Technical position on postclosure seals, barriers, and drainage system in an unsaturated medium

The purpose of this technical position is to provide guidance with respect to the current Department of Energy sealing and drainage concepts for a geologic repository in an unsaturated medium. Section 2.0 of the technical position provides a listing of the 10 CFR 60 regulations which are applicable to the design, testing, selection of materials and placement of the postclosure seals, barriers and drainage system. Staff position statements and the corresponding discussions are presented in Sections 3.0 and 4.0, respectively. Technical positions are organized according to the following topics: (1) design consideration, (2) site characterization considerations, (3) performance confirmation considerations, and (4) performance analysis considerations. 6 refs