Volkswagen has been hit with at least 16 putative class actions around the country in the wake of the Environmental Protection Agency’s announcement that the company programmed software in cars with diesel engines to evade clean air standards.

The suits were filed Sept. 21, following the EPA’s Sept. 18 notice of violation, which said the company designed certain 2009 through 2015 cars with 2.0 liter diesel engines that detect when they are being inspected for emissions, but bypass elements of the vehicles’ emissions control systems during normal operation. The allegations concern roughly 482,000 cars, whose emissions levels are 10 to 40 times greater than the law allows, the EPA said.