Author: Burt Webb

  • Geiger Readings for July 4, 2014

    My Geiger counter is in the shop for maintenance.

  • Radioactive Waste 85 -Russia and Norway Cooperate in Exploring Nuclear Dump in the Kara Sea

            I have blogged before about the nuclear waste situation in Russia. In one post, I discussed how Russia had been taking in illegal shipments of nuclear waste from European countries. I have also discussed how Russia has been dumping nuclear waste into the sea around the port of Murmansk. Now a report on the decades of Russian dumping into the Kara Sea of the Arctic Ocean has been provided by the Russians to the Norwegians. Norwegian officials are demanding high level talks with the Russians about their nuclear waste.

           The catalog of dumped nuclear waste and reactors in the Kara Sea is much larger than thought by the Norwegian authorities and the Russian authorities. The known waste dumps include “seventeen thousand containers of radioactive waste, nineteen ships containing radioactive waste, fourteen nuclear reactors, including five that still contain spent nuclear fuel; seven hundred and thirty seven other pieces of radioactively contaminated heavy machinery, and the K-27 nuclear submarine with its two reactors loaded with nuclear fuel.”

           Given that the Soviets and the Russians kept poor records of nuclear waste dumping, it is likely that the catalog provided to the Norwegians is not complete. The Russians and the Norwegians have formed a task force to investigate the nuclear waste in the Kara Sea. The task force will send an expedition to the Kara Sea area where the Soviet and Russian waste has been dumped. The Russians are eager to explore the same area of the Kara Sea for possible oil production. Some see the Russian report provided to the Norwegians as a veiled plea for help because the Russians cannot handle their nuclear waste problems on their own. There were joint expeditions before in 1992, 1993 and 1994 to map the extent of nuclear waste in the Kara Sea but the new report shows that a lot of waste dumping was excluded from these earlier expeditions.

            The K-27 submarine that was deliberately sunk in the Kara Sea in 1981 with two nuclear reactors full of spent nuclear fuel on board was not part of the initial report on nuclear waste that the Russians gave the Norwegians. Now it is being reported that it is possible that the spent nuclear fuel in the K-27 could achieve criticality and cause an explosion. The expedition will try to determine if the K-27 could be raised and whether or not it has been leaking radioactive materials.

            The Soviet Union and Russia have a very poor record when it comes to keeping track of nuclear waste dumping. They also have a poor record when it comes to insuring the safety of people living in the areas where nuclear waste has been dumped. Unfortunately, the Russian are dedicated to the use of nuclear power at home and the export of nuclear reactor technology and nuclear fuel to foreign companies. They are building new fast breeder reactors with the intent of producing nuclear fuel to compete with uranium fuel in the international marketplace. I fear that the Russian people are not being told the real costs and real dangers of nuclear power generation.

    Approximate location of the K-27 submarine:

  • Geiger Readings for July 3, 2014

    My Geiger counter is in the shop for maintenance.

  • Radioactive Waste 84 – France is Working on a Permanent Geological Repository for Nuclear Waste

             Nulcear waste disposal is a great unsolved problem. Geological repositories have been created by some nations but some have had to be closed because of unanticipated problems. In the U.S., years were spent working on a Yucca Mountain repository in Nevada before the project was cancelled in 1999. The best current estimate is that there will be no permanent geological repository in the U.S. before 2050. Other countries are moving ahead in creating new geological repositories for nuclear waste.

             France is currently dependent on fifty eight nuclear power reactors for about seventy five percent of its electricity.  In 2006, the French 1991 Waste Management Act was updated to declare that a permanent geological repository was the preferred solution to France’s nuclear waste disposal. There are about ten thousand cubic feet of high level radioactive wastes and about one million four hundred thousand cubic feet of long lived intermediate level radioactive wastes in France. These two categories of nuclear waste make up about ninety nine percent of the radioactive wastes generated by France’s nuclear power reactors over the past few decades.

             Work is starting on the creation of a new geological repository at Cigeo by Assystem, Cegelec and Spretec engineering firms. Cigeo will consist of disposal tunnels called galleries in a layer of clay near Bure, east of Paris. Twenty seven million dollars have been allocated for a four year project during which Assystem will undertake high-level studies followed by detailed design of the technical procedures for the transfer and storage of waste packages at Cigéo.

