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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Considerations and Lessons Learned from the Use of Gamma Spectroscopy Systems at FUSRAP Project Sites - 17459

This paper will discuss the application of gamma spectroscopy systems for analysis of environmental media samples for parents and daughter progeny of the Natural Uranium and Thorium Decay Series radionuclides. The concentrations and relative ratios of naturally occurring isotopes are used to confirm the presence of FUSRAP-related wastes and for understanding the associated potential dose and health risks. Focus will be given to lessons learned from the set-up and operation of onsite gamma spectroscopy laboratories used to provide stakeholders with defensible and timely results to support FUSRAP site investigations and remediation including adaptive survey design implementation, physical remediation and waste transport, and confirmatory final status survey activities. This paper focuses on the potential impacts to gamma spectroscopy measurement accuracy from the following: - Bias caused by sample matrix effects as well as use of different library reference values between performance evaluation study providers and testing laboratories; - Use of calibration sources with limited energy ranges, and; - Selection of available alternative isotopic decay reference data for the input of line energies and their intensities. These lessons learned include discussing how inter-laboratory measurement differences from blind performance evaluation samples are affected by the manufacturer's measurement method, including equilibrium assumptions; the isotope decay information source library used by the study provider and participating laboratories; and calibration source geometry/density variances from actual sample conditions. Any of these factors can significantly impact the accuracy of reported results data. Deepening the reader's understanding of the various factors that impact the accuracy, interpretation, and overall usability of gamma spectroscopy results data from laboratories will help ensure defensible decision-making and cost-effective mission implementation within FUSRAP and similar remediation programs. (authors)

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

French Atomic and alternative energies commission decommissioning policy and strategies: What is at stake lessons learned and feedback experience - 15013

Since its creation in 1945, the French Atomic Energy and Alternative Energies Commission has carried out research programmes on civil use of nuclear, and its application. CEA has set up and run various types of installations from research (accelerators, pond reactors, fast reactors, laboratories) to industry (power reactor, processing facilities). There are currently more than several tens of facilities which are presently closed down pending dismantling or in the process of being dismantled by CEA, the governmental body for research and development in nuclear and renewable energies. When operating, all these installations have generated radioactive waste. When they are shutdown, either as a result of the programmes for which they were set up, or due to equipment wearing out or being obsolete, these installations must be cleaned up, dismantled and decommissioned, taking into account their nuclear nature and requirements related to safety and environment. During the decommissioning process, the implementer has to deal with safety and site remediation issues. Dealing with these installations is a long-term programme which must be carefully planned and financed in order to optimise its management. The paper will describe the CEA's decommissioning policy, strategies adopted, and draw up lessons learned and feedback experience, showing that: - Safety is guaranteed, - Dismantling is a technically controllable operation, but R and D actions are to be developed for specific problems as characterization or operation in hostile environment. Moreover all the methods and techniques improve as a result of feedback experience, - The amount of material and waste produced by the dismantling are manageable. The very low, low and intermediate level waste can be stored on existing shallow land burial centres, some new repositories have to be created for specific waste (graphite, radium,...) and for high and intermediate level long live waste, which are stored in interim storage , - The dismantling must be optimized, especially by appliance of a good strategy based on rational industrial choices. - Communication and transparency with stakeholders is essential for global process acceptance, - The lessons learned and how feedback experience could benefit for future decommissioning projects. (authors)

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

Salt Waste Processing Facility project lessons learned: Acquisition through construction - 15518

