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DOE OSTI2013

Environmental impacts of residual Municipal Solid Waste incineration: A comparison of 110 French incinerators using a life cycle approach

Highlights: • 110 French incinerators are compared with LCA based on plant-specific data. • Environmental impacts vary as a function of plants energy recovery and NO{sub x} emissions. • E.g. climate change impact ranges from −58 to 408 kg CO{sub 2}-eq/tonne of residual MSW. • Implications for LCA of waste management in a decision-making process are detailed. - Abstract: Incineration is the main option for residual Municipal Solid Waste treatment in France. This study compares the environmental performances of 110 French incinerators (i.e. 85% of the total number of plants currently in activity in France) in a Life Cycle Assessment perspective, considering 5 non-toxic impact categories: climate change, photochemical oxidant formation, particulate matter formation, terrestrial acidification and marine eutrophication. Mean, median and lower/upper impact potentials are determined considering the incineration of 1 tonne of French residual Municipal Solid Waste. The results highlight the relatively large variability of the impact potentials as a function of the plant technical performances. In particular, the climate change impact potential of the incineration of 1 tonne of waste ranges from a benefit of −58 kg CO{sub 2}-eq to a relatively large burden of 408 kg CO{sub 2}-eq, with 294 kg CO{sub 2}-eq as the average impact. Two main plant-specific parameters drive the impact potentials regarding the 5 non-toxic impact categories under study: the energy recovery and delivery rate and the NO{sub x} process-specific emissions. The variability of the impact potentials as a function of incinerator characteristics therefore calls for the use of site-specific data when required by the LCA goal and scope definition phase, in particular when the study focuses on a specific incinerator or on a local waste management plan, and when these data are available.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2012

Modeling High-Impact Weather and Climate: Lessons From a Tropical Cyclone Perspective

Although the societal impact of a weather event increases with the rarity of the event, our current ability to assess extreme events and their impacts is limited by not only rarity but also by current model fidelity and a lack of understanding of the underlying physical processes. This challenge is driving fresh approaches to assess high-impact weather and climate. Recent lessons learned in modeling high-impact weather and climate are presented using the case of tropical cyclones as an illustrative example. Through examples using the Nested Regional Climate Model to dynamically downscale large-scale climate data the need to treat bias in the driving data is illustrated. Domain size, location, and resolution are also shown to be critical and should be guided by the need to: include relevant regional climate physical processes; resolve key impact parameters; and to accurately simulate the response to changes in external forcing. The notion of sufficient model resolution is introduced together with the added value in combining dynamical and statistical assessments to fill out the parent distribution of high-impact parameters. Finally, through the example of a tropical cyclone damage index, direct impact assessments are presented as powerful tools that distill complex datasets into concise statements on likely impact, and as highly effective communication devices. Capsule: "Combining dynamical modeling of high-impact weather using traditional regional climate models with statistical techniques allows for comprehensive sampling of the full distribution, uncertainty estimation, direct assessment of impacts, and increased confidence in future changes."

climate↗

NASA NTRS2014

Ice Particle Impacts on a Moving Wedge

This work presents the results of an experimental study of ice particle impacts on a moving wedge. The experiment was conducted in the Adverse Environment Rotor Test Stand (AERTS) facility located at Penn State University. The wedge was placed at the tip of a rotating blade. Ice particles shot from a pressure gun intercepted the moving wedge and impacted it at a location along its circular path. The upward velocity of the ice particles varied from 7 to 12 meters per second. Wedge velocities were varied from 0 to 120 meters per second. Wedge angles tested were 0, 30, 45, and 60. High speed imaging combined with backlighting captured the impact allowing observation of the effect of velocity and wedge angle on the impact and the post-impact fragment behavior. It was found that the pressure gun and the rotating wedge could be synchronized to consistently obtain ice particle impacts on the target wedge. It was observed that the number of fragments increase with the normal component of the impact velocity. Particle fragments ejected immediately after impact showed velocities higher than the impact velocity. The results followed the major qualitative features observed by other researchers for hailstone impacts, even though the reduced scale size of the particles used in the present experiment as compared to hailstones was 4:1.

