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PNNL-Richland Campus Radionuclide Air Emissions Report for Calendar Year 2023

This report documents radionuclide air emissions that result in the 2023 highest effective dose equivalent (EDE) to an offsite member of the public, referred to as the maximally exposed individual (MEI). The report has been prepared in compliance with the Code of Federal Regulations, Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants, Subpart H, “National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities” and Washington Administrative Code Chapter 246-247, “Radiation Protection–Air Emissions.” The dose to the PNNL-Richland campus MEI from routine emissions sources, excluding radon, in 2023 from campus sources is 2.0E-5 mrem (2.0E-7 mSv) EDE. The dose from radon emissions is 4.0E-7 mrem (4.0E-09 mSv) EDE. No nonroutine emissions occurred in 2023. The total radiological dose to the MEI from all PNNL-Richland campus radionuclide emissions, including fugitive emissions and radon, is 2.1E-5 mrem (2.1E-7 mSv) EDE, or more than 100,000 times less than the federal and state standard of 10 mrem/yr, with which the PNNL-Richland campus is in compliance.

40 CFR 61 Subpart H↗

PNNL Richland Campus Radionuclide Air Emissions Report for Calendar Year 2017

This report documents radionuclide air emissions that result in the 2017 highest effective dose equivalent (EDE) to an offsite member of the public, referred to as the maximally exposed individual (MEI). The report has been prepared in compliance with the Code of Federal Regulations, Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants, Subpart H, “National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities” and Washington Administrative Code Chapter 246-247, “Radiation Protection–Air Emissions.” The dose to the PNNL Richland Campus MEI from routine major and minor point source emissions in 2017 from PNNL Richland Campus sources is 2.1E-5 mrem (2.1E-7 mSv) EDE. The dose from all fugitive sources is 2.1E-6 mrem (2.1E-8 mSv) EDE. The dose from radon emissions is 3.9E-10 mrem (3.9E-12 mSv) EDE. No nonroutine emissions occurred in 2017. The total radiological dose to the MEI from all PNNL Richland Campus radionuclide emissions, including fugitive emissions and radon, is 2.3E-5 mrem (2.3E-7 mSv) EDE, or more than 10,000 times less than the federal and state standard of 10 mrem/yr, with which the PNNL Richland Campus is in compliance.

40 CFR 61 Subpart H↗

PNNL Richland Campus Radionuclide Air Emissions Report for Calendar Year 2018

This report documents radionuclide air emissions that result in the 2018 highest effective dose equivalent (EDE) to an offsite member of the public, referred to as the maximally exposed individual (MEI). The report has been prepared in compliance with the Code of Federal Regulations, Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants, Subpart H, “National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities” and Washington Administrative Code Chapter 246-247, “Radiation Protection–Air Emissions.” The dose to the PNNL Richland Campus MEI from routine major and minor point source emissions in 2018 from PNNL Richland Campus sources is 1.6E-5 mrem (1.6E-7 mSv) EDE. The dose from all fugitive sources is 2.1E-6 mrem (2.1E-8 mSv) EDE. The dose from radon emissions is 5.6E-10 mrem (5.6E-12 mSv) EDE. No nonroutine emissions occurred in 2018. The total radiological dose to the MEI from all PNNL Richland Campus radionuclide emissions, including fugitive emissions and radon, is 1.8E-5 mrem (1.8E-7 mSv) EDE, or more than 10,000 times less than the federal and state standard of 10 mrem/yr, with which the PNNL Richland Campus is in compliance.

40 CFR 61 Subpart H↗

PNNL Richland Campus Radionuclide Air Emissions Report for Calendar Year 2019

This report documents radionuclide air emissions that result in the 2019 highest effective dose equivalent (EDE) to an offsite member of the public, referred to as the maximally exposed individual (MEI). The report has been prepared in compliance with the Code of Federal Regulations, Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants, Subpart H, “National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities” and Washington Administrative Code Chapter 246-247, “Radiation Protection–Air Emissions.” The dose to the PNNL Richland Campus MEI from routine major and minor point source emissions in 2019 from PNNL Richland Campus sources is 1.4E-5 mrem (1.4E-7 mSv) EDE. The dose from all fugitive sources is 1.3E-6 mrem (1.3E-8 mSv) EDE. The dose from radon emissions is 1.5E-10 mrem (1.5E-12 mSv) EDE. No nonroutine emissions occurred in 2019. The total radiological dose to the MEI from all PNNL Richland Campus radionuclide emissions, including fugitive emissions and radon, is 1.5E-5 mrem (1.5E-7 mSv) EDE, or more than 10,000 times less than the federal and state standard of 10 mrem/yr, with which the PNNL Richland Campus is in compliance.

40 CFR 61 Subpart H↗

PNNL Richland Campus Radionuclide Air Emissions Report for Calendar Year 2020

This report documents radionuclide air emissions that result in the 2020 highest effective dose equivalent (EDE) to an offsite member of the public, referred to as the maximally exposed individual (MEI). The report has been prepared in compliance with the Code of Federal Regulations, Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants, Subpart H, “National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities” and Washington Administrative Code Chapter 246-247, “Radiation Protection–Air Emissions.” The dose to the PNNL Richland Campus MEI from routine major and minor point source emissions in 2020 from PNNL Richland Campus sources is 1.5E-5 mrem (1.5E-7 mSv) EDE. The dose from all fugitive sources is 2.0E-6 mrem (2.0E-8 mSv) EDE. The dose from radon emissions is 9.3E-9 mrem (9.3E-11 mSv) EDE. No nonroutine emissions occurred in 2020. The total radiological dose to the MEI from all PNNL Richland Campus radionuclide emissions, including fugitive emissions and radon, is 1.7E-5 mrem (1.7E-7 mSv) EDE, or more than 100,000 times less than the federal and state standard of 10 mrem/yr, with which the PNNL Richland Campus is in compliance.

40 CFR 61 Subpart H↗

PNNL Richland Campus Radionuclide Air Emissions Report for Calendar Year 2021

This report documents radionuclide air emissions that result in the 2021 highest effective dose equivalent (EDE) to an offsite member of the public, referred to as the maximally exposed individual (MEI). The report has been prepared in compliance with the Code of Federal Regulations, Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants, Subpart H, “National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities” and Washington Administrative Code Chapter 246-247, “Radiation Protection–Air Emissions.” The dose to the PNNL Richland Campus MEI from routine major and minor point source emissions in 2021 from PNNL Richland Campus sources is 1.7E-5 mrem (1.7E-7 mSv) EDE. The dose from all fugitive sources is 1.2E-6 mrem (1.2E-8 mSv) EDE. The dose from radon emissions is 2.1E-9 mrem (2.1E-11 mSv) EDE. No nonroutine emissions occurred in 2021. The total radiological dose to the MEI from all PNNL Richland Campus radionuclide emissions, including fugitive emissions and radon, is 1.8E-5 mrem (1.8E-7 mSv) EDE, or more than 100,000 times less than the federal and state standard of 10 mrem/yr, with which the PNNL Richland Campus is in compliance.

40 CFR 61 Subpart H↗

PNNL-Richland Campus Radionuclide Air Emissions Report for Calendar Year 2022

This report documents radionuclide air emissions that result in the 2022 highest effective dose equivalent (EDE) to an offsite member of the public, referred to as the maximally exposed individual (MEI). The report has been prepared in compliance with the Code of Federal Regulations, Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants, Subpart H, “National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities” and Washington Administrative Code Chapter 246-247, “Radiation Protection–Air Emissions.” The dose to the PNNL Richland Campus MEI from routine major and minor point source emissions in 2022 from PNNL Richland Campus sources is 2.1E-5 mrem (2.1E-7 mSv) EDE. The dose from all fugitive sources is 1.2E-6 mrem (1.2E-8 mSv) EDE. The dose from radon emissions is 9.2E-9 mrem (9.2E-11 mSv) EDE. No nonroutine emissions occurred in 2022. The total radiological dose to the MEI from all PNNL Richland Campus radionuclide emissions, including fugitive emissions and radon, is 2.3E-5 mrem (2.3E-7 mSv) EDE, or more than 100,000 times less than the federal and state standard of 10 mrem/yr, with which the PNNL Richland Campus is in compliance.

40 CFR 61 Subpart↗

Standard review plan for evaluating nuclear power reactor license termination plans

This standard review plan (SRP) guides the staff of the U.S. Nuclear Regulatory Commission (NRC) in conducting safety reviews of license termination plans (LTPs). The principal purpose of this SRP is to ensure the quality and uniformity of NRC staff reviews and to present a well-defined base from which to evaluate the requirements for terminating the license of a nuclear power plant. It is also the purpose of this SRP to make information about regulatory matters widely available, so that interested members of the public and the nuclear industry can gain a better understanding of the NRC staff's review process. Specific guidance for licensees is included in Regulatory Guide 1.179, "Standard Format and Content of License Termination Plans for Nuclear Power Reactors." Licensees may also use this SRP to assist in developing an LTP. The SRP presents the acceptance criteria for all areas of review for license termination, and identifies the matters to be reviewed, the basis for the review, and the conclusions that are sought. For example, NUREG-1757, "Consolidated Decommissioning Guidance" offers additional guidance on how to demonstrate compliance with the unrestricted release, restricted release, and alternative criteria for license termination, in accordance with Title 10 of the Code of Federal Regulations (10 CFR), Part 20, "Standards for Protection against Radiation," Subpart E, "Radiological Criteria for License Termination." To avoid duplication of information, this SRP references applicable sections of NUREG-1757 for additional guidance. In addition, the NRC has issued supplemental guidance that will subsequently be consolidated into NUREG-1757 to address partial site release before LTP approval, and compliance with 10 CFR Part 20, Subpart E. It should be noted that the memorandum of understanding (MOU) between the Environmental Protection Agency and NRC may contain consultation triggers for some radionuclides that may be lower than the NUREG-1757 Vol. 2 Revision 1, Appendix H screening values.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

The SkyView Data Model: Handling Heterogeneous Data Using Dynamic Software

The SkyView Virtual Telescope allows users to query over 75 distinct datasets of astronomical imagery including more than 190 distinct surveys. These holdings are extraordinarily diverse ranging over more than 15 orders of magnitude in frequency and5 orders of magnitude in resolution. To accommodate supporting these data, SkyView has developed a simple data model for surveys. Nor surprisingly, given the diverse origins of the datasets included, some surveys do not easily fit within this model. The conventional approach to dealing with such outliers is to build a layer on top of the actual data which more faithfully adheres to the data model. With SkyView we have used a somewhat alternative approach. We allow the data model to define new behaviors in the SkyView code itself either by customizing the use of existing capabilities or pointing to new classes that have non-standard behavior. This approach is feasible since in modern computer languages the code that is run can be selected dynamically with new classes completely overriding traditional behavior. This paper describes this approach and considers how it may become more useful as our software structures become increasingly dynamically linked.

Thomas McGlynn↗

SAM Enhancements and Model Developments for Molten-Salt-Fueled Reactors

To support the development and utilization of the SAM code for molten-salt-fueled reactor (MSR) safety analysis and licensing, an effort was devoted to enhancing code capabilities and developing reference models for the MSR primary loop. A reference standard problem of a prototypical reactor design is foundational to NRC to verify the adequacy of computer codes and evaluation models for a specific reactor type. A thermo-fluid model of the Molten Salt Reactor Experiment (MSRE) has been developed. The MSRE primary loop model consists of a 2-D core region and external core components in 1-D or 0-D. Both the steady-state and a transient scenario are simulated. The porous medium model is utilized for both the molten salt fluid channels and the moderator matrix in the MSRE core. The use of the porous medium model for the MSRE core is verified with the higher-fidelity simulation results using 1-D representations of the fluid channels and 3-D modeling of core structures. To further enhance SAM multi-scale simulation capabilities for MSRs, a mass transport model is developed and implemented in SAM multi-dimension flow module for modeling of species transport such as delayed neutron precursors in MSRs.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

PETSc/TAO Users Manual (Rev. 3.19)

This manual describes the use of the Portable, Extensible Toolkit for Scientific Computation (PETSc) and the Toolkit for Advanced Optimization (TAO) for the numerical solution of partial differential equations and related problems on high-performance computers. PETSc/TAO is a suite of data structures and routines that provide the building blocks for the implementation of large-scale application codes on parallel (and serial) computers. PETSc uses the MPI standard for all distributed memory communication. PETSc/TAO includes a large suite of parallel linear solvers, nonlinear solvers, time integrators, and opti mization that may be used in application codes written in Fortran, C, C++, and Python (via petsc4py; see Getting Started). PETSc provides many of the mechanisms needed within parallel application codes, such as parallel matrix and vector assembly routines. The library is organized hierarchically, enabling users to employ the level of abstraction that is most appropriate for a particular problem. By using techniques of object-oriented programming, PETSc provides enormous flexibility for users. PETSc is a sophisticated set of software tools; as such, for some users it initially has a much steeper learning curve than packages such as MATLAB or a simple subroutine library. In particular, for individuals without some computer science background, experience programming in C, C++, python, or Fortran and experience using a debugger such as gdb or lldb, it may require a significant amount of time to take full advantage of the features that enable efficient software use. However, the power of the PETSc design and the algorithms it incorporates may make the efficient implementation of many application codes simpler than “rolling them” yourself. For many tasks a package such as MATLAB is often the best tool; PETSc is not intended for the classes of problems for which effective MATLAB code can be written. There are several packages, built on PETSc, that may satisfy your needs without requiring directly using PETSc. We recommend reviewing these packages functionality before starting to code directly with PETSc. PETSc can be used to provide a “MPI parallel linear solver” in an otherwise sequential, or OpenMP parallel code. This approach cannot provide extremely large improvements in the application time by utilizing large numbers of MPI processes but can still improve the performance. Certainly all parts of a previously sequential code need not be parallelized but the matrix generation portion must be parallelized to expect true scalability to large numbers of MPI processes. See PCMPI for details on how to utilize the PETSc MPI linear solver server. Since PETSc is under continued development, small changes in usage and calling sequences of routines will occur. PETSc has been supported for twenty-five years; see mailing list information on our website for information on contacting support.