The Salt Waste Processing Facility (SWPF), located at the Savannah River Site (SRS) in Aiken, South Carolina, is a multi-billion dollar Liquid Radioactive Waste (LRW) processing facility that represents the keystone for the U.S. Department of Energy (DOE)-EM clean-up mission at SRS. The SWPF facilitates DOE-EM clean-up at SRS by decontaminating the salt waste, which is the dominant volumetric component in the LRW tanks, thereby allowing the cleaned salt waste to be removed from the tanks and stabilized into an approved grout-based final waste form. The small volume of removed radionuclides is sent to the Defense Waste Processing Facility (DWPF) for vitrification. Emptied LRW storage tanks are then grouted into an approved configuration for final closure. The SWPF project is currently 100% complete with design, 80% complete with construction, and 10% complete with commissioning. To date there have been numerous lessons learned with regard to project acquisition, design, procurement, construction, and quality assurance (QA) approaches (both good practices and mistakes) that are considered to be of significant value in improving the state of major project execution within the DOE-EM clean-up program as well as to the wider DOE enterprise. An overview of the current SWPF project status is provided and key lessons learned in the aforementioned areas are presented relative to improving future DOE major project execution performance. Specific areas to be addressed include strategies to optimize integration of design and nuclear safety, constructability tools for design and construction synchronization, commercial grade dedication (CGD) approaches to mitigate atrophy in the nuclear supply chain, and QA perspectives to facilitate effective and efficient project execution. (authors)

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

Lessons Learned from FUSRAP - 16200

The US DOE Office of Legacy Management (LM) is the long-term steward for 90 sites remediated under numerous regulatory regimes including the Formerly Utilized Sites Remedial Action Program (FUSRAP) sites. In addition, LM holds considerable historical information, gathered in the 1970's, to determine site eligibility for remediation under FUSRAP. To date, 29 FUSRAP sites are in LM's inventory of sites for long-term surveillance and maintenance (LTS and M), and 25 are with the US Army Corps of Engineers (USACE) for remediation or in the process of being transitioned to LM. It is forecasted that 13 FUSRAP sites will transfer from the USACE to LM over the next 10 years; however, the timing of the transfers is strongly dependent upon federal funding of the ongoing remedial actions. Historically, FUSRAP sites were generally cleaned up for unrestricted industrial use or remediated to the cleanup standards at that time, and their use remained unchanged. Today, these sites as well as the adjacent properties are now changing or envisioned to have changes in land use, typically from industrial to commercial or residential uses. The implication of land-use change affects DOE's LTS and M responsibility for the sites under LM stewardship as well as the planning for the additional sites scheduled to transition in time. Coinciding with land-use changes at or near FUSRAP sites is an increased community awareness of these sites. As property development increases near FUSRAP sites, the general public and interested stakeholders regularly inquire about the sufficiency of cleanups that impact their neighborhoods and communities. LM has used this experience to address a series of lessons learned to improve our program management in light of the changing conditions of our sites. We describe these lessons learned as (1) improved stakeholder relations, (2) enhanced LTS and M requirements for the sites, and (3) greater involvement in the transition process. (authors)

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

Daher-TLI UCSC Wash Process - Lessons Learned from Handling a Legacy Cylinder - 16506

The Daher-TLI UF{sub 6} Cylinder Service Center (UCSC) began operation in 2013 and functions as a dedicated wash, re-certification, storage and disposal facility for 122 cm uranium hexafluoride (UF{sub 6}) cylinders. The primary purpose of the facility is to provide cylinder cleaning and re--certification services to the UF{sub 6} industry for cylinders that previously contained natural or depleted UF6. The facility also has the ability to recover most of the uranium in the form of uranyl peroxide (UO{sub 4}) or triuranium octoxide (U{sub 3}O{sub 8}). Small residues of UF{sub 6} (commonly referred to as a heel) from natural cylinders are removed and treated in a patented three-step purification process that recovers U{sub 3}O{sub 8} that meets the ASTM specification. The wastewater ordinarily contains a mixture of sodium salts (77% sodium sulfate, 23% sodium nitrate) along with minute traces of uranium (1 - 2 mg/L) and fluoride (10 - 20 mg/L). Over a period of 6 months, lab analyses were performed on the filtrate from a legacy cylinder in an attempt to separate uranium and fluoride from this stream. These pilot results established near quantitative recovery of uranium (< 1 mg/L) and near complete separation of fluorides (5 - 15 mg/L). This paper follows the efforts of the Daher-TLI UCSC to process the abnormal heeled UF{sub 6} cylinder. This paper also documents the lessons learned from this experience and how those lessons were used to improve the UCSC wash process. These modifications served to recover 99.87% of the input uranium as UO{sub 4} while simultaneously creating a waste stream with only trace amounts of impurities. (authors)

