Patent ID: 7644759

Claim:
Apparatus for injecting liquid into porous ground material around a borehole in the ground material; the apparatus includes a pulsing-apparatus, whereby the borehole comprises a pulsing-well; the pulsing-apparatus is operable to periodically and cyclically discharge respective substantial charge-volumes of liquid out of the pulsing-well into the ground material surrounding the pulsing-well; the apparatus includes a saturation-apparatus; the saturation-apparatus is operable to keep the ground material surrounding the pulsing-well saturated with liquid, during operation of the pulsing-apparatus; the saturation-apparatus includes a reservoir of make-up liquid; and the apparatus includes a make-up-apparatus, which is operable to supply make-up liquid from the reservoir into the ground surrounding the pulsing-well, continuously during operation of the pulsing-apparatus.