The U.S. Environmental Protection Agency has concluded that hydraulic fracturing, the oil and gas extraction technique also known as fracking, has contaminated drinking water in some circumstances, according to the final version of a comprehensive study first issued in 2015.

The new version is far more worrying than the first, which found “no evidence that fracking systemically contaminates water” supplies. In a significant change, that conclusion was deleted from the final study.

Read the report in the New York Times: http://www.nytimes.com/2016/12/13/us/reversing-course-epa-says-fracking-can-contaminate-drinking-water.html