I have been working a a house that is heated with fuel oil and the tank fill fittings leak. The result is a 275 galllon steel tank coated on the outside with dust and fuel oil of many years neglect. This morning I tried two methods for cleaning. The first involved a hand towel and full strength Spic and Span liquid cleaner. I spread the towel and poured on the cleaner to wet the towel and left it to soak for an hour or two. It was very effective, taking the crud off right down to the primer paint. The second method used Easy-Off oven cleaner "No Fumes" and no sodium hydroxide. That also worked very well around the pipe fittings.
I have no idea what the EPA response would be but in a poorly ventilated basement it was not unpleasant. The wash water is nasty looking I wouldn't pump it over board.
I have no idea what the EPA response would be but in a poorly ventilated basement it was not unpleasant. The wash water is nasty looking I wouldn't pump it over board.