Emily Sarver - Academia.edu (original) (raw)
Papers by Emily Sarver
Project Title: Proof-of-concept work to demonstrate optical microscopy with image analysis as a t... more Project Title: Proof-of-concept work to demonstrate optical microscopy with image analysis as a tool for semi-continuous coal mine dust monitoring Grant Number: AFC316FO-74 Organization: Virginia Tech Principal Investigator: Emily Sarver Co-principal Investigators: Cigdem Keles (Virginia Tech) John R. Saylor (Clemson University) Research Associate: Nestor Santa (Virginia Tech) Contact Information: esarver@vt.edu, 540-231-8139 Period of Performance: Oct 1, 2019 – Jan 31, 2021
Silica Exposure Appears Causal in Resurgent Severe Coal Workers’ Pneumoconiosis
Safety and Health at Work
Minerals
Application of fine, inert ‘rock dust’ (RD) to the surfaces in underground coal mines is a common... more Application of fine, inert ‘rock dust’ (RD) to the surfaces in underground coal mines is a common method for mitigating coal dust explosion hazards. However, due to its size, RD has the potential to contribute to the respirable coal mine dust (RCMD) concentration. Though the RD component of RCMD does not appear to pose the sort of health hazards associated with other components such as crystalline silica, understanding its relative abundance may be quite helpful for evaluating and controlling primary dust sources. Given that RD products are frequently comprised of high-purity limestone (i.e., primarily calcite mineral), calcite may serve as a suitable proxy for measuring RD. To estimate the mass percentage of calcite in RCMD samples, this study demonstrates the successful application of direct-on-filter (DOF) Fourier-transform infrared (FTIR) spectroscopy. Incidentally, DOF FTIR has been the focus of recent efforts to enable rapid measurement of crystalline silica in RCMD. Concurren...
Insights Into Non-Uniform Copper and Brass Corrosion in Potable Water Systems
Non-uniform corrosion of copper and brass in potable water systems poses both economic and enviro... more Non-uniform corrosion of copper and brass in potable water systems poses both economic and environmental problems associated with premature plumbing failures and release of metals. With respect to copper pitting corrosion, it was found that forensic testing (i.e., in pipe-loops) is the only investigative technique that can closely mimic conditions found in real water systems and produce unambiguous results; and, if used in combination with electrochemical techniques, it may also provide some mechanistic insights into the pitting process. Using pipe-loops, it was demonstrated that copper pitting in aggressive water qualities (i.e., chlorinated, high pH and low alkalinity) is deterministic and reproducible. Additionally, the effects of various chemical and physical factors on pitting were investigated. Overall, increased flow velocity and frequency, increased chlorine residual and decreased hardness were found to accelerate pitting; whereas increased phosphate and silica were found to...
Copper Pitting and Brass Dezincification : Chemical and Physical Effects [ Project # 4289 ]
OBJECTIVES: The key hypothesis of this project was that both chemical and physical factors associ... more OBJECTIVES: The key hypothesis of this project was that both chemical and physical factors associated with real plumbing systems may influence copper pitting and brass dezincification corrosion, and thus the project was aimed at better understanding these factors. In addition to a comprehensive review of the literature on brass dezincification in potable water systems, experimental work was undertaken to meet the following objectives:
Respirable dust in coal mining environments has long been a concern for occupational health. Over... more Respirable dust in coal mining environments has long been a concern for occupational health. Over the past several decades, much effort has been devoted to reducing dust exposures in these environments, and rates of coal workers’ pneumoconiosis (CWP) have dropped significantly. However, in some regions, including parts of Central Appalachia it appears that incidence of CWP has recently been on the rise. This trend is yet unexplained, but a possible factor might be changes in specific dust characteristics, such as particle composition, size or shape. Prior work in our research group has developed a standardized methodology for analyzing coal mine dust particles on polycarbonate filter media using scanning electron microscopy with energy dispersive x-ray (SEMEDX). While the method allows individual particles to be characterized, it is very time-intensive because the instrument user must interrogate each particle manually; this limits the number of particles that can practically be cha...
