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Environmental Indicators and Impact Assessment

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Full-Text Articles in Oil, Gas, and Energy

Engineered Turf And Solar Renewable Performance On Ccr In Extreme Weather, Tate Niekamp, Bryan Scholl, Ming Zhu, Thomas Orzech May 2026

Engineered Turf And Solar Renewable Performance On Ccr In Extreme Weather, Tate Niekamp, Bryan Scholl, Ming Zhu, Thomas Orzech

World of Coal Ash Proceedings

The engineered turf final closure system, ClosureTurf®, is installed on a 309-acre coal combustion residual (CCR) unit at the TVA Shawnee Fossil Plant in West Paducah, KY. Approximately 100 megawatts of the PowerCap® solar photovoltaic (PV) system is currently being deployed directly atop the engineered turf cover. An overview of the ClosureTurf® and PowerCap® systems are presented along with a comparison to traditional soil covers and conventional utility-scale solar arrays. From August 2023 through July 2025, onsite and local weather data stations reported over 20 storm events including severe thunderstorms, tornado outbreaks, winter storm systems, atmospheric rivers, and post-tropical cyclones. …

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A Cost-Effective, Low-Impact Remedial Approach For Metals: Utilizing Phyto-Enhancement To Accelerate Ph Adjustment Of Shallow Groundwater, Jerry Wylie, Thomas Colton May 2026

A Cost-Effective, Low-Impact Remedial Approach For Metals: Utilizing Phyto-Enhancement To Accelerate Ph Adjustment Of Shallow Groundwater, Jerry Wylie, Thomas Colton

World of Coal Ash Proceedings

SynTerra will present a unique, low-cost, low-impact approach to metals remediation in shallow groundwater at a former industrial site located in the Atlantic Coastal Plain. The approach employs pH adjustment of groundwater using agricultural lime coupled with the use of daikon radish to augment lime contact time and to increase depth of soil augmentation. This method is designed to be a more sustainable, less resource-intensive, and less technically challenging remedial alternative with lower estimated overall costs. The primary corrective action—source removal—has been completed. However, the oxidation of residual sulfide-bearing minerals has resulted in persistent low-pH groundwater, which increases the solubility …

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The Effect Of Closure In Place On Groundwater Performance Objectives, Dennis Connair, Jason Lach, Rachel Bosch May 2026

The Effect Of Closure In Place On Groundwater Performance Objectives, Dennis Connair, Jason Lach, Rachel Bosch

World of Coal Ash Proceedings

The effect of closure in place (CiP) of a coal combustion residual (CCR) surface impoundment on the achievement of groundwater remedial performance objectives is evidenced in groundwater monitoring data. The CCR unit is located over a major alluvial aquifer adjacent to a navigable river. The unit is separated from the aquifer by an unsaturated zone and the compliance monitoring wells are located at the unit boundary. Sluicing of CCR to the unit was ceased in early 2020 with dry placement of CCR from other units and CiP/installation of a composite cap substantially completed by the end of 2020. Groundwater corrective …

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Innovations To Engineered Synthetic Turf Solutions For Ccr Units, Nicholas Golden, Gabe Lang, Bradford Cooley May 2026

Innovations To Engineered Synthetic Turf Solutions For Ccr Units, Nicholas Golden, Gabe Lang, Bradford Cooley

World of Coal Ash Proceedings

The use of engineered synthetic turf cover systems (e.g. ClosureTurf®) and hydraulic revetment systems (e.g. HydroTurf®) has been increasing on CCR units across the US. In the past 15 years, these systems have been installed on more than 500 combined projects totaling over 5,000 acres. The extensive use of these systems has resulted in continued research and development to address challenging site conditions by improving performance, enhancing extreme event resilience, and reducing maintenance. This presentation will focus on three specific innovations that have been developed to address site specific challenges associated with CCR units. Specifically, two new innovative engineered synthetic …

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Integrated Groundwater Flow And Transport Modeling For Coal Combustion Residual (Ccr) Sites: From Closure Permitting To Corrective Action, Brian Hennings, Pejman Rasouli, Vic Modeer, Rhys Fuller May 2026

Integrated Groundwater Flow And Transport Modeling For Coal Combustion Residual (Ccr) Sites: From Closure Permitting To Corrective Action, Brian Hennings, Pejman Rasouli, Vic Modeer, Rhys Fuller

