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At least 127 records · Page 7

A Pilot Study of Whole-Blood Transcriptomic Analysis to Identify Genes Associated with Repetitive Low-Level Blast Exposure in Career Breachers

Repetitive low-level blast exposure is one of the major occupational health concerns among US military service members and law enforcement. This study seeks to identify gene expression using microRNA and RNA sequencing in whole-blood samples from experienced breachers and unexposed controls. We performed experimental RNA sequencing using Illumina’s HiSeq 2500 Sequencing System, and microRNA analysis using NanoString Technology nCounter miRNA expression panel in whole-blood total RNA samples from 15 experienced breachers and 14 age-, sex-, and race-matched unexposed controls. We identified 10 significantly dysregulated genes between experienced breachers and unexposed controls, with FDR corrected <0.05: One upregulated gene, LINC00996 (long intergenic non-protein coding RNA 996); and nine downregulated genes, IGLV3-16 (immunoglobulin lambda variable 3-16), CD200 (CD200 molecule), LILRB5 (leukocyte immunoglobulin-like receptor B5), ZNF667-AS1 (ZNF667 antisense RNA 1), LMOD1 (leiomodin 1), CNTNAP2 (contactin-associated protein 2), EVPL (envoplakin), DPF3 (double PHD fingers 3), and IGHV4-34 (immunoglobulin heavy variable 4-34). The dysregulated gene expressions reported here have been associated with chronic inflammation and immune response, suggesting that these pathways may relate to the risk of lasting neurological symptoms following high exposures to blast over a career.

59 BASIC BIOLOGICAL SCIENCES↗

Special Analysis for the Disposal of the Idaho National Laboratory Idaho Chemical Processing Plant Low-Level Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

This special analysis (SA) evaluates whether the Idaho National Laboratory (INL) Idaho Chemical Processing Plant (ICPP) Low-Level waste stream is suitable for disposal by shallow land burial at the Area 5 Radioactive Waste Management Site on the Nevada National Security Site (NNSS). The INL ICPP Low-Level waste stream consists of debris and solidified liquids. The INL ICPP Low-Level waste stream requires an SA to resolve two unreviewed disposal questions (UDQs). The first UDQ addresses whether it is acceptable to dispose of radium-226 (226Ra) at an activity concentration that exceeds the NNSS Waste Acceptance Criteria (WAC) Action Level. The second UDQ evaluates the acceptability of disposing of five long-lived radionuclides without WAC action levels. Long-lived radionuclides without action levels are radionuclides not evaluated in the performance assessment.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Performance Assessment Maintenance Plan for the Active Low-Level Burial Ground Trenches 31, 34, and 94 at the Hanford Site

This report documents the maintenance plan for the Hanford Site 200 West Area Active Low-Level Burial Ground Trenches 31 and 34 and 200 East Area Active Trench 94 performance assessment (PA). The PA maintenance plan is one of several supporting documents that are compendiums to the active trenches (Trenches 31, 34, and 94) PA as required in DOE O 435.1, Radioactive Waste Management . The PA is documented in DOE/RL-2021-26, Performance Assessment of Active Trenches in 200 East and West Low-Level Burial Grounds at the Hanford Site . This plan follows the requirements and outline specified in the applicable U.S. Department of Energy (DOE) standard used for developing documents supporting DOE-STD-5002-2017, Disposal Authorization Statement and Tank Closure Documentation . This maintenance plan summarizes the following major activities DOE plans to conduct to maintain the Trenches 31, 34, and 94 PA: Monitoring; Research and development; Planned reviews and analyses; Revisions of Trenches 31, 34, and 94 PA. The planned research and development activities relate to evaluating the key assumptions, including evaluating conceptual model assumptions and parameter value assumptions used in the PA. The planned research and development activities include those that are designed to track the release mechanisms for Category 1, Category 3, and uranium billet waste sources, as well as continued characterization and related modeling of the natural environment in the Central Plateau of the Hanford Site. In addition, the planned research and development activities include focused testing and evaluation of engineered and natural materials to reduce the uncertainty in the conceptual models and parameter values used in the PA. All key and secondary issues identified during the review of the PA by the Low-Level Waste Disposal Facility Federal Review Group have been resolved prior to finalization of the PA. There are no outstanding issues.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Performance Assessment of the Active Trenches in 200 East and 200 West Low-Level Burial Grounds at the Hanford Site

The purpose of this document is to provide the assessment of the long-term human health and environmental risk associated with the continued disposal of radioactive wastes in the active trenches of the 200 East and 200 West Area Low-Level Burial Grounds (LLBGs) at the Hanford Site (Figure ES-1), as required by DOE O 435.1, Radioactive Waste Management1. Since July 1, 2004, the only active trenches in the 200 West Area LLBGs are the lined Trenches 31 and 34 used for the disposal of containerized low-level waste and mixed low-level waste (Figure ES-2). The only active trench in the 200 East Area LLBGs is the unlined Trench 94 that was used for the disposal of naval reactor compartments (Figure ES-3). Trenches 31 and 34 are intended to be used until they reach their disposal capacity while Trench 94 will be used and expanded as necessary to meet the needs of the U.S. Navy.