Satellite remote sensing-based estimates of biomass production on reclaimed coal mines
Mining Engineering, 2014
Minerals
The re-identification of coal workers’ pneumoconiosis in Queensland in 2015 has prompted improvem... more The re-identification of coal workers’ pneumoconiosis in Queensland in 2015 has prompted improvements in exposure monitoring and health surveillance in Australia. The potential consequences of excessive exposure to respirable dust may depend upon the size, shape and mineralogical classes of the dust. Technology has now advanced to the point that the dust characteristics can be explored in detail. This research collected respirable dust samples from four operating underground coal mines in Australia for characterization analysis using scanning electron microscopy (SEM) with energy dispersive X-ray (EDX). The research found multiple mineralogical classes present with their own particle size distributions. The variation between mines appears to have had a larger effect on particle size distribution than the differences in mining processes within individual mines. This may be due to variations in the geologic conditions, seam variation or mining conditions.
2018 ASEE Annual Conference & Exposition Proceedings
As an anthropologist, her research interests focus around the mining and energy industries, with ... more As an anthropologist, her research interests focus around the mining and energy industries, with particular emphasis in corporate social responsibility, engineers, labor and gender. She is the author of Mining Coal and Undermining Gender: Rhythms of Work and Family in the American West, which was funded by the National Endowment for the Humanities and the National Science Foundation. She is currently investigating the intersections between engineering and CSR on the NSF grant "The Ethics of Extraction: Integrating Corporate Social Responsibility into Engineering Education." Dr. Nicole M. Smith, Colorado School of Mines Dr. Smith is a Assistant Professor in Mining Engineering at the Colorado School of Mines. She is a cultural anthropologist with research and teaching interests in livelihoods and extractive industries, corporate social responsibility, indigenous peoples, artisanal and small-scale mining, and engineering education. Dr. Greg Rulifson P.E., Colorado School of Mines Greg currently teaches in Humanitarian Engineering at Mines. Greg earned his bachelor's degree in Civil Engineering with a minor in Global Poverty and Practice from UC Berkeley where he acquired a passion for using engineering to facilitate developing communities' capacity for success. He earned his master's degree in Structural Engineering and Risk Analysis from Stanford University. His PhD work at CU Boulder focused on how student's connections of social responsibility and engineering change throughout college as well as how engineering service is valued in employment and supported in the workplace.
2019 ASEE Annual Conference & Exposition Proceedings
She is an anthropologist with two major research areas: 1) the sociocultural dynamics of extracti... more She is an anthropologist with two major research areas: 1) the sociocultural dynamics of extractive and energy industries, with a focus on corporate social responsibility, social justice, labor, and gender and 2) engineering education, with a focus on socioeconomic class and social responsibility.
2020 ASEE Virtual Annual Conference Content Access Proceedings
and Research. She is an anthropologist with two major research areas: 1) the sociocultural dynami... more and Research. She is an anthropologist with two major research areas: 1) the sociocultural dynamics of extractive and energy industries, with a focus on corporate social responsibility, social justice, labor, and gender and 2) engineering education, with a focus on socioeconomic class and social responsibility. She is currently completing a book manuscript on the intersection of engineering and corporate social responsibility.
Water
Issues surrounding water infrastructure, access, and quality are well documented in the Central A... more Issues surrounding water infrastructure, access, and quality are well documented in the Central Appalachian region of the United States. Even in cases where residents have in-home piped point-of-use (POU) water, some rely on alternative drinking water sources for daily needs—including water collection from roadside springs. This effort aims to better understand and document spring usage in this region by identifying the factors that influence drinking water source selection and comparing household and spring water quality to Safe Drinking Water Act (SDWA) health-based and aesthetic contaminant recommendations. Households were recruited from communities surrounding known springs in three states (Kentucky, Virginia, and West Virginia). First- and second-draw, in-home POU tap water samples were collected from participating households and compared to samples collected from local springs on the same day. Samples were analyzed for fecal indicator bacteria and inorganic ions. Study partici...
