The environmental effects of metal mining activity are receiving ever increasing attention from t... more The environmental effects of metal mining activity are receiving ever increasing attention from the public, regulators, land managers, and the mining industry. There are several issues currently of primary interest: (1) assessment and remediation of environmental problems at abandoned metal-mine sites; (2) prediction and mitigation (or prevention) of potential environmental effects from future mining activity; (3) determination of baseline conditions that existed in mineralized areas prior to mining (conditions which in many mineralized areas were naturally degraded) and; (4) development of effective, scientifically-realistic regulations to govern past, present, and future mining activity. This paper summarizes a GIS-based approach developed to help address these issues. Continually in refinement, our approach uses geologic and geochemical data layers to help estimate potential environmental impacts of metal-mining activities on surrounding watersheds. The approach is based on the fact that mineral-deposit geology as well as geochemical processes exert fundamental and predictable controls on the environmental conditions in mineralized areas prior to mining, and environmental conditions that result from mining and mineral processing. Similarly, the geologic and geochemical characteristics of the rock units in the watersheds surrounding mining districts and unmined mineralized areas can strongly influence the spatial extent and magnitude of environmental impacts on themore » surrounding watersheds. Results of prototype work in the State of Colorado are presented here with a focus on environmental effects on surface-water quality; however, the techniques are generally applicable, with appropriate changes in complexity of scale, for areas ranging in size from a single watershed to a large state and for other environmental effects such as smelter emissions and windblown solid contaminants. A second prototype for the State of Montana is currently under development.« less
The correlation of exposure to particulate matter (PM) and increased morbidity and mortality was ... more The correlation of exposure to particulate matter (PM) and increased morbidity and mortality was established in the 1970's. Research focused on elucidating mechanisms of action (i.e. particle size, composition, and biodurability), has generally examined anthropogenic sources such as solid or liquid combustion byproducts of fossil fuels, byproducts from the smelting of metal ores, and commercial/industrial mineral dusts (asbestos, crystalline silica. metal dusts). While many studies exist on agricultural exposures to inorganic dust, far fewer have examined health issues related to particulate matter contributions from rural, non-agricultural dusts or other geogenic sources. Geogenic PM (produced by natural processes such as volcanic ash, volcanic fog (vog), dusts from dry lakes or glacial deposits, smoke and windborne ash from wildfires, and dusts containing various soil pathogens) and geoanthropogenic PM (produced from natural sources by processes that are modified or enhanced by human activities such as dusts from lakebeds dried by human removal of water, dusts produced from areas that have undergone desertification as a result of human practices etc.) are increasingly recognized as potential agents of toxicity and disease, via both environmental and occupational exposures. Surface sediment on some dry lake beds may contribute significant amounts of mineral dusts to the atmospheric load. For example, Owens Lake (a dry lake in southern California) has been a major source of PM10 (particulate matter less than 10 micrometers) dust in the United States. Dusts from dry and drying saline lakes may contain high concentrations of metals, such as arsenic, with known human health toxicity. Wildfires, consuming over nine million acres in 2007, also contribute significant amounts of particulate matter in addition to their other hazards. Designed to estimate the bioaccessibility of metals in soils, dusts and other environmental materials by measuring the reactivity of the materials in simulated body fluids (SBFs), physiologically based extraction tests (PBETs) are an inexpensive, acellular in vitro test. Bioaccessibility, defined as the fraction of a potential toxicant that becomes soluble in the SBF (e.g. gastric, intestinal, lung or lysosomal fluid), is an indication of the amounts of a potential toxicant that may be available for absorption through ingestion or inhalation. PBETs were conducted on artificially generated dust samples from playas in the Mojave Desert and soil and ash samples from recent California wildfires. Speciation, an important factor in assessing toxicity, was evaluated using high performance liquid chromatography (HPLC) separation with ICP-MS detection for arsenic and chromium.
