Digital Commons Network^™

Epri Ccp Beneficiation Research Update, Benjamin Gallagher, Patrick Webb

World of Coal Ash Proceedings

Coal combustion products (CCPs) are frequently utilized as supplementary materials in cement and concrete manufacturing. With an estimated 2 billion metric tons stored in repositories across the United States, interest in beneficial use has expanded beyond class F fly ash to include ponded and high-LOI ash. Beneficiation provides a critical pathway for managing CCP repositories, particularly under closure-by-removal strategies, and where ash sources have historically been difficult to process. Research conducted at EPRI’s Ash Beneficial Use Center (ABUC) examines the feasibility of processing these ash types into usable products and offers insights into repository variability and classification. Furthermore, the study …

Risk Evaluation Of Small Coal Combustion Residual Management Unit (Ccrmu) Fills, Andrew Bittner, John Kondziolka, Qian Zhang, Masoud Arshadi

World of Coal Ash Proceedings

US EPA expanded the scope of CCR regulations in 2024 to areas of historical CCR placement not regulated under the 2015 CCR rule, including CCR used as fill. US EPA presented new risk analyses specific to CCRMU fills and defined different regulations for CCRMU fills from 1 to 1,000 tons, noting uncertainty as to whether there was a size of CCRMU fill below which acceptable risks could be expected. This research fills US EPA's stated data gap by modeling and analyzing impacts from small CCRMU fills. Modeling was conducted using the same methods, models, and most of the same inputs …

Investigating The Performance Of Processed Stockpile Fly Ash For Low Carbon Concrete, Michael Mccarthy, Arfas Habeeb, Laszlo Csetenyi, Roderick Jones

World of Coal Ash Proceedings

Reducing embodied carbon in concrete has increasingly focused on clinker substitution through the use of supplementary cementitious materials (SCMs). However, the local availability of fly ash, a widely used SCM in the UK, offering benefits in this role, has reduced over the past decade, as coal-fired electricity generating plants have gradually been taken out of service. Attention has, therefore, increasingly focused on fly ash from stockpile and landfill sites to maintain supply, i.e., material not used following production and put into storage. Most UK fly ash originated from the burning of bituminous coal, producing low-lime siliceous material, which although undergoing …

Solar Solution For Closed Ccr Units And Adjacent Land, Chris Fairey

World of Coal Ash Proceedings

Solar Solution for Closed CCR Units and Adjacent Land Chris Fairey1, Kenny Hughes1 1Watershed Geo, 1125 Sanctuary Pkwy, Suite 180, Alpharetta, GA 30009 KEYWORDS: Solar, Racking, Brownfield, Greenfield, Slopes, PowerCap® ABSTRACT With the reduction in coal fired power generation, there is a consistent trend in the industry to supplement generation with solar power. The property located within and surrounding these decommissioned power plants offers a significant opportunity to create a renewable solar power asset. The PowerCap® Nail to Rail System, developed by Watershed Geo, is an advanced solar racking solution designed for sites that do not require environmental closure such …

Abundances Of Elements In Global Coals, Shifeng Dai

World of Coal Ash Proceedings

The abundance of elements in coal is important not only because it provides a solid scientific and practical foundation for various geochemical comparisons, but also because it helps address broader questions in Earth Sciences. In this study, data on major and trace elements in global coals comprising hundreds of thousands of coal samples were compiled from peer-reviewed journal articles, books, various databases, dissertations, and technical reports. These data formed the basis for estimating element abundances in global coals presented in this study. All collected data were rigorously screened for reliability, and any records with questionable quality were excluded from the …

Consolidation Modeling To Support Closure Planning Of An Upstream Raise Ccr Surface Impoundment Containing Fgd Material, Tanya Walkenbach, Craig Schuettpelz, Todd Stong, Shane Stockdill

World of Coal Ash Proceedings

Rainbow Energy Center’s (REC’s) Coal Creek Station has managed calcium sulfite flue gas desulfurization (FGD) material in composite-lined upstream raise surface impoundments since 2001. The upstream raise surface impoundment utilizes bottom ash (drainage zone) and fly ash (structural zone) produced at Coal Creek Station to contain the FGD placement. FGD material was hydraulically sluiced to the center of the 110-acre Upstream Raise 92 (UR92) coal combustion residual (CCR) unit between 2001 and 2021. The FGD was deposited to a maximum thickness of approximately 100 feet in the center of the unit. Significant consolidation of FGD material occurred with subsequent FGD …

