Sand Reactor

Abstract

In the mid-1990s, discussions began regarding the possibility of achieving super-criticality in underground plutonium repositories. These discussions were initiated by the work of Charles Bowman from Los Alamos National Laboratory. Theoretically, achieving such an effect is possible. Spent fuel in underground repositories can be washed away by groundwater, and then the plutonium can become concentrated in an underground lens after forming an ore body. In such a system, the efficiency co-efficient [K_cff] has a maximum when there is a specific correlation of hydrogen and plutonium nuclei. Consequently, the system could become supercritical either with an increase in the proportion of water or, conversely, with a decrease in that proportion. A pulsing reactor could be formed, as occurred at Oklo (Gabon), or, in an extreme case, a thermal explosion (or a series of explosions) that destroys the ore body could take place.