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Yucca Mountain Project. Alparslan Gurbuz. Types of Waste To Be Stored. SNF - spent nuclear fuel from nuclear reactors that hasn’t been reprocessed HLW - high-level radioactive waste formed when reprocessing spent fuel Other radioactive waste:
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Yucca Mountain Project Alparslan Gurbuz
Types of Waste To Be Stored • SNF - spent nuclear fuel from nuclear reactors that hasn’t been reprocessed • HLW - high-level radioactive waste formed when reprocessing spent fuel • Other radioactive waste: • greater-than-class-C waste - highly radioactive low-level waste • Plutonium-239 resulting from the dismantlement of nuclear weapons SNF Cooling Pool http://www.nrc.gov/waste/spent-fuel-storage/pools.html 90%: Commercial Nuclear Power Plants 10%: Government Defense Programs http://www.epa.gov/radiation/yucca/about.htm Half-lives range from 30 years, such as Cesium, to 24,000 years, such as Plutonium
The Formation of SNF Nuclear Waste:Nuclear Fission • A Uranium atom absorbs a neutron. • The atom becomes unstable and divides. • The division forms two smaller atoms, and releases up to three neutrons along with energy. • The energy is absorbed by water as heat and used to generate electricity. • The neutrons repeat this process of nuclear fission by splitting up other Uranium atoms, forming a chain of reaction. The controlled process is a self-sustaining chain of reaction.
Fission fragments - the divided atoms that can no longer provide economically enough energy and continue the chain of reaction (waste) Every three to four years, the fuel rods that hold Uranium pellets are removed after about 25% of the atoms have undergone nuclear fission. They are intensely radioactive because they still emit considerable amounts of energy as they decay. They are then removed, cooled in pools, and placed in temporary concrete tanks with steel outlines. The Problem of Waste www.chm.bris.ac.uk/ motm/uf6/uf6c.htm US Department Of Energy Transportation FAQs
To contain the radiation, the material must be held in impenetrable containers such as the nuclear reactors’ tanks during the fission process and afterwards when it is in the form of waste. Since these pools are filling up, the waste must be transported to a government facility that provides permanent underground storage for radioactive waste. The Problem of Waste(cont’d) www.chm.bris.ac.uk/ motm/uf6/uf6c.htm www.yuccamountain.org/transport.htm
Yucca Mountain Timeline • 1952 Atomic Energy Act- allowed private ownership of nuclear materials, but despite restrictions could control to ensure public health and safety, which includes final disposal • 1982 Nuclear Waste Policy Act- Began a policy for a permanent geological SNF and HLW repository by the Office of Civilian Radioactive Waste Management of DOE • 1987 Amended NWPA- Directed DOE to study the Yucca Mountain environment for the repository site • 1992 Energy Policy Act- Assigned Environmental Protection Agency to set standards for the Yucca Mountain site • 2002 July- The president and Congress approved the Yucca Mountain site for radioactive waste disposal • ? 2004- Nuclear Regulatory Committee may grant the license needed to dispose the nuclear waste at the first radioactive waste repository site of the US • ? 2010- Earliest expected year to commence waste disposal
EPA Safety Standards “... [EPA shall] promulgate, by rule, public health and safety standards for protection of the public from releases of radioactive materials stored or disposed of in the repository at the Yucca Mountain site. Such standards shall prescribe the maximum annual effective dose equivalent to individual members of the public from releases to the accessible environment from radioactive materials stored or disposed of in the repository.” Energy Policy Act of 1992 (Public Law 102-486)
Standards by EPA Maximum Annual Radiation Dose • 15 millirem during pre-closure to someone in vicinity • 15 millirem during post-closure to someone in vicinity (to repository site) • 4.3% of natural average radiation dose • Same dose as Waste Isolation Pilot Plant of New Mexico • Considered harmless • 4 millirem from groundwater radionuclides • 5 rem estimated radiation exposure to Yucca Mountain site workers Average annual radiation dose from natural sources: 350±50 millirem Recommendation by the Secretary of Energy 6.1.2 NRC Guidelines 40 CFR
