Brush fires are something the RR's on Cajon always worry about. Story about a UP engine, brand new, that overheated in one of its engine areas, a small fire broke out. The Forestry Service pounced on it really fast and got it out. Such things are unusual, but could, in itself, start a forest fire. One thing, the CDF is FAST. Interesting to note, some, possibly many, brand new engines, have to be "debugged".