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FRMAC Assessment Manual

Description: The ingestion pathway assessment procedures cited in the current version of the ``RMAC Assessment Manual'', DOE/NV/11718-061 (September 1996) have been superseded by new US Food and Drug Administration (FDA) guidance. This addendum replaces the obsolete procedures with a revised set based on the new guidance released by the FDA in August 1998. This addendum provides an overview of the new guidance, revised assessment methods, and assessment aids. It does not provide a general method of ingestion pathway analysis. The scope is limited to that covered by the new guidance titled, ``Accidental Radioactive Contamination of Human Food and Animal Feeds: Recommendations for State and Local Agencies,'' issued by the FDA in August 1998.
Date: December 1, 1999
Creator: Clark, H.
Partner: UNT Libraries Government Documents Department

Corrective Action Decision Document for Corrective Action Unit 417: Central Nevada Test Area Surface, Nevada

Description: This Corrective Action Decision Document (CADD) identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's selection of a recommended corrective action alternative (CAA) appropriate to facilitate the closure of Corrective Action Unit (CAU) 417: Central Nevada Test Area Surface, Nevada, under the Federal Facility Agreement and Consent Order. Located in Hot Creek Valley in Nye County, Nevada, and consisting of three separate land withdrawal areas (UC-1, UC-3, and UC-4), CAU 417 is comprised of 34 corrective action sites (CASs) including 2 underground storage tanks, 5 septic systems, 8 shaker pad/cuttings disposal areas, 1 decontamination facility pit, 1 burn area, 1 scrap/trash dump, 1 outlier area, 8 housekeeping sites, and 16 mud pits. Four field events were conducted between September 1996 and June 1998 to complete a corrective action investigation indicating that the only contaminant of concern was total petroleum hydrocarbon (TPH) which was found in 18 of the CASs. A total of 1,028 samples were analyzed. During this investigation, a statistical approach was used to determine which depth intervals or layers inside individual mud pits and shaker pad areas were above the State action levels for the TPH. Other related field sampling activities (i.e., expedited site characterization methods, surface geophysical surveys, direct-push geophysical surveys, direct-push soil sampling, and rotosonic drilling located septic leachfields) were conducted in this four-phase investigation; however, no further contaminants of concern (COCs) were identified. During and after the investigation activities, several of the sites which had surface debris but no COCs were cleaned up as housekeeping sites, two septic tanks were closed in place, and two underground storage tanks were removed. The focus of this CADD was to identify CAAs which would promote the prevention or mitigation of human exposure to surface and subsurface soils with contaminant concentrations above preliminary action levels. Based on ...
Date: April 2, 1999
Creator: United States. Department of Energy. Nevada Operations Office.
Partner: UNT Libraries Government Documents Department

Corrective Action Decision Document for Corrective Action Unit 417: Central Nevada Test Area Surface, Nevada Appendix D - Corrective Action Investigation Report, Central Nevada Test Area, CAU 417

Description: This Corrective Action Decision Document (CADD) identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's selection of a recommended corrective action alternative (CAA) appropriate to facilitate the closure of Corrective Action Unit (CAU) 417: Central Nevada Test Area Surface, Nevada, under the Federal Facility Agreement and Consent Order. Located in Hot Creek Valley in Nye County, Nevada, and consisting of three separate land withdrawal areas (UC-1, UC-3, and UC-4), CAU 417 is comprised of 34 corrective action sites (CASs) including 2 underground storage tanks, 5 septic systems, 8 shaker pad/cuttings disposal areas, 1 decontamination facility pit, 1 burn area, 1 scrap/trash dump, 1 outlier area, 8 housekeeping sites, and 16 mud pits. Four field events were conducted between September 1996 and June 1998 to complete a corrective action investigation indicating that the only contaminant of concern was total petroleum hydrocarbon (TPH) which was found in 18 of the CASs. A total of 1,028 samples were analyzed. During this investigation, a statistical approach was used to determine which depth intervals or layers inside individual mud pits and shaker pad areas were above the State action levels for the TPH. Other related field sampling activities (i.e., expedited site characterization methods, surface geophysical surveys, direct-push geophysical surveys, direct-push soil sampling, and rotosonic drilling located septic leachfields) were conducted in this four-phase investigation; however, no further contaminants of concern (COCs) were identified. During and after the investigation activities, several of the sites which had surface debris but no COCs were cleaned up as housekeeping sites, two septic tanks were closed in place, and two underground storage tanks were removed. The focus of this CADD was to identify CAAs which would promote the prevention or mitigation of human exposure to surface and subsurface soils with contaminant concentrations above preliminary action levels. Based on ...
Date: April 2, 1999
Creator: United States. Department of Energy.
Partner: UNT Libraries Government Documents Department