Beyond conventional metrics: Comprehensive characterization of respirable coal mine dust
International Journal of Coal Geology
Abstract Conventional practice in monitoring and control of respirable coal mine dust has focused... more Abstract Conventional practice in monitoring and control of respirable coal mine dust has focused on the total mass concentration and the crystalline silica mass fraction of personal exposures. For decades under this approach, as dust exposures in US mines declined, so did the incidence of occupational lung diseases. In the late 1990s, however, disease rates began to rise significantly with little or no apparent increase in the conventional dust metrics. Based on the geographic clustering of disease reports in parts of central Appalachia, several contributing factors have been suggested, including possible changes in dust characteristics as thin-seam mining has become increasingly common. However, data on anything beyond conventional dust metrics is almost non-existent. The current study represents an ongoing effort by the authors to comprehensively characterize respirable coal mine dust. Here, samples from eight mines in central and northern Appalachia were analyzed to determine: particle size and mineralogy distributions across a wide size range (~100–10,000 nm); potentially bioaccessible and total acid-soluble mass concentrations of metals and trace elements; and mass concentrations of polyaromatic hydrocarbons including 1-nitropyrene, which may be indicators of diesel exhaust. Results showed that dust characteristics can vary widely between and within mines. But several general observations were noted, such as a predominance of sub-micron particles, including those associated with both diesel exhaust and dust generated from cutting geologic strata in the mine or application of rock dusting products. Additionally, there appeared to be an inordinate amount of dust generated from cutting rock strata, as compared to coal strata. A correlation analysis was also conducted on a total of 40 dust characteristic variables, which may provide further insights to the source(s) of some constituents.
Copper pitting in chlorinated, high-pH potable water
Journal - American Water Works Association
Copper pitting in plumbing systems can have expensive and hazardous consequences, yet little is k... more Copper pitting in plumbing systems can have expensive and hazardous consequences, yet little is known about the nature of the problem (ie, conditions that cause or contribute to pitting) or the most effective means of studying it. In this comprehensive look at copper ...
Interactive effects of water quality, physical habitat, and watershed anthropogenic activities on stream ecosystem health
Water research, Mar 1, 2018
Ecological degradation of streams remains a major environmental concern worldwide. While stream r... more Ecological degradation of streams remains a major environmental concern worldwide. While stream restoration has received considerable attention, mitigation efforts focused on the improvement of physical habitat have not proven completely effective. Several small-scale studies have emphasized that effective restoration strategies require a more holistic understanding of the variables at play, although the generalization of the findings based on the small-scale studies remains unclear. Using a comprehensive statewide stream monitoring database from West Virginia (WV), a detailed landscape dataset, and a machine learning algorithm, this study explores the interactive impacts of water quality and physical habitat on stream ecosystem health as indicated by benthic macroinvertebrate scores. Given the long history of energy extraction in this region (i.e., coal mining and oil/gas production), investigation of energy extraction influences is highlighted. Our results demonstrate that a combi...
Ecological Engineering
Ecological mitigation in Central Appalachia often takes one of two approaches: a water qualitydri... more Ecological mitigation in Central Appalachia often takes one of two approaches: a water qualitydriven focus (TMDLs), or a geomorphological focus on stream/habitat restoration (404 permit-related requirements). While often successful at reducing in-stream pollutants or restoring stable hydrology respectively, recent studies have shown that neither approach appreciably improves aquatic ecosystem health. We report here on a field sampling campaign along the Kentucky-Virginia border aimed at identifying primary macroinvertebrate stressors in order to inform ecological remediation efforts and how those efforts might fit into the current regulatory structure. Over two years, we collected 178 observations of benthic species diversity at 36 unique sites representing watersheds of varying surface disturbance and anthropogenic activities, along with associated data from rapid bioassessment protocols (RBPs). Using land use metrics (derived from GIS data), water quality data, habitat metrics, and stream condition indices, principal component analysis (PCA) identified surface disturbance, forest cover, and specific conductivity as significant variables comprising the first PC. Habitat appears to be a secondary driver affecting community sensitivity with channel alteration, bank vegetation, riparian vegetation, and epifaunal substrate contributing significantly to the second PC. PERMANOVA analysis showed these groups to be significantly different from one another (p = 0.001), R 2 = 0.44. Change point analysis via 500 bootstrapped replications identified shifts in community composition means at 326, 609, and 1065 mS/cm along the conductivity gradient, and habitat change points at 42.6 and 58.2 along the composite habitat gradient. These findings suggest that approaches that improve water quality, upland hydrology, and localized habitat structures may simultaneously be necessary to improve aquatic ecosystem health.
