Mobility of Source Zone Heavy Metals and Radionuclides

Mobility of Source Zone Heavy Metals and Radionuclides PDF Author:
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ISBN:
Category :
Languages : en
Pages :

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Book Description
Predicting the potential migration of metals and radionuclides from waste pits and trenches will require understanding the effects of carbon and electron flow through these environments. Important aspects of this flow include the physiological activity of cellulolytic and non-cellulolytic fermentative microbial populations, as well as the subsequent activity of metal and radionuclide reducing bacteria. The activity of subsurface fermentative microbial populations is significantly understudied even though these organisms can affect contaminant migration by at least two mechanisms. In the first mechanism, products of the fermentation process can act as chelators for metals and radionuclides increasing their transport through underlying geological media. The second mechanism is the reduction and immobilization of metals and radionuclides since some fermentative bacteria have been shown to directly reduce metals and radionuclides, while their fermentation products can provide carbon and energy for respiratory metal reducing bacteria that can also reduce oxidized metals and radionuclides.

Mobility of Source Zone Heavy Metals and Radionuclides

Mobility of Source Zone Heavy Metals and Radionuclides PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
Predicting the potential migration of metals and radionuclides from waste pits and trenches will require understanding the effects of carbon and electron flow through these environments. Important aspects of this flow include the physiological activity of cellulolytic and non-cellulolytic fermentative microbial populations, as well as the subsequent activity of metal and radionuclide reducing bacteria. The activity of subsurface fermentative microbial populations is significantly understudied even though these organisms can affect contaminant migration by at least two mechanisms. In the first mechanism, products of the fermentation process can act as chelators for metals and radionuclides increasing their transport through underlying geological media. The second mechanism is the reduction and immobilization of metals and radionuclides since some fermentative bacteria have been shown to directly reduce metals and radionuclides, while their fermentation products can provide carbon and energy for respiratory metal reducing bacteria that can also reduce oxidized metals and radionuclides.

Mobility of Source Zone Heavy Metals and Radionuclides

Mobility of Source Zone Heavy Metals and Radionuclides PDF Author: Brent Peyton
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
Various U.S. Department of Energy (DOE) low and medium-level radioactive waste sites contain mixtures of heavy metals, radionuclides and assorted organic materials. Over time, water infiltrates the wastes, and releases metals and radionuclides causing transport into the surrounding environment. We propose that fermentative microorganisms are active in these sites and may control metal and radionuclide migration from source zones (Figure 1). The following overarching hypothesis will drive our research: 'Metals and radionuclides can be mobilized by infiltration of water into waste storage sites. Microbial communities of lignocellulose degrading and fermenting microorganisms present in the subsurface of contaminated DOE sites can significantly impact migration by directly reducing and immobilizing metals and radionuclides while degrading complex organic matter to low molecular weight organic compounds. These low molecular weight organic compounds can increase metal and radionuclide mobility by chelation (i.e., certain organic acids) or decrease mobility by stimulating respiratory metal reducing microorganisms.' The objective of our research is to determine the effect of carbon and energy flow through simulated waste environments on metal and radionuclide migration from waste pits and trenches across the DOE complex. Metals and radionuclides can be mobilized by infiltration of water into waste storage sites. Cellulolytic and non-cellulolytic fermentative microorganisms have been chosen as the focus of this research because their activity is a critical first step that we hypothesize will control subsequent fate and transport in contaminated natural systems. Microbial communities of lignocellulose degrading and fermenting microorganisms present in the subsurface of contaminated DOE sites can significantly impact migration by directly reducing and immobilizing metals and radionuclides while degrading complex organic matter to low molecular weight organic compounds. These low molecular weight organic acids and alcohols can increase metal and radionuclide mobility by chelation (i.e., certain organic acids) or decrease mobility by stimulating respiratory metal reducing microorganisms.

