05.07.2009
Extra hole drilled beyond the target of the well. When drilling to a target depth in a well, one would drill a few meters past the target to allow tools and casing to cover the target zone completely
The measured distance (rate/speed) that the drill bit or other drilling tool penetrates subsurface formations in a unit length of time.
A rate class is a group of customers which is distinguished by the rate that this group pays for service as opposed to the actual customer class in which they would otherwise belong