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Depleted Uranium Survey and Removal in Kuwait J.I. Cehn*, PIKA International, Inc.
Abstract: An area of a U.S. Army camp in the Kuwaiti desert was used for practice firing of depleted uranium projectiles. The 44 acre area was littered with projectile fragments. A project was conceived and carried out to locate these fragments and remove them, thus clearing the area of contamination. Sand mounds containing most of the fragments were brought down and layered into lifts, so they could be surveyed, and the uranium detected and removed. Teams of technicians and laborers were employed in this work. Training of non-English speaking laborers for radiation work was a special challenge.
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Uncertainty Analysis for Surface Water Sampling of Tritium at the Savannah River Site RF Atkinson*, Colorado State University, Fort Collins
Abstract: Any measurement result has associated uncertainties. This uncertainty analysis pertains to the tritium surface water sampling at five locations in the Savannah River. Uncertainties can result from the sampling routine, transport due to physical properties, equipment limitations and sample measurements. The only uncertainty reported presently is counting uncertainty. The main focus of this paper will be to give an overview of all uncertainties in the tritium measurements, estimate the total uncertainty, and propose experiments to verify some of the estimated uncertainties. The main uncertainties discovered and researched in this paper are tritium absorption or desorption in the sample container, fractionization during distillation, pipette volume, and tritium standard uncertainty. The goal is to quantify uncertainties to increase the scientific depth of the Savannah River Site Environmental Annual Report.
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Population Protection and Monitoring in Response to Radiological Incidents Eva Lee*, Georgia Institute of Technology
Abstract: Emergency response and medical preparedness for radiological incidents is one of the critical cornerstones for Homeland Security, along with biological and chemical incidents. The Three Mile Island and the Chernobyl nuclear accidents, and more urgently the recent event at the Fukushima Daiichi nuclear plants in Japan underscore the paramount importance of such emergency and medical preparedness and response capability. Such needs are wide-spread as many nations employ nuclear plants for energy generation.
In the first talk, we will discuss the development and deployment of a simulation and decision support system, RealOpt© along with the knowledge data bank that can be used by regional and local radiation and public health administrators to prepare for and deal with radiological emergency situations.
The system allows emergency planners to: i) Determine efficient resource allocation and operations for rapid screening and emergency response, accommodating on-the-fly changes as the situation evolves; ii) monitor within-center cross contamination propagation and provide guidance on dynamic triage responses to minimize it; iii) train regional radiation and public health agents for emergency preparedness and familiarize them with procedural steps for screening and decontamination, and emergency services; iv) analyze and assess the adequacy of existing resources (locally and/or regionally), and identify budget and labor needs to accommodate emergency responses; and/or maximize throughput under resource constraints during real situations; v) estimate costs and resources needed for the protection of the general population; and vi) perform large-scale virtual exercises. Such system is critical not only for population health monitoring, it is also important for rapid screening of workers during the emergency management of nuclear plant failure.
In the second talk, we will share our on-the-ground experience regarding the Japan Fukushima nuclear incidents. Especially, we will discuss the impact to the 900 Japanese families who lived within 20 kilometres from the failed nuclear plants. The discussion will be based on data collected regarding timelines for evacuation, screening, health status, radiological awareness and sociological information of the local population and workers, and subsequent psychological and medical impacts. We also highlight the use of RealOpt© in establishing a network of screening centers that facilitate efficient and rapid screening for patients and for health monitoring.
