The Los Alamos National Laboratory (LANL) Tritium Systems Test Assembly (TSTA) project was begun in 1978 to develop, design, and demonstrate the technology and safe operation of selected tritium processing systems required for a fusion reactor. In 2001, the US Department of Energy (DOE) determined that TSTA's mission was complete and that the facility should be stabilized.

At the completion of the stabilization project in 2003, TSTA was categorized as a radiological facility. Before stabilization was complete, the tritium inventory at TSTA was grouped in the following categories: tritium gas mixed with hydrogen isotopes, tritiated water absorbed on molecular sieve, tritium held up as a hydride on various metals, and tritium held up in process components. For each of these, tritium content was characterized, a path for removal was determined, and the proper disposal package was developed. Hydrogen exchange, calorimetry, direct sampling, pressure/composition/temperature, radiological smear surveys, and controlled regeneration were used to determine the tritium inventory for each category of tritium.

After removal, the tritium inventory was either (1) sent to other facilities for reuse processing or (2) buried at the LANL radioactive waste disposal site. One complete experimental system was packaged and transferred to another DOE site for future use. Special burial containers were designed and fabricated for the inventory buried at the LANL radioactive waste disposal site. The project was conducted with low tritium emission to the environment and negligible personnel exposure. After the tritium removal was complete, all remaining hardware and piping were opened and vented; the facility emission was below 1 Ci per day.