Proceedings of the workshop on review of dose modeling methods for demonstration of compliance with the radiological criteria for license termination

Description: The workshop was one in a series to support NRC staff development of guidance for implementing the final rule on ``Radiological Criteria for License Termination.`` The workshop topics included discussion of: dose models used for decommissioning reviews; identification of criteria for evaluating the acceptability of dose models; and selection of parameter values for demonstrating compliance with the final rule. The 2-day public workshop was jointly organized by RES and NMSS staff responsible for reviewing dose modeling methods used in decommissioning reviews. The workshop was noticed in the Federal Register (62 FR 51706). The workshop presenters included: NMSS and RES staff, who discussed both dose modeling needs for licensing reviews, and development of guidance related to dose modeling and parameter selection needs; DOE national laboratory scientists, who provided responses to earlier NRC staff-developed questions and discussed their various Federally-sponsored dose models (i.e., DandD, RESRAD, and MEPAS codes); and an EPA scientist, who presented details on the EPA dose assessment model (i.e., PRESTO code). The workshop was formatted to provide opportunities for the attendees to observe computer demonstrations of the dose codes presented. More than 120 workshop attendees from NRC Headquarters and the Regions, Agreement States; as well as industry representatives and consultants; scientists from EPA, DOD, DNFSB, DOE, and the national laboratories; and interested members of the public participated. A complete transcript of the workshop, including viewgraphs and attendance lists, is available in the NRC Public Document Room. This NUREG/CP documents the formal presentations made during the workshop, and provides a preface outlining the workshop`s focus, objectives, background, topics and questions provided to the invited speakers, and those raised during the panel discussion. NUREG/CP-0163 also provides technical bases supporting the development of decommissioning guidance. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.
Date: May 1, 1998
Creator: Nicholson, T. J. & Parrott, J. D.
Partner: UNT Libraries Government Documents Department

Soil contamination standards for protection of personnel

Description: The objective of this report is to recommend soil contamination levels that will ensure that radionuclide intakes by unprotected workers are likely to give internal doses below selected dose limits during the working year. The three internal dose limits are 1, 100, and 500 mrem per year. In addition, photon, beta, and alpha instrument readings are estimated for these soil concentration limits. Two exposure pathways are considered: the first is inhalation of resuspended dust and the second is ingestion of trace amounts of soil. In addition, radioactive decay and ingrowth of progeny during the year of exposure is included. External dose from the soil contamination is not included because monitoring and control of external exposures is carried out independently from internal exposures, which are the focus of this report. The methods used are similar to those used by Carbaugh and Bihl (1993) to set bioassay criteria for such workers.
Date: April 16, 1998
Creator: Rittmann, P.D.
Partner: UNT Libraries Government Documents Department

Isotopic signatures by bulk analyses

Description: Los Alamos National Laboratory has developed a series of measurement techniques for identification of nuclear signatures by analyzing bulk samples. Two specific applications for isotopic fingerprinting to identify the origin of anthropogenic radioactivity in bulk samples are presented. The first example is the analyses of environmental samples collected in the US Arctic to determine the impact of dumping of radionuclides in this polar region. Analyses of sediment and biota samples indicate that for the areas sampled the anthropogenic radionuclide content of sediments was predominantly the result of the deposition of global fallout. The anthropogenic radionuclide concentrations in fish, birds and mammals were very low. It can be surmised that marine food chains are presently not significantly affected. The second example is isotopic fingerprinting of water and sediment samples from the Rocky Flats Facility (RFP). The largest source of anthropogenic radioactivity presently affecting surface-waters at RFP is the sediments that are currently residing in the holding ponds. One gram of sediment from a holding pond contains approximately 50 times more plutonium than 1 liter of water from the pond. Essentially 100% of the uranium in Ponds A-1 and A-2 originated as depleted uranium. The largest source of radioactivity in the terminal Ponds A-4, B-5 and C-2 was naturally occurring uranium and its decay product radium. The uranium concentrations in the waters collected from the terminal ponds contained 0.05% or less of the interim standard calculated derived concentration guide for uranium in waters available to the public. All of the radioactivity observed in soil, sediment and water samples collected at RFP was naturally occurring, the result of processes at RFP or the result of global fallout. No extraneous anthropogenic alpha, beta or gamma activities were detected. The plutonium concentrations in Pond C-2 appear to vary seasonally.
Date: December 1, 1997
Creator: Efurd, D.W. & Rokop, D.J.
Partner: UNT Libraries Government Documents Department

