(a) Revisions to the State Implementation Plan submitted by the Massachusetts Department of Environmental Protection on April 1, 1999, and supplemented on June 25, 1999 and September 9, 1999. The revisions are for the purpose of satisfying the rate of progress requirements of sections 182(b)(1) and 182(c)(2)(B) of the Clean Air Act for the Springfield, Massachusetts serious ozone nonattainment area.

(b) Approval - Revisions to the State Implementation Plan submitted by the Massachusetts Department of Environmental Protection on July 27, 1998, October 1, 1998 and August 13, 1999. The revisions are for the purpose of satisfying the attainment demonstration requirements of section 182(c)(2)(A) of the Clean Air Act, for the Springfield (Western Massachusetts) serious ozone nonattainment area. The revision establishes an attainment date of December 31, 2003 for the Springfield, Massachusetts serious ozone nonattainment area. This revision establishes motor vehicle emissions budgets for 2003 of 23.77 tons per day of volatile organic compounds (VOC) and 49.11 tons per day of nitrogen oxides (NO_X) to be used in transportation conformity in the Springfield, Massachusetts serious ozone nonattainment area.

(c) Revisions to the State Implementation Plan submitted by the Massachusetts Department of Environmental Protection on April 10, 2002 and amended on July 26, 2002. The revisions are for the purpose of satisfying the rate of progress requirements of sections 182(b)(1) and 182(c)(2)(B) of the Clean Air Act for the Massachusetts portion of the Boston-Lawrence-Worcester serious ozone nonattainment area.

(d) Approval - Revisions to the State Implementation Plan submitted by the Massachusetts Department of Environmental protection on July 27, 1998, and September 6, 2002. The revisions are for the purpose of satisfying the one-hour ozone attainment demonstration requirements of section 182(c)92)(A) pof the Clean Air Act, for the Boston-Lawrence-Worcester, MA-NH serious ozone nonattiainment area. The revision establishes a one-hour attainment date of November 15, 2007l, for the Boston-Lawrence-Worcester, MA-NH serious ozone nonattainment area. This revision establishes motor vehicle emissions budgets for 2007 of 86.7 tons per day of volatile organic compounds and 226.363 tons per day of nitrogen oxides to be used in transportation conformity in the Massachusets portion of the Boston-Lawrence-Worcester, MA-NH serious ozone nonattainment area.

(e) Determination of Attainment for the One-Hour Ozone Standard. Effective May 30, 2012, EPA is determining that the Springfield (Western Massachusetts) one-hour ozone nonattainment area did not meet its applicable one-hour ozone attainment date of December 31, 2003, based on 2001-2003 complete, quality-assured ozone monitoring data. Separate from and independent of this determination, EPA is determining that the Springfield (Western Massachusetts) one-hour ozone nonattainment area met the one-hour ozone standard, based on 2007-2009 complete, quality-assured ozone monitoring data at all monitoring sites in the area. EPA's review of the ozone data shows that the area began attaining the one-hour ozone standard during the 2007-2009 monitoring period, and has continued attaining the one-hour standard through the 2008-2010 and 2009-2011 monitoring periods.

(f) Determination of Attainment for the One-Hour Ozone Standard. Effective June 28, 2012, EPA is determining that the Boston-Lawrence-Worcester, MA-NH one-hour ozone nonattainment area met the one-hour ozone standard, by the area's applicable attainment date of November 15, 2007, based on 2005-2007 complete, certified, quality-assured ozone monitoring data at all monitoring sites in the area.

(g) Determination of Attainment.

(h) Determinations of Attainment: Effective July 19, 2012.

(i) Revisions to the State Implementation Plan submitted by the Massachusetts Department of Environmental Protection on January 31, 2008. These revisions are for the purpose of satisfying the rate of progress requirement of section 182(b)(1) from 2002 through 2008, and the contingency measure requirement of sections 172(c)(9) and of the Clean Air Act, for the Boston-Lawrence-Worcester (E. MA) moderate 8-hour ozone nonattainment area, and the Springfield (W. MA) moderate 8-hour ozone nonattainment area. These revisions establish motor vehicle emission budgets for 2008 of 68.30 tons per day of volatile organic compounds (VOCs) and 191.30 tons per day of nitrogen oxides (NO_X) to be used in transportation conformity in the Boston-Lawrence-Worcester (E. MA) moderate 8-hour ozone nonattainment area. These revisions also establish motor vehicle emission budgets for 2008 for the Springfield (W. MA) moderate 8-hour ozone nonattainment area of 11.80 tons per day for VOCs, and 31.30 tons per day for NO_X.

(j) Approval - Reasonably Available Control Technology Demonstration for the 1997 8-hour ozone standard submitted by the Massachusetts Department of Environmental Protection on January 31, 2008. The revision consists of the state's certification that with regard to the 1997 8-hour ozone standard, Reasonably Available Control Technology controls have been implemented for all sources in the state covered by EPA's Control Techniques Guidelines (CTG) and for all major sources of volatile organic compound and nitrogen oxide emissions. The submittal also includes negative declaration for several CTG categories.

(k) Determination of attainment for the eight-hour ozone standard. Effective June 3, 2016, the EPA is determining that complete quality-assured and certified ozone monitoring data for 2012 to 2014 show the Dukes County, Massachusetts eight-hour ozone nonattainment area attained the 2008 eight-hour ozone standard by its July 20, 2015 attainment deadline. Therefore, the EPA has met the requirement pursuant to CAA section 181(b)(2)(A) to determine, based on the area's air quality data as of the attainment date, whether the area attained the standard. The EPA also determined that the Dukes County nonattainment area will not be reclassified for failure to attain by its applicable attainment date under section 181(b)(2)(A).

(l) On February 9, 2018, Massachusetts submitted a certification that its air emissions reporting requirements applicable to stationary sources meet the emission statement requirements of section 182(a)(3)(B) of the Clean Air Act. The certification was submitted as a SIP revision in partial fulfillment of obligations for nonattainment areas under EPA's 2008 8-hour ozone standard.