Respirable coal mine dust characteristics in samples collected in central and northern Appalachia
International Journal of Coal Geology
Abstract Increased incidence of lung diseases among underground coal miners in parts of Appalachi... more Abstract Increased incidence of lung diseases among underground coal miners in parts of Appalachia in the US has prompted new research respirable dust characteristics. Between 2014 and 2015, 210 samples of respirable dust were collected in various locations of eight underground coal mines in three distinct Appalachian regions. The mines vary in terms of mining method, coal seam thickness, and mined strata geology. A computer-controlled SEM-EDX routine was used to analyze the dust to determine distributions of particle size, aspect ratio, and mineralogy classification. Statistical analysis of results showed that significant differences in dust characteristics exist between and within mine regions, and by sampling location. Most notably, samples from mid- and south-central Appalachia had relatively higher percentages of alumino-silicates and quartz, consistent with cutting more rock along with the coal in these mines; whereas, samples from northern Appalachia had higher percentages of carbonate, which is largely attributed to heavy rock dusting in the sampled mines. Compared to other regions, samples from mid-central Appalachia also had higher percentages of very small particles and samples from south-central Appalachia had higher percentages of elongated particles. Overall, samples collected near production activities or in return airways had higher percentages of small particles than in other sampling locations. Based on samples collected right at the mine face, results additionally suggest that cutting rock strata may produce an inordinate amount of respirable dust as compared to cutting coal.
Minerals
A recent resurgence in coal workers' pneumoconiosis (or "black lung") and concerns over other rel... more A recent resurgence in coal workers' pneumoconiosis (or "black lung") and concerns over other related respiratory illnesses have highlighted the need to elucidate characteristics of airborne particulates in occupational environments. A better understanding of particle size, aspect ratio, or chemical composition may offer new insights regarding causal factors of such illnesses. Scanning electron microscopy analysis using energy dispersive X-ray (SEM-EDX) can be used to estimate these particle characteristics. If conducted manually, such work can be very time intensive, limiting the number of particles that can be analyzed. Moreover, potential exists for user bias in interpretation of EDX spectra. A computer-controlled (CC) routine, on the other hand, can allow similar analysis at a much faster rate, increasing total particle counts and reproducibility of results. This paper describes a CCSEM-EDX routine specifically developed for analysis of respirable dust samples from coal mines. The routine is verified based on reliability of results obtained on samples of known materials, and reproducibility of results obtained on a set of 10 dust samples collected in the field. The characteristics of the field samples are also discussed with respect to mine occupational environments.
Journal of The Electrochemical Society, 2016
Flow electrification" occurs whenever a fluid passes along a charged surface, creating an electro... more Flow electrification" occurs whenever a fluid passes along a charged surface, creating an electrokinetic "streaming current" or "streaming potential' and is known to cause non-uniform corrosion (and other) problems in non-aqueous fluids. After observing unusual corrosion failures of copper in relatively low conductivity (≈150 μS/cm) potable water, a series of laboratory studies was conducted that verified flow electrification could also develop in aqueous systems and contribute to non-uniform corrosion. Relatively high direct streaming currents along pipelines were quantified in model systems with plastic dielectrics, which accelerated corrosion on the affected pipe section by up to 0.5 μA/cm 2 (assuming uniform corrosion). Very rapid non-uniform pipe failures (i.e., full wall penetration in 7 months) occurred in a system without dielectrics simulating a potable water recirculation system. The effects of flow electrification were virtually eliminated by addition of low levels of zinc phosphate, an inhibitor used in approximate 25% of potable water distribution systems. Flow electrification was also observed in plastic pipe systems with brass connectors.
Resources, 2015
A key consideration for responsible development of mineral and energy resources is the well-being... more A key consideration for responsible development of mineral and energy resources is the well-being of workers. Respirable dust in mining environments represents a serious concern for occupational health. In particular, coal miners can be exposed to a variety of dust characteristics depending on their work activities, and some exposures may pose risk for lung diseases like CWP and silicosis. As underscored by common regulatory frameworks, respirable dust exposures are generally characterized on the basis of total mass concentration, and also the silica mass fraction. However, relatively little emphasis has been placed on other dust characteristics that may be important in terms of identifying health risks. Comprehensive particle-level analysis to estimate chemistry, size, and shape distributions of particles is possible. This paper describes a standard methodology for characterization of respirable coal mine dust using scanning electron microscopy (SEM) with energy dispersive X-ray (EDX). Preliminary verification of the method is shown based several dust samples collected from an underground mine in Central Appalachia.
