I don't see a problem with the pollution aspects - how many gallons of fuel do cars burn a year inside Yellowstone? I'd bet it's a lot more. The problem is the noise, which I agree could have been solved. Unfortunately they missed their opportunity to solve it and now they'll get it solved for them. And such is government...

__________________
1982 Mercedes-Benz 300CD
1982 Mercedes-Benz 240D - stick