In situ formation of U(VI)-Fe(III) oxides and hydroxides can provide effective uranium remediation. The reason for this is that such compounds can effectively sequester uranium, even in the (VI) oxidation state. Such compounds can be formed in situ by 1) providing Fe(II), 2) reducing uranium to U(IV), and 3) oxidizing the resulting mixture to provide the desired U(VI)-Fe(III) oxides and hydroxides.
 This invention was made with Government support under contract number DE-SC0006783 awarded by the Department of Energy. The Government has certain rights in this invention.