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At least 739 records · Page 41

Performance Assessment for the Disposal of Low-Level Waste in the 200 East Area Burial Grounds (Annual Status Report FY 2022)

This annual review provides the projected dose estimates of radionuclide inventories disposed in the 200 East Area Low-Level Waste Burial Grounds (LLBGs) since September 26, 1988. These estimates are calculated using the original dose methodology developed in the performance assessment (PA) analysis (WHC-SD-WM-TI-730). The estimates are compared with the performance objectives defined in U.S. Department of Energy requirements (DOE O 435.1 and its companion documents DOE M 435.1-1 and DOE-STD-5002-2017). All performance objectives are currently satisfied, and operational waste acceptance criteria (HNF-EP-0063) and waste acceptance practices continue to be sufficient to maintain compliance with performance objectives. Inventory estimates and associated dose estimates from future waste disposal actions are unchanged from previous years’ evaluations that indicate potential impacts well below performance objectives; therefore, future compliance with DOE O 435.1 is expected.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Performance Assessment for the Disposal of Low-Level Waste in the 200 West Area Burial Grounds (Annual Status Report FY 2021)

This annual review provides the projected dose estimates of radionuclide inventories disposed in the active 200 West Area Low-Level Waste Burial Grounds (LLBGs) since September 26, 1988. These estimates are calculated using the original dose methodology developed in the performance assessment (PA) analysis (WHC-EP-0645). The estimates are compared with the performance objectives defined in U.S. Department of Energy requirements (DOE O 435.1 and its companion documents DOE M 435.1-1 and DOE-STD-5002-2017). All performance objectives are currently satisfied, and operational waste acceptance criteria (HNF-EP-0063). and waste acceptance practices continue to be sufficient to maintain compliance with performance objectives. Inventory estimates and associated dose estimates from future waste disposal actions are unchanged from previous years’ evaluations that indicate potential impacts well below performance objectives; therefore, future compliance with DOE O 435.1 is expected.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

The Early Career Research Program Annual Progress Report: Using ARM Data and Multiscale Models to Advance the Understanding of Liquid-Phase Cloud Response to Aerosol Perturbation over Ocean and Land

This project aims to study the response of liquid-phase clouds to aerosol perturbation and reduce the related uncertainty in the DOE Earth system model. Specific objectives include: Objective 1: Quantify the aerosol indirect effect on liquid-phase clouds using ARM observations and satellite retrievals while constraining the confounding large-scale conditions; Objective 2: Harness LES case studies, untangle the confounding meteorological impacts on the observed aerosol indirect effect, and identify key cloud processes controlling the net radiative forcing of aerosol-cloud interactions at different spatiotemporal scales; Objective 3: Evaluate the aerosol indirect effect on liquid-phase clouds with process-level understanding in E3SM multiscale model configurations.

54 ENVIRONMENTAL SCIENCES↗

The application of parallel kinetic simulations to laser and electron transport through plasmas (Final technical report)

This is a final report for the grant entitled, “The application of parallel kinetic simulations to laser and electron transport through plasmas”. The objectives of this grant were to significantly advance the fundamental understanding of the nonlinear optics of plasmas and electron transport in high-energy-density laboratory plasmas (HEDLP), including conditions of relevance to Inertial Fusion Energy (IFE). The ultimate goal was to use the understanding to determine how to fully control laser plasma interactions. The primary research tools were our own kinetic particle-in-cell software, OSIRIS, that includes kinetic physics and can run effectively on leadership class computing facilities. Therefore, one objective was to ensure that OSIRIS in continually improved so that it was more accurate and could effectively utilize state-of-the-art computing facilities. Another objective was to attract and train young researchers into the field of high energy density plasma physics. To meet the research objectives, the funds from this proposal were used to conduct research on stimulated Raman scattering (SRS) and enhance our PIC software OSIRIS. It was found that small normalized magnetic fields can in some cases mitigate SRS and that speckles can mutually interact through SRS. It was also found that it is possible for instabilities drive near quarter critical (e.g., the high frequency hybrid instability-HFHI) can generate light waves that propagate back down a density gradient where they can rescatter into the HFHI at 1/16 of the original quarter critical density.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Exploiting Fixed Charge at Selective Contacts for Silicon Photovoltaics

