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Unabated emission source term estimate for the 340-NX stack

Description: This document contains the sampling procedure, analytical results, and source term estimate from sampling work conducted on the main stack for the 340 Facility`s vault ventilation system. Several air filter and carbon cartridges were collected upstream of the KI off-gas control modules in order to determine the challenge source terms associated with various operating modes (e.g., under routine waste storage, during waste mixing, during waste transfer, etc.)
Date: March 19, 1997
Creator: Stordeur, R.T. & Glissmeyer, J.A., Fluor Daniel Hanford
Partner: UNT Libraries Government Documents Department

Machine-inudced backgrounds: their origin and loads on ATLAS/CMS

Description: A detailed analysis of machine-induced backgrounds (MIB) in the LHC collider detectors is performed with focus on origin and rates for three sources: tertiary beam halo, beam-gas interactions and kicker prefire. Particle fluxes originating from these operational and accidental beam losses are carefully calculated with the MARS15 code and presented at the entrance to the ATLAS and CMS experimental halls. It is shown that background rates in detector subsystems strongly depend on the origin of MIB, particle energy and type. Using this source term, instantaneous and integrated loads on the detectors and impact on the detector performance can be derived.
Date: May 1, 2008
Creator: Mokhov, N.V.; /Fermilab; Weiler, T. & /CERN
Partner: UNT Libraries Government Documents Department

A weighted adjoint-source for weight-window generation by means of a linear tally combination

Description: A new importance estimation technique has been developed that allows weight-window optimization for a linear combination of tallies. This technique has been implemented in a local version of MCNP and effectively weights the adjoint source term for each tally in the combination. Optimizing weight window parameters for the linear tally combination allows the user to optimize weight windows for multiple regions at once. In this work, we present our results of solutions to an analytic three-tally-region test problem and a flux calculation on a 100,000 voxel oil-well logging tool problem.
Date: January 1, 2009
Creator: Sood, Avneet; Booth, Thomas E & Solomon, Clell J
Partner: UNT Libraries Government Documents Department

Dynamic Data-Driven Event Reconstruction for Atmospheric Releases

Description: For atmospheric releases, event reconstruction answers the critical questions - How much material was released? When? Where? and What are the potential consequences? Inaccurate estimation of the source term can lead to gross errors, time delays during a crisis, and even fatalities. We are developing a capability that seamlessly integrates observational data streams with predictive models in order to provide the best possible estimates of unknown source term parameters, as well as optimal and timely situation analyses consistent with both models and data. Our approach utilizes Bayesian inference and stochastic sampling methods (Markov Chain and Sequential Monte Carlo) to reformulate the inverse problem into a solution based on efficient sampling of an ensemble of predictive simulations, guided by statistical comparisons with data.
Date: October 13, 2004
Creator: Sugiyama, G; Kosovic, B; Hanley, W; Johannesson, G; Larsen, S; Loosmore, G et al.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-SX-105: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-SX-105 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task.
Date: August 29, 1997
Creator: Kupfer, M.J.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-SX-111: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort,.an evaluation of available information for single-shell tank 241-SX-111 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task.
Date: August 29, 1997
Creator: Kupfer, M.J.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-SX-107: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-SX-107 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task.
Date: August 29, 1997
Creator: Kupfer, M.J.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-SX-106: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-SX-106 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task.
Date: August 29, 1997
Creator: Kupfer, M.J.
Partner: UNT Libraries Government Documents Department

From Molecular Dynamics to Kinetic Rate Theory: A Simple Example of Multiscale Modeling