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The Low-Level Radioactive Waste Management Office: Thirty Years of Experience in Canada - 13308

This paper reviews thirty years of progress by the Low-Level Radioactive Waste Management Office (LLRWMO) in developing and implementing low-level radioactive waste (LLRW) remediation projects and environmentally safe co-existence strategies. It reports on the present status and the future of the national historic waste program in Canada. There are over two million cubic metres of historic LLRW in Canada. Historic LLRW is broadly defined as LLRW that was managed in the past in a manner that is no longer considered acceptable and for which the original owner cannot reasonably be held accountable. In many cases, the original owner can not be identified or no longer exists. The LLRWMO was established in 1982 as Canada's agent to carry out the responsibilities of the federal government for the management of historic LLRW. The LLRWMO is operated by Atomic Energy of Canada Limited (AECL) through a cost-recovery agreement with Natural Resources Canada (NRCan), the federal department that provides the funding and establishes national policy for radioactive waste management in Canada. The LLRWMO expertise includes project managers, environmental remediation specialists, radiation surveyors, communications staff and administrative support staff. The LLRWMO in providing all aspects of project oversight and implementation contracts additional resources supplementing core staff capacity as project/program demands require. (authors)

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Feedback oscillator functions as low-level pulse stretcher

Low trigger pulses of the pulse stretcher circuit are obtained by forward biasing the transistor oscillator. The loop gain is kept below unity and prevents free-running oscillation. Two parallel feedback loops improve the stretching capabilities.

Source record↗

Southern hemisphere low level wind circulation statistics from the Seasat scatterometer

Analyses of remotely sensed low-level wind vector data over the Southern Ocean are performed. Five-day averages and monthly means are created and the month-to-month variability during the winter (July-September) of 1978 is investigated. The remotely sensed winds are compared to the Australian Bureau of Meteorology (ABM) and the National Meteorological Center (NMC) surface analyses. In southern latitudes the remotely sensed winds are stronger than what the weather services' analyses suggest, indicating under-estimation by ABM and NMC in these regions. The evolution of the low-level jet and the major stormtracks during the season are studied and different flow regimes are identified. The large-scale variability of the meridional flow is studied with the aid of empirical orthogonal function (EOF) analysis. The dominance of quasi-stationary wave numbers 3,4, and 5 in the winter flows is evident in both the EOF analysis and the mean flow. The signature of an exceptionally strong blocking situation is evident in July and the special conditions leading to it are discussed. A very large intraseasonal variability with different flow regimes at different months is documented.

Levy, Gad↗

The Legislative and Regulatory Histories Related to Greater-Than-Class-C Low-Level Radioactive Waste - 18602