World of Coal Ash Proceedings

This session describes a coordinated multi-year effort to assess and manage groundwater quality at five CCR impoundments. The objectives were to (i) develop site-specific hydrogeologic and geochemical conceptual models; (ii) quantify groundwater flow and constituent transport under baseline and post-closure conditions; and (iii) design and evaluate corrective action strategies that achieve regulatory compliance and provide a defensible framework for long-term monitoring and management. The program highlights a phased approach aligned with regulatory requirements, progressing from closure construction to corrective action planning for detected exceedances. Comprehensive hydrogeologic datasets including borehole lithology, hydraulic testing, CCR source water characterization, and groundwater monitoring were …

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Improving Economic And Environmental Outcomes Of Legacy Coal Ash Ponds, Grace Wilken May 2026

Improving Economic And Environmental Outcomes Of Legacy Coal Ash Ponds, Grace Wilken

World of Coal Ash Proceedings

This project demonstrates a novel approach to utilize legacy coal ash waste ponds by processing the solids for use in cement/concrete and bioremediating the water fraction through algae cultivation. The algal biomass can then be used for animal feed, biofuels, or other valuable bio-products. There is an increasing demand for more environmentally friendly and cost-effective materials for concrete production, such as coal fly ash, yet a decreasing supply of ash as coal power plants are decommissioned in the transition to other energy sources. However, there are billions of tons of coal ash accumulated in legacy ash ponds across the US. …

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High Ccp Utilisation In Road Repairs: Demonstration, Monitoring And Outcomes For State Road Authorities In Australia, Craig Heidrich, Jodi Milne, Ashnik Nanoo, Geoff Hines May 2026

High Ccp Utilisation In Road Repairs: Demonstration, Monitoring And Outcomes For State Road Authorities In Australia, Craig Heidrich, Jodi Milne, Ashnik Nanoo, Geoff Hines

World of Coal Ash Proceedings

The increasing demand for sustainable construction materials as well as decarbonising the power industry has driven research into alternative road and pavement construction methods. One such alternative, available in significant volumes, is coal combustion products (CCPs), which can reduce environmental impact and preserve natural resources while maintaining or improving performance characteristics. This paper presents the outcomes of a multi-year, full-scale road repair trial at Stanwell Power Station, approximately 30 km southwest of Rockhampton in Queensland. The trial was designed to rigorously assess the performance of experimental flexible and rigid pavements, containing significant amounts of CCPs in various structural layers, against …

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Navigating Regulatory Uncertainty In Ccr Management: A Panel Discussion, Mark Rokoff, Richard Huggins, Martha Thomsen, Roger Clarke May 2026

Navigating Regulatory Uncertainty In Ccr Management: A Panel Discussion, Mark Rokoff, Richard Huggins, Martha Thomsen, Roger Clarke

World of Coal Ash Proceedings

The only certainty in CCR management is regulatory uncertainty! As we approach 2026, the industry and “CCR Universe” faces significant challenges and uncertainties due to the proposed EPA rule expected early in the year. This panel discussion will bring together a diverse group of industry experts, including representatives from associations (e.g. EEI), legal professionals, utility representatives, and consultants, to address the hard questions head-on and provide insight to and understanding of the implications of these regulatory changes. Key discussion points will include: • Legal Ramifications and Possible Pathways for 2026: Exploring the potential major pathways considering the proposed regulations and …

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Coal Combustion Residual Impoundment Closure And Capping Impacts To Groundwater, Danielle Sylvia Cofelice, Thomas Haskins May 2026

Coal Combustion Residual Impoundment Closure And Capping Impacts To Groundwater, Danielle Sylvia Cofelice, Thomas Haskins

World of Coal Ash Proceedings

Closure of coal combustion residual (CCR) impoundments is a critical step in mitigating long-term environmental risks, particularly to groundwater quality. This presentation evaluates spatial and temporal behavior of key groundwater contaminants during and following closure that included excavation and capping of CCR impoundments at one coal fired electric generating facility. The assessment integrates spatiotemporal plume mapping, plume area and concentration trend charts, and dissolved mass in place metrics to assess contaminant concentration, migration, and attenuation in post-closure environments. Observed trends include both increasing and decreasing concentrations of key constituents during and following closure activities, suggesting complex interactions involving residual CCR …

