Ever since the boom in hydraulic fracturing of shale gas formations picked up pace about five years ago, foes of “fracking” have argued that the cracking of shale formations was causing the migration of methane, or natural gas, into drinking water wells and aquifers.
But a new study has cast doubt on that explanation and points to different culprits: faulty drilling and well completion techniques.
That’s both good news — and bad news — for the shale gas business. On the one hand, the study suggests the problem can be fixed and that methane contamination of water wells isn’t an inherent part of the fracking process. Contamination can be minimized with proper drilling techniques, including higher standards for cement well linings and steel casings. “This is relatively good news because it means that most of the issues we have identified can potentially be avoided by future improvements in well integrity,” said Thomas Darrah, the study leader and assistant professor of earth sciences at Ohio State.
On the other hand, with thousands of wells being drilled every year, even a very small rate of failure would mean the steady contamination of a significant number of water wells and aquifers. So far this year, the state of Pennsylvania — home to the prolific Marcellus shale — has issued drilling permits for more than two thousand wells. If just one percent of those had a cement or casing failure, that would mean the contamination of 20 drinking water sources in the state every nine and a half months.
At the moment, it is difficult to say with any certainty how often fracked wells suffer cement or casing flaws and state regulators are hard pressed to accurately monitor all the activity taking place.
Indeed, one area the new study examines is Parker County, Texas, the site of a high-profile lawsuit by an individual, Steve Lipsky, who alleged that fracking wells had spoiled his drinking water. He was also shown in a movie about fracking with flames coming out of his garden hose. The company that drilled that well denied any wrongdoing. The Texas Railroad Commission, which regulates oil and gas drilling, has blamed natural seeps for the contamination of local drinking water.