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Acute toxicity of runoff from sealcoated pavement to Ceriodaphnia dubia and Pimephales promelas
Barbara J. Mahler, Christopher G. Ingersoll, Peter C. VanMetre, James L. Kunz, Edward E. Little
2015, Environmental Science and Technology (49) 5060-5069

Runoff from coal-tar-based (CT) sealcoated pavement is a source of polycyclic aromatic hydrocarbons (PAHs) and N-heterocycles to surface waters. We investigated acute toxicity of simulated runoff collected from 5 h to 111 days after application of CT sealcoat and from 4 h to 36 days after application of asphalt-based sealcoat containing...

Exposure to runoff from coal-tar-sealed pavement induces genotoxicity and impairment of DNA repair capacity in the RTL-W1 fish liver cell line
Aude Kienzler, Barbara J. Mahler, Peter C. VanMetre, Nathalie Schweigert, Alain Devaux, Sylvie Bony
2015, Science of the Total Environment (520) 73-80

Coal-tar-based (CTB) sealcoat, frequently applied to parking lots and driveways in North America, contains elevated concentrations of polycyclic aromatic hydrocarbons (PAHs) and related compounds. The RTL-W1 fish liver cell line was used to investigate two endpoints (genotoxicity and DNA-repair-capacity impairment) associated with exposure to runoff from asphalt pavement with CTB...

Lithologic and hydrologic controls of mixed alluvial-bedrock channels in flood-prone fluvial systems: bankfull and macrochannels in the Llano River watershed, central Texas, USA
Frank T. Heitmuller, Paul F. Hudson, William H. Asquith
2015, Geomorphology (232) 1-19

The rural and unregulated Llano River watershed located in central Texas, USA, has a highly variable flow regime and a wide range of instantaneous peak flows. Abrupt transitions in surface lithology exist along the main-stem channel course. Both of these characteristics afford an opportunity to examine hydrologic, lithologic, and sedimentary...

Data and spatial studies of the USGS Texas Water Science Center
Thomas E. Burley
2014, Fact Sheet 2014-3117

Hydrologists, geographers, geophysicists, and geologists with the U.S. Geological Survey (USGS) Texas Water Science Center (TXWSC) work in the USGS Water Mission Area on a diverse range of projects built on a foundation of spatial data. The TXWSC has developed sophisticated data and spatial-studies-related capabilities that are an integral part...

Abundance of host fish and frequency of glochidial parasitism in fish assessed in field and laboratory settings and frequency of juvenile mussels or glochidia recovered from hatchery-held fish, central and southeastern Texas, 2012-13
Christopher L. Braun, Charrish L. Stevens, Patricia D. Echo-Hawk, Nathan A. Johnson, James B. Moring
2014, Scientific Investigations Report 2014-5217

In 2012–13, the U.S. Geological Survey (USGS), in cooperation with the U.S. Fish and Wildlife Service (USFWS), completed the first phase of a two-phase study of mussel host-fish relations for five endemic mussel species in central and southeastern Texas that were State-listed as threatened on January 17, 2010: (1) Texas...

Geospatial compilation of historical water-level changes in the Chicot and Evangeline aquifers 1977-2013 and Jasper aquifer 2000-13, Gulf Coast aquifer system, Houston-Galveston region, Texas
Michaela R. Johnson, Joshua I. Linard
2014, Data Series 900

The U.S. Geological Survey (USGS) in cooperation with the Harris-Galveston Subsidence District, City of Houston, Fort Bend Subsidence District, Lone Star Groundwater Conservation District, and Brazoria County Groundwater Conservation District has produced an annual series of reports that depict water-level changes in the Chicot, Evangeline, and Jasper aquifers of the...

