WHAT - Hydrofracking: What Everyone Needs to Know - page 18

had given up on. In the 1980s Mitchell used government mapping tools and oth-
er research to learn how to hydrofrack the Barnett Shale formation. But this shale
formation is complex and drillers were stymied by slow, clogged, inefficient wells.
Mitchell spent 17 years and $6 million to crack the problem, though many told him
he was just wasting his time. It was, says The Economist , “surely the best develop-
ment money in the history of gas.” 12
Having successfully demonstrated multifracture horizontal well drilling,
Mitchell Energy engineers had to develop the optimal combination of in-
puts—water, sand, proppants, chemical lubricants, and so on—to achieve maxim-
um gas recovery at the lowest cost. In 1997, Mitchell Energy developed “slickwa-
ter fracturing,” in which chemicals are added to the water pumped into wells to
increase the fluid flow. The chemicals, some of which are discussed in the next
chapter, had particular functions—friction reducers, biocides, surfactants, and scale
inhibitors—to prevent a well from clogging, keep proppants suspended, and accel-
erate gas pumping. The invention of the slickwater process was the breakthrough
that made shale gas economical, and in 1998 Mitchell tapped huge shale gas re-
serves. The Oil and Gas Journal notes that as a result of Mitchell's refinements of
fracking techniques, a well that produced 70 barrels a day using conventional (ver-
tical) drilling can now produce 700 barrels a day. And a hydrofracture job that once
cost $250,000 to $300,000 now cost about $100,000. Passing this milestone, shale
gas became a commercially viable resource. 13
Mitchell's technology is now used nationwide, both for gas and for shale oil,
which can be extracted from shale beds in the same way gas is. Some wells also
produce valuable liquid natural gases (LNG), such as butane and propane. “We can
frack safely if we frack sensibly,” Mitchell wrote with Michael Bloomberg in the
Wall Street Journal .
Drilling and hydrofracking techniques continue to evolve, and since the 1940s,
roughly 1.2 million wells have employed them in the United States. 14 By 2009,
there were nearly 500,000 active natural gas wells in the United States, double the
number in 1990, and the drilling industry reports that about 90 percent of them used
hydrofracturing (others say the figure could be as high as 95 or even 99 percent. 15 )
The Barnett Shale produces over 6 percent of all domestic natural gas. 16 In
2001, just before the Section 29 production tax credit expired, George Mitchell sold
his company to Devon Energy for $3.5 billion. 17 (He died at age 94, in July 2013.)