MEMORANDUM

TO : Board of Environmental Protection FROM : Jeff Crawford, Bureau ofAir Quality DATE: April 16, 2009 RE: Post to Public Hearing: Chapter 131 Cutback Asphalt and Emulsified Asphalt Statutory andRegulatory Reference: A . Statutory authority. 38 MRSA Section 585-Aprovides that the Board ofEnvironmental Protection "may establish and amend regulations to implement ambient air quality standards and emission standards. These regulations shall be designed to achieve and maintain ambient air quality standards and emission standards within anyregion andprevent airpollution." B. Specific legal mandates requiring adoption. Section 184ofthe Clean Air Act requires states to implement or update reasonably available control technology (RACT) controls on all major VOCand NOx emission sources and on source categories covered by a control technique guideline document . EPA developed a control technique guideline (CTG), Control ofVolatile Organic Compoundsfrom

the Use of CutbackAsphalt (1977), covering cutback and emulsified asphalt paving operations. Location/Applicability: The proposed regulation will apply statewide. Description: Background: Section 184of the Clean Air Act requires states to implement or update reasonably available control technology (RACT) controls on all major VOCand NOx emission sources and on source categories covered by a Control Technique Guideline (CTG) document . EPA defines RACT as the lowest emission limit that a particular source is capable of meeting by the application of control technology that is reasonably available considering technological and economic feasibility. In December 1977, EPApublished a CTGfor the use ofcutback asphalt which recommended replacing cutback asphalt binders with emulsified asphalt during the ozone season. Since asphalt paving operations occur predominantly during warmweather, whenformation of ozone is most prevalent, the decreased use of cutback asphalt greatly reduces the

VOCemissions frompaving operations. Asphalt used for paving is grouped into three general categories: hot-mix, cutback and emulsified. Hot-mix asphalt, the most commonly used asphalt, produces minimal VOC emissions because its organic components have high molecular weights and low vapor pressures. Cutback asphalt has traditionally been used as a tack coat between old and new layers of hot-mix asphalt, in seal operations, in priming new roadbed for hot-mix applications and cold-mix applications for pavement repair. In preparing cutback asphalt, asphalt cement is blended or "cut back" with adiluent, typically from25 to 45 percent by volume ofpetroleumdistillates, depending onthe desired viscosity. Emulsified asphalt is now used in most ofthe same applications as cutback asphalt, but is a lower VOCalternative to cutback asphalt. Instead of blending asphalt cement with petroleumdistillates, emulsified asphalts use a blend ofasphalt cement, water and an emulsifying agent. Discussion: The Department is proposing these amendments as part of its effort to satisfy the RACT requirements mandated under the CAAand regulations related to the 1997 8-hour ozone NAAQS. According to the EPA's Final Rule to Implement the 8-Hour Ozone NAAQS (70 FR 71612, November 29, 2005), areas classified as "moderate" nonattainment or higherl must submit a demonstration, as a revision to the SIP, that their current rules fulfill 8-hour ozone RACT requirements for all CTGcategories and all major, non-CTGsources. This demonstration canbe made with either a new RACT determination or a certification that previously-required RACT controls represent RACT for the 8-hour ozone NAAQS. For those cases in which states have new

stationary sources not covered by existing RACT regulations, or when new data or technical information indicates that apreviously adopted RACT measure does not represent a newly-available RACT control level, states are required to update their rules. As part of its 8-hour ozone RACT review, Maine has determined that its previous asphalt paving regulations no longer constituted RACT under the 8-hour ozone standard. Chapter 131 was originally adopted in 1993, and was based on 1977 and 1979 CTGs published by EPA . Maine's regulation, Chapter 131 Cutback Asphalt and Emulsified Asphalt, prohibited the use of cutback asphalt on public roads during the ozone season, but allowed for a number of exemptions. As part of the regional effort to address the Federal 1997 8-hour NAAQS for ozone, the OTC commissioned a study (MACTEC Report February 2007) to quantify the emission reduction benefits frompotential new controls, which they deemed to be reasonable. The Department's proposed amendments are based on the OTCcontrol measure summary (which serves as guidance to OTCmember states to use to develop rules), included in the MACTECReport and RACT regulations in other northeast states. Maine is proposing to amend its Chapter 131 Cutback and Emulsified Asphalt rule to prohibit the use of cutback asphalt during the ozone season and limit the use of emulsified asphalt to that which contains not more than 6 .0 ml ofoil distillate (as determined using the American Society for Testing and Materials Methods or American Association of State Highway and Transportation Officials Methods) for all asphalt paving activities.

1 Because Maine is included in the OTCunder section 184 ofthe CAA, the RACT requirements apply statewide.Environmental Issues:

Volatile organic compounds contribute to ground-level ozone formation or smog which aggravates respiratory ailments such as asthma, bronchitis, and emphysema. The presence of ozone impedes the breathing of even healthy people. Departmental Recommendation: The Department recommends that the Board hold a public hearing on this proposal on June 1$, 2009. Estimated Time of Presentation: 15 minutes