Measuring and Modeling Water Imbibition into Tuff

摘要: Yucca Mountain (Nevada) is being investigated as a potential site for high-level-radioactive-waste repository. The combines partially saturated hydrologic system and stratigraphy of fractured, welded nonwelded tuffs. long time scale phenomena makes their direct measurement prohibitive. Also, modeling difficult because the tuffs exhibit widely varying, often highly nonlinear properties. To increase basic understanding both properties flow in regimes, following tasks were performed, results are reported: (1) Laboratory Experiment: Water imbibition into cylinder tuff (taken from drill core) was measured by immersing one end dry sample water noting its weight at various times. approximately one-dimensional, filling bottom to top. (2) Computer Simulation: experiment modeled using TOSPAC (a finite-difference computer program simulating saturated, layered media) with data currently considered use site-scale repository Mountain. measurements compared. Conclusions drawn respect accuracy transientmore » porous medium one-dimensional model available hydrologic-property data.« less