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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 433 records · Page 24

DOE-STD-1112-2019 Review for the 2020 DOELAP Radiobioassy Program Assessment

In compliance with DOE-STD-1112-2019 section 4.6(i) and in preparation for a 2020 DOELAP assessment of Radiobioassay Program, the QA officer, WBC/SLAB Group Leader, BLAB/RML Group Leader, and WBC/SLAB Health Physicists reviewed the program’s performance in accordance with the criteria found in DOE-STD-1112-2019 and in the accompanying checklist provided to the DOELAP assessor community in January 2020.

61 RADIATION PROTECTION AND DOSIMETRY↗

Plutonium workers get a new level of education in the actinide mission

The Associate Laboratory Directorate for Weapons Production (ALDWP) and the National Security Education Center (NSEC) have teamed to develop a new Nuclear Enterprise Science and Technology (NEST) Academic Certificate program offered through the University of New Mexico – Los Alamos (UNM-LA). The pilot program, which virtually kicked off on January 19 even amidst snow closures, received accreditation by the State Higher Education Department (HED) in FY20 and is designed for LANL’s existing fissile material handler technician and technologist employee workforce. It will provide essential science, operations, and business education on all aspects of working in modern nuclear materials handling and processing facilities. The first course for the certificate program is called “Nuclear Facility Fundamentals.” A call for nominations went out to the directorate and a cohort of 15 individuals has been established to start the program.

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2019 ASER Supplemental Tables Chapters 7 and 8

This pdf contains the data tables that will be posted on the LANL external website as a supplement to the Los Alamos National Laboratory 2019 Annual Site Environmental Report for Chapters 7 and 8.

54 ENVIRONMENTAL SCIENCES↗

NEST Lectures [PowerPoint]

The presentation is composed of the slides used in various NEST lectures including: Interaction of Radiation with Matter, Biological and Health Effects of Radiation Exposure, Radionuclide Detection and Dose Assessment, Plutonium, Other Radionuclides Monitored by Bioassay and Case Studies, and, Counting Statistics.

61 RADIATION PROTECTION AND DOSIMETRY↗

A Technical basis for in-house calibration of 252 Cf neutron source emission rates

10CFR835 stipulates that radiation protection instruments must be calibrated at least annually. Accordingly, calibration of dose rate instruments are reliant on well-known reference fields. The neutron-free-in-air facility (NFIA) located at TA36-0214 provides such a capability for neutron remmeters. One of the reference NFIA sources, 252 Cf, must be replaced every 8-10 years due to its relatively short half-life (2.645 ± 0.008 y). In the past, each newly purchased 252 Cf source has been calibrated at NIST using the Mn-bath technique prior to shipping to LANL. However, because of COVID-19 complications, the most recently acquired 252 Cf source (FTC-CF-7167) has been stored at LANL pending approval to ship to NIST for calibration. Due to the considerable expense in transporting the source to and from NIST, this TBD was written to demonstrate that new sources can be accurately calibrated via intercomparison measurements with older NIST-calibrated 252 Cf sources. It had been previously noted that such measurements yielded emission rates that agreed very well with the official rates established by NIST

252cf↗

(U) Segmented Scintillator Pitch, Thickness, and Septa Material Effects on the Swank Factor, Quantum Efficiency, and DQE(0) for High-Energy X-Ray Radiography

Scintillator design is an important aspect in constructing a radiographic facility in order to collect the most robust data possible. For the proposed Enhanced Capabilities for Sub-critical Experiment (ECSE) facility in Nevada, we explored a permutation of 13 segmented scintillator designs in order to understand the best performance and trade offs for each design. We calculated the quantum efficiency, Swank factor, and detective quantum efficiency at zero-frequency (DQE(0)) for each scintillator design in order to compare performance.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Analysis of Air-Purifying Respirator (APR) Cartridge Performance Testing on Hanford Tanks SX-101 and SX-104 (Vol.1)

