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This drill is designed to give players the opportunity to practice/train on response strategies, actions, and processes for responding to a given simulated emergency at TA-60-0017 in an open, no fault environment. This drill is also an opportunity to train or practice on the use of new procedures, equipment, or systems, or validate new policies/procedures.
The purpose of this briefing is to provide drill information to players participating in the TA-60-0017 Operations Based Emergency Drill as follows: Communicate general drill information and conduct expectations; Outline roles and responsibilities; and Provide safely and securely guidance to ensure unsafe act or security violation does not occur during the drill.
The first floor of the Radiological Laboratory/Utility/Office Building at TA-55, known as RLUOB (roo-lob) or Plutonium Facility-400 (PF-400), will soon become a bustling and dynamic space as employees and programs increase their work scope thanks to the new hazard category 3 designation. On Feb. 7, NNSA gave the final stamp of approval designating RLUOB as a hazard category 3 (HC-3) nuclear facility. RLUOB has been designated as a radiological facility (less than HC-3) since 2013, when the first phase of RLUOB Equipment Installation was completed. HC-3 is a level up in facility hazard category, a major effort to support the national security mission.
Environmental Protection and Compliance, Environmental Stewardship (EPC-ES) has evaluated radiological process knowledge and surveys and found that the structure and associated building materials in Technical Area 16 Building 380 (TA-16-380) are candidates for unrestricted use and public release. This finding is consistent with the requirements of DOE Order 458.1, Radiation Protection of the Public and the Environment and LANL Procedure FSD-004, Environmental Radiation Protection.
The National Nuclear Security Administration (NNSA), a semi-autonomous agency within the U.S. Department of Energy (DOE), is proposing new construction in lower Sandia Canyon at Technical Area (TA) 72 at the Guard Post 10 vehicle inspection station at Los Alamos National Laboratory (LANL). The proposed project is intended to provide expedited inspection times for vehicles transporting time sensitive loads, such as concrete and asphalt. The project activities within the 100-year floodplain include installation of 1) installation of an expedited vehicle inspection lane, 2) relocation of a 4-strand wire fence, 3) possible relocation of at least one power pole, and 4) a laydown area (Figures 1 and 2).
The Radioactive Air Emissions Management (RAEM) team performed stack flow characterization tests at Technical Area (TA) 59 Building 0001 Exhaust Stack (ES) 8. These tests were completed in accordance with Title 40 of the Code of Federal Regulations (CFR), Part 61, Subpart H and the American National Standards Institute (ANSI) N13.1-1999 required by the Clean Air Act. Subpart H of the regulation is the National Emission Standards for Hazardous Air Pollutants (NESHAP) for radionuclides, which compliance with is maintained by the REAM team.
This paper will document the air emissions source term for the TA-53 Building 0984 Isotope Production Facility (IPF). The facility has historically been managed as a minor source under Radionuclide NESHAP regulations, but began using a wider variety of irradiation targets and a higher beam current. To support expanded generation of actinium-225 for medical diagnostic and therapeutic uses, IPF is now irradiating thorium targets and the beam current is planned to increase from 250 microamperes up to 600 microamperes. These changes merit a review of the anticipated source term under the new proposed operational conditions. The end result of the review indicates the main stack (Exhaust Stack ES-1) needs to be managed as a major source with continuous emissions monitoring. No additional advance notifications or permitting is required as a result of these operational changes.
We present theories and techniques to support safe, predictable, and efficient impact testing at the Sandia National Laboratories TA-III Mechanical Shock Complex (MSC), located in Building 6570. The two testing instruments used at the MSC are the 20-inch actuator, which is a launcher that propels sleds down an indoor track, and an indoor 6-in bore compressed-gas powered cannon. The theories and techniques presented derive from basic mechanical engineering principles but are significantly informed and validated by testing experience at the MSC.
Prior research has shown that radio frequency identification (RFID) technology offers potential benefits for streamlining inventory management amidst rising production levels across the NNSA/DOE complex, yet it also presents substantial risks. RFID presents challenges never faced by LANL but also significant opportunities for accelerated inventory identification, real-time locating of assets, and minimized radiation exposure. This risk assessment evaluates the implementation of RFID technology at different Technical Area 55 (TA-55) locations, primarily withing the RLUOB basement and PF-4.
