Barbara J Mahler (Former Employee)
Science and Products
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Volatile organic compound and pesticide data in public water-supply reservoirs and wells, Texas, 1999-2001
To provide data for the Texas Source-Water Assessment and Protection Program, the U.S. Geological Survey conducted a synoptic survey of 48 public water-supply reservoirs and 174 public water-supply wells during 1999–2001. The surface-water samples were analyzed for volatile organic compounds and soluble pesticides. The ground-water samples were analyzed for volatile organic compounds and soluble p
Authors
Barbara Mahler, M.O. Gary, M.G. Canova, Eric W. Strom, Lynne Fahlquist, Michael E. Dorsey
Effects of oil and gas production on Lake Meredith sediments, 1964-99
Lake Meredith lies on the dry and windswept High Plains of the Texas Panhandle and is a popular recreation area for the region. Oil and gas exploration and extraction have been ongoing at Lake Meredith National Recreation Area since about 1930. More than 250 wells, including those abandoned or relocated, are within the boundaries of the recreation area. Oil and gas wells in the watershed of Lake M
Authors
Barbara Mahler, Peter C. Van Metre
Determining the occurrence of pesticides and volatile organic compounds in public water-supply source waters in Texas
No abstract available.
Authors
B.J. Mahler
Urban sprawl leaves its PAH signature
The increasing vehicle traffic associated with urban sprawl in the United States is frequently linked to degradation of air quality, but its effect on aquatic sediment is less well-recognized. This study evaluates trends in PAHs, a group of contaminants with multiple urban sources, in sediment cores from 10 reservoirs and lakes in six U.S. metropolitan areas. The watersheds chosen represent a rang
Authors
P. C. Van Metre, B.J. Mahler, E. T. Furlong
Transport of free and particulate-associated bacteria in karst
Karst aquifers, because of their unique hydrogeologic characteristics, are extremely susceptible to contamination by pathogens. Here we present the results of an investigation of contamination of a karst aquifer by fecal indicator bacteria. Two wells intercepting zones with contrasting effective hydraulic conductivities, as determined by pump test, were monitored both during the dry season and in
Authors
B.J. Mahler, J.-C. Personne, G.F. Lods, C. Drogue
Mobile sediment in an urbanizing karst aquifer: Implications for contaminant transport
Here we investigate geochemical characteristics of sediment in different compartments of a karst aquifer and demonstrate that mobile sediments in a karst aquifer can exhibit a wide range of properties affecting their contaminant transport potential. Sediment samples were collected from surface streams, sinkholes, caves, wells, and springs of a karst aquifer (the Barton Springs portion of the Edwar
Authors
B.J. Mahler, L. Lynch, P.C. Bennett
Town Lake bottom sediments : a chronicle of water quality changes in Austin, Texas, 1960-98
Town Lake, the last in the chain of Highland Lakes on the Colorado River, runs through the center of Austin, Texas. On any given day, grebes and coots dot the water, rowers skim alongside, and the sparkle of the sun on the water can be admired from the adjacent hike and bike path and from the windows of nearby office buildings. During the summer months, crowds gather along the shores of Town Lake
Authors
Peter C. Van Metre, B.J. Mahler
Water quality in the Trinity River basin, Texas, 1992-95
Water quality in the Trinity River basin was studied during 1992-95 as part of the USGS National Water-Quality Assessment (NAWQA) Program. Studies included chemical sampling of streams, streambed sediments, biota, and ground water; measuring distributions of biological communities in streams; and measuring physical characteristics of streams that affect biological habitat. The sampling design, in
Authors
Larry F. Land, J. Bruce Moring, Peter C. Van Metre, David C. Reutter, Barbara Mahler, Allison A. Shipp, Randy L. Ulery
DNA-labeled clay: A sensitive new method for tracing particle transport
The behavior of mobile colloids and sediment in most natural environments remains poorly understood, in part because characteristics of existing sediment tracers limit their widespread use. Here we describe the development of a new approach that uses a DNA-labeled montmorillonite clay as a highly sensitive and selective sediment tracer that can potentially characterize sediment and colloid transpo
Authors
B.J. Mahler, M. Winkler, P. Bennett, D.M. Hillis
Lanthanide-labeled clay: A new method for tracing sediment transport in Karst
Mobile sediment is a fundamental yet poorly characterized aspect of mass transport through karst aquifers. Here the development and field testing of an extremely sensitive particle tracer that may be used to characterize sediment transport in karst aquifers is described. The tracer consists of micron-size montmorillonite particles homoionized to the lanthanide form; after injection and retrieval f
Authors
B.J. Mahler, P.C. Bennett, M. Zimmerman
Science and Products
Filter Total Items: 13
No Result Found
Filter Total Items: 24
No results found.
