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Nuclear Waste. By: Suhani Ray, Sunita Prasla, Sibnish Ali, Rachael Milne, Jessica Chou. introduction. What exactly is nuclear (radioactive) waste? So can you just throw the waste into any trash place? 3. Electric power>>(rods) heat>>steam>>generator>>electricity. Suhani Ray. Suhani Ray.
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Nuclear Waste By: Suhani Ray, Sunita Prasla, Sibnish Ali, Rachael Milne, Jessica Chou
introduction • What exactly is nuclear (radioactive) waste? • So can you just throw the waste into any trash place? • 3. Electric power>>(rods) heat>>steam>>generator>>electricity Suhani Ray
Radioactive waste has different levels of waste • High level- “Waste from power plants that is highly radioactive is called high-level waste.” • Low level- “Waste that is only slightly radioactive and gives off small amounts of radiation is called low-level waste.” • Low level special sites = isolated environment Suhani Ray
1. What sources account for the accumulation of nuclear waste? Which ones contribute the most waste? • Generated from hospitals, laboratories, and industry • Includes clothing, tools, rags, papers and filters • Worldwide, it is 90% of volume of the waste, but is only 1% of the radioactivity. Rachel Milne
Intermediate-level Waste • Involves, chemical sludge's and reactor components, processing and enrichment plants, from nuclear weapons facilities, and from nuclear power plants ,also it is has contaminated materials from reactor decommissioning. • It makes up 7% of the volume of the waste, and 4% of the radioactive of the whole Rachel Milne
High-level Waste • Comes from spent fuel from nuclear reactors. • It Contains the highly-radioactive fission products and also some elements with long-lived radioactivity. • It is only 3% f the volume of waste, but it holds 95% of the radioactivity. Rachel Milne
2. Can nuclear waste be made safe? • Nuclear waste can be made safe in a way by making it stable and no because there are solutions to it by placing the waste 500 meters below setting below the surface known as geological disposal. Another solution is to reduce the mass of long-lived, high-level waste which means partitioning and transmutation. Sibnish Ali
3. What are the Short Term Solution? • Currently, after a period of temporary storage when the most radioactive product have had the chance to decay high level waste from the spent nuclear fuel is incased in a borosilicate glass and sealed in stainless steel drums. Suhani Ray
4. Are there presently any long-term solutions to storage of nuclear waste? • At the moment there are three kinds of options being considered for permanent nuclear waste storage. • MOX fuel burning method (Mixed Oxide) • Verification Method • Subductive waste Disposal Method Rachel Milne
MOX fuel burning method (Mixed Oxide) • Method in which plutonium is mixed with uranium. • When plutonium burns, nuclear fission occurs. • More of the plutonium is burning, which produces more energy and faster. • Although it produces more plutonium, it is less dangerous in the environment. • So…. The amount of plutonium is reduced, leaving the remaining, less usable for weapons and easy to dispose. Rachel Milne
Verification Method • This method involves the mixing of weapons-grade plutonium and radioactive waste from civilian reactors. • It is placed in borosilicate glass logs. • The logs will be dug in deep boreholes. • Plutonium could be efficiently encased and isolated to allow the decaying progress to occur. • But it is possible for a leakage to occur, or it could be mined in the future. Rachel Milne
Subductive Waste Disposal Method • This method is the placement of the waste in a subducting tectonic plate. • The plate reabsorbs, and along with it, the waste. It will be dispersed into the mantle. • Using this method would prevent any radioactive or nuclear waste from mixing with water , stop access for the production of nuclear weapons, remove the waste from harmful positions to the environment, and be safe from any marine life in the world. Rachel Milne
5. Proposed solution and controversy of Yucca Mountain in Nevada. Problems: -U.S. needs a repository site for high level waste -Companies say storage areas are almost full Jessica Chou
5. Proposed solution and controversy of Yucca Mountain in Nevada. Proposed Solution: -1987 Department of Energy chooses Yucca Mountain northwest of Las Vegas, Nevada May 16, 2006 The Senate Energy and Natural Resources Committee hearing on the Yucca Mountain nuclear waste project Jessica Chou
5. Proposed solution and controversy of Yucca Mountain in Nevada. Controversy: -Costs a lot: $57.5 billion -Takes to long: about 30 years -Target for Terrorists: nuclear waste on the road can be targeted by terrorists - Will be full capacity: by about 2020 shipment of mixed nuclear waste from rom a federal lab in Idaho Jessica Chou
5. Proposed solution and controversy of Yucca Mountain in Nevada. Controversy: • Economical objection: might slow business and tourism • Scientific objection: earthquakes and volcanic eruption may occur. Water can leak into storage room - Political opposition: Lawsuits by the State of Nevada and other groups Jessica Chou
6. What are the different levels of nuclear waste and what dangers does each level poses? • Low Level Waste • High Level Waste Sunita Prasla
Low Level Waste • Low-level waste includes items that have become contaminated with radioactive material or have become radioactive through exposure to neutron radiation. • The radioactivity can range from just above background levels found in nature to very highly radioactive in certain cases such as parts from inside the reactor vessel in a nuclear power plant. Sunita Prasla
High Level Waste • High-level radioactive wastes are the highly radioactive materials produced as a byproduct of the reactions that occur inside nuclear reactors. High-level wastes take one of two forms: -Spent (used) reactor fuel when it is accepted for disposal -Waste materials remaining after spent fuel is reprocessed Sunita Prasla
7. What elements are involved in #6 and how long do they remain radioactive? • Short Term Radioactive -Uranium-235, Cesium-137, Strontium-90 • Long Term Radioactive -Plutonium- 239, Americium- 243 Sunita Prasla
8. Effects of nuclear waste on the environment. Does it pose an immediate threat to the general public? Effect on Environment: • Low level waste in concrete encased in steel drums has been dumped in the Atlantic Ocean. If drums leak liquids, fish nearby become irradiated - Metal drums of low level waste at some sites have leaked radioactive fluids into the soil and groundwater 08/26/1997 Japan's nuclear power program said it is investigating whether radioactive liquid has seeped into groundwater from the rusting drums in the concrete pits Jessica Chou
8. Effects of nuclear waste on the environment. Does it pose an immediate threat to the general public? Immediate threat to general public? - No not an immediate threat because waste is kept secure from the public but in the future irradiated soil, groundwater, and animals may affect humans - Waste underground would protect it from being exposed to environmental factors above ground that could cause the waste to break down into radioactive particles that could be scattered by air or water. Jessica Chou
9. Countries with the most Nuclear Waste 1. United States 2. Canada 3. France 4. Japan 5. United Kingdom 6. Germany 7. South Korea 8. Sweden 9. Spain 10. Belgium Storage pond for spent fuel at UK reprocessing plant Jessica Chou
9. Countries with the most Nuclear Waste Jessica Chou
9. Countries with the Most Waste • Canada • United Kingdom • Sweden • France • Finland • Belgium • Switzerland • United States • Japan • Germany Jessica Chou
10. Discuss what impact the nuclear age has had on civilization? • It started in 1950 and there was a storage problem but United State Atoms for Peace Initiative take the residue of the fuel and dispose of it. Sibnish Ali
Conclusion • High level = highly radioactive • Low level = low radioactivity • When did nuclear waste start? • Fission • http://gtm-media.discoveryeducation.com/videos/pmp/videos/wm/1MB/60290-HAVTC_1Mb.wmv Suhani Ray