Description: Radiation damage formation in iron has been investigated using the method of molecular dynamics simulation. The MD simulations have been used to determine primary defect production parameters for cascade energies up to 50 keV at temperatures from 100 to 900K. The energy dependence of these parameters has been used to determine appropriate neutron-energy-spectrum averaged damage production cross sections for various irradiation environments. Two applications of these effective cross sections are discussed. The first is an evaluation of neutron energy spectrum effects in commercial fission reactor pressure vessels. The second example deals with the use of these cross sections in the source term of a kinetic model used to predict void swelling and microstructural evolution. The simulation of the primary damage event by MD involves times less than 100 ps and a size scale of a few tens of nm, while the kinetic simulation encompasses several years and macroscopic sizes. This use of the MD results to develop an improved source term for rate theory modeling provides a simple example of multiscale modeling.
Date: November 30, 1998
Creator: Greenwood, L.R. & Stoller, R.E.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-TX-103: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-TX-103 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task. The best-basis inventory is based on an engineering assessment of waste type, process flowsheet data, early sample data, and/or other available information. The Standard Inventories of Chemicals and Radionuclides in Hanford Site Tank Wastes (Kupfer et al. 1997) describes standard methodology used to derive the tank-by-tank best-basis inventories. This preliminary TCR will be updated using this same methodology when additional data on tank contents become available.
Date: August 26, 1997
Creator: Hendrickson, D.W.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-TX-110: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-TX-110 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task.
Date: August 26, 1997
Creator: Place, D.E.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-TX-112: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-TX-112 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task. The best-basis inventory is based on an engineering assessment of waste type, process flowsheet data, early sample data, and other available information. The Standard Inventories of Chemicals and Radionuclides in Hanford Site Tank Wastes (Kupfer et al. 1997) describes standard methodology used to derive the tank-by-tank best-basis inventories. This preliminary TCR will be updated using this same methodology when additional data on tank contents become available.
Date: August 26, 1997
Creator: Place, D.E.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-TX-111: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-TX-111 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task. The best-basis inventory is based on an engineering assessment of waste type, process flowsheet data, early sample data, and/or other available information. The Standard Inventories of Chemicals and Radionuclides in Hanford Site Tank Wastes (Kupfer et al. 1997) describes standard methodology used to derive the tank-by-tank best-basis inventories. This preliminary TCR will be updated using this same methodology when additional data on tank contents become available.
Date: August 26, 1997
Creator: Place, D.E.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-SX-112: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-SX-112 was performed, and a best-basis, inventory was established. This work follows the methodology that was established by the standard inventory task.
Date: August 29, 1997
Creator: Kupfer, M.J.
Partner: UNT Libraries Government Documents Department

Verification of VENTSAR XL - a spreadsheet version of VENTSAR

Description: VENTSAR is a computer model that analyzes flow patterns of pollutants on or near buildings. Plume rise may be considered. VENTSAR has been modified to allow for execution on a Macintosh using Microsoft Excel. This new version is called VENTSAR XL. All methodologies are identical to those within VENTSAR. This report provides verification of all models within VENTSAR XL. Strict comparisons were made with VENTSAR to ensure consistency between the two models
Date: May 1, 1996
Creator: Simpkins, A.A.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-TX-106: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-TX-106 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task. The best-basis inventory is based on an engineering assessment of waste type, process flowsheet data, early sample data, and/or other available information. The Standard Inventories of Chemicals and Radionuclides in Hanford Site Tank Wastes (Kupfer et al. 1997) describes standard methodology used to derive the tank-by-tank best-basis inventories. This preliminary TCR will be updated using this same methodology when additional data on tank contents become available.
Date: August 26, 1997
Creator: Kupfer, M.J.
Partner: UNT Libraries Government Documents Department

Preliminary tank characterization report for single-shell tank 241-TX-114: Best-basis inventory

Description: An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-TX-114 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task. The best-basis inventory is based on an engineering assessment of waste type, process flowsheet data, early sample data, and other available information. The Standard Inventories of Chemicals and Radionuclides in Hanford Site Tank Wastes (Kupfer et al. 1997) describes standard methodology used to derive the tank-by-tank best-basis inventories. This preliminary TCR will be updated using this same methodology when additional data on tank contents become available.
Date: August 26, 1997
Creator: Place, D.E.
Partner: UNT Libraries Government Documents Department

