Simulated potentiometric surface contours of prepumping conditions in layer 16 of the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and California

These simulated potentiometric surface contours represent prepumping (or steady-state) conditions for model
layer 16 of the Death Valley regional ground-water flow system (DVRFS), an approximately 45,000 square-
kilometer region of southern Nevada and California. The numerical ground-water flow model simulates
prepumping conditions before 1913 and transient-flow conditions from 1913 to 1998 after pumping of ground
water began. The DVRFS transient ground-water flow model is the most recent in a number of regional-scale
models developed by the U.S. Geological Survey (USGS) for the U.S. Department of Energy (DOE) to
support investigations at the Nevada Test Site (NTS) and at Yucca Mountain, Nevada (see "Larger Work
Citation", Chapter A, page 8, for details).