Project Title: Proof-of-concept work to demonstrate optical microscopy with image analysis as a t... more Project Title: Proof-of-concept work to demonstrate optical microscopy with image analysis as a tool for semi-continuous coal mine dust monitoring Grant Number: AFC316FO-74 Organization: Virginia Tech Principal Investigator: Emily Sarver Co-principal Investigators: Cigdem Keles (Virginia Tech) John R. Saylor (Clemson University) Research Associate: Nestor Santa (Virginia Tech) Contact Information: esarver@vt.edu, 540-231-8139 Period of Performance: Oct 1, 2019 – Jan 31, 2021
Silica Exposure Appears Causal in Resurgent Severe Coal Workers’ Pneumoconiosis
Safety and Health at Work
Minerals
Application of fine, inert ‘rock dust’ (RD) to the surfaces in underground coal mines is a common... more Application of fine, inert ‘rock dust’ (RD) to the surfaces in underground coal mines is a common method for mitigating coal dust explosion hazards. However, due to its size, RD has the potential to contribute to the respirable coal mine dust (RCMD) concentration. Though the RD component of RCMD does not appear to pose the sort of health hazards associated with other components such as crystalline silica, understanding its relative abundance may be quite helpful for evaluating and controlling primary dust sources. Given that RD products are frequently comprised of high-purity limestone (i.e., primarily calcite mineral), calcite may serve as a suitable proxy for measuring RD. To estimate the mass percentage of calcite in RCMD samples, this study demonstrates the successful application of direct-on-filter (DOF) Fourier-transform infrared (FTIR) spectroscopy. Incidentally, DOF FTIR has been the focus of recent efforts to enable rapid measurement of crystalline silica in RCMD. Concurren...
Insights Into Non-Uniform Copper and Brass Corrosion in Potable Water Systems
Non-uniform corrosion of copper and brass in potable water systems poses both economic and enviro... more Non-uniform corrosion of copper and brass in potable water systems poses both economic and environmental problems associated with premature plumbing failures and release of metals. With respect to copper pitting corrosion, it was found that forensic testing (i.e., in pipe-loops) is the only investigative technique that can closely mimic conditions found in real water systems and produce unambiguous results; and, if used in combination with electrochemical techniques, it may also provide some mechanistic insights into the pitting process. Using pipe-loops, it was demonstrated that copper pitting in aggressive water qualities (i.e., chlorinated, high pH and low alkalinity) is deterministic and reproducible. Additionally, the effects of various chemical and physical factors on pitting were investigated. Overall, increased flow velocity and frequency, increased chlorine residual and decreased hardness were found to accelerate pitting; whereas increased phosphate and silica were found to...
Copper Pitting and Brass Dezincification : Chemical and Physical Effects [ Project # 4289 ]
OBJECTIVES: The key hypothesis of this project was that both chemical and physical factors associ... more OBJECTIVES: The key hypothesis of this project was that both chemical and physical factors associated with real plumbing systems may influence copper pitting and brass dezincification corrosion, and thus the project was aimed at better understanding these factors. In addition to a comprehensive review of the literature on brass dezincification in potable water systems, experimental work was undertaken to meet the following objectives:
Respirable dust in coal mining environments has long been a concern for occupational health. Over... more Respirable dust in coal mining environments has long been a concern for occupational health. Over the past several decades, much effort has been devoted to reducing dust exposures in these environments, and rates of coal workers’ pneumoconiosis (CWP) have dropped significantly. However, in some regions, including parts of Central Appalachia it appears that incidence of CWP has recently been on the rise. This trend is yet unexplained, but a possible factor might be changes in specific dust characteristics, such as particle composition, size or shape. Prior work in our research group has developed a standardized methodology for analyzing coal mine dust particles on polycarbonate filter media using scanning electron microscopy with energy dispersive x-ray (SEMEDX). While the method allows individual particles to be characterized, it is very time-intensive because the instrument user must interrogate each particle manually; this limits the number of particles that can practically be cha...
