Instrumentation Reliability Study for Future Waste Repository Sites

In evaluating the reliability of instruments for waste repository applications, we found geotechnical instruments to be the least reliable. Geotechnical instruments measure the engineering aspects of geology, geophysics, and hydrology. Systems were designed with off-the-shelf instrumentation which was designed for short-term, ambient temperature measurements. Reliability problems developed when these off-the-shelf instruments were used in long-term high-temperature DOE experiments. The Stripa, Climax, and Avery Island DOE experiments had identical instrumentation failures with this off-the-shelf design approach. The DOE experimenters, working with instrument manufacturers, have been successful in obtaining more reliable instruments. However, issues must still be addressed if high reliability is to be achieved at future high-level waste repository sites.