TCS Daily


Modern Alchemy

By Herbert Inhaber - January 27, 2003 12:00 AM

Years ago, on a visit to Prague, now in the Czech Republic, I visited Hradcany Castle. It was like many other European castles, with one difference: it had some rooms devoted to the medieval science of alchemy - transforming one element to another.

The alchemists of the Middle Ages, forerunners of modern chemists, tried to change lead into gold, for obvious reasons. There wasn't much of a market for turning lead into copper.

I was reminded of this when reading about the Department of Energy's Accelerator Transmutation of Waste (ATW) program. The problem it tried to solve is well-known. Used-up fuel rods from nuclear reactors are slated to be sent to the Yucca Mountain site, near Las Vegas, over the next few decades. Living in Sin City myself, I have followed the political battles closely. President Bush signed the bill to start the shipments last summer, although the State of Nevada is still pursuing the matter in court.

The goal of ATW is reduce the waste, now estimating at 77,000 metric tons, by a factor of 100. It would do this by an elaborate system of chemical separation of the elements in the fuel rods, and then bombardment by particles from accelerators to transform at least some of the highly radiaoactive elements into non-radioactive ones.

First, a word about politics. It is difficult to find a decision about energy, except perhaps in searching for sub-atomic quarks, that is not affected by political considerations.

Modern transmutation has been around for over a century, ever since the experiments by Lord Rutherford and others in Canada and Britain. It was regarded as a scientific curiosity, since only a few atoms at a time could be transmuted. This changed with the advent of nuclear fission, where uranium could be transmuted into plutonium and other elements on a large scale.

A few decades ago, nuclear experts realized that transmutation was another way to handle spent fuel rods. Little was done until the controversy over Yucca Mountain heated up. Democratic Senator Harry Reid of Nevada, the former majority whip, saw this as an alternative to shipping wastes to Yucca Mountain. Instead of 77,000 tons, there might be 770 tons of waste. And where to put that small amount? Not in Nevada, of course.

Ordinarily the Republicans would be opposed to such a massive expenditure, especially when the government had spent billions on Yucca Mountain already. But Sen. Pete Domenici of New Mexico was head of the Senate Budget Committee. His state happens to house Los Alamos National Laboratory, which just happened to be the headquarters of the then - small ATW program. Washington observers, in about a microsecond, could figure out what would happen next.

The Department of Energy clearly didn't want a new program to deal with nuclear wastes, since they had put all their eggs in the basket of Yucca Mountain. But Reid and Domenici were able to attach funding to a massive appropriations bill, an all-too-common event in the Beltway.

The politics goes back far beyond the two Senators' maneuvering. Scientists know that if you want to transmute the radioactive elements in spent fuel, the most efficient way is in a specially designed nuclear reactor. But this was anathema to the Clinton administration. So they came up with a scheme to bombard the wastes with protons - sub-atomic particles - from an accelerator. Large accelerators have been used for advanced physics research, but never for the massive production envisioned by the ATW program.

Will ATW work? As John Zink, the editor of Power Engineering, wrote in January 2002, "engineers must design chemical separation technologies capable of recovering more than 99.9 percent of the plutonium and uranium and more than 99 percent of the major actinides (other radioactive elements) in the spent fuel". This will prove an extremely difficult and expensive task.

The American Nuclear Society, probably the best collection of experts on the subject, noted that no new science will be needed for the project. That is, the nuclear reactions envisioned for ATW are already in the textbooks. But they pointed out that the overall cost of the project, of the order of $280 billion, far dwarfs the already gigantic total of about $30 billion to be spent on Yucca Mountain. And even if ATW solved all of its problems and came in at a low price, there would still be the problem of finding a place for the small amount of radioactive waste left over. It took 20 years for final Congressional approval of Yucca Mountain. Do we want to start the process all over again?

A final note: The spent fuel that is supposed to be heading for Yucca Mountain is not "nuclear garbage", as some have claimed. Reprocessing the elements in the fuel and using them in reactors could supply electricity for centuries to come. Some have calculated that the value of the stored energy in the fuel rods outstrips the worth of all the oil in Saudi Arabia. That is why Yucca Mountain will not be sealed for a century, or perhaps never - we may want to get the fuel rods out of the ground at some point. Accelerator transmutation of waste would destroy the chance of that ever happening.
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