Disasters commonly pose immediate threats to human safety, but can also produce hazardous materia... more Disasters commonly pose immediate threats to human safety, but can also produce hazardous materials (HM) that pose short- and long-term environmental-health threats. The U.S. Geological Survey (USGS) has helped assess potential environmental health characteristics of HM produced by various natural and anthropogenic disasters, such as the 2001 World Trade Center collapse, 2005 hurricanes Katrina and Rita, 2007-2009 southern California wildfires,
ABSTRACT History abounds with accounts of cities that were destroyed or significantly damaged by ... more ABSTRACT History abounds with accounts of cities that were destroyed or significantly damaged by natural or anthropogenic disasters, such as volcanic eruptions, earthquakes, wildland–urban wildfires, hurricanes, tsunamis, floods, urban firestorms, terrorist attacks, and armed conflicts. Burgeoning megacities place ever more people in the way of harm from future disasters. In addition to the physical damage, casualties, and injuries they cause, sudden urban disasters can also release into the environment large volumes of potentially hazardous materials. Environmental and medical geochemistry investigations help us to (1) understand the sources and environmental behavior of disaster materials, (2) assess potential threats the materials pose to the urban environment and health of urban populations, (3) develop strategies for their cleanup/disposal, and (4) anticipate and mitigate potential environmental and health effects from future urban disasters.
ABSTRACT Many natural or human-caused disasters release potentially hazardous materials (HM) that... more ABSTRACT Many natural or human-caused disasters release potentially hazardous materials (HM) that may pose threats to the environment and health of exposed humans, wildlife, and livestock. This chapter summarizes the environmentally and toxicologically significant physical, mineralogical, and geochemical characteristics of materials produced by a wide variety of recent disasters, such as volcanic eruptions, hurricanes and extreme storms, spills of mining/mineral-processing wastes or coal extraction by-products, and the 2001 attacks on and collapse of the World Trade Center towers. In describing these characteristics, this chapter also illustrates the important roles that geochemists and other earth scientists can play in environmental disaster response and preparedness. In addition to characterizing in detail the physical, chemical, and microbial makeup of HM generated by the disasters, these roles also include (1) identifying and discriminating potential multiple sources of the materials; (2) monitoring, mapping, and modeling dispersal and evolution of the materials in the environment; (3) understanding how the materials are modified by environmental processes; (4) identifying key characteristics and processes that influence the materials' toxicity to exposed humans and ecosystems; (5) estimating shifts away from predisaster environmental baseline conditions; and (6) using geochemical insights learned from past disasters to help estimate, prepare for, and increase societal resilience to the environmental and related health impacts of future disasters.
ABSTRACT Available for download at http://www.sciencedirect.com/science/book/9780123842459. We de... more ABSTRACT Available for download at http://www.sciencedirect.com/science/book/9780123842459. We describe several applications of geochemical modeling to study metal sorption in a number of mine-drainage systems. As a validation exercise, the computer model MINTEQA2, coupled with the Generalized Two-Layer Model for sorption reactions, was successfully used to simulate results from batch pH-dependent sorption experiments with natural water and iron-rich sediment from a mine-drainage system. Based on this validation exercise, the model was then used to examine metal sorption onto suspended iron-rich particulates in several geologically and geochemically diverse mine-drainage systems. We conclude that metal partitioning in iron-rich mine-drainage systems can be approximated by assuming that iron-rich suspended sediment primarily controls sorption reactions and that sorption onto bed sediment plays a decidedly secondary role. Finally, we present a modeling approach that can determine the self-mitigating capacity of mine drainage and we demonstrate that sorption reactions in the water column can be exploited in the mitigation and remediation of some mine-drainage problems.
ABSTRACT It is generally accepted that exposure to fine particulate matter may increase risk for ... more ABSTRACT It is generally accepted that exposure to fine particulate matter may increase risk for human morbidity and mortality. Until recently, population health related studies examining the effects of particulate matter on human health generally examined anthropogenic (industry and combustion by-products) sources with few studies considering contributions from natural sources. This chapter provides an overview of naturally occurring inorganic mineral dust research and associated human health ailments and some of the challenges in elucidating the etiological mechanisms responsible.