Investigation Of A Historical Coal Combustion Residuals Management Unit (Ccrmu), Todd Stong, Shane Stockdill, Erin Hunter

World of Coal Ash Proceedings

Rainbow Energy Center’s (REC’s) Coal Creek Station has managed coal combustion residuals (CCR) in various engineered impoundments and landfills since plant operation began in 1978. Since then, waste containment methods have evolved resulting in significant changes to their CCR management practice. In the late 1980s and early 1990s REC closed several existing CCR units with natural soil liners and constructed several new CCR units with composite liner systems. One of the closed units was an area now referred to as North Section 16, an impoundment that received CCR including bottom ash, fly ash, and flue gas desulfurization material. North Section …

Transportation Logistics Panel, John Ward, Andrew Vollmer, Tracy Zea, Marci Jenks

World of Coal Ash Proceedings

As the industry shifts from freshly generated ash to harvested materials and advanced utilization, logistics is becoming one of the primary drivers of project success or failure. This moderated panel will explore how sourcing, transportation, and storage realities are changing — and what project teams most often underestimate when working with harvested coal ash. Panelists will discuss what breaks, what becomes more complex, and how logistics considerations are reshaping planning and development.

Optimization Of Remedial Strategies For Ccr Site Corrective Action Through Advanced Geochemical Modeling, Cole Mayer, Pj Nolan

World of Coal Ash Proceedings

The power industry is actively designing and implementing corrective measures for Coal Combustion Residuals (CCR). In many cases, these measures include active remedies such as pump and treat, in-situ injection, or reactive barriers, all of which demand a thorough understanding of the underlying geochemical system. Depending on the geochemical characteristics of an aquifer, different chemical reagents can achieve varying degrees of success or even be detrimental to the remediation of the site. Advanced geochemical modeling is an invaluable tool for developing a remedy that is optimized to the site-specific geological, hydrological, and geochemical environment. In the case study presented here, …

Application Of Stable Isotopes In An Alternative Source Demonstration, Alison O'Connor

World of Coal Ash Proceedings

Stable isotope analysis is commonly used in age dating, provenance studies and to differentiate between sources of groundwater. Multiple studies have shown that strontium and boron isotopic ratios can be successfully used in identifying CCR impacts to groundwater. This talk presents an applied case study using boron and strontium isotopes in conjunction with additional geochemical approaches in an alternative source demonstration. Boron and strontium isotopes were measured in both groundwater and CCR leachate over sampling events from 2019 to 2025. The data revealed that strontium and boron isotopic signatures in groundwater near the CCR unit differed significantly from both site-specific …

Distinguishing Ccp From Nuclear Impacts In Groundwater, Lea Millet

World of Coal Ash Proceedings

As the energy transition from fossil fuels to other generation technologies continues, many companies worldwide are evaluating the feasibility of constructing nuclear power plants at sites previously used for coal-powered generation. Thermal power plant sites offer advantages for siting nuclear generation such as proximity to cooling water and grid connections; however existing impacts to groundwater from coal combustion product (CCP) management units may confound monitoring programs designed to detect impacts from nuclear operations. For example, boron and lithium may be present in waters associated with CCP management and nuclear power plant operations, and potassium that often has concentrations above background …

Ccr Landfill Closure Challenges, Solutions And Innovation, Jay Mokotoff, Drew Browning, Steve Applegate

World of Coal Ash Proceedings

CCR landfills can present unique design and construction challenges for the industry when closing these units at the end of their life. In comparison to CCR surface impoundments, CCR landfills typically have greater flexibility under the CCR Rule for operations and beneficial use purposes and may not have defined closure dates which results in some of these closures extending further into the future. However, as coal burning plants continue to shudder, the closure of these landfills is rapidly approaching. This presentation will focus on the challenging site conditions, site specific considerations and potential solutions when designing and constructing the landfill …

Engineering Granulometry To Optimize Performance Of Reclaimed Ash, Russell Hill

World of Coal Ash Proceedings

As utility production of fresh fly ash declines, the concrete industry is turning to reclaimed and beneficiated materials to maintain reliable SCM supply. This transition creates an opportunity not only to secure volumes but to engineer improved performance. The ReCinis™ beneficiation process enables this by providing controls that tune particle-size distribution (PSD), sphericity, packing behavior, surface area, and surface activation. Processing trials show that blends combining fine ground fractions with spherical, broad-graded hydrocyclone overflow (OF) materials can balance high reactivity with favorable rheology. Mechanochemical activation during grinding appears to increase reactivity beyond what surface-area metrics alone predict, likely through removal …