97 MATHEMATICS AND COMPUTING↗

Comparing Performance of Coded Communications over Fading Channels between the Lunar South Pole & Earth

In this paper we design and analyze an end-to-endcommunication system between a lander/rover on the surface ofthe lunar South Pole and an Earth station. Various communicationsystems on the lander or rover could be used for the Earthto-Moon communication in both the uplink and downlink direction.To communicate to and from the lander/rover on the lunarSouth Pole, low and/or medium directional antennas onboardthe lander/rover will have to be pointed at low elevation anglesbetween 2 to 10 degrees, thus causing multipath fading effectsdue to reflection of a portion of the transmitted electromagneticwaves from the surface of the Moon. These are not commonlyencountered in traditional deep space communications betweena spacecraft and a ground station.We investigate various design methods and analyze such communicationsystems, in the presence of multipath fading. Wemodel the fading channel based on existing and simulated data.For coherent reception, the acquisition and tracking loop shouldacquire and track incoming carrier phase in presence of Ricianmultipath fading. For this communication system in additionto estimating the received carrier phase, the amplitude of thefading signal should also be estimated, in particular to be used inthe decoder. We consider simple modulation and coding schemesin particular those specified in the CCSDS standards for spaceapplications.After designing various components of the communication system,we use Simulink models to obtain the end-to-end performanceof the communication link under investigation. Basedon the available data, the fading channel can be accuratelymodeled as a Rician fading channel with various Rician parametersdepending on the Earth elevation angle, which alsoaffects the Doppler spread. Therefore, the challenge is todesign a communication system robust in the presence of themultipath fading where the channel conditions change in timeand thus produce fading. In summary, this paper comparespossible communication system designs, performance analysis,and simulations for coded system with/without interleaving withhard/soft decision and with/without channel state information(CSI), over a communication link between a lander/rover at theLunar south pole and a Deep Space Network station in presenceof Rician fading.

Cheung, Kar-Ming↗

Pseudospectral Maxwell solvers for an accurate modeling of Doppler harmonic generation on plasma mirrors with particle-in-cell codes

With the advent of petawatt class lasers, the very large laser intensities attainable on target should enable the production of intense high-order Doppler harmonics from relativistic laser-plasma mirror interactions. At present, the modeling of these harmonics with particle-in-cell (PIC) codes is extremely challenging as it implies an accurate description of tens to hundreds of harmonic orders on a broad range of angles. In particular, we show here that due to the numerical dispersion of waves they induce in vacuum, standard finite difference time domain (FDTD) Maxwell solvers employed in most PIC codes can induce a spurious angular deviation of harmonic beams potentially degrading simulation results. This effect was extensively studied and a simple toy model based on the Snell-Descartes law was developed that allows us to finely predict the angular deviation of harmonics depending on the spatiotemporal resolution and the Maxwell solver used in the simulations. Our model demonstrates that the mitigation of this numerical artifact with FDTD solvers mandates very high spatiotemporal resolution preventing realistic three-dimensional (3D) simulations even on the largest computers available at the time of writing. Finally, we finally show that nondispersive pseudospectral analytical time domain solvers can considerably reduce the spatiotemporal resolution required to mitigate this spurious deviation and should enable in the near future 3D accurate modeling on supercomputers in a realistic time to solution.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Investigation of fast particle redistribution induced by sawtooth instability in NSTX-U

The effects of sawtooth on fast ion transport have been examined in reproducible, 2s long sawtoothing L-mode discharges during the 2016 experimental campaign on National Spherical Torus Experiment Upgrade (NSTX-U) [J.E. Menard et al. Nucl. Fusion (2012) 083015]. Analysis of the discharges showed that standard sawtooth models (full/partial reconnection models) in the TRANSP code were not capable to fully reproduce the fast ion redistribution induced by sawtooth crashes. Some global parameters such as neutron rate can be recovered while detailed features, e.g. distribution functions, estimated using the models were different from the experimental observation. The standard sawtooth models in TRANSP do not take into account the different effect of sawtooth crashes depending on fast ion energy and orbit type and that may cause the disagreement between experiments and simulations. In this work, the newly developed kick model has been applied to replace the standard sawtooth models for the fast ion transport. TRANSP simulation results using the kick model, taking into account the characteristics of fast ion such as energy and pitch angle, can reproduce experimental neutron rates within 10\% difference. The qualitative comparison of the measurements and synthetic diagnostics of FIDA and SSNPA using the TRANSP simulation results with kick model demonstrates good agreements.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Marine Sciences Laboratory Radionuclide Air Emissions Report for Calendar Year 2013