Impacts↗

NASA NTRS2015

Environmental Consequences of Big Nasty Impacts on the Early Earth

The geological record of the Archean Earth is spattered with impact spherules from a dozen or so major cosmic collisions involving Earth and asteroids or comets (Lowe, Byerly 1986, 2015). Extrapolation of the documented deposits suggests that most of these impacts were as big or bigger than the Chicxulub event that famously ended the reign of the thunder lizards. As the Archean impacts were greater, the environmental effects were also greater. The number and magnitude of the impacts is bounded by the lunar record. There are no lunar craters bigger than Chicxulub that date to Earth's mid-to-late Archean. Chance dictates that Earth experienced no more than approximately 10 impacts bigger than Chicxulub between 2.5 billion years and 3.5 billion years, the biggest of which were approximately 30-100 times more energetic, comparable to the Orientale impact on the Moon (1x10 (sup 26) joules). To quantify the thermal consequences of big impacts on old Earth, we model the global flow of energy from the impact into the environment. The model presumes that a significant fraction of the impact energy goes into ejecta that interact with the atmosphere. Much of this energy is initially in rock vapor, melt, and high speed particles. (i) The upper atmosphere is heated by ejecta as they reenter the atmosphere. The mix of hot air, rock vapor, and hot silicates cools by thermal radiation. Rock raindrops fall out as the upper atmosphere cools. (ii) The energy balance of the lower atmosphere is set by radiative exchange with the upper atmosphere and with the surface, and by evaporation of seawater. Susequent cooling is governed by condensation of water vapor. (iii) The oceans are heated by thermal radiation and rock rain and cooled by evaporation. Surface waters become hot and salty; if a deep ocean remains it is relatively cool. Subsequently water vapor condenses to replenish the oceans with hot fresh water (how fresh depending on continental weathering, which might be rather rapid under the circumstances). (iv) The surface temperature of dry land is presumed to be the same as the lower atmosphere. A thermal wave propagates into the land at a rate set by conduction. Impacts not greatly larger than Chicxulub can raise the surface temperature by tens, hundreds, or even thousands of degrees, and evaporate meters to hundreds of meters of water. The biggest should have vitrified exposed dry land. More results are for the talk, as here we have run out of space.

Archean Earth↗

NASA NTRSDate not supplied

A Chlorine Isotope Transect Across the Sudbury Impact Deposits Reveals Enigmatic Isotopic Fractionation

Volatile elements play an important role in a variety of cosmochemical and geochemical processes. As such, there has been significant interest in their abundance and isotopic composition. Chlorine is an important element for tracing these processes because it is incompatible in nearly all minerals, extremely volatile, and strongly hydrophilic [1]. The Cl isotope composition ( 37 Cl/ 35 Cl) of meteoritic components, therefore, can provide useful information regarding the isotopic reservoirs that were present in the early Solar System and any secondary processes that may have occurred on different parent bodies (e.g., [2-4]). There is a relatively narrow range in the Cl isotope compositions of terrestrial, Martian, and chondritic meteorites (δ 37 Cl ~ −6 to +4‰) (e.g., [2,3,5,6]), with exceptions to this being the Moon and Vesta (up to ~ +81‰ and ~ +40‰, respectively) [4, 5, 7-10]. One hypothesis for the extreme Cl isotope fractionation observed on the Moon is degassing following large-scale (possibly even crust-breaching) impact events [7-9]. The role of hypervelocity impacts and impact-generated magmatism in the isotopic evolution of planetary materials, however, has been until recently an area of limited published research with the majority of works focusing on the effects of impact shock (e.g., [10-13]). The ~ 1.85 Ga Sudbury impact crater [14] located in Ontario, Canada, is one of the three largest impact craters on Earth with good exposures of its impact melt sheet and overlying breccias [15,16]. The impact melt sheet, called the Sudbury Igneous Complex (SIC), is up to 5 km thick [17], with an estimated original volume of >10 4 km 3 [18], and differentiated. Recent work demonstrated evaporative loss and isotope fractionation of the moderately volatile element zinc and suggest melt sheets produced by impacts could have a significant effect on the Earth’s volatile inventory [19]. In this study we investigate the abundance and isotopic composition of Cl as well the water abundance of apatite from the SIC and the overlying crater-fill to test the hypothesis that large-scale impacts may have generated the extensive Cl isotopic fractionation observed on the Moon.