The goal of this work was to examine and exploit fixed interface charges in ultra-thin (0-3 nm thickness) tunnel dielectric layers sandwiched between silicon and selective contact metal oxides (molybdenum oxide, MoO x , titanium oxide, TiO 2 ). Specifically, the interface fixed charge was varied by changing processing conditions and materials over a wide range and the effect on the current-voltage behavior and the Schottky barrier height was quantified. In budget period 1 (year 1), the objective was to grow aluminum oxide tunnel layers with quantified fixed charge over a range of ~1E12 to ~-2E12 cm -2 and combine these with MoO x and TiO 2 layers on Czochralsi (CZ) mono p- and n-Si, respectively. We sought conditions that maximize fixed charge and minimize Schottky barrier height to MoO x contacts to p-Si. This objective, along with investigating the effects of silicon surface terminations, occupied the majority of the project timeline (Q1-Q8) due to complications with high specific contact resistivity values. In the last two quarters of the project period, the objective was to insert HfO2 layers between Si and aluminum oxide layers to quench the fixed charge for layers with otherwise identical thermal history. Another objective was to lower the barrier height at TiO 2 -based contacts on n-type Si, but that was never investigated completely.

14 SOLAR ENERGY↗

Decarbonized Electric Grid: Defining, Measuring, and Integrating Decarbonization into Electricity Sector Policy and Planning

Traditionally, electric grid planning seeks to maintain safe, reliable, efficient, and affordable service for current and future customers. As policies, expectations of the energy system, and the threat landscape evolve, additional objectives for power system planners are emerging, including decarbonization, resilience, and equity. Renewable and clean energy goals, especially in the context of deep decarbonization strategies, are changing the mix of resources on the electric grid and prompting new considerations for grid architecture. The increased frequency and severity of extreme weather events over the last two decades, coupled with cybersecurity concerns, have elevated resilience as a key system need. More recently, there has been greater focus on equity and energy justice in grid planning to ensure that disadvantaged communities are not adversely affected by grid modernization and have equal access to its benefits. In response, new thinking around multi-objective decision planning is exploring improvements in grid planning processes to better integrate approaches to meet decarbonization, resilience, and equity objectives. To provide a foundation for this work, a series of white papers was produced to summarize these emerging objectives.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Resilient Electric Grid: Defining, Measuring, and Integrating Resilience into Electricity Sector Policy and Planning

Traditionally, electric grid planning seeks to maintain safe, reliable, efficient, and affordable service for current and future customers. As policies, expectations of the energy system, and the threat landscape evolve, additional objectives for power system planners are emerging, including decarbonization, resilience, and equity. Renewable and clean energy goals, especially in the context of deep decarbonization strategies, are changing the mix of resources on the electric grid and prompting new considerations for grid architecture. The increased frequency and severity of extreme weather events over the last two decades, coupled with cybersecurity concerns, have elevated resilience as a key system need. More recently, there has been greater focus on equity and energy justice in grid planning to ensure that disadvantaged communities are not adversely affected by grid modernization and have equal access to its benefits. In response, new thinking around multi-objective decision planning is exploring improvements in grid planning processes to better integrate approaches to meet decarbonization, resilience, and equity objectives. To provide a foundation for this work, a series of white papers was produced to summarize these emerging objectives.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Equitable Electric Grid: Defining, Measuring, and Integrating Equity into Electricity Sector Policy and Planning

