in the field, it blew out, spewing enormous quantities of oil and gas into the water from the sea floor. While crews were able to cap the wellhead and relieve the pressure there, the adjacent geologic formations were not strong enough to contain the pressure, and lacking a steel protective casing, the reservoir fluid and gas ripped through the sedimentary sand layers directly on the ocean floor; the result was the 1969 Santa Barbara oil spill of 80,000 to 100,000 barrels, which eventually coated over 40 miles of southern California coastline with oil, an ecological disaster which killed upward of 10,000 birds and numerous sea mammals and other creatures. Following the spill, the Secretary of the Interior ended all offshore oil drilling in the Outer Continental Shelf (OCS) until measures for better oversight were put in place, which happened in 1970 with the passage of the federal National Environmental Policy Act (NEPA), and in California, with the California Environmental Quality Act (CEQA). Opposition to oil drilling was nothing new in Santa Barbara – local residents, led by a newspaper publisher, objected enough to the expansion of the Summerland field in the 1890s to organize a late-night derrick-destroying party near the present-day Miramar Hotel – but the spill intensified the local hostility to oil drilling to the point that few new platforms were installed, and none at all within the 3-mile limit. After the disaster and cleanup, Unocal continued drilling wells from the two platforms that were already in place ("A" and "B", began producing from them in March 1969, and installed two more platforms ("C" and "Hillhouse"). Production from the field peaked quickly, reaching a maximum in 1971, during which year almost 28 million barrels of oil were extracted. The field experienced a gradual decline in production afterwards, approximately 8 percent per year, as is typical of fields when the reservoir pressure declines, and in the absence of secondary recovery technologies (such as water or gas injection). In 1985, Unocal tried waterflooding, and then polymer flooding, to improve production rates, and then in 1990 they began a horizontal drilling program to reach reservoirs impractical to exploit any other way. Unocal continued to produce from the field until they sold all of their California production assets in 1996 to Nuevo Energy, as operated by Torch Energy Advisors. In 1997 Nuevo took over the operations of the four platforms directly, and in