A Year in the Life of a Nuclear Storage Facility De-Inventory: How Y-12 National Security Complex Successfully Relocated the Inventory of Enriched Uranium Not Qualified for the Highly Enriched Uranium Materials Facility

For many at Y-12 National Security Complex (Y-12), the primary focus last year was the de- inventory of a 65-year-old warehouse containing legacy enriched uranium items ineligible for storage in the newly constructed Highly Enriched Uranium Materials Facility (HEUMF). The load-out had been accelerated from 9 months to 90 days, saving Y-12 an estimated $25 million but requiring a well-orchestrated plan to empty the facility of all items to be excluded from HEUMF before onset of the load-out phase. The entire warehouse inventory had been researched and categorized in preparation for the HEUMF load-out, and all items were evaluated for proper disposition. Hundreds of items, some decades old, some merely in unsuitable containers or in forms unapproved for the new facility (referred to as cats and dogs), did not meet the safety basis criteria for transfer to HEUMF. They required either relocation to another storage facility within Y-12 to be physically exhausted through processing or shipment off-site before the opening of HEUMF in early 2010. Many of the activities required to move the ineligible items were completed within the last year while the old warehouse still had sufficient staffing to execute the moves and to ensure the 90-day accelerated load-out was not impacted. This paper discusses the major activities, surprises, lessons learned, and notable events encountered while working through the materials during this successful, although often stressful and never dull, de-inventory period.