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Slide 28

The driller pumps compressed air, or water or nitrogen (sometimes mixed with sand) down the production pipe, out through the holes at the bottom and into the gas bearing formation.  He uses enough pressure to actually crack the rock in the gas bearing strata!  Enough pressure to lift all of the rock above it to make the cracks!  For more informaition on fracturing to go the Earnthworks web site.

Surprisingly, this does not usually cause a problem for the surface owner IF, the metal casing and cementing were done properly, and IF the “frac” job is done deep enough in the ground.  If it is done deep in the ground, then the fractures (that may spread beyond the gas bearing strata) do not reach up into strata that could affect the surface owner and the surface owner’s good groundwater. 

Having the fractures extend up that far would be rare in most conventional gas wells that are thousands of feet in the ground.  A fracture would be very unlikely to reach up to where it would bother the surface owner.

However, if there is an old orphaned unplugged well nearby that penetrates the same gas bearing strata, and if the fracing pressure reaches it somehow, that could cause communication up the old unplugged gas well.  The pressure or gas or fluids could rise up the orphaned, unplugged well into shallower strata and cause problems.

Also, if the well being drilled is a “coal bed methane” well into one of the much shallower coal seams, then any errant fractures will be close enough to the surface that they could cause problems.