Thermal expansion, thermal conductivity, and heat capacity measurements at Yucca Mountain, Nevada

Abstract A very extensive database for thermal properties of Yucca Mountain tuffs has been collected to characterize the Yucca Mountain, NV site. Cores from boreholes UE25 NRG-4, UE25 NRG-5, USW NRG-6, and USW NRG-7/7A, all drilled near the North Ramp of the Exploratory Studies Facility, were tested to determine thermal conductivity, thermal expansion, and specific heat. Specimens were tested from four thermal-mechanical units (TCw, PTn, TSw1, and TSw2) that included welded devitrified (TCw, TSw1, TSw2) and nonwelded vitric (PTn) tuff. The effects of moisture content, temperature, and composition were assessed. Petrologic data were obtained from 97 samples, all from USW NRG-6, to assess relationships between measured thermal properties and composition.