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NASA NTRS2023

A Data-driven, Physics-based Transport Model of Solar Energetic Particles Accelerated by Coronal Mass Ejection Shocks Propagating through the Solar Coronal and Heliospheric Magnetic Fields

In an effort to develop computational tools for predicting radiation hazards from solar energetic particles (SEPs), we have created a data-driven physics-based particle transport model to calculate the injection, acceleration, and propagation of SEPs from coronal mass ejection (CME) shocks traversing through the solar corona and interplanetary magnetic fields. The model runs on an input of corona and heliospheric plasma and magnetic field configuration from a magnetohydrodynamic model driven by solar photospheric magnetic field measurements superposed with observed CME shocks determined from coronagraph images. SEP source particles are injected at the shock using the result of diffusive shock acceleration formulation from a characteristic obliquity-dependent injection from a heated solar wind thermal tail population. With several advanced computation techniques involving stochastic simulation and integration, the model obtains the particle intensity at any location in interplanetary space through the rigorous solution to the time-dependent 5D focus transport equation in the phase space that includes perpendicular diffusion. We apply the model to the 2011 November 3 CME event. The calculation results reproduce multispacecraft SEP observations at Earth and STEREO-B reasonably well without normalization of particle flux. The observations at STEREO-A can be reproduced by rescaling particle energy or modified energy dependence of particle diffusion coefficients. This circumsolar SEP event seen by spacecraft at Earth, STEREO-A, and STEREO-B at widely separated longitudes can be explained by diffusive shock acceleration by a single CME shock with a moderate speed.

Solar energetic particles↗
NASA NTRS2024

NASA Risk Management Handbook: Version 2.0, Part 1

The purpose of this handbook is to provide an in-depth reference for the practice of risk management in NASA, updating the guidance offered in its original version, NASA/SP-2011-3422 (November 2011), and closely aligning the updated guidance with the current NASA Procedural Requirements for Agency Risk Management, NPR 8000.4, and the parent NASA Policy Directive for NASA Governance and Strategic Management, NPD 1000.0. NPD 1000.0 introduces with emphasis the concept of “Risk Leadership,” making it a fundamental tenet and pillar of the risk management culture that it advocates for the Agency. NPR 8000.4 applies this concept and establishes Risk Management (RM) requirements for the Agency as an integrated enterprise, as well as the RM requirements for portfolio elements within the enterprise. Such elements include the various programs and projects that contribute to the Agency’s objectives and the various institutional activities carried out by entities that contribute to mission support. The present version of the handbook also emphasizes the integration of risk management processes across activity and project life cycles and their coordination and interaction with day-to-day programmatic and organizational functions. Areas of application of risk assessment and management that were not covered with specific guidance in the preceding version are addressed in this version with in-depth examples. The handbook is structured into two parts, whose chapters are in turn organized in a sequential order intended to facilitate a gradual and progressive introduction of the reader to risk management principles and practices. Part 1 of the handbook is dedicated to the introduction of the basic foundations of the NASA integrated risk management framework, the related fundamental risk concepts, the description of the risk management and decision processes that are to be implemented within the framework, the discussion of the risk assessment techniques that should be utilized in support of such processes, and the management and organizational interactions and interfaces that should be enabled to implement an effective integration of risk management activities within the Agency. Part 2 provides self-contained, end-to-end examples of application of the processes and techniques introduced in Part 1, in the context of both programmatic (i.e., project and/or mission related) and institutional activities.