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Engineering Stormwater Resilience In Steep Valley Ccr Landfill Construction, Kevin Resnik, Grant Phelps May 2026

Engineering Stormwater Resilience In Steep Valley Ccr Landfill Construction, Kevin Resnik, Grant Phelps

World of Coal Ash Proceedings

Construction of a CCR landfill within steep geography presents unique challenges related to stormwater management, erosion control, and establishing placement and compaction practices over an extended construction timeline. This presentation builds upon prior work focused on temporary rain cover and wet-weather resiliency, expanding the discussion to practical strategies implemented during the prolonged startup and subsequent phases of waste placement. Key topics include: Stormwater management during active construction, with emphasis on intercepting, conveying, and controlling runoff in a topographically constrained setting. Breaking up drainage areas to reduce flow concentrations, prevent channelized erosion, and improve maintainability as grading evolves. Erosion control approaches …

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Rapid Field Methods To Distinguish Coal Ash And Soil, Benjamin Gallagher, Klaudio Peshtani, Lee Slater, Rebecca Kreuzer May 2026

Rapid Field Methods To Distinguish Coal Ash And Soil, Benjamin Gallagher, Klaudio Peshtani, Lee Slater, Rebecca Kreuzer

World of Coal Ash Proceedings

Some coal ashes exhibit soil-like textures and colors. If the coal ash and native soil at an impoundment or landfill site have similar appearances, it can be difficult to distinguish these materials in the field. Therefore, field and lab methods may be needed to supplement visual and manual observations. The results of a laboratory investigation of rapid screening methods (induced polarization, magnetic susceptibility, nuclear magnetic resonance, and colorimetry) for the discrimination of coal ashes and soils are discussed. Across five series of lab-created soil and coal ash mixtures, lab measurements of induced polarization and magnetic susceptibility values both showed strong …

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Corrective Action Alternative Evaluation For Surface Impoundment Remedy – Two Case Study Examples, Qian Zhang, Andrew Bittner May 2026

Corrective Action Alternative Evaluation For Surface Impoundment Remedy – Two Case Study Examples, Qian Zhang, Andrew Bittner

World of Coal Ash Proceedings

Illinois Administrative Code Part 845 requires owners and operators of coal combustion residual (CCR)-containing impoundments with groundwater protection standard (GWPS) exceedances to perform a Corrective Action Alternatives Analysis (CAAA) to evaluate viable remedies prior to selecting and implementing corrective action. The goal of a CAAA is to holistically evaluate a range of factors for the various corrective actions being considered at an impoundment. This presentation summarizes two CAAAs conducted for surface impoundments (SIs) at two power plants. Each CAAA applied a consistent decision framework that evaluates corrective action options using multiple performance criteria, such as: • Magnitude of Reduction of …

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Capping And Closure Of Two Pennsylvania Ccr Landfills: Progress Update And Key Insights, Cory White, Ron Harris, John Klamut May 2026

Capping And Closure Of Two Pennsylvania Ccr Landfills: Progress Update And Key Insights, Cory White, Ron Harris, John Klamut

World of Coal Ash Proceedings

This project consists of the ongoing capping of two, 200-acre, coal combustion residual (CCR) landfills with geosynthetic capping systems consisting of 15 to 24 inches of final cover soil over eight ounce per square yard filter/separation geotextile over Super Gripnet geomembrane with drainage studs along top and friction spikes along the bottom over a prepared subgrade consisting of in-place cover soil. Approximately 80 acres were capped at each landfill from 2023 to 2025. To comply with Title 25, Pennsylvania Code §288.234(d), requiring closure within one year after cessation of waste placement, approximately 30 acres of each 200-acre site must be …

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Tva Paf Gypsum Stack Final Closure – Lessons Learned And Planning For Future Use, Brooke Alison, Nicholas Golden, Gabe Lang, Shane Harris May 2026

Tva Paf Gypsum Stack Final Closure – Lessons Learned And Planning For Future Use, Brooke Alison, Nicholas Golden, Gabe Lang, Shane Harris

World of Coal Ash Proceedings

This case study involves review of the closure design and construction of a 250-acre gypsum stack at TVA's Paradise Fossil Plant using Watershed Geo's ClosureTurf final cap system. The design review will include the selection criteria of the final closure cap system, the use of a flatter-than-conventional 150-acre top deck grade, discussion of the storm water management strategy, and the planning for future use which potentially includes solar development and future harvesting of the CCP. Lessons learned will be presented including performance of the flat top deck, challenges associated with access roads over ClosureTurf, and geosynthetics documentation processes.

