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High Flux Beam Reactor Transportation
The Department of Energy (DOE) and its predecessor agencies have a successful 50-year history of safely transporting radioactive materials. As the DOE Office of Environmental Management continues its mission, transportation will continue to play a key role in the cleanup efforts. It is Brookhaven National Laboratory's (BNL's) policy to integrate safety stewardship into all facets of the Laboratory's operations, including packaging and transportation of hazardous and radioactive materials. BNL manages hazardous materials transportation in a manner that protects employees, the public and the environment. Employees and the public are protected from unnecessary exposure to hazardous material during transport. Facilities, equipment, and the environment are protected from contamination. Compliance with applicable regulatory and contractual requirement is assured and exposure to hazardous materials is kept As Low As Reasonably Achievable (ALARA). Once a clean-up remedy for the High Flux Beam Reactor (HFBR) is accepted, BNL will take action to reduce the radioactive materials inventory (curie content) of the HFBR complex. The activated reactor control rod blades (CRBs, right) and beam plugs (see figure below) will be removed over the next year and disposed of as low-level radioactive waste. This waste will be sent to DOE's Nevada Test Site for disposal. The blades, which contain approximately 22,000 curies of radioactive material, were used to absorb the neutrons that controlled the fission reaction inside the reactor vessel. There are 16 CRBs inside the HFBR reactor vessel, including eight main and eight auxiliary CRBs. The main CRBs are constructed of two L-shaped blades of europium and dysprosium, clad by stainless steel. The blades are each approximately 3 inches wide by 40.25 inches in length. The eight auxiliary CRBs are similarly constructed, but are only 12.5 inches long. There are nine cylindrical steel beam plus of varying sizes that were used during experimental processes to enable researchers to irradiate samples. The beam plugs contain 500 curies of contamination. Together, the CRBs and beam plugs contain 35 percent of the current HFBR radioactive materials inventory in the HFBR complex. The predominant radionuclide found in the CRBs and beam plugs is cobalt-60.
The CRBs and beam plugs will be transported using Department of Transportation-approved Type A and Type B casks. The casks are constructed from steel and encased with lead shielding. The undergo rigorous testing, and are only certified after they survive a sequence of impact, crush, puncture, fire, and immersion tests designed to replicate transport accident conditions. Type B casks are put through a series of ten tests under normal conditions of transport and six tests under hypothetical accident conditions - including a 30-foot drop-test - to ensure their integrity. Three Type B casks will be used to transport the CRBs and several beam plugs. These casks will be loaded and closed underwater to minimize exposure and to control contamination. The water will then be removed from the casks and they will be placed onto specifically designed flatbed trailers. Two Type A casks will be used for the remaining beam plugs. These casks will be loaded and closed using remote equipment to minimize exposure within the HFBR confinement building. They will also be loaded onto specifically designed flatbed trailers (shown at top of page). A total of five shipments are expected to
occur in 2008. Radioactive dose limits for BNL shipments are typically
lower than allowed under federal regulations. The dose limits of the
HFBR shipments are expected to be even lower. The maximum radiation
dose for these shipments at a distance of six feet for one hour will be well
below the recommended DOE National Transportation limit for transporting
hazardous materials. To learn more, see
Last Modified: May 22, 2009 |
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