Inventories of radioactive waste

The site currently contains very large inventories of radioactive waste. This is principally present as spent fuel, in the dry storage units (Tanks 2A, 2B and 3 A, Figmes 1 and 2). The potential inventory in the three dry storage units is of the order of lO Bq. Another very contaminated facility is Building 5, the former pond storage facility for spent fuel. 

The first ocean dumping of radioactive waste was conducted by the USA in 1946 some 80 km off the coast of California. The International Atomic Energy Agency (IAEA) published in August 1999 an Inventory of radioactive waste disposal at sea according to which the disposal areas and the radioactivity can be listed as shown in Table 1. 

IAEA (1999) Inventory of Radioactive Waste Disposals at Sea. IAEA-TECDOC-1105 Vienna International Atomic Energy Agency, pp. 24 A.1-A.22. 

The waste storage area in Room 109 is bounded by the permanent and mobile walls, ceiling and floor. The walls, doors, and ceiling provide significant shielding for the very high inventory of radioactive waste which will be stored in this room. They also provide a confinement boundary to control the migration of contamination. 

Of particular relevance is the inherent hazard represented by the radioactive inventory of the waste and is the summed product of the activity (Bq) of each radionuclide present and its corresponding Specific Instantaneous Toxic Potential (SITP). This can be adjusted for decay for longer timescales and it is usual to employ the full radionuclide inventory for waste streams as sampled and quantified by Magnox Electric Ltd and reported in the U.K. Radioactive Waste Inventory. ... 

The magnitude of the consequences will obviously be a function of the radioactive inventory of the waste repository at the time when the sequence starts. As this inventory decreases by natural decay, the consequences will also decrease and will eventually drop below the level of significance. 

The Room 108 and Room 109 shield doors are normally In the up position to provide shielding from the significant radiological inventory that will exist in Room 109. Shield door 3A will be lowered for the (remote) placement of radioactive waste into Room 109 for storage. Shield door 2A will be lowered for the (remote) removal of radioactive waste from Room 109. Thus, the safety functions applicable to the shield door controls are ... 

Mr. Kazakov discussed problems associated with contamination from the Chernobyl nuclear accident. The first problem is in characterising what portion of the contaminated material in the exclusion zone should be considered radioactive waste and how to deal with it remove it or possibly use materials for construction. Consideration of the extent to which contaminated materials should be removed, as radioactive waste, presents a problem as well. This is related to the second problem in properly characterising the total inventory of the radioactive waste. The waste is characterised at temporary locations of radioactive waste (TLPRW) and radioactive waste burial sites (RWBS). Although there is a great deal of documented information on the locations, volumes and activities, it is unclear whether to categorise the radioactive waste by specific activity, volume or presence of transuranic and fissionable elements in the radioactive waste. 

Most of the wastes dumped was low- and intermediate-level, but spent fuel and reactors fi-om nuclear submarines introduce high-level wastes. Since the time of the dumping total inventory of radioactivity has reduced due to the natural decay of radionuclides. Some of calculations suggest that less than 130,000 curies remains in the reactors and spent fuel deposited in the Arctic [OTA, p. 49]. 

U.S. Department of Energy. (1996) Integrated Data Base Report 1995 U.S. Spent Nuclear Fuel and Radioactive Waste Inventories, Projections and Characteristics, DOE/RW-0006, Revision 12. Washington, DC Author. 

DOE. 1999. Inventory and characteristics of spent nuclear fuel high level radioactive waste and other... 

By combining the findings of Cacchione, Drake and the results reported here, a coherent model can be proposed to explain the deposition inventory of the radionuclides. The down-canyon current transports large quantities of sediment toward the radioactive waste disposal site at 4000 m. Within the upper canyon, fine material is transported the furthest. Near the mouth of the canyon, sediment erosion of the walls occurs due to the down-canyon currents meeting a proposed opposing on-shore bottom current. The eroded material from the walls is transported and the finer material is deposited in eddies formed where the two currents meet. 

Existing chemical substances do not have to be notified. These are defined as those listed on the European Inventory of Existing Chemical Substances (EINECS) (a. 1), a list of approximately 100,000 substances reported as being supplied in the EU during the reporting period of 1 January 1971 to 18 September 1981 (389, 394). Also the DSD does not apply to medicinal products, cosmetic products, wastes, foodstuffs, pesticides, biocides and radioactive substances. 

Radioactive waste a comparison of U.S. military and civilian inventories". 

Table 16.5 lists the surrogate (simulated) waste streams that were part of this study. The ash stream represents radioactive waste from the inventory of US Department of Energy (DOE) facilities. The Delphi DETOX streams are secondary waste generated during destruction of organics from similar waste streams [57]. The soil represents the waste from Argonne National Laboratory s inventory that was included in a site treatment plan for actual treatment. 

Five-gallon size waste forms were fabricated. Typical waste loading was 35-40 wt%. A small amount of potassium sulfide was added to the Ceramicrete binder mixture for stabilization of Hg, and dense and hard ceramic waste forms were produced. Just before solidification, TCLP results were obtained on small aliquots of the mixing slurry that was separated and allowed to set. Mercury levels in the leachate were found to be 0.05 /rg/1, well below the LfTS limit of 0.025 mg/1. The entire waste was treated, removed from the inventory, and sent to the Radioactive Waste Management Complex at the Idaho National Engineering and Environmental Laboratory for disposal. 

Compared with fission reactors, operation of fusion reactors is more complicated because of the high ignition temperatures, the necessity to confine the plasma, and problems with the construction materials. On the other hand, the radioactive inventory of fusion reactors is appreciably smaller. Fission products are not formed and actinides are absent. The radioactivity in fission reactors is given by the tritium and the activation products produced in the construction materials. This simplifies the waste problems considerably. Development of thermonuclear reactors based on the D-D reaction would reduce the radioactive inventory even further, because T would not be needed. The fact that the energy produced by fusion of the D atoms contained in 1 litre of water corresponds to the energy obtained by burning 120 kg coal is very attractive. 

The fast-spectrum reactors with full recycle of actinides would be designed with on-site spent fuel reprocessing and fuel fabrication to minimize the on-site inventory of long-lived radioactive waste. Modern robotic equipment can be used for reactor refueling and for fuel reprocessing. The spent fuel reprocessing and fuel fabrication facilities must be developed to close the nuclear fuel cycle and use all the energy available in natural uranium. 

DOE. 1987. Integrated data base for 1987. Spent fuel and radioactive waste inventories, projections and characteristics. DOE/RW-0006, rev. 3. U.S. Dept, of Energy. 

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