If the EPA gets involved, it is with the service company. Typically these companies bring a 55 gallon drum of solvent with a motorized pump and basin on top. Any solvent used drains back into the drum and the company comes and changes it with a fresh one each month. For a fee.
I have never checked on our zoning. The back half of our building was a Studebaker dealer/repair shop at one time, I’ve been told.