Simulation of hydrologic conditions and suspended-sediment loads in the San Antonio River Basin downstream from San Antonio, Texas, 2000-12
John R. Banta, Darwin J. Ockerman
2014, Scientific Investigations Report 2014-5182

Suspended sediment in rivers and streams can play an important role in ecological health of rivers and estuaries and consequently is an important issue for water-resource managers. To better understand suspended-sediment loads and transport in a watershed, the U.S. Geological Survey (USGS), in cooperation with the San Antonio River Authority, developed a...

Water quality of the Ogallala Formation, central High Plains aquifer within the North Plains Groundwater Conservation District, Texas Panhandle, 2012-13
Stanley Baldys, Monti M. Haynie, Amy M. Beussink
2014, Scientific Investigations Report 2014-5188

In cooperation with the North Plains Groundwater Conservation District (NPGCD), the U.S. Geological Survey collected and analyzed water-quality samples at 30 groundwater monitor wells in the NPGCD in the Texas Panhandle. All of the wells were completed in the Ogallala Formation of the central High Plains aquifer. Samples from each...

Water-level altitudes 2014 and water-level changes in the Chicot, Evangeline, and Jasper aquifers and compaction 1973-2013 in the Chicot and Evangeline aquifers, Houston-Galveston region, Texas
Mark C. Kasmarek, Michaela R. Johnson, Jason K. Ramage
2014, Scientific Investigations Map 3308

Most of the land-surface subsidence in the Houston-Galveston region, Texas, has occurred as a direct result of groundwater withdrawals for municipal supply, commercial and industrial use, and irrigation that depressured and dewatered the Chicot and Evangeline aquifers, thereby causing compaction of the aquifer sediments, mostly in the fine-grained clay and...

Simulation of groundwater flow in the Edwards-Trinity and related aquifers in the Pecos County region, Texas
Jonathan V. Thomas
2014, Fact Sheet 2014-3029

The Edwards-Trinity aquifer, a major aquifer in the Pecos County region of western Texas, is a vital groundwater resource for agricultural, industrial, and public supply uses. Resource managers would like to better understand the future availability of water in the Edwards-Trinity aquifer in the Pecos County region and the effects...

A multiphased approach to groundwater investigations for the Edwards-Trinity and related aquifers in the Pecos County region, Texas
Jonathan V. Thomas
2014, Fact Sheet 2014-3025

The Edwards-Trinity aquifer is a vital groundwater resource for agricultural, industrial, and public supply uses in the Pecos County region of western Texas. Resource managers would like to understand the future availability of water in the Edwards-Trinity aquifer in the Pecos County region and the effects of the possible increase...

Mesohabitats, fish assemblage composition, and mesohabitat use of the Rio Grande silvery minnow over a range of seasonal flow regimes in the Rio Grande/Rio Bravo del Norte, in and near Big Bend National Park, Texas, 2010-11
J. Bruce Moring, Christopher L. Braun, Daniel K. Pearson
2014, Scientific Investigations Report 2013-5210

In 2010–11, the U.S. Geological Survey (USGS), in cooperation with the U.S. Fish and Wildlife Service, evaluated the physical characteristics and fish assemblage composition of mapped river mesohabitats at four sites on the Rio Grande/Rio Bravo del Norte (hereinafter Rio Grande) in and near Big Bend National Park, Texas. The...

Geology and hydrostratigraphy of Guadalupe River State Park and Honey Creek State Natural Area, Kendall and Comal Counties, Texas
Allan K. Clark, Charles D. Blome, Robert R. Morris
2014, Scientific Investigations Map 3303

Hydrogeologic mapping and descriptions of the lithostratigraphy and hydrostratigraphy of Guadalupe River State Park and Honey Creek State Natural Area, Kendall and Comal Counties, Texas, are presented in this first detailed 1:24,000 geologic map, along with proposed names and descriptions of the hydrostratigraphic units in the study area. Variations in...

