Book Description

Among the highest priorities for action under the Hanford Federal Facility Agreement and Consent Order (Ecology et al. 1989a), hereafter referred to as the Tri-Party Agreement, is the retrieval, treatment and disposal of Hanford Site tank waste. Tank waste is recognized as one of the primary threats to the Columbia River and one of the most complex technical challenges. Progress has been made in resolving safety issues, characterizing tank waste and past tank leaks, enhancing double-shell tank waste transfer and operations systems, retrieving single-shell tank waste, deploying waste treatment facilities, and planning for the disposal of immobilized waste product. However, limited progress has been made in developing technologies and providing a sound technical basis for tank system closure. To address this limitation the Accelerated Tank Closure Demonstration Project was created to develop information through technology demonstrations in support of waste retrieval and closure decisions. To complete its mission the Accelerated Tank Closure Demonstration Project has adopted performance objectives that include: Protecting human health and the environment; Minimizing/eliminating potential waste releases to the soil and groundwater; Preventing water infiltration into the tank; Maintaining accessibility of surrounding tanks for future closure; Maintaining tank structural integrity; Complying with applicable waste retrieval, disposal, and closure regulations; Maintaining flexibility for final closure options in the future. This paper provides an overview of the Hanford Site tank waste mission with emphasis on the Accelerated Tank Closure Demonstration Project. Included are discussions of single-shell tank waste retrieval and closure challenges, progress made to date, lessons learned, regulatory approach, data acquisition, near-term retrieval opportunities, schedule, and cost.