Drift scale test status report (Chapters 1-9)

Abstract

The Drift-Scale Test (DST) is one of the thermal tests being conducted in the Exploratory Studies Facility (ESF) at Yucca Mountain, Nevada, site of the potential repository for high-level nuclear waste. One of the DST`s major objectives is to study the coupled thermal-hydrologic-chemical-mechanical (THCM) processes at the potential repository`s horizon. The objectives, test design, and test layouts of the DST are included in a previous test design report. this report present results and analysis of several difference measurements made in the DST by researchers at Lawrence Livermore National Laboratory through the second quarter of the heating phase. Sections 1.1 and 1.2 describe the layout of the DST and the boreholes and instrumentation used to monitor the THCM processes in the rock of associated drifts. Section 2 presents an analysis of temperature data for the test through the end of May 1998. Sections 3 and 4 present results of electrical resistance tomography and neutron logging measurements, respectively. These two sets of measurements are designed to determine the movement of moisture in the test. Results of a series of geochemical measurements made on gas and water samples are presented in Section 5. The purpose of these measurements is to monitor the chemical processes occurring in the DST. Section 6 presents results of thermohydrologic modeling analysis of the test, and Section 7 presents data collected via the laboratory testing for characterization of the hydrologic properties of the rock forming the DST. A brief analysis of barometric pressure and humidity data collected through the end of May 1998 is discussed in Section 8, along with temperature data for the bulkhead. Finally, Section 9 presented an evaluation of sensors used in the DST.