Development of a building sump database for the Y-12 Plant, Oak Ridge, Tennessee

Description: Operations at the Oak Ridge Y-12 Plant have resulted in contamination of Upper East Fork Poplar Creek (UEFPC) and shallow groundwater through soil erosion, infiltration, and outfall discharges. The contamination of groundwater has been documented for nearly two decades, largely through well monitoring efforts. This study represents the first effort to formally identify and compile location data on sumps at the Y-12 Plant, several of which are known or are suspected to pump groundwater. Operation of several of these sumps have been documented to affect groundwater hydraulics and contaminant pathways. This report presents preliminary results of an investigation attempting to identify sources of data on building sumps that have not previously been incorporated into existing Y-12 Plant groundwater databases. This investigation involved acquiring information on building sumps, such as location, building number, water source, discharge location, and availability of analytical data. This information was used to construct an ARC/INFO database capable of simultaneously storing spatial data on sump locations and attribute information concerning the operation of individual building sumps. This database will be referred to hereafter as the Y-12 Plant Building Sump Database.
Date: July 1, 1997
Creator: Sepanski, R.J. & Field, S.M.
Partner: UNT Libraries Government Documents Department

Methodology for calculating guideline concentrations for safety shot sites

Description: Residual plutonium (Pu), with trace quantities of depleted uranium (DU) or weapons grade uranium (WU), exists in surficial soils at the Nevada Test Site (NTS), Nellis Air Force Range (NAFR), and the Tonopah Test Range (TTR) as the result of the above-ground testing of nuclear weapons and special experiments involving the detonation of plutonium-bearing devices. The special experiments (referred to as safety shots) involving plutonium-bearing devices were conducted to study the behavior of Pu as it was being explosively compressed; ensure that the accidental detonation of the chemical explosive in a production weapon would not result in criticality; evaluate the ability of personnel to manage large-scale Pu dispersal accidents; and develop criteria for transportation and storage of nuclear weapons. These sites do not pose a health threat to either workers or the general public because they are under active institutional control. The DOE is committed to remediating the safety shot sites so that radiation exposure to the public, both now and in the future, will be maintained within the established limits and be as low as reasonably achievable. Remediation requires calculation of a guideline concentration for the Pu, U, and their decay products that are present in the surface soil. This document presents the methodology for calculating guideline concentrations of weapons grade plutonium, weapons grade uranium, and depleted uranium in surface soils at the safety shot sites. Emphasis is placed on obtaining site-specific data for use in calculating dose to potential residents from the residual soil contamination.
Date: June 1, 1997
Partner: UNT Libraries Government Documents Department

A spatially-dynamic preliminary risk assessment of the American peregrine falcon at the Los Alamos National Laboratory (version 1)

Description: The Endangered Species Act and the Record of Decision on the Dual Axis Radiographic Hydrodynamic Test Facility at the Los Alamos National Laboratory require protection of the American peregrine falcon. A preliminary risk assessment of the peregrine was performed using a custom FORTRAN model and a geographical information system. Estimated doses to the falcon were compared against toxicity reference values to generate hazard indices. Hazard index results indicated no unacceptable risk to the falcon from the soil ingestion pathway, including a measure of cumulative effects from multiple contaminants that assumes a linear additive toxicity type. Scaling home ranges on the basis of maximizing falcon height for viewing prey decreased estimated risk by 69% in a canyons-based home range and increased estimated risk by 40% in a river-based home range. Improving model realism by weighting simulated falcon foraging based on distance from potential nest sites decreased risk by 93% in one exposure unit and by 82% in a second exposure unit. It was demonstrated that choice of toxicity reference values can have a substantial impact on risk estimates. Adding bioaccumulation factors for several organics increased partial hazard quotients by a factor of 110, but increased the mean hazard index by only 0.02 units. Adding a food consumption exposure pathway in the form of biomagnification factors for 15 contaminants of potential ecological concern increased the mean hazard index to 1.16 ({+-} 1.0), which is above the level of acceptability (1.0). Aroclor-1254, dichlorodiphenyltrichlorethane (DDT) and dichlorodiphenylethelyne (DDE) accounted for 81% of the estimated risk that includes soil ingestion and food consumption Contaminant pathways and a biomagnification component. Information on risk by specific geographical location was generated, which can be used to manage contaminated areas, falcon habitat, facility siting, and/or facility operations. 123 refs., 10 figs., 2 tabs.
Date: June 1, 1997
Creator: Gallegos, A.F.; Gonzales, G.J. & Bennett, K.D.
Partner: UNT Libraries Government Documents Department

Remedial investigation report on the Melton Valley Watershed at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 1: Evaluation, interpretation, and data summary

Description: The Melton Valley watershed presents a multifaceted management and decision-making challenge because of the very heterogeneous conditions that exist with respect to contaminant type, disposal unit age, mode of disposal, release mechanism, and potential risk-producing pathways. The investigation presented here has assembled relevant site data in the geographic context with the intent of enabling program managers and decision-makers to understand site conditions and evaluate the necessity, relative priority, and scope of potential remedial actions.
Date: May 1, 1997
Partner: UNT Libraries Government Documents Department

Remedial investigation report on the Melton Valley watershed at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 2: Appendixes A and B

Description: The Melton Valley watershed presents a multifaceted management and decision-making challenge because of the very heterogeneous conditions that exist with respect to contaminant type, disposal unit age, mode of disposal, release mechanism, and potential risk-producing pathways. The investigation presented here has assembled relevant site data in the geographic context with the intent of enabling program managers and decision-makers to understand site conditions and evaluate the necessity, relative priority, and scope of potential remedial actions. The industrial and recreational exposure scenarios are used to provide a risk assessment reference context to evaluate levels of contamination in surface water, groundwater, soil, and sediment within each subbasin of the Melton Valley watershed. All available analytical results for the media of interest that could be qualified for use in the risk assessment were screened to determine carcinogenic risk values and noncarcinogenic hazard indexes and to identify the chemicals of concern (COCs) for each evaluated media in each subbasin.
Date: May 1, 1997
Partner: UNT Libraries Government Documents Department

Remedial investigation report on the Melton Valley watershed at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 3: Appendix C

Description: The Melton Valley watershed presents a multifaceted management and decision-making challenge because of the very heterogeneous conditions that exist with respect to contaminant type, disposal unit age, mode of disposal, release mechanism, and potential risk-producing pathways. The investigation presented here has assembled relevant site data in the geographic context with the intent of enabling program managers and decision-makers to understand site conditions and evaluate the necessity, relative priority, and scope of potential remedial actions. The industrial and recreational exposure scenarios are used to provide a risk assessment reference context to evaluate levels of contamination in surface water, groundwater, soil, and sediment within each subbasin of the Melton Valley watershed. All available analytical results for the media of interest that could be qualified for use in the risk assessment were screened to determine carcinogenic risk values and noncarcinogenic hazard indexes and to identify the chemicals of concern (COCs) for each evaluated media in each subbasin.
Date: May 1, 1997
Partner: UNT Libraries Government Documents Department

A consolidated environmental monitoring plan for Aberdeen Proving Ground, Maryland

