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Plenary: Mathematics Of Malaria Transmission Dynamics: The Renewed Quest For Eradication, Abba Gumel

Biology and Medicine Through Mathematics Conference

No abstract provided.

Ongoing Novel Critical Metals Recovery From Coal Ash, Claudio Arato

World of Coal Ash Proceedings

Novel Critical Metals Recovery Techniques from Coal Ash Authors Mr. Claudio Arato - Canada - SonoAsh Abstract Abstract Summary This presentation will focus on the new and emerging areas of interest for SonoAsh. While Critical metals recovery has always been part of the SonoAsh process, this presentation will specifically focus on our new, patent pending methodology to extract Lithium ions from coal ash using a proprietary membrane grafting techniques developed in collaboration with Dr. Mohamad Al-Sheikhly’s at the University of Maryland, College Park. The technology is in the state of optimization and studies are being performed to determine the maximum …

Cutoff Walls For Groundwater Containment And Corrective Action, Dale Evans, Paul Schmall, Jeff Bean

World of Coal Ash Proceedings

Cutoff Walls for Groundwater Containment and Corrective Action Authors Mr. Dale Evans - United States - RECON Dr. Paul Schmall - United States - Keller Mr. Jeff Bean - United States - Keller Abstract With years of pond closure work already completed, there is a recent shift of focus that has been drawing significant attention to perimeter groundwater barriers for corrective action or for containing deep saturated ash below historic groundwater levels. The implementation of perimeter cut-offs is particularly challenging for CCR ponds because of the lack of space outside of these sites, the sensitive environment in which this work …

Design And Commissioning Of Coal Ash Filter Plant, James Keat, Jason Hamelehle, Casey Schmitt

World of Coal Ash Proceedings

Design and commissioning of coal fly ash filter plant Authors Mr. James Keat - United States - Paterson & Cooke Mr. Jason Hamelehle - United States - Paterson & Cooke Mr. Casey Schmitt - United States - Paterson & Cooke Abstract Coal-fired power plants have come under stricter environmental regulations for their waste disposal with some requiring the stored fly ash slurry to not have any bleed water as measured by the paint filter test. Slurry at a solids concentration that passes this test is considered a paste by most definitions. Transporting this paste presents significant technical problems. Instead, some …

Low Carbon Concrete-​ Fair And Rapid Assessment Of Slowly Reacting Cement Concrete, Rod Jones

World of Coal Ash Proceedings

Fairly Assessing Slowing Reacting Cement for Low Carbon Concrete Authors Prof. Rod Jones - United Kingdom - University of Dundee Abstract Responding and reducing the climate emergency concrete construction must play a significant role worldwide. The main of most carbon-limiting technologies is to reduce the Portland clinker content to increasingly high levels, typically with secondary cementitious materials such as fly ash. While it may be possible to design such mixes for a particular strength there are implications for durability. Durability tests are carried out at the standard age of 28 days, however, fly ash is a slowly reacting cement and …

Pathways To Maximise Stored Coal Combustion Products (Ccps)- Partnership Between Nsw Government And Ash Development Association Of Australia​, Craig Heidrich, Warren South

World of Coal Ash Proceedings

Pathways to maximise stored Coal Combustion Products (CCPS): Partnership between NSW Government and Ash Development Association of Australia Authors Mr. Craig Heidrich - Australia - Ash Development Association of Australia Dr. Warren South - Australia - Valkoviki Pty Ltd Abstract ABSRACT: With a background of accelerating change in the electricity market within New South Wales, forecast closures of all coal fired power stations is planned to occur by 2045 -- the issue of supply and management of coal combustion products, being a by-product of the combustion of coal within a coal fired powers station, has been identified as an emerging …

Attenuation Of Metals And Inorganics- Insights From Laboratory Testing Approaches, Larissa Smith, Michael Healey, Jeff Roberts, Allison Kreinberg

World of Coal Ash Proceedings

Natural Attenuation of Metals and Inorganics: Insights from Laboratory Testing Approaches Authors Ms. Larissa Smith - Canada - SiREM Mr. Michael Healey - Canada - SiREM Mr. Jeff Roberts - Canada - SiREM Ms. Allison Kreinberg - United States - Geosyntec Consultants, Inc. Ms. Crystal Wilson - United States - Geosyntec Consultants, Inc. Mr. Lane Dorman - United States - Geosyntec Consultants, Inc. Mr. Andrzej Przepiora - Canada - Geosyntec Consultants, Inc. Abstract Laboratory treatability studies can be used to evaluate and optimize groundwater treatment options for contaminants found at coal combustion residual (CCR) sites. An important consideration in groundwater …

