Nuclear power radioactive waste storage

The last stage in the disposal of nuclear power station waste is long-term secure permanent storage of the solidified high, medium and low activity waste. Annually 5000 m- of radioactive waste is produced in the Federal Republic of Germany, of which only half comes from nuclear power stations. 

Half-lives span a very wide range (Table 17.5). Consider strontium-90, for which the half-life is 28 a. This nuclide is present in nuclear fallout, the fine dust that settles from clouds of airborne particles after the explosion of a nuclear bomb, and may also be present in the accidental release of radioactive materials into the air. Because it is chemically very similar to calcium, strontium may accompany that element through the environment and become incorporated into bones once there, it continues to emit radiation for many years. About 10 half-lives (for strontium-90, 280 a) must pass before the activity of a sample has fallen to 1/1000 of its initial value. Iodine-131, which was released in the accidental fire at the Chernobyl nuclear power plant, has a half-life of only 8.05 d, but it accumulates in the thyroid gland. Several cases of thyroid cancer have been linked to iodine-131 exposure from the accident. Plutonium-239 has a half-life of 24 ka (24000 years). Consequently, very long term storage facilities are required for plutonium waste, and land contaminated with plutonium cannot be inhabited again for thousands of years without expensive remediation efforts. 

As of March 2003, there were 26 spent fuel storage facilities in the United States located in 21 states. A total of about 160,000 spent fuel units containing about 45,000 short tons (41,000 metric tons) of radioactive waste were stored on-site at nuclear power plants and off-site at special storage areas. More than 97 percent of the wastes were still being held at on-site facilities the rest had been transported to off-site locations. 

In the past, a number of polluters have used temporary waste storage means, such as aboveground tanks. Storage of radioactive wastes at nuclear power facilities is another example. In-plant storage or nearby polluter-owned sites must meet all current pollution regulations These practices have been costly in retrospect. They have comprised many of the targets of the so-called Superfund. 

One of the most important applications of nuclear and radiochemistry is in the area of nuclear power. Chemistry and chemical processes are intimately involved in reactor operation, the preparation and processing of reactor fuel, and the storage and ultimate disposal of radioactive waste. In this chapter, we shall examine some of the most important chemistry associated with nuclear power. 

The fourth ARW also addressed the problems necessitating urgent solution. First and foremost those were the issues of safe management of spent nuclear fuel and, especially, of spent fuel of damaged nuclear-powered installations. Secondly, temporary and long-term storage and ultimate disposal of spent nuclear fuel and radioactive waste also... 

However no development of nuclear power industry is possible without appropriate solution of a variety of complex and expensive problems related to transportation, storage, processing and disposal of radioactive waste generated during both normal operation and decommissioning of nuclear facilities including Nuclear Submarines (NS). 

Indeed, the French have demonstrated that nuclear power can be economically and politically feasible. France, which uses breeder reactors to provide most of its electricity, has an excellent safety record and is pioneering new methods for the storage of radioactive wastes. 

World-wide the production of energy by nuclear power amounts to about 470 GWe (1995) and increases by about 4% per year, although the problems with respect to the storage of the radioactive waste (fission products and actinides) are not yet solved in a satisfactory way. 

Radioactive waste treatment applications have been reported [3-9] for the laundry wastes from nuclear power plants and mixed laboratory wastes. Another interesting application of reverse osmosis process is in decontamination of boric acid wastes from pressurized heavy water reactors (PHWRs), which allows for the recovery of boric acid, by using the fact that the latter is relatively undissociated and hence wdl pass with water through the membrane while most of the radioactivity is retained [10]. Reverse osmosis was evaluated for treating fuel storage pool water, and for low-level liquid effluents from reprocessing plants. 

One of the problems associated with the storage of radioactive wastes from nuclear power plants is that some of the nuclides remain radioactive for a very long time. An example is plutonium-239, which has a half-life of 2.44 x 10 years. What fraction of plutonium-239 is left after 9.76 x 10 years ... 

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