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Unlocking Data Integrity: How Historical Data Review Enhances The Accuracy Of Laboratory Results, Danielle Coles May 2026

Unlocking Data Integrity: How Historical Data Review Enhances The Accuracy Of Laboratory Results, Danielle Coles

World of Coal Ash Proceedings

Due to the implementation of the CCR rule and longstanding state regulatory guidelines, many utilities have built robust historical data sets associated with their groundwater monitoring programs. Data collected through these monitoring programs are used for many purposes including generation of statistics and site evaluation along with reporting to regulators and the public. Often, trends in data are evaluated long after data reporting to look at large scale trends or movement of constituents in the groundwater across a CCR landfill or entire site, but historical data sets can be used in real time to help determine the accuracy of current …

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Coal-Derived Fly Ash – The Outlook Is Bright In The Uk, Nigel Cooke May 2026

Coal-Derived Fly Ash – The Outlook Is Bright In The Uk, Nigel Cooke

World of Coal Ash Proceedings

The global imperative to reduce greenhouse gas emissions is reshaping industrial strategies across all sectors, with construction facing particular scrutiny due to its significant embodied carbon footprint. In response, greater emphasis is being placed on proven materials that can deliver both performance and environmental benefits. Coal-derived fly ash (CDFA) has a long and successful history within the UK construction sector. It is widely recognised for the technical advantages it brings to concrete and mortar performance, as well as its established use in applications such as autoclaved aerated concrete, grouts, and secondary aggregates. As the UK commits to achieving net-zero carbon …

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Anthropogenic Lithologic Characterization Through Use Of Advanced Visual Tools As A Means Of Identifying Coal Ash, Stephen Papageorge, Lucas Mangold May 2026

Anthropogenic Lithologic Characterization Through Use Of Advanced Visual Tools As A Means Of Identifying Coal Ash, Stephen Papageorge, Lucas Mangold

World of Coal Ash Proceedings

Identification and differentiation of particular Anthropocene strata such as coal ash and historic fill intermixed with native unconsolidated overburden presents significant challenges. To make specific determinations about origin and composition, a variety of tools are available such as our well-defined lithologic characterization processes. However, additional tools are required, as important and defining characteristic evidence isn’t available or obvious to our senses in the field. One challenge is the absence of surficial evidence of ash areas. Secondly, we are faced with limited access, as the responsible party no longer owns the site, there is new construction in the area of historic …

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Fifteen Years, 450 Acres: Inside The Tva Gallatin Ash Pond Closure, Brian Egan, Shane Harris May 2026

Fifteen Years, 450 Acres: Inside The Tva Gallatin Ash Pond Closure, Brian Egan, Shane Harris

World of Coal Ash Proceedings

This presentation is focused on the TVA Gallatin Ash Pond Complex Closure. The project team embarked on a major coal ash pond remediation effort in 2023, targeting a 450-acre site with operations expected to continue over a 15-year period. The long-term and massive scope of this dig and haul project required the design and construction of extensive supporting infrastructure, including haul roads suitable for large earthmoving equipment, major pipelines for process water rerouting, and a robust water treatment facility. Key components of the work include maintaining slope stability, conducting comprehensive air quality monitoring, and ensuring high standards for coal ash …

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Ensuring Quality Geosynthetics Installations Throughout The Project Lifecycle, Glen Toepfer May 2026

Ensuring Quality Geosynthetics Installations Throughout The Project Lifecycle, Glen Toepfer

World of Coal Ash Proceedings

Geosynthetics serve numerous functions in containment systems used within the Coal Ash Industry and ultimately protect the site owner from liability. A failure in the geosynthetics containment system exposes the owner to liability; therefore, it is imperative that these geosynthetic containment systems be installed correctly to mitigate the risk of failure. Avoiding failure is not just the responsibility of the geosynthetics installer – it is the responsibility of every party involved in the project lifecycle from conception through post-closure. In fact, the success of the field installation is largely determined before the first panel of geomembrane is ever installed. The …

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Novel Use Of Ped-Xrf For Identification Of Ccr In Fill Units And Comingled Media, Charla Barnes, Harris Byers, Eric Hageman May 2026

