We present an experimental approach for investigating the potential for bioremediation of Ž . volatile organic compounds VOCs in fractured rock vadose zones. The experimental work was performed with rock samples and indigenous microorganisms from the site of the United States Ž . Department of Energy’s Idaho National Engineering and Environmental Laboratory INEEL , located in a basalt flow basi...

Subsurface fate and transport models are utilized to predict concentrations of chemicals leaching from wastes into downgradient receptor wells. The contaminant concentrations in groundwater provide a measure of the risk to human health and the environment. The level of potential risk is currently used by the U.S. Environmental Protection Agency to determine whether management of the wastes shou...

One of the main problems associated with remediation of chlorinated solvent groundwater contamination is the presence of NAPLs in the source zone. NAPLs are often better treated through solvent extraction, surfactant washing, or vapor extraction than through bioremediation. Removal of NAPL through solvent extraction would likely leave a substantial residual of both the extraction solvent and th...

The release of nonaqueous phase liquids (NAPLs) to the subsurface environment can create long-term sources of ground water contamination as the NAPL slowly dissolves into ground water (Mercer and Cohen 1990; Cohen and Mercer 1993). Effective remediation of subsurface NAPL contamination requires that NAPL be accurately located and saturations quantified. This is particularly important for dense ...

The use of well-characterized porous media can simplify and improve the efficiency of laboratory subsurface flow and transport experiments. The objective of this study was to present a comprehensive set of hydrologically relevant properties for a unique set of commercially available silica sands. Features of sands selected for characterization included high sphericity, high batch-to-batch consi...

Studying large numbers of subjects in psychiatric neuroimaging research is often necessary to generate sufficient statistical power to reveal more subtle differences missed insmalleranalysesandtoallowsubtypinginwhatareoften heterogeneous diagnostic groups. Such an approach is probably essential in the case of clinical studies dealing with groups that are difficult to recruit from a single site ...

the same mathematical form, regardless of the nature and number of fluid components and phases. MULNumerical simulation has become a widely practiced and accepted KOM was a research code that served as a test bed for technique for studying flow and transport processes in the vadose developing much of the approaches and methodology zone and other subsurface flow systems. This article discusses a...

not available. Determining and Mapping DNAPL Saturation Values from Noninvasive GPR Measurements Sneddon, K.W. and G.R. Olhoeft (Colorado School of Mines, Golden); M.H. Powers (U.S. Geological Survey, Denver, CO). SAGEEP 2000: Symposium on Application of Geophysics to Environmental and Engineering Problems, 21-25 February 2000, Arlington, VA. Environmental and Engineering Geophysical Society, W...