Sudbury↗

NASA NTRSDate not supplied

The ESA Hera Mission: Detailed Investigation of the NASA Dart Impact Outcome and Characterization of the Binary Asteroid Didymos

The Hera mission is in development in the Space Safety Program of the European Space Agency (ESA) in collaboration with JAXA for launch in October 2024. It will rendezvous with the binary asteroid (65803) Didymos in early 2027 and over the following 6 months will investigate the properties of Didymos and its small moon Dirmorphos, including the effects of the successful impact of the NASA DART probe. DART was launched on 24 November 2021 at 06:21 UTC and successfully impacted at about 6.1 km/s on the 160 meter-size Dimorphos on 26 September 2022 at 23:14 UTC. Two weeks before impact, it deployed the Light Italian Cubesat for Imaging of Asteroids (LICIACube) that provided images during the few minutes following the impact. A campaign of observations from Earth and space provided distant images of the event, which were used to determine a reduction of 33 min in the orbital period of Dimorphos around Didymos. The Hera mission will investigate the outcome of the DART impact in detail. In particular, it will determine the effects of the impact on Dimorphos’ surface, e.g., whether it produced a crater, and if so its properties, and/or whether it led to global reshaping of Dimorphos. It will accurately measure the mass of Dimorphos, which will allow quantification of the momentum enhancement factor, which is a crucial parameter to evaluate the efficiency of the kinetic impactor technique. Hera will also determine in detail the physical, thermal and compositional properties of the asteroid, including first time measurements of the internal properties, which have a critical influence on the impact outcome. With Hera and DART together, we will have a fully documented deflection test and impact experiment that will allow us to verify our numerical impact models, to be able to extrapolate this deflection test to other asteroids and to improve our understanding of the complex geological properties and response of small asteroids. Hera consists of a mother spacecraft and two cubesats. It will perform the first rendezvous with a binary asteroid, arriving at Didymos about 4 years after DART. Hera will not only contribute significantly to the planetary defense effort by documenting entirely the outcome of the DART impact, it will also greatly advance our understanding of processes in the very low gravity regime of a small asteroidv (Dimorphos) as well as our knowledge of binary asteroids and asteroid geophysics. The mission development is progressing nominally, with the Critical Design Review having been passed in Nov. 2022. The various working groups of the Hera Science Team are working intensively to support this development and be best prepared for the surprises that Hera will offer during its visit to Didymos in 2027.

Asteroid deflection↗

NASA NTRSDate not supplied

Impact, A Tool Suite for Crew Health and Performance System Trade Analyses and Decision to Support - Transition to Operations