Novel Use Of Ped-Xrf For Identification Of Ccr In Fill Units And Comingled Media, Charla Barnes, Harris Byers, Eric Hageman

World of Coal Ash Proceedings

The EPA CCR Legacy Rule requires utilities to identify any areas of land on which noncontainerized accumulation of CCR is received, is placed, or is otherwise managed. While performing preliminary delineation efforts for implementation of the Legacy Rule, it has become apparent that not all encountered materials are easily identified through visual means. Depending on unit location, previous uses of the land underlying the potential CCR Management Units, and the type of native soils present, there may be uncertainty if an encountered material is CCR, native soil, or another non-CCR material. In cases where the color/texture of CCR fill is …

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Evaluation Of Bottom Ash For Beneficial Use, Danielle Sylvia Cofelice, Thomas Haskins May 2026

Evaluation Of Bottom Ash For Beneficial Use, Danielle Sylvia Cofelice, Thomas Haskins

World of Coal Ash Proceedings

Historically, bottom ash has been beneficially used as a drainage layer within the final cover system for a coal combustion residual (CCR) landfill, positioned above the linear low-density polyethylene liner and below the protective soil cover and topsoil layers. This sustainable approach not only diverts bottom ash from waste management streams but also conserves natural resources by replacing the need for virgin materials, resulting in significant cost savings for ratepayers. To support the continued use of bottom ash in this application, an environmental assessment was completed. The assessment included sampling of bottom ash, an alternative drainage layer composed of virgin …

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Germanium And Gallium: Evaluating Their Potential In Coal Ash, Ari Campanaro May 2026

Germanium And Gallium: Evaluating Their Potential In Coal Ash, Ari Campanaro

World of Coal Ash Proceedings

Germanium (Ge) and gallium (Ga) have been classified as critical minerals by the Department of the Interior due to their unique properties and security risk to the supply chain. Recent restrictions on Ge and Ga imports have exacerbated the need for domestic Ge and Ga from resources such as coal ash, the largest source of industrial waste in the U.S. Understanding the abundance and modes of occurrence of Ge/Ga in a specific fly ash source is essential to evaluate its feasibility as a Ge/Ga resource. Microbeam Technologies, Inc (MTI) is evaluating fly ash resources from coal combustion and gasification systems …

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Tuning Boilers To Reduce Carbon In Fly Ash - Making Salable Ash, Rod Hatt May 2026

Tuning Boilers To Reduce Carbon In Fly Ash - Making Salable Ash, Rod Hatt

World of Coal Ash Proceedings

This paper will describe various coal quality and combustion improvement facts and methods. Impact of fuel parameters like calorific value, ash, HGI, and volatile will be briefly covered. The main focus of this paper is on pulverizer performance and balancing combustion to lower carbon in fly ash. Pulverizers operating with larger than design coal particles tend to create an unbalanced pipe to pipe coal flow. This results in zones of low excess O2, even if average O2 settings are maintained. Impact on coal size and pipe balance of classifier settings and primary air flow will be covered. The importance of …

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Liquefaction Susceptibility And Brittleness Of Coal Ash - A State Parameter Approach, Suafa'i Manson, Benoit Wentzinger, Scott Lines May 2026

Liquefaction Susceptibility And Brittleness Of Coal Ash - A State Parameter Approach, Suafa'i Manson, Benoit Wentzinger, Scott Lines

World of Coal Ash Proceedings

Limited data exists on the liquefaction susceptibility of combined fly ash and bottom ash deposits. Their low plasticity and settling density pose a risk of liquefaction under certain triggers. The liquefaction potential is linked to the in-situ state, defining its shearing behaviour as dilative or contractive based on relative density and effective confining stress. This can be assessed using the state parameter (Ψ) concept from critical state soil mechanics theory. This paper presents findings from a follow-up to our 2021 study, which used cone penetration test (CPT) based methods to estimate the in-situ state parameter and perform liquefaction susceptibility screening. …

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Evaluating And Managing Ccr Variability At An Active Beneficial Use Clean Closure Site, John Garten, Bob Baker, Lee Lenhart May 2026

Evaluating And Managing Ccr Variability At An Active Beneficial Use Clean Closure Site, John Garten, Bob Baker, Lee Lenhart

