Digital Commons Network^™

Re: Comment Letter For Old Butte Silver Bow Landfill/Clark Tailings Consolidated Waste Management Area (Ctcwma) Remedy Effectiveness Evaluation Phase I (Conceptual Site Model) (Dated February 27, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Butte Priority Soils Operable Unit (Bpsou) 2026 Monthly Progress Report. Consent Decree For The Butte Priority Soils Operable Unit. Civil Action No. Cv 89-039-Bu-Seh, Josh Bryson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Conditional Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Clark Tailings Consolidated Waste Management Area (Ctcwma) Site Investigation Quality Assurance Project Plan (Qapp) (Dated April 16, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Draft Final Butte Mine Waste Repository Operation And Maintenance (O&M) Plan, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Integrating Advanced Geochemical Workflows With Modern Statistical Tools To Improve The Decision-Making Process At Ccr Sites, A Case Study, Glenna Thomas

World of Coal Ash Proceedings

While statistical assessment provides the foundation for CCR compliance reporting, incorporating a holistic geochemical framework transforms statistics from a compliance requirement into a powerful predictive tool. Strategic geochemical insight established the basis of understanding needed to support successful statistical approaches and to ensure that statistical outcomes reflect actual groundwater behavior. Whether it is trend analysis, delineating source mechanism, or updating geochemical conceptual site models (GCMs), geochemical context provides the technical foundations for statistical outputs and methods. A continuously refined GCSM enhances the ability to anticipate how groundwater chemistry should evolve, improving interpretation and predictive capability. This allows practitioners to understand …

Before The Limit Hits: Lessons From A Proactive Construction Air Monitoring Program, Brian Egan, Nicholas Golden, Wendy Depp

World of Coal Ash Proceedings

This presentation describes a comprehensive air monitoring program designed to protect workers and nearby neighborhoods during ash pond closure work. The program uses three main components: project (or boundary) monitoring at the site perimeter to track dust near the project boundaries, work area monitoring placed near active construction zones, and personal sampling on individual workers at regular intervals. Together, these approaches provide data on both community impacts and worker exposures, helping the team respond quickly when levels approach action limits. The Teams actions prior to exceedance of regulatory limits has helped prevent exposures. The talk will explain how monitors are …

Lessons Learned: Commissioning An Fgd Wastewater Treatment System, Bella Triolet, Mckale Grant, Louis Manigault

World of Coal Ash Proceedings

Stantec recently supported commissioning a flue gas desulfurization (FGD) Wastewater Treatment System in accordance with the 2020 Environmental Protection Agency (EPA) Effluent Limitations Guidelines (ELG) Rule, which requires that coal fired power plants meet their more stringent requirements by December 31, 2025. With the addition of the 2024 EPA ELG Rule, coal fired power plants will now be expected to move to zero liquid discharge (ZLD) systems or permanently cease coal combustion by 2034. Due to this change, it is likely that coal fired power plants will be looking to design and install ZLD systems within the next decade. While …

Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Quarterly Operation And Maintenance Report: Butte Treatment Lagoons (Btl) System– Fourth Quarter 2025 (Dated March 30, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Dissecting The Connection Between Technological Advancement And Environmental Justice Through An International Perspective, Benson H. Le

Honors Theses

This thesis dissects the connection between technological advancement and environmental justice through an international perspective. With modern-day technologies advancing by the day, the implications of these technologies on our environment have been rising as well. This thesis looks to dissect the connection between these two entities, as well as view this connection through an international lens. Countries around the world view this connection very differently, and the way these technologies are implemented within the environment is drastically different based on different international views. This thesis aims to answer the questions about this phenomenon. How do countries around the world view …

Re: Conditional Approval Letter For Draft Final 2026 Interim Site-Wide Groundwater Monitoring Quality Assurance Project Plan (Dated May 6, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

A Novel Geospatial Tool For Assessing Risks And Opportunities For Conversion Of Ccr Closures Into Productive Solar Energy Generation Sites, Marc Theisen

World of Coal Ash Proceedings

Closure of Coal Combustion Residuals (CCR) surface impoundments and landfills offers unique opportunities for conversion to solar power sites with the potential to offset costs of post-closure care via generation of clean electricity. In 2023 the US Environmental Protection Agency (EPA) collaborated with the National Renewable Energy Laboratory (NREL) to create a report entitled “Coal Ash Disposal Sites and Opportunities for Solar Photovoltaic Development” (EPA Publication #540-S-23-004). The purpose of this document was to identify closed CCR units and provide key factors for their potential for solar photovoltaic (PV) development. In 2022, the EPA’s RE-Powering Initiative identified 772 current CCR …

Establishing Sustainable Vegetation On A Challenging Legacy Ccr Site, Derek Oosterhouse, Blake Arthur

World of Coal Ash Proceedings

American Electric Power (AEP) is closing and restoring a legacy Coal Combustion Residuals (CCR) site in Ohio that once held a power plant that pioneered innovative steam generation technology. The plant was closed in 1975. Today, the legacy CCR site is being transformed back to natural, sustainable vegetation. To comply with and close the Stormwater Pollution Prevention Plan (SWPPP) permit, permanent stabilization is required on the site. AEP, one of the largest electric companies in the country, holds a core principle to respect the environment through creative sustainable solutions. AEP connected with Profile Products, the world’s largest manufacturer and supplier …

Future Strategies For Beneficial Use Harvesting, Gabe Lang, Patrick Kiser

World of Coal Ash Proceedings

TVA is the largest public power company in the U.S. and has historically operated a fleet of 12 coal-fired plants as part of their diverse generating portfolio. To date, eight of the coal plants have been retired and the remaining four plants are projected to shut down in the next couple of decades. The decommissioning of these plants is driving a transition to harvesting of ponded and landfilled CCR’s to continue to support ready-mix concrete and other industries that enable infrastructure development. However, the regional market demand limits the ability to initiate widespread harvesting activities during near-term CCR Unit closure …

Methods To Enhance Groundwater Remediation During Cbr And Mass Transfer Controls On Post-Closure Groundwater Cleanup At Ccr Impoundments, Sean Larkin, Jacob Chu, John Blue

World of Coal Ash Proceedings

Utilities are implementing closure‑by‑removal (CBR) of coal combustion residual (CCR) impoundments as part of corrective action programs to meet groundwater protection standards (GWPSs) and are evaluating closure strategies for Legacy Units. Although CBR and associated decanting and dewatering systems can substantially reduce source mass and improve groundwater quality, lingering “tail” concentrations in the aquifer are often observed after closure because groundwater remediation typically requires extended timeframes. These persistent concentrations may be compounded by secondary source zones beneath the former impoundment, where constituent mass stored in low‑permeability materials or immobile pore spaces is slowly released into the transmissive aquifer after CBR. …

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. …

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 …

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. …

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 …

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 …

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 …

Air Quality, Atmospheric Pressure, And Migraine Presentations In The Emergency Department, James Espinosa, Alan Lucerna

Rowan-Virtua Research Day

Background: Migraine is a leading cause of Emergency Department (ED) visits and global disability. Weather has long been reported by patients as a trigger, yet the literature remains inconsistent. Prior ED-based data demonstrated an association between higher mean barometric pressure and increased migraine presentations, without a relationship to short-term pressure change. Because high-pressure systems are frequently associated with atmospheric stagnation and pollutant accumulation, air quality may represent a biologically plausible mediator.

Objective: To examine the relationship between air quality and ED migraine presentations within the existing body of literature and to explore whether air quality may help explain previously observed …

Listening To The System: Reframing Emergency Department Noise: The Case For Noise As A Real-Time Operational Signal In A Complex Adaptive System (Cas), James Espinosa, Alan Lucerna, Henry Schuitema

Rowan-Virtua Research Day

Emergency Department (ED) noise has historically been framed as an occupational and environmental hazard requiring mitigation. And this is still true—but not complete. Early work focused on exposure reduction and spike identification. Subsequent mapping studies demonstrated spatial and temporal differentiation in ED acoustic load. We propose an expanded conceptual model: acoustic variability may function not only as a hazard, but also as a real-time signal of operational turbulence within the ED as a complex adaptive system (CAS). Drawing on human factors, alarm fatigue, resilience engineering, and complexity science, we synthesize existing literature and institutional experience to identify a critical gap—noise …

Plasma Coal Ash Processing For Enhanced Recovery Of Rare Earth Elements & Precious Metals: Proven From R&D To Commercial Plants, George Paskalov, Victoria Campbell, Jason Honigberg

