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Air Quality Conformity Status

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Since most all of Massachusetts (with limited exceptions) was designated on 5/21/12 by the United States Environmental Protection Agency as “unclassifiable/attainment” for the latest ozone standard, a conformity determination for the 2014-17 Massachusetts State Transportation Improvement Program is not required. Further details and background information are as follows:

The entire Commonwealth of Massachusetts was previously classified as nonattainment for ozone, and was divided into two nonattainment areas. The Eastern Massachusetts Ozone Nonattainment Area included Barnstable, Bristol, Dukes, Essex, Middlesex, Nantucket, Norfolk, Suffolk, and Worcester counties. Berkshire, Franklin, Hampden, and Hampshire counties comprised the Western Massachusetts Ozone Nonattainment Area. With these classifications, the 1990 Clean Air Act Amendments (CAAA) required the Commonwealth to reduce its emissions of volatile organic compounds (VOCs) and nitrogen oxides (NOx), the two major precursors to ozone formation to achieve attainment of the ozone standard.

The CAAA also required Metropolitan Planning Organizations (MPOs) within nonattainment areas to perform conformity determinations prior to the approval of their Regional Transportation Plans (RTPs) and Transportation Improvement Programs (TIPs). Periodically, air quality analyses are conducted on all the RTPs, the purposes of which are to evaluate the RTPs’ air quality impacts on the SIP. Conformity determinations are then performed to ensure that all regionally significant projects are included in the RTPs and the TIPs, and that they meet the air quality goals of the SIP. The Federal Highway Administration (FHWA) – in consultation with the Environmental Protection Agency (EPA New England) and the Massachusetts Department of Environmental Protection (DEP) – confirm and approve these conformity determinations (more details and background of major conformity milestones in recent years are provided in the each MPO’s 2012 Regional Transportation Plan).

In 2002, the cities of Lowell, Waltham, Worcester and Springfield were re-designated to attainment for carbon monoxide with EPA-approved limited maintenance plans. In April 1996, the communities of Boston, Cambridge, Chelsea, Everett, Malden, Medford, Quincy, Revere, and Somerville were classified as attainment for carbon monoxide (CO). Air quality conformity analysis must still be completed in these communities, as they have a carbon monoxide maintenance plan approved into the state implementation plan (SIP). The year 2010 carbon monoxide motor vehicle emission budget established for the Boston CO attainment area with a maintenance plan is 228.33 tons of carbon monoxide per winter day.

The 1970 Clean Air Act defined a one-hour national ambient air quality standard (NAAQS) for ground-level ozone. The 1990 CAAA further classified degrees of nonattainment of the one-hour standard based on the severity of the monitored levels of the pollutant. The entire commonwealth of Massachusetts was classified as being in serious nonattainment for the one-hour ozone standard, with a required attainment date of 1999. The attainment date was later extended, first to 2003 and a second time to 2007.

In 1997, the EPA proposed a new, eight-hour ozone standard that replaced the one- hour standard, effective June 15, 2005. Scientific information had shown that ozone could affect human health at lower levels, and over longer exposure times than one hour. The new standard was challenged in court, and after a lengthy legal battle, the courts upheld it. It was finalized in June 2004.The eight-hour standard is 0.08 parts per million, averaged over eight hours and not to be exceeded more than once per year. Nonattainment areas were again further classified based on the severity of the eight-hour values. Massachusetts as a whole was classified as being in moderate nonattainment for the eight-hour standard, and was separated into two nonattainment areas—Eastern Massachusetts and Western Massachusetts.

In March 2008, EPA published revisions to the eight-hour ozone NAAQS establishing a level of 0.075 ppm, (March 27, 2008; 73 FR 16483). In 2009, EPA announced it would reconsider this standard because it fell outside of the range recommended by the Clean Air Scientific Advisory Committee. However, EPA did not take final action on the reconsideration so the standard would remain at 0.075 ppm.

After reviewing data from Massachusetts monitoring stations, EPA sent a letter on December 16, 2011 proposing that only Dukes County would be designated as nonattainment for the new proposed 0.075 ozone standard. Massachusetts concurred with these findings.

On May 21, 2012, (77 FR 30088), the final rule was published in the Federal Register, defining the 2008 NAAQS at 0.075 ppm, the standard that was promulgated in March 2008. A second rule published on May 21, 2012 (77 FR 30160), revoked the 1997 ozone NAAQS to occur one year after the July 20, 2012 effective date of the 2008 NAAQS.

Also on May 21, 2012, the air quality designations areas for the 2008 NAAQS were published in the Federal Register. In this Federal Register, the only area in Massachusetts that was designated as nonattainment is Dukes County. All other Massachusetts counties were classified as unclassifiable/attainment.

Therefore, conformity for ozone in the each of the Massachusetts MPOs was required until July 20, 2013 for only the 1997 ozone standard. This 2014-17 STIP (as a product of all the MPO TIPs) has not completed its collective development, review, and approval by the Federal Highway Administration until after July 20, 2013 – after this standard has been revoked. As for Martha’s Vineyard (Dukes County), the only Massachusetts region which remained an ozone non-attainment area under the 2008 NAAQS, it is also classified as an “isolated rural area” and as such, for transportation improvement programs composed entirely of exempt projects (40 CFR 93.126), an air quality conformity analysis and determination is also not required.

Martha’s Vineyard / Dukes County has historically programmed – and continues to program – in its TIP only “Exempt” transportation projects as defined in 40 CFR 93.126, so their current FFY 2014-17 Transportation Improvement Program does not require an air quality conformity analysis or determination for the 2008 NAAQS. Nevertheless, the entire list of current projects was reviewed as part of the interagency conformity consultation process, with the interagency group last meeting on June 13, 2013, and reaching a consensus that potential adverse emissions impacts were not associated with any of the subject projects.

For these reasons – an “unclassifiable/attainment” designation for most of Massachusetts currently, plus the fact that the Martha’s Vineyard region has only programmed “exempt” transportation projects, the Commonwealth does not need to perform a conformity analysis or determination for ozone on the current state transportation improvement program.

All the regional TIPs were derived from regional transportation plans that met conformity requirements, and this STIP has been prepared in accordance with EPA’s and Massachusetts’ current conformity regulations. This FFY 2014-2017 Statewide TIP – as a product of all the regional TIPs – has been prepared following all the guidelines and requirements of these rules during this time period.

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