Gas Leaks in Fracking Disputed in Study

Drilling for shale gas through hydraulic fracturing, or fracking, appears to cause smaller leaks of the greenhouse gas methane than the federal government had estimated, and considerably smaller than some critics of shale gas had feared, according to a peer-reviewed study released on Monday. The study, conducted by the University of Texas and sponsored by the Environmental Defense Fund and nine petroleum companies, bolsters the contention by advocates of fracking — and some environmental groups as well — that shale gas is cleaner and better than coal, at least until more renewable-energy sources are developed. More than 500 wells were analyzed. The Texas study concluded that while the total amount of escaped methane from shale-gas operations was substantial — more than one million tons annually — it was probably less than the Environmental Protection Agency estimated in 2011.  In particular, it indicated that containment measures captured 99 percent of methane that escaped from new wells being prepared for production, a process known as completion. The Environmental Protection Agency has begun to require drillers to control leaks during completions, which are believed to be one of the major sources of methane losses at fracking wells. Although controls will not be required until January 2015, a number of companies already capture escaped gases at wells being prepared for production. The report comes at a time when shale-gas drilling is growing at a breakneck pace — production, now 30 percent of all United States natural gas, is expected to reach 50 percent by 2040 — but also when the industry is beset by controversy. The Texas study is the most comprehensive look to date at a contentious issue in the debate over fracking: the extent to which methane leaks during drilling and production offset the environmental benefits of the clean-burning natural gas the wells produce...more