Publications
WIPP disposal room closure calculations for various waste inventories
This paper develops a series of room closure and porosity surface calculations, which are used to assess performance of the Waste Isolation Pilot Plant. The concept of a porosity surface comprises calculation of room closure as salt creep is resisted by back stress created by the waste packages and by hypothetical gas generation within the rooms. The physical and mechanical characteristics of some of the waste packaging are appreciably different from the assumed waste upon which the original compliance was based and approved. These analyses provide insight into the structural response of a room full of various wastes, including the influence of the waste in the absence of gas generation, as well as the lack of influence on room closure when gas generation is modeled. 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, 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. Several porosity surfaces were developed to cover a range of possible packaging. Copyright 2006, ARMA, American Rock Mechanics Association.