Virginia Focus: Secret Nuclear Studies
U.Va. physicist's work languished Shift in research left school in the lurch
http://www.timesdispatch.com/vametro/MGB88QM5MJC.html
BY CARLOS SANTOS
TIMES-DISPATCH STAFF WRITER Feb 25, 2001

CHARLOTTESVILLE The details are mostly secret. The project is mostly forgotten. But for about 40 years, University of Virginia scientists tinkered with uranium up on Observatory Hill, spinning the gas form of the radioactive material at unimaginable speeds in a huge centrifuge that could shake the building.

Their mission, at the behest of the federal government in the middle of the coldest part of the Cold War, was to make enriched uranium cheaper and faster than the other guys.

Even today, some of the details are classified, though an Energy Department missive sent out last month identified hundreds of sites in the country that did nuclear weapons work during the Cold War in a step toward identifying those workers who might qualify for compensation if they were made ill by their jobs.

On the government's list was U.Va., though the school's groundbreaking work, which ended abruptly in 1985, was focused on developing enriched uranium for nuclear fuel, not for nuclear weapons, according to those involved.

"At that time, during the Cold War, nobody was going to give away ways to provide nuclear power to other countries," said Gerald Fisher, a U.Va. research scientist in charge of security for the project.

But Ralph Lowry, a retired professor in the U.Va. engineering school who ran the project for years, said the top-secret aspect of the work was required because "any enriched uranium, if enriched enough, could be used for nuclear weapons."

Few outside the engineering school knew the details of how, in the small building overlooking the campus, scientists were tinkering with separating uranium isotopes using a gas centrifuge process developed by the legendary U.Va. physicist Jesse W. Beams. Beams, who died in 1977, actually began working on the centrifuge process before World War II - even before the Manhattan project.

"It was not very open. Only a handful of people really knew" about the project, said Ralph Allen, the director of environmental health and safety at the school. "I had clearance to go up there, and I saw parts of it. But it didn't mean much to me."

Ed Spenceley worked as a machinist at the building throughout the project. "I couldn't tell anybody what we were doing," he said. "Not even my wife.'

Fisher said 24-hour-a-day security was provided at the plant and it could take up to a year to get security clearance.

Fisher said some scholarly publications on the project were published, "but with certain portions of information deleted."

During the Manhattan Project, Beams' early work on the centrifuge process was one of two methods under scrutiny to separate uranium's fissionable isotope from natural uranium.

The other method of enriching uranium was the gas diffusion process, which involved pumping uranium hexafluoride gas through thousands of membranelike barriers which trap the heavier isotopes of uranium called U-238. The lighter isotopes, called U-235, passed through. The U-235 was fissionable.

The centrifuge method essentially took uranium hexafluoride gas and spun the gas in a cylinder to bring the lighter isotopes to the top and settle heavier ones in the bottom. The centrifuge spun at incredibly high speeds.

The centrifuge method was not chosen during World War II because its technology was not well-enough developed.

After that decision, the research on the centrifuge method of enriching uranium languished until the 1950s, when U.Va., with money from the federal government, went full bore into developing the gas centrifuge method. The renewed interest came about because the gas-diffusion method, used throughout the country to make enriched uranium, was very power intensive. The development of stronger metals for the centrifuge and work at centrifuges elsewhere in the world also played a part in the project's revival at U.Va.

There was, initially, resistance at the university to the project, said Roland Krauss, who was an engineering professor at U.Va. then and worked on the project.

"The feds came in and waved the flag," he said. "But there was some concern because there would be no diffusion of knowledge."

Even one Austrian scientist who worked for the Nazis during World War II and a German machinist who was awarded the Iron Cross by Hitler worked for a time on the U.Va. project.

"As more nuclear power plants came on, the demand for enriched uranium increased," Lowry said. "We needed a better process and the gas diffusion method used so much power."

The centrifuges evolved and grew in size until one 60 feet in length and several feet in diameter was installed in the building with the help of a 27-foot pit and a raised ceiling. The centrifuge, essentially a hollow metal tube that spun at great speeds, was enclosed. High speed was one of the keys to the separation process. At times, the spinning centrifuge would simply break down, causing what Spenceley called "minor earthquakes in the building."

Lowry said only small amounts of uranium were used in the experiments and special mass spectrometers were used to measure the enrichment. "We were trying to decrease the cost and make it more competitive, to make the machines simpler and more efficient."

The heyday of the gas centrifuge project occurred in the late 1970s, when President Jimmy Carter pushed to build four gas centrifuge plants because the energy consumed would be one-tenth of that used in the gas diffusion process. But the plants never were built in part because of an oversupply of enriched uranium being produced by other countries and because the future of nuclear power plants was already dimming.

The U.Va. project was finally shut down by the federal government in June 1985. The uranium and equipment, including the huge centrifuge, were shipped to the government's nuclear research facility at Oak Ridge, Tenn.

The building is now called the Aerospace Research Lab and all that remains of the centrifuge project are several pits dug for the huge machines. There remains an underground bunker that was formerly used for testing machine guns. The building that remains is used for aerospace research.

Allen said the choice of gas diffusion over the centrifuge process was a blow to the university, which had labored secretly for so many years.

"The school could have become a major nuclear research facility," he said. "It just didn't happen."

Contact Carlos Santos at (804) 295-9542 or csantos@timesdispatch.com