Office of Petroleum Reserves Fossil Energy's Petroleum Reserves Website 727-million-barrel underground cache Fossil Energy's Petroleum Reserves Website petroleum reserves 727-million-barrel underground cache 727-million-barrel underground cache 727-million-barrel underground cache 727-million-barrel underground cache Site information 727-million-barrel underground cache 727-million-barrel underground cache Fossil Energy's Petroleum Reserves Website Department of Energy 727-million-barrel underground cache United States Strategic Petroleum Reserve 727-million-barrel underground cache http://energy.gov/fe/services/petroleum-reserves 727-million-barrel underground cache United States Strategic Petroleum Reserve Fossil Energy's Petroleum Reserves Website 727-million-barrel underground cache 727-million-barrel underground cache 727-million-barrel underground cache Petroleum Reserves 727-million-barrel underground cache US Strategic Petroleum Reserve 727-million-barrel underground cache Strategic Petroleum Reserve (SPR) Strategic Petroleum Reserve Department of Energy Site information U.S. Strategic Petroleum Reserve 727-million-barrel underground cache SPR Strategic Petroleum Reserve 727-million-barrel underground cache 727-million-barrel underground cache 727-million-barrel underground cache more than 700 million barrels Strategic Petroleum Reserve (SPR) "Office of Petroleum Reserves" maintains 727-million-barrel underground cache