Paper_Attenuation Of Metals And Inorganics: Insights From Laboratory Testing Approaches, Larissa Smith, Michael Healey, Jeff Roberts, Allison Krienberg

World of Coal Ash Proceedings

Laboratory treatability studies can be used to evaluate and optimize groundwater treatment options for contaminants of concern (COCs) found at coal combustion residual (CCR) sites. An important consideration in groundwater treatment selection is the suitability of monitored natural attenuation (MNA) as a treatment component or as a stand-alone passive treatment. This presentation will focus on the use of treatability testing to evaluate natural and enhanced attenuation treatment options for redox sensitive metals in CCR-impacted groundwater. In one demonstration, a comprehensive laboratory program was performed based upon the USEPA’s tiered approach to identify the natural attenuation processes, rates, attenuation capacities, and …

Dissecting Bayes: Using Influence Measures To Test Normative Use Of Probability Density Information Derived From A Sample, Laurence T. Maloney, Keiji Ota

MODVIS Workshop

Bayesian decision theory (BDT) is used to model human performance in tasks where the decision maker must compensate for uncertainty in order to gain rewards and avoid losses. BDT prescribes how the decision maker can combine available data, prior knowledge, and value to reach a decision maximizing expected winnings. Do human decision makers actually use BDT in making decisions? Researchers typically compare overall human performance (total winnings or overall percent correct) to the predictions of BDT but we cannot conclude that BDT is an adequate model for human performance based on just overall performance. We break BDT down into elementary …

Explaining The Staircase Gelb Illusion, Simultaneous Contrast, And Perceptual Fading Of Stabilized Images With A Neural Model Driven By Fixational Eye Movements, Michael E. Rudd

MODVIS Workshop

A neural model of lightness computation driven by fixational eye movements is described and used to simulate various lightness phenomenon, including the Staircase Gelb illusion and its variants, simultaneous contrast, the Chevreul illusion, and perceptual fading of stabilized images. The model provides a precise account of the lightness matches from several experiments, with an overall error of only 1.5%. In the model, spatial maps of transient ON and OFF cell activations—produced as the eyes traverse the visual scene—are sorted by eye movement direction in visual cortex. At a subsequent processing stage, the activations within these maps are summed across space …

Paper_A Study On The Applicability Of Dry Bottom Ash As A Fine Aggregate For Lightweight Aggregate Concrete, Sangchul Shin, Jinman Kim, Hoonsik Hong

World of Coal Ash Proceedings

While wet bottom ash has been used as a lightweight aggregate for a long time, Research on a dry bottom ash emitted from thermal power plants is insufficient. Dry bottom ash has the potential to be used as an excellent lightweight aggregate in the field of construction materials. This study was performed to verify the applicability of dry bottom ash as a fine aggregate in lightweight aggregate concrete. As a result of the study, it was found that the slump loss was not significant up to 75% of the dry bottom ash replacement rate, and the use of dry bottom …

Ash Basin Excavation Under Strict Orders – A Measured Approach, Mark Taylor, Evan Andrews, Longde Jin, Naveen Ganji

World of Coal Ash Proceedings

Ash Basin Excavation Under Strict Orders – A Measured Approach Authors Mr. Mark Taylor - United States - WSP USA, Inc. Mr. EVAN ANDREWS - United States - Sequoia Services Mr. Longde Jin - United States - WSP USA, Inc. Mr. Naveen Ganji - United States - WSP USA, Inc. Abstract A heavy civil contractor in the Southeast US was hired by a major electric utility to restore two retired ash basins to their original condition using the closure-by-removal approach, a 46-acre basin and an 86-acre basin containing about 2.5 and 5 million tons of CCR, respectively. Both basins had …

Groundwater Corrective Action Implementation Issues, Jeremy Hurshman, Dennis Connair

World of Coal Ash Proceedings

Implementation Issues, Groundwater Corrective Action, Laramie River Station, Basin Electric Power Cooperative Authors Mr. Jeremy Hurshman - United States - AECOM Mr. Dennis Connair - United States - AECOM Abstract Groundwater monitoring of an ash pond and landfill complex at the subject site identified the presence of lithium and molybdenum at statistically significant levels (SSLs) above the site-specific groundwater protection standards (GWPSs). Groundwater impact in the sandstone aquifer was delineated and found to be limited to an area of less than 10 acres. An assessment of corrective measures (ACM) was conducted and a public meeting open to interested and affected …