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

Spent Nuclear Fuel Management and Disposal in Finland - Status and Lessons Learned at the End of 2015 - 16507

In November 2015 the Finnish Government approved and the Parliament ratified Posiva's 2012 License Application for Construction of a mined, deep geological repository for the spent nuclear fuel (SNF) at the Olkiluoto site in the Eurajoki municipality based upon recommendations provided by the Finnish Radiation Safety Authority (STUK), international expert groups and long-standing local support. The preceding siting process began in 1983 and it included disposal-concept selection (KBS-3V), 'consent-based' site selection and large-scale in-situ tests conducted in an underground research laboratory, the ONKALO, situated ∼440 m below the mean Sea level immediately adjacent to the planned repository at the Olkiluoto site. At the end of 2015, the Finnish SNF repository is projected to open in 2024 as the first of its kind. Four related lessons learned in Finland during the past 30 years are: 1. The selection of potentially-suitable sites for geological disposal of SNF proved to be more difficult and more time consuming than initially envisioned. 2. The siting of nuclear facilities has evolved from being mainly a radionuclide containment and isolation challenge to becoming a critical moving-target, socio-political challenge governing progress with majority local acceptance being a fundamental imperative. 3. Public and political acceptance and support are strongly linked to the competency, credibility and transparency of the involved organisations and the maturity/pedigree of the proposed disposal concept. 4. Timely sharing lessons learned and conducting selective collaborations with other countries proved to be successful keys to timely and cost-effectively obtain and maintain public and political acceptance and support. (authors)

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

Challenges, Successes, and Lessons Learned on Two Active DOE Facility D and D Projects - 18379

'Surgical removal', although having a number of technical and safety challenges, is an effective alternative to traditional Demolition and Decommissioning (D and D) methods. When carefully planned and managed, surgical removal of equipment can be safely performed to achieve cost savings and accelerated schedule. At Fernald, a large groundwater extraction system that treats radionuclides was downsized during continued operations. Challenges included demolition of remedial components in tight spaces adjacent to active components, in-situ management and removal of slurry multimedia and resins, and complex hoisting/rigging of whole vessels from very tight areas. The approach realized a significant reduction in waste volumes and slurry transfer to reduce radionuclide exposure while allowing use of existing vessels as IP-1 shipping containers while providing an opportunity to implement out of the box design for hoisting/rigging/moving large vessels. Several lessons were learned as Los Alamos Technical Associates, Inc. (LATA) faced the project challenges and progressed through the D and D process. The slurry removal required thorough understanding of equipment selection and circulation techniques to maintain a slurry while avoiding plugging of extraction equipment. The physical condition of each individual tank was different and required development of alternate removal techniques, such as draining the vessel and removal of the hard material with an air vacuum truck, for each one. Lessons learned regarding large tank removal focused on recertification of an overhead crane, determination of pick points from a partially filled vessel, reanalyzing the lifting lugs for a partially full tank, and requirements to fill all void space in the vessels to meet off-site disposal specifications. At Oak Ridge National Laboratory (ORNL), LATA performed the surgical removal of all biomass process equipment inside ORNL's Building 2719. Among the challenges was a requirement that the removal action had to be conducted during continued operations. Live steam lines, fire protection, water process and boiler feed water systems were operational during LATA's D and D effort and were in close proximity to removal operations. (authors)

