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At least 559 records · Page 31

Operational Planning Strategy for a Sequim Bay Underwater UXO Test Site (SBU2)

The Department of Defense (DoD) has identified more than 400 underwater sites that are potentially contaminated with munitions. Most areas are in shallow water (0-35 m) where the munitions pose a threat to human health and the environment. The Strategic Environmental Research and Development Program (SERDP) and Environmental Security Technology Certification Program (ESTCP) held a workshop in 2018 to establish the requirements, framework, protocols, responsibilities, and time lines for development of a series of underwater UXO Standardized Demonstration sites (“test beds”) for the purpose of testing the efficacy of sensors, equipment, and technologies to detect UXO. The workshop recommended a phased approach to building test beds to capitalize on: 1) incorporation of lessons learned from existing DoD funded projects, 2) leveraging existing underwater test bed environments funded by other programs, and 3) supporting recursive learning from early phases of the test bed development (i.e. efficiently optimizing through a scaling-up approach). This strategy document provides the framework to establish a working operational plan for the Sequim Bay Underwater UXO (SBU2) Test Bed (Phase II). Details of the plan are dependent on earlier phases of the effort as shown in Figure 1. Results from Phase I are being evaluated, and when complete, will inform the next iteration of this plan. As such, it should be considered a living document that will be informed by the lessons learned and updated as new information becomes known and requirements are refined. This approach will allow SBU2 to evolve to meet the needs of the remediation community.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

Laboratory biological safety cabinet (BSC) explosion

Scientists at universities across Iraq are actively working to report actual incidents and accidents occurring in their laboratories in order to raise awareness and encourage openness, leading to widespread adoption of robust Chemical Safety and Security (CSS) practices. This manuscript is the first in a series of five case studies describing laboratory incidents and accidents in Iraqi university laboratories in order to share lessons learned and minimize the possibility of similar incidents in the future. In this study, we describe a serious event that resulted in a postgraduate student sustaining serious injuries when the biological safety cabinet (BSC) she was using exploded. Of particular note, the paper highlights how a combination of failures and deficiencies at many levels within an organization and its technical community (rather than a single piece of faulty equipment or the careless behavior of one person) can lead to a dangerous, potentially life-threatening incident. By openly sharing what happened along with the lessons learned from the accident, we hope to minimize the possibility of another researcher being injured in a similar incident in the future.

biological safety cabinet↗

UAS IMPLEMENTATION CONSIDERATIONS FOR NUCLEAR SECURITY

Uncrewed aerial systems (UAS) have been an area of focus for the Office of International Nuclear Security within the US Department of Energy’s National Nuclear Security Administration and other foreign and domestic organizations for several years. This emerging technology provides significant capabilities to the nuclear security realm, but there are many things to consider when implementing them into an established security design or network. The goal of this paper is to discuss some of the benefits, challenges, and lessons learned with using UAS at nuclear facilities and during transport of material. Generic examples of UAS implementation will be used to facilitate a publicly releasable paper and presentation. The paper will start with a summary of the types and capabilities of UAS to provide a better understanding for people unfamiliar with current and new capabilities of these systems. Since there are many different types and sizes of UAS, this paper will focus on drones 55 lb and smaller. Then some of the use cases of UAS for security and challenges of employing them will be covered. Finally, lessons learned and some best practices that Oak Ridge National Laboratory has discovered from research, development, testing, and evaluation will be summarized.

