After currently proved reserves are produced by conventional methods, nearly two-thirds of the known domestic oil resource --- more than 300 billion barrels --- could be abandoned in reservoirs in the Lower-48 United States. This resource is not economically recoverable with currently available technologies. Production of any meaningful portion of this oil will require both adequate oil prices and technology advances in such areas as reservoir description and secondary and tertiary recovery. Cost-effective application of such new or improved technologies now depends largely upon the use of existing wells as points of access to the reservoirs containing the remaining oil resource. Existing US wells, however, are being plugged and abandoned at record rates, which impairs economic access to this remaining resource. This study was designed to estimate the amount of known remaining oil resource associated with abandoned wells and to project future abandonments as a function of oil prices. 5 figs., 2 tabs.