Presentation on theme: "Chapter 7. Nuclear Waste 1.Nuclear Waste Disposal: Amounts of Waste Categories of Nuclear Waste Wastes from Commercial Reactors Hazard Measures for Nuclear."— Presentation transcript:
Chapter 7. Nuclear Waste 1.Nuclear Waste Disposal: Amounts of Waste Categories of Nuclear Waste Wastes from Commercial Reactors Hazard Measures for Nuclear Wastes 2. Storage and Disposal of Nuclear Wastes Stages in Waste Handling Deep Geologic Disposal Alternatives to Deep Geologic Disposal Worldwide Status of Nuclear Waste Disposal Plans
城市放射性废物管理办法 IAEA Safety Standards: Geological disposal of radioactive waste
Types of Waste High-Level Waste The most dangerous radioactive waste Spent fuel comes from nuclear reactors (52,000 tons) liquid and solid waste from plutonium production (91 million gallons). About 70 percent of the available storage space is now filled with used fuel assemblies at Turkey Point.
Types of Waste Transuranic Waste –Includes clothing, tools, and other materials contaminated with plutonium, neptunium, and other man-made elements heavier than uranium. (11.3 million cubic feet)
Types of Waste Low and Mixed Low-Level Waste –Includes radioactive and hazardous wastes from hospitals, research institutions, and decommissioned power plants (472 million cubic feet) –Turkey Point produced annually on average about 2,500 cubic feet of low-level waste. This amount of waste could be contained within an area about the size of a 30'x30' room.
Uranium Mill Tailings Residues left from the extraction of uranium ore (265 million tons). Types of Waste
Slide 1 Nuclear Waste: Where it comes from and why it happens. Elena Berman
What? Nuclear waste is waste coming from trying to make energy. Once this energy is made, though, it lets of some waste. The amount of it is pretty small, but is also radioactive. This can be bad for the human body as well as for the environment. There are three kinds: alpha, beta, and gamma. The alpha rays cant get under your skin, and can be blocked, but it is dangerous to get into your lungs. Beta rays can enter your skin but it can also be blocked by something, like a sheet of tin foil, though you would look silly walking around in a tin foil suit. Gamma rays can go straight through you, so you would need to be protected by either a lot of concrete, or a meter of water, which you obviously couldn’t wear or use on your body. These things are natural, but they are still classified as waste!
Where? Nuclear waste comes from the nuclear fuel cycle. This is the cycle where the nuclear material is turned into electricity. Plants that do this are mainly where all of that comes from. These plants only let off a small amount of waste, really, but it makes a huge impact since its all so radioactive, so it needs to be contained.
Where? (cont.) Some places have been contaminated by nuclear waste, but not in the same way as explained in the previous slide. Something that you have probably heard of, Chernobyl, was a place that had a huge problem because there was an explosion and fire in a nuclear power plant, and all around it places and people were being contaminated by all the waste that was being sent around. It was considered on of the worst accidents in a nuclear power plant that had ever happened. It spread through Ukraine (where the plant was) and Europe.
Why? Now, a question you might have is why people make nuclear energy if they know there can be such awful side effects? The reason that people make nuclear energy is because even though the waste is radioactive, it still lets off only a small amount, so it isnt having so much pollution and everything as other places do.
Nuclear Waste There four different kinds of waste: High- level (spent fuel and plutonium waste), transuranic (contaminated tools and clothes), low and mixed low-level (hazardous waste from hospitals), and uranium mill tailings. In the US there is approximately 91 million gallons of high-level waste, 11.3 million cubic feet of transuranic waste, 472 million cubic feet of low and mixed low level waste, and 265 million tons of uranium tailings. Source: Michael E. Long “Half-life: The Leathal Legacy of America’s Nuclear Waste” National Geographic July 2002.
Storage Many facilities store their own waste on site, but they are quickly running out of space. Other sites are in the process of being cleaned, but there is no place to store the waste. Part of the problem is the half-life. Half-life is how long it takes for an unstable element to decay half way. Uranium 238 takes 4.5 billion years. Typically, after ten “half-lives” the element is considered safe. Nuclear waste lacks permanent safe storage. Temporary storage is being proposed for the Skull Valley Goshute Indian reservation, and permanent storage may be in Yucca mountain. Mean while waste and tailings are pilling up. Source: Michael E. Long “Half-life: The Leathal Legacy of America’s Nuclear Waste” National Geographic July 2002.
