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

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At least 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Nevada National Security Site Integrated Groundwater Sampling Plan, Revision 1

The purpose is to provide a comprehensive, integrated approach for collecting and analyzing groundwater samples to meet the needs and objectives of the DOE/EM Nevada Program’s UGTA Activity. Implementation of this Plan will provide high-quality data required by the UGTA Activity for ensuring public protection in an efficient and cost-effective manner. The Plan is designed to ensure compliance with the UGTA Quality Assurance Plan (QAP) (NNSA/NFO, 2015); Federal Facility Agreement and Consent Order (FFACO) (1996, as amended); and DOE Order 458.1, Radiation Protection of the Public and the Environment (DOE, 2013). The Plan’s scope comprises sample collection and analysis requirements relevant to assessing both the extent of groundwater contamination from underground nuclear testing and impact of testing on water quality in downgradient communities. This Plan identifies locations to be sampled by CAU and location type, sampling frequencies, sample collection methodologies, and the constituents to be analyzed. In addition, the Plan defines data collection criteria such as well purging, detection levels, and accuracy requirements/recommendations; identifies reporting and data management requirements; and provides a process to ensure coordination between NNSS groundwater sampling programs for sampling analytes of interest to UGTA. Information used in the Plan development—including the rationale for selection of wells, sampling frequency, and the analytical suite—is discussed under separate cover (N-I, 2014) and is not reproduced herein. This Plan does not address compliance for those wells involved in a permitted activity. Sampling and analysis requirements associated with these wells are described in their respective permits and are discussed in NNSS environmental reports (see Section 5.2). In addition, sampling for UGTA CAUs that are in the Closure Report (CR) stage are not included in this Plan. Sampling requirements for these CAUs are described in the CR. Frenchman Flat is currently the only UGTA CAU in the CR stage. Sampling requirements for this CAU are described in Underground Test Area (UGTA) Closure Report for Corrective Action Unit 98: Frenchman Flat Nevada National Security Site, Nevada (NNSA/NFO, 2016).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Nevada National Security Site Integrated Groundwater Sampling Plan, Revision 1, with ROTC-1

The purpose of the Nevada National Security Site (NNSS) Integrated Groundwater Sampling Plan (referred to herein as the Plan) is to provide a comprehensive, integrated approach for collecting and analyzing groundwater samples to meet the needs and objectives of the U.S. Department of Energy (DOE), Environmental Management (EM) Nevada Program’s Underground Test Area (UGTA) Activity. Implementation of this Plan will provide high-quality data required by the UGTA Activity for ensuring public protection in an efficient and cost-effective manner. The Plan is designed to ensure compliance with the UGTA Quality Assurance Plan (QAP) (NNSA/NFO, 2015). The Plan’s scope comprises sample collection and analysis requirements relevant to assessing both the extent of groundwater contamination from underground nuclear testing and impact of testing on water quality in downgradient communities. This Plan identifies locations to be sampled by corrective action unit (CAU) and location type, sampling frequencies, sample collection methodologies, and the constituents to be analyzed. In addition, the Plan defines data collection criteria such as well purging, detection levels, and accuracy requirements/recommendations; identifies reporting and data management requirements; and provides a process to ensure coordination between NNSS groundwater sampling programs for sampling analytes of interest to UGTA. Information used in the Plan development—including the rationale for selection of wells, sampling frequency, and the analytical suite—is discussed under separate cover (N-I, 2014) and is not reproduced herein.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Evaluation of Fire Station 23-425, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada

The U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office (NNSA/NFO) plans to modernize the Mercury town site at the Nevada National Security Site (NNSS) in Nye County, Nevada, to meet current and future National Weapons Science, Global and Homeland Security Programs, and Environmental Management mission requirements. These plans—including anticipated demolitions, consolidations, and rebuilding at Mercury—are considered an undertaking subject to review under Title 54 U.S.C. § 306108, commonly known as Section 106 of the National Historic Preservation Act, Title 54 U.S.C. § 300101, et seq., and its implementing regulations, 36 C.F.R. Part 800. Desert Research Institute (DRI) completed an architectural survey of Mercury. This effort resulted in the identification, recordation, and evaluation of the Mercury Historic District, including the identification of its contributing components. This district was recommended eligible for listing to the National Register of Historic Places (NRHP or National Register) under Criteria A and C but was unevaluated under Criteria B and D at that time. The Mercury Historic District contains 153 individual landscapes, buildings, and structures. Of these resources, all except one are recommended as contributing elements of the historic district during its period of significance corresponding to nuclear testing from 1951 through 1992. During most of the Cold War, the land now called the NNSS was named the Nevada Test Site (NTS). This report concerns the proposed demolition of the 1966 Fire Station 23-425 in Mercury as a phase of the larger modernization program mentioned above. Further evaluation of this property indicates that it does not meet any of the Secretary of the Interior’s Significance Criteria for eligibility for the NRHP at either the national or local levels. However, it does remain an important contributing element of Mercury Historic District. This is part of a series of reports.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Evaluation of 1950s-Era Architectural Resources in Blocks 10, 11, and 17, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada

The U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office (NNSA/NFO) plans to modernize the Mercury town site at the Nevada National Security Site (NNSS) in Nye County, Nevada, to meet current and future National Weapons Science, Global and Homeland Security Programs, and Environmental Management mission requirements. These plans, including anticipated demolitions, consolidations, and rebuilding at Mercury, are considered an undertaking subject to review under Title 54 U.S.C. § 306108, commonly known as Section 106 of the National Historic Preservation Act, Title 54 U.S.C. § 300101, et seq., and its implementing regulations, 36 C.F.R. Part 800. The Desert Research Institute (DRI) completed an architectural survey of Mercury. This effort resulted in the identification, recording, and evaluation of the Mercury Historic District (Nevada State Historic Preservation Office [SHPO] Resource No. D230), including the identification of its contributing components (Reno et al. 2018). This district was recommended eligible to the National Register of Historic Places (NRHP or National Register) under Criteria A and C but was unevaluated under Criteria B and D at that time. The Mercury Historic District contains 154 individual landscapes, buildings, and structures. Of these resources, DRI recommends all except one as contributing elements of the historic district during its period of significance corresponding to nuclear testing from 1951 through 1992. During most of the Cold War, the land now called the NNSS was formerly the Nevada Test Site (NTS). This report is concerned with evaluating resources dating to the 1950s in Blocks 10, 11, and 17 in Mercury prior to the proposed demolition of 22 resources in Blocks 10 and 11 as a phase of the larger modernization program mentioned above. Although the Mercury Historic District as a whole is eligible to the National Register, further evaluation of these properties as detailed in this report indicates that none are individually eligible under any of the Secretary of Interior’s Significance Criteria, either at the national or local level. This is one report in the report series "Evaluation, Finding of Effect, and Mitigation Documentation for 1950s-Era Architectural Resources, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada".

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

A Section 110 Evaluation of the Project 57 Rad-Safe Area Personnel Decontamination Building, Nye County, Nevada

