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Dose refinement: ARAC's role

Description: The Atmospheric Release Advisory Capability (ARAC), located at the Lawrence Livermore National Laboratory, since the late 1970�s has been involved in assessing consequences from nuclear and other hazardous material releases into the atmosphere. ARAC�s primary role has been emergency response. However, after the emergency phase, there is still a significant role for dispersion modeling. This work usually involves refining the source term and, hence, the dose to the populations affected as additional information becomes available in the form of source term estimates�release rates, mix of material, and release geometry�and any measurements from passage of the plume and deposition on the ground. Many of the ARAC responses have been documented elsewhere. 1 Some of the more notable radiological releases that ARAC has participated in the post-emergency phase have been the 1979 Three Mile Island nuclear power plant (NPP) accident outside Harrisburg, PA, the 1986 Chernobyl NPP accident in the Ukraine, and the 1996 Japan Tokai nuclear processing plant explosion. ARAC has also done post-emergency phase analyses for the 1978 Russian satellite COSMOS 954 reentry and subsequent partial burn up of its on board nuclear reactor depositing radioactive materials on the ground in Canada, the 1986 uranium hexafluoride spill in Gore, OK, the 1993 Russian Tomsk-7 nuclear waste tank explosion, and lesser releases of mostly tritium. In addition, ARAC has performed a key role in the contingency planning for possible accidental releases during the launch of spacecraft with radioisotope thermoelectric generators (RTGs) on board (i.e. Galileo, Ulysses, Mars-Pathfinder, and Cassini), and routinely exercises with the Federal Radiological Monitoring and Assessment Center (FRMAC) in preparation for offsite consequences of radiological releases from NPPs and nuclear weapon accidents or incidents. Several accident post-emergency phase assessments are discussed in this paper in order to illustrate ARAC�s roll in dose refinement. A brief description of the ...
Date: June 1, 1998
Creator: Baskett, R L; Ellis, J S & Sullivan, T J
Partner: UNT Libraries Government Documents Department

Development of a Rapidly Deployed Department of Energy Emergency Response Element

Description: The Federal Radiological Emergency Response Plan (FRERP) directs the Department of Energy (DOE) to maintain a viable, timely, and fully documented response option capable of supporting the responsible Lead Federal Agency in the event of a radiological emergency impacting any state or US territory (e.g., CONUS). In addition, the DOE maintains a response option to support radiological emergencies outside the continental US (OCONUS). While the OCUNUS mission is not governed by the FREP, this response is operationally similar to that assigned to the DOE by the FREP. The DOE is prepared to alert, activate, and deploy radiological response teams to augment the Radiological Assistance Program and/or local responders. The Radiological Monitoring and Assessment Center (RMAC) is a phased response that integrates with the Federal Radiological Monitoring and Assessment Center (FRMAC) in CONUS environments and represents a stand-alone DOE response for OCONUS environments. The FRMAC/RMAC Phase I was formally ''stood up'' as an operational element in April 1999. The FRMAC/RMAC Phase II proposed ''stand-up'' date is midyear 2000.
Date: October 1, 1999
Creator: Riland, C.A.; Hopkins, R.C. & Tighe, R.J.
Partner: UNT Libraries Government Documents Department

Post-accident inhalation exposure and experience with plutonium

Description: This paper addresses the issue of inhalation exposure immediately afterward and for a long time following a nuclear accident. For the cases where either a nuclear weapon burns or explodes prior to nuclear fission, or at locations close to a nuclear reactor accident containing fission products, a major concern is the inhalation of aerosolized plutonium (Pu) particles producing alpha-radiation. We have conducted field studies of Pu- contaminated real and simulated accident sites at Bikini, Johnston Atoll, Tonopah (Nevada), Palomares (Spain), Chernobyl, and Maralinga (Australia).
Date: June 1, 1998
Creator: Shinn, J
Partner: UNT Libraries Government Documents Department