Stockwell, Brandon↗

Added value for integrated marine energy data systems

Launched in 2019, the Portal and Repository for Information on Marine Renewable Energy (PRIMRE) provides centralized access, standardization, community building, and integration of United States (U.S.) databases, tools and codes, and other resources that cover a range of marine energy information. The PRIMRE universe contains a series of Knowledge Hubs that represent data and information on testing of marine energy devices (MHKDR); environmental effects (Tethys); engineering and technical papers (Tethys Engineering); descriptions of marine energy companies and technologies (Marine Energy Projects Database); codes and models (Marine Energy Software); and guidance on testing and measurements (Telesto). Content is added to PRIMRE by applying a set of Guidelines and Best Practices (PRIMRE Guidelines). An aggregate search across the PRIMRE site enables users to find data and information from all the PRIMRE Knowledge Hubs simultaneously, using a single entry-point (PRIMRE Search). In addition to providing access to a range of data and information on marine energy development, testing, and effects, PRIMRE allows for the development of value added products and processes that will help move the marine energy industry forward. The PRIMRE team has recently launched two key initiatives in the U.S.—Signature Projects and Lessons Learned. Outputs and outcomes from these two initiatives will be highlighted in this paper. The Signature Projects initiative is intended to bring focus to a selection of ongoing and completed marine energy projects funded by the U.S. Department of Energy’s Water Power Technologies Office (WPTO), and to inform the marine energy community of what investigations have been undertaken, what tools are available, and where gaps in information persist. Each Signature Project tags papers, reports, and data from large marine energy research projects, providing easy access and attention to all the output and associated products from each project. The Lessons Learned initiative is intended to ensure that hard-won achievements are recognized and available for those who come later, that missteps and unfortunate outcomes can be prevented in future, and that efficiencies and effective shortcuts can be publicized and used as the marine energy industry moves forward. This initiative builds off the Knowledge Hubs and reaches out to members of the marine energy community, particularly technology developers and researchers, to integrate experience in the development, deployment, assessment, success, and challenges while creating this new industry and field of study.

Copping, Andrea E.↗

Added value for integrated marine energy data systems

Launched in 2019, the Portal and Repository for Information on Marine Renewable Energy (PRIMRE) provides centralized access, standardization, community building, and integration of United States (U.S.) databases, tools and codes, and other resources that cover a range of marine energy information. The PRIMRE universe contains a series of Knowledge Hubs that represent data and information on testing of marine energy devices (MHKDR); environmental effects (Tethys); engineering and technical papers (Tethys Engineering); descriptions of marine energy companies and technologies (Marine Energy Projects Database); codes and models (Marine Energy Software); and guidance on testing and measurements (Telesto). Content is added to PRIMRE by applying a set of Guidelines and Best Practices (PRIMRE Guidelines). An aggregate search across the PRIMRE site enables users to find data and information from all the PRIMRE Knowledge Hubs simultaneously, using a single entry-point (PRIMRE Search). In addition to providing access to a range of data and information on marine energy development, testing, and effects, PRIMRE allows for the development of value added products and processes that will help move the marine energy industry forward. The PRIMRE team has recently launched two key initiatives in the U.S.—Signature Projects and Lessons Learned. Outputs and outcomes from these two initiatives will be highlighted in this paper. The Signature Projects initiative is intended to bring focus to a selection of ongoing and completed marine energy projects funded by the U.S. Department of Energy’s Water Power Technologies Office (WPTO), and to inform the marine energy community of what investigations have been undertaken, what tools are available, and where gaps in information persist. Each Signature Project tags papers, reports, and data from large marine energy research projects, providing easy access and attention to all the output and associated products from each project. The Lessons Learned initiative is intended to ensure that hard-won achievements are recognized and available for those who come later, that missteps and unfortunate outcomes can be prevented in future, and that efficiencies and effective shortcuts can be publicized and used as the marine energy industry moves forward. This initiative builds off the Knowledge Hubs and reaches out to members of the marine energy community, particularly technology developers and researchers, to integrate experience in the development, deployment, assessment, success, and challenges while creating this new industry and field of study.

Copping, Andrea E.↗

Added Value for Integrated Marine Energy Data Systems (February 2021)

Launched in 2019, the Portal and Repository for Information on Marine Renewable Energy (PRIMRE) provides centralized access, standardization, community building, and integration of United States (U.S.) databases, tools and codes, and other resources that cover a range of marine energy information. The PRIMRE universe contains a series of Knowledge Hubs that represent data and information on testing of marine energy devices (MHKDR); environmental effects (Tethys); engineering and technical papers (Tethys Engineering); descriptions of marine energy companies and technologies (Marine Energy Projects Database); codes and models (Marine Energy Software); and guidance on testing and measurements (Telesto). Content is added to PRIMRE by applying a set of Guidelines and Best Practices (PRIMRE Guidelines). An aggregate search across the PRIMRE site enables users to find data and information from all the PRIMRE Knowledge Hubs simultaneously, using a single entry-point (PRIMRE Search). In addition to providing access to a range of data and information on marine energy development, testing, and effects, PRIMRE allows for the development of valueadded products and processes that will help move the marine energy industry forward. The PRIMRE team has recently launched two key initiatives in the U.S.-Signature Projects and Lessons Learned. Outputs and outcomes from these two initiatives will be highlighted in this paper. The Signature Projects initiative is intended to bring focus to a selection of ongoing and completed marine energy projects funded by the U.S. Department of Energy's Water Power Technologies Office (WPTO), and to inform the marine energy community of what investigations have been undertaken, what tools are available, and where gaps in information persist. Each Signature Project tags papers, reports, and data from large marine energy research projects, providing easy access and attention to all the output and associated products from each project. The Lessons Learned initiative is intended to ensure that hard-won achievements are recognized and available for those who come later, that missteps and unfortunate outcomes can be prevented in future, and that efficiencies and effective shortcuts can be publicized and used as the marine energy industry moves forward. This initiative builds off the Knowledge Hubs and reaches out to members of the marine energy community, particularly technology developers and researchers, to integrate experience in the development, deployment, assessment, success, challenges while creating this new industry and field of study.

data sharing↗

Approach to Quality Assurance for Complex Environmental Modeling - 20407

A strong Quality Assurance (QA) program for complex environmental modeling is essential for regulatory and public acceptance and trust, but it does not have to be onerous. Neptune and Company, Inc. (Neptune) has developed a strong QA program that improves transparency, traceability, reproducibility, and therefore, defensibility and trust. Neptune's QA program has evolved over the past 27 years, transitioning from an ad hoc QA program, to a program that is currently Nuclear Quality Assurance-1 (NQA-1) compliant, and will soon be NQA-1/DOE approved for DOE EM modeling work. In addition, Neptune is a qualified laboratory assessor and qualified auditor for reference materials, a proficiency testing provider, and fully complies with the Environmental Protection Agency (EPA) QA program. Neptune's President and CEO, Kelly Black, was recently named the Chairperson of the International Organization for Standardization (ISO) Technical Committee 69, Application of Statistical Methods. A strong QA program has been developed for Neptune's radiological performance assessment (PA) program. Although pieces of their QA program are currently in development, their current program includes document control using Subversion, issue tracking and work flow tracking using JIRA, and transparency and traceability via a system of 'calc sheets' for documentation of all data analysis and modeling combined with 'check print' documentation of QA checking, and rigorous model testing and configuration control. All work is reviewed by an independent subject matter expert who is not associated with the collection and assembly of information, for an internal peer review. The program is enforced with a handful of Standard Operation Procedures (SOPs), Work Instructions, QA Project Plans (QAPPs), and Quality Management Plans (QMPs) that are updated frequently, with required annual training and acknowledgment. In addition, effective communication of modeling approaches and results to clients and stakeholders are integral to their QA program. Many of their models are built using the GoldSim modeling platform, for which their models are well-known for their level of transparency, documentation, and QA traceability. This level of QA is also applied to their process-level models. Neptune has taken some lessons learned from the extremely rigorous QA program required for the Yucca Mountain Project (YMP), and imposed the YMP requirements of complete traceability, transparency, and reproducibility, but avoided the inflexibility of a QA program that likely contributed to the suspect e-mails in 2005 that resulted in loss of trust in the YMP, and in nuclear waste disposal (and nuclear power) in general. There are far too many examples of loss of public trust due to poor QA that could have been easily avoided with a simple and straight-forward QA program combined with stakeholder engagement. The purpose of this paper is to share features of Neptune's Radiological Performance Assessment program QA program, and some of their QA related lessons learned over the past 27 years of QA for complex environmental modeling. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Technology Basis for Savannah River Tank Closure Cesium Removal Project - 17448

Westinghouse is currently executing a contract, awarded in June 2016 from Savannah River Remediation LLC, to deliver a system capable of removing solids and up to 100,000 curies of Cesium-137 from tank 10H, located in the Savannah River 'tank farm'. Savannah River Remediation currently has the responsibility to perform work for the Savannah River Site Liquid Waste Operations Program at the Savannah River Site for the US government, represented by the US DOE under their Principal contract. The scope of work covers the detailed design, procurement, fabrication, and delivery of the system to the Savannah River Site. It also includes the factory acceptance testing of the system, prior to delivery to site. Before leaving the site, Westinghouse will perform an evaluation of the system assembly and operations training for the incumbent operator. The basis for the technology chosen to accomplish the solids and Cesium-137 removal is unique to the specific feed stream, but is based on well-known and successful technology, Toshiba SARRY water cleanup system. Toshiba is Westinghouse's parent company, allowing us to reach back and incorporate the lessons learned during the water cleanup at Fukushima Daiichi and the integration of various technologies. Another key to the technology basis was the ion exchange media selection. A number of possible ion exchange media for the cesium removal were considered with the final choice being inorganic CST resin. Several criteria were considered and compared, such as the radiation sensitivity of the CST and the cesium specific ion preference. This paper will present the conceptual design of the modular system, noting the key benefits of specific components in the overall technology basis. Along with the design, a look at key technology improvements carried into the design through the Toshiba SARRY system will be incorporated. A first feedback on the implementation of the overall project will be provided. Since this system is a first-of-a-kind in this specific application, interesting lessons learned will be provided for future tank closure activities. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Collaboratory=Collaborate+Laboratory: The Mid-Columbia STEM Education Collaboratory

Pacific Northwest National Laboratory created a network focused on collaboration in STEM education to design and deliver projects, resources, and professional learning opportunities in a testbed environment. How do you uncover and fill gaps in equitable access to high-quality science, technology, engineering, and math (STEM) education offerings in your local region? Where might you deploy strategies to improve STEM workforce preparation and increase public understanding of STEM-oriented issues? And how can you help to ensure that students, educators, parents, and the community are aware of these programs and know how to access them in schools, colleges, and community venues? If you are the Pacific Northwest National Laboratory (PNNL), you take on the huge goal of designing and implementing an innovative STEM education collaboration project that impacts all levels of local education, both inside and outside of school settings. PNNL is one of the 17 national laboratories funded by the U.S. Department of Energy. Operated by Battelle, PNNL has a vested interest in preparing the next generation of scientists and engineers for their future careers, thus building a STEM-capable workforce and creating a STEM-literate community. One of Battelle’s core principles is a commitment to STEM education and its role in business competitiveness and quality of life. PNNL has been active in STEM education for decades, providing internships for future scientists, giving educators in-house lab experiences, and engaging its researchers in STEM outreach activities in classrooms and the community. The Collaboratory is a relatively recent outcome of Battelle’s longstanding efforts in STEM education. The original Collaboratory planning documents, developed by PNNL’s Office of STEM Education (OSE), state the objective to “design, implement, and mature a local STEM education collaboration zone that highlights the power of PNNL and Battelle to impact the educational ecosystem and serve as a model for amplifying and accelerating progress in addressing our STEM education and workforce challenges” (PNNL 2013). In other words, we (the OSE) sought to create a zone of collaboration in which members co-design and deliver STEM education programs, share findings and lessons learned from their experiences, and co-manage and sustain the organization. We started by identifying possible collaborators located nearby in the largely rural southeast corner of Washington State. Recognizing that our potential collaborators had differing norms, values, and relationships within the community, as well as their own areas of expertise and purpose, we convened representatives from K–12 public and private schools, higher education, community-based learning providers, and local business and industry to brainstorm a unified vision to resolve gaps in local STEM education needs. Through discussions with these collaborators, we started hunting for gaps where STEM efforts were lacking but a desire to improve existed. We gave ourselves permission to try things out and built a testbed space where we could experiment with new ideas, gather evidence of feasibility, and treat failures as constructive learning opportunities. Through this generative process and with seed funding from Battelle, inter-organizational teams now work together, both virtually and in real time, to develop, test, and deploy resources to support student success, educators’ effectiveness, and community engagement in STEM. Thus, the Mid-Columbia STEM Education Collaboratory (Collaboratory) was born. This is the story of our beginnings: our challenges, our lessons learned, and emerging indicators of success. For those interested in launching an education–business–community STEM learning ecosystem, we share our story.

Collaboratory↗

Preliminary Study on Recycling and Reuse of Metals from Decommissioning in Construction of Disposal Vaults in Slovakia - 17217

The decommissioning of nuclear installations represents a complex process resulting in the generation of large amounts of various waste materials. Majority of them are non-contaminated, however some of them may be hazardous as well (e.g. chemicals, asbestos, oil products, etc.). During decommissioning of NPP, significant quantities of materials with various levels of radionuclides concentration arise as well. All of these materials should be managed appropriately keeping in mind safety principles, legislative requirements, lessons learned and other relevant factors. Therefore, selection of an appropriate strategy for management of the materials arising from decommissioning is crucial and strongly influences the overall effectiveness of decommissioning process. In line with international incentives for optimization of radioactive material management, concepts of recycling and reuse of slightly radioactive materials are widely discussed and applications of these concepts are analyzed. Therefore, the paper is devoted to the preliminary study of potential for recycling of re-melted metals from decommissioning in form of reinforcement bars or mesh used in the construction of ferro-concrete disposal vaults within the near surface repository. The paper presents the preliminary results and discusses the technical and non-technical aspects related to the recycling scenario. Moreover, comparison of various scenarios related to the scrap metal clearance and recycling within nuclear industry is included. Key findings and lessons learned from study may be useful for the international community dealing with waste management optimization and in particular with recycling of materials within nuclear industry. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Updating the Dry Transfer System - 18110

The Dry Transfer System (DTS) was examined for its ability to be redesigned in order to meet needs associated with repackaging used/spent nuclear fuel (UNF/SNF) from existing storage cask systems into alternative systems, while also incorporating design advances based on some lessons learned from Orano's dry UNF handling facility (T0) located at the La Hague recycling plant. In this redesign, the DTS is envisioned to provide some flexibility through the ability to perform repackaging activities from multiple differently designed cask systems, including those with canisters that will require cutting and welding activities, and potentially with waste packages designed for disposal. The redesigned DTS is also intended to provide some operational flexibility by providing lag storage and include a means for examining UNF/SNF during repackaging, using some features implemented at the T0 facility at La Hague. This paper provides a summary of: the original DTS design, which was evaluated by the NRC and portions of which were cold-tested at Idaho National Lab; the lag storage system designed for the DTS, which is able to flexibly handle different fuel assembly designs while providing structural support for design basis events (e.g., seismic); the incorporation of lessons learned from the La Hague T0 facility into the DTS design to facilitate dry handling of UNF/SNF; and identification of other challenges towards designing a complete system. A revised DTS is envisioned to provide an important tool for the future management of UNF/SNF in preparation for transportation, re-storage, re-transportation, and/or disposal and also provides a means for repackaging UNF/SNF in case recovery from a cask/canister system is necessary (e.g., due to extended storage or a transportation event). (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Improvements to the Modeling of the TREAT Reactor and Experiments

This paper summarizes the latest improvements and lessons learned from the modeling and simulation of the transient test reactor at Idaho National Laboratory using the MAM- MOTH reactor physics application. MAMMOTH is a MOOSE-based, Finite Element Method application that specializes in the analysis of the spatial dynamics behavior of nuclear reactors. Since early 2018 several transient tests have been conducted at TREAT, thus providing the opportunity to apply and benchmark modern modeling and simulation tools. MAMMOTH was used to provide predictions of the power coupling factor between the core and the experiment for various experiments. Even though the power coupling factor predictions agree very well with the experimental data, within the bounds of the experimental uncertainty, one shortcoming was the underprediction of the total energy deposited in the core and in the experiment. Determination of the sources for this discrepancy are ongoing, but several key problems have been identified and resolved, thus providing valuable insights for future research. This paper discusses several of these lessons learned. First, the heat capacity data for the TREAT fuel has some significant problems due to limitations of the measurement techniques used circa 1960s. The sensitivity of the peak power and the total energy deposition to various representations of the heat capacity is approximately 5%. Second, the effects of the biological shield and thermal column on the modeling of the core are non-negligible, since they affect the mean generation time and the effective reflection of neutrons back into the core, which is suspected to be important during the core heat up. Matching the reactor period resolves the fact that the reduced spatial domain used in the MAMMOTH model underpredicts the mean generation time. The neutron reflection from these regions is marginally improved with the use of an albedo boundary condition. Third, modeling of the control rod movement with a multi-scheme method is introduced and its current limitations are exposed. Fourth, we explore the effects of using a homogenized model with Superhomogenization equivalence and how that differs from fully heterogeneous simulations. Finally, the energy condensation effects for this graphite core are significant. Solutions with 10 and 26 energy groups show the benefits of using a finer coarse group structure.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

URS/WTP's Future Leader Program and AECOM's Early Career Professional Technology Exchange - 17239

URS Energy and Construction, Inc. (URS), a subsidiary of AECOM, is the Bechtel National, Inc. (BNI) teaming subcontractor on the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Project. Recently, the WTP Project has begun a transition toward facility turnover and commissioning. With that transition came the hiring of staff for the startup and commissioning workforce. With many of these individuals being Early Career Professionals (ECPs), URS recognized a need to create and implement a workforce development program to give these professionals the skills to thrive in a professional environment and provide a sense of community to improve talent retention. The result of this recognition of need was the creation of URS/WTP Future Leaders. This paper will share the successes and lessons learned related to founding the URS/WTP Future Leaders. This includes establishing programs such as the Continuous Learning Workshops, Rotational Program, and implementing a mentor program. In addition, establishing a budget and obtaining support from Human Resources will be discussed. By March 2017, the ECP program will have been in effect for approximately two years. As a separate effort, many of AECOM's major waste remediation contractors have started having Early Career Professional Technology Exchanges (ECP TE) in an effort to create collaboration between sites and to establish industry contacts that will continue to be a resource for years to come. Washington River Protection Solutions, LLC; URS/WTP; Savannah River Remediation, LLC; and Nuclear Waste Partnership, LLC have conducted ECP TE, with each site hosting an event. For these events, each participant prepares a presentation and answers questions on the presentation topic. This allows ECPs to practice presentation skills, develop skills in answering questions from their peers and management, and be the expert in the room on a particular topic. Tours of the onsite facilities also are given as a way for ECPs to gain a broader understanding of the waste remediation industry and the challenges that other sites are facing. Accomplishments, lessons learned, and future plans for ECP TE will be discussed. The ECP TE events allow AECOM, as the parent company, to provide a unique learning opportunity to the next generation of engineers within the DOE nuclear field and to ensure the safe operations of these nuclear sites for years to come. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Lithium-ion battery physics and statistics-based state of health model

A pseudo-2d model using COMSOL Multiphysics® software is developed to simulate performance and performance degradation of Li-ion batteries consisting of layered and olivine cathodes with graphite anode when subjected to peak shaving grid service. Multiple degradation pathways are considered, including solid electrolyte interphase (SEI) formation and breakdown at the anode, cathode dissolution and its synergistic effect on SEI formation at the anode. The model is validated by simulating commercial cylindrical cell performance. A global model is developed to simulate performance across all chemistries, along with individual chemistry models using global model parameters as initial values. There is good agreement between these models for various optimization parameters such as SEI equilibrium potential, cathode dissolution exchange current density, solvent diffusivity in the SEI and SEI ionic conductivity. To circumvent time constraints related to the COMSOL model, a 0d global model is developed which fits data well and provides more clarity on differences in cathode dissolution exchange current density. Again, good agreement for various optimization parameters is obtained among the COMSOL global & individual chemistry models and the 0-d model. The lessons learned from the physics-based model is used to develop a top down statistics-based model using current, voltage and anode volumetric change per mole lithium intercalated, along with their interactions as degradation predictors. This model predicts out of sample degradation for multiple grid services and electric vehicle drive cycle with high accuracy and provides the pathway to develop an efficient battery management system combining machine learning and findings from physics-based computationally intensive algorithms.

