Environmental releases from exploration and production operations in Oklahoma: Type, volume, causes, and prevention

A total of 16,906 recent fluid releases were reported to the Oklahoma Corporation Commission (OCC) during the 10-yr period from 1993 to 2003. Of these, 12,863 were identified as exploration- and production-related releases of oil or saltwater from identified geographic areas. The primary reported origins of oil and saltwater releases were leaks from lines, tanks, wellheads, surface equipment, and pits. Important reported causes of fluid releases range from common overflows (tank, pit, and dike), intentional dumping or other illegal activity, storms, fires or explosions, accidents (including the actions of livestock), and to occasional corrosion. Approximately 34% of all recent oil or saltwater releases resulted in reported injury to environmental receptors (surface water, crops or livestock, soil, fish, or wildlife). For the 10-yr period of record, 41% of all exploration and production complaints to OCC involved the release of oil or saltwater. On an annual basis, complaints involving the release of fluids decreased from 65.8% in 1993 to 46.1% in 2002. Releases specifically identified as involving oil or saltwater comprised 76.1% of all fluid releases. Quantified releases of oil had a median volume of 10 bbl, whereas quantified releases of saltwater had a median volume of 40 bbl. For those releases in which the volume of both oil and saltwater were quantified, the volume of saltwater spilled was approximately 76% of the total volume.