From EARTH Magazine  --  Since hydraulic fracturing operations began in the Marcellus Shale region, debate has raged over whether drilling operations are causing high levels of methane in drinking-water wells. But few systematic scientific studies have been published to date, so it's unknown if high methane levels are natural or the result of contamination from nearby gas wells. Now, a new study is adding some much-needed baseline data for methane levels in groundwater in New York.