The Yucca Mountain Nuclear Repository Yucca Mountain is the Department of Energy's (DOE) potential geological repository designed to accept spent nuclear fuel and high-level radioactive waste. If approved, the site would be the nation's first geological repository for permanent disposal of this type of radioactive waste. It is located in Nye County, Nevada, about 100 miles northwest of Las Vegas on federally owned land on the western edge of the Department of Energy's Nevada Test Site. If approved, the repository will be built approximately 1000 feet below the top of the mountain and 1000 feet above the ground water. Scientist, supporters and opponen