Alternative Cover Permitting And The Ccr Rule, Evan Andrews, Victor Damasceno

World of Coal Ash Proceedings

Federal rules (40 CFR Parts 9, 257 and 261) that regulate coal combustion residuals (CCR) created a significant demand associated with closure of coal ash management and storage facilities using liner systems. Timelines associated with these facility closures combined with substantial project scale and potential for future mining /reuse has driven the need for closure systems that perform beyond the prescriptive soil / geomembrane caps outlined in the federal regulations. As outlined in section 257.102 (d)(3)(i) of the CCR Rule, the standard cover system must include an infiltration layer of at least 18 inches of earthen material and an erosion …

Sustainability And Waste Diversion At Tva Shawnee "Project Phoenix", Bryan Jacob, Shane Harris

World of Coal Ash Proceedings

An engineered turf closure system can serve as an ideal foundation for a solar energy system to be installed atop coal combustion residual (CCR) impoundments. This approach not only enables productive power generation during the post-closure period, it also preserves opportunities for recovery and beneficial use of CCR material in the future. “Project Phoenix” at TVA’s Shawnee Fossil Plant offers an illustrative example. This paper will cover the sustainability benefits of the companion ClosureTurf® and PowerCap® systems installed at that site as well as waste diversion activities undertaken during construction to recycle as much as practical and minimize waste destined …

Demystifying Large Language Models: How Ai Is Transforming Data, Compliance, And Decision-Making In Coal Ash And Environmental Management, Scott Pfeiffer

World of Coal Ash Proceedings

The environmental and coal combustion residuals (CCR) industries generate vast amounts of information—from groundwater monitoring reports and RCRA documentation to closure plans and analytical data. Managing, interpreting, and communicating this information is a growing challenge for utilities, regulators, and consultants alike. Large Language Models (LLMs), such as OpenAI’s GPT architecture, represent a breakthrough in how organizations can interact with their technical data. These models use deep neural networks trained on billions of words to understand, summarize, and generate language with human-like accuracy. When securely adapted for enterprise use, LLMs can automate routine reporting, extract data from technical documents, generate regulatory …

Expert Perspectives On The U.S. Coal Combustion Products Market – Now, Then, And The Future, Mark Rokoff, David Cox, Walter Lemaire, John Ward

World of Coal Ash Proceedings

This panel discussion will explore the continued evolution of the U.S. coal combustion products market, with a focus on the impacts of dynamic regulatory and market forces. Invited expert panelists will share perspectives on developments over the past several years (building on discussions from WOCA 2022 and WOCA 2024), current conditions, and expected future trends—particularly those likely to shape the market between 2026 and 2030. The discussion will address the interrelated markets for engineering, construction, and beneficiation of ash from both operating and inactive plants. Panelists will offer perspectives relevant to the full coal ash industry, from owner/operator organizations to …

Subsurface Delineation Of Coal Combustion Residuals Using Multiple Geophysical Methods, Eric Hageman, Adam Rak, Thomas Jordan, Kate Mckinley

World of Coal Ash Proceedings

Geophysical techniques provide alternative methods of Coal Combustion Residual (CCR) delineation and characterization to supplement more invasive boring programs used for beneficial reuse planning. A demonstration project was designed to characterize the electromagnetic and seismic stratigraphy of CCR material and test the effectiveness of three geophysical techniques: Electrical Resistivity Imaging (ERI), Transient Electromagnetic (TEM) induction, and Multi-channel Analysis of Surface Wave (MASW). The demonstration project was completed at a dry-stack CCR unit containing a variety of CCR ash, gypsum, and thin layers of drainage aggregate (limestone). During a single-day deployment, several geophysical survey tests were conducted in specific areas of …

Analysis Of Approximations In Flash Thermal Diffusivity Measurements Using High‑Fidelity Simulations, Tage T. Burnett, Jakob G. Bates, Matthew R. Jones, Christopher R. Dillon, John Tencer