World of Coal Ash Proceedings

Our Radio-frequency Plasma System is an ash pretreatment before the application of extractive metallurgy and addresses current elemental, methodological, and technological limitations of complex and refractory coal ash. Our system data shows from 10-20% improved recovery, to 9x-100x. RFP can access all metals contained in coal ash. Our focus is not on the alteration of established methodologies, such as cyanidation for non-refractory ore, which has a proven return and capacity to achieve target revenue at-scale. Using the RFP systems, no waste is created, overburden can be more easily dealt with, and no metal content will be left behind. We assert …

Standardization Of Coal Ash Testing, Classification, And Harvesting, Benjamin Gallagher, Chris Frishcosy, Eric Hageman

World of Coal Ash Proceedings

Standards such as product specifications, test methods, practices and guides play a crucial role in supporting both commerce and science. Standardization helps build consistency and reliability whether it pertains to the performance of an ingredient in a product or in the measurement of a material characteristic. Coal combustion products, such as coal ash and synthetic gypsum, exhibit unique characteristics and many standard have been developed to characterize these materials and support their beneficial use. ASTM is a voluntary, consensus-based organization, and publishes many standards related to coal combustion products. Currently, there are seven ASTM standards related to chemical analysis of …

Impacts Of Updating Background Groundwater Statistics For Ccr Compliance, May Raad, Molly Reeves

World of Coal Ash Proceedings

In 2017, many power utilities adopted statistical methods to comply with the EPA’s Coal Combustion Residuals (CCR) Rule under the Hazardous and Solid Waste Management System. By 2017–2018, most owners completed initial statistical evaluations for detection and assessment monitoring to meet CCR deadlines. Groundwater sampling and analysis requirements in Parts 257.95, 257.98, and 257.102 are critical for compliance, yet implementation is complex. Subsections 257.93(f) and (g) lack clarity on which statistical tests to apply or how to address distributions and outliers. Additionally, the Rule does not specify when or how to update background threshold values (BTVs), though EPA’s Unified Guidance …

Advancing Ccr Site Management With Rapidly Deployable Gccm Technology For Runoff And Drainage Control, Nathan Ivy

World of Coal Ash Proceedings

GCCM’s were first invented over 20 years ago. These products combine both a concrete – hard armor – top surface for protection and durability and a geomembrane bottom surface for lower permeability. Originally used for erosion control, smaller drainage channel and remediation projects, this presentation discusses the newest iteration in GCCM technology. This product incorporates a 12 mil LLDPE backing which allows for thermal bonding and significant reduction in seepage at the joints. It can be used in a wide variety of applications from drainage ditches and swales to water and wastewater conveyance along with slope protection and erosion control …

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 …

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 In The Fashion Industry: Environmental Effects & Analyzing Innovative Approaches To Reducing Environmental Impact While Maintaining Profitability And Effectiveness, Haley Castillo Rebollar

Senior Honors Theses

The fast-fashion business model has several severe environmental impacts, including resource overconsumption, chemical pollution, greenhouse gas emissions, and solid waste consumption. Hence, the sustainable fashion alternative is questioned as to whether it can be applied with recoverable economic value and limited consequential impact when considering novel approaches in business model innovation, supply chain transformation, and the adoption of digital technologies. Evidence suggests that sustainability and profitability need not be mutually exclusive when strategic intervening actions are effectively managed. The set of principles of the circular economy, sustainable enterprise architecture frameworks, green supply chain management, advanced systems of forecasting, and three-dimensional …

Pest Risk Modelling For Climate-Smart Vegetable Production In East Africa, Marc Marin Agbodjan, Komi Mensah Agboka, John Odindi, Elfatih Abdel-Rahman, Onisimo Mutanga, Frank Chidawanyika, Chrysantus Tanga, Daniel Munyao Mutyambai, Sevgan Subramanian, Bonoukpoè Mawuko Sokame

All Peer-Reviewed Publications

Agricultural productivity in East Africa is increasingly threatened by climate-sensitive insect pests. This study investigates the occurrence of key vegetable pests: Brevicoryne brassicae, Plutella xylostella, Maruca vitrata, and Liriomyza mik. A comparative species distribution modelling evaluated pest risk projections under climate change. Four variable selection strategies were tested: case 1 (correlation and variance inflation factor [VIF] filtering across all predictors), case 2 (correlation and VIF filtering of bioclimatic variables merged with other predictors), case 3 (filtering based on environmental values at species occurrence point to approximate realized niches), and case 4 (dimensionality reduction using principal component analysis). These strategies were …