“6. Is Yucca Mountain Scientifically and Technically Suitable for Development of a Repository? “The Department of Energy … concludes, as set out in 10 CFR part 963, that Yucca Mountain is ‘likely’ to meet the applicable radiation standards and thus to protect the health and safety of the public, including those living in the immediate vicinity now and thousands of years from now.” (Underline emphasis on “likely”) Recommendation by the Secretary of Energy Regarding the Suitability of the Yucca Mountain Site for a Repository Under the Nuclear Waste Policy Act of 1982 February 2002
The Repository Solution: Yucca Mountain “Proceeding with the repository program is necessary to protect public safety, health, and the Nation's security because successful completion of this project would isolate in a geologic repository at a remote location highly radioactive materials now scattered throughout the Nation. In addition, the geologic repository would support our national security through disposal of nuclear waste from our defense facilities. “A deep geologic repository, such as Yucca Mountain, is important for our national security and our energy future. Nuclear energy is the second largest source of U.S. electricity generation and must remain a major component of our national energy policy in the years to come.” President Bush, February 15, 2002, Presidential Letter to Congress
Location • Repository: • 300 meters above the ground water • 300 meters below the peak of the mountain
Why the Yucca Mountain site? • Federally owned land • Remote; smaller impact • Within boundaries of Department of Energy Nuclear Test Site in Nye County • Low resource value • Ideally cheaper to dispose the waste in the Yucca site than at current locations throughout the nation Ron Oden, J. Kurowski, and Stephen Reich. A Closer Look at Yucca Mountain
Shipment Routes • Currently stored at 131 commercial reactor and Energy Department sites • Over a period of 30 years, the 77,000 tons of radioactive waste will be transported • Every shipment will cover an average distance of 2000 miles • The waste will pass through 734 counties, coming into a 3 mile proximity of 50 million people • It will move through many large metropolitan cities ranging from a daily basis to every 7 hours (Salt Lake City) http://www.counterpunch.org/krieger0904.html
Transportation Routes Throughout The US http://www.state.nv.us/nucwaste/maps2002/roadrail/index.htm
Waste Casks The nuclear waste will be stored within cask containers. For transportation, the waste will be contained in transportation casks and moved on trucks, trains, and barges. Transportation Cask • Basic Structure: • Basket holding the waste located inside a cylindrical canister • Impact limiters – shock absorbing caps at each of the cylindrical canisters www.yuccamountainfacts.org/ htmltonuke.php?filnavn=transportation.html • The transportation casks are designed to sustain containment efficiency after undergoing the following successive tests: • “a drop from 30 ft onto an unyielding surface; • a drop from 6 ft onto a spike; • a 30 minute fire at 1425°F; and • a 30 minute submersion in 3 ft of water” Storage Cask Nuclear Regulatory Committee Cask Safety Guidelines
Internal Design Ron Oden, J. Kurowski, and Stephen Reich. A Closer Look at Yucca Mountain
Maximum of 10 millirem per hour at 6 ft from cask Cask truck and train drivers Neighboring cars during traffic jams Children (can develop cancers after only 1/10th of the standard cancer causing exposure to radiation) Cask durability tests Performed using computer simulations Accident/Disaster Analysis Performed using computer simulations with data dating back to 1980s Transportation safety guidelines are from 1970s, do not take terrorist attacks into consideration “We cannot easily de-couple the environmental from safety considerations of transportation and try to study them in laboratory isolation; there are interactive effects among them.” Najmedin Meshkati, Ph.D. February 23, 2002. Safety, Security and Environmental Research Needs for Transporting Nation’s High-Level Nuclear Waste to Yucca Mountain Transportation Cask Safety http://www.yuccamountainfacts.org/htmltonuke.php?filnavn=transportation.html