The environmental effects of metal mining activity are receiving ever increasing attention from t... more The environmental effects of metal mining activity are receiving ever increasing attention from the public, regulators, land managers, and the mining industry. There are several issues currently of primary interest: (1) assessment and remediation of environmental problems at abandoned metal-mine sites; (2) prediction and mitigation (or prevention) of potential environmental effects from future mining activity; (3) determination of baseline conditions that existed in mineralized areas prior to mining (conditions which in many mineralized areas were naturally degraded) and; (4) development of effective, scientifically-realistic regulations to govern past, present, and future mining activity. This paper summarizes a GIS-based approach developed to help address these issues. Continually in refinement, our approach uses geologic and geochemical data layers to help estimate potential environmental impacts of metal-mining activities on surrounding watersheds. The approach is based on the fact that mineral-deposit geology as well as geochemical processes exert fundamental and predictable controls on the environmental conditions in mineralized areas prior to mining, and environmental conditions that result from mining and mineral processing. Similarly, the geologic and geochemical characteristics of the rock units in the watersheds surrounding mining districts and unmined mineralized areas can strongly influence the spatial extent and magnitude of environmental impacts on themore » surrounding watersheds. Results of prototype work in the State of Colorado are presented here with a focus on environmental effects on surface-water quality; however, the techniques are generally applicable, with appropriate changes in complexity of scale, for areas ranging in size from a single watershed to a large state and for other environmental effects such as smelter emissions and windblown solid contaminants. A second prototype for the State of Montana is currently under development.« less
The correlation of exposure to particulate matter (PM) and increased morbidity and mortality was ... more The correlation of exposure to particulate matter (PM) and increased morbidity and mortality was established in the 1970's. Research focused on elucidating mechanisms of action (i.e. particle size, composition, and biodurability), has generally examined anthropogenic sources such as solid or liquid combustion byproducts of fossil fuels, byproducts from the smelting of metal ores, and commercial/industrial mineral dusts (asbestos, crystalline silica. metal dusts). While many studies exist on agricultural exposures to inorganic dust, far fewer have examined health issues related to particulate matter contributions from rural, non-agricultural dusts or other geogenic sources. Geogenic PM (produced by natural processes such as volcanic ash, volcanic fog (vog), dusts from dry lakes or glacial deposits, smoke and windborne ash from wildfires, and dusts containing various soil pathogens) and geoanthropogenic PM (produced from natural sources by processes that are modified or enhanced by human activities such as dusts from lakebeds dried by human removal of water, dusts produced from areas that have undergone desertification as a result of human practices etc.) are increasingly recognized as potential agents of toxicity and disease, via both environmental and occupational exposures. Surface sediment on some dry lake beds may contribute significant amounts of mineral dusts to the atmospheric load. For example, Owens Lake (a dry lake in southern California) has been a major source of PM10 (particulate matter less than 10 micrometers) dust in the United States. Dusts from dry and drying saline lakes may contain high concentrations of metals, such as arsenic, with known human health toxicity. Wildfires, consuming over nine million acres in 2007, also contribute significant amounts of particulate matter in addition to their other hazards. Designed to estimate the bioaccessibility of metals in soils, dusts and other environmental materials by measuring the reactivity of the materials in simulated body fluids (SBFs), physiologically based extraction tests (PBETs) are an inexpensive, acellular in vitro test. Bioaccessibility, defined as the fraction of a potential toxicant that becomes soluble in the SBF (e.g. gastric, intestinal, lung or lysosomal fluid), is an indication of the amounts of a potential toxicant that may be available for absorption through ingestion or inhalation. PBETs were conducted on artificially generated dust samples from playas in the Mojave Desert and soil and ash samples from recent California wildfires. Speciation, an important factor in assessing toxicity, was evaluated using high performance liquid chromatography (HPLC) separation with ICP-MS detection for arsenic and chromium.