Traditionally, electric grid planning seeks to maintain safe, reliable, efficient, and affordable service for current and future customers. As policies, expectations of the energy system, and the threat landscape evolve, additional objectives for power system planners are emerging, including decarbonization, resilience, and equity. Renewable and clean energy goals, especially in the context of deep decarbonization strategies, are changing the mix of resources on the electric grid and prompting new considerations for grid architecture. The increased frequency and severity of extreme weather events over the last two decades, coupled with cybersecurity concerns, have elevated resilience as a key system need. More recently, there has been greater focus on equity and energy justice in grid planning to ensure that disadvantaged communities are not adversely affected by grid modernization and have equal access to its benefits. In response, new thinking around multi-objective decision planning is exploring improvements in grid planning processes to better integrate approaches to meet decarbonization, resilience, and equity objectives. To provide a foundation for this work, a series of white papers was produced to summarize these emerging objectives.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Genomes to ecosystem function: Targeting critical knowledge gaps in methanogenesis and translation to updated global biogeochemical models

Natural freshwater temperate wetland systems currently represent the largest natural source of atmospheric methane, but are relatively understudied using systems biology tools (e.g. meta-omics) compared to other high producing methane systems (e.g. peat, tropical, or reconstructed wetlands). Using field investigations at the NOAA operated sentinel site on Lake Erie, methane producing activities and responses to geochemical conditions will be determined along seasonal and spatial gradients (Objective 1). Here, a combination of high-throughput activity and gas measurements, combined with high-resolution systems biology and analytical methods, will provide in depth knowledge of the microbiological, chemical, and physical constraints on methane production in wetlands. Using laboratory microcosms, the formation of anoxic microsites and their capacity to facilitate methane production in wetland soils will be simulated (Objective 2). This objective will validate the findings from the field investigations, offering a more controlled environment for teasing out the role of different yet interrelated variables. Lastly, these field and laboratory data will be used for multi-scale, process-level evaluation of an ecosystem biogeochemical model that accommodates these newly identified processes and parameterizes representation of these processes along relevant environmental gradients (Objective 3).This research will identify multiple interacting geochemical, ecological, and metabolic constraints that are poorly understood, oversimplified, or missing in global biogeochemical methane models. This proposal targets the role of oxygen limitation on methane processes in soil domains, to improve reactive transport models of microbial carbon cycling across terrestrial-aquatic soils and generate data on nutrient cycling activities in Great Lake wetlands. This information could provide new insights into the microbial controllers of Lake Erie eutrophication.

59 BASIC BIOLOGICAL SCIENCES↗

Deliberate Design: Creating Electricity Rates with Purpose

Today’s electricity rates often are legacy designs that do not reflect the dynamics of an evolving power grid or align with current policy objectives. Four steps will assist utilities, regulators, and industry stakeholders in modernizing outdated electricity rate designs. 1. Understand the context for rate design change: The power system is changing at a pace that the industry has not experienced for decades. It is essential to understand the implications of these changes so rates can evolve to remain consistent with changes to the underlying cost profile, customer preferences, and power system requirements. 2. Establish ratemaking objectives: Rates can do more than recover utility costs. They can be a tool for promoting desired outcomes such as improved energy affordability, flexible and efficient electricity consumption, or promoting technology adoption. First, these objectives must be clearly defined and prioritized. 3. Account for tradeoffs when designing new rates: Rate design is the art of balancing tradeoffs. It is essential to understand these tradeoffs when designing new rates, particularly if the rates are being used as a tool for accomplishing policy objectives that extend beyond the basic goal of cost reflectivity. 4. Transition to the new rates with a plan: The move to well-designed rates requires a transition plan. This will ensure that rate design changes do not happen in isolation and are consistent with a long-term, holistic vision. The report, published as an interactive web tool for which the content can be separately downloaded as a standalone document, is intended to allow state energy regulators, utility rates staff, and other industry stakeholders with an interest in rate design to selectively “drill down” on content that is relevant to their interests and situation.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Architecting the Grid Edge: Ensuring Reliability and Resilience

