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Economics of the specification 6M safety re-evaluation and regulatory requirements

Description: The objective of this work was to examine the potential economic impact of the DOT Specification 6M criticality safety re-evaluation and regulatory requirements. The examination was based upon comparative analyses of current authorized fissile material load limits for the 6M, current Federal regulations (and interpretations) limiting the contents of Type B fissile material packages, limiting aggregates of fissile material packages, and recent proposed fissile material mass limits derived from s… more
Date: January 1, 1985
Creator: Hopper, C. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Criticality safety study of the MSRE Fuel Drain Tank Cell in Building 7503

Description: This report provides a criticality safety study of the molten salt reactor fuel currently being stored in the Fuel Drain Tank (FDT) Cell of the Molten Salt Reactor Experiment (MSRE) facility (Building 7503) located in the Melton Valley area of the Oak Ridge National Laboratory. The FDTs contain approximately 36 kg of uranium consisting primarily of {sup 233}U, some plutonium, and fission products in a solidified fluoride salt mixture. The nominal composition of the fluoride salt mixture in the … more
Date: January 1, 1994
Creator: Hollenbach, D. F. & Hopper, C. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An updated nuclear criticality slide rule

Description: This Volume 2 contains the functional version of the updated nuclear criticality slide rule (more accurately, sliding graphs) that is referenced in An Updated Nuclear Criticality Slide Rule: Technical Basis, NUREG/CR-6504, Vol. 1 (ORNL/TM-13322/V1). This functional slide rule provides a readily usable {open_quotes}in-hand{close_quotes} method for estimating pertinent nuclear criticality accident information from sliding graphs, thereby permitting (1) the rapid estimation of pertinent criticalit… more
Date: April 1, 1998
Creator: Hopper, C. M. & Broadhead, B. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Potential for and consequences of criticality resulting from hydrogeochemically concentrated fissile uranium blended with soil in low-level waste disposal facilities

Description: Evaluations were done to determine conditions that could permit nuclear criticality with fissile uranium in low-level-waste (LLW) facilities and to estimate potential radiation exposures to personnel if there were such an accident. Simultaneous hydrogeochemical and nuclear criticality studies were done (1) to identify some realistic scenarios for uranium migration and concentration increase at LLW disposal facilities, (2) to model groundwater transport and subsequent concentration via sorption … more
Date: August 1, 1997
Creator: Hopper, C. M. & Parks, C. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Criticality safety considerations for low-level-waste facilities

Description: The nuclear criticality safety for handling and burial of certain special nuclear materials (SNM) at low-level-waste (LLW) facilities is licensed by the US Nuclear Regulatory Commission (NRC). Recently, Oak Ridge National Laboratory (ORNL) staff assisted the NRC Office of Nuclear Material Safety and Safeguards, Low-Level-Waste and Decommissioning Projects Branch, in developing technical specifications for the nuclear criticality safety of {sup 235}U and {sup 235}Pu in LLW facilities. This assis… more
Date: April 1995
Creator: Hopper, C. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Expanded and applied sixteen neutron-energy-group cross-section library

Description: The purpose of this work was fivefold: to develop an expanded neutron cross-section library containing approximately 1200 cross-section sets with the Hansen-Roach (H-R) sixteen neutron-energy-group structure; to provide an enhanced computational tool on a personal computer for criticality calculations; to provide consistent values of the effective scattering cross sections (sigma-s) for each set of the expanded H-R library, for selecting the resonance self-shielded cross sections (sigma-p); to … more
Date: January 1, 1990
Creator: Hopper, C. M. & Renier, J. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Criticality safety study of the MSRE auxiliary charcoal bed

Description: The Molten Salt Reactor Experiment (MSRE) was operated from June 1965 to December 1969. The objective of the experiment was to investigate the practicality of developing a power reactor consisting of a graphite lattice with circulating molten uranium salt as fuel for application in central power stations. When the experiment was terminated in 1969, approximately 4710 kg of salt containing approximately 36.3 kg of uranium, 675 g of plutonium, and various fission products were transferred to two … more
Date: September 1, 1996
Creator: Hollenbach, D. F. & Hopper, C. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Verification of criticality accident alarm system for environmental restoration activities

