The SREX process, which was developed at Argonne National Laboratories, has been evaluated for its effectiveness for the decontamination of radioactive liquid waste at the Idaho Chemical Processing Plant located at the Idaho National Engineering Laboratory. The extraction solvent consists of 0.15 M 4’,4’,(5’)-di-(t-butyl-dicyclohexo)-18-crown-6 in either 1.2 (M) under bar TBP/Isopar L(R). Suppressed extraction due to matrix interferences limits D-Sr values to the range of 3-4 in batch extraction experiments. The SREX solvent has been shown to be effective in the removal of non-radioactive Pb from liquid wastes, in addition to the extraction of Sr-90. The information from this study has been used to develop a proposed flowsheet for the treatment of liquid waste in centrifugal contactors.