Mobility of Source Zone Heavy Metals and Radionuclides

Mobility of Source Zone Heavy Metals and Radionuclides PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 17

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Book Description
Various U.S. Department of Energy (DOE) low and medium-level radioactive waste sites contain mixtures of heavy metals, radionuclides and assorted organic materials. In addition, there are numerous sites around the world that are contaminated with a mixture of organic and inorganic contaminants. In most sites, over time, water infiltrates the wastes, and releases metals, radionuclides and other contaminants causing transport into the surrounding environment. We investigated the role of fermentative microorganisms in such sites that may control metal, radionuclide and organics migration from source zones. The project was initiated based on the following overarching hypothesis: Metals, radionuclides and other contaminants can be mobilized by infiltration of water into waste storage sites. Microbial communities of lignocellulose degrading and fermenting microorganisms present in the subsurface of contaminated DOE sites can significantly impact migration by directly reducing and immobilizing metals and radionuclides while degrading complex organic matter to low molecular weight organic compounds. These low molecular weight organic acids and alcohols can increase metal and radionuclide mobility by chelation (i.e., certain organic acids) or decrease mobility by stimulating respiratory metal reducing microorganisms. We demonstrated that fermentative organisms capable of affecting the fate of Cr6+, U6+ and trinitrotoluene can be isolated from organic-rich low level waste sites as well as from less organic rich subsurface environments. The mechanisms, pathways and extent of contaminant transformation depend on a variety of factors related to the type of organisms present, the aqueous chemistry as well as the geochemistry and mineralogy. This work provides observations and quantitative data across multiple scales that identify and predict the coupled effects of fermentative carbon and electron flow on the transport of radionuclides, heavy metals and organic contaminants in the subsurface; a primary concern of the DOE Environmental Remediation Science Division (ERSD) and Subsurface Geochemical Research (SBR) Program.

Radionuclides and Heavy Metals in Environment

Radionuclides and Heavy Metals in Environment PDF Author: Marina Marinova
Publisher: Springer Science & Business Media
ISBN: 9401009937
Category : Science
Languages : en
Pages : 412

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Book Description
This volume entitled "Radionuclides and Heavy Metals in Environment" contains the Proceedings of the NATO Advanced Research Workshop (ARW) "Monitoring of Natural and Man-Made Radionuclides and Heavy Metal Waste in Environment" that was held at the Joint Institute for Nuclear Research (JlNR), Dubna, Russia from 3 October to 6 October, 2000. Originally, it was planned to held the ARW in 1999, the year when NATO was celebrating its 50th anniversary. Few days before opening it had to be postponed because of problems in issuing visa for all the colleagues who intended to participate. The ARW was organized and conducted by the co-directors Prof. Vladimir P. Perelygin, Joint Institute for Nuclear Research, Dubna, Russia and Dr. Peter Vater, Philipps Universitat, Marburg, Germany. The JlNR was chosen as the host institute of ARW because of the lack of contact and real co-operation between the former Soviet Union (FSU) countries specialists in ecology and their Western well experienced colleagues. The selection of this location and supplementary funds provided by Russian Foundation on Basic Research, Moscow, Russia, and the JINR, Dubna., Russia made it possible to attain a rather large number of participants and observers from FSU countries. The JlNR provided to all the participants of the workshop an effective car/minibus transportation Moscow-Dubna-Moscow and a rather good accommodation in Dubna.

Behavior of Radionuclides in the Environment II

Behavior of Radionuclides in the Environment II PDF Author: Alexei Konoplev
Publisher: Springer Nature
ISBN: 981153568X
Category : Technology & Engineering
Languages : en
Pages : 447

