Range over an area in a clean-up operation (5)
I believe the answer is:
scour
'range over' is the definition.
(thesaurus)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for scour that I've seen before include "purge" , "Turn upside down" , "Rub hard or search thoroughly" , "Clean by scrubbing" , "flush out" .)