Separation Process And Mechanism Of Lithium And Gallium By Microwave Enhanced Leaching Of High-Alumina Coal Ash, Shenyong Li, Qian Wang, Shuai Kang, Wei Pang

World of Coal Ash Proceedings

Separation process and mechanism of lithium and gallium by microwave enhanced leaching of high-alumina coal ash Authors Dr. SHENYONG LI - China - Hebei University of Engineering Ms. Qian Wang - China - Hebei University of Engineering Mr. Shuai Kang - China - Hebei University of Engineering Ms. Wei Pang - China - Hebei University of Engineering Mr. Longlong Hao - China - Hebei University of Engineering Prof. Shenjun Qin - China - Hebei University of Engineering Abstract With the increasing demand and supply shortage of rare metals, fly ash may become an ideal alternative source for strategic key metals …

Trimble County Ccr Pond Closures, Steven Turner, John Williams, Jarrett Beach

World of Coal Ash Proceedings

The Closure of the Gypsum Storage Pond (GSP) by Removal and Use as Fill in the Bottom Ash Pond (BAP) at the Louisville Gas and Electric (LG&E) Trimble Generating Station Authors Mr. Steven Turner - United States - Tetra Tech, Inc. Mr. John Williams - United States - Louisville Gas and Electric/Kentucky Utilities Mr. Jarrett Beach - United States - LG&E and KU Abstract The GSP was a 40-acre gypsum depository for two pulverized-coal-fired units with a capacity of 514 and 760 megawatts respectively at LG&E Trimble Generating Station. Approximately 1.5MM cubic yards (CY) of gypsum was deposited in the …

A Study On The Applicability Of Dry Bottom Ash As A Fine Aggregate For Lightweight Aggregate Concrete, Sangchul Shin, Jinman Kim

World of Coal Ash Proceedings

A Study on the Applicability of Dry Bottom Ash as a Fine Aggregate for Lightweight Aggregate Concrete Authors Dr. Sangchul Shin - Korea, Republic of - Eco-friendly Concrete Research Center, Kongju National University Dr. Jinman Kim - Korea, Republic of - Department of Green Smart Architectural Engineering, Kongju National University Dr. Hoonsik Hong - Korea, Republic of - Korea Power plant Byproduct Recycling Association Abstract While wet bottom ash has been used as a lightweight aggregate for a long time, Research on a dry bottom ash emitted from thermal power plants is insufficient. Dry ottom ash has the potential to …

Ccr Closure- Best Practices In Project Management Through The Construction Life Cycle, Glen Toepfer

World of Coal Ash Proceedings

CCR Closure: Best Practices in Project Management that Provide Asset Protection Throughout Each Stage of the Construction Life Cycle by Reducing Liabilities, Ensuring Quality and Expediting Regulatory Acceptance. Authors Mr. Glen Toepfer - United States - CQA Solutions Abstract CCR closure can be performed by clean closure through CCR removal and disposal or by closure in place methods. Regardless of the closure method being used, the construction process will have defined stages. The construction cycle begins at conception and seemingly culminates in the completion of either the fieldwork or the operational stage. However, the owner’s liability remains for up to …

Dewatering System Installation Methods For Ash Dewatering And Deep Depressurization, Christopher Gee, Paul Schmall, Shawn Coughlin, Christopher Jones

World of Coal Ash Proceedings

Dewatering System Installation Methods for Ash Dewatering and Deep Depressurization- A Case Study Authors Mr. Christopher Gee - United States - Dominion Dr. Paul Schmall - United States - Keller Mr. Shawn Coughlin - United States - Keller Mr. Christopher Jones - United States - Haley & Aldrich Inc. Abstract Hydrogeologic conditions of this project require a multi-faceted approach to facilitate not only CCR dewatering but also deep depressurization of underlying highly permeable soils. Previous construction experienced significant and sustained groundwater inflows from beneath the ponded ash because the pond was built over the pre-existing river bed in braided stream …

Evaluating Monitored Natural Attenuation​ Paired With Source Control​, Kelly Ferri, Craig Eady, Kathy Webb