63,65 Cu angular distributions resolved for ENDF/B-VIII.1, consistent with both differential data and integral benchmark performance. 139 La RRR and URR evaluations will be merged with the LANL high energy evaluation, and to be submitted to the future ENDF-B release (post-VIII.1). 14 N RRR evaluation is planned to produce n+ 14 N, p+ 14 C, and a+ 11 B contributions to be submitted to the future ENDF-B release (post-VIII.1). 181 Ta covariances repaired and reported as intended in an errata to ENDF/B-VIII.1.
An integrated computational materials engineering (ICME) method is in development for rapid thermodynamic experimental investigation and high-fidelity computational modeling of refractory multi-principal element alloys (RMPEAs). These ultra-high-temperature (UHT) alloys are of interest for structural applications in extreme environments, but deficiency of reliable data, especially melting temperatures, impedes the prediction of alloys with favorable properties. The method leverages UHT capabilities and computational expertise of LLNL’s Materials Science Division and the McCormack Lab’s UHT conical nozzle levitation (CNL) system to iteratively map the Nb-Ta-Zr phase space, with focus on the liquidus surface, through targeted experiments selected by quantifying uncertainty in the thermodynamic model fitting parameters. This method will reduce the time to map uncharted RMPEA phase space and thereby accelerate discovery and development of advanced materials for applications in extreme environments.
A void coalescence term was proposed as an addition to the original void nucleation and growth (NAG) model to accurately describe void evolution under dynamic loading. The new model, termed as modified void nucleation and growth model (MNAG model), incorporated analytic equations to explicitly account for the evolution of the void number density and the void volume fraction (damage) during void nucleation, growth, as well as the coalescence stage. The parameters in the MNAG model were fitted to molecular dynamics (MD) shock data for single-crystal and nanocrystalline Ta, and the corresponding nucleation, growth, and coalescence rates were extracted. The results suggested that void nucleation, growth, and coalescence rates were dependent on the orientation as well as grain size. Compared to other models, such as NAG, Cocks–Ashby, Tepla, and Tonks, which were only able to reproduce early or later stage damage evolution, the MNAG model was able to reproduce all stages associated with nucleation, growth, and coalescence. The MNAG model could provide the basis for hydrodynamic simulations to improve the fidelity of the damage nucleation and evolution in 3-D microstructures.
Refractory high-entropy alloys (HEAs) are promising candidates for next-generation nuclear applications, particularly fusion reactors, due to their excellent high-temperature mechanical properties and irradiation resistance. Here, the microstructure and mechanical behavior were investigated for an equimolar WTaTiVZr HEA, designed from a palette of low-activation elements. The as-cast alloy exhibited a dendritic microstructure composed of W-Ta rich dendrites and Zr-Ti-V rich inter-dendritic regions, both possessing a body-centered cubic (BCC) crystal structure. Room temperature bulk compression tests showed ultra-high strength of around 1.6 GPa and plastic strain ~6%, with fracture surfaces showing cleavage facets. The alloy also demonstrated excellent high-temperature strength of ~650 MPa at 500 °C. Scratch-based fracture toughness was ~38 MPa√m for the as-cast WTaTiVZr HEA compared to ~25 MPa√m for commercially used pure tungsten. This higher value of fracture toughness indicates superior damage tolerance relative to commercially used pure tungsten. These results highlight the alloy’s potential as a low-activation structural material for high-temperature plasma-facing components (PFCs) in fusion reactors.
A suite of 37 molecular dynamics simulations is conducted at two system sizes to systematically characterize the role of grain boundary (GB) misorientation on spall strength in pure BCC tantalum (Ta). The systems studied consist of bicrystals with a single [110] symmetric tilt grain boundary. Two loading conditions are compared: (i) homogeneous extension under uniaxial strain simulated in this study and (ii) piston/flyer impact of sample, which induces heterogeneous deformation via shockwave propagation along the length of the sample. The piston/flyer impact is taken from the literature and run on the same set of GB misorientation angles using LAMMPS. The major finding here is that both methods result in similar spall strength predictions, but the homogeneous extension method generally requires two to three orders of magnitude fewer atoms and similar reductions in computational costs. Spall strength results systematically overpredict using this method, by about 10% for the dataset three orders of magnitude smaller than piston/flyer simulations, and 5% for the dataset two orders of magnitude smaller. Lastly, the effect of system size and pre-compression magnitude on spall strength is systematically characterized.
Waste is a Product. It must be manufactured in complete compliance with the customers’ (WIPP, various LLW sites) specification. Programmatic, facility, and maintenance personnel originate the waste. NPI-6 is the waste generator (key legal term). Our customers are the waste originators.
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