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PAT-1 safety analysis report addendum

Yoshimura, Richard H.; Morrow, Charles W.; Weiner, Ruth F.; Harding, David C.; Heitman, Lili A.; Kalan, Robert K.; Lopez Mestre, Carlos L.; Miller, David R.; Schmale, David T.; Knorovsky, Gerald A.

The Plutonium Air Transportable Package, Model PAT-1, is certified under Title 10, Code of Federal Regulations Part 71 by the U.S. Nuclear Regulatory Commission (NRC) per Certificate of Compliance (CoC) USA/0361B(U)F-96 (currently Revision 9). The purpose of this SAR Addendum is to incorporate plutonium (Pu) metal as a new payload for the PAT-1 package. The Pu metal is packed in an inner container (designated the T-Ampoule) that replaces the PC-1 inner container. The documentation and results from analysis contained in this addendum demonstrate that the replacement of the PC-1 and associated packaging material with the T-Ampoule and associated packaging with the addition of the plutonium metal content are not significant with respect to the design, operating characteristics, or safe performance of the containment system and prevention of criticality when the package is subjected to the tests specified in 10 CFR 71.71, 71.73 and 71.74.

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PAT-1 safety analysis report addendum author responses to request for additional information

Yoshimura, Richard H.; Knorovsky, Gerald A.; Morrow, Charles W.; Weiner, Ruth F.; Harding, David C.; Heitman, Lili A.; Lopez Mestre, Carlos L.; Kalan, Robert K.; Miller, David R.; Schmale, David T.

The Plutonium Air Transportable Package, Model PAT-1, is certified under Title 10, Code of Federal Regulations Part 71 by the U.S. Nuclear Regulatory Commission (NRC) per Certificate of Compliance (CoC) USA/0361B(U)F-96 (currently Revision 9). The National Nuclear Security Administration (NNSA) submitted SAND Report SAND2009-5822 to NRC that documented the incorporation of plutonium (Pu) metal as a new payload for the PAT-1 package. NRC responded with a Request for Additional Information (RAI), identifying information needed in connection with its review of the application. The purpose of this SAND report is to provide the authors responses to each RAI. SAND Report SAND2010-6106 containing the proposed changes to the Addendum is provided separately.

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A stress-state modified strain based failure criterion for evaluating the structural integrity of an inner eutectic barrier

Heitman, Lili A.; Yoshimura, Richard H.; Miller, David R.

A slight modification of a package to transport solid metal contents requires inclusion of a thin titanium liner to protect against possible eutectic formation in 10 CFR 71.74 regulatory fire accident conditions. Under severe transport regulatory impact conditions, the package contents could impart high localized loading of the liner, momentarily pinching it between the contents and the thick containment vessel, and inducing some plasticity near the contact point. Actuator and drop table testing of simulated contents impacts against liner/containment vessel structures nearly bounded the potential plastic strain and stress triaxiality conditions, without any ductile tearing of the eutectic barrier. Additional bounding was necessary in some cases beyond the capability of the actuator and drop table tests, and in these cases a stress-modified evolution integral over the plastic strain history was successfully used as a failure criterion to demonstrate that structural integrity was maintained. The Heaviside brackets only allow the evolution integral to accumulate value when the maximum principal stress is positive, since failure is never observed under pure hydrostatic pressure, where the maximum principal stress is negative. Detailed finite element analyses of myriad possible impact orientations and locations between package contents and the thin eutectic barrier under regulatory impact conditions have shown that not even the initiation of a ductile tear occurs. Although localized plasticity does occur in the eutectic barrier, it is not the primary containment boundary and is thus not subject to ASME stress allowables from NRC Regulatory Guide 7.6. These analyses were used to successfully demonstrate that structural integrity of the eutectic barrier was maintained in all 10 CFR 71.73 and 71.74 regulatory accident conditions. The NRC is currently reviewing the Safety Analysis Report.

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Overview of sensors and needs for environmental monitoring

Proposed for publication in Sensors.

Ho, Clifford K.; Robinson, Alex L.; Miller, David R.

