Today I’m thinking about reprocessing. Ever since Yucca Mountain got canned, there have been whispers of possible U.S. government support for a closed fuel cycle. Disregarding for the moment proliferation, energy needs and cost concerns, what effect would reprocessing have on nuclear waste?
A recent Wall Street Journal blog post states “The appeal of nuclear fuel reprocessing is that it can reduce the amount of nuclear waste produced by nuclear power plants”. Is that statement true? There are a whole host of websites from organizations I am unfamiliar with that say no. These include The Public Citizen [and are France and England really still dumping their nasties into the sea?], The Institute for Energy and Environmental Research, and The Bulletin of the Atomic Scientists.
The World Nuclear Organization, which appears to represent the nuclear industry, says
“Seven UO2 fuel assemblies give rise to one MOX [mixed-oxide fuel; PuO2+UO2] assembly plus some vitrified high-level waste, resulting in only about 35% of the volume, mass and cost of disposal.” Where are any of these people getting their information? I assume that the effect on waste volume and radioactivity would also depend on the reprocessing method (PUREX is standard, but there are others), and I would like to see an analysis and comparison for the various reprocessing methods.
One possible perk of reprocessing is that separating out individual elements and isotopes would allow us to create tailored waste forms for each one. My PhD advisor (Ewing) has been plugging tailored waste forms for years.
Wednesday, November 18, 2009
Saturday, November 14, 2009
Health Physics
We’re at the tail end of National Radiation Protection Professionals Week. These professionals are known as health physicists (an intentionally confusing name, according to bloggers at the EPA), and they make all the nifty radiochemistry, nuclear reactors, and safe cleanup of rad materials possible. Thanks HP’s!
Talk About Nuclear Energy
Earlier this week I attended a Sierra Club house party where we saw a preview of a documentary about mountain top removal for mining coal. Towards the end, the movie talked about alternatives to coal – reducing our energy usage and using wind, solar, and geothermal energy. Conspicuously absent from the presentation was nuclear energy. I found this shocking. Yes, nuclear energy has its problems (note the topic of this blog), but to not mention it as a possibility at all struck me as bizarre and perhaps even a little dishonest.
In 2007, 19.4% of U.S. energy came from nuclear reactors . That’s almost 1/5. If you want to talk seriously about alternatives to coal (which contributed a whopping 48.5% of the U.S. energy in 2007), the nuclear option should at least be mentioned. I don’t consider myself to be either a major supporter or opponent of nuclear energy. What I do strongly advocate is that it be part of the conversation.
Along these lines, there is an initiative in England called KNOO – Keeping the Nuclear Option Open. One of their four work packages is entirely dedicated to the issue of nuclear waste.
In 2007, 19.4% of U.S. energy came from nuclear reactors . That’s almost 1/5. If you want to talk seriously about alternatives to coal (which contributed a whopping 48.5% of the U.S. energy in 2007), the nuclear option should at least be mentioned. I don’t consider myself to be either a major supporter or opponent of nuclear energy. What I do strongly advocate is that it be part of the conversation.
Along these lines, there is an initiative in England called KNOO – Keeping the Nuclear Option Open. One of their four work packages is entirely dedicated to the issue of nuclear waste.
Hanford and the Nevada Test Site
Wow. I got my first comment! Thanks for the encouragement, Heart of America Northwest, oh ye of the Hanford cleanup!
My understanding is that after reprocessing (making the pure Pu that was used to bomb Japanese civilians in Nagasaki), the workers at Hanford just threw all the random leftover radioactive stuff together in a series of (now leaky) metal drums. This makes for some fabulously weird chemistry. Technetium (Tc), for instance, typically forms the pertechnetate ion (TcO4-), meaning it has an oxidation state (implied charge) of +7. (It can also form +4 compounds like TcO2 in more reduced environments.) In Hanford tanks, it has been found in the +1 state complexed by carbonyl ions. So weird.
Weird and gross. The site has been described as “the most contaminated of the nation's nuclear weapons plants” by the NY Times and “the nation's most contaminated nuclear site” by the Associated Press.