Faculty Publications

Thermal diffusivity is an important material property for understanding and characterizing transient behavior in many heat transfer applications. This study investigates the accuracy and approximations of inverse mathematical models for measuring thermal diffusivity of materials via the widely used Flash Method. High-fidelity simulations of the Flash Method in copper, silicon carbide, silicon, and glass were performed as numerical experiments and included physics such as in-depth absorption, radial conduction, and surface convection. Data from those numerical experiments were used to estimate material thermal diffusivity using seven traditional and new inverse models. Parker’s original model had relative errors 𝜖< 5% when the approximations it makes were enforced in numerical experiments. Newer models performed well even when experimental restrictions were relaxed. Models that include radial heat conduction were capable of accurately measuring thermal diffusivity (𝜖< 1%) when a Gaussian energy source was used. Models with radial conduction and in-depth material absorption of the laser source could calculate thermal diffusivity for semi-transparent materials such as silicon (𝜖< 1%) and even transparent materials like glass (𝜖< 10%). Convective losses from the material’s front surface had a negligible impact on measurements except for very low thermal diffusivity materials. Using temperatures from many locations of the test material’s surface increased resilience to noise, reducing the distribution of thermal diffusivity measurements by more than an order of magnitude. The models developed in this study could enable a more relaxed Flash Method experimental setup that maintains thermal diffusivity accuracy and extend the utility of the Flash Method to semitransparent materials.

Challenging Stem Learning Spaces: The Paradigm Of Contemplative Traditions As The Bedrock Of Creativity And Healing, Raaghav Pandya, Christopher Emdin

Journal of Contemplative and Holistic Education

As the post-pandemic classroom and pedagogy evolve to remedy oppressive norms, young people’s mental health and alienation has taken front stage (Rahmani & Zitouni, 2022). Traditional STEM learning spaces often teach inquiry as a linear, non-deviated approach to problems about self and nature (Hrisa & Psillos, 2022). Furthermore, because our classrooms often strip students and educators of their inherent creative abilities through constant assessments, improvement scales, and market-driven expectations, classrooms cease to become places of healing (Pandya, 2021). Eastern wisdom traditions and their associated philosophies provide a unique pedagogical lens that emphasizes a deep inquiry into self, empathy, and creativity …

Aerodynamic Performance Of Grid Fins As High Lift Devices, Luke Jeffrey Krick

Senior Honors Theses

Flaps are used in almost all aircraft to increase the amount of lift the wings can produce at low speeds. However, the flaps also increase the amount of drag experienced by the aircraft. The drag induced by the flaps causes energy loss and is unfavorable for aircraft effectiveness. In recent years, grid fins have become a popular choice for aircraft and armaments to control their orientation. First developed for launch escape towers, grid fins are made up of lines that cut the fin into many quadrants, leaving the fin with multiple rectangular shaped open areas. The aim of this study …

Lightweight Attestation Techniques For The Industrial Internet Of Things, Syed Owais Athar

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The Industrial Internet of Things (IIoT) has transformed critical infrastructure by integrating programmable logic controllers (PLCs) with connected sensors, actuators, and supervisory systems. While these advancements enhance operational efficiency, they also increase exposure to sophisticated cyber-physical threats, particularly through malicious modifications of PLC programs. Existing attestation methods either impose significant computational burdens by performing continuous verification or rely on detailed physical models that are often impractical to maintain across heterogeneous environments.

The first part of this thesis focuses on DuAtt, a dual-layer attestation scheme that integrates a physical process–based anomaly detection mechanism with a targeted attestation of the PLC program. …

Leveraging Information Theory And Ecological Network Analysis To Monitor Communication Networks In A Student Aerospace Team, Christine Sessions

Doctoral Dissertations and Master's Theses

Effective communication is a critical component of successful collaboration in group projects and team settings. However, systematically tracking and analyzing team communications can be challenging, especially in complex, multi-member teams such as those found in the aerospace industry. This paper explores an information-theoretic approach that leverages encoding techniques and graph theory to analyze communication networks within a university’s multi-year, student-led cubesat design project (Project COMET). By utilizing Shannon Entropy as a measure of information flow, encoding communication patterns, and analyzing Ecological Network Analysis parameters, this research aims to understand how an Embry-Riddle Aeronautical University student project team evolves over the …

Adaptive Control Combined With Integral Concurrent Learning For Trajectory Tracking Near Asteroids, Alvaro Diaz Rodrigo

Doctoral Dissertations and Master's Theses

Close-proximity operations in the vicinity of Near-Earth Asteroids (NEAs) are essential for scientific studies and possible future planetary-defense missions. Unlike motion around large celestial bodies, spacecraft dynamics near small, rotating asteroids are dominated by weak, highly irregular gravity fields. While full characterization of an asteroid’s shape enables high-fidelity gravitational modeling, such information is typically unavailable in realistic mission scenarios, and in-situ exploration is often required. As a result, the forces acting on the spacecraft cannot be modeled accurately in advance, leading to significant uncertainty in the equations of motion and challenging guidance and control strategies. To address these challenges, the …

