A FRUIT OF YUCCA MOUNTAIN: THE REMOTE WASTE PACKAGE CLOSURE SYSTEM

摘要

Was the death of the Yucca Mountain repository the fate of a technical lemon or a political lemon? We must be careful not to let this debate lure us away from capitalizing on the fruits of the project. One such fruit is a system for safely sealing packages containing radioactive nuclear waste. In March 2009, Idaho National Laboratory (INL) successfully demonstrated the Waste Package Closure System (WPCS), a full-scale prototype system for closing waste packages (WPs) that were to be entombed in the now-abandoned Yucca Mountain repository. This paper describes the system and components, which INL designed and built, to weld the closure lids on the WPs, nondestructively examine the welds using four different techniques, repair the welds if necessary, mitigate crack-initiating stresses in the surfaces of the welds, evacuate and backfill the WPs with an inert gas, and perform all of these tasks remotely. As a nation, we now have a proven method for securely sealing nuclear WPs for long-term storage-regardless of whether the future destination for these WPs will be an underground repository. Additionally, many of the WPCS'sfeatures and concepts may benefit other remote nuclear applications.