This paper surveys the needs associated with environmental monitoring and long-term environmental stewardship. Emerging sensor technologies are reviewed to identify compatible technologies for various environmental monitoring applications. The contaminants that are considered in this report are grouped into the following categories: (1) metals, (2) radioisotopes, (3) volatile organic compounds, and (4) biological contaminants. United States regulatory drivers are evaluated for different applications (e.g., drinking water, storm water, pretreatment, and air emissions), and sensor requirements are derived from these regulatory metrics. Sensor capabilities are then summarized according to contaminant type, and the applicability of the different sensors to various environmental monitoring applications is discussed.

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Sensors for environmental monitoring and long-term environmental stewardship

Ho, Clifford K.; Robinson, Alex L.; Miller, David R.

This report surveys the needs associated with environmental monitoring and long-term environmental stewardship. Emerging sensor technologies are reviewed to identify compatible technologies for various environmental monitoring applications. The contaminants that are considered in this report are grouped into the following categories: (1) metals, (2) radioisotopes, (3) volatile organic compounds, and (4) biological contaminants. Regulatory drivers are evaluated for different applications (e.g., drinking water, storm water, pretreatment, and air emissions), and sensor requirements are derived from these regulatory metrics. Sensor capabilities are then summarized according to contaminant type, and the applicability of the different sensors to various environmental monitoring applications is discussed.

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In-Situ Radiation Detection Demonstration Final Report

Mohagheghi, Amir H.; Miller, David R.; Miller, Mark L.; Miller, David R.

The Department of Defense (DoD) has hundreds of facilities where radioactive materials have been used or are being used, including firing ranges, low-level radioactive waste disposal areas, and areas where past activities have resulted in environmental contamination. Affected sites range in size from a few acres to square miles. Impact to the DoD comes through military base closure and release to the public. It is important that radioactive contaminants are remediated to levels that result in acceptable risk to the public. Remediation requires characterization studies, e.g., sampling and surveys, to define the affected areas, removal actions, and final confirmatory sampling and surveys. Characterization of surface contamination concentrations has historically been performed using extensive soil sampling programs in conjunction with surface radiation surveys conducted with hand-held radiation monitoring equipment. Sampling is required within the suspect affected area and a large buffer area. Surface soil contaminant characterization using soil sampling and hand held monitoring are costly, time consuming, and result in long delays between submission of samples for analysis and obtaining of final results. This project took an existing, proven radiation survey technology that has had limited exposure and improved its capabilities by documenting correlation factors for various detector/radionuclide geometries that commonly occur in field surveys. With this tool, one can perform characterization and final release surveys much more quickly than is currently possible, and have detection limits that are as good as or better than current technology. This paper will discuss the capabilities of a large area plastic scintillation detector used in conjunction with a global positioning system (GPS) to improve site characterization, remediation, and final clearance surveys of the radioactively contaminated site. Survey results can rapidly identify areas that require remediation as well as guide surgical removal of contaminated soil that is above remediation guidelines. Post-remediation surveys can document that final radiological site conditions are within the remedial action limits.

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Natural attenuation assessment of multiple VOCs in a deep vadose zone

Miller, David R.; Miller, David R.

The fate of six volatile organic compounds (VOC) in a 150-meter deep vadose zone was examined in support of a RCRA Corrective Measures Study of the Chemical Waste Landfill at Sandia National Laboratories, Albuquerque, New Mexico. The study focused on the modeling of potential future transport of the VOCs to exposure media upon the completion of two separate voluntary corrective measures--soil vapor extraction and landfill excavation--designed to significantly reduce contaminant levels in subsurface soils. modeling was performed with R-UNSAT, a finite-difference simulator that was developed by the U.S. Geological Survey. R-UNSAT facilitated a relatively unique and comprehensive assessment of vapor transport because it (1) simulated the simultaneous movement of all six VOCs, taking into account each constituent's diffusion coefficient as affected by its mole fraction within a mixture of chemicals, and (2) permitted simultaneous assessment of risk to human health via volatilization (air) and drinking water (groundwater) pathways. Modeling results suggested that monitored natural attenuation would represent a viable remedial alternative at the landfill after both voluntary corrective measures were completed.

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29 Results
29 Results