Mechanistic facility safety and source term analysis

Description: A PC-based computer program was created for facility safety and source term analysis at Hanford The program has been successfully applied to mechanistic prediction of source terms from chemical reactions in underground storage tanks, hydrogen combustion in double contained receiver tanks, and proccss evaluation including the potential for runaway reactions in spent nuclear fuel processing. Model features include user-defined facility room, flow path geometry, and heat conductors, user-defined non-ideal vapor and aerosol species, pressure- and density-driven gas flows, aerosol transport and deposition, and structure to accommodate facility-specific source terms. Example applications are presented here.
Date: June 9, 1999
Creator: PLYS, M.G.
Partner: UNT Libraries Government Documents Department

Streamtube Fate and Transport Modeling of the Source Term for the Old Radioactive Waste

Description: The modeling described in this report is an extension of previous fate and transport modeling for the Old Radioactive Waste Burial Ground Corrective Measures Study/Feasibility Study. The purpose of this and the previous modeling is to provide quantitative input to the screening of remedial alternatives for the CMS/FS for this site.
Date: November 16, 2000
Creator: Brewer, K.
Partner: UNT Libraries Government Documents Department

OXIDATION OF INCONEL 718 IN AIR AT TEMPERATURES FROM 973K TO 1620K.

Description: As part of the APT project, it was necessary to quantify the release of tungsten from the APT spallation target during postulated accident conditions in order to develop accident source terms for accident consequence characterization. Experiments with tungsten rods at high temperatures in a flowing steam environment characteristic of postulated accidents revealed that considerable vaporization of the tungsten occurred as a result of reactions with the steam and that the aerosols which formed were readily transported away from the tungsten surfaces, thus exposing fresh tungsten to react with more steam. The resulting tungsten release fractions and source terms were undesirable and it was decided to clad the tungsten target with Inconel 718 in order to protect it from contact with steam during an accident and mitigate the accident source term and the consequences. As part of the material selection criteria, experiments were conducted with Inconel 718 at high temperatures to evaluate the rate of oxidation of the proposed clad material over as wide a temperature range as possible, as well as to determine the high-temperature failure limit of the material. Samples of Inconel 718 were inserted into a preheated furnace at temperatures ranging from 973 K to 1620 K and oxidized in air for varying periods of time. After oxidizing in air at a constant temperature for the prescribed time and then being allowed to cool, the samples would be reweighed to determine their weight gain due to the uptake of oxygen. From these weight gain measurements, it was possible to identify three regimes of oxidation for Inconel 718: a low-temperature regime in which the samples became passivated after the initial oxidation, an intermediate-temperature regime in which the rate of oxidation was limited by diffusion and exhibited a constant parabolic rate dependence, and a high-temperature regime in which material deformation ...
Date: October 1, 2000
Creator: GREENE,G.A. & FINFROCK,C.C.
Partner: UNT Libraries Government Documents Department

Source terms for plutonium aerosolization from nuclear weapon accidents

Description: The source term literature was reviewed to estimate aerosolized and respirable release fractions for accidents involving plutonium in high-explosive (HE) detonation and in fuel fires. For HE detonation, all estimates are based on the total amount of Pu. For fuel fires, all estimates are based on the amount of Pu oxidized. I based my estimates for HE detonation primarily upon the results from the Roller Coaster experiment. For hydrocarbon fuel fire oxidation of plutonium, I based lower bound values on laboratory experiments which represent accident scenarios with very little turbulence and updraft of a fire. Expected values for aerosolization were obtained from the Vixen A field tests, which represent a realistic case for modest turbulence and updraft, and for respirable fractions from some laboratory experiments involving large samples of Pu. Upper bound estimates for credible accidents are based on experiments involving combustion of molten plutonium droplets. In May of 1991 the DOE Pilot Safety Study Program established a group of experts to estimate the fractions of plutonium which would be aerosolized and respirable for certain nuclear weapon accident scenarios.
Date: July 1, 1995
Creator: Stephens, D.R.
Partner: UNT Libraries Government Documents Department