Accident consequence calculations for project W-058 safetyanalysis

Description: Accident consequence analyses have been performed for Project W-058, the Replacement Cross Site Transfer System. using the assumption and analysis techniques developed for the Tank Remediation Waste system Basis for Interim Operation. most potential accident involving the FISTS are bounded by the TWRS BIO analysis. However, the spray leak and pool leak scenarios require revised analyses since the RCSTS design utilizes larger diameter pipe and higher pressures than those analyzed in the TWRS BIO. Also the volume of diversion box and vent station are larger than that assumed for the valve pits in the TWRS BIO, which effects results of sprays or spills into the pits. the revised analysis for the spray leak is presented in Section 2, for the above ground spill in Section 3, for the presented in Section 2, for the above ground spill in Section 3, for the subsurface spill forming a pool in Section 4, and for the subsurface pool remaining subsurface in Section 5. The conclusion from these sections are summarized below.
Date: June 10, 1997
Creator: Van Keuren, J.C.
Partner: UNT Libraries Government Documents Department

Sandia Lightning Simulation Facility Building 888. Hazards assessment document

Description: The Department of Energy Order 5500.3A requires facility-specific hazards assessments be prepared, maintained, and used for emergency planning purposes. This hazards assessment document describes the chemical and radiological hazards associated with the Sandia Lightning Simulation Facility, Building 888. The entire inventory was screened according to the potential airborne impact to onsite and offsite individuals. The air dispersion model, ALOHA, estimated pollutant concentrations downwind from the source of a release, taking into consideration the toxicological and physical characteristics of the release site, the atmospheric conditions, and the circumstances of the release. The greatest distance at which a postulated facility event will produce consequences exceeding the Early Severe Health Effects threshold is 23 meters. The highest emergency classification is a Site Area Emergency. The Emergency Planning Zone is 65 meters.
Date: October 1, 1994
Creator: Banda, Z. & Barnett, B.
Partner: UNT Libraries Government Documents Department

Enforcement handbook: Enforcement of DOE nuclear safety requirements

Description: This Handbook provides detailed guidance and procedures to implement the General Statement of DOE Enforcement Policy (Enforcement Policy or Policy). A copy of this Enforcement Policy is included for ready reference in Appendix D. The guidance provided in this Handbook is qualified, however, by the admonishment to exercise discretion in determining the proper disposition of each potential enforcement action. As discussed in subsequent chapters, the Enforcement and Investigation Staff will apply a number of factors in assessing each potential enforcement situation. Enforcement sanctions are imposed in accordance with the Enforcement Policy for the purpose of promoting public and worker health and safety in the performance of activities at DOE facilities by DOE contractors (and their subcontractors and suppliers) who are indemnified under the Price-Anderson Amendments Act. These indemnified contractors, and their suppliers and subcontractors, will be referred to in this Handbook collectively as DOE contractors. It should be remembered that the purpose of the Department`s enforcement policy is to improve nuclear safety for the workers and the public, and this goal should be the prime consideration in exercising enforcement discretion.
Date: June 1, 1995
Partner: UNT Libraries Government Documents Department

Nuclear criticality safety: 2-day training course

Description: This compilation of notes is presented as a source reference for the criticality safety course. At the completion of this training course, the attendee will: be able to define terms commonly used in nuclear criticality safety; be able to appreciate the fundamentals of nuclear criticality safety; be able to identify factors which affect nuclear criticality safety; be able to identify examples of criticality controls as used as Los Alamos; be able to identify examples of circumstances present during criticality accidents; have participated in conducting two critical experiments; be asked to complete a critique of the nuclear criticality safety training course.
Date: February 1, 1997
Creator: Schlesser, J.A.
Partner: UNT Libraries Government Documents Department

Human radiation studies: Remembering the early years. Oral history of Julie Langham Grilly, February 3, 1995

Description: Julie Langham Grilly was interviewed by representatives of the US DOE Office of Human Radiation Experiments (OHRE) being the widow of Dr. Wright Langham, an investigator of principal interest of the committee. Her extensive experience with research at LANL was also of interest to the committee. Following a brief biographical sketch, Ms. Grilly relates her early postwar experience and her knowledge of Wright Langham`s involvement in animal research at Los Alamos, radiolanthanum tests on monkeys, Eniwetok tissue examinations, research on tritium uptake in humans, plutonium injections, tritium injections, EDTA, and etc. In addition to illuminating her former husband as a researcher and as an individual, she also relates her remembrances of Louis Hempelman, Enrico Fermi, Oppenheimer, Edward Teller, and many others.
Date: September 1, 1995
Partner: UNT Libraries Government Documents Department

