Bechtel, in partnership with Science Applications International Corp., has begun work on the management and operating contract for the civilian radioactive waste management program for the U.S. Department of Energy. The $3.1 billion, five-year contract supports DOE's efforts to design, construct, and operate a permanent geologic repository to safely store the nation's spent nuclear fuel and other high-level radioactive waste at Yucca Mountain, nearly 100 miles northwest of Las Vegas.