I looked, but I don't see anything like that. The exclusions for smoke and water damage do not apply to "sudden and accidental" losses but the pollution one does. And it does not limit it to contamination of the environment.

My Erie policy was emailed to me, but here is a State Farm policy (not the one I quoted above) that has a similar exclusion:

http://www.opic.texas.gov/images/TDI_Approved_Policy_Forms/S...

That said, from googling I gather that there has been a lot of litigation over what counts as a "pollutant," including specifically whether gasoline counts. So I don't think that the presence of this clause means that an insurance company will always try to exclude any losses involving gasoline. I just think maybe they would have an argument if they wanted to.