Changes in technology, customer expectations, and business and regulatory environments are rapidly evolving causing fundamental changes in the nation’s electrical infrastructure. Nowhere is this more apparent that at the “grid edge”, where there is an increasing number of new devices and systems, as well as complex new interactions between them. This is leading to the traditional relationship between the end-use customers and their utilities being expanded by an increasing number of stakeholders, each with their own operational and financial objectives, governed by regulatory policy. While there are concerns about the rapidly increasing complexity negatively impacting reliable and resilience of the electrical infrastructure, these changes are also bringing new resources and opportunities that hold great potential if they can be properly coordinated. This white paper outlines the considerations for the coordination of multi-stakeholder objectives with electric utility requirements using the concept of grid services. Describing a framework that enables new stakeholders to achieve their local technical and economic objectives, while simultaneously delivering operational benefits to the electrical infrastructure. The concepts of grid architecture are presented as a tool to evaluate how stakeholders might participate in, and benefit from, services, and how utilities can make decision on the reliance on services to ensure reliability and resilience, translating abstract concepts into actionable information for utilities and grid edge stakeholders. The end result of proper coordination, informed by grid architecture, will be a range of new devices and systems, operated by new stakeholders, achieving their local objectives while also increasing the reliability, resilience, security, and affordability of the nation’s critical electrical infrastructure.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Architecting the Grid Edge: Ensuring Reliability and Resilience

Changes in technology, customer expectations, and business and regulatory environments are rapidly evolving causing fundamental changes in the nation’s electrical infrastructure. Nowhere is this more apparent that at the “grid edge”, where there is an increasing number of new devices and systems, as well as complex new interactions between them. This is leading to the traditional relationship between the end-use customers and their utilities being expanded by an increasing number of stakeholders, each with their own operational and financial objectives, governed by regulatory policy. While there are concerns about the rapidly increasing complexity negatively impacting reliable and resilience of the electrical infrastructure, these changes are also bringing new resources and opportunities that hold great potential if they can be properly coordinated. This white paper outlines the considerations for the coordination of multi-stakeholder objectives with electric utility requirements using the concept of grid services. Describing a framework that enables new stakeholders to achieve their local technical and economic objectives, while simultaneously delivering operational benefits to the electrical infrastructure. The concepts of grid architecture are presented as a tool to evaluate how stakeholders might participate in, and benefit from, services, and how utilities can make decision on the reliance on services to ensure reliability and resilience, translating abstract concepts into actionable information for utilities and grid edge stakeholders. The end result of proper coordination, informed by grid architecture, will be a range of new devices and systems, operated by new stakeholders, achieving their local objectives while also increasing the reliability, resilience, security, and affordability of the nation’s critical electrical infrastructure.

24 POWER TRANSMISSION AND DISTRIBUTION↗

PV Fleet Performance Data Initiative Final Technical Report (FTR)

Improved analysis and reporting of photovoltaic (PV) field performance increases the certainty of owners and financiers that systems will perform as expected. Advanced module technologies (e.g., PERC, HJT, and bifacial) introduce new degradation mechanisms and performance characteristics. This project will leverage data from the ever-increasing PV fleet to develop models and understanding of the field performance of existing and new technologies. Please see our list of public reports at https://www.nrel.gov/pv/fleet-performance-data-initiative.html. Objective 1: Support the global PV industry with scalable, robust data analysis tools that reduce the uncertainty of PV system performance and loss calculation. Objective 2: Reduce perceived risk arising from degradation rate, soiling loss, and system availability by publishing detailed statistics on U.S. fleet performance. Objective 3: Highlight factors leading to system underperformance including module type, climate, mounting configuration, etc. Objective 4: Enable continued high system performance in modern PV systems, as turnover and advances in technology bring new suppliers and high-efficiency modules into the market.

