John Kerry has been much lampooned for saying that he "actually voted for" funding U.S. troops in Iraq "before he voted against it."

He's in a another contradictory position when it comes to nuclear energy.

Kerry's Web site states that "nuclear power can play an essential role in providing affordable energy while reducing the risk of climate change." His aides also say he is for nuclear power.

So far, so good. But then on a recent campaign stop in Las Vegas — about 100 miles away from the planned Yucca Mountain (search) site for the long-term disposal of waste from nuclear power plants — Kerry said, "When I'm president of the United States, I'll tell you about Yucca Mountain: Not on my watch."

The realty of the matter, however, is that you can't be "for" nuclear energy (search) but "against" Yucca Mountain.

Yucca Mountain is on a remote desert on federally protected land within the secure boundaries of the former nuclear-weapons testing grounds known as the Nevada Test Site (search) — that is, Yucca is in the middle of nowhere.

The idea is to place sealed containers of radioactive used fuel from nuclear power plants in underground tunnels deep below Yucca Mountain. This system, which has been in the works for about 25 years, is designed to prevent radiation from the waste leaking into the environment for (supposedly) tens of thousands of years.

The need for Yucca Mountain is simple. Without it, nuclear power plants, which provide about 20 percent of U.S. electric power, may have to start shutting down in the near future.

Used nuclear fuel is currently stored on-site either in steel-lined concrete pools filled with water or, in situations where the pools are full, in above-ground dry-storage facilities.

Under a 1982 federal law, used fuel was supposed to be transported to a centralized storage facility — such as Yucca Mountain — by 1998. But since the Yucca Mountain site was selected for the repository in 1987, anti-nuclear activists have been able to delay progress.

Not only have the activists whipped up public fear of Yucca Mountain among Nevadans, but they've also been successful in getting the U.S. Environmental Protection Agency to set overly stringent, if not flat-out impossible-to-meet, waste-containment standards for the site.

Perhaps the most outrageous requirement is that the Department of Energy ensure that used fuel stored at Yucca Mountain remain contained on-site for 10,000 years — a period of time roughly twice as long as all of recorded history.

As if that standard weren't tough enough to meet, a federal court recently ruled that 10,000 years was not long enough.

Yucca Mountain, the court said, must function acceptably for hundreds of thousands of years.

Needless to say, it doesn't look like Yucca Mountain will be opening on schedule, if ever, and that may be a major problem.

Although nuclear power plants were designed to store at least a decade's worth of used fuel, they are now running out of space.

By 2010, which is the earliest date that Yucca Mountain could go into operation in the best of circumstances, 78 of the nation's 103 nuclear plants will not have space for used fuel in their pools.

Though fuel may be stored in the above-ground dry storage containers, this is expensive — $1 million for a container stored outside on a concrete pad — and some states have already moved to limit the expansion of these facilities, thanks to pressure from anti-nuclear activists.

So why do anti-nuclear activists oppose Yucca Mountain, especially when it would allow the safe burial of nuclear waste (search) in the middle of nowhere rather than the above-ground storage of waste near populated centers?

The activists don't really oppose the burial of nuclear waste under all conditions, but they know that the longer Yucca Mountain is delayed, the more difficulty nuclear power plants will have storing used fuel — so they'll have to produce less of it.

Anti-nuclear activists, in fact, hope to shut down the nuclear power industry by making it impossible for nuclear plants to store used fuel anywhere.

This strategy is akin to the adolescent prank of putting a banana in an automobile tailpipe — without anywhere for exhaust to go, the engine will stall.

There is no practical centralized repository alternative to Yucca Mountain, a site that has been under study and development for decades. Any alternative site would likely absorb a similar amount of time — something the nuclear-power industry may not have.

Given that nuclear power is the only realistic alternative to burning fossil fuels (search) for electricity generation — and Sen. Kerry is a believer in man-made global warming — it's possible, I suppose, that he could always reverse his position on Yucca Mountain if elected.

Nah, he'd never do that.

Steven Milloy is the publisher of JunkScience.com, an adjunct scholar at the Cato Institute and the author of "Junk Science Judo: Self-Defense Against Health Scares and Scams" (Cato Institute, 2001).

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