Download or read book Effects of Redox Potentail on the Speciation of Selenium in Ground Water and Coal mine Backfill Materials Wyoming written by Katta Jayaram Reddy and published by . This book was released on 1995 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geochemical Processes and the Effects of Natural Organic Solutes on the Solubility of Selenium in Coal mine Backfill Samples from the Powder River Basin Wyoming written by and published by . This book was released on 1995 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Water resources Investigations Report written by and published by . This book was released on 1995 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Publications of the Geological Survey written by Geological Survey (U.S.) and published by . This book was released on 2000 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Influence of Redox Potential on Selenium Distribution in Ground Water Mendota Western San Joaquin Valley California written by Geological Survey (U.S.) and published by . This book was released on 1990 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Publications of the U S Geological Survey written by and published by . This book was released on 2000 with total page 646 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Agronomy Abstracts written by and published by . This book was released on 1993 with total page 976 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes abstracts of the annual meetings of the American Society of Agronomy; Soil Science Society of America; Crop Science Society of America ( - of its Agronomic Education Division).
Download or read book Geochemical Processes Affecting the Mobility of Dissolved Selenium in Surface Coal Mine Backfill Environments written by A. A. Fadlelmawla and published by . This book was released on 1994 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Speciation of Selenium in Groundwater written by Joan A. Oppenheimer and published by . This book was released on 1984 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selenium Transformation in Coal Mine Spoils written by and published by . This book was released on 1991 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this program was to conduct an environmental impact assessment study for selenium from coal mine spoils. The use of in-situ lysimetry to predict selenium speciation, transformation, and mobility under natural conditions was evaluated. The scope of the study was to construct and test field-scale lysimeter and laboratory mini-column to assess mobility and speciation of selenium in coal mine overburden and soil systems; to conduct soil and groundwater sampling throughout the state of Oklahoma for an overall environmental impact assessment of selenium; and to conduct an in-depth literature review on the solubility, speciation, mobility, and toxicity of selenium from various sources. Groundwater and surface soil samples were also collected from each county in Oklahoma. Data collected from the lysimeter study indicated that selenium in the overburden of the abandoned mine site was mainly found in the selenite form. The amount of selenite found was too low and immobile to be of concern to the environment. The spoil had equilibrated long enough (over 50 years) that most of the soluble forms of selenium have already been lost. Examination of the overburden indicated the presence of pyrite crystals that precipitated over time. The laboratory mini-column study indicated that selenite is quite immobile and remained on the overburden material even after leaching with dilute acid. Data from groundwater samples indicated that based on the current permissible level for selenium in groundwater (0.01 mg Se/L), Oklahoma groundwater is widely contaminated with the element. However, according to the new regulation (0.05 mg Se/L), which is to be promulgated in 1992, only 9 of the 77 counties in the state exceed the limit.
Download or read book Selenium Transformation in Coal Mine Spoils written by and published by . This book was released on 1991 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this program was to conduct an environmental impact assessment study for selenium from coal mine spoils. The use of in-situ lysimetry to predict selenium speciation, transformation, and mobility under natural conditions was evaluated. The scope of the study was to construct and test field-scale lysimeter and laboratory mini-column to assess mobility and speciation of selenium in coal mine overburden and soil systems; to conduct soil and groundwater sampling throughout the state of Oklahoma for an overall environmental impact assessment of selenium; and to conduct an in-depth literature review on the solubility, speciation, mobility, and toxicity of selenium from various sources. Groundwater and surface soil samples were also collected from each county in Oklahoma. Data collected from the lysimeter study indicated that selenium in the overburden of the abandoned mine site was mainly found in the selenite form. The amount of selenite found was too low and immobile to be of concern to the environment. The spoil had equilibrated long enough (over 50 years) that most of the soluble forms of selenium have already been lost. Examination of the overburden indicated the presence of pyrite crystals that precipitated over time. The laboratory mini-column study indicated that selenite is quite immobile and remained on the overburden material even after leaching with dilute acid. Data from groundwater samples indicated that based on the current permissible level for selenium in groundwater (0.01 mg Se/L), Oklahoma groundwater is widely contaminated with the element. However, according to the new regulation (0.05 mg Se/L), which is to be promulgated in 1992, only 9 of the 77 counties in the state exceed the limit.
Download or read book Selenite and Selenate Determination in Surface Coal Mine Backfill Ground Water written by Katta Jayaram Reddy and published by . This book was released on 1995 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Speciation of Selenium in Groundwater written by J. A. Oppenheimer and published by . This book was released on 1985 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Speciation of Selenium in Groundwater written by J. A. Oppenheimer and published by . This book was released on 1984 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Role of Natural Organic Solutes on the Sorption of Selenium by Coal Mine Backfill core Samples from the Powder River Basin Wyoming written by George F. Vance and published by . This book was released on 1995 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Placement Assessment and Monitoring in Reclaimed Environments of Materials Containing Selenium written by Joint Selenium Task Force (Wyo.) and published by . This book was released on 1994 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of a cooperative effort between the Wyoming Dept. of Environmental Quality, members of the Wyoming Mining Association, University of Wyoming, and the U.S. Geological Survey.
Download or read book Selenium Speciation Along a Groundwater Flow Path in the Carrizo Aquifer Southeastern Texas USA written by Rituparna Basu and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Selenium concentration and speciation [Se (VI), Se (IV) and Se ( -II)] was determined along a flow path in the Carrizo Sand aquifer (southeastern Texas). Groundwater sampling was carried out in March 2006, from ten wells located along the flow path. The collected samples were filtered through 0.45 mum filters and then acidified to pH 2 using ultra pure HCl. Analysis for Se concentration and speciation was done using selective hydride generation - Atomic Absorption spectrometry (HG-AAS). Additional in situ measurements from each well included determination of pH, alkalinity, oxidation-reduction potential (Eh in mV), dissolved iron speciation, dissolved sulfide concentrations and dissolved manganese concentrations. Selenium concentrations in groundwaters of the Carrizo Sand aquifer are very low (i.e., nanomolal concentrations). Variations in redox condition and geochemical processes appear to exert important controls on the distribution of Se species in Carrizo groundwaters. Redox conditions fluctuate between oxic to mildly reducing environment, in regions proximal to the recharge zone (i.e. & sim;0-15 km). Downgradient at a distance of 15-41 km, Fe (III) reduction is the dominant process, which is followed by sulfate reduction dominating at a distance41 km along the flow path. Se (VI) and Se ( -II) show variable behavior in regions near the recharge zone, whereas Se (IV) dominates in this region. (Abstract shortened by UMI.).