Project 57 was an open-air, plutonium-dispersal safety test conducted by the United States in 1957 on a portion of the Nevada Test and Training Range (NTTR) (formerly the Las Vegas Bombing and Gunnery Range). The Project 57 test area, once known as Area 13, was a block of land abutting the northeastern boundary of the Nevada Test Site (NTS). The NTS was renamed the Nevada National Security Site (NNSS) in 2010. In keeping with the historical Cold War period designation, NTS will be used when discussing historic period events, while NNSS will be applied for contemporary activities. During Project 57, the high explosives of a nuclear weapon were triggered asymmetrically to simulate an accidental detonation. The test was conducted to study the extent of plutonium contamination from a nonnuclear yield accident, as well as assess the biological and environmental hazards such an event could create. Following the conclusion of the experiment, the contaminated area surrounding the ground zero (GZ) was fenced off and some of the contaminated equipment was buried in place. The Project 57 Rad-Safe area was abandoned. In 1981, the U.S. Department of Energy (DOE) decontaminated and decommissioned the Project 57 site. This Section 110 documentation was prompted by recognition that more than five decades have passed since the abandonment of the Project 57 Rad-Safe area, particularly the personnel decontamination building, which leaves the temporary structure vulnerable to natural forces of weathering and decay. However, these temporary facilities remain partially standing, allowing for a condition assessment and recommendations regarding the Rad-Safe area’s historical significance. The National Nuclear Security Administration, Nevada Field Office (NNSA/NFO) determined there was no area of potential effect (APE) (direct, indirect, or visual) because there is no planned undertaking and the Project 57 Rad-Safe area will continue to remain unused. Instead, a 4.5-acre study area was established to facilitate recording the Project 57 personnel decontamination building and the remaining accessory resources. The study area is bounded on the east by Valley Road and it extends to the east far enough to encompass the former Project 57 Rad-Safe area (Figure A-2). The Section 110 study area is located in the northwest quarter of Section 35, Township 07S Range 54E Mount Diablo Base and Meridian. It is on the 1962 Groom Mine SW USGS 7.5-minute series topographic quadrangle. Desert Research Institute (DRI) surveyed the Section 110 study area, resulting in the recording and evaluation of the Project 57 Rad-Safe area personnel decontamination building and four accessory resources (AR-1 through AR-4). Copies of the building form and report are on file at DRI and with the NNSA/NFO in Las Vegas, Nevada.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Report series: Evaluation, Finding of Effect, and Mitigation Documentation for the 1960s Dormitories and 1950s Quonset Hut Foundations, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada [3 Reports Consolidated]

The U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office (NNSA/NFO) plans to modernize the town of Mercury at the Nevada National Security Site (NNSS) in Nye County, Nevada, to meet current and future National Weapons Science, Global and Homeland Security Programs, and Environmental Management mission requirements. These plans—including anticipated demolitions, consolidations, and rebuilding at Mercury—are considered an undertaking subject to review under Title 54 U.S.C. § 306108, commonly known as Section 106 of the National Historic Preservation Act, Title 54 U.S.C. § 300101, et seq., and its implementing regulations, 36 C.F.R. Part 800. Desert Research Institute (DRI) completed an architectural survey of Mercury in 2017. This effort resulted in the identification, recording, and evaluation of the Mercury Historic District, as well as the identification of its contributing components. This district was recommended eligible to the National Register of Historic Places (NRHP or National Register) under Criteria A and C, but was unevaluated under Criteria B and D at that time. The Mercury Historic District contains 153 individual landscapes, buildings, and structures. Of these resources, DRI recommends all except one as contributing elements of the historic district during its period of significance corresponding to nuclear testing from 1951 through 1992. During most of the Cold War, the land now called the NNSS was referred to as the Nevada Test Site (NTS). This report evaluates resources dating to the 1950s and 1960s between Jangle and Knothole Streets and south of Ranger Avenue in Mercury prior to the proposed demolition of all resources in that area between Sandstone and Greenhouse Avenues as a phase of the larger modernization program mentioned above. Although the Mercury Historic District as a whole is eligible to the National Register, further evaluation of these properties, as detailed in this report, indicates that none are individually eligible under any of the Secretary of Interior’s Significance Criteria, either at the national or local level.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

INL Waste Management Program Assessment Report

This is an INL annual internal waste management program assessment report that will need to be sent to NNSS for review. The report includes a summary and completed checklists based on the NNSS Waste Acceptance Criteria.