Satellite remote sensing-based estimates of biomass production on reclaimed coal mines
Mining Engineering, 2014
Minerals
The re-identification of coal workers’ pneumoconiosis in Queensland in 2015 has prompted improvem... more The re-identification of coal workers’ pneumoconiosis in Queensland in 2015 has prompted improvements in exposure monitoring and health surveillance in Australia. The potential consequences of excessive exposure to respirable dust may depend upon the size, shape and mineralogical classes of the dust. Technology has now advanced to the point that the dust characteristics can be explored in detail. This research collected respirable dust samples from four operating underground coal mines in Australia for characterization analysis using scanning electron microscopy (SEM) with energy dispersive X-ray (EDX). The research found multiple mineralogical classes present with their own particle size distributions. The variation between mines appears to have had a larger effect on particle size distribution than the differences in mining processes within individual mines. This may be due to variations in the geologic conditions, seam variation or mining conditions.
2018 ASEE Annual Conference & Exposition Proceedings
As an anthropologist, her research interests focus around the mining and energy industries, with ... more As an anthropologist, her research interests focus around the mining and energy industries, with particular emphasis in corporate social responsibility, engineers, labor and gender. She is the author of Mining Coal and Undermining Gender: Rhythms of Work and Family in the American West, which was funded by the National Endowment for the Humanities and the National Science Foundation. She is currently investigating the intersections between engineering and CSR on the NSF grant "The Ethics of Extraction: Integrating Corporate Social Responsibility into Engineering Education." Dr. Nicole M. Smith, Colorado School of Mines Dr. Smith is a Assistant Professor in Mining Engineering at the Colorado School of Mines. She is a cultural anthropologist with research and teaching interests in livelihoods and extractive industries, corporate social responsibility, indigenous peoples, artisanal and small-scale mining, and engineering education. Dr. Greg Rulifson P.E., Colorado School of Mines Greg currently teaches in Humanitarian Engineering at Mines. Greg earned his bachelor's degree in Civil Engineering with a minor in Global Poverty and Practice from UC Berkeley where he acquired a passion for using engineering to facilitate developing communities' capacity for success. He earned his master's degree in Structural Engineering and Risk Analysis from Stanford University. His PhD work at CU Boulder focused on how student's connections of social responsibility and engineering change throughout college as well as how engineering service is valued in employment and supported in the workplace.
2019 ASEE Annual Conference & Exposition Proceedings
She is an anthropologist with two major research areas: 1) the sociocultural dynamics of extracti... more She is an anthropologist with two major research areas: 1) the sociocultural dynamics of extractive and energy industries, with a focus on corporate social responsibility, social justice, labor, and gender and 2) engineering education, with a focus on socioeconomic class and social responsibility.
2020 ASEE Virtual Annual Conference Content Access Proceedings
and Research. She is an anthropologist with two major research areas: 1) the sociocultural dynami... more and Research. She is an anthropologist with two major research areas: 1) the sociocultural dynamics of extractive and energy industries, with a focus on corporate social responsibility, social justice, labor, and gender and 2) engineering education, with a focus on socioeconomic class and social responsibility. She is currently completing a book manuscript on the intersection of engineering and corporate social responsibility.
Water
Issues surrounding water infrastructure, access, and quality are well documented in the Central A... more Issues surrounding water infrastructure, access, and quality are well documented in the Central Appalachian region of the United States. Even in cases where residents have in-home piped point-of-use (POU) water, some rely on alternative drinking water sources for daily needs—including water collection from roadside springs. This effort aims to better understand and document spring usage in this region by identifying the factors that influence drinking water source selection and comparing household and spring water quality to Safe Drinking Water Act (SDWA) health-based and aesthetic contaminant recommendations. Households were recruited from communities surrounding known springs in three states (Kentucky, Virginia, and West Virginia). First- and second-draw, in-home POU tap water samples were collected from participating households and compared to samples collected from local springs on the same day. Samples were analyzed for fecal indicator bacteria and inorganic ions. Study partici...
