Publications Details
Materials Interface Interactions Test (MIIT) details and observations on in situ sample retrievals and test termination
The Materials Interface Interaction Tests (MIIT) program involves the comparative performance-evaluation testing of multiple US and foreign nuclear waste glasses (nonradioactive), potential canister and overpack metals, brine, and geologic materials in the rock salt repository environment at the Waste Isolation Pilot Plant (WIPP) facility. We emplaced about 2000 materials specimens onto fiftn, separate test assemblies and exposed them to a heated, salt-brine environment at the WIPP for multi-year periods. We successfully terminated the in situ conduct of the MIIT in July 1991, after five years of testing, and retrieved all samples for posttest laboratory analyses. These 5-year glass and metal samples, along with samples previously retrieved after 0.5, 1, and 2 years, are being analyzed in multiple international laboratories, in a cooperative testing effort. Individual test participants will present available laboratory results, and interpretations, on MIIT specimens in this workshop. Our focus in this paper is to summarize technical details and repository-relevant observations on the in situ conduct, sampling, and termination operations of the MIIT experimental program. Such information should be useful for the interpretation of the laboratory-based analyses. This information also will be relevant and instructive for other organizations contemplating, planning, or conducting additional materials-related, in situ tests.