Disasters commonly pose immediate threats to human safety, but can also produce hazardous materia... more Disasters commonly pose immediate threats to human safety, but can also produce hazardous materials (HM) that pose short- and long-term environmental-health threats. The U.S. Geological Survey (USGS) has helped assess potential environmental health characteristics of HM produced by various natural and anthropogenic disasters, such as the 2001 World Trade Center collapse, 2005 hurricanes Katrina and Rita, 2007-2009 southern California wildfires,
ABSTRACT History abounds with accounts of cities that were destroyed or significantly damaged by ... more ABSTRACT History abounds with accounts of cities that were destroyed or significantly damaged by natural or anthropogenic disasters, such as volcanic eruptions, earthquakes, wildland–urban wildfires, hurricanes, tsunamis, floods, urban firestorms, terrorist attacks, and armed conflicts. Burgeoning megacities place ever more people in the way of harm from future disasters. In addition to the physical damage, casualties, and injuries they cause, sudden urban disasters can also release into the environment large volumes of potentially hazardous materials. Environmental and medical geochemistry investigations help us to (1) understand the sources and environmental behavior of disaster materials, (2) assess potential threats the materials pose to the urban environment and health of urban populations, (3) develop strategies for their cleanup/disposal, and (4) anticipate and mitigate potential environmental and health effects from future urban disasters.
ABSTRACT Many natural or human-caused disasters release potentially hazardous materials (HM) that... more ABSTRACT Many natural or human-caused disasters release potentially hazardous materials (HM) that may pose threats to the environment and health of exposed humans, wildlife, and livestock. This chapter summarizes the environmentally and toxicologically significant physical, mineralogical, and geochemical characteristics of materials produced by a wide variety of recent disasters, such as volcanic eruptions, hurricanes and extreme storms, spills of mining/mineral-processing wastes or coal extraction by-products, and the 2001 attacks on and collapse of the World Trade Center towers. In describing these characteristics, this chapter also illustrates the important roles that geochemists and other earth scientists can play in environmental disaster response and preparedness. In addition to characterizing in detail the physical, chemical, and microbial makeup of HM generated by the disasters, these roles also include (1) identifying and discriminating potential multiple sources of the materials; (2) monitoring, mapping, and modeling dispersal and evolution of the materials in the environment; (3) understanding how the materials are modified by environmental processes; (4) identifying key characteristics and processes that influence the materials' toxicity to exposed humans and ecosystems; (5) estimating shifts away from predisaster environmental baseline conditions; and (6) using geochemical insights learned from past disasters to help estimate, prepare for, and increase societal resilience to the environmental and related health impacts of future disasters.
ABSTRACT Available for download at http://www.sciencedirect.com/science/book/9780123842459. We de... more ABSTRACT Available for download at http://www.sciencedirect.com/science/book/9780123842459. We describe several applications of geochemical modeling to study metal sorption in a number of mine-drainage systems. As a validation exercise, the computer model MINTEQA2, coupled with the Generalized Two-Layer Model for sorption reactions, was successfully used to simulate results from batch pH-dependent sorption experiments with natural water and iron-rich sediment from a mine-drainage system. Based on this validation exercise, the model was then used to examine metal sorption onto suspended iron-rich particulates in several geologically and geochemically diverse mine-drainage systems. We conclude that metal partitioning in iron-rich mine-drainage systems can be approximated by assuming that iron-rich suspended sediment primarily controls sorption reactions and that sorption onto bed sediment plays a decidedly secondary role. Finally, we present a modeling approach that can determine the self-mitigating capacity of mine drainage and we demonstrate that sorption reactions in the water column can be exploited in the mitigation and remediation of some mine-drainage problems.
ABSTRACT It is generally accepted that exposure to fine particulate matter may increase risk for ... more ABSTRACT It is generally accepted that exposure to fine particulate matter may increase risk for human morbidity and mortality. Until recently, population health related studies examining the effects of particulate matter on human health generally examined anthropogenic (industry and combustion by-products) sources with few studies considering contributions from natural sources. This chapter provides an overview of naturally occurring inorganic mineral dust research and associated human health ailments and some of the challenges in elucidating the etiological mechanisms responsible.
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Papers by Geoffrey Plumlee