America's oil reserves dropped to their lowest level in 37 years this year because of a sharp decline in the drilling of new wells, a study by the Congressional Research Service found. The study, released by Sen. Lloyd Bentsen (D-Tex.), estimated that accessible oil in the ground in 1987 was 25.4 billion barrels--the lowest level since 1950--and put 1987 production at 2.8 billion barrels, the lowest since 1965. Bentsen said the study confirms fears that the United States is becoming "overly dependent" on foreign oil. Although large new oil fields are not expected to be found in onshore producing regions, they "may exist offshore from California, in the Gulf of Mexico and in certain regions of Alaska, such as the Arctic National Wildlife Refuge," the study said. Bentsen is urging an import fee on foreign oil to encourage increased domestic production.