The Environmental Protection Agency current plans to set a 1,000,000 year safety threshold for the high level nuclear waste dump at Yucca Mountain in Nevada. The theory? It takes a million years for high level nuclear waste radioactivity to fall to background levels. Setting high standards is a good thing, right? What is wrong with this approach?
There is nothing wrong with trying to use the best possible safety standards. But, the problem with this standard is that it rules out options that may be the best available options simply because they can't last 1,000,000 years, a ridiculous time period considering that human civilization is only about 11,000 years old, and homo sapiens haven't even been around that long.
We do not have the luxury of saying that nuclear waste will be disposed of in a place that will be safe for 1,000,000 years or not at all. High level nuclear waste exists now. It appears that proponents and opponents of the plan agree that there are about 40,000 tons of high level nuclear waste (including about 500 tons of weapons grade material) in existence now from the entire history of nuclear energy and weapons operations in the United States, and that there will be about 70,000 tons by 2015 or so, when Yucca Mountain would be ready to come on line, with Yucca Mountain having a proposed capacity of about 77,000 tons. It is now held in temporary facilities that we'll be lucky if we can manage to keep safe for a few decades, at nuclear power and nuclear weapons facilities across the nation. The right question is not, how long does it take for high level nuclear waste to become inert. The right question is, what is the safest practically available option for disposing of the high level nuclear waste that exists now. If Yucca Mountain can be proven safe for only 200 years, but the next best option is safe for only 40 years, the decision is a no brainer: move the high level nuclear waste to Yucca Mountain.
If there is a safer option than Yucca Mountain out there, that's great. Somebody should tell us what it is and push for it as an alternative. But, the status quo is clearly worse than the Yucca Mountain option. Opponents of Yucca Mountain argue that existing storage sites are safe for 100 years, that the dangers of moving the waste outweight the benefits of moving it, and that we should study more carefully before finding a long term solution. Some of those local sites may be safe for 100 years. But, I'm deeply skeptical of the claim that all, or even most of them will be safe that long. And, even if they are right, then 100 years plus a transporation risk premium, and not 1,000,000 years is the proper safety standard for Yucca Mountain. Others argue that nuclear waste recycling programs are the best choice, but nothing prevents those kinds of activities from taking place at Yucca Mountain. Another site in Utah has been considered for about 40,000 tons of material, but it is hard to tell if that is simply NIMBY politics, or if it is actually safer.
Strictly speaking, this analysis applies only to existing high level nuclear waste. When it comes to the question of new nuclear weapons production and nuclear power production the proper question is: On balance is the environmental harm caused by storing high level nuclear waste at Yucca Mountain more serious than the environmental harm caused by alternatives such as using coal to generate electricity? This is a closer question, but to do it right you have to look at both potential sources of environmental harm over the same time horizon and measure them with the same measuring stick. The environmental harm caused by the alternatives, and the human harm caused by the alternatives considerably lower the bar on what we need to expect of nuclear waste disposal to still make nuclear power a more environmentally sound option than the alternatives.