14 SOLAR ENERGY↗

Pantex Plant Ogallala Aquifer and Perched Groundwater Contingency Plan

The Pantex Plant Ogallala Aquifer and Perched Groundwater Contingency Plan has been developed in accordance with the requirements identified in the: • Interagency Agreement for the Pantex Superfund Site, Article 8.5 Work to be Performed, • Compliance Plan Provision of Hazardous Waste Permit No. 50284, and • Record of Decision for Groundwater, Soil, and Associated Media, Pantex Plant. A Long‐Term Monitoring System Design has been designed to monitor conditions in the perched groundwater including changes in the perched aquifer as a result of implementing the response actions. Monitoring is required for verifying the effectiveness of perched groundwater response actions (i.e., conditions in the perched aquifer are being affected as intended) and for confirming that the perched aquifer and Ogallala Aquifer characterization as defined in the Resource Conservation and Recovery Act Facility Investigation Report and the Corrective Measure Studies/Feasibility Study remains accurate. If monitoring results obtained through the monitoring network identify an unexpected condition or deviation, contingent actions will be considered and implemented as necessary to ensure continued protection of the Ogallala Aquifer and human health and the environment. Potential deviations to expected technology performance may be encountered for each of the four primary response actions that compose the selected remedy for perched groundwater; Playa 1 Pump and Treat System, Southeast Area Pump and Treat System, Southeast Area In‐Situ Bioremediation System (comprised of the Southeast In‐Situ Bioremediation System Original System, Southeast Area In‐Situ Bioremediation System Extension System, Offsite In‐Situ Bioremediation System, Perchlorate/Chromium ISB, Northeast ISB and County Road 8 ISB), and Zone 11 In‐Situ Bioremediation System. Monitoring will also be conducted to determine if there are deviations to the expected characterization, e.g., contaminants not expected as a result of the RCRA Facility Investigation characterization. Deviations to expected conditions in the Ogallala Aquifer could also be encountered if the response actions in the perched groundwater are not performing as expected, i.e., preventing contaminants from migrating to the Ogallala Aquifer. Currently, Pantex has begun investigation of detections of high explosives above groundwater protection standards in wells on the Texas Tech University property and a plume that is moving to the northeast from that area. Due to those detections, this Plan recognizes the fact that future detections in the Ogallala will be focused on first‐ time detections of analytes. After a remedy is determined, this Plan will require modification to address-deviations and contingent actions. This Plan was developed to identify the contingent actions necessary to mitigate impacts resulting from deviations to site conditions or response action performance. The Plan defines the environmental problem being addressed by the response actions, clarifies the expected conditions and objectives of the response actions, and identifies the potential deviations to the response actions (due to site conditions or technology performance) that could be encountered. The deviations were evaluated to determine the likelihood of occurrence, potential impact, and time to respond to avoid impact. The Plan also identifies the monitoring outlined in the Long‐Term Monitoring System Design Report (Consolidated Nuclear Security, 2024) and Sampling Analysis Plan (PanTeXas Deterrence, 2024) that will be used to detect the deviations. Lastly, the Plan specifies the contingent actions that could be implemented in response to the deviations. Because each response focuses on a discrete portion of the perched aquifer and contaminant plume, each response action has a different set of expected conditions, and therefore differing impacts from deviations to the site and technology expectations. As a result, the contingent actions are identified for each response action and potential deviation including specific constituents, location, and conditions. If deviations are encountered that impact the ability of the response action to meet performance objectives, the contingent actions will be focused on ensuring the response action can meet the performance objective. Contingent actions may be implemented as interim actions (ISMs/removal actions) in accordance with the Record of Decision, Interagency Agreement, and Hazardous Waste Permit‐50284, if warranted by the specific circumstances. For deviations to site characterization expected conditions, the contingent action will focus on determination of the source of the deviation, determination of the appropriate response, and evaluation of additional work to be completed. However, if the deviation to characterization impacts the performance of the response action, the contingent action will again focus on ensuring performance objectives can be met. Early source term removals and cleanup actions have been implemented to protect the Ogallala Aquifer. Because of these actions and based on modeling results, the expected conditions in the Ogallala Aquifer are that constituents of concern will not be detected above the Groundwater Protection Standards (GWPSs) nor will they reach potential points of exposure above the GWPS. The primary deviation of concern for the Ogallala is if constituents are detected in the Ogallala Aquifer near or above GWPSs. If it occurs, this change in expected conditions would require further evaluation of site and contaminant characteristics to determine an appropriate course of action. The evaluation would include additional monitoring, source identification, implementation of interim protective measures (if necessary), and delineation of extent. These evaluations are necessary to determine an appropriate response action for the Ogallala. The primary goal of the Plan is to provide for the continued protection of the Ogallala Aquifer and the health of its consumers. In recognition, this Plan presents a flexible and rational approach for making future decisions associated with confirming the change in perched and Ogallala aquifer conditions and identifying a response (technical activities, changes to response actions, regulatory oversight, and public involvement).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Image Alignment and Flat-Field Correction of Film and Computed Radiography Images on the LLNL Flash Testbed