Description: The US Army operates facilities in Edgewood and Aberdeen under several licenses from the Nuclear Regulatory Commission (NRC). Compliance with each license is time consuming and could potentially result in duplicated efforts to demonstrate compliance with existing environmental regulations. The goal of the ERM plan is to provide the sampling necessary to ensure that operations at Edgewood and Aberdeen are within applicable regulatory guidelines and to provide a means of ensuring that adverse effects to the environment are minimized. Existing sampling plans and environmental data generated from those plans are briefly reviewed as part of the development of the present ERM plan. The new ERM plan was designed to provide data that can be used for assessing risks to the environment and to humans using Aberdeen and Edgewood areas. Existing sampling is modified and new sampling is proposed based on the results of the long-term DU fate study. In that study, different environmental pathways were identified that would show transport of DU at Aberdeen. Those pathways would also be impacted by other radioactive constituents from Aberdeen and Edgewood areas. The ERM plan presented in this document includes sampling from Edgewood and Aberdeen facilities. The main radioactive constituents of concern at Edgewood are C, P, N, S, H, I, Co, Cs, Ca, Sr and U that are used in radiolabeling different compounds and tracers for different reactions and syntheses. Air and water sampling are the thrust of efforts at the Edgewood area.
Date: April 1, 1997
Creator: Ebinger, M.H. & Hansen, W.R.
Partner: UNT Libraries Government Documents Department

Field characterization report on Phase 1 of the Bear Creek Valley treatability study, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

Description: A treatability study is being performed to investigate the practicability of using passive, in situ treatment systems to remove contaminants from the Bear Creek Valley (BCV) Characterization Area (CA). This draft document is a report of the site characterization results and is part of Phase 1 of this study. Field activities performed are outlined in Bear Creek Valley Passive Surface Water Treatment Technology Demonstrations, Phase 1, Site Characterization. The focus of the characterization was to obtain sufficient site-specific data on hydrogeology of NT-1, NT-2, and upper Bear Creek (above its confluence with NT-1) to support selection of groundwater capture and treatment systems in Phases 2 and 3. Groundwater samples from the S-3 Site and NT-1 area were also collected for the principal investigators to test during Phase 1 laboratory work. Three contaminant migration pathways were delineated in the S-3 Area. Each is described and briefly characterized by field observations and analysis of surface and groundwater collected within each pathway.
Date: April 1, 1997
Partner: UNT Libraries Government Documents Department

Application for approval of derived authorized limits for the release of the 190-C trenches and 105-C process water tunnels at the Hanford Site: Volume 2 - source term development

Description: As part of environmental restoration activities at the Hanford Site, Bechtel Hanford, Inc. is conducting a series of evaluations to determine appropriate release conditions for specific facilities following the completion of decontamination and decommissioning projects. The release conditions, with respect to the residual volumetric radioactive contamination, are termed authorized limits. This report presents the summary of the supporting information and the final application for approval of derived authorized limits for the release of the 190-C trenches and the 105-C process water tunnels. This document contains two volumes; this volume (Vol. 2) contains the radiological characterization data, spreadsheet analyses, and radiological source terms.
Date: March 1, 1997
Creator: Denham, D.H.; Winslow, S.L.; Moeller, M.P. & Kennedy, W.E. Jr.
Partner: UNT Libraries Government Documents Department

Application of the RESRAD computer code to VAMP scenario S

Description: The RESRAD computer code developed at Argonne National Laboratory was among 11 models from 11 countries participating in the international Scenario S validation of radiological assessment models with Chernobyl fallout data from southern Finland. The validation test was conducted by the Multiple Pathways Assessment Working Group of the Validation of Environmental Model Predictions (VAMP) program coordinated by the International Atomic Energy Agency. RESRAD was enhanced to provide an output of contaminant concentrations in environmental media and in food products to compare with measured data from southern Finland. Probability distributions for inputs that were judged to be most uncertain were obtained from the literature and from information provided in the scenario description prepared by the Finnish Centre for Radiation and Nuclear Safety. The deterministic version of RESRAD was run repeatedly to generate probability distributions for the required predictions. These predictions were used later to verify the probabilistic RESRAD code. The RESRAD predictions of radionuclide concentrations are compared with measured concentrations in selected food products. The radiological doses predicted by RESRAD are also compared with those estimated by the Finnish Centre for Radiation and Nuclear Safety.
Date: March 1, 1997
Creator: Gnanapragasam, E. K. & Yu, C.
Partner: UNT Libraries Government Documents Department

