The principal objective of the Underground Storage Tank Integrated Demonstration (UST-ID) Program is the demonstration and continued development of technologies suitable for the remediation of USTs. The most promising new technologies are selected for demonstration, testing, and evaluation. The objective is the eventual transfer of new technologies as a system to full-scale remediation at US Department of Energy (DOE) complexes and sites in the private sector. Technologies under development in the UST-ID Program are targeted toward use in remediation actions at the following five DOE participant sites: Hanford, Fernald, Idaho, Oak Ridge, and Savannah River. Combined, these participant sites have more than 300 USTs containing more than 100 m gal of high-level and low-level radioactive liquid waste. This paper focuses on the Waste Separations and Pretreatment area of the UST-ID, summarizing the currently funded technology development projects. In this area, several ''compact processing units'' (CPUs) are being developed to effect near-term demonstration and deployment of promising processes in actual tank environments. The CPU design and development approach is summarized. A number of programmatic issues are discussed, including onsite and offsite transportation of potentially contaminated processing systems, containment design criteria, including applicable codes and standards, and operation and maintenance of such systems in a developmental testing environment.