Computed radiography (CR) imaging plates and film are used in HEAF firing tanks and in the NDE group. The imaging plates allow for the creation of high-resolution digital images with flash X-ray (FXR). A typical treatment of flash X-ray radiographs is flat-field correction, where the image from an experiment is normalized by a “flat-field” or “bright-field” image. This flat-field image is taken in an identical configuration to the experimental image, but without the object or experiment in the field of view (FOV). This treatment reduces spatial effects from the FXR spot size and detector misalignment, as each pixel value in the corrected image represents a ratio of collected radiation with the object in FOV to the collected radiation without the object in FOV. One challenge in the creation of a corrected image is the misalignment of the CR plate or film pack between capturing the flat-field image and the experimental image. Fiducial structures can remedy this issue. Small (3.18mm) stainless steel ball bearings serve as good fiducial structures due to their small size and high radiographic contrast. Spheres are view-agnostic geometry, always presenting a circular cross section no matter the orientation. This process was developed for images from the flash X-ray testbed. The flash testbed was used to compare the X-ray transmission at different thicknesses of aluminum and copper step wedges. Each step wedge section is a rectangular shape, so evaluation is made much simpler if the rectangles are not rotated with respect to the image. This alignment process aligns the object and flat-field images together and leaves the rectangles of each step aligned with the image.

36 MATERIALS SCIENCE↗

Data Qualification Report: SRNL Glass Composition-Properties (ComPro) Database

The Savannah River National Laboratory Glass Composition-Properties (ComPro) database is an extensive database containing pertinent composition and durability data to support the accelerated clean-up mission at the Defense Waste Processing Facility. The activities described in this data qualification report were performed to support the information contained in the database. There were two objectives of the original data qualification process. The first objective was to review supporting documentation to determine if DOE/RW-0333P Quality Assurance Requirements and Description had been implemented during the original work. If the DOE/RW-0333P Quality Assurance Requirements and Description had not been directly implemented during the original work, the second objective was to determine if the controls that were used were adequate to meet the intent of the DOE/RW-0333P Quality Assurance Requirements and Description. The results of these two objectives and the activities performed to support these decisions are described in this document. An assessment of each dataset was made to determine if the data were RW-0333P Compliant, RW-0333P Equivalent or Non-RW-0333P Compliant. The original data qualification was performed in accordance with E7, Conduct of Engineering Manual, Procedure 3.70, Revision 4, Qualification of Data. The specific method that was used was Equivalent Controls as described in E7, 3.70. Revision 2 of this document adds supporting information for the RW-0333P Compliant datasets added to Revision 3 of the database.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Final Report for CSP Tower Public Opinion and Education Project

