Geology Reference
In-Depth Information
face; well blowouts; exposure to naturally-occurring radioactive nuclides; the mi-
gration of gas or other fumes into the air; contamination of food supplies; ad-
verse health effects in man and animals; and earthquakes caused by the injection
of wastewater into fault zones. Less quantifiable but still significant is the social
impact of fracking—that is, what happens when rural landowners become rich,
or don't, by leasing their property to frackers; the impact on small communities
when thousands of roughnecks suddenly appear to frack wells, then just as sud-
denly leave when the job is done; or the consequences of having hundreds of big
trucks rumbling on country roads and dozens of noisy, brightly lit drill rigs operat-
ing 24/7.
As we've seen, water constitutes the largest component of fracking fluid by far, so
it is not surprising that questions about the quantity and quality of water used by
drillers have been contentious.
Opponents have expressed three main concerns about water. First, they worry
that hydraulic fracturing uses so much H
2
O—about 5 million gallons per well, on
average—that it can deplete groundwater supplies faster than nature can recharge
the amount of water an aquifer—an underground water supply—regains each year
from precipitation and runoff.) Second, the injection of chemicals—some of them
toxic—underground at extreme pressures raises fears of chemical spills on the sur-
face and consequent contamination of water supplies below ground as those chem-
icals seep into the fractured rock. Third, the safe disposal of fluid and “produced
water” (groundwater that is brought to the surface in the course of drilling) re-
mains a challenge, and has occasionally caused minor earthquakes when injected
into geologic fault zones.
Because hydrofracking is new to many regions, legislators and regulators are
scrambling to catch up with these issues—with, as we shall see, varying degrees of
success.