SCFA lead lab technical assistance at Lawrence Berkeley National Laboratory: Baseline review of three groundwater plumes

Description: During the closeout session, members of the technical assistance team conveyed to the site how impressed they were at the thoroughness of the site's investigation and attempts at remediation. Team members were uniformly pleased at the skilled detection work to identify sources, make quick remediation decisions, and change course when a strategy did not work well. The technical assistance team also noted that, to their knowledge, this is the only DOE site at which a world-class scientist has had primary responsibility for the environmental restoration activities. This has undoubtedly contributed to the successes observed and DOE should take careful note. The following overall recommendations were agreed upon: (1) The site has done a phenomenal job of characterization and identifying and removing source terms. (2) Technologies selected to date are appropriate and high impact, e.g. collection trenches are an effective remedial strategy for this complicated geology. The site should continue using technology that is adapted to the site's unique geology, such as the collection trenches. (3) The site should develop a better way to determine the basis of cleanup for all sites. (4) The sentinel well system should be evaluated and modified, if needed, to assure that the sentinel wells provide coverage to the current site boundary. Potential modifications could include installation, abandonment or relocation of wells based on the large amount of data collected since the original sentinel well system was designed. (5) Modeling to assist in remedial design and communication should continue. (6) The site should develop a plan to ensure institutional memory. (7) The most likely possibility for improving closure to 2006 is by removing the residual source of the Old Town plume and establishing the efficacy of remediation for the 51/64 plume.
Date: September 26, 2002
Creator: Hazen, Terry; Evans, John C.; Looney, Brian B.; Phelps, Tommy J. & Sullivan, Terry
Partner: UNT Libraries Government Documents Department

Annual Report submitted on the PNNL portion of EMSP Project No. 86729

Description: A migration-resistant fraction (MRF) is a portion of a polluted sediment's contaminant inventory that exhibits slow release. Slow release is a key process that controls organic contaminant transport and fate in a plume long after the major portion of the contaminant inventory of a source term has been depleted or removed. Slow release rates are not well understood nor are they commonly accounted for in subsurface numerical transport models. In this project, we propose to study the accumulation and slow-release behavior of carbon tetrachloride (CCl4) MRF as a function of time, contaminant concentration and different physicochemical properties of sediments. Both model materials that mimic the physical/chemical properties of sediments and natural sediments will be used in project studies. Experiments will be conducted at macro- and microscopic scales under both unsaturated (Washington State University-WSU) and saturated conditions (Pacific Northwest National Laboratory-PNNL). The results will be used to (1) develop a mechanistic description of slow release of CCl4 in the subsurface environment and (2) lay the groundwork for improving the robustness of numerical models that predict organic contaminant transport and fate under natural conditions. The outcomes of this study are expected to improve the conceptual model of CCl4 subsurface transport and fate at different physical scales and have an impact on remediation and site closure decision-making at Department of Energy (DOE) sites, especially in situations involving the potential application of natural attenuation. This report summarizes work performed on the PNNL component of the project after the first 8 months of a three-year project. Progress on the WSU component of the project is addressed under a separate annual report submission.
Date: June 1, 2003
Creator: Riley, Robert; Amonette, James & Peyton, Brent
Partner: UNT Libraries Government Documents Department

How might a statistical cloud scheme be coupled to a mass-flux convection scheme?

Description: The coupling of statistical cloud schemes with mass-flux convection schemes is addressed. Source terms representing the impact of convection are derived within the framework of prognostic equations for the width and asymmetry of the probability distribution function of total water mixing ratio. The accuracy of these source terms is quantified by examining output from a cloud resolving model simulation of deep convection. Practical suggestions for inclusion of these source terms in large-scale models are offered.
Date: September 27, 2004
Creator: Klein, Stephen A.; Pincus, Robert; Hannay, Cecile & Xu, Kuan-man
Partner: UNT Libraries Government Documents Department