PLANS of the American government to safeguard highly radioactive nuclear
waste for thousands of years are unrealistic, according to a report by the
National Academy of Sciences.
The Department of Energy (DOE) has selected Yucca Mountain in the Nevada
desert as a leading candidate for an underground repository for high-level
waste. But the government has tied itself in knots with laws that demand
exact predictions of geological processes and architectural designs that
are guaranteed not to fail.
Scientists, say the report, cannot foresee earthquakes or volcanic activity
that might cause waste to spread. Such predictions, they argue, ‘stretch
the limits of our understanding of geology, groundwater chemistry and movement.
. . .’.
The DOE recently postponed the date for opening the Yucca repository
from 2003 to 2010 because their design could not satisfy all the geological
and legal requirements of a 1982 nuclear waste law.
In the meantime, highly radioactive waste is accumulating at surface
sites in the US, and will reach 30 billion curies by 2000. The report recommends
the government should go ahead and make the waste safe, and that engineers
look for designs using off-the-shelf technology rather than opting for untried
The DOE, which requested the study from the academy, welcomes these
conclusions. The state of Nevada, where Yucca Mountain is located, does
not. Robert Loux, head of the nuclear waste project office for Nevada, accuses
the department of ‘taking the back door’ to get the government to relax
Geologists at the University of New Mexico and at the Yucca Mountain
Project Office in Las Vegas have produced new estimates, suggesting that
volcanic activity occurred just 20 kilometres from the proposed burial site
for high-level radioactive waste as recently as 20 000 years ago. Previous
studies indicated that several volcanic cones in the region last erupted
around 250 000 years ago.