Saturated-zone hydrology has presented challenges to USGS researchers at Yucca Mountain. Technical challenges include deep (>700 meters or 2,000 feet) water levels, flow through fractured volcanic rocks, perched water bodies, large hydraulic gradients, the influence of structural features on ground-water flow, and earthquake-induced water-level fluctuations.

USGS monitored water levels in Tertiary volcanic rocks, and in Paleozoic carbonate rocks at one site, at Yucca Mountain from 1985 through 1999. The water-level data have been used to construct potentiometric-surface maps of the Yucca Mountain area and in the construction and calibration of ground-water flow models. Since 1999, water levels have been monitored by the University of Nevada Las Vegas.

C-Hole Complex

The C-hole complex is a group of 3 boreholes (UE-25 c#1, UE-25 c#2, and UE-25 c#3) located just east of Yucca Mountain. The boreholes were drilled in order to conduct multiple-well aquifer and tracer tests that would provide data needed to support ground-water flow and transport models for site characterization.

Alluvial Testing Complex (ATC)

The Alluvial Testing Complex (ATC) project is a cooperative study by USGS, DOE, Nye County, Los Alamos National Laboratory, and University of Nevada Las Vegas to test the hydraulic and transport characteristics of the thick, saturated alluvium south of Yucca Mountain.

Computer Modeling

Modeling is an integral part of DOE’s site-characterization and performance-assessment strategies. The USGS constructed some of the early (2D) ground-water flow models of the site, 3D hydrogeologic framework models at both the site and regional scale, fracture-network models, and 3D ground-water flow models of the entire Death Valley region.

Water Related Studies in the Nevada District

U.S. Department of the Interior U.S. Geological Survey
URL: http://www.usgs.gov/default.asp
Page Contact Information: USGS Web
Page Last Modified: