 And by my trash day on Tuesday, it was hard. The whole gallon had hardened up and shrunk and looked like a big marshmallow sitting inside the can. If it's an alkyd primer or an oil paint, it could take a couple weeks for it to do that. So know that it's going to be out there for a while. But once it has turned into a solid, it can go legally and morally, it can go in your trash can.