Hydraulic fracking releases ancient radioactive brine

Hydraulic fracking releases ancient radioactive brine: http://knowledgecircle.cifar.ca/exchange/hydraulic-fracking-releases-ancient-radioactive-brine/ "Hydraulic fracturing, or fracking, is a widespread technique used by the oil and gas industry to obtain natural gas from shale rock, a type of sedimentary rock that contains hydrocarbons that cannot be recovered using conventional techniques. The process involves drilling thousands of feet into the Earth’s subsurface and injecting a special mixture of water, sand and chemicals to crack the rock and release the gas.
Since approximately one quarter of the fluid returns to the surface through the process, the chemical composition of the returning fluid is of interest to researchers. Studies have shown previously that the wastewater liquid that flows back after fracking contains elements that were not part of the initial solution."