The history surrounding the legislative and regulatory developments regarding Greater-Than-Class C Low Level Radioactive Waste (GTCC LLW) is both interesting and complex. On October 25, 1978, the U.S. Nuclear Regulatory Commission (NRC) published an Advanced Notice of Proposed Rulemaking pertaining to the development of regulations for the land disposal of LLW. This regulation was one of the first undertaken by NRC since its inception pursuant to the Energy Reorganization Act of 1974. Given the problematic challenges that many States were facing with releases of radioactivity from waste disposal facilities at the time, the technical bases supporting this rulemaking were both forward-thinking and comprehensive. The rule included a waste classification system that was tiered in four waste classes: Class A, B, C and GTCC LLW. On December 27, 1982, the NRC finalized the requirements for disposing of these classes of radioactive waste in Title 10 of the Code of Federal Regulations, Part 61 (10 CFR 61). The NRC established the waste classification system to protect both members of the public and individuals that may someday inadvertently intrude in the waste placed in the disposal facility after expiration of the institutional control period. This waste classification was developed to ensure that radiation doses to members of the public and an inadvertent intruder would not exceed 0.25 mSv y{sup -1} (25 mrem y{sup -1}) or 5.0 mSv y{sup -1} (500 mrem y{sup -1}), respectively. At the time the regulation was promulgated, GTCC LLW was considered generally not suitable for near surface disposal. It was recognized that disposal of GTCC LLW would require disposal technologies having greater confinement capacity or protection than 'normal' near-surface disposal. In 1980 Congress enacted the Low-Level Waste Policy Act of 1980, as amended in 1985 (LLWPAA of 1985) that assigned responsibility of disposing of GTCC LLW generated in the commercial sector or owned or generated by the federal government to the U.S. Department of Energy (DOE). At the time States were having difficulties in developing disposal facilities within the time constraints mandated in the LLWPA of 1980. Therefore, Congress believed that if DOE was assigned responsibility of developing disposal facilities for GTCC LLW, then the States would be more likely to develop new LLW disposal facilities. Congress also assigned the NRC with the responsibility to license the disposal of GTCC LLW generated or owned by the federal government or by the commercial sector. Lastly, Congress changed the definition of LLW that had been defined in the LLWPA of 1980 removing the 'transuranic' exclusionary language. Four years later, on May 25, 1989, the NRC promulgated its regulation needed to implement the mandates specified in the LLWPAA of 1985. The NRC revised 10 CFR 61.55 specifying that the NRC was responsible for licensing the disposal of GTCC LLW. However, it inadvertently did not revise the definition of LLW needed to remove the 'transuranic' exclusionary language in this rulemaking consistent with the LLWPAA of 1985. This seemingly inconsequential omission was not discovered until a Petition for Rulemaking was filed in Texas in July 2014. Moreover, this omission has effectively orphaned waste with certain transuranic radionuclides with concentrations exceeding 100 nanocuries per gram (100 nCi/g). In December 2015, the NRC Commissioners directed its staff to move forward with a rulemaking to resolve this issue and to perform a regulatory analysis to determine whether or not an Agreement State can license the disposal of GTCC LLW pursuant to Section 274 of the Atomic Energy Act of 1954. The paper will discuss past and current legislation, rulemaking, and regulatory developments pertaining to resolving the transuranic waste discrepancy and providing a pathway to disposition GTCC LLW. (authors)

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Correlation between low level fluctuations in the x ray background and faint galaxies

A correlation between low-level x-ray fluctuations in the cosmic x-ray background flux and the large numbers of galaxies found in deep optical imaging, to m(sub v) is less than or equal to 24 - 26, is desired. These (faint) galaxies by their morphology and color in deep multi-color CCD images and plate material were optically identified. Statistically significant correlations between these galaxies and low-level x-ray fluctuations at the same positions in multiple deep Einstein HRI observations in PAVO and in a ROSAT PSPC field were searched for. Our aim is to test the hypothesis that faint 'star burst' galaxies might contribute significantly to the cosmic x-ray background (at approximately 1 keV).

Tolstoy, Eline↗

Support of low-level instrument background for HPGe detectors

The development results for the cryostats with the low-level of instrument background supported by special design, the reduction of mass of the materials surrounding detector and application of the materials with very low content of radiation impurities are presented. The development results for HPGe detector with ultra low-level of instrument background for gamma spectrometer under the GEMMA project for investigation of the neutrino magnetic moment are presented. (authors)

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Preliminary Hazard Analysis for the Remote-Handled Low-Level Waste Disposal Project

The need for remote handled low level waste (LLW) disposal capability has been identified. A new onsite, remote-handled LLW disposal facility has been identified as the highest ranked alternative for providing continued, uninterrupted remote-handled LLW disposal capability for remote-handled LLW that is generated as part of the nuclear mission of the Idaho National Laboratory and from spent nuclear fuel processing activities at the Naval Reactors Facility. Historically, this type of waste has been disposed of at the Radioactive Waste Management Complex. Disposal of remote-handled LLW in concrete disposal vaults at the Radioactive Waste Management Complex will continue until the facility is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). This document supports the conceptual design for the proposed remote-handled LLW disposal facility by providing an initial nuclear facility hazard categorization and by identifying potential hazards for processes associated with onsite handling and disposal of remote-handled LLW.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Observational study of the South American low-level jet during the SALLJEX