Mission planners, systems engineers, and clinicians that support crew health and performance face very difficult choices on upcoming exploration missions. Given that there will be a heavily constrained mass and volume allocation for a medical system on these missions, what medical capability should be manifested to minimize both medical risk and mission risk? Given that not all promising research and technology proposals can be funded, how can proposals be prioritized so that those funded research investments produce the maximum benefit in reducing overall medical risk? The Informing Mission Planning via Analysis of Complex Tradespaces (IMPACT) project seeks to answer these kinds of questions and others to support upcoming exploration missions. IMPACT enables risk-informed and evidence-based trade space analysis for future space vehicles, missions, and systems. This presentation will discuss the long-term HRP and ExMC vision for the larger ecosystem of tools, which include an updated medical database, consisting of an Evidence Library for medical conditions and a medical item database (MedID) for medical resources, dynamic Probabilistic Risk Assessment (PRA) capabilities, System Modeling Language (SysML) models, and contextual data visualizations of output data. IMPACT is the result of a multi-center collaborative effort. The trade space analyses performed by IMPACT can directly inform mission, vehicle, and habitat development by quantifying medical risk, given a design reference mission, crew attributes and a set of medical capabilities. This presentation will update the audience on the development status of the IMPACT tool suite as it comes out of its System Acceptance Review (SAR) and nears Transition to Operations (TTO). It will review IMPACT’s constituent parts, briefly discuss typical outputs, and outline the plans for transitioning to operations, currently scheduled for later in FY24. Recent development successes on the IMPACT project include the integration of the Medical Extensible Dynamic Probabilistic Risk Assessment Tool (MEDPRAT) v2.0 to accommodate segmented missions with multiple carriers and medical systems, full onboarding of the IMPACT Medical Database (IMPACT-MD), clustering medical resources and skills into medical capabilities and mutually-dependent bundles, verification of IMPACT-MD, and the ability to perform trade analyses on different medical sets, different design reference missions (DRM), with different crew complements and extra-vehicular activity (EVA) schedules.

IMPACT↗

NASA NTRSDate not supplied

IMPACT, A Tool Suite for Crew Health and Performance System Trade Analyses and Decision Support- Transition to Operations

IMPACT↗

NASA NTRSDate not supplied

In-Depth Modeling and Simulation Analysis of Artemis Missions Using the Impact Probabilistic Risk Assessment Tool

BACKGROUND The Artemis campaign is a Moon exploration program with a series of six planned missions, five of which will be crewed. These five crewed missions will contain a single mission segment (space flight), or multiple mission segments involving space flight (Orion), lunar landing (LTV) and/or space habitat (Gateway). Each crewed segment faces the risk of unique medical conditions, necessitating medical sets/kits tailored to those specificities. To support and enable a data-driven and evidence-based decision-making process through out a mission’s life cycle, a software tool called IMPACT was developed. Using probabilistic risk assessment (PRA) methodologies, IMPACT (Informing Mission Planning via Analysis of Complex Tradespaces) is a novel tool built for analyzing the possibility of encountering complex medical risks during space flight, and for identifying the medical resources and capabilities needed to treat those potential at-risk medical conditions. IMPACT achieves this by performing hundreds of thousands of Monte Carlo simulations of missions to build aggregate pictures of medical risk. During an extended simulation modeling phase, IMPACT generated analytical results for medical risks, and the medical resources and capabilities to address those risks, for every segment of every crewed Artemis mission. This presentation will highlight the reliability, consistency and validity of IMPACT’s computational modeling techniques and will showcase the library of analytical outcomes generated for the Artemis missions. OVERVIEW During the early stages of IMPACT’s design, architecture and technical requirements collection, “scenarios” (use cases) - achievement goals required for acceptance testing, were identified by stakeholders. IMPACT successfully completed the scenario testing requirements and undertook an extensive operational run phase utilizing a wide range of input combinations with a goal of delivering a cohesive, trustworthy, reliable, vast, and diverse body of evidence. The intent of these modeling runs was to validate consistency in output, ensure solidity of executable operations and to streamline processes by identifying areas requiring efficiency improvements. Using the many missions of Artemis, IMPACT ran variations of operational runs to assess the output for acceptable, as well as unusual characteristics. This rigorous long-term “shakedown” analysis was implemented to help build a collective body of evidence to aid in securing a high level of confidence, reliability, and validity in the output, whether from the applicational components of IMPACT, or the entirety of the operational process. ANTICIPATED ANALYSIS AND CONCLUSION This presentation will discuss the various categories of input criteria; the comparisons in the application of these input criteria to various Artemis missions; the preparation and collection of the body of evidence, and reliability of the computational modeling techniques. This paper serves as an initial analytical overview of IMPACT’s probabilistic risk assessment (PRA) medical risk outputs covering Artemis missions and is not intended to be deemed the official medical response for the Artemis campaign.

