Researchers at Yale University have found that the presence of organic compounds in groundwater aquifers overlying the Marcellus Shale don’t come from deep shale layers or gas wells, according to a release. Instead, the scientists say that the compounds mostly come from surface releases caused by hydraulic fracturing, also known as “fracking.”
Researchers made the find after three years of sample collection from drinking water wells around the Marcellus Shale. All 64 samples they collected were taken from northeast areas of the state across an area equaling around 7,400 square kilometers.
Analysis of the samples revealed that some of them, those taken near natural gas wells, contained low levels of organic compounds. The compounds most likely entered the groundwater supply due to gas extraction operations above, the scientists say, instead of migrating from subsurface areas.