About This Special Issue
Shale oil and natural gas extractions by hydraulic fracturing (fracking) of unconventional horizontal wells are leading US to self-sufficiency in energy. Environmental concerns are raised on the deep-well injection processes leading to chemical and radiological contaminations, and even to seismic disturbances. Implementation of advanced technologies and testing methodologies for analyzing and treating surface wastes can ensure sustainable oil and gas productions with safeguards for a clean environment. With large shale deposits discovered in South America, Europe and Asia the impacts of shale fracking on energy and environment are of critical global importance.