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Residual Radiation Exposure at Hiroshima and Nagasaki - A Historical Perspective G. D. Kerr*, Kerr Consulting, Knoxville, TN & Oak Ridge Associated Universities
Abstract: On 6 August 1945, the first atomic bomb was dropped on Hiroshima, and three days later, on 9 August, a second atomic bomb was dropped on Nagasaki. Immediately after the bombings, several teams of Japanese scientists visited Hiroshima and Nagasaki to investigate the extent of the damage and the residual radiation levels in the two cities. In early September 1945, the Science Research Council of Japan, now the Science Council of Japan, mobilized available scientists to study all aspects of the bombings, including residual radiation. Results of these investigations were published by the Science Council of Japan in a 1953 report entitled "Collection of Reports of the Investigations of the Atomic Bomb Casualties." The two bombs were exploded at sufficiently high altitudes to minimize fallout at both cities, and plans were made to monitor for fallout from the explosions in both Japan and the U.S. For example, the radioactive cloud from the Hiroshima explosion was monitored as it approached the west coast of the U.S. and followed inland as far as Lake Michigan. In addition, plans were developed to measure the residual radiation levels on the ground at Hiroshima from an airplane flying at an altitude of about 500 feet (150 meters); however, the flight over Hiroshima was not made because U.S. Army, Navy, and Manhattan Project teams were able to enter Japan in late September 1945. The work of the U.S. Navy team was published in a report by N. Pace and R. E. Smith entitled "Measurement of the Residual Radiation Intensity at the Hiroshima and Nagasaki Bombing Sites", and the work of the Manhattan Project team was published in a report by R. A. Tybout entitled "Radiation in Hiroshima and Nagasaki". The Tybout report was later published as U.S. Atomic Energy Commission report AEC WO-170 and the Pace and Smith report was later published as Atomic Bomb Casualty Commission report ABCC TR 26-59. The fallout areas were found to be primarily outside the major urban areas of the two cities. At Hiroshima, the major fallout area was in a region to the north and west of the city, and at Nagasaki, the major fallout area was in Nishiyama located several kilometers east of the city. The residual radiation in the major urban areas of the cities was determined to be primarily due to neutron activation products in the soil.
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Residual Radiation Exposure at Hiroshima and Nagasaki - A Historical Perspective G. D. Kerr*, Kerr Consulting, Knoxville, TN and Oak Ridge Associated Universities
Abstract: On 6 August, the first atomic bomb was dropped on Hiroshima, and three days later, on 9 August, a second atomic bomb was dropped on Nagasaki. Immediately after the bombings, several teams of Japanese scientists visited Hiroshima and Nagasaki to investigate the extent of the damage and residual radiation levels in the two cities. In early September 1954, teams of Japanese scientist were mobilized to investigate all aspects of the bombings. Results of these investigations were published by the Japanese Science Promotion Society in a 1953 report entitled "Collection of Investigative Reports on Atomic Bomb Disaster." The two bombs were exploded at sufficiently high altitudes to minimize fallout at both cities, and plans were made to monitor for fallout from the explosions in both Japan and the U.S. For example, the radioactive cloud from the Hiroshima explosion was monitored as it approached the west coast of the U.S. and followed inland as far as Lake Michigan. In addition, plans were developed to measure the residual radiation levels on the ground at Hiroshima from an airplane flying at an altitude of about 500 feet (150 meters); however, the flight over Hiroshima was not made because U.S. Army, Navy, and Manhattan Project teams were able to enter Japan in late September 1945. The work of the U.S. Navy team was published in a report by N. Pace and R. E. Smith entitled "Measurement of the Residual Radiation Intensity at the Hiroshima and Nagasaki Bombing Sites", and the work of the Manhattan Project team was published in a report by R. A. Tybout entitled "Radiation in Hiroshima and Nagasaki". The Tybout report was later published as U.S. Atomic Commission report AEC Wo-170 and the Pace and Smith report was later published as Atomic Bomb Casualty Commission report ABCC TR 26-59. The fallout areas were found to be primarily outside the major urban areas of the two cities. At Hiroshima, the major fallout area was in a region to the north and west of the city, and at Nagasaki, the major fallout area was in Nishiyama located several kilometers east of the city. The residual radiation in the major urban areas of the cities was determined to be due primarily to neutron activation of the soil.