World of Coal Ash Proceedings

Effective Remedial Measure: Evaluating Monitored Natural Attenuation Paired with Source Control Authors Mrs. Kelly Ferri - United States - SynTerra Corporation Mr. Craig Eady - United States - SynTerra Corporation Mrs. Kathy Webb - United States - SynTerra Corporation Abstract Monitored natural attenuation (MNA) coupled with source control is a viable component of remedial technologies evaluated under an assessment of corrective measures for coal combustion product (CCP) units with Appendix IV constituent concentrations greater than groundwater protection standards (GWPSs) downgradient of the waste boundary. To demonstrate the effectiveness of source control and MNA, groundwater data and geochemical conditions from four …

Lessons Learned From Landfill Construction Inside Former Ash Basins, John Bove

World of Coal Ash Proceedings

Lessons Learned from Landfill Construction Inside Former Ash Ponds Authors Mr. John Bove - United States - AECOM Abstract Lessons Learned from Landfill Construction Inside Former Ash Ponds John Bove1 1AECOM, 6000 Fairview Road, Suite 200, Charlotte NC 28210 KEYWORDS: Landfill, Ash Pond ABSTRACT Former ash pond sites can be good candidates for siting engineered landfills to place excavated ash from closure by removal sites and future production ash from power plants. For closure in place ash will need to be excavated within an area before building a landfill. These sites offer cost advantages over greenfield landfills such as hauling …

The Art World Of Isabella Gardner And Fenway Court, Ivy Kolkana

Symposium of Student Scholars

"The Art World of Isabella Gardner and Fenway Court" presents a comprehensive examination of the influential cultural milieu created by Isabella Stewart Gardner, focusing on the inception and evolution of Fenway Court, now the Isabella Stewart Gardner Museum. This paper delved into the intricate tapestry of Gardner's relationships with prominent artists such as John Singer Sargent, Anders Leonard Zorn, James Abbott McNeill Whistler, Denis Bunker, and several other female artists, illuminating her pivotal role as a patron and tastemaker in the late 19th and early 20th century America.

Beginning with the genesis of the museum, the paper traces Gardner's vision …

Depression Among College Students: Differences By Race, Generation Status, And Their Intersection, Kenzie Thomas

Symposium of Student Scholars

Previous research has shown that depression can negatively impact college students. Yet, there is a major gap in the literature regarding differences in depression among college students by race, generation status, and their intersection. One study demonstrated that first-generation college students (FGCS; neither parent obtained a college degree) experience higher levels of depressive symptoms compared to continuing-generation college students (CGCS; at least one parent obtained a college degree). Similarly, another study found that African American college students endure more experiences of hopelessness and depression than their counterparts. Still, this evidence is scant, and there remains little research on depression as …

Daylighting In Buildings: Investigating The Relationship Between Daylight Levels And Building Compactness In Various Contemporary Architectural Types. [Efficient Typology Classification], Andrew Welch, Ermal Shpuza Phd

Symposium of Student Scholars

One of the key ways of improving the energy efficiency of a building is to enhance the daylight levels and reduce the need for artificial lighting. Good daylight levels are also associated with increased productivity and the well-being of a building's occupants. Daylight levels are often a direct function of the floorplate depth, where locations near the windows receive more daylight, and those deep inside the buildings receive less. As a result, shallow floorplates and elongated buildings are usually related to higher daylight levels. However, shallow buildings that have more natural light are also associated with greater construction costs due …

Advancements In South Korea's Multilingual And Multicultural Initiatives: Perspectives From Bilingual Immigrant Coaches And Korean Government Officials Working In Health Family Support Centers, Seongyo Gwon, Jayoung Choi

Symposium of Student Scholars

Health Family Support Centers in South Korea play a pivotal role in promoting multilingualism and multiculturalism in South Korea that practices Korean-only assimilation policies. With an increased influx of multicultural immigrants, these centers provide assistance and services to immigrants. These centers also serve as a hub for both immigrants who have gained proficiency in the Korean language and culture also work there as bilingual coaches and translators, and dedicated Koreans fostering cultural harmony. Thus, it is crucial to examine experiences and perspectives of employees striving for immigrant equity in South Korea at these centers.