Uncertainty↗
NASA NTRS2024

NASA Risk Management Handbook: Version 2.0, Part 2

The purpose of this handbook is to provide an in-depth reference for the practice of risk management in NASA, updating the guidance offered in its original version, NASA/SP-2011-3422 (November 2011), and closely aligning the updated guidance with the current NASA Procedural Requirements for Agency Risk Management, NPR 8000.4, and the parent NASA Policy Directive for NASA Governance and Strategic Management, NPD 1000.0 (January 2020). NPD 1000.0 introduces with emphasis the concept of “Risk Leadership,” making it a fundamental tenet and pillar of the risk management culture that it advocates for the Agency. NPR 8000.4 applies this concept and establishes Risk Management (RM) requirements for the Agency as an integrated enterprise, as well as the RM requirements for portfolio elements within the enterprise. Such elements include the various programs and projects that contribute to the Agency’s objectives and the various institutional activities carried out by entities that contribute to mission support. The present version of the handbook also emphasizes the integration of risk management processes across activity and project life cycles and their coordination and interaction with day-to-day programmatic and organizational functions. Areas of application of risk assessment and management that were not covered with specific guidance in the preceding version are addressed in this version with in-depth examples. The handbook is structured into two parts, whose chapters are in turn organized in a sequential order intended to facilitate a gradual and progressive introduction of the reader to risk management principles and practices. Part 1 of the handbook is dedicated to the introduction of the basic foundations of the NASA integrated risk management framework, the related fundamental risk concepts, the description of the risk management and decision processes that are to be implemented within the framework, the discussion of the risk assessment techniques that should be utilized in support of such processes, and the management and organizational interactions and interfaces that should be enabled to implement an effective integration of risk management activities within the Agency. Part 2 provides self-contained, end-to-end examples of application of the processes and techniques introduced in Part 1, in the context of both programmatic (i.e., project and/or mission related) and institutional activities.

Risk Leadership↗
DOE OSTI2012

Measured Impact on Space Conditioning Energy Use in a Residence Due to Operating a Heat Pump Water Heater inside the Conditioned Space

The impact on space conditioning energy use due to operating a heat pump water heater (HPWH) inside the conditioned space is analyzed based on 2010-2011 data from a research house with simulated occupancy and hot water use controls. The 2700 ft2 (345 m2) house is located in Oak Ridge, TN (mixed-humid climate) and is equipped with a 50 gallon (189 l) HPWH that provided approximately 55 gallons/d (208 l/d) of hot water at 120 F (46 C) to the house during the test period. The HPWH has been operated every other week from December 2010 through November 2011 in two modes; a heat pump only mode, and a standard mode that utilizes 15355 Btu/hr (4500 W) resistance heating elements. The energy consumption of the air-source heat pump (ASHP) that provides space conditioning for the house is compared for the two HPWH operating modes with weather effects taken into account. Impacts during the heating and cooling seasons are compared.

heat pump water heater↗
DOE OSTI2013

Irradiation of SiC Clad Fuel Rods in the HFIR

During 2009 and- 2010, new test capability for the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) was developed that allows testing of advanced nuclear fuels and cladding under prototypic light-water-reactor (LWR) operating conditions (i.e., cladding and fuel temperatures, fuel average linear heat generation rates, and cladding fluence). For the initial experiments for this test program, ORNL teamed with commercial fuel/cladding vendors who have developed an advanced composite-wound SiC cladding material for possible use in LWRs. The first experiment, containing SiC-clad UN fuel, was inserted in HFIR in June 2010, and the second experiment, containing SiC-clad UO2 fuel, was inserted in October 2010. Two capsules (one containing UN fuel and the other UO2) were withdrawn from their respective assemblies in November 2011 at an estimated fuel burnup of approximately 10 GWd/MTHM; and two capsules (one containing UN fuel and the other UO2) were withdrawn from their respective assemblies in February 2013 at an estimated fuel burnup of approximately 20 GWd/MTHM. These capsules are currently awaiting PIE. This paper will describe the experiment, as-run operating conditions for these capsules, and current PIE plans and status.

Irradiation SiC fuel rods HFIR↗
DOE OSTI2014

First Look at Smoke Emissions from Prescribed Burns in Long-unburned Longleaf Pine Forests