Skull Valley Goshutes According to the Skull Valley Goshute Indian website the Goshute Indians in Utah recently made an agreement with a private utility to temporarily store 40,000 metric tons of spent nuclear fuel. The Goshute reservation is 18,000 acres, and already surrounded by other polluting industries. To the south of the reservation is the Dougway Proving Grounds—a government chemical and biological weapons testing site. Also to the south is the Intermountain Power Project, which mainly makes coal-fired electricity for California. To the east is a government depository of nerve gas, and to the northeast is a low-level radioactive disposal site and toxic waste incinerator. Finally, in the north is a magnesium production plant. On the Skull Valley Goshute website it is stated that since the reservation is already surrounded by hazardous facilities, and after careful consideration and consultation with the government, scientists, and corporations, they have entered into this agreement. Source: http://www.skullvalleygoshutes.org/http://www.skullvalleygoshutes.org/
Moab, Utah This is a picture of a ten-million ton pile of uranium tailings. The pile is right next to the Colorado River, and leaks ammonia into it threatening the fish. The owners of the pile when bankrupt, so no the citizens of Moab are waiting for the Department of Energy to clean it up. The clean up will cost an estimated 64 million dollars. Source: http://magma.nationalgeographic.com/ngm/0207/feature1/zoom3.htmlhttp://magma.nationalgeographic.com/ngm/0207/feature1/zoom3.html
Yucca Mountain Yucca Mountain located in southern Nevada. Although this location has not been built yet, the plan is to have the waste buried deep in the mountain. Waste would be transported from all over the country in specially design railroad cars and truck trailers. The waste would then be repackaged for final burial. This plan is highly controversial. Source: http://magma.nationalgeographic.com/ngm/0207/feature1/zoom3.htmlhttp://magma.nationalgeographic.com/ngm/0207/feature1/zoom3.html Picture: www.ocrwm.doe.govwww.ocrwm.doe.gov
Impacts Radioactive waste is highly dangerous to humans and the environment. Because the waste will remain radioactive for so long, it will remain to be a threat for thousands of years.
Conclusion Overall, nuclear energy disproportionately effects rural communities and the communities near nuclear facilities. Uranium mining and bombing are particularly detrimental to the environment. Further, the effects of radiation (cancer, illness, and death) are significant. If you find yourself in a situation where you are being exposed to radiation, shield yourself from the blast, and then move as far away from the detonation area as possible (otherwise remain indoors). Source: Ready.gov
Mining Uranium ore is usually located aerially; core samples are then drilled and analyzed by geologists. The uranium ore is extracted by means of drilling and blasting. Mines can be in either open pits or underground. Uranium concentrations are a small percentage of the rock that is mined, so tons of tailings waste are generated by the mining process. Sources: http://www.anawa.org.au/mining/index.html and http://www.energyres.com.au/ranger/mill_diagram.pdf and http://www.world- nuclear.org/education/mining.htmhttp://www.anawa.org.au/mining/index.html http://www.energyres.com.au/ranger/mill_diagram.pdfhttp://www.world- nuclear.org/education/mining.htm
Production in 2000 Canada 10,682 Australia 7,578 Niger 2,895 Namibia 2,714 Uzbekistan 2,350 Russia (est) 2,000 Kazakhstan 1,752 USA 1,456 South Africa 878 China (est) 500 Ukraine (est) 500 Czech Republic 500 India (est) 200 France 319 others 422 Total world 34,746 companytonnes U Cameco7218 Cogema6643 WMC3693 ERA3564 Navoi2400 Rossing2239 KazAtomProm2018 Priargunsky2000 Source: http://www.world-nuclear.org/search/index.htmhttp://www.world-nuclear.org/search/index.htm
Yucca Mountain Project: Nuclear Fuel and High Level Waste Repository Much more secure repository than leaving high level waste at 60 reactor sites around the country. On old atomic bomb testing base, inside a mountain. The storage is above the water table. The Yucca Mountain site would be 60% filled by present waste. US has legal commitment to the reactor industry. Site has been studied extensively by scientists for over 20 years. Will store waste during its 10,000 year decay time. Questions of how to deflect dripping water around and under the storage vessels. Questions of radioactive decay weakening storage containers. A solution would be to build containers that can be opened and reincased, or to which surrounded casings could be added.
By Oriel Wilson Race Poverty and the Urban Environment Professor Raquel R. Pinderhughes Urban Studies Program San Francisco State University Spring 2003 *Public has permission to use the material herein, but only if author, course, university and professor are credited. Dennis Silverman, U C Irvine Lindsey Garst Jay Nargundkar Jonah Richmond
Waste Disposal Yucca mountain Use breeder reactors instead Alternative storage site
Yucca Mountain The Future of Nuclear Waste Storage
Current Waste Disposal At this time, radioactive wastes are being stored at the Department of Energy ’ s facilities around the country High level wastes are stored in underground carbon or stainless steel tanks Spent nuclear fuel is put in above- ground dry storage facilities and in water-filled pools
Yucca Mountain Storage sites becoming full, waste may be transported to Yucca Mountain Located on government land, about 100 miles northwest of Las Vegas in the Nevada desert It is a 6 mile long, 1,200-foot high flat-topped volcanic ridge Will be able to house 70,000 tons of radioactive material
Problems with Yucca Mountain The nuclear waste currently sitting around is enough to fill the repository At the earliest, the repository will be open in 2010, which seems unlikely NRC has found 293 technical issues with the repository that must be fixed Danger to the public with the transportation of the waste to yucca mountain
Possible health risks to those living near Yucca Mountain Eventual corrosion of the metal barrels which the waste is stored in Located in an earthquake region and contains many interconnected faults and fractures These could move groundwater and any escaping radioactive material through the repository to the aquifer below and then to the outside environment Still More Problems
Oops! At right is a map of the Yucca Mountain site The area within the dotted line is the burial site Two faults run directly through the site
Current Situation The Government maintains that Yucca Mountain will open on time, in 2010 Those in the nuclear energy industry put that date closer to 2015 or not at all It has been suggested that the construction of concrete and steel cask fields will add additional waste storage space to nuclear plants This would allow several additional decades for the government to put together a permanent nuclear waste storage facility