The U.S. Department of Energy Office of Science (DOE-SC) Pacific Northwest Site Office (PNSO) has oversight and stewardship duties associated with the Pacific Northwest National Laboratory (PNNL) Marine Sciences Laboratory (MSL) located on Battelle Land – Sequim (Sequim). This report is prepared to document compliance with the Code of Federal Regulations (CFR), Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants (NESHAP), Subpart H, “National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities” and Washington Administrative Code (WAC) Chapter 246-247, “Radiation Protection–Air Emissions.” The EDE to the Sequim MEI due to routine operations in 2013 was 5E-05 mrem (5E-07 mSv). No non-routine emissions occurred in 2013. The MSL is in compliance with the federal and state 10 mrem/yr standard.

air emissions↗

Marine Sciences Laboratory Radionuclide Air Emissions Report for Calendar Year 2014

The U.S. Department of Energy Office of Science (DOE-SC) Pacific Northwest Site Office (PNSO) has oversight and stewardship duties associated with the Pacific Northwest National Laboratory (PNNL) Marine Sciences Laboratory (MSL) located on Battelle Land – Sequim.This report is prepared to document compliance with the Code of Federal Regulations (CFR), Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants (NESHAP), Subpart H, ''National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities” and Washington Administrative Code (WAC) Chapter 246-247, “Radiation Protection–Air Emissions.'' The EDE to the MSL MEI due to routine operations in 2014 was 9E-05 mrem (9E-07 mSv). No non-routine emissions occurred in 2014. The MSL is in compliance with the federal and state 10 mrem/yr standard.

54 ENVIRONMENTAL SCIENCES↗

Fidelity of the Integrated Force Method Solution

The theory of strain compatibility of the solid mechanics discipline was incomplete since St. Venant's 'strain formulation' in 1876. We have addressed the compatibility condition both in the continuum and the discrete system. This has lead to the formulation of the Integrated Force Method. A dual Integrated Force Method with displacement as the primal variable has also been formulated. A modest finite element code (IFM/Analyzers) based on the IFM theory has been developed. For a set of standard test problems the IFM results were compared with the stiffness method solutions and the MSC/Nastran code. For the problems IFM outperformed the existing methods. Superior IFM performance is attributed to simultaneous compliance of equilibrium equation and compatibility condition. MSC/Nastran organization expressed reluctance to accept the high fidelity IFM solutions. This report discusses the solutions to the examples. No inaccuracy was detected in the IFM solutions. A stiffness method code with a small programming effort can be improved to reap the many IFM benefits when implemented with the IFMD elements. Dr. Halford conducted a peer-review on the Integrated Force Method. Reviewers' response is included.

Hopkins, Dale↗

Testing of ENDF/B-VIII.0 in the GNDS format with LLNL transport codes - 25606

ENDF/B-VIII.0 was released in the Evaluated Nuclear Data Format and the Generalized Nuclear Data Structure format (GNDS), a new international standard for storing nuclear data developed under the auspices of the Nuclear Energy Agency Working Party on Evaluation Cooperation Subgroup 38. GNDS relies on modern coding practices, and offers a structured, flexible and physics-based standard for storing and exchanging nuclear data to address limitations in legacy nuclear data formats such as ENDF-6. GNDS supports the storage of evaluated nuclear data as well as processed data suitable for both deterministic (i.e., multi-group) and Monte Carlo transport codes. Lawrence Livermore National Laboratory has implemented a complete suite of codes to test GNDS data. Simulations for the ENDF/B-VIII.0 cross-section library in GNDS format are presented. Deterministic and Monte Carlo radiation transport simulations with the Ardra and Mercury codes respectively, are validated against reactivities in fast criticality safety benchmark assemblies. Finally, Mercury simulations of {sup 238}U(n,f), {sup 237}Np(n,f) and {sup 239}Pu(n,f) reaction rates in Godiva, Jezebel and Flattop are compared to MCNP results and measured data. (authors)

61 RADIATION PROTECTION AND DOSIMETRY↗