The Environmental Protection Agency (EPA) has been cracking down on emission regulations, hitting almost every company with a fine for violating the Clean Air Act. The most recent company to get hit with penalties has been eBay, despite having made attempts to avoid it. But now things are moving into the heart of the diesel industry. Cummins, known for building fantastic diesel engines that can be found within several trucks (specifically Ram) is facing the largest Clean Air Act civil penalty in history, and the second largest environmental penalty in American history, for allegedly installing…