Digital Commons Network^™

Innovative Analysis Of Groundwater Data For Scalable, Defensible, And Predictive Compliance, Shannon Zahuranec

World of Coal Ash Proceedings

Groundwater monitoring networks at coal combustion residual (CCR) facilities now yield dataset volumes that routinely exceed the capacity of traditional, univariate interpretation. This presentation introduces a scalable multivariate and machine learning (ML) framework that prioritizes understanding data structure before predictive models are applied. The workflow applies Principal Component Analysis and other multivariate statistics to groundwater datasets, to illustrate how unsupervised learning can rapidly reveal dominant sources and controls on impacted and unimpacted groundwater quality. The talk frames multivariate analysis as a practical portfolio management tool, emphasizing inference categories rather than concentrations or site identifiers. Fleet-scale multivariate screening offers strategic advantages …

Riki&Dolphin: Real Time Data Transmission From The Bottom Of A Cave To A Website, Luca Tringali, Giacomo Canciani Dr., Tecla Tripari, Alexander Debenjak, Caterina Bearzotti

International Journal of Speleology

Coming from over 10 years of experience in cave monitoring in northeast Italy, Gruppo Speleologico Talpe del Carso, has designed Riki and Dolphin: customizable, low cost, and easy to assemble tools for getting real time data transmission from the bottom of a cave, even underwater, to a webserver. Their use has been tested to monitor air temperature inside the Abisso Bonetti Cave (Classical Karst, Italy), proving for the first time that a cave in Gorizian Karst can systematically be colder than the outdoor temperature even in winter, recording an internal temperature even lower than 0°C. The Dolphin device can be …

A Remote Sensing Approach To Identifying Zones Of Instability In Mine Tailings Impoundments Using Multi-Sensor Satellite Data, Arden K. Pierce

Honors Theses

Mine tailings impoundments are structures built to contain the chemical and sedimentary byproducts generated by ore extraction activities. In this common method of mining waste storage, the tailings can be pumped into containment ponds and held behind earthen embankments to prevent the release of hazardous substances into the surrounding environment. Monitoring environmental factors that influence the structural integrity of these impoundments is essential for identifying areas vulnerable to instability and failure. Soil moisture is a factor that can affect the stability of mine tailings impoundment structures. This study evaluates the relationship between satellite-derived soil moisture and surface deformation at mine …

Revolutionizing Closure Systems: The Performance Advantages Of Structured Geomembranes, Scott Perugia

World of Coal Ash Proceedings

Coal combustion residual (CCR) containment facilities have traditionally been closed using methods that have changed little over several decades, but structured geomembranes are now reshaping closure design by improving slope stability, increasing interface friction, enhancing drainage, and providing long-term durability. Two systems are emerging as leading solutions: a structured geomembrane paired with a geotextile and vegetative cover, and a structured geomembrane paired with engineered turf. This presentation compares these approaches using field performance data, laboratory testing, and lessons learned, with emphasis on key factors such as infiltration control, drainage efficiency, slope stability, constructability, and regulatory compliance. The engineered turf system …

From Clogs To Compliance: Overcoming Persistent Leachate Head Issues In Ccr Landfills, Breanne Kahnk, Zachary Bauman

World of Coal Ash Proceedings

State and federal regulations require that landfills, including coal combustion residual (CCR) landfills, be designed and operated to maintain leachate head levels of less than 30 centimeters (approximately 1 foot). While proper leachate collection system design and routine maintenance are critical for meeting this requirement, challenges such as clogging of drainage media, pipes, fittings and/or pipeline perforations, settlement of collection pipes, and breaks in the piping system can lead to elevated leachate levels, posing risks to compliance and long-term system performance. TRC will provide an overview of leachate collection system regulatory requirements along with design, operation, and maintenance strategies that …

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 …

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 …

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, …

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 …

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 …

Re: Conditional Approval Letter For Draft Final Silver Bow Creek Conservation Area Materials Management Plan Revision 1 (Dated March 24, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Conditional Approval Letter For Final Silver Bow Creek Conservation Area (Sbcca) Construction Quality Assurance Plan And Draft Final Silver Bow Creek Conservation Area (Sbcca) Construction Monitoring Quality Assurance Project Plan (Dated April 7, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Environmental Sustainability Assessment Of Field Phosphate Monitoring Methods For Creeks, Quintino Medi