Crew Composition↗

DOE OSTI2013

Designing, implementing and monitoring social impact mitigation strategies: Lessons from Forest Industry Structural Adjustment Packages

Social impact mitigation strategies are implemented by the proponents of policies and projects with the intent of reducing the negative, and increasing the positive social impacts of their activities, and facilitating the achievement of policy/project goals. Evaluation of mitigation strategies is critical to improving their future success and cost-effectiveness. This paper evaluates two Forest Industry Structural Adjustment Packages (FISAP) implemented in Australia in the 1990s to 2000s as part of broader policy changes that reduced access to timber from publicly owned native forests. It assesses the effectiveness of the structure, design, implementation and monitoring of the FISAPs, and highlights the interactions between these four elements and their influence on social impacts. The two FISAPs were found to be effective in terms of reducing negative impacts, encouraging positive impacts and contributing towards policy goals, although they did not mitigate negative impacts in all cases, and sometimes interacted with external factors and additional policy changes to contribute to significant short and long term negative impacts. -- Highlights: ► Mitigation strategies aim to reduce negative and enhance positive social impacts ► Mitigation strategy design, implementation, and monitoring are critical to success ► Effective mitigation enhanced the capacity of recipients to respond to change ► Mitigation strategies influenced multiple interacting positive and negative impacts ► Success required good communication, transparency, support, resources and timing.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2013

Social Impact Management Plans: Innovation in corporate and public policy

Social Impact Assessment (SIA) has traditionally been practiced as a predictive study for the regulatory approval of major projects, however, in recent years the drivers and domain of focus for SIA have shifted. This paper details the emergence of Social Impact Management Plans (SIMPs) and undertakes an analysis of innovations in corporate and public policy that have put in place ongoing processes – assessment, management and monitoring – to better identify the nature and scope of the social impacts that might occur during implementation and to proactively respond to change across the lifecycle of developments. Four leading practice examples are analyzed. The International Finance Corporation (IFC) Performance Standards require the preparation of Environmental and Social Management Plans for all projects financed by the IFC identified as having significant environmental and social risks. Anglo American, a major resources company, has introduced a Socio-Economic Assessment Toolbox, which requires mine sites to undertake regular assessments and link these assessments with their internal management systems, monitoring activities and a Social Management Plan. In South Africa, Social and Labour Plans are submitted with an application for a mining or production right. In Queensland, Australia, Social Impact Management Plans were developed as part of an Environmental Impact Statement, which included assessment of social impacts. Collectively these initiatives, and others, are a practical realization of theoretical conceptions of SIA that include management and monitoring as core components of SIA. The paper concludes with an analysis of the implications for the practice of impact assessment including a summary of key criteria for the design and implementation of effective SIMPs. -- Highlights: • Social impact management plans are effective strategies to manage social issues. • They are developed in partnership with regulatory agencies, investors and community. • SIMPs link assessment to ongoing management and address social and community issues. • SIMPs clarify responsibilities in the management of impacts, opportunities and risks. • SIMPs demonstrate a shift to include management as a core component of SIA practice.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2024