The radiological assessment system for consequence analysis - RASCAL

Description: The Radiological Assessment System for Consequence Analysis, Version 2.1 (RASCAL 2.1) has been developed for use during a response to radiological emergencies. The model estimates doses for comparison with U.S. Environmental Protection Agency (EPA) Protective Action Guides (PAGs) and thresholds for acute health effects. RASCAL was designed to be used by U.S. Nuclear Regulatory Commission (NRC) personnel who report to the site of a nuclear accident to conduct an independent evaluation of dose and consequence projections and personnel who conduct training and drills on emergency responses. It allows consideration of the dominant aspects of the source term, transport, dose, and consequences. RASCAL consists of three computational tools: ST-DOSE, FM-DOSE, and DECAY. ST-DOSE computes source term, atmospheric transport, and dose to man from accidental airborne releases of radionuclides. The source-term calculations are appropriate for accidents at U.S. power reactors. FM-DOSE computes doses from environmental concentrations of radionuclides in the air and on the ground. DECAY computes radiological decay and daughter in-growth. RASCAL 2.1 is a DOS application that can be run under Windows 3.1 and 95. RASCAL has been the starting point for other accident consequence models, notably INTERRAS, an international version of RASCAL, and HASCAL, an expansion of RASCAL that will model radiological, biological, and chemical accidents.
Date: April 1, 1996
Creator: Sjoreen, A.L.; Ramsdell, J.V. & Athey, G.F.
Partner: UNT Libraries Government Documents Department

Recent MELCOR and VICTORIA Fission Product Research at the NRC

Description: The MELCOR and VICTORIA severe accident analysis codes, which were developed at Sandia National Laboratories for the U. S. Nuclear Regulatory Commission, are designed to estimate fission product releases during nuclear reactor accidents in light water reactors. MELCOR is an integrated plant-assessment code that models the key phenomena in adequate detail for risk-assessment purposes. VICTORIA is a more specialized fission- product code that provides detailed modeling of chemical reactions and aerosol processes under the high-temperature conditions encountered in the reactor coolant system during a severe reactor accident. This paper focuses on recent enhancements and assessments of the two codes in the area of fission product chemistry modeling. Recently, a model for iodine chemistry in aqueous pools in the containment building was incorporated into the MELCOR code. The model calculates dissolution of iodine into the pool and releases of organic and inorganic iodine vapors from the pool into the containment atmosphere. The main purpose of this model is to evaluate the effect of long-term revolatilization of dissolved iodine. Inputs to the model include dose rate in the pool, the amount of chloride-containing polymer, such as Hypalon, and the amount of buffering agents in the containment. Model predictions are compared against the Radioiodine Test Facility (RTF) experiments conduced by Atomic Energy of Canada Limited (AECL), specifically International Standard Problem 41. Improvements to VICTORIA's chemical reactions models were implemented as a result of recommendations from a peer review of VICTORIA that was completed last year. Specifically, an option is now included to model aerosols and deposited fission products as three condensed phases in addition to the original option of a single condensed phase. The three-condensed-phase model results in somewhat higher predicted fission product volatilities than does the single-condensed-phase model. Modeling of U02 thermochemistry was also improved, and results in better prediction of vaporization ...
Date: January 21, 1999
Creator: Bixler, N.E.; Cole, R.K.; Gauntt, R.O.; Schaperow, J.H. & Young, M.F.
Partner: UNT Libraries Government Documents Department

EPR dosimetry teeth in past and future accidents: A prospective look at a retrospective method

