For GSS Energy Use chapter 3. Excerpt: Duke University study ...examined the water discharged from Josephine Brine Treatment Facility [in] western Pennsylvania ....Radioactive brine is naturally occurring in shale rock and contaminates wastewater during hydraulic fracturing... Radium levels in samples collected at the facility were 200 times greater than samples taken upstream.... http://www.theguardian.com/environment/2013/oct/02/dangerous-radioactivity-fracking-waste-pennsylvania. Felicity Carus, The Guardian.