The Arizona Department of Environmental Quality (ADEQ) commissioned a comprehensive analysis, in which MathPro Inc. participated, of the cost, supply, and vehicle emissions effects of Arizona’s adopting the California CARB 3 gasoline standard in the Arizona Cleaner Burning Gasoline (AZ CBG) program. At that time, the AZ CBG program called for either CARB 2 gasoline (CBG 2) or a federal RFG “look-alike” (CBG 1).

The objective of the study was to evaluate CARB 3 gasoline and various other possible gasoline formulations with respect to their prospective cost, likely effects on gasoline supply to the affected area (Area A, including the Phoenix metropolitan area), and estimated effects on vehicle emissions and emissions inventories – all relative to the current program.

The study addressed both winter and summer gasoline standards. The target years for the analysis were 2010 and 2015.

MathPro Inc. served as a subcontractor on the project team, responsible for the refining analysis segment of the study. In this capacity, MathPro Inc. conducted a detailed technical and economic analysis of gasoline supply to Maricopa County, from the Los Angeles, West Texas/New Mexico, and Gulf Coast refining centers. The analysis encompassed (i) establishing baseline gasoline properties and emissions (as registered by the Complex Model), reflecting actual gasoline supplies in the 2004 winter and summer seasons; (ii) estimating the average properties of CARB 3 and other candidate gasoline types that would be delivered to the area; (iii) assessing the effects of each gasoline type on the gasoline distribution system serving the area and surrounding areas; and (iv) analyzing the technical and economic implications of producing CARB 3 gasoline and other candidate gasoline types in the various refining centers that supply the area.

Results of the analysis informed ADEQ’s recommendations and actions regarding the change in Arizona’s CBG program.