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Book Description
This is Volume II in a three-volume set on the Behavior of Radionuclides in the Environment, focusing on Chernobyl. Now, so many years after the Chernobyl accident, new data is emerging and important new findings are being made. The book reviews major research achievements concerning the behavior of Chernobyl-derived radionuclides, including their air transport and resuspension, mobility and bioavailability in the soil-water environment, vertical and lateral migration in soils and sediments, soil-to-plant and soil-to-animal transfer, and water-to-aqueous biota transfer. The long-term dynamics of radionuclides in aquatic ecosystems are also discussed, in particular, the heavily contaminated cooling pond of the Chernobyl Nuclear Power Plant, which is in the process of being decommissioned. Lessons learned from long-term research on the environmental behavior of radionuclides can help us understand the pathways of environmental contamination, which, in turn, will allow us to improve methods for modeling and predicting the long-term effects of pollution. This book features a wealth of original data and findings, many of which have never been published before, or were not available internationally. The contributing authors are experts from Ukraine, Russia and Belarus with more than 30 years of experience investigating Chernobyl-derived radionuclides in the environment. The content presented here can help to predict the evolution of environmental contamination following a nuclear accident, and specifically the Fukushima Dai-ichi nuclear power plant accident.

Radionuclide Contamination and Remediation Through Plants

Radionuclide Contamination and Remediation Through Plants PDF Author: Dharmendra Kumar Gupta
Publisher: Springer
ISBN: 3319076655
Category : Science
Languages : en
Pages : 315

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Book Description
This book focuses on the mechanistic (microscopic) understanding of radionuclide uptake by plants in contaminated soils and potential use of phytoremediation. The key features concern radionuclide toxicity in plants, how the radioactive materials are absorbed by plants, and how the plants cope with the toxic responses. The respective chapters examine soil classification, natural plant selection, speciation of actinides, kinetic modeling, and case studies on cesium uptake after radiation accidents. Radionuclide contaminants pose serious problems for biological systems, due to their chemical toxicity and radiological effects. The processes by which radionuclides can be incorporated into vegetation can either originate from activity interception by external plant surfaces (either directly from the atmosphere or from resuspended material), or through uptake of radionuclides via the root system. Subsequent transfer of toxic elements to the human food chain is a concrete danger. Therefore, the molecular mechanisms and genetic basis of transport into and within plants needs to be understood for two reasons: The effectiveness of radionuclide uptake into crop plants – so-called transfer coefficient – is a prerequisite for the calculation of dose due to the food path. On the other hand, efficient radionuclide transfer into plants can be made use of for decontamination of land – so-called phytoremediation, the direct use of living, green plants for in situ removal of pollutants from the environment or to reduce their concentrations to harmless levels.

Biophysico-Chemical Processes of Heavy Metals and Metalloids in Soil Environments

Biophysico-Chemical Processes of Heavy Metals and Metalloids in Soil Environments PDF Author: Antonio Violante
Publisher: John Wiley & Sons
ISBN: 0470175478
Category : Science
Languages : en
Pages : 681

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Book Description
Written by a multidisciplinary group of soil and environmental scientists, Biophysico-Chemical Processes of Heavy Metals and Metalloids in Soil Environments provides the scientific community with a critical qualitative and quantitative review of the fundamentals of the processes of pollutants in soil environments. The book covers pollutants' speciation, mobility, bioavailability and toxicity, and impacts on development of innovative restoration strategies. In addition, the development of innovative remediation strategies for polluted soils is covered.

Phosphate in Soils

Phosphate in Soils PDF Author: H. Magdi Selim
Publisher: CRC Press
ISBN: 148223680X
Category : Nature
Languages : en
Pages : 381

