Suddenly, the United States has natural gas to spare. How did that happen?
BY JESSE ROMAN
A DECADE AGO, the U.S. Energy Information Administration (EIA) predicted that by 2016 the U.S. would need to import about 25 percent of its daily natural gas requirements to keep up with demand. By last year the EIA had a much different outlook: the U.S., it said, would be a net gas exporter in 2017, and would ship as much as 10.3 trillion cubic feet (tcf)—more than a third of our current yearly domestic consumption—by 2040.
In each of the last five years, including 2015, U.S. gas producers exceeded all previous annual records for gas supplied to the market, according to the EIA, with last year’s haul totaling 26.5 tcf. Put in context, the entire U.S. used about 27.5 tcf of gas in 2015, the EIA says, including gas for power generation, manufacturing, transportation, shipping, heating homes and businesses, cooking, and more.
The majority of that extra gas comes from large shale fields that lie beneath portions of the United States. The shale formed hundreds of millions of years ago, before the age of the dinosaurs, when large swathes of the continent was covered by ocean; over millennia, small rock particles and organic sentiment collected in layers on the ocean floor, compressing and hardening, and eventually forming massive slabs of shale rock that held trapped methane gas. Scientists and energy prospectors have known for decades about the gas deposits across the country encased in small pockets of impermeable shale—including the Marcellus Formation, which stretches from Tennessee to upstate New York—but until recently the gas was considered economically unviable for extraction.
That began to change about a decade ago with the development of a pair of innovative methods to access the gas. Hydraulic fracturing, or fracking, injects a mixture of water, chemicals, and sand under very high pressure to crack the shale and release the trapped gas. Horizontal drilling involves dropping a well thousands of feet down into the shale layer, then thousands of feet sideways, exposing more of a gas-rich rock layer and making it possible to access multiple gas deposits with a single well. These coordinated drilling techniques were refined at the Barnett Shale fields of Texas in the early 2000s, and are now used throughout Texas and in numerous other shale fields across the country. The drilling has sparked outrage from residents and environmentalists who blame fracking for contaminating water supplies and underground aquifers, and for causing small earthquakes. Many proponents, however, consider fracking perhaps the most significant innovation so far this century.
In either case, it’s hard to deny the dramatic impact of the new extraction techniques on world energy supplies. Shale gas now accounts for 44 percent of gross U.S. natural gas production, up from 22 percent in 2010 and 8 percent in 2007, according to EIA figures. The Marcellus Formation area is now one of the largest and most prolific producing natural gas deposits in North America, with an estimated 141 tcf of technically recoverable gas, according to a 2012 EIA estimate.
NFPA does not have codes that specifically address oil and gas drilling sites, but a number of documents contain provisions that can be applied to drilling sites and oil and gas infrastructure. NFPA 30, Flammable and Combustible Liquids Code, for example, describes how fuel storage tanks must be constructed and how close they can be sited to buildings and roads. The Occupational Safety and Health Administration lists 10 NFPA codes and standards that apply to oil and gas drilling sites.