The DOE reported there is uncertainty about the underlying resource base in ANWR. "The USGS oil resource estimates are based largely on the oil productivity of geologic formations that exist in the neighboring State lands and which continue into ANWR. Consequently, there is considerable uncertainty regarding both the size and quality of the oil resources that exist in ANWR. Thus, the potential ultimate oil recovery and potential yearly production are highly uncertain."  A considerable source for the uncertainty is due to the fact that the Department of Energy-based these estimates of technically recoverable oil on extremely low price per barrel figures ranging from $12 to $24 per barrel, which has not been seen in a long time.