Numerical modelling of impact seismic sources using the stress glut theory

SUMMARY Meteorite impacts have proved to be a significant source of seismic signal on the Moon, and have now been recorded on Mars by InSight seismometers. Understanding how impacts produce seismic signal is key to the interpretation of this unique data, and to improve their identification in continuous seismic records. Here, we use the seismic Representation Theorem, and particularly the stress glut theory, to model the seismic motion resulting from impact cratering. The source is described by equivalent forces, some resulting from the impactor momentum transfer, and others from the stress glut, which represents the mechanical effect of plasticity and non linear processes in the source region. We condense these equivalent forces into a point-source with a time-varying single force and nine-component moment tensor. This analytical representation bridges the gap between the complex dynamics of crater formation, and the linear point-source representation classically used in seismology. Using the multiphysics modelling software HOSS, we develop a method to compute the stress glut of an impact, and the associated point-source from hypervelocity impact simulations. For a vertical and an oblique impact at 1000 m s−1, we show that the moment tensor presents a significant deviatoric component. Hence, the source is not an ideal isotropic explosion contrary to previous assumptions, and draws closer to a double couple for the oblique impact. The contribution of the point force to the seismic signal appears negligible. We verify this model by comparing two signals: (1) HOSS is coupled to SPECFEM3D to propagate the near-source signal elastically to remote seismic stations; (2) the point-source model derived from the stress-glut theory is used to generate displacements at the same distance. The comparison shows that the point-source model is accurately simulating the low-frequency impact seismic waveform, and its seismic moment is in trend with Lunar and Martian impact data. High-frequencies discrepancies exist, which are partly related to finite-source effects, but might be further explained by the difference in mathematical framework between classical seismology and HOSS’ numerical modelling.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2017

Cross-border cooperation in inner Scandinavia: A territorial impact assessment

The use of territorial impact assessment procedures is gaining increasing relevance in the European Union policy evaluation processes. However, no concrete territorial impact assessment tools have been applied to evaluating EU cross-border programmes. In this light, this article provides a pioneering analysis on how to make use of territorial impact assessment procedures on cross-border programmes. More specifically, it assesses the main territorial impacts of the Inner Scandinavian INTERREG-A sub-programme, in the last 20 years (1996–2016). It focuses on its impacts on reducing the barrier effect, in all its main dimensions, posed by the presence of the administrative border. The results indicate a quite positive impact of the analysed cross-border cooperation programme, in reducing the barrier effect in all its main dimensions. The obtained potential impact values for each analysed dimension indicate, however, that the ‘economy-technology’ dimension was particularly favoured, following its strategic intervention focus in stimulating the economic activity and the attractiveness of the border area. - Highlights: • A territorial impact assessment method to assess cross-border cooperation is proposed. • This method rationale is based on the main dimensions of the barrier effect. • This method identified positive impacts in all analysed dimensions. • The economy-technological dimension was the most positively impacted one.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2019

Urban heat island impacts on building energy consumption: A review of approaches and findings

Urban heat island (UHI) could have significant impact on building energy consumption by increasing space cooling demand and decreasing space heating demand. However, the impact of UHI on building energy use was understudied due to challenges associated with defining UHI-induced temperature change and evaluating building energy use. In this paper, we reviewed the existing literature to understand the quantitative impact of UHI on building energy, which is represented by the difference in energy consumption of a representative building in urban and rural areas. The previous studies found that UHI could result in a median increase of 19.0% in cooling energy consumption and a median decrease of 18.7% in heating energy consumption. Moreover, the reported UHI impact showed strong spatial variation within and among cities; the impact on cooling energy use ranges between 10% and 120% while the impact on heating ranges between 3% and 45%. Building on the previous studies, the future research could extend the study of UHI impact in four ways: 1) exploring the spatial pattern of the UHI impact within a city by considering the intra-city variation of UHI intensity and building characteristics; 2) investigating the inter-city variation of the UHI impact and the influence of different characteristics such as geographical location, city size, and development stage; 3) expanding studies in developing countries where rapid urbanization is expected in the next few decades; and 4) projecting UHI impact with future patterns of urbanization and climate change.

urbanization, urban heat island, building energy c↗

DOE OSTI2024

Extensive Secondary Cratering From the InSight Sol 1034a Impact Event

Abstract Impact cratering is one of the fundamental processes throughout the history of the Solar System. The formation of new impact craters on planetary bodies has been observed with repeat images from orbiting satellites. However, the time gap between images is often large enough to preclude detailed analysis of smaller‐scale features such as secondary impact craters, which are often removed or buried over a short time period. Here we use a seismic event detected on Mars by the NASA InSight mission to investigate secondary cratering at a new impact crater. We strengthen the case that the seismic event that occurred on Sol 1034 (S1034a) is the result of a new impact cratering event. Using the exact timing of this event from InSight, we investigated the resulting new impact crater in orbital image data. The S1034a impact crater is approximately 9 m in diameter but is responsible for over 900 secondary impact events in the form of low albedo spots that are located at distances of up to almost 7 km from the primary crater. We suggest that the low albedo spots formed from relatively low energy ejecta, with individual ejecta block velocities less than 200 m s −1 . We estimate that the low albedo spots, the main evidence of secondary impact processes at this new impact event, fade within 200–300 days after formation.

