Patent ID: 8807217

Claim:
A method for using rock debris or removing unused rock debris from a bored passageway through subterranean strata using at least one rock breaking apparatus, said method comprising the steps of: providing a fluid slurry communicated toward a lower end of at least one conduit string placed within a proximal region of an unlined portion of said passageway through subterranean strata containing an inventory of rock debris; circulating said fluid slurry from said proximal region to urge at least a portion of said inventory of rock debris for use within or removal from said passageway through subterranean strata; and providing said at least one rock breaking apparatus engaged with said at least one conduit string and placed in said proximal region of an unlined portion of said passageway through subterranean strata with at least one member adapted to increase a volume of reduced particle size rock debris generated by increasing a frequency of impact and an associated breakage of said inventory of rock debris within said proximal region per revolution of said at least one conduit string, per volume of fluid slurry circulated, or combinations thereof, wherein a used volume of rock debris coats an unlined strata wall of said passageway to inhibit strata fracture initiation or propagation and an unused volume of rock debris is urged from an upper end of said passageway at an increased rate by an associated reduction in fluid slurry suspension or velocities to urge said reduced particle size rock debris from said passageway, through said unlined portion having an improved pressure integrity produced from inhibiting said initiation or propagation of strata fractures.