The South American Low-Level Jet (SALLJ) east of the Andes is a narrow maximum northerly wind present just above the boundary layer. It is an important component of the tropical-extratropical exchange of heat and moisture in South America and favors deep moist convection in Southeastern South America (SESA). In the present study, the SALLJ characteristics during the 2002-2003 summer season are investigated using upper-air measurements collected during the SALLJ Experiment (SALLJEX). At most stations, the highest wind speed was observed below 3000 m between 06 and 12 UTC, mainly in association with a maximization of the northerly component of the wind while the zonal component reached its minimum. Here, an increase in the maximum wind speed from 10°S to Santa Cruz de la Sierra’s latitude and from there a weakening southward was found throughout the SALLJEX network. Additionally, SALLJEX observations allowed to locate SALLJ core purely from observations in a region just east of the Andes in agreement with previous studies. A new localized kinematic classification was developed and applied in this study to analyze the relationship between the SALLJ intensity and the thermodynamic properties of the lower layers of the atmosphere. Weak, moderate, and strong SALLJ categories were defined with a local threshold of the northerly wind speed maximum at each station. The strongest SALLJs were frequently observed at nighttime, while weaker SALLJs were likely to occur at any time of the day. A stabilization of the nocturnal boundary layer was observed between weak and moderate cases whereas a destabilization between moderate and strong cases were found near the time of the wind speed maximum (06 UTC) at Santiago del Estero and Resistencia stations. A deepening of the convective boundary layer and an increase of its mean temperature between weak and strong category during the previous afternoon to nocturnal SALLJs, reveal a possible contribution to the mechanisms that generate the maximum wind speed.

54 ENVIRONMENTAL SCIENCES↗

FY2019 Performance Assessment Annual Review for the E-Area Low-Level Waste Facility

The Savannah River Site (SRS) E-Area Low-Level Waste Facility (ELLWF) consists of six types of disposal units described in the Performance Assessment (PA) (WSRC, 2008): Low Activity Waste Vault (LAWV), Intermediate Level Vault (ILV), Trenches [Slit Trenches (STs), Engineered Trenches (ETs), and Component-in-Grout (CIG) Trenches], and Naval Reactor Component Disposal Areas (NRCDAs). The ELLWF is a part of the Solid Waste Management Facility (SWMF). SWMF is managed and operated by the SRS Management and Operations prime contractor, Savannah River Nuclear Solutions (SRNS). Within SRNS, the Solid Waste Management (SWM) organization is responsible for operating the SWMF, and the Savannah River National Laboratory (SRNL) is the technical agency responsible for preparing and maintaining the PA. SWMF operations have been performed at SRS since 1952. The mission of the SWMF is to provide storage, processing, disposal, and shipment of radioactive, hazardous, and mixed waste. The SWMF is committed to treat, store, and dispose of these waste products in a manner that protects the environment and the health and safety of the facility worker, the co-located worker, and the offsite general public. Wastes handled in the SWMF include low level waste, transuranic waste, hazardous waste, Toxic Substances Control Act waste, and mixed waste (containing both hazardous and radioactive constituents).

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FY2019 Performance Assessment Annual Review for the E-Area Low-Level Waste Facility

The Savannah River Site (SRS) E-Area Low-Level Waste Facility (ELLWF) consists of six types of disposal units described in the Performance Assessment (PA) (WSRC, 2008): Low Activity Waste Vault (LAWV), Intermediate Level Vault (ILV), Trenches [Slit Trenches (STs), Engineered Trenches (ETs), and Component-in-Grout (CIG) Trenches], and Naval Reactor Component Disposal Areas (NRCDAs). The ELLWF is a part of the Solid Waste Management Facility (SWMF). SWMF is managed and operated by the SRS Management and Operations prime contractor, Savannah River Nuclear Solutions (SRNS). Within SRNS, the Solid Waste Management (SWM) organization is responsible for operating the SWMF, and the Savannah River National Laboratory (SRNL) is the technical agency responsible for preparing and maintaining the PA. SWMF operations have been performed at SRS since 1952. The mission of the SWMF is to provide storage, processing, disposal, and shipment of radioactive, hazardous, and mixed waste. The SWMF is committed to treat, store, and dispose of these waste products in a manner that protects the environment and the health and safety of the facility worker, the co-located worker, and the offsite general public. Wastes handled in the SWMF include low level waste, transuranic waste, hazardous waste, Toxic Substances Control Act waste, and mixed waste (containing both hazardous and radioactive constituents).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

An Evaluation of Long-Term Performance of Liner Systems for Low-Level Waste Disposal Facilities

