YUCCA MOUNTAIN, Nev. - President Bush picked a 1,200-foot-tall, flat-topped volcanic ridge yesterday as the site to entomb up to 77,000 tons of highly radioactive nuclear waste now piling up at 131 commercial, military and research reactors around the country.
Bush, who announced his decision in a letter to Congress, said, "Proceeding with the repository program is necessary to protect public safety, health, and the nation's security because successful completion of this project would isolate in a geologic repository at a remote location highly radioactive materials now scattered throughout the nation."
The desolate site 90 miles northwest of Las Vegas could begin receiving the waste - some of which will remain deadly for more than 10,000 years - as early as 2010. About $4.5 billion has been spent on excavating and testing the site during the past two decades.
Sen. Harry Reid, a Nevada Democrat and the No. 2 ranking senator, anticipating the selection of Yucca Mountain, denounced Bush's action as "a hasty, poor and indefensible decision" when "the science does not yet exist" to ensure that the wastes can be contained for thousands of years.
Critics say that water seeping through the site will erode the metal containers in which the waste will be stored, and that the volcanic rock has multiple fractures that will allow radiation to escape.
Bush called his recommendation of the site "the culmination of two decades of intense scientific scrutiny involving application of an array of scientific and technical disciplines."
"The claims that we haven't studied this enough are a little distorted," said Energy Secretary Spencer Abraham, who recommended selection of the site to Bush in a letter Thursday.
Nevada's governor, Kenny Guinn, a Republican, is expected to formally object to Bush's selection of the site. That action would shift the decision to Congress, which will have 90 days to vote on it. If both houses of Congress approve the plan by a majority vote, the Energy Department will have 90 days to submit a license application to the Nuclear Regulatory Commission.
If the project moves forward, Yucca Mountain will become a $58 billion temple honoring the survival of commercial nuclear power in this country, which is the nation's second-largest source of energy after coal and generates about 2,000 tons of waste a year.
If the plan stalls, Yucca Mountain could become the mausoleum in which the industry is buried.
No new U.S. nuclear plants have been built since the 1979 accident at Three Mile Island. And none is likely to be built until a permanent home is found for the spent fuel.
Congress directed the Energy Department to begin removing the nuclear waste to Yucca Mountain four years ago. But the plan fell behind schedule, and some utilities are suing the government for breaching its obligation. The potential liability of the lawsuits exceeds $50 billion.
The nuclear waste will be stored about 1,000 feet beneath the mountain's surface and 1,000 feet above the water table. Scientists have used an exploratory tunnel to conduct geohydrology studies to determine how water moves through the mountain and to assess the likelihood that it would seep into the area where the nuclear waste would be stored and into the ground water below.
Tests show that if radioactive contaminants escape from the tunnel, it would take about 300 years for them to enter the water table, and about another 1,000 for them to contaminate well water in Armagosa Valley, a community with a population of 1,400, about 20 miles south of Yucca Mountain.
Preventing contamination of the water table is one of the biggest concerns of the scientists working on the project. And one of their biggest headaches is the possibility that water will accumulate inside the repository.
It rains only about seven inches a year here, but the mountain's rock - compacted volcanic ash formed 13 million years ago - has more water than expected.
Scientists originally thought the rock would serve as a natural barrier to prevent the leakage of radioactive materials. But studies have shown that some of the rock is fractured and radioactive contaminants could escape during the thousands of years it will take for the waste to decay to non-threatening levels.
The Energy Department is also studying seven small, inactive volcanoes near Yucca Mountain, but its officials say the odds of any one of them erupting during the next 10,000 years are one in 70 million.
The potential repository sits between two inactive earthquake faults. There has been seismic activity in the area as recently as few years ago, but government geologists are quick to point out that seismic activity causes more damage above ground than below. They do not believe a quake would have an impact on the radioactive materials
The plan now calls for loading the nuclear material into "packages" made of a highly corrosion-resistant, nickel-based metal called Alloy 22, with an inner layer of stainless steel.
The packages would be covered by titanium drip shields. Titanium is extremely strong and corrosion-resistant. It would act as a shield against falling rock and dripping water.
But the nuclear material will give off heat for a time, and studies are being conducted to determine whether water will condense as it eventually cools down. Wetness could cause the metal containers to corrode and create a contamination problem.
On Monday, Bruce Reinert, an Energy Department civil engineer, stood in Alcove 5 deep under the mountain and peered through a small glass window into a room where the temperature was heated to 400 degrees on Dec. 31, 1997, and held there until Jan. 14 of this year. Highly sophisticated scientific instruments are monitoring the movement of water as the area cools.
"We're committed to telling the public what we think will happen over 10,000 years," he said. "I have faith that as we go further into the project, we will keep making changes and improving it. And maybe in 300 years, we'll have this great thing and pull all the waste out and take care of it, then we'll make this place a tourist attraction."
Robert R. Loux, the executive director the Nevada Agency for Nuclear Projects, a state agency that monitors Yucca Mountain, said federal law dictates that the mountain itself, not the special containers, has to be the primary barrier for the repository.
"The National Academy of Sciences and other scientific bodies have said we cannot rely on the manmade materials more than the next 1,000 years," he said. "After that, the geology has to be the primary barrier because that's the only thing we can count on to provide this long-term isolation.
"So on a legal, regulatory or even a scientific perspective, what's going on at Yucca Mountain does not comply with the law."
Loux said the Energy Department's plan to use titanium drip shields underscores the futility of the project.: "We've hired some of the leading corrosion people in the world, and they say Yucca Mountain is an oxidizing, reducing environment underground and no metal is going to last more than about 1,200 years, not Alloy 22, not titanium, not anything else.
"The Energy Department has announced that Yucca Mountain is the greatest site since sliced bread, and once they got out there, they've found what we told them all along - it's a poor site."
Since 1957, when the Shippingport Atomic Power Station pumped out the nation's first nuclear kilowatt, scientists have been trying to figure out how to safely get rid of the waste created by nuclear fission.
There have been proposals to bury the stuff in polar ice, to blast it into outer space on rockets, to put it under the ocean floor, to stick it on remote islands and to dump it in holes about six miles deep. All of these ideas were dismissed for being scientifically unsound, and federal officials finally turned to Yucca Mountain.
In September 1994, a $13 million machine - a behemoth as long as a football field with a 25-foot-wide cutter head - began boring a tunnel on the north side of the mountain. For three years, the machine's cutting head, with its 48 cutter discs, ground its way through rock and dirt and created a five-mile tunnel through the mountain.
The entire project calls for carving 100 miles of tunnels inside the mountain to create areas to store the nuclear waste.
Sun staff writer David L. Greene contributed to this article.