Year
2000
Abstract
Since its initiation, the Ambient Field Testing Program at Yucca Mountain has been providing critical data necessary for input to the final Total Systems Performance Assessment that is required as part of the licensing process to assess Yucca Mountain as a potential High Level Nuclear Waste Repository site. Currently, the major project emphasis is on those ambient field testing activities relating to the first revision of the Site Recommendation Report which will eventually indicate the suitability or unsuitability of Yucca Mountain as a potential High Level Radioactive Waste Repository. Within the Exploratory Studies Facility (ESF) tunnel, the Upper Tiva Canyon Alcove (Alcove 1), Upper Paintbrush (non-welded) Contact Alcove (Alcove 3), Cross-Over Alcove, and all of the Drift-Scale Moisture Seepage Niches, Percolation and seepage testing is being conducted. This testing quantifies seepage from a localized moisture population event of short duration into an underground opening. Thermal Testing, which measures the changes of rock saturation and thermal expansion, before, during, and after heating, continues in the Thermal Testing Facility. The Large Scale Unsaturated Zone (UZ) test, which investigates the unsaturated flow and transport properties of tuff underlying the potential repository horizon, continues at Busted Butte, adjacent to Yucca Mountain, in support of ongoing modeling efforts. Mock scale Engineered Barrier System testing which studies the effects of different materials (i.e., crushed tuff, quartz sand, or limestone) and their influence on drip shield performance are also being conducted. The project is currently participating in an Early Warning Drilling Program in association with local state agencies to conduct hydraulic tracer testing (Alluvial Tracer Complex) which will determine the diffusion/mass transfer rates between flowing and non-flowing water in saturated alluvium and will estimate the volumetric drift velocity of the groundwater alluvium near Yucca Mountain. This paper is an overview of the current Ambient Field Testing Program being conducted at Yucca Mountain, and its importance to assessing the performance of Yucca Mountain as a potential High Level Radioactive Waste Repository.