Wastes
The waste materials from nuclear energy are at most a hypothetical concern. No person has ever been harmed by them. Despite that, people who oppose nuclear energy do so mainly because the wastes stay radioactive for a very long time, even hundreds of thousands of years. It's odd that the same people don't have problems with coal wastes, which pile up in vast heaps and sludge ponds that stay toxic forever.[source]
Until recently, the plan was to bury the wastes in geological structures where they would be safe until the radioactivity decayed away. But now the plan is to reprocess the wastes to separate out the valuable uranium and transuranic actinides to use as fuel. The remaining wastes are only 3% of what was there before and lose their toxicity in much less time, hundreds of years instead of hundreds of thousands.[source] Many geologic places, such as caves or abandoned mines, could store those wastes safely. Besides that, proven technology exists to irradiate the wastes into other, shorter-lived materials.[source] To deal with the wastes this way doesn't require any technological breakthroughs, just a political decision.
Bomb Proliferation
There is a common misunderstanding that nuclear power plants are a requirement for making bombs. That is not the case, as explained by Hans Blix, a former Director of the IAEA, the United Nations agency responsible for preventing proliferation [source]:
"A phasing out of nuclear power in some or all states would not lead to the scrapping of a single nuclear bomb.
"States can have nuclear weapons without nuclear power though it is not common today. Israel is a case in point. It has no nuclear power but is assessed to have some 200 nuclear warheads. For a long time China had only the weapons. Indeed, most nuclear weapons states, including the US, had weapons before they had power. "
Despite that, people have a concern that nuclear fuel could be diverted and used to make a bomb by someone who shouldn't have one. This concern overlooks the fact that, even assuming someone could defeat the security measures for protecting the material and somehow ship it to his own facility, the material has to be treated with chemical separation and isotope separation and enrichment. This is a major industrial operation. In every case where it has been done, it required a nation's best minds and vast capital resources. And there still remains the problem of learning how to make a bomb go off. If a nation decides to make a bomb and is willing to make the investment, it can make it from natural uranium; stealing fuel is not a requirement.
Dirty Bombs
A possibility of dirty bombs comes up in some discussions. The concern is that a terrorist could get his hands on spent fuel and blow it up with conventional explosives. That is a possibility, and puts it in the class of other threats, such as chlorine or ammonia or explosives made from fertilizer. But spent fuel is unattractive to terrorists for several reasons. One is that it's monitored in shipping and it's highly likely that the thieves would be caught and the terrorist plot would be exposed. Another is that it has to be heavily shielded so it would take a huge explosion to spread the waste. Another is that the radioactive material is easy to detect; people who are contaminated can be decontaminated quickly and cleanup crews can clean up the contaminated area. Of all the things we have to concern ourselves with, dirty bombs don't rank very high.
Conclusion
This finishes up the initial series of blogs. What they show is the following:
- Global warming is happening.
- Global warming is caused by artificial greenhouse gas, mainly carbon dioxide.
- There's a possibility global warming could reach a tipping point, after which there's no way to fix the problem.
- To prevent global warming, carbon-dioxide emissions have to be minimized.
- To minimize carbon-dioxide emissions will require all the renewable energy we can manage, all the nuclear plants we can build, and more conservation than anyone wants.
In future blogs we'll cover some of the same issues in more detail.
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