Description: This work analyzes the optimal placement of a criticality accident alarm system (CAAS) necessitated by an unexpected accumulation of fissile materials in the filtration system of an idled experimental nuclear reactor. Results using multidimensional deterministic and Monte Carlo methods confirmed the suitability of an existing CAAS placement located in the adjacent reactor building.
Date: September 1, 1995
Creator: Broadhead, B. L.; Childs, R. L. & Hopper, C. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Assessment and recommendations for fissile-material packaging exemptions and general licenses within 10 CFR Part 71

Description: This report provides a technical and regulatory assessment of the fissile material general licenses and fissile material exemptions within Title 10 of the Code of Federal Regulations Part 71. The assessment included literature studies and calculational analyses to evaluate the technical criteria; review of current industry practice and concerns; and a detailed evaluation of the regulatory text for clarity, consistency and relevance. Recommendations for potential consideration by the Nuclear Reg… more
Date: July 1, 1998
Creator: Parks, C. V.; Hopper, C. M. & Lichtenwalter, J. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The potential for criticality following disposal of uranium at low-level waste facilities: Uranium blended with soil

Description: The purpose of this study was to evaluate whether or not fissile uranium in low-level-waste (LLW) facilities can be concentrated by hydrogeochemical processes to permit nuclear criticality. A team of experts in hydrology, geology, geochemistry, soil chemistry, and criticality safety was formed to develop achievable scenarios for hydrogeochemical increases in concentration of special nuclear material (SNM), and to use these scenarios to aid in evaluating the potential for nuclear criticality. Th… more
Date: June 1, 1997
Creator: Toran, L. E.; Hopper, C. M. & Naney, M. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Criticality safety studies for the storage of waste from nuclear fuel service in Intercell Storage Wells 2 and 3 of Building 3019

Description: This report provides computational evaluation results demonstrating that mixed oxide waste can be safely stored in Intercell Storage Wells 2 and 3 of Building 3019 at the Oak Ridge National Laboratory. Existing, verified computational techniques are validated with applicable critical experiments and tolerance limits for safety analyses are derived. Multiplication factors for normal and credible abnormal configurations are calculated and found to be far subcritical when compared to derived safet… more
Date: November 1, 1992
Creator: Primm, R. T., III; Hopper, C. M. & Smolen, G. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Criticality safety studies for the storage of waste from nuclear fuel service in Intercell Storage Wells 2 and 3 of Building 3019

Description: This report provides computational evaluation results demonstrating that mixed oxide waste can be safely stored in Intercell Storage Wells 2 and 3 of Building 3019 at the Oak Ridge National Laboratory. Existing, verified computational techniques are validated with applicable critical experiments and tolerance limits for safety analyses are derived. Multiplication factors for normal and credible abnormal configurations are calculated and found to be far subcritical when compared to derived safet… more
Date: November 1, 1992
Creator: Primm, R. T., III; Hopper, C. M. & Smolen, G. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Proposed Methodology for Establishing Area of Applicability

Description: This paper presents the application of sensitivity and uncertainty (S/U) analysis methodologies to the data validation tasks of a criticality safety computational study. The S/U methods presented are designed to provide a formal means of establishing the area (or range) of applicability for criticality safety data validation studies. The development of parameters that are analogous to the standard trending parameters form the key to the technique. These parameters are the so-called D parameters… more
Date: September 20, 1999
Creator: Broadhead, B. L.; Hopper, C. M. & Parks, C. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Criticality safety considerations for MSRE fuel drain tank uranium aggregation

Description: This paper presents the results of a preliminary criticality safety study of some potential effects of uranium reduction and aggregation in the Molten Salt Reactor Experiment (MSRE) fuel drain tanks (FDTs) during salt removal operations. Since the salt was transferred to the FDTs in 1969, radiological and chemical reactions have been converting the uranium and fluorine in the salt to UF{sub 6} and free fluorine. Significant amounts of uranium (at least 3 kg) and fluorine have migrated out of th… more
Date: March 1, 1997
Creator: Hollenbach, D. F. & Hopper, C. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Application of Covariance Data to Criticality Safety Data Validation