While fire has long played a role in the longleaf pine ecosystem, there are still some stands in the southeastern United States where fire has not been reintroduced and fuels have accumulated for 50 years or more. As part of a larger study examining fuel loading and smoke emissions on Department of Defense installations in the southeastern U.S., fuels and trace emissions were measured during three prescribed burns at Ft. Jackson Army Base near Columbia, South Carolina in November 2011. These pine-forest understory fires provided valuable emissions data for fires that burned in stands that had little or no exposure to fire for decades. Smoke emissions were measured on the ground and from an aircraft by scientists from a large team of atmospheric researchers. (Akagi et al., 2013) To characterize initial emissions in the lofted plume and in point sources of residual smoldering combustion, trace-gas species were measured using an airborne FTIR and a ground-based FTIR, respectively. Whole-air sampling canisters were also collected from both ground- and airborne-based platforms. A total of 97 trace gases were quantified in this work, largely via infrared spectroscopy. Selected emissions data were compared with similar data collected from prescribed burns sampled in coastal North Carolina in 2010 in younger fuels beds of loblolly/longleaf stands near Camp Lejeune (Burling et al., 2011). The emission factors measured in this work differ by ~13-195% to EF measured from the managed stands at Camp Lejeune for organic and N-containing species, suggesting that fire emissions in similar ecosystems can exhibit large variability. Part of the differences, however, may be ascribed to burn conditions as well since the NC burns were during the wet season whereas the SC stands were burned after an extended drought. We also report the first detailed FTIR emissions data for a suite of monoterpenes. Figure 1 displays the emission factors (g/kg fuel) for several monoterpenes and isoprene as measured by the ground-based FTIR system. Due to their unsaturated structure, terpenes are highly reactive compounds emitted from plants thought to contribute to secondary organic aerosol formation (SOA) (Saathoff et al., 2009; Hennigan et al., 2011) and the formation of small oxygenated volatile organic compounds (OVOCs) (Jacob et al., 2002) in fire plumes. The known chemistry and measured abundance of monoterpenes suggests that these species impacted secondary plume processes including ozone, OVOC, and SOA formation in sampled plumes within the first few hours after emission.

biomass burning↗
DOE OSTI2013

How Stakeholder Engagement is Evolving at the Caldas Uranium Mining Site in Minas Gerais, Brazil - 13223

The Caldas site is located in the Federal State of Minas Gerais in Brazil about 25 km from the city of Pocos de Caldas. While the city itself has 150,000 inhabitants there is a total population of around 0.5 million people living in an area that could potentially be influenced by the site. Uranium ore was mined and milled here between the years of 1982 and 1995, with ore extraction taking place from an open pit. Of the material removed, aside from that extracted for uranium, some was used on-site for road construction and building embankments while the remainder was disposed of onto two major rock piles. There are a number of potential historical and current environmental impacts to groundwater as a consequence of discharges into streams which then flow off site. The site is now undergoing a phase of decommissioning which includes the formulation and substantiation of a site remediation strategy. As part of a wider International Atomic Energy Agency (IAEA) Technical Cooperation Project aimed at providing practical guidance for implementing a decommissioning and remediation plan at the site, WSP E and E were invited to lead a mission in order to provide advice on the importance and merits of stakeholder engagement and how to ultimately build an engagement program. In November 2011, WSP E and E met with personnel from the site operators, the Brazilian regulatory bodies and representatives from the local stakeholder community and explained the principles of stakeholder engagement and how the process had internationally evolved principally from a decide-announce-defend approach to a more formal two way mechanism of engagement. Historically there had been insufficient liaison between the site operator, the nuclear regulator and the environmental regulator. All parties had recognized that greater interaction was necessary. There had also been very little engagement with local stakeholders about the various activities on the site and the potential implications of these activities on human health and the environment. The main concerns of the local stakeholders were in relation to potential environmental impacts on groundwater and surface water as well as their lack of knowledge about the site's activities and how it might evolve over time. There was a feeling that the site brought no real benefit to the local community as local labor was rarely utilized when work was being undertaken. WSP E and E were asked many questions about stakeholder engagement processes and had to address a number of concerns relating to being able to construct and control an engagement program. Advice was provided on how to construct a phased program in a manner that would allow the site operator to demonstrate increased transparency and allow as wide a range of stakeholders as possible the opportunity to become engaged. We provided an important message in that engagement often had to be culture and project specific and that what might work in one country could not necessarily purely be transposed to another. Since the WSP E and E mission there has been evidence of a number of positive steps in many of the areas of stakeholder engagement related to the Caldas site. The nuclear and environmental regulators work in a more open and transparent manner and continue to undertake joint inspections of the Caldas site. They have agreed to develop a written agreement that will enable them to jointly assess and discuss the issues on the site. Both regulatory bodies had previously accompanied the site operator on a visit to the Wismut uranium mining area in Germany and as well as providing useful learning had also allowed the regulators to discuss some common issues, thus bringing them closer together. A local stakeholder group under the auspices of the Water Commission had previously been set up but now they are starting to have more regular meetings with the site operator and nuclear regulator. They are now additionally considering the formation of a site specific advisory board (based on similar lines to those at US legacy sites) in order to gain some further technical focus within the stakeholder community. The site operator has started to present and explain the proposed environmental remediation plans to various towns and cities potentially influenced by the Caldas site. The successes to date can be attributed primarily to the willingness of the site operator to engage more openly with local community representatives in addition to the enthusiasm of the Water Commission itself. Providing stakeholder engagement advice to all the relevant parties in a manner which recognized their concerns, aspirations and country specific culture was extremely important for this positive progress to have been established. The process established and the subsequent successes could provide useful learning to those countries that face similar cultural engagement challenges. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2013