Code manual for MACCS2: Volume 1, user`s guide

Description: This report describes the use of the MACCS2 code. The document is primarily a user`s guide, though some model description information is included. MACCS2 represents a major enhancement of its predecessor MACCS, the MELCOR Accident Consequence Code System. MACCS, distributed by government code centers since 1990, was developed to evaluate the impacts of severe accidents at nuclear power plants on the surrounding public. The principal phenomena considered are atmospheric transport and deposition under time-variant meteorology, short- and long-term mitigative actions and exposure pathways, deterministic and stochastic health effects, and economic costs. No other U.S. code that is publicly available at present offers all these capabilities. MACCS2 was developed as a general-purpose tool applicable to diverse reactor and nonreactor facilities licensed by the Nuclear Regulatory Commission or operated by the Department of Energy or the Department of Defense. The MACCS2 package includes three primary enhancements: (1) a more flexible emergency-response model, (2) an expanded library of radionuclides, and (3) a semidynamic food-chain model. Other improvements are in the areas of phenomenological modeling and new output options. Initial installation of the code, written in FORTRAN 77, requires a 486 or higher IBM-compatible PC with 8 MB of RAM.
Date: March 1, 1997
Creator: Chanin, D.I. & Young, M.L.
Partner: UNT Libraries Government Documents Department

MACCS2 development and verification efforts

Description: MACCS2 represents a major enhancement of the capabilities of its predecessor MACCS, the MELCOR Accident Consequence Code System. MACCS, released in 1987, was developed to estimate the potential impacts to the surrounding public of severe accidents at nuclear power plants. The principal phenomena considered in MACCS/MACCS2 are atmospheric transport and deposition under time-variant meteorology, short-term and long-term mitigative actions and exposure pathways, deterministic and stochastic health effects, and economic costs. MACCS2 was developed as a general-purpose analytical tool applicable to diverse reactor and nonreactor facilities. The MACCS2 package includes three primary enhancements: (1) a more flexible emergency response model, (2) an expanded library of radionuclides, and (3) a semidynamic food-chain model. In addition, errors that had been identified in MACCS version1.5.11.1 were corrected, including an error that prevented the code from providing intermediate-phase results. MACCS2 version 1.10 beta test was released to the beta-test group in May, 1995. In addition, the University of New Mexico (UNM) has completed an independent verification study of the code package. Since the beta-test release of MACCS2 version 1.10, a number of minor errors have been identified and corrected, and a number of enhancements have been added to the code package. The code enhancements added since the beta-test release of version 1.10 include: (1) an option to allow the user to input the {sigma}{sub y} and {sigma}{sub z} plume expansion parameters in a table-lookup form for incremental downwind distances, (2) an option to define different initial dimensions for up to four segments of a release, (3) an enhancement to the COMIDA2 food-chain model preprocessor to allow the user to supply externally calculated tables of tritium food-chain dose per unit deposition on farmland to support analyses of tritium releases, and (4) the capability to calculate direction-dependent doses.
Date: March 1, 1997
Creator: Young, M. & Chanin, D.
Partner: UNT Libraries Government Documents Department

Dose calculations for the concrete water tunnels at 190-C Area, Hanford Site

Description: The RESRAD-BUILD code was used to calculate the radiological dose from the contaminated concrete water tunnels at the 190-C Area at the Hanford Site. Two exposure scenarios, recreationist and maintenance worker, were considered. A residential scenario was not considered because the material was assumed to be left intact (i.e., the concrete would not be rubbleized because the location would not be suitable for construction of a house). The recreationist was assumed to use the tunnel for 8 hours per day for 1 week as an overnight shelter. The maintenance worker was assumed to spend 20 hours per year working in the tunnel. Six exposure pathways were considered in calculating the dose. Three external exposure pathways involved penetrating radiation emitted directly from the contaminated tunnel floor, emitted from radioactive particulates deposited on the tunnel floor, and resulting from submersion in airborne radioactive particulates. Three internal exposure pathways involved inhalation of airborne radioactive particulates; inadvertent direct ingestion of removable, contaminated material on the tunnel floor; and inadvertent indirect ingestion of airborne particulates deposited on the tunnel floor. The gradual removal of surface contamination over time and the ingrowth of decay products were considered in calculating the dose at different times. The maximum doses were estimated to be 1.5 mrem/yr for the recreationist and 0.34 mrem/yr for the maintenance worker.
Date: January 1, 1997
Creator: Kamboj, S. & Yu, C.
Partner: UNT Libraries Government Documents Department

Radiological dose assessment for the decontaminated concrete removed from 183-H solar evaporation basins at the Hanford site, Richland, Washington

