The coal load spraying deal was actually started by the railroads themselves -- WITHOUT any greenies involved. BNSF & EwePee were having problems with coal dust blowing off onto trackage in the Powder River Basin and fouling the ballast. In the winter the dust, once wetted down by rain & snow, would freeze in the ballast, preventing water runoff and playing havoc with track alignment & subgrades. So the railroads and the coal mines worked together to install the sprayers right at the loadouts.