World of Coal Ash Proceedings

The basin is a 132-acre (534,200 square meter) coal combustion residual (CCR) disposal impoundment that has been undergoing closure-by-removal since 2021, with CCRs harvested for use in concrete manufacturing. Excavated CCRs are processed on-site through initial drying and screening before being routed through a thermal beneficiation process. Despite an extensive pre-closure CCR characterization program, pockets of material encountered in 2025 caused significant off-specification issues for the beneficiation feedstock that required immediate corrective action. To address this, a supplemental surveying, sampling, and on-site testing program was implemented to obtain additional grainsize and Loss on Ignition (LOI) data for active and upcoming …

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Identifying And Controlling Landfill Construction Impacts To Stormwater Flow Paths, Kory Anstead May 2026

Identifying And Controlling Landfill Construction Impacts To Stormwater Flow Paths, Kory Anstead

World of Coal Ash Proceedings

This presentation will examine the engineering challenges and lessons learned associated with construction impacts and altered stormwater flow paths in the vicinity of a Sediment Pond adjacent to a newly constructed landfill. During construction activities, the sediment basin liner experienced multiple instances of flotation. Early corrective measures were implemented as quick fixes; however, these proved ineffective and ultimately necessitated more comprehensive solutions once the underlying causes were better understood. The presentation will begin with an analysis of the initial liner flotation events, focusing on the conditions that led to the problem, the immediate responses, and the eventual engineered solution. It …

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Three Use Cases For Interferometric Synthetic Aperture Radar (Insar) For Coal Ash Combustion (Ccr) Pond Closure Projects, Zach Boucias May 2026

Three Use Cases For Interferometric Synthetic Aperture Radar (Insar) For Coal Ash Combustion (Ccr) Pond Closure Projects, Zach Boucias

World of Coal Ash Proceedings

Interferometric Synthetic Aperture Radar (InSAR) is a satellite-based radar system that uses electromagnetic pulses and advanced post-processing software to detect ground subsidence across large areas with millimetric precision. This paper has two primary objectives: (1) to outline the advantages and limitations of InSAR and (2) to present three specific use cases for InSAR in connection with coal combustion residual (CCR) pond closures. InSAR offers key advantages over traditional monitoring methods: remote monitoring without field intervention, full-surface coverage, all-weather and day/night operation, and high precision. InSAR also has limitations in connection with rapidly changing surface conditions, and the presence of water …

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Carbon-Negative Supplementary Cementitious Materials Produced From High-Calcium Coal Ashes, Hongyan Ma May 2026

Carbon-Negative Supplementary Cementitious Materials Produced From High-Calcium Coal Ashes, Hongyan Ma

World of Coal Ash Proceedings

High-calcium coal ashes, traditionally considered challenging for use in blended cements, offer unique opportunities for the development of carbon-negative supplementary cementitious materials (SCMs). This study explores innovative processing and carbonation strategies to transform high-calcium ashes into reactive binders that not only reduce clinker demand but also permanently sequester CO2. Through multiple optimized and enhanced carbon mineralization pathways, the treated ashes exhibit enhanced pozzolanic performance, durability, and compatibility with Portland cement systems. Life-cycle analysis confirms that the dual benefits of CO2 capture and clinker displacement yield a net carbon-negative profile, advancing both decarbonization of cement production and sustainable coal ash management.

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Harvesting Rare Earths From Coal Ash Using An Ionic Liquid, Laura Stoy May 2026

Harvesting Rare Earths From Coal Ash Using An Ionic Liquid, Laura Stoy

World of Coal Ash Proceedings

This presentation highlights a promising early-stage pathway for transforming coal fly ash from a long-term liability into a source of both critical minerals and construction materials. The speaker describes a recyclable ionic-liquid process that, at bench scale, demonstrates selective recovery of rare earth elements (REEs) from a wide range of U.S. fly ashes under mild conditions while preserving the treated solids for potential use as supplementary cementitious materials (SCMs). Attendees gain insight into why this chemistry is attracting attention: it avoids full acid digestion, shows strong preference for REEs over bulk metals, and enables repeated solvent reuse in a closed …

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Subsurface Delineation Of Coal Combustion Residuals Using Multiple Geophysical Methods, Eric Hageman, Adam Rak, Thomas Jordan, Kate Mckinley May 2026

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 …

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