The Associated Press has found that hundreds of complaints have been submitted about well-water contamination from oil and gas drilling in at least four states experiencing the shale boom.

Pennsylvania had 499 complaints in 2012 and 398 complaints in 2013 alleging that oil and natural gas drilling polluted or otherwise affected private water wells. Pollution was confirmed in more than 100 cases in the last five years, according to the review. Reporter Kevin Begos wrote that this “casts doubts on industry suggestions that such problems rarely happen.”

Since the shale revolution began in the mid 2000s, there has been confusion about how widespread water contamination and problems from drilling really are.

The AP reviewed data of drilling-related complaints in Pennsylvania, Ohio, West Virginia and Texas. The news organization found major differences in how states report such problems.

Texas provided the most detail, but other states, including Pennsylvania, provided only general outlines. “The lack of detail in some state reports could help fuel public confusion and mistrust,” Begos wrote.

Here are some of the AP’s findings:

Pennsylvania has confirmed at least 106 water-well contamination cases since 2005, out of more than 5,000 new wells. There were five confirmed cases of water-well contamination in the first nine months of 2012, 18 in all of 2011 and 29 in 2010. The Environmental Department said more complete data may be available in several months.

Ohio had 37 complaints in 2010 and no confirmed contamination of water supplies; 54 complaints in 2011 and two confirmed cases of contamination; 59 complaints in 2012 and two confirmed contaminations; and 40 complaints for the first 11 months of 2013, with two confirmed contaminations and 14 still under investigation, Department of Natural Resources spokesman Mark Bruce said in an email. None of the six confirmed cases of contamination was related to fracking, Bruce said.

West Virginia has had about 122 complaints that drilling contaminated water wells over the past four years, and in four cases the evidence was strong enough that the driller agreed to take corrective action, officials said.

View the full story here.

Natasha Khan is the energy and environment reporter for PublicSource.

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