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DOE OSTI2021

Nevada National Security Site Demonstration Reactor Siting and Capability Study

The study’s purpose is to identify suitable testbeds within the NNSS for the demonstration of advanced and emerging reactor technologies. These testbeds are envisioned to be existing structures, facilities, or sites that may be suitable for advanced reactor demonstrations, advanced reactor fuel fabrication, or other experimental support for advanced reactor demonstrations. This study examines siting alternatives at NNSS with the objective of identifying locations for near term ARD projects. Included in the outcomes is an evaluation of the quantitative and qualitative factors that must be addressed for each site if selected to host an ARD sponsored demonstration.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2022

Report Series: Finding of Effect and Mitigation Documentation for Building 23-153, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada

Finding of Effect: The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) plans to demolish Building 23-153, the Mechanical Calibration Laboratory (Calibration Lab), in Mercury (Nevada State Historic Preservation Office [SHPO] Resource No. B15271), which is on the Nevada National Security Site (NNSS) in Nye County, Nevada. The purpose of the undertaking is related to the modernization of Mercury for future mission needs. The NNSA/NFO will implement this undertaking in accordance with the Programmatic Agreement between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer Regarding Modernization and Operational Maintenance of the Nevada National Security Site, at Mercury in Nye County, Nevada, hereafter referred to as the Mercury PA. Building 23-153 was constructed in Mercury in 1982 as the Mechanical Calibration Laboratory and served as a support facility for nuclear testing throughout the last decade of the Cold War. The town of Mercury and the immediate surrounding area have been formally determined eligible for listing in the National Register of Historic Places (NRHP) as the Mercury Historic District (MHD, SHPO Resource No. D230) under Criteria A and C for their importance in supporting nuclear testing and scientific research from 1951 through 1992. Building 23-153 was identified as a contributing element to the MHD in a 2018 architectural survey of the district (Reno et al. 2018) and recorded on a Nevada Architectural Resource Assessment (ARA) form (Reno et al. 2017). Building 23-153 was also identified in Appendix C of the Mercury PA as a Category II contributing element. Category II properties are those that have several representatives in the MHD but may possess different engineering or architectural characteristics that distinguish them from other classes of similar elements. Building 23-153 is a historic property for the purposes of compliance with Section 106 of the National Historic Preservation Act (NHPA) and subject to the stipulations of the Mercury PA. Mitigation: The purpose of this letter report is to submit documentation related to the mitigation of the demolition of Building 23-153, the Mechanical Calibration Laboratory (Calibration Lab, Nevada State Historic Preservation Office [SHPO] Resource No. B15271), in the Mercury Historic District (MHD, SHPO Resource No. D230) at the Nevada National Security Site (NNSS) in Nye County, Nevada. The Calibration Lab is considered contributing to the significance of the district both for its historic importance in relation to nuclear testing under Criterion A and as a part of the distinctive design and construction of the district under Criterion C. This submission is intended to comply with the stipulations in the Programmatic Agreement between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer Regarding Modernization and Operational Maintenance of the Nevada National Security Site, at Mercury in Nye County, Nevada, hereafter referred to as the Mercury PA.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Finding of Adverse Effect and Proposed Mitigation for the Demolition of Building 23-530, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada

The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) plans to demolish Building 23-530 in Mercury (Nevada State Historic Preservation Office [SHPO] Resource No. B15270), which is on the Nevada National Security Site (NNSS) in Nye County, Nevada. The purpose of the undertaking is related to the modernization of Mercury for future mission needs. The NNSA/NFO will implement this undertaking in accordance with the Programmatic Agreement Between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer Regarding Modernization and Operational Maintenance of the Nevada National Security Site, at Mercury in Nye County, Nevada, hereafter referred to as the Mercury PA. Building 23-530, a dormitory called Freedom Hall, was constructed in Mercury in 1982 and served as a support facility for nuclear testing for the last decade of the Cold War. The town of Mercury and the immediate surrounding area have been determined eligible for listing in the National Register of Historic Places (NRHP) as the Mercury Historic District (MHD, SHPO Resource No. D230) under Criteria A and C for their importance in supporting nuclear testing and scientific research from 1951 through 1992 (Reed 2019). Building 23-530 was identified as a contributing element to the MHD in a 2018 architectural survey of the district (Reno et al. 2018) and recorded on a Nevada Architectural Resource Assessment (ARA) form (Reno et al. 2017). Building 23-530 was also identified in Appendix C of the Mercury PA as a Category II contributing element. Category II properties are those that have several representatives in the MHD but may possess different engineering or architectural characteristics that distinguish them from other classes of similar elements. Building 23-530 is a historic property for the purposes of compliance with Section 106 of the National Historic Preservation Act (NHPA) and subject to the stipulations of the Mercury PA. The purpose of this letter report is to submit documentation related to the mitigation of the demolition of Building 23-530 (Nevada State Historic Preservation Office [SHPO] Resource No. B15270) in the Mercury Historic District (MHD, SHPO Resource No. D230) at the Nevada National Security Site (NNSS) in Nye County, Nevada. The dormitory is considered contributing to the significance of the district both for its historic importance in relation to nuclear testing under Criterion A and as a part of the distinctive design and construction of the district under Criterion C. This submission is intended to comply with the stipulations in the Programmatic Agreement between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer Regarding Modernization and Operational Maintenance of the Nevada National Security Site, at Mercury in Nye County, Nevada, hereafter referred to as the Mercury PA.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Finding of No Adverse Effect for the Façade Alteration of Building 23-117, Administration Building, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada

The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) plans to update the façade of Building 23-117 in the town of Mercury (Nevada State Historic Preservation Office [SHPO] Resource No. B15256), which is on the Nevada National Security Site (NNSS) in Nye County, Nevada. The purpose of the undertaking is to incorporate Building 23-117 into the new Mercury campus in accordance with the master plan for the modernization of Mercury. The NNSA/NFO will implement this undertaking in accordance with the Programmatic Agreement between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer Regarding Modernization and Operational Maintenance of the Nevada National Security Site, at Mercury in Nye County, Nevada, hereafter referred to as the Mercury PA. Building 23-117 was built in 1982 as the architect-engineer Administration Building1 for Holmes & Narver, a government contractor who helped design and engineer the town of Mercury and other areas on the NNSS from its inception until the termination of their contract in 1990. The building continued to be used by subsequent government contractors and is currently still in use by MSTS. The town of Mercury and the immediate surrounding area have been formally determined eligible for listing in the National Register of Historic Places (National Register, NRHP) as the Mercury Historic District (MHD, SHPO Resource No. D230) under Criteria A and C for its importance in supporting nuclear testing and scientific research from 1951 through 1992. Building 23-117 was identified as a contributing element to the MHD in a 2018 architectural survey of the district (Reno et al.) and recorded on a Nevada Architectural Resource Assessment (ARA) form (Reno et al. 2017). It is a historic property for the purposes of compliance with Section 106 of the National Historic Preservation Act (NHPA) and is subject to the stipulations of the Mercury PA. The NNSA/NFO requested that Desert Research Institute (DRI), cultural resource subject matter experts, analyze the effects of the proposed project on historic properties in the Area of Potential Effect (APE) and make a recommended finding for the undertaking in accordance with Section 106 of the NHPA and the Mercury PA. The purpose of this letter report is to submit documentation related to the mitigation of the façade alteration of Building 23-117 (Nevada State Historic Preservation Office [SHPO] Resource No. B15256) in the Mercury Historic District (MHD, SHPO Resource No. D230). This submission is intended to comply with the stipulations in the Programmatic Agreement between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer Regarding Modernization and Operational Maintenance of the Nevada National Security Site at Mercury in Nye County, Nevada, hereafter referred to as the Mercury PA.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Special Analysis for the Disposal of the Lawrence Livermore National Laboratory EnergyX Macroencapsulated Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) EnergyX Macroencapsulated waste stream (B LAMACRONCAP, Revision 1) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL EnergyX Macroencapsulated waste stream is macroencapsulated mixed waste generated during research laboratory operations and maintenance (LLNL 2015). The LLNL EnergyX Macroencapsulated waste stream required a special analysis due to tritium (3H), cobalt-60 (60Co), cesium-137 (137Cs), and radium-226 (226Ra) exceeding the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015).The results indicate that all performance objectives can be met with disposal of the waste stream in a SLB trench. Addition of the LLNL EnergyX Macroencapsulated inventory slightly increases multiple performance assessment results, with the largest relative increase occurring for the all-pathways annual total effective dose (TED). The maximum mean and 95th percentile 222Rn flux density remain less than the performance objective throughout the compliance period. The LLNL EnergyX Macroencapsulated waste stream is suitable for disposal by SLB at the Area 5 RWMS. The waste stream is recommended for approval without conditions.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Special Analysis for the Disposal of the Lawrence Livermore National Laboratory Low Activity Beta/Gamma Sources Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) Low Activity Beta/Gamma Sources waste stream (BCLALADOEOSRP, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL Low Activity Beta/Gamma Sources waste stream consists of sealed sources that are no longer needed. The LLNL Low Activity Beta/Gamma Sources waste stream required a special analysis because cobalt-60 (60Co), strontium-90 (90Sr), cesium-137 (137Cs), and radium-226 (226Ra) exceeded the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015). The results indicate that all performance objectives can be met with disposal of the LLNL Low Activity Beta/Gamma Sources in a SLB trench. The LLNL Low Activity Beta/Gamma Sources waste stream is suitable for disposal by SLB at the Area 5 RWMS. However, the activity concentration of 226Ra listed on the waste profile sheet significantly exceeds the action level. Approval of the waste profile sheet could potentially allow the disposal of high activity 226Ra sources. To ensure that the generator does not include large 226Ra sources in this waste stream without additional evaluation, a control is need on the maximum 226Ra inventory. A limit based on the generator’s estimate of the total 226Ra inventory is recommended. The waste stream is recommended for approval with the control that the total 226Ra inventory disposed shall not exceed 5.5E10 Bq (1.5 Ci).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Special Analysis for the Disposal of the Sandia National Laboratory Classified Macroencapsulated Mixed Waste at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