Grindrod, P. M. [Natural History Museum London UK]↗

DOE OSTI2023

Linking impact melt redox with crustal weathering regime

Abstract Impact melting and outgassing of impact melts were important processes shaping the crust and atmosphere of early Earth and Mars. The redox state of impact melts influences the gases they release, but the controls on impact melt redox are not well understood. Here, we present Fe micro–X-ray absorption near edge structure (μ-XANES) measurements of a suite of impact melt glasses from Lonar crater, India. As an impact into continental flood basalts, Lonar crater is an ideal analog for impacts into basaltic crust on early Earth and Mars. The Fe-μ-XANES technique permits robust characterization of the Fe3+/ΣFe ratio and therefore redox conditions in Lonar glasses. We found a range in Fe3+/ΣFe of 0.21–0.49 among Lonar glasses, including substantial intraclast variations. We conclude that a primary factor driving these variations was pre-impact oxidative weathering of target rocks. The coupling between crustal weathering regime and speciation of gases released from impact melts implies that impact melt outgassing could act as a feedback mechanism to reinforce prevailing surface redox conditions.

Geology↗

DOE OSTI2012

Literature review on impact of glycolate on the 2H evaporator and the effluent treatment facility

Glycolic acid (GA) is being studied as an alternate reductant in the Defense Waste Processing Facility (DWPF) feed preparation process. It will either be a total or partial replacement for the formic acid that is currently used. A literature review has been conducted on the impact of glycolate on two post-DWPF downstream systems - the 2H Evaporator system and the Effluent Treatment Facility (ETF). The DWPF recycle stream serves as a portion of the feed to the 2H Evaporator. Glycolate enters the evaporator system from the glycolate in the recycle stream. The overhead (i.e., condensed phase) from the 2H Evaporator serves as a portion of the feed to the ETF. The literature search revealed that virtually no impact is anticipated for the 2H Evaporator. Glycolate may help reduce scale formation in the evaporator due to its high complexing ability. The drawback of the solubilizing ability is the potential impact on the criticality analysis of the 2H Evaporator system. It is recommended that at least a theoretical evaluation to confirm the finding that no self-propagating violent reactions with nitrate/nitrites will occur should be performed. Similarly, identification of sources of ignition relevant to glycolate and/or update of the composite flammability analysis to reflect the effects from the glycolate additions for the 2H Evaporator system are in order. An evaluation of the 2H Evaporator criticality analysis is also needed. A determination of the amount or fraction of the glycolate in the evaporator overhead is critical to more accurately assess its impact on the ETF. Hence, use of predictive models like OLI Environmental Simulation Package Software (OLI/ESP) and/or testing are recommended for the determination of the glycolate concentration in the overhead. The impact on the ETF depends on the concentration of glycolate in the ETF feed. The impact is classified as minor for feed glycolate concentrations {le} 33 mg/L or 0.44 mM. The ETF unit operations that will have minor/major impacts are chlorination, pH adjustment, 1st mercury removal, organics removal, 2nd mercury removal, and ion exchange. For minor impacts, the general approach is to use historical process operations data/modeling software like OLI/ESP and/or monitoring/compiled process operations data to resolve any uncertainties with testing as a last resort. For major impacts (i.e., glycolate concentrations > 33 mg/L or 0.44 mM), testing is recommended. No impact is envisaged for the following ETF unit operations regardless of the glycolate concentration - filtration, reverse osmosis, ion exchange resin regeneration, and evaporation.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2024

