The Department of Environmental Quality proposed amendments to R307-121, General Requirements: Clean Fuel Vehicle Tax Credits. The amendments would add additional language requiring the purchase date and price of compressed natural gas vehicles; add a new subsection addressing the eligibility requirements for vehicles that meet air quality and fuel economy standards; add a new subsection that addresses the eligibility requirements for vehicles converted to electricity; and add definitions for "air quality standards," "fuel economy standards," "motor vehicle," and "original purchase" to the rule. http://www.rules.utah.gov/publicat/bull_pdf/2008/b20081001.pdf pp. 25-27.