I was a little surprised then to read the following in the LA Times:
“The [Nevada] test site receives about $65 million a year from the [Department of Energy’s] $5.5-billion annual nuclear cleanup budget. By contrast, about $1.8 billion a year is spent on the Hanford plutonium production site in Washington state, even though soil and water contamination there is one-thousandth as severe as in Nevada.” One-thousandth! Where are these numbers from? Can Hanford still be the winner on non-soil and non-water contamination? What exactly is contaminated then?
My understanding is that after reprocessing (making the pure Pu that was used to bomb Japanese civilians in Nagasaki), the workers at Hanford just threw all the random leftover radioactive stuff together in a series of (now leaky) metal drums. This makes for some fabulously weird chemistry. Technetium (Tc), for instance, typically forms the pertechnetate ion (TcO4-), meaning it has an oxidation state (implied charge) of +7. (It can also form +4 compounds like TcO2 in more reduced environments.) In Hanford tanks, it has been found in the +1 state complexed by carbonyl ions. So weird.
Weird and gross. The site has been described as “the most contaminated of the nation's nuclear weapons plants” by the NY Times and “the nation's most contaminated nuclear site” by the Associated Press.
I was a little surprised then to read the following in the LA Times:
“The [Nevada] test site receives about $65 million a year from the [Department of Energy’s] $5.5-billion annual nuclear cleanup budget. By contrast, about $1.8 billion a year is spent on the Hanford plutonium production site in Washington state, even though soil and water contamination there is one-thousandth as severe as in Nevada.” One-thousandth! Where are these numbers from? Can Hanford still be the winner on non-soil and non-water contamination? What exactly is contaminated then?
Sunday, November 1, 2009
National Academies Report on Hidden Costs of Energy Production
The National Research Council has a new report that tries to estimate the cost in dollars of energy production and consumption in the U.S. Mostly their focus is on hydrocarbons, air pollution, and global warming, but they do spend some time looking at nuclear energy, mostly in the chapter called Energy for Electricity. Here’s a paragraph from their summary:
The life-cycle damages of wind power, which produces just over 1 percent of U.S. electricity but has large growth potential, are small compared with those from coal and natural gas. So are the damages associated with normal operation of the nation's 104 nuclear reactors, which provide almost 20 percent of the country’s electricity. But the life cycle of nuclear power does pose some risks; if uranium mining activities contaminate ground or surface water, for example, people could potentially be exposed to radon or other radionuclides; this risk is borne mostly by other nations, the report says, because the U.S. mines only 5 percent of the world’s uranium. The potential risks from a proposed long-term facility for storing high-level radioactive waste need further evaluation before they can be quantified. Life-cycle CO2 emissions from nuclear, wind, biomass, and solar power appear to be negligible when compared with fossil fuels. [italics mine]
That’s seems fair. One would like to know, for instance, if, when, and where we’re going to bury the nasties before we go estimating the immediate cost, much less the “hidden” one. I was struck by the implied assumption that there would be a long-term facility and that’s all they would need to worry about. What are the risks and hidden costs of storing the waste indefinitely on-site? Of reprocessing, if we want to consider it more? Of transporting the waste to the long-term storage? This topic could use its own report.
The life-cycle damages of wind power, which produces just over 1 percent of U.S. electricity but has large growth potential, are small compared with those from coal and natural gas. So are the damages associated with normal operation of the nation's 104 nuclear reactors, which provide almost 20 percent of the country’s electricity. But the life cycle of nuclear power does pose some risks; if uranium mining activities contaminate ground or surface water, for example, people could potentially be exposed to radon or other radionuclides; this risk is borne mostly by other nations, the report says, because the U.S. mines only 5 percent of the world’s uranium. The potential risks from a proposed long-term facility for storing high-level radioactive waste need further evaluation before they can be quantified. Life-cycle CO2 emissions from nuclear, wind, biomass, and solar power appear to be negligible when compared with fossil fuels. [italics mine]
That’s seems fair. One would like to know, for instance, if, when, and where we’re going to bury the nasties before we go estimating the immediate cost, much less the “hidden” one. I was struck by the implied assumption that there would be a long-term facility and that’s all they would need to worry about. What are the risks and hidden costs of storing the waste indefinitely on-site? Of reprocessing, if we want to consider it more? Of transporting the waste to the long-term storage? This topic could use its own report.
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