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

Software Dependability for Digital Instrumentation and Control Systems in Nuclear Power Plants - Lessons Learnt from a DOE Sponsored Project

This paper discusses the lessons learnt from a sponsored study undertaken under the sponsorship of the Department of Energy by a team of scientists at the Ohio State University in collaboration with Technology Resources and experts around the world. This paper makes recommendations for future research and studies based on these lessons learnt. The purpose of the research was to provide a software dependability quantification framework that would allow its evaluation along the software development life cycle for safety critical instrumentation and control systems (I and C) such as those found in nuclear power plants. A typical example of safety critical system is the reactor protection system. The research funded by the Department of Energy built on preliminary research carried out for the US NRC that had focused solely on software reliability quantification. Quantification of software dependability is important for safety critical I and C because the regulatory framework in use in the United States for nuclear power plants is risk informed. Quantification of risk requires quantification of all contributors to risk and those include instrumentation and control systems. The purpose of the study was to help developers of software-based I and C with an early evaluation of the potential risk an application would represent at different stages of the software development life cycle by building gates at the end of each life cycle phase. Life cycle phases of software development comprehend phases such as requirements, design, coding and test. The gates' function would be to stop development from moving forward if the assessed dependability objective for that phase were not met. Gates thresholds were to be defined based on measurements collected during the life cycle phase under evaluation and phases that preceded it and an understanding of the mechanisms that would lead to threatening the dependability objectives. The information contained in the gates would in addition help steer the development towards areas that needed improvement. The following are four high level conclusions to our study. First the study demonstrates a lack of consensus on mechanisms that will threaten the dependability attributes. This lack of consensus should be resolved. The lack of consensus appears for all measures to the exception of reliability. Second, measures should be developed for software availability and safety. Third, for all dependability attributes (with the exception of reliability) consistency of the measurement threads should evaluated and measurement-based development gates derived. Finally our ability to perform such type of research depends in a significant manner on access to vendor and/or utility data. The licensing environment and the first-of-a-kind nature of current software-based applications for nuclear I and C make it difficult to collect the relevant data. An approach which would either increase access to data by providing 'immunity' to the vendor or utility or the development of a software-based I and C for the sole purpose of data collection for research should be investigated. (authors)

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

Lessons Learned from Most Recent Chemical Decontamination for Decommissioning Projects - 19280

In 2017, Westinghouse performed a full system chemical decontamination of Units 1 and 2 of the Bohunice V1 Nuclear Power Plant. Bohunice V1 is a VVER 440 design with six loops. The application was performed two loops at a time, with the reactor core bypassed. The Pressurizer and Pressurizer Relief Tank (Bubble Tank) were decontaminated as well, in a separate application. This was a recovery decontamination that had been attempted by another company prior to Westinghouse. Several modifications to equipment and design of process were required to make the decontamination successful. The project was initiated to perform pre-dismantling chemical decontamination of primary circuits of both V1 units using Decontamination for Decommissioning (DfD) to meet the following objectives (see References 1 and 2 for process descriptions of DfD): - Remove activity from the primary circuit components; - Reduce dose rates around piping and components; - Simplify access to the installations, making it possible to use hands-on techniques for dismantling, rather than the more expensive use of robotics or manipulators; - Minimize the potential for spreading contamination during decommissioning activities - Reduce the activity of components that they may be disposed of at a lower classification, therefore more economical, waste disposal category. Several techniques were employed that were unique, or first of a kind, to aid in the decontamination, including resin regeneration and bypass of the reactor core, while still providing enough flow to to allow sufficient dispersal through all the steam generator tubes. Equipment that was already available on site was evaluated and, when possible, combined with Westinghouse equipment to minimize application cost and schedule. The lessons learned from the first unit (Unit 2) were applied to the second unit (Unit 1) application. The partial relocation of equipment allowed for the most efficient schedule to complete the second decontamination. The paper will describe in more detail the results and lessons learned from the full system chemical decontaminations performed, as well as updates on another recent decontamination project. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