All Theses

Creeks serve as conduits for water, nutrients, and contaminants to larger water bodies such as rivers and lakes, and their health is a key indicator of overall watershed water quality condition. Unlike rivers, creeks are under-monitored due to their small size, hydrological variability, and limited accessibility. Many technologies exist for monitoring phosphorus in surface waters. Technologies may be classified into two general categories: i) proxy real-time sensors, which record generic water quality parameters, and ii) chemical reagent-based assays, which quantify soluble reactive phosphorus (SRP) in batch samples. There is a lack of studies that compare the features and benefits of …

Optimization Of The Baffle Geometry Of A Circular Culvert Outlet Structure To Maximize Energy Dissipation, Kiarash Shirmahi

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

High-velocity flow at culvert outlets can lead to significant soil erosion and damage to downstream infrastructure, particularly in agricultural regions where land protection is critical. Circular culverts, commonly used in transportation systems, are especially susceptible to this issue due to flow acceleration caused by geometric constraints and installation angles. Despite extensive research on energy dissipation in rectangular culverts, limited attention has been given to circular configurations. This study addresses this gap by evaluating the hydraulic performance of baffle systems designed to reduce outlet energy in circular culverts.

A series of laboratory experiments was conducted using a scaled physical model of …

Urban Heat Mitigation In Newark, New Jersey Using Remote Sensing And Spatial Analysis, Ama Akowa Rhule

Theses, Dissertations and Culminating Projects

This study examines urban heat patterns in Newark, New Jersey, using remote sensing and spatial analytics to support targeted mitigation strategies. Land Surface Temperature (LST) was derived from a Landsat 8 Operational Land Imager/Thermal Infrared Sensor (OLI/TIRS) scene acquired on July 28, 2025, representing a summer snapshot of surface thermal conditions. While urban heat island effects are typically considered long-term climatic phenomena, this study uses a single-date observation to capture spatial variability in temperature across the city. Land cover variables, including tree canopy and impervious surface fractions, were obtained from the National Land Cover Database (NLCD), and demographic variables, including …

Effects Of Beaver Dams On Components Of Riverscape Health And Biodiversity In The Great Basin, Cashe C. Rasmussen

All Graduate Theses and Dissertations, Fall 2023 to Present

Networks of rivers and their floodplains (i.e., low-lying areas adjacent to rivers and streams that could plausibly flood) have been degraded, reducing the availability of freshwater and habitat for people and wildlife. Therefore, land managers are pursuing cost-effective restoration strategies, including partnering with beavers (Castor canadensis), to promote the health of these ecosystems and associated benefits. However, our understanding of beaver-mediated restoration benefits remains incomplete. Here, we compared locations along streams with and without beaver dams to measure the benefits of beavers in the Great Basin of the Western United States. We measured the effects of beaver dams …

A Spatial Analysis Of Socioeconomic Characteristics And Community Vulnerability To Natural Hazards In Arkansas, Emma Steuber, Brad Peter

Geosciences Undergraduate Honors Theses

Natural hazards have become more frequent in recent years, and because of their destructive impacts, it is crucial to locate regions that are most affected historically by hazardous events and identify what socioeconomic characteristics co-occur spatially. While many studies have analyzed this relationship at national and state scales, few have focused specifically on Arkansas, and even fewer have incorporated multiple socioeconomic characteristics. Comparing the spatial distribution of community characteristics in Arkansas with zones of common natural hazards is essential for identifying who is most at risk. This study utilizes Geographic Information Science (GISci) to examine and map the spatial relationship …

2026 Workshop On Bridging The Gaps: Tackling Microplastics And Nanoplastics Challenges In Coastal Ecosystems, Shenghua Wu, Kaushik Venkiteshwaran, Melike Dizbay-Onat, Alexandra Stenson, Jinhui Wang, Tina Miller-Way, Ebenezer Nyadjro, Bhuvnesh Bharti, John Weinstein, Yi Bao, Shihui Shen, Valerie Longa, Shenghua Zha, John Cleary, Marty Lind

Workshops

This report presents the findings from the 2026 Workshop on Tackling Microplastics and Nanoplastics (MNPs) in Coastal Ecosystems, which took place in Mobile, Alabama. More than 140 experts from universities, government, industry, and community organizations gathered to address the increasing issue of MNPs in coastal regions.

