This digital data set defines the lateral boundary of the area simulated by the steady-state ground-water flow model of the Death Valley regional ground-water flow system (DVRFS) by D'Agnese and others (2002). The DVRFS flow model was 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. The model area is an approximately 45,000 square-kilometer region of southern Nevada and California. The model simulates prepumping conditions of the DVRFS and provides starting conditions for the development and calibration of a transient ground-water flow model, (see "Larger Work Citation", Chapter A, page 8, for details). The lateral boundary encompassing the model domain is a combination of no-flow boundaries resulting from physical barriers or hydraulic separation of flow regimes (ground-water divides and [or] regional flow lines) and arbitrary lateral-flow (throughflow) boundaries where water is allowed to flow across the lateral boundary.