Studies, Transport and Treatment Concept for Boilers from Berkeley NPP, England - 13599

In November 2011 Studsvik was awarded a contract to transport five decommissioned boilers from the Berkeley Nuclear Licensed Site in the UK to the Studsvik Nuclear Site in Sweden for metal treatment and recycling. A key objective of the project was to remove the boilers from the site by 31 March 2012 and this was successfully achieved with all boilers off site by 22 March and delivered to Studsvik on 6 April. Four boilers have been processed and the fifth is planned for completion by end of December 2012.The project had many challenges including a very tight timescale and has been successfully delivered to cost and ahead of the baseline programme. This paper describes the project and the experience gained from treatment of the first four boilers. It is the first UK project to send large components overseas for recycling and provides new insight into the processing of Magnox gas-circuit components. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2012

Decommissioning and Demolition of a Redundant UK Research Facility at AWE Aldermaston - 12453

The redundant two-storey brick built research facility on the AWE Site at Aldermaston, UK is in the closing stages of decommissioning and demolition. The facility was used for a variety of purposes up to 1995 predominately involving the use of alpha-emitting isotopes. The two main areas of alpha-based contamination have been decommissioned with the removal of hot -boxes and fume cupboards on the ground floor and HEPA filter units and ventilation equipment on the first floor. Many of these activities were undertaken using both airline fed suits, (supplied via a free standing mobile unit), and full face respirators. Asbestos materials were located and cleared from the first floor by specialist contractor. All sections of active drain running from the building to the site active effluent disposal system were removed early in the program using established techniques with specialist monitoring equipment used to provide confidence in the data required for disposal of the decommissioning debris. In particular a dedicated High Resolution Gamma Spectrometer (radioactive materials scanning unit) was utilized to categorise waste drums and wrapped packages. The building has been decommissioned and the monitoring and sampling of the structure was completed in November 2011 - the results demonstrating that the building was clear of contamination in accordance with UK clearance and exemption requirements. The demolition plan was developed and implemented in December with site excavation of foundations and site clearance currently ongoing in preparation for final site backfill activities and project close. A number of useful lessons have been learnt during the operations and are set out at the rear of the main text. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2012

Salt Disposal Investigations to Study Thermally Hot Radioactive Waste In A Deep Geologic Repository in Bedded Rock Salt - 12488

A research program is proposed to investigate the behavior of salt when subjected to thermal loads like those that would be present in a high-level waste repository. This research would build upon results of decades of previous salt repository program efforts in the US and Germany and the successful licensing and operation of a repository in salt for disposal of defense transuranic waste. The proposal includes a combination of laboratory-scale investigations, numerical simulations conducted to develop validated models that could be used for future repository design and safety case development, and a thermal field test in an underground salt formation with a configuration that replicates a small portion of a conceptual repository design. Laboratory tests are proposed to measure salt and brine properties across and beyond the range of possible repository conditions. Coupled numerical models will seek to describe phenomenology (thermal, mechanical, and hydrological) observed in the laboratory tests. Finally, the field test will investigate many phenomena that have been variously cited as potential issues for disposal of thermally hot waste in salt, including buoyancy effects and migration of pre-existing trapped brine up the thermal gradient (including vapor phase migration). These studies are proposed to be coordinated and managed by the Carlsbad Field Office of DOE, which is also responsible for the operation of the Waste Isolation Pilot Plant (WIPP) within the Office of Environmental Management. The field test portion of the proposed research would be conducted in experimental areas of the WIPP underground, far from disposal operations. It is believed that such tests may be accomplished using the existing infrastructure of the WIPP repository at a lower cost than if such research were conducted at a commercial salt mine at another location. The phased field test is proposed to be performed over almost a decade, including instrumentation development, several years of measurements during heating and then subsequent cooling periods, and the eventual forensic mining back of the test bed to determine the multi-year behavior of the simulated waste/rock environment. Funding possibilities are described, and prospects for near term start-up are discussed. Mining of the access drifts required to create the test area in the WIPP underground began in November 2011. Because this mining uses existing WIPP infrastructure and labor, it is estimated to take about two years to complete the access drifts. WIPP disposal operations and facility maintenance activities will take priority over the SDI field test area mining. Funding of the SDI proposal was still being considered by DOE's Offices of Environmental Management and Nuclear Energy at the time this paper was written, so no specific estimates of the progress in 2012 have been included. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Managing Low-Level Waste at Dounreay - 16269

