Hinkley Groundwater Contamination refers to the pollution of groundwater in Hinkley, California, primarily caused by the release of chromium-6 from a nearby Pacific Gas and Electric Company (PG&E) compressor station. This toxic substance leached into the groundwater, affecting local drinking water supplies and raising health concerns among residents. The contamination was first discovered in the 1980s, leading to extensive investigations and legal actions against PG&E. The company eventually settled with affected residents, agreeing to pay for cleanup efforts and provide compensation. Ongoing monitoring and remediation efforts aim to restore the groundwater quality in the area.