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Book Description
Edited by One of the Best Specialists in Soil Science Recent studies reveal that Phosphorus (P) in the form of phosphate, a macronutrient essential for plant growth, and crop yields can influence the bioavailability, retention, and mobility of trace elements, metal(loid)s, and radio nuclides in soils. When this occurs, phosphates can affect the dynamics of heavy metals and influence soil characteristics, impacting soil mobility and toxicity. Phosphate in Soils: Interaction with Micronutrients, Radionuclides and Heavy Metals utilizes the latest research to emphasize the role that phosphate plays in enhancing or reducing the mobility of heavy metals in soil, and the soil-water-plant environment. It provides an in-depth understanding of each heavy metal species, and expands on phosphate interactions in geological material. Composed of 12 chapters, this text: Provides an overview of the reactions of metal(loid)s and common P compounds that are used as fertilizer in soils Emphasizes the effect of phosphorus on copper and zinc adsorption in acid soils Discusses findings on the influence of phosphate compounds on speciation, mobility, and bioavailability of heavy metals in soils as well as the role of phosphates on in situ and phytoremediation of heavy metals for contaminated soils Places emphasis on the influence of phosphate on various heavy metals species in soils, and their solubility/mobility and availability Provides extensive information on testing various high phosphate materials for remediation of heavy metal, micronutrients, and radionuclides contaminated sites Explores the reactivity of heavy metals, micronutrients and radionuclides elements in several soils Presents a case study illustrating various remediation efforts of acidic soils and remediation of Cu, Zn, and lead (Pb) contaminated soils around nonferrous industrial plants Emphasizes the significance of common ions (cations and anions) on phosphate mobility and sorption in soils, and more The author includes analytical and numerical solutions along with hands-on applications, and addresses other topics that include the transport and sorption modeling of heavy metals in the presence of phosphate at different scales in the vadose zone.

Radionuclides in the Environment

Radionuclides in the Environment PDF Author: Clemens Walther
Publisher: Springer
ISBN: 331922171X
Category : Science
Languages : en
Pages : 277

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Book Description
This book provides extensive and comprehensive information to researchers and academicians who are interested in radionuclide contamination, its sources and environmental impact. It is also useful for graduate and undergraduate students specializing in radioactive-waste disposal and its impact on natural as well as manmade environments. A number of sites are affected by large legacies of waste from the mining and processing of radioactive minerals. Over recent decades, several hundred radioactive isotopes (radioisotopes) of natural elements have been produced artificially, including 90Sr, 137Cs and 131I. Several other anthropogenic radioactive elements have also been produced in large quantities, for example technetium, neptunium, plutonium and americium, although plutonium does occur naturally in trace amounts in uranium ores. The deposition of radionuclides on vegetation and soil, as well as the uptake from polluted aquifers (root uptake or irrigation) are the initial point for their transfer into the terrestrial environment and into food chains. There are two principal deposition processes for the removal of pollutants from the atmosphere: dry deposition is the direct transfer through absorption of gases and particles by natural surfaces, such as vegetation, whereas showery or wet deposition is the transport of a substance from the atmosphere to the ground by snow, hail or rain. Once deposited on any vegetation, radionuclides are removed from plants by the airstre am and rain, either through percolation or by cuticular scratch. The increase in biomass during plant growth does not cause a loss of activity, but it does lead to a decrease in activity concentration due to effective dilution. There is also systemic transport (translocation) of radionuclides within the plant subsequent to foliar uptake, leading the transfer of chemical components to other parts of the plant that have not been contaminated directly.

Mobility of Heavy Metals in Aquatic Environments Impacted by Ancient Mining-Waste

Mobility of Heavy Metals in Aquatic Environments Impacted by Ancient Mining-Waste PDF Author: Mario Alfonso Murillo-Tovar
Publisher:
ISBN:
Category : Electronic books
Languages : en
Pages : 0

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Book Description
The mobility of heavy metals in aquatic environments, impacted by discharges from mining waste, is one of the major processes causing metal pollution mainly by arsenic (As), cadmium (Cd), lead (Pb), zinc (Zn) and iron (Fe), which could be risky for biota and human health. The heavy metals contained in mining waste constituted by large amounts of sulfides can reach the aquatic compartments by acid mine drainage and runoff and eventually become deposited in sediments and associated with colloidal material, being this one of the main reservoirs and ways of transport. However, the mobility of heavy metal is influenced by their specific chemical properties and undergo several physicochemical phenomena as sorption, oxidation,Äìreduction, hydrolysis and this can be influenced by water flow, the size and composition of geological material. Hence, this work aims to review the processes and mechanism involved in the fate and transport of heavy metals from mining-waste to aquatic compartments and the methods used for identification of the specific chemical species associated with their mobility and ecological risk.