Crawford, Aladsair J.↗

High-resolution Hindcasts for U.S. Wave Energy Resource Characterization

The marine and hydrokinetic (MHK) industry is at an early stage of development and has the potential to play a significant role in diversifying the U.S. energy portfolio and reducing the U.S. carbon footprint. Wave energy is the largest among all the U.S. MHK energy resources, which include wave energy, ocean current, tidal-instream, ocean thermal energy conversion, and river-instream. Wave resource characterization is an essential step for regional wave energy assessments, Wave Energy Converter (WEC) project development, site selection and WEC design. The present paper provides an overview of a joint modelling effort by the Pacific Northwest National Laboratory and Sandia National Laboratories on high-resolution wave hindcasts to support the U.S. Department of Energy’s Water Power Technologies Office’s program of wave resource characterization, assessment and classifications in all US coastal regions. Topics covered include the modelling approach, model input requirements, model validation strategies, high performance computing resource requirements, model outputs and data management strategies. Examples of model setup and validation for different regions are provided along with application to development of classification systems, and analysis of regional wave climates. Lessons learned and technical challenges of the long-term, high-resolution regional wave hindcast are discussed.

Yang, Zhaoqing↗

Performance of the Gemini Planet Imager Non-redundant Mask and Spectroscopy of Two Close-separation Binaries: HR 2690 and HD 142527

The Gemini Planet Imager (GPI) contains a 10-hole non-redundant mask (NRM), enabling interferometric resolution in complement to its coronagraphic capabilities. The NRM operates both in spectroscopic (integral field spectrograph, henceforth IFS) and polarimetric configurations. NRM observations were taken between 2013 and 2016 to characterize its performance. Most observations were taken in spectroscopic mode, with the goal of obtaining precise astrometry and spectroscopy of faint companions to bright stars. We find a clear correlation between residual wavefront error measured by the adaptive optic system and the contrast sensitivity by comparing phase errors in observations of the same source, taken on different dates. We find a typical 5σ contrast sensitivity of (2–3) × 10 –3 at $~λ/D$. We explore the accuracy of spectral extraction of secondary components of binary systems by recovering the signal from a simulated source injected into several data sets. We outline data reduction procedures unique to GPI's IFS and describe a newly public data pipeline used for the presented analyses. We demonstrate recovery of astrometry and spectroscopy of two known companions to HR 2690 and HD 142527. NRM+polarimetry observations achieve differential visibility precision of σ ~ 0.4% in the best case. We discuss its limitations on Gemini-S/GPI for resolving inner regions of protoplanetary disks and prospects for future upgrades. We summarize lessons learned in observing with NRM in spectroscopic and polarimetric modes.

79 ASTRONOMY AND ASTROPHYSICS↗

Design of the polar neutron-imaging aperture for use at the National Ignition Facility

The installation of a neutron imaging diagnostic with a polar view at the National Ignition Facility (NIF) required design of a new aperture, an extended pinhole array (PHA). This PHA is different from the pinhole array for the existing equatorial system due to significant changes in the alignment and recording systems. The complex set of component requirements, as well as significant space constraints in its intended location, makes the design of this aperture challenging. In addition, lessons learned from development of prior apertures mandate careful aperture metrology prior to first use. This paper discusses the PHA requirements, constraints, and the final design. The PHA design is complex due to size constraints, machining precision, assembly tolerances, and design requirements. When fully assembled, the aperture is a 15 mm × 15 mm × 200 mm tungsten and gold assembly. The PHA body is made from 2 layers of tungsten and 11 layers of gold. The gold layers include 4 layers containing penumbral openings, 4 layers containing pinholes and 3 spacer layers. In total, there are 64 individual, triangular pinholes with a field of view (FOV) of 200 μm and 6 penumbral apertures. Each pinhole is pointed to a slightly different location in the target plane, making the effective FOV of this PHA a 700 μm square in the target plane. The large FOV of the PHA reduces the alignment requirements both for the PHA and the target, allowing for alignment with a laser tracking system at NIF.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