In at least four states that have nurtured the nation's energy boom, hundreds of complaints have been made about well-water contamination from oil or gas drilling, and pollution was confirmed in a number of them, according to a review that casts doubt on industry suggestions that such problems rarely happen.
Drilling-related complaints in Pennsylvania, Ohio, West Virginia and Texas and found major differences in how the states report such problems. Texas provided the most detail, while the other states provided only general outlines. And while the confirmed problems represent only a tiny portion of the thousands of oil and gas wells drilled each year in the U.S., the lack of detail in some state reports could help fuel public confusion and mistrust.
The AP found that Pennsylvania received 398 complaints in 2013 alleging that oil or natural gas drilling polluted or otherwise affected private water wells, compared with 499 in 2012. The Pennsylvania complaints can include allegations of short-term diminished water flow, as well as pollution from stray gas or other substances. Since 2005, 106 cases of pollution were confirmed in Pennsylvania out of more than 5,000 new wells.
Texas hasn’t confirmed any cases of drilling-related contamination from oil and gas activity in the past 10 years. Out of nearly 200 drilling-related pollution complaints in the past three years, Ohio said it had six confirmed cases of contamination, all unrelated to fracking. West Virginia reported 122 complaints, with four cases where the evidence was strong enough that the driller agreed to take corrective action, state officials said.
Over the past 10 years, hydraulic fracturing, or fracking, has led to a lucrative boom in oil and natural gas production around the country, but it has but also created pollution fears.
Extracting fuel from shale formations requires pumping hundreds of thousands of gallons of water, sand and chemicals into the ground to break apart rock and free the gas. Some of that water, along with large quantities of existing underground water, returns to the surface, and it can contain high levels of salt, drilling chemicals, heavy metals and naturally occurring low-level radiation.
But some conventional oil and gas wells are still drilled, so the complaints about water contamination can come from them, too. Experts say the most common type of pollution involves methane, not chemicals from the drilling process.
The Associated Press