Dounreay Site Restoration Limited (DSRL) is the site licence company responsible for the clean-up and demolition of Britain's former centre of fast reactor research and development. The Dounreay site requires facilities to dispose of up to 175,000 cubic metres of low level waste (LLW) that has been and will continue to be generated during the decommissioning and restoration of the site. In May 2014, construction of two new vaults for the disposal of LLW at Dounreay was completed, including the necessary roads, infrastructures and services, followed by an encapsulation plant in September 2014. The vaults are located immediately to the northeast of the Dounreay licensed site, on NDA-owned land. The facilities are for disposal of the solid LLW generated at Dounreay and the adjacent Vulcan site only. In 2004, following consultation with stakeholders and members of the public, Dounreay issued the 'Best Practicable Environmental Option (BPEO) Report' on the management of Dounreay LLW. This report assessed potential management options for LLW against a range of criteria, including technical, environmental, cost, health and safety issues. The study was conducted in line with best practice and involved consultation with a range of people, including the local community and organisations with an interest in radioactive waste management. The recommendations and conclusions from the study provided the basis for the 'Dounreay Solid LLW Overall Strategy', which was published in March 2005. A fundamental component of this strategy was the development of new below-ground disposal vaults for LLW at Dounreay. Siting the vaults on land at Dounreay avoids any need to transport the LLW away from Dounreay on public roads. Disposal at Dounreay therefore satisfies the proximity principle of managing the waste at source. Disposal at Dounreay is also consistent with UK Government Policy on LLW management, the Scottish Government's Radioactive Waste Management Policy and the Nuclear Decommissioning Authority's (NDA's) strategy on management of LLW from the UK nuclear industry. A planning application was initially lodged with the Highland Council in June 2006. The period for the determination of this application was extended to allow the Scottish Environment Protection Agency (SEPA) sufficient time to assess fully the supporting Environmental Safety Case (ESC). The planning application was re-activated in May 2008, and planning permission was granted by Highland Council in April 2009. The planning permission included 26 conditions on DSRL, covering a wide range of environmental issues such as construction noise/dust, traffic, visual impact and also a condition to develop a community fund aimed at socio-economic development of the area around the Dounreay site. After undertaking the necessary detailed design work, construction of the phase one vaults commenced in November 2011 by principal contractor, Graham Construction. Work was undertaken on both vaults simultaneously, excavating around 243,000 m{sup 3} of rock. When excavation was complete, steel reinforcement was placed and concrete poured to construct the floor slabs. This was followed by the construction of the reinforced walls and then the installation of the steel support structure and materials that form the roof. Mechanical and electrical installation then followed, in parallel with the construction of the vault apron, ramps and access roads. A pumping system and control building was also constructed to remove groundwater from around the vaults to allow the vaults to be kept dry while they are being filled with waste. A layer of excavated material, approximately 3 m thick, was placed across the existing ground surface between the vaults and the coast, to ensure the water table lies well below the new ground surface after closure of the vaults, and that any future trace contaminated groundwater flows out to the sea rather than to the soil zone. This layer is referred to in project documents as the 'enhanced geosphere'. After disposals are completed and the vaults are closed, this layer will be joined to the capping over the vaults so that the ensemble merges visually with the surrounding landscape. The original vegetation and soil mix will be returned as far as is practicable. An encapsulation plant has been constructed to fill the LLW containers with grout prior to disposal in the vault, similar to the process used at the national Low-Level Waste Repository facility (LLWR), near Drigg in Cumbria. The plant has the capacity to grout up to four containers per day. The grout fills voids in the container and helps provide chemical conditions in the vault that limit the release of radionuclides in the far future, after the vault has been penetrated by groundwater. On April 24 2015, active commissioning began at the Encapsulation Plant and LLW Vaults. Half-height ISO containers packed with low level waste are currently being filled with grout and disposed of in the LLW Vault. Also packaged Demolition Low Level Waste (DLLW) is being processed and disposed of in the Demolition Low Level Waste Vault. To date over 2500 packages of DLLW and 70 containers LLW have been disposed of. Completion of construction and the start of operating the Phase One vaults and encapsulation plant are fundamental to the successful and efficient decommissioning of the Dounreay site, upon which many millions of pounds of investment and hundreds of jobs rely.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Overall Reactor System Description of Prototype Gen-IV Sodium Cooled Fast Reactor

A fast reactor system has been recognized as one of the most promising options for transmutation of the radioactive wastes discharged from spent nuclear fuel of light water reactors (LWRs). That is owing to the intrinsic features of a fast reactor, i.e., high neutron energy and abundant excessive neutrons in the core. In this context, the Korea Atomic Energy Commission (KAEC) authorized the R and D action plan for the advanced sodium cooled fast reactor (SFR) connected with the pyro-process to provide a consistent direction to long-term R and D activities in December 2008. The long term plan was updated in November 2011 in order to refine the plan and to consider the available budget for SFR. The revised milestones include the completion of a specific design of a prototype Gen IV sodium cooled fast reactor (PGSFR) by 2017, specific design approval by 2020, and construction by 2028. The R and D activities on SFR had been concentrated on the basic and strategic key technology developments before 2012 and went to engineering project for licensing and construction of PGSFR from 2012. The development of PGSFR is now in the first design phase and will go toward to the second design phase in 2016. All the high level design concepts of systems, structures and components (SSCs) are determined and incorporated into the preliminary safety information document (PSID), which includes basic design requirements and descriptions and the results of safety analysis for the representative accident scenarios. The PSID will be a base material for a pre-review of the PGSFR safety. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2012

Lessons learned from the Siting Process of an Interim Storage Facility in Spain - 12024

On 29 December 2009, the Spanish government launched a site selection process to host a centralised interim storage facility for spent fuel and high-level radioactive waste. It was an unprecedented call for voluntarism among Spanish municipalities to site a controversial facility. Two nuclear municipalities, amongst a total of thirteen municipalities from five different regions, presented their candidatures to host the facility in their territories. For two years the government did not make a decision. Only in November 30, 2011, the new government elected on 20 November 2011 officially selected a non-nuclear municipality, Villar de Canas, for hosting this facility. This paper focuses on analysing the factors facilitating and hindering the siting of controversial facilities, in particular the interim storage facility in Spain. It demonstrates that involving all stakeholders in the decision-making process should not be underestimated. In the case of Spain, all regional governments where there were candidate municipalities willing to host the centralised interim storage facility, publicly opposed to the siting of the facility. (author)

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

Effect of Alkali-Silica Reaction on Shear Strength of Reinforced Concrete Structural Members

Alkali-silica reaction (ASR) was discovered in the early 40s by Stanton (1940) of the California Division of Highways. Since, it has been recognized as a major degradation mechanism for concrete dams and transportation infrastructures. Sometimes described as the ’cancer of concrete’, this internal swelling mechanism causes expansion, cracking and loss of mechanical properties. There are no known economically viable solutions applicable to massive concrete to prevent the reaction once initiated. The e ciency of the mitigation strategies for ASR subjected structures is limited. Several cases of ASR in nuclear generating stations have been disclosed in Japan (Takatura et al. 2005), Canada at Gentilly 2 NPP (Tcherner and Aziz 2009) 1, and more recently, in the United States for which the U.S. Nuclear Regulatory Commission issued Information Notice (IN) 2011-20, ’Concrete Degradation by Alkali Silica Reaction,’ on November 18, 2011, to provide the industry with information related to the ASR identified at Seabrook. Considering that US commercial reactors in operation enter the age when ASR degradation can be visually detected and that numerous non nuclear infrastructures (transportation, energy production) have already experienced ASR in a large majority of the States (e.g., Department of Transportation survey reported by Touma (Touma 2000)), the susceptibility and significance of ASR for nuclear concrete structures must be addressed in the perspective of license renewal and long-term operation beyond 60 years. The aim of this report is to perform an extensive parametric series of 3D nonlinear finite element analyses of three di erent “beam-like” geometries, including two di erent depths, three di erent types of boundary conditions, and four other parameters: namely, the ASR volumetric expansion, the reinforcement ratio, the loss of elastic modulus induced by ASR and the loss of tensile strength caused by ASR.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2012

