Where is the USA’s spent fuel? How is it stored?
Yesterday I wrote about a controversy over whether spent fuel could ignite if the water in the spent fuel pools were lost, either by leakage or by boiloff when cooling capability was impaired (say, by loss of electricity to the spent fuel cooling system’s pumps). I wrote that the recommendation of the National Academies had been to store spent fuel rods in dry casks, in order to reduce vulnerability to fire in the spent fuel pit should cooling and/or water be lost. I wrote that the industry lobbyist group, NEI (Nuclear Energy Institute)’s fact sheet on Fukushima dated 3/15/2011 (and still online as of yesterday) assured us that it was “virtually impossible” for the spent fuel to ignite, even in such a circumstance.
I didn’t have anything to relate about what U.S. plants had actually done in response to the National Academies’ recommendation that the spent fuel be stored in dry casks in yesterday’s post. Now there is an article in The Miami Herald (3/17/2011) about that:
U.S. nuclear plants store more spent fuel than Japan’s, experts say. ( http://www.miamiherald.com/2011/03/17/2120693/us-nuclear-plants-store-more-spent.html )
The article gives us some insight into how the U.S. NRC has approached the matter:
“Burnell said that research after the Sept. 11, 2001, attacks and extensive reviews of plant operations show ‘that it is possible even under emergency conditions to maintain an appropriate level of water in a spent fuel pool using very simple techniques’ even under conditions where radiation levels would be high.”
But, as the Miami Herald points out, “High radiation levels have deterred efforts in Japan to dump water into the pools.”
This is beyond design basis. The NRC analysis doesn’t have an account of what happens for the scenario that the Japanese faced this past week. Nature doesn’t seem to respect the limits of the NRC’s analysis. It doesn’t stay within those limits.
So, should anything be done? Some certainly feel that way — in fact, have felt that way for some time. ”Lyman and others have long called on the NRC to require plant owners to move spent fuel to dry casks. Lyman was part of a group that wrote in a separate 2004 study published in the journal Science and Global Security that a large radiation release from a fire in a storage pool could result in thousands of cancer deaths and require billions of dollars for decontamination.”
With all this advice, you’d think the utilities might find it in their best interest to invest in those casks. But, relates the Miami Herald: ”Princeton professor Frank von Hippel, another author, said in an e-mail on Thursday that the utilities objected to spending $8 billion on casks and the NRC didn’t require them to do so.”
Maybe the utilities will feel differently next week. Let’s hope so.
Read the rest of the article about it in The Miami Herald: http://www.miamiherald.com/2011/03/17/2120693/us-nuclear-plants-store-more-spent.html#ixzz1GvUykDKg
Japan’s Fukushima nuclear plant – spent fuel fire (revised 17 March 2011)
Multiple reports this week indicated that there was a fire in the spent fuel pit, or pool, of one of the reactors at Fukushima. I remember when the National Academies of Sciences’ report about spent fuel storage came out. I knew that the report had concluded that the safest means of storage for spent fuel currently available was in above ground casks, at current reactor sites. What I didn’t realize was how contentious the findings in that report about the dangers of leaving spent fuel in spent fuel pits (pools) were at the time.
To explain: Spent fuel pits are basically large pools, much like swimming pools, with skimmers and circulation pumps; the circulation loop also removes the heat produced by the spent fuel rods. The spent fuel pools are located in the nuclear power plant, usually not too far from the reactor. Most were originally sized to hold just a few years’ worth of fuel, since the plan was for the Federal government (Dept of Energy) to come and remove the spent fuel and store it in a national repository. As year after year passed without a national fuel repository being ready to receive spent fuel, most U.S. utilities asked for permission to crowd the spent fuel rod assemblies closer and closer together.
Science magazine just published a short piece pointing out that the report had concluded that the risk of a fire in a spent fuel pit at a US reactor was a real possibility, but that US regulators had not at that time dealt with the issue. The report had been requested by Congress, largely, it seems, because of questions about about whether spent fuel rods might be stolen from spent fuel pools and used to build dirty bombs. That was unlikely, the report concluded, but draining the spent fuel pools would pose a danger, given how closely the rods were packed in some plants. The report is aimed at the danger posed by terrorist attacks, not by natural disasters.
The press release from 2005 is here: http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=11263. The public version of the report can be read online for free, here: http://www.nap.edu/catalog.php?record_id=11263#toc
Further, the article says:
“Industry and academic scientists have long been at odds over the risk of such an event. U.S. regulators have mostly sided with industry, which before today said such a fire was impossible. Today, they appear to have changed that view.”
The industry lobby group NEI (Nuclear Energy Institute) has “updated” their fact sheet since the fire at Fukushima this week, but how this came about is interesting. According to the article in Science, at the time the fire in the spent fuel pit at Fukushima first occurred, NEI’s fact sheet said:
“There has been some speculation that, if the used fuel pool were completely drained, the zirconium cladding might ignite and a “zirconium fire” might occur. Studies performed by the Department of Energy indicate that it is virtually impossible to ignite zirconium tubing.”,
but, upon being asked for a copy of the Department of Energy study that its fact sheet cited, NEI deleted the latter sentence but did not provide any such study.
The Wall Street Journal’s article about the dangers of fire in spent fuel pools today (“Spent Fuel Rods at Plant Pose Big Risk”) does not mention the controversy, but it is striking that no industry lobbyists are not quoted on the issue.
The Science magazine article reporting this is here: http://news.sciencemag.org/scienceinsider/2011/03/contention-over-risk-of-fire-fro.html
The Wall Street Journal article is here:http://online.wsj.com/article/SB10001424052748704396504576205000098975380.html?mod=mktw
NEI’s fact sheet dated March 15th, 2011 as of this writing, is at http://resources.nei.org/documents/japan/Used_Fuel_Pools_Key_Facts.pdf