Section 51.1105 - Transition from the 1997 ozone NAAQS to the 2008 ozone NAAQS and anti-backsliding(a)Requirements that continue to apply after revocation of the 1997 ozone NAAQS -(1)2008 ozone NAAQS nonattainment and 1997 ozone NAAQS nonattainment. The following requirements apply to an area designated nonattainment for the 2008 ozone NAAQS and also designated nonattainment for the 1997 ozone NAAQS, or nonattainment for both the 1997 and 1-hour ozone NAAQS, at the time of revocation of the respective ozone NAAQS: The area remains subject to the obligation to adopt and implement the applicable requirements of § 51.1100(o) , for any ozone NAAQS for which it was designated nonattainment at the time of revocation, in accordance with its classification for that NAAQS at the time of that revocation, except as provided in paragraph (b) of this section.(2)2008 ozone NAAQS nonattainment and 1997 ozone NAAQS maintenance. For an area designated nonattainment for the 2008 ozone NAAQS that was redesignated to attainment for the 1997 ozone NAAQS prior to April 6, 2015 (hereinafter a "maintenance area") the SIP, including the maintenance plan, is considered to satisfy the applicable requirements of 40 CFR 51.1100(o) for the revoked NAAQS. The measures in the SIP and maintenance plan shall continue to be implemented in accordance with the terms in the SIP. Any measures associated with applicable requirements that were shifted to contingency measures prior to April 6, 2015 may remain in that form. After April 6, 2015, and to the extent consistent with any SIP for the 2008 ozone NAAQS and with CAA sections 110(l) and 193, the state may request that obligations under the applicable requirements of § 51.1100(o) be shifted to the SIP's list of maintenance plan contingency measures for the area.(3)2008 ozone NAAQS attainment and 1997 ozone NAAQS nonattainment. For an area designated attainment for the 2008 ozone NAAQS, and designated nonattainment for the 1997 ozone NAAQS as of April 6, 2015 or for both the 1997 and the 1-hour ozone NAAQS as of the respective dates of their revocations, the area is no longer subject to nonattainment NSR and the state may at any time request that the nonattainment NSR provisions applicable to the area be removed from the SIP. The state may request, consistent with CAA sections 110(l) and 193, that SIP measures adopted to satisfy other applicable requirements of § 51.1100(o) be shifted to the SIP's list of maintenance plan contingency measures for the area. The area's approved PSD SIP shall be considered to satisfy the state's obligations with respect to the area's maintenance of the 2008 ozone NAAQS pursuant to CAA section 110(a)(1).(4)2008 ozone NAAQS attainment and 1997 ozone NAAQS maintenance. An area designated attainment for the 2008 ozone NAAQS with an approved CAA section 175A maintenance plan for the 1997 ozone NAAQS is considered to satisfy the applicable requirements of 40 CFR 51.1100(o) through implementation of the SIP and maintenance plan provisions for the area. After April 6, 2015, and to the extent consistent with CAA sections 110(l) and 193, the state may request that obligations under the applicable requirements of 40 CFR 51.1100(o) be shifted to the list of maintenance plan contingency measures for the area. For an area that is initially designated attainment for the 2008 ozone NAAQS and which has been redesignated to attainment for the 1997 ozone NAAQS with an approved CAA section 175A maintenance plan and an approved PSD SIP, the area's approved maintenance plan and the state's approved PSD SIP for the area are considered to satisfy the state's obligations with respect to the area's maintenance of the 2008 ozone NAAQS pursuant to CAA section 110(a)(1).(b)Effect of Redesignation or Redesignation Substitute.(1) An area remains subject to the anti-backsliding obligations for a revoked NAAQS under paragraphs (a)(1) and (2) of this section until either EPA approves a redesignation to attainment for the area for the 2008 ozone NAAQS; or EPA approves a demonstration for the area in a redesignation substitute procedure for a revoked NAAQS. Under this redesignation substitute procedure for a revoked NAAQS, and for this limited anti-backsliding purpose, the demonstration must show that the area has attained that revoked NAAQS due to permanent and enforceable emission reductions and that the area will maintain that revoked NAAQS for 10 years from the date of EPA's approval of this showing.