epa03163508 (01/20) A hydraulic fracturing drill rig lights up the landscape at dusk near Troy, Pennsylvania, USA, 08 March 2012. The controversial drilling practice, also known as fracking, requires injecting huge amounts of water, sand, and chemicals at high pressure thousands of feet beneath the earth’s surface to extract reserves of natural gas. EPA/JIM LO SCALZO PLEASE SEE ADVISORY epa03163507 FOR FULL FEATURE TEXT +++(c) dpa – Bildfunk+++