You know, I was at yellowstone this summer and the immensity of the place really struck home. It is a sham for these enviro Nazis to take pollution readings at the ONLY freekin entrance to the place, where everyone is warming up the sleds, idling, etc. and then say pollution levels in the park are too high.
It would take every damn sled and PWC in the entire country to bring the air quality of the park down to that of your average city, and they would all have to be there at the same time. And since the sleds are kept to the roads, they don't even do any damage to the ground.
They also talk about disturbing the wildlife-I had a damn buffalo standing outside my cabin one morning-wouldn't even move when we walked by it. (Guess it's lucky he was in a good mood)