Description: The use of cross-section covariance data has long been a key part of traditional sensitivity and uncertainty analyses (S/U). This paper presents the application of S/U methodologies to the data validation tasks of a criticality safety computational study. The S/U methods presented are designed to provide a formal means of establishing the area (or range) of applicability for criticality safety data validation studies. The goal of this work is to develop parameters that can be used to formally d… more
Date: November 13, 1999
Creator: Broadhead, B. L.; Hopper, C. M. & Parks, C. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design Parameters for a Natural Uranium UO{sub 3} or U{sub 3}O{sub 8} Fueled Nuclear Reactor

Description: A recent Oak Ridge National Laboratory report provided preliminary analyses to propose alternative design parameters for a nuclear reactor that could be fueled with natural UO{sub 3} or U{sub 3}O{sub 8} and moderated with either heavy water or reactor-grade graphite. This report provides more specific reactor design and operating parameters for a heavy water-moderated reactor only. The basic assumptions and analytical approach are discussed together with the results of the analysis.
Date: November 15, 2002
Creator: Hopper, C. M.; Petrie, L. M.; Ott, L. J. & Parks, C. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Criticality safety criteria for license review of low-level waste facilities

Description: The handling and burial of specified quantities of special nuclear material (SNM) at low-level-waste (LLW) facilities require a license from the Nuclear Regulatory Commission (NRC). With assistance from Oak Ridge National Laboratory (ORNL) staff, the NRC Office of Nuclear Material Safety and Safeguards, Low-Level-Waste and Decommissioning Projects Branch, has developed technical specifications for the nuclear criticality safety of {sup 235}U and {sup 239}Pu in LLW facilities. The objective of t… more
Date: March 1, 1995
Creator: Hopper, C. M.; Odegaarden, R. H.; Parks, C. V. & Fox, P. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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 … more
Date: September 20, 1999
Creator: Broadhead, B. L.; Childs, R. L.; Hopper, C. M. & Parks, C. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Isotopic dilution of {sup 233}U with depleted uranium for criticality safety in processing and disposal

Description: The disposal of excess {sup 233}U as waste is being considered. Because {sup 233}U is a fissile material, a key requirement for processing {sup 233}U to a final waste form and disposing of it is the avoidance of nuclear criticality. For many processing and disposal options, isotopic dilution is the most feasible and preferred option to avoid nuclear criticality. Isotopic dilution is dilution of fissile {sup 233}U with nonfissile {sup 238}U. The use of isotopic dilution removes any need to contr… more
Date: July 1, 1997
Creator: Hopper, C. M.; Wright, R. Q.; Elam, K. R. & Forsberg, C. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Criticality benchmark guide for light-water-reactor fuel in transportation and storage packages

Description: This report is designed as a guide for performing criticality benchmark calculations for light-water-reactor (LWR) fuel applications. The guide provides documentation of 180 criticality experiments with geometries, materials, and neutron interaction characteristics representative of transportation packages containing LWR fuel or uranium oxide pellets or powder. These experiments should benefit the U.S. Nuclear Regulatory Commission (NRC) staff and licensees in validation of computational method… more
Date: March 1, 1997
Creator: Lichtenwalter, J. J.; Bowman, S. M.; DeHart, M. D. & Hopper, C. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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EMSP project summary (Project ID: 60077): Development of nuclear analysis capabilities for DOE waste management activities

Description: The objective of this project is to develop and demonstrate prototypical analysis capabilities that can be used by nuclear safety analysis practitioners to: (1) demonstrate a more thorough understanding of the underlying physics phenomena that can lead to improved reliability and defensibility of safety evaluations; and (2) optimize operations related to the handling, storage, transportation, and disposal of fissile material and DOE spent fuel. To address these problems, this project has been i… more
Date: February 1, 2000
Creator: Parks, C. V.; Rearden, B. T.; DeHart, M. D.; Broadhead, B. L.; Hopper, C. M. & Petrie, L. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Dose consequences from a postulated criticality occurring in a low-level waste disposal facility

Description: Evaluations were done to determine conditions that could permit nuclear criticality with fissile uranium in low-level waste (LLW) facilities and to estimate potential radiation exposures to personnel if there were such an accident. Simultaneous hydrogeochemical and nuclear criticality studies were done (1) to identity realistic scenarios for uranium migration and concentration increase at LLW disposal facilities, (2) to model groundwater transport of uranium and subsequent concentration via sor… more
Date: December 1, 1997
Creator: Broadhead, B. L.; Childs, R. L.; Hopper, C. M. & Parks, C. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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