Trains or buses are much less polluting than planes.
colliery spoil is polluting the water at the bottom end of the lake.
resurges just below the twin entrances, making an ideal spot for skinny dipping (and polluting the locals water supply ).
For a long time no carts or carriages were permitted to enter the city for fear of polluting and injuring the pavement, and the transport of goods was carried on in hand-carts.
despoliation of the environment more easily than workers in the polluting industries themselves?