by Bruce Molholt

Today, nuclear power is being heavily touted as an answer to global warming, not only by the nuclear industry but by some political candidates, most notably John McCain, who advocates building 100 nuclear plants in the U.S., 45 in the next 22 years.

It's been nearly 30 years since the accident at Three Mile Island, just south of Harrisburg, which essentially killed nuclear power development in the U.S. No new plants have been planned or built in the U.S. since the March 1979 accident.

Although the accident was less severe than the Chernobyl disaster in 1986, an estimated 95 percent of the reactor core melted and containment was breached within an inch of the infamous "China syndrome." This catastrophe occurs when molten uranium fuel and a myriad of radioactive byproducts leak into groundwater and release highly radioactive steam into the air for hundreds of miles around, depending on wind speed and direction.

It's true that, unlike coal or natural-gas fired plants, nuclear reactors don't emit carbon dioxide -- a major contributor to global warming. But nuclear power is still hardly "clean." There has been a dismal failure of the industry and government to solve the dirtiest aspect of nuclear power -- the production of 30 tons of highly radioactive wastes per year for each reactor.

Over the years, the U.S. has tried to deal with highly toxic radioactive wastes in spent fuel in several different ways: Spent fuel reprocessing, long-term disposal of spent fuel at Yucca Mountain, Nev., and long-term storage of spent fuel on-site.

Each method has proven untenable and portends potential widescale health hazards even with the present U.S. total of 104 nuclear plants, let alone Sen. McCain's proposal to essentially double that number.

We tried spent fuel reprocessing at West Valley, N.Y., south of Buffalo, in 1966-72. During that six years, the plant reprocessed only a year's worth of spent nuclear fuel from 21 reactors.

It is now permanently closed due to poor performance, environmental contamination and exposure of workers to dangerously high levels of radiation. The environmental cleanup tab alone has reached $5 billion.

In 1982, Congress approved a national spent-fuel repository at Yucca Mountain, 100 miles northwest of Las Vegas. Now, 26 years and $60 billion later, DOE estimates that this long-term repository may begin accepting an estimated 70,000 tons of spent fuel within the next 20 years or so. In the meantime, the nation's 104 nuclear plants will continue to store spent fuel on-site.

While on-site storage of spent fuel was meant to be a temporary fix, closure of West Valley and delays at Yucca Mountain have forced the industry to adopt longer-term measures. The annual nuclear waste at each reactor is 30 tons. Initially, these wastes were put into pools of water on-site.

Adequate space was allotted between the fuel assemblies and the radioactive water is circulated to keep the assemblies from overheating. But as the pools became more crowded, the risks increased. About a decade ago, the pools became so crammed that the industry began using dry-cask storage.

There are two types of dry casks for on-site storage of spent nuclear fuel -- above  and below ground. These stainless-steel casks are hot and are cooled via natural air circulation (above-ground) or fans (underground).

Since no highly radioactive spent fuel has left any U.S. nuclear plant for 36 years, it's estimated that most plants now have in excess of 1,000 tons of it on-site.

If a "China syndrome" were to occur at one of these plants and molten fuel were to disrupt the storage pools or dry-cask areas, the release of radioactivity could be 10 times greater than Chernobyl, where the entire radioactive core evaporated. (In addition, these massive highly concentrated sources of toxic radioactivity are prime targets for terrorism.)

Yes, nuclear is clean in that it doesn't emit carbon dioxide. But the dirty little secret of radioactive wastes is that they are highly toxic, last for millennia and nobody wants them.

In a sane society, energy development would emphasize solar, wind and geothermal, which are actually clean in every aspect.

Bruce Molholt is a toxicologist in West Chester.
© Copyright 2008 Philly Online, LLC.