Beyond conventional metrics: Comprehensive characterization of respirable coal mine dust
International Journal of Coal Geology
Abstract Conventional practice in monitoring and control of respirable coal mine dust has focused... more Abstract Conventional practice in monitoring and control of respirable coal mine dust has focused on the total mass concentration and the crystalline silica mass fraction of personal exposures. For decades under this approach, as dust exposures in US mines declined, so did the incidence of occupational lung diseases. In the late 1990s, however, disease rates began to rise significantly with little or no apparent increase in the conventional dust metrics. Based on the geographic clustering of disease reports in parts of central Appalachia, several contributing factors have been suggested, including possible changes in dust characteristics as thin-seam mining has become increasingly common. However, data on anything beyond conventional dust metrics is almost non-existent. The current study represents an ongoing effort by the authors to comprehensively characterize respirable coal mine dust. Here, samples from eight mines in central and northern Appalachia were analyzed to determine: particle size and mineralogy distributions across a wide size range (~100–10,000 nm); potentially bioaccessible and total acid-soluble mass concentrations of metals and trace elements; and mass concentrations of polyaromatic hydrocarbons including 1-nitropyrene, which may be indicators of diesel exhaust. Results showed that dust characteristics can vary widely between and within mines. But several general observations were noted, such as a predominance of sub-micron particles, including those associated with both diesel exhaust and dust generated from cutting geologic strata in the mine or application of rock dusting products. Additionally, there appeared to be an inordinate amount of dust generated from cutting rock strata, as compared to coal strata. A correlation analysis was also conducted on a total of 40 dust characteristic variables, which may provide further insights to the source(s) of some constituents.
Copper pitting in chlorinated, high-pH potable water
Journal - American Water Works Association
Copper pitting in plumbing systems can have expensive and hazardous consequences, yet little is k... more Copper pitting in plumbing systems can have expensive and hazardous consequences, yet little is known about the nature of the problem (ie, conditions that cause or contribute to pitting) or the most effective means of studying it. In this comprehensive look at copper ...
Interactive effects of water quality, physical habitat, and watershed anthropogenic activities on stream ecosystem health
Water research, Mar 1, 2018
Ecological degradation of streams remains a major environmental concern worldwide. While stream r... more Ecological degradation of streams remains a major environmental concern worldwide. While stream restoration has received considerable attention, mitigation efforts focused on the improvement of physical habitat have not proven completely effective. Several small-scale studies have emphasized that effective restoration strategies require a more holistic understanding of the variables at play, although the generalization of the findings based on the small-scale studies remains unclear. Using a comprehensive statewide stream monitoring database from West Virginia (WV), a detailed landscape dataset, and a machine learning algorithm, this study explores the interactive impacts of water quality and physical habitat on stream ecosystem health as indicated by benthic macroinvertebrate scores. Given the long history of energy extraction in this region (i.e., coal mining and oil/gas production), investigation of energy extraction influences is highlighted. Our results demonstrate that a combi...
Ecological Engineering
Ecological mitigation in Central Appalachia often takes one of two approaches: a water qualitydri... more Ecological mitigation in Central Appalachia often takes one of two approaches: a water qualitydriven focus (TMDLs), or a geomorphological focus on stream/habitat restoration (404 permit-related requirements). While often successful at reducing in-stream pollutants or restoring stable hydrology respectively, recent studies have shown that neither approach appreciably improves aquatic ecosystem health. We report here on a field sampling campaign along the Kentucky-Virginia border aimed at identifying primary macroinvertebrate stressors in order to inform ecological remediation efforts and how those efforts might fit into the current regulatory structure. Over two years, we collected 178 observations of benthic species diversity at 36 unique sites representing watersheds of varying surface disturbance and anthropogenic activities, along with associated data from rapid bioassessment protocols (RBPs). Using land use metrics (derived from GIS data), water quality data, habitat metrics, and stream condition indices, principal component analysis (PCA) identified surface disturbance, forest cover, and specific conductivity as significant variables comprising the first PC. Habitat appears to be a secondary driver affecting community sensitivity with channel alteration, bank vegetation, riparian vegetation, and epifaunal substrate contributing significantly to the second PC. PERMANOVA analysis showed these groups to be significantly different from one another (p = 0.001), R 2 = 0.44. Change point analysis via 500 bootstrapped replications identified shifts in community composition means at 326, 609, and 1065 mS/cm along the conductivity gradient, and habitat change points at 42.6 and 58.2 along the composite habitat gradient. These findings suggest that approaches that improve water quality, upland hydrology, and localized habitat structures may simultaneously be necessary to improve aquatic ecosystem health.