This special analysis evaluates whether the Sandia National Laboratory (SNL) Classified Macroencapsulated Mixed Waste stream (ASLA000001007, Revision 4) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The SNL Classified Macroencapsulated Mixed Waste stream consists of debris from classified nuclear weapons components (SNL 2015). The SNL Classified Macroencapsulated Mixed Waste stream required a special analysis due to tritium (3H) exceeding the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015). The SNL Classified Macroencapsulated Mixed Waste stream had no significant effect on the maximum mean and 95th percentile results for the resident air pathway and all-pathways annual total effective dose (TED). The SNL Classified Macroencapsulated Mixed Waste stream increases the mean air pathway and all-pathways annual TED from approximately 100 to 200 years after closure. Addition of the SNL Classified Macroencapsulated Mixed Waste stream inventory shifts the maximum TED to approximately 100 years after closure and increases the TED for several alternative exposure scenarios. The maximum mean and the 95th percentile 222Rn flux density remain less than the performance objective throughout the compliance period. The SNL Classified Macroencapsulated Mixed Waste stream is suitable for disposal by SLB at the Area 5 RWMS. The waste stream is recommended for approval without conditions.

LNL↗
DOE OSTI2025

Nevada National Security Site Environmental Report 2024 with Attachment A Site Description

The Nevada National Security Site Environmental Report 2024 Attachment A report expands on the general description of the Nevada National Security Site (NNSS) presented in the Introduction to the Nevada National Security Site Environmental Report 2024. Included are subsections that summarize the site’s geological, hydrological, climatological, and ecological settings and the cultural resources of the NNSS.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Comparison of experimental methods for estimating matrix diffusion coefficients for contaminant transport modeling