Sustainability Savvy: The Role Of Competence And Efficacy In Promoting Pro-Environmental Behavior, Lorenna Graham

Environmental Studies Honors Projects

Combatting environmental issues requires both large-scale and individual change. While many understand that personal pro-environmental behavior (PEB) is necessary, individuals do not always engage in this behavior (Hines, 1986, Goh, 2022). Thus, there is a need to investigate psychological factors which encourage PEB. Prior research suggests competence and outcome efficacy as likely PEB predictors (Bentler, 2023, Lavergne & Pelletier, 2015, Priolo, 2016), while cognitive dissonance has been shown to both encourage and discourage PEB (Bouwman, 2022, Dickerson, 1992, Ehrich & Irwin, 2005). Study 1 investigates the relationship between cognitive dissonance and PEB with competence and outcome efficacy as potential moderators. …

Model Stormwater Standards 2026, Unh Stormwater Center

UNH Stormwater Center

The purpose of post-construction stormwater management standards is to provide reasonable guidance for the regulation of stormwater runoff to protect local natural resources from degradation and prevent adverse impacts to adjacent and downstream land, property, facilities, and infrastructure. These standards regulate discharges from stormwater and runoff from land development projects and other construction activities to control and minimize increases in stormwater runoff rates and volumes, soil erosion, stream channel erosion, and nonpoint source pollution associated with stormwater runoff.

Evaluating The Effects Of Urbanization On Meiofauna Biodiversity In Chattanooga’S Lentic Ecosystems Through Gis Applications, Keyle M. Bryant

Honors Theses

Urbanization is a leading driver of biodiversity loss in freshwater ecosystems, yet its effects on meiofauna—microscopic invertebrates that serve as key bioindicators of ecosystem health—remain poorly understood in lentic environments. This study evaluated the effects of urbanization on meiofaunal biodiversity in ten lentic waterbodies across Hamilton County, Chattanooga, Tennessee, by integrating environmental DNA (eDNA) metabarcoding, in-situ abiotic measurements, and Geographic Information Systems (GIS)-based land use analysis. Water samples were collected between January and April 2023 and processed using 18S rRNA amplicon sequencing to assess biodiversity as richness (amplicon sequence variants or ASVs, phylogenetic diversity or PD, and community composition). Land …

Population Structure And Connectivity Of Atlantic Nurse Sharks (Ginglymostoma Cirratum) In The Bahamas And Outlying Areas, Baylie A. Fadool

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding animal ecosystem dynamics and behavior at the individual and population levels is essential for identifying life-history patterns and important areas for management and conservation. Marine fish species often face minimal geographic barriers to movement, but environmental (temperature, salinity, current) or intrinsic barriers (philopatry, site fidelity) can dictate gene flow. Atlantic nurse sharks (Ginglymostoma cirratum) are an International Union for Conservation of Nature (IUCN) listed ‘vulnerable’ species and present a unique opportunity to investigate patterns of population structure and connectivity in large-bodied sharks. They are benthic and display reproductive philopatry, with recent work suggesting they have the capacity …

Examining Extremes: A Comparison Between Machine Learning Based Southwestern Conus Seasonal Drought And High Fire Risk Event Synoptic Climatologies, Ethan M. Greenberg

School of Natural Resources: Dissertations, Theses, and Student Research

The Southwestern United States (SW CONUS), comprised of California, Arizona, Nevada, and Utah, is a vast region that tens of millions of people call home. Hosting ecosystems ranging from grasslands and shrublands to temperate forests and climate zones ranging from Mediterranean climates to arid deserts, the region is nearly unanimously prone to intense droughts and devastating wildfires. While fire weather conditions and drought are often studied separately or mentioned as background conditions for the other, there are relatively few studies that compare the typical meteorological conditions between the two. This study aims to more closely understand the meteorological relationship between …

Gaining Mussel: Evaluating Reintroduction Success Of Native Freshwater Mussels In Nebraska And Eastern Wyoming, Travis A. Moore