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Accurate Determination of Beta Dose-Point-Kernels for High Z Sources in Non-Homogeneous Geometries C. D. Mangini*, Oregon State University, Department of Nuclear Engineering and Radiation Health Physics
; J. A. Caffrey, Oregon State University, Department of Nuclear Engineering and Radiation Health Physics; D. M. Hamby, Oregon State University, Department of Nuclear Engineering and Radiation Health Physics
Abstract: ‘Hot particle' skin dosimetry measurements are commonly performed using homogeneous dose-point-kernels (DPK) in conjunction with a scaling method to account for non-homogenous geometries. A model for determining the actual DPK for beta particles transmitted by a source of a different medium is presented. The model is based on an accurate determination of the amount of mono-energetic electron absorption that occurs in a given source thickness through the use of EGSnrc (Electron Gamma Shower) Monte Carlo simulations. Integration over a particular beta spectrum provides the beta particle DPK following self-absorption at each spectral energy, thereby accounting for spectrum hardening that may occur in higher Z materials. Beta spectra of varying spectral shapes and endpoint energies are used to test the new model for select source materials with 13≤Z≤95. The resulting DPK’s are then implemented into the computer code VARSKIN for dose testing with volumetric sources. It is shown that the proposed new DPK model for non-homogenous geometries is a significant improvement over current scaling methods and that resulting dose calculations agree very well with MCNP5 (Monte Carlo N-Particle Version 5) simulations. In addition, results are presented for a new scattering correction model that can better account for beta particle scattering both in the source medium and in the medium surrounding the source. The model relies on the selective integration of point source backscatter correction factors (BSCF) over a given source geometry. Selection criteria are based on individual source-point positions within the source and determine which, if any, BSCF’s are used. Dose testing results demonstrate increased accuracy over the volumetric scattering correction model currently implemented in VARSKIN. Overall, the results presented indicate that significant improvements can be made to DPK-based codes when dealing with high Z volume sources in non-homogeneous geometries.
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16:45 Health Effects Of Radiation to the Gamete, Embryo, Fetus, and Nursing Infant Robert L. Brent*, Thomas Jefferson University
; Jerrold T. Bushberg, University of California, Davis Health System; Donald P. Frush , Duke University Medical Center; Roger W. Harms, Mayo Clinic; Martha S. Linet, National Cancer Institute; John J. Mulvihill, University of Oklahoma; Robert O. Gorson, Columbia, South Carolina; Linda A. Kroger, University of California, Davis Health System; Andrew D. Maidment, University of Pennsylvania; Marvin C. Ziskin, Temple University
Abstract: In 1977, NCRP published Report No. 54 “Medical Radiation Exposure of Pregnant and Potentially Pregnant Women”. Since its publication there have been many advances in our knowledge of radiation induced risks prior to conception and during pregnancy as well as advances in reproductive biology and medical imaging. In 1977, body CT scanners were just being introduced into clinical practice; MRI only existed as prototypes; analog compound ultrasound imaging was still widely utilized and the first commercial PET systems were becoming part of the nuclear medicine imaging armamentarium. Since that time, the widespread use of these technologies in medical imaging (including the imaging of the pregnant patient) has been accompanied by advances in our understanding of radiation induced health risks. NCRP Scientific Committee 4-4 was charged with updating the previous report and expanding its scope to include preconception effects; recommendations to minimize the risk to the nursing infant following nuclear medicine studies and risks from non-ionizing sources of fetal exposure. The new report represents a comprehensive in-depth review of radiation risks and potential outcomes, including congenital malformations, growth retardation, miscarriage and stillbirth, mental retardation and neurobehavioral effects, and cancer risks in the offspring of mothers exposed to radiation during pregnancy. Potential reproductive and developmental effects of exposure to various sources of non-ionizing radiation, including medical ultrasound, radiofrequency fields and magnetic resonance imaging, are discussed. New data from the Radiation Effects Research Foundation studying survivors who were exposed in utero to radiation from the atomic bombs in Hiroshima and Nagasaki have provided important information regarding the scope and magnitude of radiation induced risk. Proper counseling of exposed individuals is also very important because misinformation is often provided to those concerned. The report includes many clinical cases studies that should be helpful to counselors-in-training. The draft report entitled, “Health Effects Of Radiation to the Gamete, Embryo, Fetus, and Nursing Infant”, was reviewed by the NCRP council in March and the final report is expected to be published in 2012.
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