WIPP Operational and Safety Lessons Learned from the 2014 Fire and Radiological Events - 19389

The Waste Isolation Pilot Plant (WIPP) experienced two accident events in 2014 within 9 days of each other (salt haul truck fire and a radiological release). The repository was designed in the 1980's for high level waste and started operations in late 1990's for defense related transuranic (TRU) waste. Several long-standing technical issues from competing requirements between an underground facility (mine), nuclear safety, and environmental requirements lead to design, operations, and safety weaknesses that were not resolved prior to the two accident events. Other design issues and actions during early recovery efforts were identified as lessons learned for the Safety Significant Confinement Ventilation System (SSCVS) and Utility Shaft (US) capital asset projects and for future planning efforts. The infrastructure at WIPP was significantly degraded at the time of the events with key safety related items that had been out of service or not maintained for years. The emergency response to the two accident events was less than adequate and caused concerns with stakeholders. There are many operational and safety lessons learned from these two events and their corrective actions that will be valuable for all future planning of deep geological repositories (DGR). (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Panel Session 84: Challenges and Lessons Learned in Radioactive Waste Packaging, Transportation, and Disposal

This panel focused on challenges and lessons learned in radioactive waste packaging, transportation, compliance and disposal. Participants provided their perspectives and suggestions on how to increase efficiencies through eliminating inconsistencies between specifications and other requirements to provide products at a reasonable cost and enhance communication to enable better service. Presentations proposed include: 1 - Low Level Waste Type (B) Cask Shipment Challenges (Aleksandr Gelfond, EnergySolutions (USA)); 2 - Radioactive Packaging Challenges (Jeff England, NAC International (USA)); 3 - Challenges and Lessons Learned in Radwaste Packaging, Transportation, Compliance and Receipt (Mary Magleby, URS - CH2M Oak Ridge LLC (USA))

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Lessons Learned from More than Three Decades of Decommissioning and RAW Management in Slovakia - 20074

The purpose of this paper is to describe utilization of experience of JAVYS Company acquired while acting as the Slovak national decommissioning and radioactive waste management entity. JAVYS manages both the decommissioning of A1 NPP (shut down after series of accidents) and V1 NPP (shut down after standard operation) and related radioactive waste management. Besides JAVYS is responsible for management of institutional radioactive waste in Slovakia. The paper is focusing on selected successfully completed projects and related lessons learned from development of special procedures and implementation of activities within decommissioning and management of generated waste streams from cradle to grave. Recently, experience and lessons learned from all aforementioned activities are used internationally to provide assistance to other countries in order to overcome difficulties and to successfully implement various projects dealing with decommissioning and radioactive waste management. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Panel Session 79: Challenges and Lessons Learned in Radwaste Packaging, Transportation, Compliance, and Receipt

This panel focused on challenges and lessons learned in radioactive waste packaging, transportation, compliance, and receipt for fabricators of radioactive waste packaging. World-wide companies are urged to participate. Participants provided their perspectives and suggestions on how to increase efficiencies through eliminating inconsistencies between specifications and other requirements to provide products at a reasonable cost and enhance communication to enable better service. Panelists with presentations: PACTEC (Bill Smart); Waste Packaging Strategy and Challenges at Whiteshell (Miles Smith); Challenges and Lessons Learned in Radwaste Packaging, Transportation, Compliance and Receipt (Dan Payne)

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

Lessons learned from the commissioning of the THTR 300 - 18575

Although the commissioning of the THTR 300, the only large pebble bed High Temperature Gas-Cooled Reactor (HTGR) power plant, occurred more than 30 years ago, many lessons could be learned that would directly benefit the design, construction and startup of future pebble bed HTGRs. This report includes a review of the THTR 300 design and an overview of the commissioning program utilized to bring the plant from initial criticality to full power. Selected plant test results are compared to predicted plant behavior from 40% to 100% plant load. Lessons learned from the commissioning of the THTR are also included. (author)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2022

