Nuclear waste will last a lot longer than climate change
Preface. One of the most tragic aspects of peak oil is that it is very unlikely once energy descent begins that oil will be expended to clean up our nuclear mess. Or before descent either. Anyone who survives peak fossil fuels and after that, rising sea levels and extreme weather from climate change, will still be faced with nuclear waste as a deadly pollutant and potential weapon.
According to Archer (2008): “… there are components of nuclear material that have a long lifetime, such as the isotopes plutonium 239 (24,000 year half-life), thorium 230 (80,000 years), and iodine 129 (15.7 million years). Ideally, these substances must be stored and isolated from reaching ground water until they decay, but the lifetimes are so immense that it is hard to believe or to prove that this can be done”.
Below are summaries of two articles on nuclear waste.
Alice Friedemann www.energyskeptic.com author of “When Trucks Stop Running: Energy and the Future of Transportation”, 2015, Springer, Barriers to Making Algal Biofuels, and “Crunch! Whole Grain Artisan Chips and Crackers”. Podcasts: Collapse Chronicles, Derrick Jensen, Practical Prepping, KunstlerCast 253, KunstlerCast278, Peak Prosperity , XX2 report
Ro, C. 2019. The Staggering Timescales Of Nuclear Waste Disposal. Forbes.
This most potent form of nuclear waste needs to be safely stored for up to a million years. Yet existing and planned nuclear waste sites operate on much shorter timeframes: often 10,000 or 100,000 years. These are still such unimaginably vast lengths of time that regulatory authorities decide on them, in part, based on how long ice ages are expected to last.
Strategies remain worryingly short-term, on a nuclear timescale. Chernobyl’s destroyed reactor no. 4, for instance, was encased in July 2019 in a massive steel “sarcophagus” that will only last 100 years. Not only will containers like this one fall short of the timescales needed for sufficient storage, but no country has allotted enough funds to cover nuclear waste disposal. In France and the US, according to the recently published World Nuclear Waste Report, the funding allocation only covers a third of the estimated costs. And the cost estimates that do exist rarely extend beyond several decades.
Essentially, we’re hoping that things will work out once future generations develop better technologies and find more funds to manage nuclear waste. It’s one of the most striking examples of the dangers of short-term thinking.
Fred Pearce. 7 March 2012. Resilient reactors: Nuclear built to last centuries. New Scientist.
All nuclear plants have to be shut down within a few decades because they become too radioactive, making them so brittle they’re likely to crumble.
Decommissioning can take longer than the time that the plant was operational. This is why only 17 reactors have been decommissioned, and well over a hundred are waiting to be decommissioned (110 commercial plants, 46 prototypes, 250 research reactors), yet meanwhile we keep building more of them.
Building longer lasting new types of nuclear power plants
Fast-breeders were among the first research reactors. But they have never been used for commercial power generation. There’s just one problem. Burke says the new reactors aren’t being designed with greater longevity in mind, and the intense reactions in a fast-breeder could reduce its lifetime to just a couple of decades. A critical issue is finding materials that can better withstand the stresses created by the chain reactions inside a nuclear reactor.Uranium atoms are bombarded with neutrons that they absorb. The splitting uranium atoms create energy and more neutrons to split yet more atoms, a process that eventually erodes the steel reactor vessel and plumbing.
The breakdown that leads to a reactor’s decline happens on the microscopic level when the steel alloys of the reactor vessels undergo small changes in their crystalline structures. These metals are made up of grains, single crystals in which atoms are lined up, tightly packed, in a precise order. The boundaries between the grains, where the atoms are slightly less densely packed, are the weak links in this structure. Years of neutron bombardment jar the atoms in the crystals until some lose their place, creating gaps in the structure, mostly at the grain boundaries. The steel alloys – which contain nickel, chromium and other metals – then undergo something called segregation, in which these other metals and impurities migrate to fill the gaps. These migrations accumulate until, eventually, they cause the metal to lose shape, swell, harden and become brittle. Gases can accumulate in the cracks, causing corrosion.
A reactor that does not need to be shut down after a few decades will do a lot to limit the world’s stockpile of nuclear waste. But eventually, even these will need to be decommissioned, a process that generates vast volumes of what the industry calls “intermediate-level” waste.
Despite its innocuous name, intermediate-level waste is highly radioactive and will one day have to be packaged and buried in rocks hundreds of meters underground, while its radioactivity decays over thousands of years. It is irradiated by the same mechanism that erodes the machinery in a nuclear power plant, namely neutron bombardment.
Nuclear waste is highly radioactive and remains lethal for thousands of years and is without doubt nuclear energy’s biggest nightmare. Efforts to “green” nuclear energy have focused almost exclusively on finding ways to get rid of it. The most practical option is disposal in repositories deep underground. Yet, seven decades into the nuclear age, not one country has built a final resting place for its most toxic nuclear junk. So along with the legacy waste of cold-war-era bomb making, it will accumulate in storage above ground – unless the new reactors can turn some of that waste back into fuel.
Without a comprehensive clean-up plan, the wider world is unlikely to embrace any dreams of a nuclear renaissance.
Archer, D., et al. 2008. The millennial atmospheric lifetime of anthropogenic CO2. Climactic Change 90: 283-297. https://geosci.uchicago.edu/~archer/reprints/archer.2008.tail_implications.pdf
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