(2) If EPA, after notice-and-comment rulemaking, approves a redesignation to attainment, the state may request that provisions for nonattainment NSR be removed from the SIP, and that other anti-backsliding obligations be shifted to contingency measures provided that such action is consistent with CAA sections 110(l) and 193. If EPA, after notice and comment rulemaking, approves a redesignation substitute for a revoked NAAQS, the state may request that provisions for nonattainment NSR for that revoked NAAQS be removed, and that other anti-backsliding obligations for that revoked NAAQS be shifted to contingency measures provided that such action is consistent with CAA sections 110(l) and 193.(c)Portions of an area designated nonattainment or attainment for the 2008 ozone NAAQS that remain subject to the obligations identified in paragraph (a) of this section. Only that portion of the designated nonattainment or attainment area for the 2008 ozone NAAQS that was required to adopt the applicable requirements in § 51.1100(o) for purposes of the 1-hour or 1997 ozone NAAQS is subject to the obligations identified in paragraph (a) of this section. Subpart C of 40 CFR part 81 identifies the areas designated nonattainment and associated area boundaries for the 1997 ozone NAAQS at the time of revocation. Areas that are designated nonattainment for the 1997 ozone NAAQS at the time of designation for the 2008 ozone NAAQS may be redesignated to attainment prior to the effective date of revocation of that ozone NAAQS.(d)Obligations under the 1997 ozone NAAQS that no longer apply after revocation of the 1997 ozone NAAQS - (1)Second 10-year Maintenance plans. As of April 6, 2015, an area with an approved 1997 ozone NAAQS maintenance plan under CAA section 175A is not required to submit a second 10-year maintenance plan for the 1997 ozone NAAQS 8 years after approval of the initial 1997 ozone NAAQS maintenance plan.(2)Determinations of failure to attain the 1997 and/or 1-hour NAAQS.(i) As of April 6, 2015, the EPA is no longer obligated to determine pursuant to CAA section 181(b)(2) or section 179(c) whether an area attained the 1997 ozone NAAQS by that area's attainment date for the 1997 ozone NAAQS.(ii) As of April 6, 2015, the EPA is no longer obligated to reclassify an area to a higher classification for the 1997 ozone NAAQS based upon a determination that the area failed to attain the 1997 ozone NAAQS by the area's attainment date for the 1997 ozone NAAQS.(iii) For the revoked 1-hour and 1997 ozone NAAQS, the EPA is required to determine whether an area attained the 1-hour or 1997 ozone NAAQS by the area's attainment date solely for anti-backsliding purposes to address an applicable requirement for nonattainment contingency measures and CAA section 185 fee programs. In making such a determination, the EPA may consider and apply the provisions of CAA section 181(a)(5) and former 40 CFR 51.907 in interpreting whether a 1-year extension of the attainment date is applicable under CAA section 172(a)(2)(C).(e)Continued applicability of the FIP and SIP requirements pertaining to interstate transport under CAA section 110(a)(2)(D)(i) and (ii) after revocation of the 1997 ozone NAAQS. All control requirements associated with a FIP or approved SIP in effect for an area as of April 6, 2015, such as the NOX SIP Call, the CAIR, or the CSAPR shall continue to apply after revocation of the 1997 ozone NAAQS. Control requirements approved into the SIP pursuant to obligations arising from CAA section 110(a)(2)(D)(i) and (ii), including 40 CFR 51.121 , 51.122 , 51.123 and 51.124 , may be modified by the state only if the requirements of §§ 51.121 , 51.122 , 51.123 and 51.124 , including statewide NOX emission budgets continue to be in effect. Any such modification must meet the requirements of CAA section 110(l).(f)New source review. An area designated nonattainment for the 2008 ozone NAAQS and designated nonattainment for the 1997 ozone NAAQS on April 6, 2015 remains subject to the obligation to adopt and implement the major source threshold and offset requirements for nonattainment NSR that apply or applied to the area pursuant to CAA sections 172(c)(5), 173 and 182 based on the highest of: (i) The area's classification under CAA section 181(a)(1) for the 1-hour NAAQS as of the effective date of revocation of the 1-hour ozone NAAQS; (ii) the area's classification under 40 CFR 51.903 for the 1997 ozone NAAQS as of the date a permit is issued or as of April 6, 2015, whichever is earlier; and (iii) the area's classification under § 51.1103 for the 2008 ozone NAAQS. Upon removal of nonattainment NSR obligations for a revoked NAAQS under § 51.1105(b) , the state remains subject to the obligation to adopt and implement the major source threshold and offset requirements for nonattainment NSR that apply or applied to the area for the remaining applicable NAAQS consistent with this paragraph.80 FR 12314, Mar. 6, 2015