“…UF 6 solid, at room temperature, has been found in laboratory-scale experiments to be potentially resistant to water dissolution under certain conditions. 75 In particular, if the UF 6 and water are at room temperature, the UF 6 is in a monolithic mass, and the upper surface of the UF 6 is horizontal, an interface layer of reactant forms at the UF 6 -water interface which can effectively prevent gross dissolution. Also, if a cylinder containing UF 6 is submerged with some small aperture (such as a open valve or other similarly small penetration through the containment wall), reactants may plug the opening and inhibit extensive dissolution.…”