In less than a generation, the United States has soared to world leadership in extracting natural gas from shale formations by hydraulic fracturing. But as the world debates whether “fracking” is an economic boon or a budding environmental disaster, few foreign countries are following the U.S. lead.
Conditions unique to the United States have encouraged investment in the abundant source of low-carbon energy and boosted prospects for reducing dependence on costly and unpredictable supplies of foreign oil. Of the natural gas consumed in the United States last year, 94% came from domestic production, according to the U.S. Energy Information Administration.
“The availability of large quantities of shale gas should enable the United States to consume a predominantly domestic supply of gas for many years and produce more natural gas than it consumes,” the agency reports, predicting a 29% increase in output by 2035, almost all of it from shale fracking.
The rapid advance toward self-sufficiency has made the U.S. industry both a model and a cautionary tale for other countries pondering all-in development of their shale-gas reserves.
Significant deposits of natural gas trapped in coal and shale seams have been identified in Eastern and Western Europe, Canada, Australia, China, South Africa and the cone of South America. Global energy giants like Shell and Chevron are bankrolling billions in exploration, sizing up the cost-effectiveness of replicating the U.S. boom in more remote locales with little infrastructure.
Technological advances in horizontal drilling have made it feasible to tap small pockets of gas trapped in shale layers a mile or more below the surface. Contractors bore thousands of feet down through soil, rock and water layers, then drill laterally through the shale to create a horizontal well. When sand, water and chemicals are blasted into the bore holes, the force fractures the shale, releasing gas from fissures within the sedimentary rock. The gas is captured and ferried by pipeline to distribution grids or to port facilities where it can be converted to liquefied natural gas for overseas shipment.
But the process leaves behind tons of chemical-contaminated mud. There are also reports of drinking water pollution from the chemicals and methane gas that escapes into underground reservoirs. A study last year published by the Proceedings of the National Academy of Sciences documented “systematic evidence for methane contamination of drinking water associated with shale gas extraction” in the aquifers above the Marcellus and Utica shale formations in the U.S. Northeast. This spring, the U.S. Geological Survey reported “a remarkable increase” in the occurrence of earthquakes of magnitude 3 or larger that it tied to fracking operations.
This month, the U.S. Government Accountability Office acknowledged that the Environmental Protection Agency was finding it “challenging” to inspect and enforce clean air and clean water regulations in the fast-moving fracking industry. For example, the GAO report noted, the EPA is often unable to evaluate alleged water contamination because investigators lack information about the water quality before the fracking occurred.