Here, diffusion cell and diffusion wafer experiments were conducted to compare methods for estimating effective matrix diffusion coefficients in rock core samples from Pahute Mesa at the Nevada Nuclear Security Site (NNSS). A diffusion wafer method, in which a solute diffuses out of a rock matrix that is pre-saturated with water containing the solute, is presented as a simpler alternative to the traditional through-diffusion (diffusion cell) method. Both methods yielded estimates of effective matrix diffusion coefficients that were within the range of values previously reported for NNSS volcanic rocks. The difference between the estimates of the two methods ranged from 14 to 30%, and there was no systematic high or low bias of one method relative to the other. From a transport modeling perspective, these differences are relatively minor when one considers that other variables (e.g., fracture apertures, fracture spacings) influence matrix diffusion to a greater degree and tend to have greater uncertainty than effective matrix diffusion coefficients. For the same relative random errors in concentration measurements, the diffusion cell method yields effective matrix diffusion coefficient estimates that have less uncertainty than the wafer method. However, the wafer method is easier and less costly to implement and yields estimates more quickly, thus allowing a greater number of samples to be analyzed for the same cost and time. Given the relatively good agreement between the methods, and the lack of any apparent bias between the methods, the diffusion wafer method appears to offer advantages over the diffusion cell method if better statistical representation of a given set of rock samples is desired.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Impulse response measurements of fast scintillator-based current mode detectors

In this study, experimental measurements were performed to characterize the impulse response of seven different gamma ray detector prototypes being considered to be fielded as a current mode diagnostic for neutron-diagnosed subcritical experiments at the Nevada National Security Site (NNSS). For such experiments, the impulse response of the fielded detector is required to have a full-width half-maximum (FWHM) of approximately 5 ns or less and a low amplitude tail. Each of the detector prototypes evaluated in this work were selected based on the potential to meet this performance requirement. An impulse of bremsstrahlung x-rays created from 2 MeV electrons from the NNSS’s Transformational Diagnostics and Imaging, Los Alamos, linear accelerator was measured with each detector. The measured impulse response was evaluated for each detector configuration. A comparison of these impulse responses revealed a relationship between fast timing performance and scintillator material, geometry, surface reflectivity conditions, and photomultiplier tube (PMT) selection. The detector configuration yielding an impulse response with the shortest FWHM of 3.82 ± 0.11 ns and possessing a low amplitude tail was a 5-inch (12.7-cm) diameter, 5-inch (12.7-cm) height cylindrical EJ-399-17-VI liquid scintillator in a black-painted housing coupled to an Adit D798B 5-inch (12.7-cm) PMT by means of a 0.079-inch (0.2-cm) EJ-560 optical coupling pad.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2016

Plutonium Interactions with Pseudomonas sp. and its Extracellular Polymeric Substances (Sorption and Reduction of Plutonium by Bacterial Extracellular Polymeric Substances)

Safe and effective nuclear waste disposal, as well as accidental radionuclide releases, necessitates our understanding of the fate of radionuclides in the environment, including their interaction with microorganisms. We examined the sorption of Pu(IV) and Pu(V) to Pseudomonas sp. strain EPS-1W, an aerobic bacterium isolated from plutonium (Pu) contaminated groundwater collected in the United States at the Nevada National Security Site (NNSS), Nevada. We compared Pu sorption to cells with and without bound extracellular polymeric substances (EPS). Wild type cells with intact EPS sorbed Pu(V) more effectively than cells with EPS removed. In contrast, cells with and without EPS showed the same sorption affinity for Pu(IV). In vitro experiments with extracted EPS revealed rapid reduction of Pu(V) to Pu(IV). Transmission Electron Microscopy indicated that 2-3 nm nanocrystalline Pu(IV)O 2 formed on cells equilibrated with high concentrations of Pu(IV) but not Pu(V). Thus, EPS, while facilitating Pu(V) reduction, inhibit the formation of nanocrystalline Pu(IV) precipitates. Importance Our results indicate that EPS are an effective reductant for Pu(V) and sorbent for Pu(IV), and may impact Pu redox cycling and mobility in the environment. Additionally, the resulting Pu morphology associated with EPS will depend on the concentration and initial Pu oxidation state. While our results are not directly applicable to the Pu transport situation at the NNSS, the results suggest that, in general, stationary microorganisms and biofilms will tend to limit the migration of Pu and provide an important Pu retardation mechanism in the environment. In a broader sense, our results along with a growing body of literature highlight the important role of microorganisms as producers of redox-active organic ligands and therefore as modulators of radionuclide redox transformations and complexation in the subsurface.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