Traditional liner systems consisting of a geosynthetic membrane underlying a waste disposal facility coupled with a leachate collection system have been proposed as a means of containing releases of low-level radioactive waste within the confines of the disposal facility and thereby eliminating migration of radionuclides into the vadose zone and groundwater. However, this type of hydraulic containment liner system is only effective as long as the leachate collection system remains functional or an overlying cover limits the total infiltration to the volumetric pore space of the disposal system. If either the leachate collection system fails, or the overlying cover becomes less effective during the 1,000’s of years of facility lifetime, the liner may fill with water and release contaminated water in a preferential or focused manner. If the height of the liner extends above the waste, the waste will become submerged which could increase the release rate and concentration of the leachate. If the liner extends near land surface, there is the potential for contamination reaching land surface creating a direct exposure pathway. Alternative protective liner systems can be engineered that eliminate radionuclide releases to the vadose zone during operations and minimizing long term migration of radionuclides from the disposal facility into the vadose zone and aquifer. Non-traditional systems include waste containerization in steel or composite materials. This type of system would promote drainage of clean infiltrating water through the facility without contacting the waste. Other alternatives include geochemical barriers designed to transmit water while adsorbing radionuclides beneath the facility. Facility performance for a hypothetical disposal facility has been compared for the hydraulic and steel containerization liner alternatives. Results were compared in terms of meeting the DOE Order 435.1 low-level waste performance objective of 25 mrem/yr all-pathways dose during the 1) institutional control period (0-100 years), compliance period (0-1000 years) and post-compliance period (>1000 years). Evaluation of the all pathway dose included the dose from ingestion and irrigation of contaminated groundwater extracted from a well 100 meters downgradient, in addition to the dose received from direct contact of radionuclides deposited near the surface resulting from facility overflow. Depending on the disposal facility radionuclide inventory, facility design, cover performance, and the location and environment where the facility is situated, the dose from exposure via direct contact of near surface deposited radionuclides can be much greater than the dose received via transport to the groundwater and subsequent ingestion.

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Explanation of Significant Differences Between Models used to Assess Groundwater Impacts for the Disposal of Greater-Than-Class C Low-Level Radioactive Waste and Greater-Than-Class C-Like Waste Environmental Impact Statement (DOE/EIS-0375-D) and the

Models have been used to assess the groundwater impacts to support the Draft Environmental Impact Statement for the Disposal of Greater-Than-Class C (GTCC) Low-Level Radioactive Waste and GTCC-Like Waste (DOE-EIS 2011) for a facility sited at the Idaho National Laboratory and the Environmental Assessment for the INL Remote-Handled Low-Level Waste Disposal Project (INL 2011). Groundwater impacts are primarily a function of (1) location determining the geologic and hydrologic setting, (2) disposal facility configuration, and (3) radionuclide source, including waste form and release from the waste form. In reviewing the assumptions made between the model parameters for the two different groundwater impacts assessments, significant differences were identified. This report presents the two sets of model assumptions and discusses their origins and implications for resulting dose predictions. Given more similar model parameters, predicted doses would be commensurate.

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Stakeholder Engagement on the Environmental Impact Statement for the Disposal of Greater-Than-Class C Low-Level Radioactive Waste -12565

The Department of Energy's (DOE) Office of Disposal Operations is responsible for developing a permanent disposal capability for a small volume, but highly radioactive, class of commercial low-level radioactive waste, known as Greater-Than-Class C (GTCC) low-level radioactive waste. DOE has issued a draft environmental impact statement (EIS) and will be completing a final EIS under the National Environmental Policy Act (NEPA) that evaluates a range of disposal alternatives. Like other classes of radioactive waste, proposing and evaluating disposal options for GTCC waste is highly controversial, presents local and national impacts, and generates passionate views from stakeholders. Recent national and international events, such as the cancellation of the Yucca Mountain project and the Fukushima Daiichi nuclear accident, have heighten stakeholder awareness of everything nuclear, including disposal of radioactive waste. With these challenges, the Office of Disposal Operations recognizes that informed decision-making that will result from stakeholder engagement and participation is critical to the success of the GTCC EIS project. This paper discusses the approach used by the Office of Disposal Operations to engage stakeholders on the GTCC EIS project, provides advice based on our experiences, and proffers some ideas for future engagements in today's open, always connected cyber environment. (authors)

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Synergistic interactions between an upper-level jet streak and diabatic processes that influence the development of a low-level jet and a secondary coastal cyclone

A series of numerical simulations of the February 1979 Presidents Day cyclone is presented. The development of the low-level jet (LLJ) associated with the cyclone is described, and the mesoscale numerical model, initial analyses, and experimental design used in the study are discussed. Four numerical simulations are discussed and compared, including an adiabatic simulation that isolates the development of upper-level divergence along the axis of a subtropical jet streak and three other simulations that reveal the contributions of sensible and latent heat release in modifying lower-tropospheric wind fields and reducing the sea-level pressure. The formation of the LLJ is described through an evaluation of trajectories derived from the various model simulations. The effect of the LLJ on secondary cyclogenesis along the East Coast is described.

Uccellini, Louis W.↗