Data-Driven Physical-Layer Optimization For Rf And Optical Communications: Transmitarray Metasurfaces, Contextual-Bandit Mud, And Coherent Optical Links, Chengtao M. Xu

Doctoral Dissertations and Master's Theses

This dissertation studies three physical-layer optimization problems that share a common difficulty: the forward model, whether an electromagnetic solver or a statistical channel model, is either too expensive to evaluate at design scale or too unstable to hold across a single processing block. The first two problems are treated in their own right, as problems in antenna design and in multi-user detection over time-variant channels; the third carries the methodology onto a coherent optical link, where size, weight, and power constraints make a small-satellite deployment the natural target.

The antenna work targets a tri-layer pixelated unit cell fabricated on Avient …

Engineering Design And Analysis Using Creo® Cad, Cae, And Manufacturing Applications, Swapnil Moon

Open and Affordable Textbooks

This textbook presents a structured approach to computer-aided design using Creo, integrating CAD, CAE, and CAM workflows within a unified engineering framework. The material emphasizes parametric modeling, design intent, and feature-based modeling as foundations for creating robust and adaptable engineering models. Through progressively structured tutorials, students develop skills in part modeling, assemblies, engineering drawings, mechanism design, simulation, and manufacturing. The text incorporates real-world engineering components and workflows, including structural and thermal analysis, motion simulation, and toolpath generation, reflecting modern engineering practice. Designed for upper-division undergraduate and graduate students, this open educational resource supports hands-on learning and prepares students for industry-relevant …

Aquaculture Ecosystem Modeling Aeration Efficiency Optimization Using Cfd, Gabriela Reyes Gomez

Electronic Theses and Dissertations 2020 - Present

The Harbor Branch Oceanographic Institute (HBOI) is developing the Intelligent and Resource Efficient Pond Aquaculture (IREPA) project, which aims to improve aquaculture management through the integration of predictive models and automated technologies. This approach seeks to transition traditional practices toward data-driven systems capable of supporting informed decision-making for aeration management.

This study investigates the effectiveness of different aerator configurations on hydrodynamic circulation and dissolved oxygen (DO) distribution in aquaculture ponds using computational fluid dynamics (CFD). A model was developed in ANSYS Fluent, where the aerator was represented using a power-based formulation and implemented as a moving wall boundary condition. Dissolved …

Ais26s: Ai In Biomedicine, Shiqian Shen

Paul English Applied Artificial Intelligence (AI) Institute Publications

This presentation explores the role of artificial intelligence in advancing biomedical research and clinical practice from the perspective of a physician-scientist. Dr. Shiqian Shen discusses current challenges in neuroscience and medicine, including limitations in human observation, data analysis, and decision-making across complex biological systems. The talk highlights how AI-driven approaches such as computer vision, neural signal processing, and large-scale data modeling can improve the understanding of disease mechanisms, enhance experimental workflows, and enable more precise, patient-centered care. Specific applications include automated classification of neural activity, behavioral analysis in animal models, and multimodal data integration. A key concept introduced is “shadow …

Portable Humidity Chamber, Calvin Wright, Ian Heilers, Sam Taylor

Honors Capstones

This engineering project, sponsored by Crandall Stats and Sensors, focuses on improving the ability to test product performance under controlled environmental conditions by designing a portable humidity chamber capable of maintaining a stable relative humidity between 20 and 80 percent with a tolerance of ±0.5 percent. Consistent humidity is crucial for evaluating how moisture influences material properties, product reliability, and long-term durability in real production environments. Because Crandall conducts testing across multiple facility locations, the chamber must also be lightweight, transportable, and easy for operators to use without specialized training. Developing such a system provides the company with a valuable …

Woodward Cuk Converter, Aditi Venkatesh, Jennifer Pereira

Honors Capstones

The purpose of this senior design project is to design and build a Cuk converter, a type of buck–boost converter. The project involves developing an analytical model and validating it through hardware testing. Cuk converters are important because they are widely used in everyday electronics, particularly in renewable energy systems such as solar power, power supplies, and electric vehicles. Their ability to increase, decrease, and reverse the polarity of voltage makes them flexible. The continuous input and output currents result in low ripple, reducing component stress and improving efficiency. To achieve these goals, simulations will be conducted using LTspice to …