The EPA is definitely not sleeping at the wheel. They spend an enormous effort threatening auto hobbyists with fines and legal action (https://www.hotcars.com/car-tuners-furious-about-epa-emissio...). All over 0.01% of DIYers that want to work on their own cars, in many cases making the cars cleaner by swapping in a more modern engine.

But hey now, contaminate an entire town with toxic industrial chemicals..you get a slap on the wrist. It’s pretty obvious what their agenda is, and it has nothing to do with the environment.