This study explores the perspectives and …

Pregnancy Behind Bars: Exploring The Impact Of Incarceration On Prenatal And Postnatal Care For Female Inmates, Caitlin Callahan, Anisah Bagasra, Meghan Bankhead

Symposium of Student Scholars

Incarcerated women have a constitutionally protected right to obtain appropriate medical care. Past research has found that “38 states had inadequate or no prenatal care in their prisons” (NWsLC, 2010). A report from The US Department of Justice states that “46% of pregnant imprisoned women reported they received no pregnancy care” (Maruschak, 2008). There is a gap in the literature of analyzing primary accounts of pregnant inmates. The current study is investigating the interaction of incarceration and the available care and quality of care given to female inmates in American correctional institutions. This study is comprised of a qualitative video …

Design And Modeling To Dewater​ A Partially Composite-Covered Ash Pond, Michael Thornbrue

World of Coal Ash Proceedings

DESIGN AND MODELING TO DEWATER A PARTIALLY CLOSED ASH POND Authors Mr. Michael Thornbrue - United States - Atlas Technical Consultants Abstract An Electrical Power Supplier in the Midwest retained Atlas Technical Consultants (Atlas) to design a system to dewater a partially closed ash pond and predict its performance over a period of five (5) years. Prior to January 2022, the client began closure of the ash pond and completed installation of a composite cover over about 40% of the pond’s area. Atlas investigated the pond’s geology and concluded that the bottom and perimeter embankments consist of lean clay (k≈5x10‑8 …

Epa’S Value Engineering Approach For Gypsum Stack Closure, Michael Ayers, Craig Zeller

World of Coal Ash Proceedings

EPA’s Value Engineering Approach for Gypsum Stack Closure Authors Mr. Michael Ayers - United States - Watershed Geo Mr. Craig Zeller - United States - US EPA Abstract In February 2017, US EPA Region 4 assumed responsibility for water treatment and daily operations for an unlined and open 350-acre gypsum stack located in Pascagoula, Mississippi. The gypsum stack contains approximately 15M cubic yards of phosphogypsum with elevated levels of nutrients and acidic pH. To the immediate east of the facility is one of the most biologically productive estuarine ecosystems in the Gulf of Mexico region. An uncontrolled and untreated release …

Build To Last- Innovations For Water And Waste Water Conveyance Using Geosynthetic Cementitious Composite Mats (Gccms) Henry Miller Irrigation District - A Case History, Nathan Ivy

World of Coal Ash Proceedings

Emerging technologies for water conveyance and containment Authors Mr. Nathan Ivy - United States - Concrete Canvas Abstract GCCM’s represent the newest class of geosynthetics that can be used for water conveyance and containment applications. Since their initial introduction nearly 15 years ago, ASTM D8364-Standard Specification for Geosynthetic Cementitious Composite Mats (GCCM) Materials has been developed as the internationally recognized standard for testing and classifying GCCM as Type I, II or III. All products discussed herein meet or exceed all aspects of this standard – regardless of type. These products combine both a concrete – hard armor – top surface …

Updating Your Asset Retirement Obligations, Ron Hager

World of Coal Ash Proceedings

ASSET RETIREMENT OBLIGATIONS: UPDATING YOUR AROS BASED ON THE PROPOSED LEGACY CCR SURFACE RULE Authors Mr. Ron Hager - United States - Burns & McDonnell Abstract On May 18, 2023, EPA proposed regulatory requirements for inactive surface impoundments at inactive facilities. This proposal responds to the 2018 U.S. Court of Appeals for the District of Columbia Circuit ruling that vacated the exemption for legacy CCR surface impoundments from the CCR regulations. The USEPA contends that Legacy CCR surface impoundments are more likely to be unlined and unmonitored, making them more prone to leaks and structural problems than units at facilities …

Accounting For The Structure Of Noise In Binocular Rivalry With A Bayesian Sampling Approach, Stella Qian, Jake Spicer, Adam N. Sanborn

MODVIS Workshop

Binocular rivalry occurs when two eyes are presented with incompatible images; observers experience temporal alternations of the two eyes’ images. Such descriptions often mislead readers to assume regular rhythmic rivalry dynamics.

However, rivalry dynamics are noisy: percept durations show high variability. (1) The percept durations follow a gamma distribution. (2) Autocorrelations in the percept durations, although widely known, receive little attention in modelling. (3) Similarly, there is a substantial chance of and individual differences on returning to the same exclusive percept after a mixture percept (van Ee, 2009). These observations are unlikely to be explained by injecting Gaussian noise in …