The federal government got mixed news this month about its efforts to safely stow the nation's nuclear waste. Department of Energy (DOE) officials were pleased on 22 March when a federal judge waved aside a final lawsuit aiming to block the first shipment of radioactive waste to its Waste Isolation Pilot Plant (WIPP), a series of excavated salt caverns near Carlsbad, New Mexico (Science, 12 March, p. 1626). After a 25-year struggle, WIPP expects this week to off-load the first trucks filled with tainted clothing, tools, and nuclear weapons leftovers.
Another long-planned repository, however, faces more questions. On 3 March, a technical review board raised further doubts about the adequacy of plans for a repository under Yucca Mountain, Nevada, where Congress wants to stash the bulk of the nation's hottest stuff, such as commercial power plant wastes. (Science, 12 March, p. 1627). The U.S. Nuclear Waste Technical Review Board asked DOE to reconsider current plans that allow waste to generate high temperatures in the vault. Instead, it wants the agency to ponder designs for keeping lower temperature waste caskets, which have less chance of boiling groundwater and geochemically altering surrounding rock.