Upgrade and Certification of the Los Alamos National Laboratory SHENC 2011 - 12270

Nondestructive assay measurements of Transuranic (TRU) waste at Los Alamos National Laboratory (LANL) required the addition of a standard waste box (SWB) assay system. A Super High Efficiency Neutron Counter (SHENC) located at Hanford was identified to be relocated to LANL. After careful evaluation of waste streams at LANL, it was determined that the current configuration of the SHENC was not sufficient to quantify certain waste streams. At LANL, there is still a large amount of waste that needs to be retrieved and repackaged within SWB's to meet agreements with the State of New Mexico. Prior to relocating the SHENC, the only assay systems available were High Efficiency Neutron Counters having only a 55-gallon drum capacity. Further analyses indicated that the SHENC system should be capable of quantitative gamma measurements that are to be linked, and combined, with the neutron measurements. The SHENC system was therefore augmented with a new high-resolution gamma spectroscopy system using BE5030 detectors and upgraded gamma electronics. The neutron side of the system was also upgraded with an advanced shift register (JSR-15), an improved Programmable Logic Controller and NDA-2000 software. This report will include calibration of both the neutron and gamma modalities of the SHENC system and how the modality results are combined to produce a single assay result. Preliminary performance results will be discussed based on both mock and real waste measurements. Discussions will also include a complete description of the adjustable parameters as well as the calibration plan, techniques and validations including calibration confirmation based on the Waste Isolation Pilot Plant Waste Acceptance Criteria (WIPP-WAC). The SHENC was successfully upgraded to efficiently measure the complex waste streams at Los Alamos National Laboratory. A new PLC was successfully added to the system for Add-A-Source control. A new shift register was added to the SHENC (JSR-15) which provides more flexibility if replacement is required. The addition of the density based calibration on the gamma modality of the system increases the effectiveness of the SHENC for high alpha-n producing waste. Upgrading the system to new software also helped to standardize the program at Los Alamos. Only one new procedure was initiated for the integration of the SHENC. Add-A-Source measurements were effectively integrated with the system based on the confirmation results and positive results during two Department of Energy Performance Demonstration Program Box Cycles. Total measurement uncertainty estimates were completed for both the gamma modality and the neutron modality of the system. The SHENC was reviewed by both the Department of Energy and the Environmental Protection Agency in 2011. The certification letter for the SHENC was issued on November 16, 2011. With the certification letter issued to the Central Characterization Project the SHENC can perform waste measurements on SWB's at Los Alamos for shipment to WIPP. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2012

Entry, Descent, and Landing Communications for the 2011 Mars Science Laboratory

The Mars Science Laboratory (MSL), established as the most advanced rover to land on the surface of Mars to date, launched on November 26th, 2011 and arrived to the Martian Gale Crater during the night of August 5th, 2012 (PDT). MSL will investigate whether the landing region was ever suitable to support carbon-based life, and examine rocks, soil, and the atmosphere with a sophisticated suite of tools. This paper addresses the flight system requirement by which the vehicle transmitted indications of the following events using both X-band tones and UHF telemetry to allow identification of probable root causes should a mission anomaly have occurred: Heat-Rejection System (HRS) venting, completion of the cruise stage separation, turn to entry attitude, atmospheric deceleration, bank angle reversal commanded, parachute deployment, heatshield separation, radar ground acquisition, powered descent initiation, rover separation from the descent stage, and rover release. During Entry, Descent, and Landing (EDL), the flight system transmitted a UHF telemetry stream adequate to determine the state of the spacecraft (including the presence of faults) at 8 kbps initiating from cruise stage separation through at least one minute after positive indication of rover release on the surface of Mars. The flight system also transmitted X-band semaphore tones from Entry to Landing plus one minute although since MSL was occulted, as predicted, by Mars as seen from the Earth, Direct-To-Earth (DTE) communications were interrupted at approximately is approx. 5 min after Entry ( approximately 130 prior to Landing). The primary data return paths were through the Deep Space Network (DSN) for DTE and the existing Mars network of orbiting assets for UHF, which included the Mars Reconnaissance Orbiter (MRO), Mars Odyssey (ODY), and Mars Express (MEX) elements. These orbiters recorded the telemetry data stream and returned it back to Earth via the DSN. The paper also discusses the total power received during EDL and the robustness of the telecom design strategy used to ensure EDL communications coverage.

