Petroleum refining began within the Greenpoint area in 1866. More than 50 refineries had been established along Newtown Creek by 1870. Refinery operations ceased in 1966, and petroleum bulk storage discontinued in 1993 on the ExxonMobilowned properties of the former refinery parcels. British Petroleum began operation of a bulk fuel storage terminal in 1969, which continues to operate today. On September 2, 1978, the U.S. Coast Guard discovered an oil spill entering the Newtown Creek from Meeker Avenue. In 1979, an investigation of the spill beneath the Greenpoint area determined the release to be approximately 52 acres, with the total spill volume consisting of approximately 17 million gallons of petroleum products. An EPA study of the site in 2007 estimated the size of the spill was potentially much larger than the original estimate. Perhaps well over 30 million gallons comprised the “free product” plume underneath Greenpoint. Comparatively, the size of the Exxon Valdez oil spill of 1989 (considered one of the worst spills in U.S. history) was estimated at 10.9 million gallons. Since 1979, subsurface petroleum product remediation has occurred at multiple sites in Greenpoint. As of 2006, approximately 9.5 million gallons of product had been recovered from the plume area. Additional studies of the plume have revealed that its reach goes deeper into residential neighborhoods than previously believed. Further complicating matters, a May 2009 study of the area discovered residual toxic pollution from dozens of former and current businesses, including dry cleaners, manufacturers, metal works, and storage facilities.