As part of the CSP Plant Optimization Study for the California Power Market (DE-EE0009809) the project wanted to understand the public’s opinion of the technology and and explore the types of community engagement that is needed to support such development. The initial objectives for the public perception activities were twofold. The primary objective was to gather public opinion and feedback from the communities living near the two operating solar power tower plants, Ivanpah and Crescent Dunes, and to distill lessons learned from the community engagement conducted before, during, and after the plants were developed to inform future development. This included outreach to nearby airports. The other objective was to gauge public opinion about large-scale solar, specifically CSP towers, to start educating the public on the benefits and to begin building relationships with communities of interest, initially targeting the Kingman, Arizona area. The objectives shifted after the first exploratory trip to Ivanpah and Kingman, however, as it became apparent that it would be challenging to gather public opinion from the community surrounding Ivanpah that could be useful for other community profiles, and the company wasn’t ready to address the concerns in Kingman. Another area was chosen, therefore, to represent those where future development is possible. The recently published Lawrence Berkeley National Lab Perceptions of Large-Scale Solar Project Neighbors Study exemplified public perception polling based on social science and served as the foundation for the survey questions taken to the field. The intent was to ensure that people knew their input was valued and that the time they spent was valuable for the participant as well. It has been noted in the literature that in-person interaction has greater benefits than activities online or via mail, as well as limits the expense.

14 SOLAR ENERGY↗

Web-Based Tools for Data-Informed Remedy Optimization: Software Theory and User Guide

This report documents the development and application of two web-based decision-support tools for pump-and-treat (P&T) groundwater remediation systems: PTOLEMY (Pump-and-Treat Optimized Location Evaluation to Maximize Yields) and OPTIMA (Optimization for Pump-and-Treat Implementation, Management, & Assessment). These tools enhance remedy design and management by leveraging advanced computational methods – specifically deep learning and multi-objective optimization – within a user-friendly platform. By integrating data-driven models with established hydrogeological knowledge, PTOLEMY and OPTIMA enable more efficient evaluation of well placement and operational strategies, helping site managers balance multiple remediation objectives under complex conditions. Both tools are implemented as modules within the SOCRATES (Suite Of Comprehensive Rapid Analysis Tools for Environmental Sites) web platform, which provides data access, visualization, and analytics to support remedy optimization across sites in the U.S. Department of Energy Office of Environmental Management complex. PTOLEMY is a rapid screening module designed to identify promising locations for new extraction wells. It employs a multi-channel three-dimensional convolutional neural network (MC3D-CNN) trained on high-fidelity simulation data to predict the relative performance (in terms of contaminant mass recovery) of potential well sites. Through an interactive web interface, PTOLEMY visualizes the probability of high performance across a site, highlighting areas where an extraction well is likely to yield above-threshold contaminant removal over a multi-year period. PTOLEMY’s map-based displays and exportable results support transparent communication of screening analyses. By focusing attention on the most favorable candidate locations, the tool augments traditional engineering judgment and physics-based modeling, providing a data informed basis for subsequent detailed evaluations. OPTIMA is a multi objective optimization module designed to find wellfield layouts and operating schedules that meet various cleanup goals. It quickly evaluates thousands of candidate setups – combinations of well locations, timing, and rates – and returns a small set of best trade-off options for comparison. At its core, OPTIMA uses a U-Net-based surrogate model – a deep-learning emulator of a groundwater flow and transport simulator – to dramatically accelerate scenario evaluations. Coupling this fast surrogate with the NSGA-II (Non-dominated Sorting Genetic Algorithm II) evolutionary algorithm, OPTIMA explores a wide decision space of well locations and schedules to identify Pareto-optimal solutions that trade off key objectives (e.g., minimizing cleanup time, maximizing contaminant mass removal, and minimizing plume extent). The tool outputs a family of optimal configurations and visualizes their trade-offs (Pareto frontiers of cleanup metrics and maps of optimized well placements). Site managers can use these results to understand the range of viable strategies and to select candidate designs for more detailed verification. OPTIMA is currently under active development and not yet fully released; this guide provides early documentation to support planning and gather user feedback.

54 ENVIRONMENTAL SCIENCES↗