In addition to retrofitting 312 on-road and off-road vehicles and equipment with diesel oxidation catalysts, either stand alone or in concert with a closed crankcase ventilation system, the Alabama Department of Transportation (DOT) has implemented a fleet replacement program.  This program auctions off older model diesel vehicles to fund the acquisition of vehicles and equipment that meet 2007 and 2010 diesel emission standards.  Alabama DOT currently has 1256 alternative fuel vehicles in its fleet and through the development of infrastructure to enable the use of the alternative fuels, has purchased 642,708 gallons of E85 and 1,231,385 gallons of B-20 biodiesel from 2007-2011.  They have deployed GPS units in two thirds of their vehicles to help ensure accountability with the implementation of their no idle policy.