Energy Secretary Samuel Bodman Aug. 15 ordered construction to resume after nearly three years on the $12-billion nuclear waste-treatment plant being built by Bechtel National at the Hanford Site in Washington state, after certifying that the plant's design was revamped to reflect the seismic data that engineers have been collecting for more than two years.

In December 2004, DOE halted construction on some parts of the vitrification facility over concerns that it was not designed adequately to withstand the effects of a powerful earthquake. James Rispoli, DOE's assistant secretary for environmental management, said confirming the seismic data has been one of DOE's top priorities and toughest technical challenges.

DOE can now move forward with "one of the largest and most complex nuclear facilities in the DOE," Rispoli said. DOE is building the Hanford plant to "vitrify," or stabilize in glass-like logs, some 53 million gallons of high-level radioactive waste that threatens to contaminate the nearby Columbia River.

DOE ordered Bechtel to stop laying structural concrete at parts of the facility after scientists released preliminary results of a sophisticated earthquake study. Last year, DOE launched a major initiative to study the seismic characteristics of the site and to incorporate the findings into the design of the plant. Among other things, scientists analyzed samples that were taken from 1,400-foot-deep boreholes that were drilled near the plant.

Congress has generally backed DOE's efforts to build the plant, noting that the facility is vital to cleaning up the contaminated Hanford site.

But some lawmakers have faulted DOE for ignoring warnings of earthquake-related problems with the plant that were articulated as early as 2002.