Washington River Protection Solutions (WRPS) conducted tests on two types of chemical cartridges for use in air-purifying respirators to determine the period of time that the cartridges would provide adequate performance1 to protect workers when exposed to a mixture of Chemicals of Potential Concern (COPC) from vapors exiting the headspaces of Hanford tanks SX-101 and SX-104. The Occupational Safety and Health Administration (OSHA) considers cartridge testing a valid approach for establishing cartridge change schedules.2 Testing is commonly applied in situations where mixtures of COPCs exist and where other approaches such as manufacturer recommendations and modeling are less reliable. The tests were designed and conducted to ensure measurement and/or control of the key variables OSHA identified as important to estimate the cartridge service life, including temperature, humidity, COPC concentration, breathing rate, and cartridge adsorption capacity. Testing was conducted from June 16-17, 2017, and June 23-24, 2017, using headspace vapors from Hanford tank SX-104 and Hanford tank SX-101, respectively. Headspace vapors under static conditions were fed to a respirator cartridge test stand developed by WRPS in collaboration with HiLine Engineering (Richland, Washington). Multipurpose respirator cartridges, SCOTT 7422-SD1 and SCOTT 7422-SC1 (SCOTT Safety, Monroe, North Carolina), were assessed on separate days. Sample media (sorbent tubes) were used to collect samples of the vapor stream entering and exiting the respirator cartridges, and subsequently were analyzed for COPC concentrations. Pacific Northwest National Laboratory was tasked with conducting an independent analysis of the analytical results and making recommendations based on the results for respiratory cartridge performance and service life.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

ADETS User Manual

ADETS (Automated DEpletion Transport System) calculates coupled neutronic/isotopic results for nuclear systems and produces a large number of criticality and burnup results based on various material feed/removal specifications, power(s), and time intervals. ADETS is a fully automated tool that links the LANL MCNP Monte Carlo transport code with the SCALE system, specifically ORIGEN-ARP (radioactive decay and burnup code). Additionally, ADETS can compute the dose at various distances of the reactor using a point gamma source, whose characteristics are computed by ORIGEN-ARP. In addition, ADETS is fully coupled with the Uncertanty Quantification, Probabilistic Risk Assessment, Parameter Optimization and Data Analysis code RAVEN (developed at the Idaho National Laboratory as well). RAVEN is released with ADETS but MCNP and SCALE (ORIGEN-ARP) are not included.

42 ENGINEERING↗

Modeling Explosive Dispersal of Radiological Material: A Nonparametric Analysis

The National Atmospheric Release Advisory Center (NARAC) is a Department of Energy (DOE) asset that provides guidance on the potential effects of atmospherically released hazards based on dispersion simulation results. Numerical simulation results are compared to well-characterized experimental measurements whenever possible to validate and refine the model predictions. In 2012, such measurements were obtained by Defence Research and Development Canada (DRDC) and collaborating organizations for the case of explosively released 140 La – a radioactive isotope with a half-life of 1.6781 days.

42 ENGINEERING↗

Liquid Metal Intrusion Testing Final Report

Los Alamos National Lab (LANL) is concerned about potential interactions between a tin-antimony pewter material used for localized radiation shielding and stainless-steel containers used for storage and movement of radioactive materials when containers are subjected to elevated temperatures. The specific concern is whether pewter constituents can diffuse into grain boundaries and lead to embrittlement of the stainless steel, potentially compromising the ability of stainless steel components to maintain containment. This work will provide a qualitative and quantitative understanding of the depth of penetration of the pewter coating constituents into stainless steel when the test coupons are subjected to a range of thermal environments. The results of the present work will allow LANL to determine conditions for safely using the pewter lined containers.

36 MATERIALS SCIENCE↗

Preliminary Design of a New Pulsed-Neutron Die-Away Experimental Testbed for Thermal Scattering Law Benchmarks (PNDA) (IER-501 CED-1)

This report presents the preliminary design (CED-1) of IER-501, a new testbed for pulsed-neutron die-away (PNDA) experiments at Lawrence Livermore National Laboratory (LLNL). The PNDA experiments will be high-quality benchmarks that serve to optimize and validate thermal scattering laws (TSLs), which are high-priority nuclear data for the Department of Energy’s Criticality Safety Program (NCSP). PNDA experiments can be used to generate nuclear data validation benchmarks quickly and cheaply, as they do not require fissile material or a nuclear facility to conduct them.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

