Finsterle and Trautz (2000): Numerical Modeling of Seepage into Underground Openings

Numerical Modeling of Seepage into Underground Openings

Stefan Finsterle and Robert C. Trautz

Society for Mining, Metallurgy and Exploration
Annual Meeting and Exhibit
Salt Lake City, Utah
February 28 – March 1, 2000

Lawrence Berkeley National Laboratory, Earth Sciences Division
University of California, Berkeley, CA 94720

Abstract. We performed numerical modeling studies to investigate water seepage into underground openings excavated from unsaturated fractured formations. Water seepage is a key factor which would affect the performance of a nuclear waste repository at Yucca Mountain if one is built at the site. The amount of water dripping into an underground opening depends on the connectivity and permeability of the fracture network as well as on the capillarity of individual fractures intersecting the opening. We developed a high-resolution numerical model of an unsaturated fracture network and examined the appropriateness of seepage predictions using a fracture continuum model. Model calibrations to liquid-release tests performed at Yucca Mountain are also discussed.