The Wastewater Triad Project (WTP) consists of three operational units: the cesium removal (CsR) system, the out-of-tank evaporator (OTE) system, and the solid/liquid separation (SLS) system. These systems were designed to reduce the volume and radioactivity of low-level liquid waste (LLLW) stored in the Melton Valley Storage Tanks (MVSTs) and are operated independently or in series in order to accomplish the treatment goals. Each is a modular, skid-mounted system that is self-contained, individually shielded, and designed to be decontaminated and removed once the project has been completed. The CsR and OTE systems are installed inside Building 7877; the SLS system is installed adjacent to the east side of the MVST 7830 vault cover. The CsR, which consists of ion-exchange equipment for removing {sup 137}Cs from LLLW, was demonstrated in 1997. During the Cesium Removal Demonstration, 30,853 gal of radioactive supernate was processed and 1142 Ci of {sup 137}Cs was removed from the supernate and loaded onto 70 gal of a crystalline silicotitanate sorbent manufactured by UOP, Inc. The OTE system is a subatmospheric single-stage evaporator system designed to concentrate LLLW to smaller volumes. It was previously demonstrated in 1996 and was operated in 1998 to process about 80,000 gal of …

This report documents the process used by the Tanks Focus Area (TFA) to analyze and develop responses to technology needs submitted by five major U.S. Department of Energy (DOE) sites with radioactive tank waste problems, and the initial results of the analysis. The sites are the Hanford Site, Idaho National Engineering and Environmental Laboratory (INEEL), Oak Ridge Reservation (ORR), Savannah River Site (SRS), and West Valley Demonstration Project (WVDP). During the past year, the TFA established a link with DOE's Fernald site to exchange, on a continuing basis, mutually beneficial technical information and assistance.