Air-coupled tsunamis generated from impacts and airbursts: Our understanding before Hunga-Tonga Hunga-Ha'apai

The effort to prevent or mitigate the effects of an impact on Earth is known as planetary defense. A significant component of planetary defense research involves risk assessment. Much of our understanding of the risk from near-Earth objects comes from the geologic record in the form of impact craters, but not all asteroid impacts are crater-forming events. Small asteroids explode before reaching the surface, generating an airburst, and most impacts into the ocean do not penetrate the water to form a crater in the sea floor. The risk from these non-crater-forming ocean impacts and airbursts is difficult to quantify and represents a significant uncertainty in our assessment of the overall threat. We are currently working to better understand impact scenarios that can generate dangerous tsunamis. One of the suggested mechanisms for the production of asteroid–generated tsunamis is by direct coupling of the pressure wave to the water, analogous to the means by which a moving weather front can generate a meteotsunami. To test this hypothesis, we ran a series of airburst simulations and provided time-resolved pressure and wind profiles to use as source functions for tsunami models. We used the CTH hydrocode to model the various airburst scenarios to compare to the results of other simulations and provide time dependent boundary conditions as input to shallow-water wave propagation codes. The strongest and most destructive meteotsunamis are generated by atmospheric pressure oscillations with amplitudes of only a few hPa1 (mbar), corresponding to changes in sea level of a few cm. The resulting wave is strongest when there is a resonance between the ocean and the atmospheric forcing. A Proudman resonance takes place when the atmospheric disturbance’s translational speed (U) equals the longwave phase speed $\sqrt{gh}$ of shallow water wave. Coupling is strongest when the Froude number (Fr=U/c) is unity. A weather front propagates much slower than the speed of sound, so meteotsunamis are most common and dangerous in shallow bodies of water such as the Mediterranean Sea or Lake Michigan. By contrast, the blast wave from an airburst or crater-forming impact propagates at a speed faster than a tsunami in the deepest ocean, and a Proudman resonance cannot be achieved even though the overpressures are orders of magnitude greater. However, blast wave profiles are N-waves in which a sharp shock wave leading to overpressure is followed by a more gradual rarefaction to a much longer-duration underpressure phase. Even though the blast outruns the water wave it is forcing, the tsunami should continue to be driven by the out-of-resonance gradient associated with the suction phase, which may depend strongly on the details of the airburst or impact scenario. The open question is whether there are any conditions under which such an airburst-driven tsunami can be dangerous enough to contribute to the overall impact risk. We have also identified other potential mechanisms for airburst-generated tsunamis: 1) reaction force at the surface from the plume ejected into space, which carries significant momentum, 2) expanding toroidal vortices at the surface, which travel more slowly than the shock wave and can generate a Proudman resonance in relatively shallow ocean (such as continental shelf), and 3) steam explosion from seawater ablation by a “Type II” (Libyan Desert Glass-type) airburst in which the hot vapor jet descends to the surface. On January 15, 2022, the Hunga-Tonga Hunga-Ha’apai volcano, located approximately 60 km north of Tongatapu, the main island of Tonga, violently erupted with a powerful explosion, culminating the period of volcanic activity that started in December of 2021. This event and resulting tsunamis provided an existence proof for the air pressure wave coupling mechanism we proposed. It also suggests that it can be stronger and more significant over much greater distances than we contemplated, leading to global tsunamis associated with impact events on land as well as in the water. Large atmospheric explosions generate global Lamb waves with larger amplitudes, longer periods, and slower speeds than the local and regional blast waves we modeled prior to that event. This paper reviews our analysis and modeling of airburst-driven tsunamis prior to the 2022 Hunga-Tonga Hunga-Ha’apai tsunami, which was the subject of two presentations at the 2023 Planetary Defense Conference and is the subject of another paper currently in preparation.

54 ENVIRONMENTAL SCIENCES↗