Challenges and Lessons Learned from an Analysis of Three Zero Energy Buildings

Zero energy buildings, or zero energy ready buildings, which are designed and operated by public or private commercial property owners can play an important role in reducing carbon emissions. This paper discusses lessons learned and key takeaways from an in-depth analysis of three zero energy buildings that took an integrated design and construction approach to significantly reduce energy use. Two of these projects are new construction and one is a retrofit to zero energy. Findings are based on project literature review, data analysis, and in-depth interviews with the building design teams and staff who were involved during the design, construction, and operation of the buildings. The paper addresses value proposition and cost data in such a way that other building owners can replicate the strategies and technology solutions in response to regulatory mandates or organizational goals. It also provides details on operational improvements taken at each zero energy building to enhance energy performance and increase the potential for load flexibility, and discusses challenges and lessons gleaned from design teams and building staff. The findings serve as a reference for building owners, designers, engineers, contractors, or others interested in, or involved with, the design, construction, or use of new or existing buildings. The paper also includes recommended pathways for widespread adoption of zero energy strategies that can be applied in various locations.

ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION↗
DOE OSTI2025

Risk Assessment in a Chemical Laboratory Following an Explosive Incident Involving a Novel Diazonium Compound: Retrospective Analysis and Lessons Learned

Diazonium compounds are synthetically useful in the production of dyes and textiles, however they are highly explosive under dry conditions. Explosion prevention becomes more difficult when new diazonium compounds are synthesized, because while some syntheses include a counterion to increase their stability, this is not always a reliable method to prevent an explosive incident. Due to the uncertainty surrounding the explosiveness of different diazonium compounds, it is important to understand how to safely clean up after an incident and how to determine when it is safe to return a laboratory to typical operational use, particularly when the incident involves a novel compound where a standard does not exist for instrument calibration. Here, an explosive event is discussed involving the synthesis of 4-bromo-benzenediazonium-2-carboxylate. Following the explosive incident and 3-step cleanup, which involved a precautionary neutralization step, samples were collected from the fume hood where the incident occurred. Because the incident involved an unstable, novel compound that is not commercially available and was deemed unsafe to resynthesize for instrument calibration, we assessed the risk of further explosion by analyzing for the stable decomposition products. Mass spectrometry analysis confirmed that the residue in the fume hood contained 5-bromosalicylic acid, a decomposition product of 4-bromo-benzenediazonium-2-carboxylate. Samples were taken from multiple points in the fume hood and analyzed to estimate the spatial distribution of the decomposition product. Based on this analysis, we inferred that the primary decomposition product was far more abundant than residual energetic, indicating the energetic had been consumed or neutralized to a trace quantity where the risk of further explosion was low. Furthermore, the steps presented here─specifically, initial neutralization and then analyzing the spatial distribution of expected decomposition products to assess risk when a novel explosive material is detonated in a confined space─were our approach to assess further risk following an explosion due to a novel diazonium compound without the need for any further handling or resynthesis of the energetic. Here, we present our approach and critically analyze these steps by discussing retrospective lessons learned and alternative analytical approaches.

Computer simulations↗
DOE OSTI2021

Lessons Learned From the Prototypes of the MQXFA Low-Beta Quadrupoles for HL-LHC and Status of Production in the US

With the successful test of the first two pre-series magnets the US HL-LHC Accelerator Upgrade Project has started production of the MQXFA magnets to be used in Q1/Q3 inner triplet elements of the HL-LHC. This good start comes after the test of two prototypes with limited performance, and it demonstrates the importance of learning from past issues. Therefore, in this paper we want to share the most important lessons learned so far, focusing on those which may be more interesting for similar projects. Additionally, we will present the status of MQXFA fabrication in the US.

43 PARTICLE ACCELERATORS↗