Who's responsible for vapors left on a truck after chemical delivery?

[BadReligion]

I work for a company that has developed a chemical filter for chemical vapors that are left on a truck after delivery. Currently, it seems that the vapors are just being released into the air in "safe" spots by the truckers. I know the DOT regulates the trucks when they are "mobile," but who is responsible for the vapors once the chemical payload is delivered? The EPA is starting new regulations in 2005 concerning the transport, storing, and processing of chemicals, but I was wondering if there is anything on the books now?

 

[rbcoulter]

That practice not consistent with my experience. Usually the vapor is exchanged with the storage tank.