Open AccessPreliminary development of the LBL/USGS three-dimensional site-scale model of Yucca Mountain, Nevada
Author(s) -
C.S. Wittwer,
G. Chen,
G.S. Bodvarsson,
Michael P. Chornack,
Alan L. Flint,
Lorraine E. Flint,
Edward Kwicklis,
R.W. Spengler
Publication year - 1995
Language(s) - English
Resource type - Reports
DOI - 10.2172/106718
Subject(s) - geology , hydrogeology , vadose zone , infiltration (hvac) , canyon , grid , geomorphology , hydrology (agriculture) , geotechnical engineering , groundwater , meteorology , geodesy , geography
A 3-D model of moisture flow within the unsaturated zone at Yucca Mountain is being developed at LBL in cooperation with USGS. This site-scale model covers an area of about 34 km{sup 2} and is bounded by major faults to the north, east, and west. The relatively coarse-grid model includes about 300 horizontal grid-blocks and 17 layers. Contour maps and isopach maps are presented defining different types of infiltration zones, and the spatial distribution of Tiva Canyon, Paintbrush, and Topopah Spring hydrogeological units. Matrix flow is approximated using the van Genuchten model, and the equivalent continuum approximation is used to account for fracture flow in the welded units. One-, two-, and three-dimensional simulations are conducted using the TOUGH2 computer program. Steady-state simulations are performed with various uniform and nonuniform infiltration rates; results are interpreted in terms of effect of fault characteristics on moisture flow distribution, and on the location and formation of preferential pathways