School of Natural Resources: Dissertations, Theses, and Student Research

Freshwater mussels are one of the most imperiled groups of organisms in North America, with over two-thirds of species considered threatened, endangered, or of special concern. These long-lived bivalves are essential to stream ecosystems, acting as filter feeders that improve water quality and as indicators of aquatic health. In Nebraska and Wyoming, native mussel populations have declined sharply due to habitat modification, pollution, and reduced connectivity. Two species of particular concern are the Plain Pocketbook Lampsilis cardium, listed as Tier I at-risk in Nebraska, and the Fatmucket Lampsilis siliquoidea, a Tier II at-risk species. In response, state agencies …

Assessing Water Quality And Nitrogen Dynamics In Bahia Grande, Texas Using Field And Remote Sensing Data, Sk Taufiqul Islam

Theses and Dissertations

An 8,220-acre estuary in South Texas, Bahia Grande has recently been restored from a disconnected hypersaline basin to a tidal estuary. A spatially explicit water quality index (WQI) was developed and in situ physicochemical data coupled with remote sensing data from Sentinel-2 were used to determine ecological integrity. A WQI from 29.45-53.20 yielded a spatial distribution of water quality that displayed a non-linear spatial trend throughout the estuary. Water quality close to the Brownsville Ship Channel inlet yielded values of 'Moderate/Stressed' water quality (> 50). These areas represent local zones of disturbance where ammonium concentrations were more than 11 µmol/L. …

On The Paleontology Of Belize, Alson Ovando

Electronic Theses and Dissertations

Paleontology can be considered an underrepresented and emerging area of science in Belize. A primary aim of this thesis is to provide a background of paleontology in Belize and present the first comprehensive study of Quaternary vertebrate fossils known from the country. Quaternary fossil sites across Belize include caves, rivers, and sinkholes. In addition to reviewing and assessing material from known sites, this thesis presents new information and discoveries that were made while investigating Belize’s Quaternary fossil record. This thesis also includes a geospatial model depicting ecoregions in Belize during the last glacial maximum. Overall, the results presented here demonstrate …

Redeveloping Mississippi: A Case Study On Brownfields In Central & Southern Mississippi, Sahrah R. Yeroozedek

Master's Theses

Brownfields, or properties that are or possibly are contaminated with dangerous materials, represent a common obstacle for communities in Mississippi. The real or potential presence of contaminants at these sites often deters investors due to costly cleanup requirements (EPA, n.d. -b). The Environmental Protection Agency (EPA), through its Brownfield Revitalization Program, implemented guidelines for covering the costs and labor associated with the remediation of these properties. The EPA is not, however, responsible for redevelopment that supports long-term environmental and economic sustainability. Although the EPA maintains inventories of all Brownfields, there is also no comprehensive database of Brownfields and their current …

Detecting Sophisticated Cyberattacks On Public Water Infrastructure, Ayrton Purdy

Graduate Theses and Dissertations (2019 - present)

In recent years there has been an increasing number of cyberattacks on public water generation and distribution systems. Advanced persistent attackers could usurp sensors and control systems to contaminate public drinking water. In order to conceal their malicious activity, they can manipulate sensor data flows to give the appearance of normal activity. The compromised sensors would report normal chemical levels even though unsafe water is entering the distribution system. In response, this research proposes a multi-sensor, cross-comparison approach to anomaly detection. The proposed approach is designed to detect sophisticated cyberattacks which are not easily detectable using traditional cyber tools. The …

Comparing Awssi And Traditional Winter Metrics For Predicting Overwinter Survival Of Juvenile Walleye (Sander Vitreus), Camille N. Shifrin

Honors Program: Senior Projects (Public)

Winter conditions are an important driver of recruitment variability in freshwater fishes, yet winter severity is often characterized using single climate metrics. These simplified approaches may not capture the cumulative stress experienced by fishes during winter. The Accumulated Winter Season Severity Index (AWSSI) integrates multiple components of winter climate and may therefore provide a more biologically relevant indicator of overwinter survival. In this study, we compared AWSSI with traditional winter severity metrics to explain interannual variation in overwinter survival of juvenile Walleye (Sander vitreus) in Harlan County Reservoir, Nebraska. Model comparisons using Akaike’s Information Criterion (AIC) indicated that …