The Circuit Court of Cook County, Illinois ruled that gas combustion electric generators that are used in a mandated landfill gas emission project are exempt from sales tax as pollution control equipment.

The Court contended that the Department of Revenue already acknowledged the collection piping, pumps and compressors used to collect the landfill gas qualified for an exemption. They also stated that the equipment used to dispose of the landfill gas, once it is collected is a necessary and integral part of the landfill gas collection and control systems. (Waste Management of Illinois vs. Illinois DOR)