Respirable coal mine dust characteristics in samples collected in central and northern Appalachia
International Journal of Coal Geology
Abstract Increased incidence of lung diseases among underground coal miners in parts of Appalachi... more Abstract Increased incidence of lung diseases among underground coal miners in parts of Appalachia in the US has prompted new research respirable dust characteristics. Between 2014 and 2015, 210 samples of respirable dust were collected in various locations of eight underground coal mines in three distinct Appalachian regions. The mines vary in terms of mining method, coal seam thickness, and mined strata geology. A computer-controlled SEM-EDX routine was used to analyze the dust to determine distributions of particle size, aspect ratio, and mineralogy classification. Statistical analysis of results showed that significant differences in dust characteristics exist between and within mine regions, and by sampling location. Most notably, samples from mid- and south-central Appalachia had relatively higher percentages of alumino-silicates and quartz, consistent with cutting more rock along with the coal in these mines; whereas, samples from northern Appalachia had higher percentages of carbonate, which is largely attributed to heavy rock dusting in the sampled mines. Compared to other regions, samples from mid-central Appalachia also had higher percentages of very small particles and samples from south-central Appalachia had higher percentages of elongated particles. Overall, samples collected near production activities or in return airways had higher percentages of small particles than in other sampling locations. Based on samples collected right at the mine face, results additionally suggest that cutting rock strata may produce an inordinate amount of respirable dust as compared to cutting coal.
Minerals
A recent resurgence in coal workers' pneumoconiosis (or "black lung") and concerns over other rel... more A recent resurgence in coal workers' pneumoconiosis (or "black lung") and concerns over other related respiratory illnesses have highlighted the need to elucidate characteristics of airborne particulates in occupational environments. A better understanding of particle size, aspect ratio, or chemical composition may offer new insights regarding causal factors of such illnesses. Scanning electron microscopy analysis using energy dispersive X-ray (SEM-EDX) can be used to estimate these particle characteristics. If conducted manually, such work can be very time intensive, limiting the number of particles that can be analyzed. Moreover, potential exists for user bias in interpretation of EDX spectra. A computer-controlled (CC) routine, on the other hand, can allow similar analysis at a much faster rate, increasing total particle counts and reproducibility of results. This paper describes a CCSEM-EDX routine specifically developed for analysis of respirable dust samples from coal mines. The routine is verified based on reliability of results obtained on samples of known materials, and reproducibility of results obtained on a set of 10 dust samples collected in the field. The characteristics of the field samples are also discussed with respect to mine occupational environments.
Journal of The Electrochemical Society, 2016
Flow electrification" occurs whenever a fluid passes along a charged surface, creating an electro... more Flow electrification" occurs whenever a fluid passes along a charged surface, creating an electrokinetic "streaming current" or "streaming potential' and is known to cause non-uniform corrosion (and other) problems in non-aqueous fluids. After observing unusual corrosion failures of copper in relatively low conductivity (≈150 μS/cm) potable water, a series of laboratory studies was conducted that verified flow electrification could also develop in aqueous systems and contribute to non-uniform corrosion. Relatively high direct streaming currents along pipelines were quantified in model systems with plastic dielectrics, which accelerated corrosion on the affected pipe section by up to 0.5 μA/cm 2 (assuming uniform corrosion). Very rapid non-uniform pipe failures (i.e., full wall penetration in 7 months) occurred in a system without dielectrics simulating a potable water recirculation system. The effects of flow electrification were virtually eliminated by addition of low levels of zinc phosphate, an inhibitor used in approximate 25% of potable water distribution systems. Flow electrification was also observed in plastic pipe systems with brass connectors.
Resources, 2015
A key consideration for responsible development of mineral and energy resources is the well-being... more A key consideration for responsible development of mineral and energy resources is the well-being of workers. Respirable dust in mining environments represents a serious concern for occupational health. In particular, coal miners can be exposed to a variety of dust characteristics depending on their work activities, and some exposures may pose risk for lung diseases like CWP and silicosis. As underscored by common regulatory frameworks, respirable dust exposures are generally characterized on the basis of total mass concentration, and also the silica mass fraction. However, relatively little emphasis has been placed on other dust characteristics that may be important in terms of identifying health risks. Comprehensive particle-level analysis to estimate chemistry, size, and shape distributions of particles is possible. This paper describes a standard methodology for characterization of respirable coal mine dust using scanning electron microscopy (SEM) with energy dispersive X-ray (EDX). Preliminary verification of the method is shown based several dust samples collected from an underground mine in Central Appalachia.