A new test has been developed to check for contamination of shallow groundwater from modern gas extraction techniques, such as hydraulic fracturing, commonly known as fracking.

That can be good or bad. In 2016, we can detect almost anything, which has been a boon for environmental lawyers but does a real disservice to the public, who are confused about the detection of a hazardous chemical versus their actual risk. The International Agency for Research on Cancer (IARC), for example, has declared red meat as hazardous as plutonium and cigarette smoking, but of course the actual risk to humans is in the noise range compared to a vegetarian diet. Natural gas has caused greenhouse gas emissions to plummet and environmental groups have been searching for a way to implicate hydraulic fracturing as harmful and the way to do it is using a similar hazard, without discussing risk. 

There have been allegations about ground water, but so far they have been unfounded. Methane is natural and that is in some water sources and some activists have faked results for dramatic effect. 

Still, scholars say a test is needed and have developed a new way to "fingerprint" methane gas by identifying tiny traces of inactive natural gases, known as noble gases. These fingerprints vary depending on the origin and depth of the methane, and enable scientists to pinpoint its source. The researchers, from the Universities of Edinburgh and Glasgow and the Scottish Universities Environmental Research Centre, have recorded these fingerprints in a number of exploratory shale gas and coal bed methane wells from around the UK. 

The fingerprint analysis can be used to determine the origin of methane at exploration sites. If levels of methane in groundwater are found to have changed following exploration activity, and the gas is traced to exploration or extraction activity, appropriate action can be taken. Scientists developed the test by adapting a technique used for monitoring potential leaks of carbon dioxide gas from storage sites deep underground.

Dr Stuart Gilfillan, of the University of Edinburgh's School of GeoSciences, who led the project, said: "Creating this fingerprint test will enable gas exploration and extraction to be carried out responsibly and should help address public concerns over this technology. It is important that careful monitoring of methane levels in nearby waters is carried out when commercial extraction begins."