An interesting read about some not-so-routine trains.
http://www.philly.com/philly/busine..._cleaning_leaves_from_the_Regional_Rails.html
Water dribbled, a nozzle spun faster, and then, for a few minutes, the trickle became a jet, roaring as it blasted the tracks beneath a train.
<snip>
Oozing from a pipe a few feet farther along the train was a milky solution of sand, tiny metal beads, and oil that ran like melting ice cream over the rail.
http://www.philly.com/philly/busine..._cleaning_leaves_from_the_Regional_Rails.html