(V): By the time that pollution reaches the west coast most of it is gone... dissipated in the air and washed from the sky into the pacific ocean. The only "pollution" we've had to deal with lately is debris from last years Japanese tsunami.

I saw something in the news about dust from a Chinese dust storm reaching the west coast... which is pretty remarkable, since dust from our own dust bowl disaster (before I was born) only made it as far as a few miles past the atlantic coastline.