Description: Potential maximum radiation dose rates over a 1,000-year time horizon were calculated for exposure to the decontaminated concrete removed from the 183-H Solar Evaporation Basins at the Hanford Site, Richland, Washington. The RESRAD computer code, Version 5.62, which implements the methodology described in the US Department of Energy`s manual for developing residual radioactive material guidelines, was used in this evaluation. Currently, the concrete is not being used. Four potential exposure scenarios were developed for the land area where the decontaminated concrete will be stored. In Scenario A industrial use of the land is assumed; in Scenario B recreational use of the land is assumed; in Scenario C residential use of the land is assumed; and in Scenario D (a plausible but unlikely land-use scenario), the presence of a subsistence farmer in the immediate vicinity of the land is assumed. For Scenarios A and B, water used for drinking is assumed to be surface water from the Columbia River; for Scenarios C and D, groundwater drawn from a well located at the downgradient edge of the storage area is the only source of water for drinking, irrigation, and raising livestock. Conservative parameters values were used to estimate the radiation doses. The results of the evaluation indicate that the US Department of Energy`s dose limit of 100 mrem/yr would not be exceeded for any of the scenarios analyzed. The potential maximum dose rates for Scenarios A, B, C, and D are 0.75, 0.022, 29, 29 mrem/yr, respectively. An uncertainty analysis was performed to determine which parameters have the greatest impact on the estimated doses. The doses in Scenarios C and D were found to be very sensitive to the magnitude of the irrigation rate.
Date: January 1, 1997
Creator: Kamboj, S.; Faillace, E. & Yu, C.
Partner: UNT Libraries Government Documents Department

Comparison of radiological dose pathways for tank farm accidents

Description: This calculation note documents an evaluation of the doses from submersion and ground shine due to a release of tank farm radioactive materials, and a comparison of these doses to the doses from inhalation of the materials. The submersion and ground shine doses are insignificant compared to the inhalation doses. The doses from resuspension are also shown to be negligible for the tank farm analysis conditions.
Date: October 30, 1996
Creator: Van Keuren, J.C.
Partner: UNT Libraries Government Documents Department

7Q10 flows for SRS streams

Description: The Environmental Transport Group of the Environmental Technology Section was requested to predict the seven-day ten-year low flow (7Q10 flow) for the SRS streams based on historical stream flow records. Most of the historical flow records for the SRS streams include reactor coolant water discharged from the reactors and process water released from the process facilities. The most straight forward way to estimate the stream daily natural flow is to subtract the measured upstream reactor and/or facility daily effluents from the measured downstream daily flow. Unfortunately, this method does not always work, as indicated by the fact that sometimes the measured downstream volumetric flow rates are lower than the reactor effluent volumetric flow rates. For those cases that cannot be analyzed with the simple subtracting method, an alternative method was used to estimate the stream natural flows by statistically separating reactor coolant and process water flow data. The correlation between the calculated 7Q10 flows and the watershed areas for Four Mile Branch and Pen Branch agrees with that calculated by the USGS for Upper Three Runs and Lower Three Runs Creeks. The agreement between these two independent calculations lends confidence to the 7Q10 flow calculations presented in this report.
Date: October 1, 1996
Creator: Chen, K. F.
Partner: UNT Libraries Government Documents Department

Modeling acute health risks associated with accidental releases of toxic gases

Description: CHEM{_}MACCS has been developed from the radiological accident consequence code, MACCS, to perform probabilistic calculations of potential off-site consequences of the accidental atmospheric release of hazardous chemicals. The principal phenomena considered in CHEM{_}MACCS are atmospheric transport, mitigative actions based on dose projection, dose accumulation by a number of pathways, and early and latent health effects. CHEM{_}MACCS provides the following capabilities: (1) statistical weather sampling data (8,760 hourly data points per year), (2) population dose and health effect risk calculations based on site-specific population data, (3) health effects calculations including the consideration of potential site specific mitigative actions (evacuation and shielding), and (4) modeling of multiple release segments. Three different sample problems are contained in this report to show how to use CHEM{_}MACCS. Three test problems are run to compare CHEM{_}MACCS and D2PC. The doses versus the downwind centerline distances from the source for the given doses are in very close agreement.
Date: September 1, 1996
Creator: Haskin, F.E.; Ding, C.; Summa, K.J. & Young, M.
Partner: UNT Libraries Government Documents Department