           The Assystem’s five month study will focus on creating specifications for Cigeo’s systems and procedures. These specifications will then be used to develop a license application. Assystem will also develop a “roadmap” for Cegelec and Spretec representing the best technical and economic solution to France’s nuclear waste storage problem.

           Andra, the French national radioactive waste disposal company, put out their plans for Cigeo for public comment in 2013. Based on the public input, Andra will conduct a pilot plant test where all of the disposal functions can be tested in real conditions. These include:

    ·       Technical measures to control operating risks

    ·       Capacity to remove packages being disposed of

    ·       Disposal monitoring sensors

    ·       Techniques for sealing cavities and galleries

     

              The public feedback included the desire to allow for easy removal of waste packages from the repository in the future. The public feedback also requested that the entire master plan for Cigeo’s development and operation be updated on a regular basis with input from all the different stakeholders as well as the French government.

               Next year, Andra will submit the Cigeo master plan to the French government along with optional plans for security and retrievability. They hope to have the license application ready for government review in 2017 with construction beginning in 2020 if the application is approved. Cigeo should be ready for a pilot test of the facility by 2025.

    Artist’s rendering of Cigeo site:    

        

  • Geiger Readings for July 2, 2014

    My Geiger counter is in the shop for maintenance.

  • Nuclear Reactors 140 – Experiments on Nuclear Core Meltdowns

             Corium is a name that was coined for the molten material that results when the fuel of a nuclear reactor melts down in a nuclear accident. It contains nuclear fuel, fission products, control rods, structural material, and chemical reaction products with air, water and steam. If the reactor core is breached, then there will also be molten concrete in the mix. There is currently a debate about the fate of the corium created during the nuclear disaster at Fukushima in March of 2011.

             In order to better understand exactly what happens when a nuclear reactor core melts down, researchers have carried out experiments with substitutue materials like lead and glass. Tests at U.S. Brookhaven National Laboratories used varying levels of water as they dropped molten lead into a hole in the ground referred to as a “drywell.” Unlike lead, corium continues to generate heat on its own and so it remains liquid for a longer time. However, the behavior of molten lead can be useful in the study of corium.

             Approximately ten ounces of lead were used in the tests, heated to seven hundred and fifty degrees Fahrenheit. The lead was placed in a modified tea strainer with used which had a more open mesh. The strainer was put on a ceramic pedestal. An aluminum tube was placed on top of the tea strainer to confine the lead like a reactor vessel. The holes in the tea strainer mimics the control rod holes in the bottom of a boiling water reactor.

             Experiments in Japan with molten lead had similar results although the researchers did not use any water. The molten lead flowed through the mesh in the tea strainer and pooled in the terra cotta flower pot being used for a pedestal. When some of the molten lead flowed out through a hole in the flower pot, it created a lump of cooled lead that had the shape of the foot of an elephant. This shape was also seen in corium that oozed out of the containment vessel at Chernobyl.

            At Fukushima, three of the reactors experienced a meltdown on March 11, 2011. The corium from the three reactors melted through the bottom of the reactrors during the first day of the disaster and is still sinking into the gound beneath the reactors. They think that the corium may be as much as thirty feet below the bottom of the reactors now. It is thought that there are three one hundred tons blobs of corium beneath Fukushima at around three thousands degrees Fahrenheit. Given the level of radioactivity and the ability of current technology, it will take thousands of years before the corium is cool enough for researders to find its exact location.

           A great deal of cooling water has been pumped into the wreckage of the reactors to prevent more explosions. This water becomes contaminated with radioactive materials and has been being captured and stored. Recently, the volume of water has exceeded the ablity of the operators of Fukushima to decontominate and they have started pumping the contaminated water directly into the Pacific Ocean.

    Three Mile Island Reactor after Meltdown:

     

    1.  

    1.             Inlet 2B

    2.             Inlet 1A

    3.             Cavity

    4.             Loose core debris

    5.             Crust

    6.              Previously molten material

    7.              Lower plenum debris

    8.              Possible region depleted in uranium

    9.              Ablated incore instrument guide

    10.            Hole in baffle plate

    11.            Coating of previously-molten material on bypass region interior surfaces

    12.            Upper grid dam

  • Geiger Readings for July 1, 2014

    My Geiger counter is in the shop for maintenance.