Transportation Compatibility “… [the Yucca Mountain site] is affected by unique local conditions that increase both the radiological risks and perceived risks of nuclear waste transportation. “DOE‘s 1986 comparative analysis showed that selection of Yucca Mountain would result in … the highest projected number of transportation accident injuries and fatalities.” Robert J. Halstead, Transportation Advisor to the State of Nevada Agency for Nuclear Projects. http://www.state.nv.us/nucwaste/news2001/nn11099.htm
Casualty Estimation Comparisons • One accident expected for every 300 shipments • Estimated $6 billion per serious accident • Casualties per year from a severe accident (1.3’ diameter hole in transportation cask) range from 80 (DOE) to between 450 and 2900 (State of Nevada) • Untrained and unprepared health facilities along the routes in dealing with mass exposure to radioactive waste • DOE uses favorable numbers: • Radiation Potency Number is outdated, the required radiation dose to develop fatal cancers is half that of National Academy of Sciences • Assumes waste to have cooled for 15 years before transportation, but will only have cooled for 5 years • Estimations based on lowest emission of Cesium gas during accident *Proximity to schools and higher vulnerability to children not considered
Transportation Accident Effects “…if there is an accident (or foul play) resulting in the release of a hazardous substance from a cargo train, then the train operators are the first layer of people whose safety and health are impacted. The next immediate concern is for the local affected public, “down wind” communities, as well as the short and long-term environmental effects of such release on water, soil and air. Therefore, as long as the transportation of nuclear waste and its potential release is concerned, the safety (including security) and environmental considerations are mutually reinforcing areas and are two sides of a coin.” Najmedin Meshkati, Ph.D. Safety, Security and Environmental Research Needs for Transporting Nation’s High-Level Nuclear Waste to Yucca Mountain.February 23, 2002.
Yucca Mountain Site Characterization • Unknown possible climate changes • Underground water table • Crystals are possible indication of “intermittent upwelling of groundwater” • Thousands of years later, cladding could be corroded to let the water absorb radionuclides from the waste • Only water source to residents of Amargosa Valley • Water source to largest Nevada dairy farm that supplies milk to 30 mil people on the west coast • Active magma pocket below the mountain • Earthquakes • 3rd most seismically active region of US • More than 600 earthquakes in past 25 years • Last earthquake on July 14, 2002, magnitude of 4.4 • Volcanic history http://www.counterpunch.org/krieger0904.html http://tms.physics.lsa.umich.edu/214/other/news/080799sci-yucca-mountain.html
Protest The half-life of Plutonium is 24,000 years, meaning it will emit hazardous radiation for the next 240,000 years.
Political Cartoon Disposing the waste seems cheaper and safe now, but the effects will prove otherwise.
References • http://www.nrc.gov/waste/spent-fuel-storage/pools.html • http://www.epa.gov/radiation/yucca/about.htm • US Department Of Energy Transportation FAQs • http://www.chm.bris.ac.uk/motm/uf6/uf6c.htm • http://www.yuccamountain.org/transport.htm • Energy Policy Act of 1992 (Public Law 102-486) • Recommendation by the Secretary of EnergyRegarding the Suitability of the Yucca Mountain Sitefor a Repository Under the Nuclear Waste Policy Act of 1982. February 2002 • President Bush.Presidential Letter to Congress. February 15, 2002 • Ron Oden, J. Kurowski, and Stephen Reich. A Closer Look at Yucca Mountain • http://www.counterpunch.org/krieger0904.html
References cont’d • http://www.state.nv.us/nucwaste/maps2002/roadrail/index.htm • http://www.yuccamountainfacts.org/htmltonuke.php?filnavn=transportation.html • Nuclear Regulatory Committee Cask Safety Guidelines • http://www.yuccamountainfacts.org/htmltonuke.php?filnavn=transportation.html • Najmedin Meshkati, Ph.D. February 23, 2002. Safety, Security and Environmental Research Needs for Transporting Nation’s High-Level Nuclear Waste to Yucca Mountain • Robert J. Halstead, Transportation Advisor to the State of Nevada Agency for Nuclear Projects. • http://www.state.nv.us/nucwaste/news2001/nn11099.htm • http://tms.physics.lsa.umich.edu/214/other/news/080799sci-yucca-mountain.html