<P dir=ltr align=left><SPAN style="FONT-SIZE: 15pt; FONT-FAMILY: Arial; mso-fareast-font-family: SimSun; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: FA"><STRONG>Board member says Energy Department still has to
Board member says Energy Department still has to prove Yucca project safe
<?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />LAS VEGAS — A scientist reviewing plans for a national nuclear waste dump in Nevada said Wednesday the Energy Department still needs to prove the Yucca Mountain project won’t leak radioactivity.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />
“The testing that’s being done has not answered the question we’d like answered,” said Ronald Latanision, a nuclear engineering expert and member of the U.S. Nuclear Waste Technical Review Board studying the Yucca project. “What is the likely stability of the materials over the life of the project?’ ”
He said the Energy Department has not shown that metal casks encasing the nation’s most highly radioactive waste will withstand corrosion while entombed for centuries in tunnels hot enough to roast a turkey.
“We haven’t seen the data. We don’t know it exists,” Latanision said in an interview before a second day of meetings in Las Vegas.
J. Russell Dyer, the top Yucca Mountain official attending the meetings, said Energy Department scientists plan to address concerns that current project designs could let waste containers corrode and leak radioactivity.
“We’ve got some data. We’re acquiring more,” Dyer said, adding that some questions might remain unanswered while the Energy Department applies for a license to operate the Yucca site.
“Some tests are going to go on for a very long time,” he said.
The 11-member board has raised concerns about possible corrosion in a letter and subsequent report to Margaret Chu, the Energy Department’s Yucca Mountain project chief.
Chu dismissed the concerns as premature and promised a full report this year.
Five board members attended the two-day Las Vegas meetings, which were part of a technical subcommittee studying water and geology issues affecting the Yucca project.
Subcommittee Chairman Richard Parizek said Wednesday he believed Energy Department scientists will provide data when the full board meets May 18-19 in Washington, D.C.
At issue is whether the nuclear dump should be designed to entomb casks containing radioactive waste above or below the boiling point.
The Energy Department’s current “hot” design foresees the decay of radioactive isotopes raising the temperature of tunnels 1,000 feet beneath Yucca Mountain to about 320 degrees.
An alternate “cold” design could keep temperatures at about 200 degrees by redesigning canisters or spacing them farther apart or providing more ventilation in the tunnels.
Dyer said the “hot” design will be more cost-effective. He said heat is expected to create a thermal barrier in the rock around the tunnels to boil away water before dissolving salts and other minerals settle on the canisters.
A former board member who has become an outspoken critic of the Yucca Mountain design said in a telephone interview that he was concerned the Energy Department was disregarding safety while pressing to meet a self-imposed deadline to file a license application by the end of the year.
“This is a classic situation where the schedule takes precedence over the science,” said Paul Craig, a University of California-Davis physicist and engineering professor who quit the Nuclear Waste Technical Review Board in January.
He compared the Yucca Mountain project to NASA’s ill-fated Columbia and Challenger space shuttles.
“Having a schedule-driven organization where the science is uncertain is a prescription for disaster,” he said.
The government wants by 2010 to begin moving 77,000 tons of highly radioactive waste from commercial and military sites in 39 states to Yucca Mountain, about 90 miles northwest of Las Vegas.
Latanision, a Massachusetts Institute of Technology materials science and engineering professor, said that during the life of the Yucca project, water and water vapor inevitably will form a briny acid that slowly could eat into the canisters and let radioactivity escape.
Hydrologists presented studies Wednesday that any Yucca Mountain contamination seeping into ground water would flow southwest beneath the desert toward the Amargosa Valley and Death Valley National Park.
Claudia Faust, U.S. Geological Survey hydrologist from San Diego, said the process could take 10,000 years.