The Costs of Fracking

as for any pipelines needed to deliver gas
to market.
Materials Assembly
Hydraulic fracturing requires massive
amounts of water, sand and chemicals—all
of which must be obtained and delivered
to the well site. Water for fracking comes
either from surface waterways, groundwater
or recycled wastewater from previous
fracking activities, with millions of gallons
of water required for each well. The
special grade of sand used in fracking must
be extracted from the ground—often from
silica mines in the upper Midwest—and
transported to the well site. Water, sand
and other materials must be carried to
well sites in trucks, tearing up local roads,
creating congestion, and producing local
level air pollution.
Drilling and Hydraulic Fracturing
Once the necessary machinery and materials
are assembled at the drilling site,
drilling can begin. The well is drilled to
the depth of the formation that is being
targeted. In horizontally drilled wells, the
well bore is turned roughly 90 degrees
to extend along the length of the formation.
Steel “casing” pipes are inserted to
stabilize and contain the well, and the
casing is cemented into place. A mix of
water, sand and chemicals is then injected
at high pressure—the pressure causes the
rock formation to crack, with the sand
propping open the gaps in the rock. Some
of the injected water then flows back out
of the well when the pressure is released
(“flowback” water), followed by gas and
water from the formation (“produced
water”).
Equipment is put in place in preparation for hydraulic fracturing at a well site in Troy, Pa. In
hydraulic fracturing, a combination of water, sand and chemicals is injected at high pressure to
fracture oil or gas-bearing rock formations deep underground. Credit: New York Department
of Environmental Conservation
Fracking: The Process and its Impacts