was included in our proposal that required reductions be in place by the beginning of the ozone season prior to the attainment date because it precludes areas from realizing the benefit of Federal measures prior to developing additional local controls.

Another commenter stated that the attainment deadlines place an extraordinary burden on metropolitan areas to achieve the level of emissions reductions necessary to demonstrate attainment. The commenter felt that requiring emissions reductions to be implemented at the beginning of the ozone season prior to the attainment date is one year earlier than is required. The commenter stated that so long as there are no exceedances in the attainment year, i. e.,

having controls in place by the beginning of the ozone season of the attainment year, the area has meet the statutory requirement and could qualify for the first of two 1 year attainment date extensions allowed under the CAA. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 185 The commenter further stated that controls for moderate areas would need to be in place by about the same time the area's SIP must be submitted to EPA in order to provide three years of clean data for the demonstration of attainment.

Other commenters stated that all emissions reductions needed for attainment must be implemented in sufficient time to ensure attainment by the attainment date without relying on the CAA provisions for the 1 year extensions.

Response: Section 172( c)( 2) of the CAA requires that emissions reductions needed for attainment be phased in such that RFP toward attainment is achieved. For areas classified as moderate under subpart 2, their attainment date would be as expeditiously as practicable but no later than 6 years after the date of classification. Their ROP requirement would be at least a 15 percent VOC emissions reduction from the base year to be achieved no later than 6 years after the base year. However, if the area needed more than 15 percent VOC reductions in order to demonstrate attainment, then any additional reductions would also have to be achieved by the beginning of the ozone season prior to the area's attainment date.

States should be aware of the consequences of failing STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 186 to implement the control measures necessary for attainment sufficiently far in advance of the attainment date. For areas covered under subpart 2, section 181( a)( 5) of the CAA does allow for up to two 1 year attainment date extensions in certain circumstances. The final rule on how those extension provisions would be implemented appears elsewhere in this preamble under the discussion of attainment dates.

To obtain the first of the 1 year extensions, the CAA basically requires that the area be meeting the level of the standard in the attainment year itself, even if the area has not actually attained considering the most recent 3 years of data. Thus, the States should ensure that the emissions reductions be implemented to ensure that ozone levels for the ozone season preceding the attainment date are below the level of the standard. If an area does not meet the eligibility requirements for a 1 year extension ( as proposed elsewhere in this rulemaking) in the attainment year, then the area would not be eligible for an attainment date extension, and EPA would have an obligation to reclassify the area to a higher classification (" bump up"). A marginal area with an attainment date 3 years after its nonattainment designation that fails to attain would be subject to bump up to at least moderate, and would then have to prepare a plan STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 187 to attain within 3 years afterward ( 6 years after their nonattainment designation).

There is further discussion of this situation as it relates to the 1 hour ozone standard in the General Preamble of April 16, 1992 ( 57 FR 13498, 13506); this discussion may have some applicability to the 8 hour standard.

Areas covered under subpart 1 are also able to obtain up to two 1 year extensions of the attainment date ( see section 172( a)( 2)( C)). There is no provision for bump up in classification similar to that under subpart 2. However, if an area fails to attain, section 179 of the CAA provides that EPA publish a finding that the area failed to attain.

The State then must submit within 1 year after that publication a revision to the SIP that provides for attainment within the time provided under section 179.

Section 179 also provides that the SIP revision must also include any additional measures that EPA may prescribe.

Comment: Several commenters suggested that nonattainment areas should be afforded the opportunity to install controls in time to monitor for attainment before the attainment deadline. The commenters believes that for many industrialized and metropolitan areas classified under Subpart 2 as marginal, moderate or serious, it will not be STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 188 feasible to have stationary and mobile source controls in place three years before the attainment deadlines for the purposes of attainment monitoring. Pragmatically, state SIPS will not be finalized until mid 2007, at which time industrial facilities can begin the 18 24 month period for detailed engineering, permitting and procurement of NOX control equipment. The installation of controls would occur over a 5 year average facility turnaround period.

Furthermore, Tier II fuels and engines will just be entering the market as will cleaner diesel fuel and engines. It is virtually certain that many of these areas will not have the necessary emission reductions in place three years before the attainment deadline and will be required to rely on the case by case extensions to the designated attainment deadlines. The commenters believe that Congress did not intend for EPA to establish attainment deadlines that would in a large number of castes automatically require areas to use deadline extensions; such areas have probably been misclassified. All nonattainment areas should be afforded the opportunity to install controls in time to monitor for attainment by the attainment deadline, but not three years prior to the attainment year. This would also eliminate the need for case by case extensions. STAFF DRAFT   DO NOT QUOTE, CITE OR DISTRIBUTE   2/ 26/ 04 189 RESPONSE: The final rule does not require emission reductions to be in place three ozone seasons prior to the attainment date. However, the after the fact determination of whether an area actually attains the NAAQS by its attainment date must be done by looking back at the previous 3 years of ambient air quality data. However, as noted elsewhere in this preamble, the Act provides for up to two 1 year extensions of the attainment date.

Comment: Marginal areas may not be able to demonstrate compliance in three years and the final rule should provide for automatic extensions for such areas. Additional time to implement all of these reductions may be required in order for marginal areas to comply. By creating an automatic extension, EPA will avoid the inevitable cost of SIP nonattainment planning problems that communities will face these measures are fully implemented.