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Rail Transportation Casks. Testing of Transportation Casks. To be certified, transportation casks must demonstrate that they must remain airtight following A 30-foot drop onto an unyielding surface A 40-inch drop onto a 6-inch diameter steel rod Exposure to a 1000 ºC fire for 30 minutes
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Testing of Transportation Casks • To be certified, transportation casks must demonstrate that they must remain airtight following • A 30-foot drop onto an unyielding surface • A 40-inch drop onto a 6-inch diameter steel rod • Exposure to a 1000 ºC fire for 30 minutes • Immersion in 3 feet of water • Additional, more severe, testing has been done • Crash of a flatbed truck loaded with a cask into a 700-ton concrete wall at 80 mph • Broadside crash of a 120-ton locomotive traveling at 80 mph • Crash of a locomotive at 100 mph (U.K.) • Drop onto hard soil (similar to concrete) from a height of 2,000 feet • Fire and explosion involving fuel tanks (Germany)
Yucca Mountain Surface Facility Portals South Portal North Portal
Surface (Preclosure) Facility Design • Surface facility design provides maximum flexibility in the development of a simple, clean, safe, primarily canister-based repository • Based on the use of modular waste handling facilities and processes – expansion as needed • Incorporates commercial waste handling experience • Can receive by truck and standard rail • Can handle multiple forms of wastes • Can accommodate multiple sizes of transportation, aging and disposal (TAD) canisters • TAD canisters containing the spent fuel are loaded into the transportation casks • TAD canisters would require less handling than individual spent nuclear fuel assemblies at the repository
Preparing Waste for Emplacement • Cask enters the facility, impact limiters and lid are removed, and the cask is raised upright by crane • Cask loaded onto a cask transfer trolley and moved to the shielded transfer cell • Another crane lifts the TAD canister out and raises it into a shielded bell • Shielded bell moves to the canister to another transfer cell • Canister is lowered by crane into the waste package • Waste package is what the canister is stored in when emplaced in the mountain • Waste package is transferred to the Transport and Emplacement Vehicle (TEV)
Transfer of Canister to Waste Package casktransfer.wmv
Transfer of the Waste Package to the TEV WPtransfertoTEV.wmv
Emplacement Operations • TEV moves waste package from the surface facility into the mountain • Emplacement tunnel is selected beforehand to limit the total decay heat generated in the tunnel • Tunnel decay heat loading is tracked continuously • TEV deposits the waste package once it has arrived at its final destination • TEV returns to the surface
Safety of Preclosure Operations • Preclosure operations include all preparation and emplacement activities • Expected to last 50 years (until all tunnels are filled) • Safety features • Robust construction (3 to 4-foot thick reinforced concrete walls) can withstand the most severe postulated earthquake • Filtered ventilation system to prevent release to environment in the event of an accident • Automatic fire suppression system • Remote operations to limit need for human action • Extensive shielding provided when human involvement is anticipated • Safety analyses show that potential public and worker radiation exposure from preclosure operations is well below NRC safety limits
Postclosure • Postclosure begins when the repository has been fully loaded and sealed for long-term storage • Storage is in 42-miles of 18-foot diameter tunnels • Parallel tunnels located 250 feet apart • Tunnels are 1,000 feet below the surface and 1,000 feet above the water table • Natural and manmade features ensure safety and environmental protection during storage
Total System Performance Assessment • TSPA is a computer tool that analyzes performance of the repository following closure • Includes computer models for all phenomena that could lead to a release of radionuclides • Based on accepted chemical and physical principles • Benchmarked against data collected during site assessment • TSPA is used to evaluate repository performance over hundreds of thousands of years • Because the period of interest is so long, extremely rare events must be analyzed • Severe earthquakes, volcanic activity, meteor strikes, etc. • TSPA results show human exposures or ground water contamination at least a factor of 10 smaller than safety standards
Status and Future of the Project • License application for the Yucca Mountain repository submitted to the NRC on June 2nd • NRC has 3 years to complete their evaluation and decide whether to issue a construction permit • Government funding levels will be an important factor in determining when the repository opens • Most optimistic estimate is 2017 for receipt of first waste • Politics will play a key role
Politics of the Yucca Mountain Project • NIMBY – Not in my backyard • States with stored nuclear waste want it disposed of • Nevada objects to being the nuclear “dump” • Some have concerns over waste transport • People are reluctant to believe the government regardless of the scientific support • Politicians tend to play on these emotions • Nowhere is this more evident than in Nevada • A “battleground” state
Cartoons Illustrating Safety Concerns • Cartoonists play on emotions • No need to be scientifically accurate • Probably very effective with the average person
Where do the candidates stand? • Obama expressed his opinion in a letter to Senators Reid and Boxer • Nuclear power remains an important source of energy • Objected to Congress abandoning scientific consideration of alternatives and selecting Yucca Mountain • Indicated that Yucca Mountain is not a good choice • Nevadans oppose Yucca Mountain • Won’t be operated for at least 10 more years • Uncertain safety of transport and long-term storage • Time to abandon Yucca Mountain and pursue alternatives • Selection based on sound science and respect for state’s sovereignty
Where do the candidates stand? • McCain’s opinion has been expressed in interviews over the years • Nuclear power is an important source of energy for our future and more reactors are needed • Supports Yucca Mountain as the best alternative for long-term storage • Yucca Mountain should be built if it meets all Federal requirements for protecting human health and the environment • Not a problem of technology but political will