Description: Accurate assessments of doses received by individuals exposed to radiation from nuclear accidents and incidents such as those at Hiroshima and Nagasaki, the Nevada test site, Cheliabinsk and Mayak are required for epidemiological studies seeking to establish relationships between radiation dose and health effects. One method of retrospective dosimetry which allows for measurement of cumulative gamma ray doses received by exposed individuals is electron paramagnetic resonance spectroscopy (EPR) of tooth enamel. Tooth enamel stores and retains, indefinitely, information on absorbed radiation dose. And teeth are available in every population as a result of dental extraction for medical reasons including periodontal disease and impacted wisdom teeth. In the case of children, deciduous teeth, which are shed between the ages of 7 and 13, can be a very important dosimetric source if documented collection is implemented shortly following an accident.
Date: March 1, 1997
Creator: Haskell, E.; Kenner, G.; Hayes, R.; Chumak, V. & Shalom, S.
Partner: UNT Libraries Government Documents Department

Definition and means of maintaining the criticality detectors and alarms portion of the PFP safety envelope

Description: The Criticality Alarm System (CAS) provides continuous detection for high radiation (criticality) events and automatically initiates an evacuation signal to affected personnel. The Safety Envelope (SE) for PFP includes the necessary equipment and the required procedures to ensure the CAS is capable of performing its intended function. This document provides the definition and means of maintaining the SE for PFP related to the CAS. This document also identifies and provides a justification for those portions of the CAS excluded from the PFP Safety Envelope.
Date: August 25, 1997
Creator: White, W.F.
Partner: UNT Libraries Government Documents Department

Risk ranking methodology for radiological events

Description: Risk ranking schemes have been used in safety analysis to distinguish lower risk accidents from higher risk accidents. This is necessary to identify those events that might warrant additional study/quantitative analysis and to ensure that any resources allocated for risk reduction are properly directed. A common method used for risk ranking utilizes risk matrices. These are typically 3x3 or 4X4 matrices, having event consequences along one ixis and event frequency along the other. Each block on the risk mitrix represents some level of risk, and blocks presenting similar risk are often grouped together into one of 3 or 4 risk regions. Once a risk matrix has been identified, events are placed on the matrix based on an estimate of the event consequence and event frequency. Knowing how the blocks on the risk matrix relate to one another with respect to risk, the relative risk of the events will be known based on where they are placed on the matrix. In most cases, the frequency axis of the matrix has some numerical values associated with it, and this typically spans several orders of magnitude. Often, the consequence axis is based on a qualitative scale, where consequences are judgment based. However, the consequence scale generally has implicit qualitative values associated with it, which may or may not be recognized. Risk regions are often arbitrarily assigned (or assigned on the basis of symmetry). This presents a problem in that if the blocks of the risk matrix are incorrectly grouped, then incorrect conclusions can be drawn about the relative risk presented by events at a facility. This paper first describes how risk matrices have typically been established in the past. Problems associated with these risk matrices are identified and discussed. A methodology for logically establishing risk matrices, with specific application to radiological risk is ...
Date: March 1, 1997
Creator: Altenbach, T., Brezeton, S.
Partner: UNT Libraries Government Documents Department

Estimates of fission yields in nuclear criticality excursions

Description: There is a need for computer simulation of hypothetical criticality excursions involving significant quantities of fissionable materials, especially in fissile aqueous system. The need arises due to the requirements for the emergency planning of facilities where the fissionable materials are handled, processed, or stored; and the regulatory requirements associated with facility operation or conversion. It is proposed here that a data base of fission yeilds for critical experiments and known accidents (both aqueous and solid) should be generated by using existing or new computer codes. The success in compiling this data base would provide useful source-terms for criticality excursions, realistic estimates of emergency-response boundary, as well as a replacement for the ``rule-of-thumb`` or ``bounding`` method. 10 refs.
Date: June 1, 1995
Creator: Choi, J.S.; Thompson, J.W. & Reed, R.
Partner: UNT Libraries Government Documents Department

Federal Radiological Monitoring and Assessment Center advanced part phase response actions

