Publications
Determination of the Porosity Surfaces of the Disposal Room Containing Various Waste Inventories for WIPP PA
Park, Byoung P.; Hansen, Francis D.
This report develops a series of porosity surfaces for the Waste Isolation Pilot Plant. The concept of a porosity surface was developed for performance assessment and comprises calculation of room closure as salt creep processes are mitigated by gas generation and back stress created by the waste packages within the rooms. The physical and mechanical characteristics of the waste packaging that has already been disposed--such as the pipe overpack--and new waste packaging--such as the advanced mixed waste compaction--are appreciably different than the waste form upon which the original compliance was based and approved. This report provides structural analyses of room closure with various waste inventories. All of the underlying assumptions pertaining to the original compliance certification including the same finite element code are implemented; only the material parameters describing the more robust waste packages are changed from the certified baseline. As modeled, the more rigid waste tends to hold open the rooms and create relatively more void space in the underground than identical calculations run on the standard waste packages, which underpin the compliance certification. The several porosity surfaces quantified within this report provide possible ranges of pressure and porosity for performance assessment analyses.3 Intentionally blank4 AcknowledgementsThis research is funded by WIPP programs administered by the U.S. Department of Energy. The authors would like to acknowledge the valuable contributions to this work provided by others. Dr. Joshua S. Stein helped explain the hand off between these finite element porosity surfaces and implementation in the performance calculations. Dr. Leo L. Van Sambeek of RESPEC Inc. helped us understand the concepts of room closure under the circumstances created by a rigid waste inventory. Dr. T. William Thompson and Tom W. Pfeifle provided technical review and Mario J. Chavez provided a Quality Assurance review. The paper has been improved by these individuals.Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94Al850005 Intentionally Blank6