Methane Contamination of Groundwater

In Rachel Carson's Silent Spring, she discussed the negative impacts of pesticides leaching into groundwater.  The negative impacts were mainly seen by their effects on biological systems in the 1960s.  However, currently there is a rising controversy lately over the natural gas industry.  This article describes the recent litigation arising from claims that "fracking" or the extraction of natural gas has led to an increase in methane contamination of groundwater.  As this groundwater is used for drinking, and other daily needs, the controversy has risen over whether this can be proven for a fact or not.