Description: Federal Radiological Monitoring and Assessment Center (FRMAC) response actions are carried out in Advance Party and Main Party phases of deployment. Response activities are initiated by a FRMAC Home Team prior to and during Advance Party deployment, with Home Team support continuing until the FRMAC Main Party is fully deployed. Upon arrival at the incident scene, the Advance Party establishes communications with other federal, state, and local response organizations, Following an Advance Party Meeting with these response organizations, FRMAC begins formulation of an initial monitoring and sampling plan, in coordination with the jurisdictional state and the Lead Federal Agency, and initiates detailed logistical arrangements for Main Party deployment and operations.
Date: February 1, 1997
Creator: Hurley, B.
Partner: UNT Libraries Government Documents Department

Slide Rule for Rapid Response Estimation of Radiological Dose from Criticality Accidents

Description: This paper describes a functional slide rule that provides a readily usable �in-hand� method for estimating nuclear criticality accident information from sliding graphs, thereby permitting (1) the rapid estimation of pertinent criticality accident information without laborious or sophisticated calculations in a nuclear criticality emergency situation, (2) the appraisal of potential fission yields and external personnel radiation exposures for facility safety analyses, and (3) a technical basis for emergency preparedness and training programs at nonreactor nuclear facilities. The slide rule permits the estimation of neutron and gamma dose rates and integrated doses based upon estimated fission yields, distance from the fission source, and time-after criticality accidents for five different critical systems. Another sliding graph permits the estimation of critical solution fission yields based upon fissile material concentration, critical vessel geometry, and solution addition rate. Another graph provides neutron and gamma dose-reduction factors for water, steel, and concrete shields.
Date: September 20, 1999
Creator: Broadhead, B. L.; Childs, R. L.; Hopper, C. M. & Parks, C. V.
Partner: UNT Libraries Government Documents Department

Modeling atmospheric deposition using a stochastic transport model

Description: An advanced stochastic transport model has been modified to include the removal mechanisms of dry and wet deposition. Time-dependent wind and turbulence fields are generated with a prognostic mesoscale numerical model and are used to advect and disperse individually released particles that are each assigned a mass. These particles are subjected to mass reduction in two ways depending on their physical location. Particles near the surface experience a decrease in mass using the concept of a dry deposition velocity, while the mass of particles located within areas of precipitation are depleted using a scavenging coefficient. Two levels of complexity are incorporated into the particle model. The simple case assumes constant values of dry deposition velocity and scavenging coefficient, while the more complex case varies the values according to meteorology, surface conditions, release material, and precipitation intensity. Instantaneous and cumulative dry and wet deposition are determined from the mass loss due to these physical mechanisms. A useful means of validating the model results is with data available from a recent accidental release of Cesium-137 from a steel-processing furnace in Algeciras, Spain in May, 1998. This paper describes the deposition modeling technique, as well as a comparison of simulated concentration and deposition with measurements taken for the Algeciras release.
Date: December 17, 1999
Creator: Buckley, R. L.
Partner: UNT Libraries Government Documents Department

Systematics of Reconstructed Process Facility Criticality Accidents

Description: The systematics of the characteristics of twenty-one criticality accidents occurring in nuclear processing facilities of the Russian Federation, the United States, and the United Kingdom are examined. By systematics the authors mean the degree of consistency or agreement between the factual parameters reported for the accidents and the experimentally known conditions for criticality. The twenty-one reported process criticality accidents are not sufficiently well described to justify attempting detailed neutronic modeling. However, results of classic hand calculations confirm the credibility of the reported accident conditions.
Date: September 19, 1999
Creator: Pruvost, N.L.; McLaughlin, T.P. & Monahan, S.P.
Partner: UNT Libraries Government Documents Department

Radiological Emergency Response Health and Safety Manual

Description: This manual was created to provide health and safety (H&S) guidance for emergency response operations. The manual is organized in sections that define each aspect of H and S Management for emergency responses. The sections are as follows: Responsibilities; Health Physics; Industrial Hygiene; Safety; Environmental Compliance; Medical; and Record Maintenance. Each section gives guidance on the types of training expected for managers and responders, safety processes and procedures to be followed when performing work, and what is expected of managers and participants. Also included are generic forms that will be used to facilitate or document activities during an emergency response. These ensure consistency in creating useful real-time and archival records and help to prevent the loss or omission of information.
Date: May 2001
Creator: Bowman, D. R.
Partner: UNT Libraries Government Documents Department