relay operations↗
DOE OSTI2014

Heavy Quark and Neutrino Physics. Final report, 2011-2-14

This final closeout report covers research supported by the ''Heavy Quark and Neutrino Physics'' grant at Kansas State University during the grant's last renewal period, November 1, 2011, through April 30, 2014. The report begins with an overview of the group, its goals and activities, and personnel. Then summaries are given of achievements in each of the three frontiers: Energy Frontier research in the D0 and CMS experiments; Intensity Frontier research in the Double Chooz and ArgoNeuT experiments as well as research and development for MicroBooNE and LBNE; and Cosmic Frontier and Theoretical research. The report concludes with a list of publications supported by this grant in which our group made a significant contribution during the reporting period, followed by a list of students partially or fully supported by the grant who were awarded a PhD during this period.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2012

NEAMS Update: Quarterly Report for October - December 2011

The Advanced Modeling and Simulation Office within the DOE Office of Nuclear Energy (NE) has been charged with revolutionizing the design tools used to build nuclear power plants during the next 10 years. To accomplish this, the DOE has brought together the national laboratories, U.S. universities, and the nuclear energy industry to establish the Nuclear Energy Advanced Modeling and Simulation (NEAMS) Program. The mission of NEAMS is to modernize computer modeling of nuclear energy systems and improve the fidelity and validity of modeling results using contemporary software environments and high-performance computers. NEAMS will create a set of engineering-level codes aimed at designing and analyzing the performance and safety of nuclear power plants and reactor fuels. The truly predictive nature of these codes will be achieved by modeling the governing phenomena at the spatial and temporal scales that dominate the behavior. These codes will be executed within a simulation environment that orchestrates code integration with respect to spatial meshing, computational resources, and execution to give the user a common 'look and feel' for setting up problems and displaying results. NEAMS is building upon a suite of existing simulation tools, including those developed by the federal Scientific Discovery through Advanced Computing and Advanced Simulation and Computing programs. NEAMS also draws upon existing simulation tools for materials and nuclear systems, although many of these are limited in terms of scale, applicability, and portability (their ability to be integrated into contemporary software and hardware architectures). NEAMS investments have directly and indirectly supported additional NE research and development programs, including those devoted to waste repositories, safeguarded separations systems, and long-term storage of used nuclear fuel. NEAMS is organized into two broad efforts, each comprising four elements. The quarterly highlights October-December 2011 are: (1) Version 1.0 of AMP, the fuel assembly performance code, was tested on the JAGUAR supercomputer and released on November 1, 2011, a detailed discussion of this new simulation tool is given; (2) A coolant sub-channel model and a preliminary UO{sub 2} smeared-cracking model were implemented in BISON, the single-pin fuel code, more information on how these models were developed and benchmarked is given; (3) The Object Kinetic Monte Carlo model was implemented to account for nucleation events in meso-scale simulations and a discussion of the significance of this advance is given; (4) The SHARP neutronics module, PROTEUS, was expanded to be applicable to all types of reactors, and a discussion of the importance of PROTEUS is given; (5) A plan has been finalized for integrating the high-fidelity, three-dimensional reactor code SHARP with both the systems-level code RELAP7 and the fuel assembly code AMP. This is a new initiative; (6) Work began to evaluate the applicability of AMP to the problem of dry storage of used fuel and to define a relevant problem to test the applicability; (7) A code to obtain phonon spectra from the force-constant matrix for a crystalline lattice has been completed. This important bridge between subcontinuum and continuum phenomena is discussed; (8) Benchmarking was begun on the meso-scale, finite-element fuels code MARMOT to validate its new variable splitting algorithm; (9) A very computationally demanding simulation of diffusion-driven nucleation of new microstructural features has been completed. An explanation of the difficulty of this simulation is given; (10) Experiments were conducted with deformed steel to validate a crystal plasticity finite-element code for bodycentered cubic iron; (11) The Capability Transfer Roadmap was completed and published as an internal laboratory technical report; (12) The AMP fuel assembly code input generator was integrated into the NEAMS Integrated Computational Environment (NiCE). More details on the planned NEAMS computing environment is given; and (13) The NEAMS program website (neams.energy.gov) is nearly ready to launch.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