To meet the demands of United States weapons production in the 21st century, the Department of Energy (DOE) Y 12 National Security Complex has made intensive efforts to modernize its Cold War-era facilities to meet today’s more stringent safety and security requirements and reduce its security footprint. DOE called on Tetra Tech to provide vital technical, project, and program support to address a number of nuclear material management tasks at the Y 12 Complex. Some of these tasks included disposition of unneeded legacy classified items occupying costly storage space in many facilities and relocating large quantities of highly enriched uranium (HEU) from multiple Y 12 facilities to the new Y 12 HEU Materials Facility (HEUMF).

Applying Tetra Tech’s unique combination of technical expertise and historical knowledge of United States defense programs and Y 12 facilities and processes, our team performed detailed walk-downs to inventory more than 1 million cubic feet of non-special nuclear material classified items. We developed a lifecycle management plan for the materials and an execution plan for consolidating items to be retained, as well as disposing of unneeded materials. Subsequently, we provided technical and management support, including developing shipping information, for disposition of more than 400,000 cubic feet of unneeded materials.

Tetra Tech also developed and maintained a project execution plan and schedules for relocating HEU materials from multiple Y 12 sites to the HEUMF. Tetra Tech performed data mining and analyzed material forms, containerization, and locations. Our team identified and grouped the materials into four categories: to be stored in the HEUMF as-is, to be re-containerized or processed to meet HEUMF acceptance criteria, to be dispositioned before existing storage facilities were closed, or to be stored temporarily in another area at Y 12. Tetra Tech also developed a Y 12 Transportation Safety Document. The loading of materials into the HEUMF was accomplished on schedule and within budget.

With Tetra Tech management and oversight expertise, Y-12 reduced the number of classified facilities from 26 to 6 and facilities storing HEU from 10 to 3. Through our continuing work with Y 12 materials management, we have provided extensive support to the DOE Nuclear Materials Management Team (NMMT) to address the relocation, consolidation, and disposition of materials throughout the DOE complex.