LANL Environmental ALARA Program Status Report for CY 2020

Los Alamos National Laboratory (LANL) ensures that radiation exposures to members of the public and the environment from LANL operations, past and present, are below regulatory thresholds and are as low as reasonably achievable (ALARA) through compliance with Department of Energy (DOE) Order 458.1 Radiation Protection for the Public and the Environment (DOE 2020), and LANL Functional Series Documents EPC-ES-FSD-004,Environmental Radiation Protection, (LANL 2020a) and EPC-ES-FSD-003, Los Alamos National Laboratory Environmental ALARA Program (LANL 2020b). These documents provide related program authorities, responsibilities, descriptions, processes, and thresholds for conducting qualitative and quantitative ALARA analyses for prospective and actual radiation exposures to the public and to the environment resulting from DOE activities conducted on the LANL site.

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Validation of the Public Radiation Exposure Calculation for the Incident at the National Institute of Standards and Technology Center for Neutron Research on February 3, 2021

The Department of Energy/National Nuclear Security Administration Consequence Management Program was contacted by the Health Physics Chief of the National Institute of Standards and Technology Center for Neutron Research (NCNR) to review public radiation exposure calculations for an event that occurred on its Gaithersburg, Maryland, campus on February 3, 2021. Subject matter experts from the Nuclear Emergency Support Team (NEST) assets, specifically the Consequence Management Home Team (CMHT) and the National Atmospheric Release Advisory Center (NARAC), were selected to provide support. CMHT used three separate modeling codes to validate the results the scientists at NCNR calculated using the HotSpot model. The analyses were performed using NARAC’s in-house Lagrangian dispersion codes known as LODI and Aeolus, as well as the Turbo FRMAC software from Sandia National Laboratories. The team used parameters provided by the NCNR scientists regarding the site, applicable observable meteorological data, and environmental survey and sampling data to estimate public exposure. Each model estimated public dose at much less than 0.5 mrem. CMHT concurs with the NCNR public radiation exposure calculations which state that members of the public at the 400-meter boundary would have received a radiological dose of less than 0.5 mrem.

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TCR Postulated Accident and MHA Dose Assessment

Oak Ridge National Laboratory (ORNL) is engaged in regulatory activities to gain US Department of Energy (DOE) approval to build and operate a small high-temperature gas reactor, the Transformational Challenge Reactor (TCR). ORNL uses advanced manufacturing techniques to produce select reactor components. The TCR is unique in its mission: the reactor’s at-power operating lifetime will be less than one effective full-power day to limit the radiological source term to very low values, thus facilitating approval to operate. The primary regulatory documents governing construction and operation of the facility are NUREG-1537, “Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors” and DOE-STD-3009, “Preparation of Nonreactor Nuclear Facility Documented Safety Analysis.” Although this document is not a safety basis document, it provides a conservative indication of the magnitude of onsite and offsite radiological doses for specific scenarios, thus informing future design and regulatory activities. As required by NUREG-1537, scenarios included in this analysis are (1) a worstcase depressurized loss-of-forced-circulation accident, and (2) a maximum hypothetical accident. Details on the analysis of dose consequences with various system configurations are also provided.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Radiation Detection Data Competition Report

In FY2018 through FY2020, NA-22, the Defense Nuclear Nonproliferation Research and Development Program, funded a Data Science project to develop and implement statistical methodology to effectively host data competitions with the goal of leveraging the opportunity provided by crowdsourcing. By accessing and engaging expertise from a broader research community, there is an opportunity to attract innovative solutions from a variety of different research disciplines to advance the ability to solve important non-proliferation problems. This report summarizes the key results of this project after hosting two data competitions focused on urban radiation detection. The first competition was focused on attracting participants from the U.S. national laboratories, while the second, hosted by TopCoder, was open to the broader international community and awarded prize money to the top 10 competitors. At the start of the project, there was strong interest from NA-22 to explore and develop the capability to host data competitions as a means of leveraging the broader community to solve important nuclear nonproliferation problems. Having a standard data set on which to compare different approaches based on clearly defined criteria was desirable to be able to evaluate the state of solutions for important problems. Initially, it was not clear that it would even be possible logistically and bureaucratically to host a competition with an international field of competitors and to award the prize money needed to attract solutions from top competitors. Happily, a path to host the competitions was ultimately found that allowed this powerful accelerator of improvements to be leveraged.

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