Filter Total Items: 106
Volatile organic compound and pesticide data in public water-supply reservoirs and wells, Texas, 1999-2001
To provide data for the Texas Source-Water Assessment and Protection Program, the U.S. Geological Survey conducted a synoptic survey of 48 public water-supply reservoirs and 174 public water-supply wells during 1999–2001. The surface-water samples were analyzed for volatile organic compounds and soluble pesticides. The ground-water samples were analyzed for volatile organic compounds and soluble p
Authors
Barbara Mahler, M.O. Gary, M.G. Canova, Eric W. Strom, Lynne Fahlquist, Michael E. Dorsey
Effects of oil and gas production on Lake Meredith sediments, 1964-99
Lake Meredith lies on the dry and windswept High Plains of the Texas Panhandle and is a popular recreation area for the region. Oil and gas exploration and extraction have been ongoing at Lake Meredith National Recreation Area since about 1930. More than 250 wells, including those abandoned or relocated, are within the boundaries of the recreation area. Oil and gas wells in the watershed of Lake M
Authors
Barbara Mahler, Peter C. Van Metre
Determining the occurrence of pesticides and volatile organic compounds in public water-supply source waters in Texas
No abstract available.
Authors
B.J. Mahler
Urban sprawl leaves its PAH signature
The increasing vehicle traffic associated with urban sprawl in the United States is frequently linked to degradation of air quality, but its effect on aquatic sediment is less well-recognized. This study evaluates trends in PAHs, a group of contaminants with multiple urban sources, in sediment cores from 10 reservoirs and lakes in six U.S. metropolitan areas. The watersheds chosen represent a rang
Authors
P. C. Van Metre, B.J. Mahler, E. T. Furlong
Transport of free and particulate-associated bacteria in karst
Karst aquifers, because of their unique hydrogeologic characteristics, are extremely susceptible to contamination by pathogens. Here we present the results of an investigation of contamination of a karst aquifer by fecal indicator bacteria. Two wells intercepting zones with contrasting effective hydraulic conductivities, as determined by pump test, were monitored both during the dry season and in
Authors
B.J. Mahler, J.-C. Personne, G.F. Lods, C. Drogue
Mobile sediment in an urbanizing karst aquifer: Implications for contaminant transport
Here we investigate geochemical characteristics of sediment in different compartments of a karst aquifer and demonstrate that mobile sediments in a karst aquifer can exhibit a wide range of properties affecting their contaminant transport potential. Sediment samples were collected from surface streams, sinkholes, caves, wells, and springs of a karst aquifer (the Barton Springs portion of the Edwar
Authors
B.J. Mahler, L. Lynch, P.C. Bennett
Town Lake bottom sediments : a chronicle of water quality changes in Austin, Texas, 1960-98
Town Lake, the last in the chain of Highland Lakes on the Colorado River, runs through the center of Austin, Texas. On any given day, grebes and coots dot the water, rowers skim alongside, and the sparkle of the sun on the water can be admired from the adjacent hike and bike path and from the windows of nearby office buildings. During the summer months, crowds gather along the shores of Town Lake
Authors
Peter C. Van Metre, B.J. Mahler
Water quality in the Trinity River basin, Texas, 1992-95
Water quality in the Trinity River basin was studied during 1992-95 as part of the USGS National Water-Quality Assessment (NAWQA) Program. Studies included chemical sampling of streams, streambed sediments, biota, and ground water; measuring distributions of biological communities in streams; and measuring physical characteristics of streams that affect biological habitat. The sampling design, in
Authors
Larry F. Land, J. Bruce Moring, Peter C. Van Metre, David C. Reutter, Barbara Mahler, Allison A. Shipp, Randy L. Ulery
DNA-labeled clay: A sensitive new method for tracing particle transport
The behavior of mobile colloids and sediment in most natural environments remains poorly understood, in part because characteristics of existing sediment tracers limit their widespread use. Here we describe the development of a new approach that uses a DNA-labeled montmorillonite clay as a highly sensitive and selective sediment tracer that can potentially characterize sediment and colloid transpo
Authors
B.J. Mahler, M. Winkler, P. Bennett, D.M. Hillis
Lanthanide-labeled clay: A new method for tracing sediment transport in Karst
Mobile sediment is a fundamental yet poorly characterized aspect of mass transport through karst aquifers. Here the development and field testing of an extremely sensitive particle tracer that may be used to characterize sediment transport in karst aquifers is described. The tracer consists of micron-size montmorillonite particles homoionized to the lanthanide form; after injection and retrieval f
Authors
B.J. Mahler, P.C. Bennett, M. Zimmerman