Fracking is the process of hydraulically injecting a mixture of fluids into naturally forming veins or dikes in rock in order to release petroleum, natural gas, or coal seam gas.  The mixture injected is typically a slurry of water, proppants (including silica sand, resin-coated sand, and man-made ceramics), and chemical additives. Additionally, gels, foams, and compressed gases, including nitrogen, carbon dioxide and air can be injected.   Further, sometimes sand containing naturally radioactive materials are used to measure the fracture trace.  There are alsocontinue reading