Hydrogeologic aspects of the Knippa Gap area in eastern Uvalde and western Medina counties, Texas
Rebecca B. Lambert, Allan K. Clark, Diana E. Pedraza, Robert R. Morris
2014, Fact Sheet 2014-3045

The Edwards aquifer is the primary source of potable water for the San Antonio area in south-central Texas. The Knippa Gap area is a structural low (trough) postulated to channel or restrict flow in the Edwards aquifer in eastern Uvalde and western Medina Counties, Tex. To better understand the function...

Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement
Barbara J. Mahler, Peter C. Van Metre, William T. Foreman
2014, Environmental Pollution (188) 81-87

Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected...

Factors affecting public-supply well vulnerability in two karst aquifers
MaryLynn Musgrove, Brian G. Katz, Lynne S. Fahlquist, Christy A. Crandall, Richard J. Lindgren
2014, Ground Water (52) 63-75

Karst aquifers occur in a range of climatic and geologic settings. Nonetheless, they are commonly characterized by their vulnerability to water-quality impairment. Two karst aquifers, the Edwards aquifer in south-central Texas and the Upper Floridan aquifer in western Florida, were investigated to assess factors that control the movement of contaminants...

Concentrations of selected constituents in surface-water and streambed-sediment samples collected from streams in and near an area of oil and natural-gas development, south-central Texas, 2011-13
Stephen P. Opsahl, Cassi L. Crow
2014, Data Series 836

During 2011–13, the U.S. Geological Survey, in cooperation with the San Antonio River Authority and the Guadalupe-Blanco River Authority, analyzed surface-water and streambed-sediment samples collected from 10 sites in the San Antonio River Basin to provide data for a broad range of constituents that might be associated with hydraulic fracturing...

Sediment characteristics in the San Antonio River Basin downstream from San Antonio, Texas, and at a site on the Guadalupe River downstream from the San Antonio River Basin, 1966-2013
Cassi L. Crow, J. Ryan Banta, Stephen P. Opsahl
2014, Scientific Investigations Report 2014-5048

San Antonio and surrounding municipalities in Bexar County, Texas, are in a rapidly urbanizing region in the San Antonio River Basin. The U.S. Geological Survey, in cooperation with the San Antonio River Authority and the Texas Water Development Board, compiled historical sediment data collected between 1996 and 2004 and collected...

Trend analysis and selected summary statistics of annual mean streamflow for 38 selected long-term U.S. Geological Survey streamgages in Texas, water years 1916-2012
William H. Asquith, Dana L. Barbie
2014, Scientific Investigations Report 2013-5230

In 2013, the U.S. Geological Survey (USGS) operated more than 500 continuous streamgages (streamflow-gaging stations) in Texas. In cooperation with the Texas Water Development Board, the USGS evaluated mean annual streamflow data for 38 selected streamgages that were active as of water year 2012. The 38 streamgages have annual mean...

Simulation of groundwater flow in the Edwards-Trinity and related aquifers in the Pecos County region, Texas
Brian R. Clark, Johnathan R. Bumgarner, Natalie A. Houston, Adam L. Foster
2014, Scientific Investigations Report 2013-5228

The Edwards-Trinity aquifer is a vital groundwater resource for agricultural, industrial, and public supply uses in the Pecos County region of western Texas. The U.S. Geological Survey completed a comprehensive, integrated analysis of available hydrogeologic data to develop a numerical groundwater-flow model of the Edwards-Trinity and related aquifers in the...

Quantifying the predictive consequences of model error with linear subspace analysis
Jeremy T. White, John E. Doherty, Joseph D. Hughes
2014, Water Resources Research (50) 1152-1173

All computer models are simplified and imperfect simulators of complex natural systems. The discrepancy arising from simplification induces bias in model predictions, which may be amplified by the process of model calibration. This paper presents a new method to identify and quantify the predictive consequences of calibrating a simplified computer...

Linkage of the Soil and Water Assessment Tool and the Texas Water Availability Model to simulate the effects of brush management on monthly storage of Canyon Lake, south-central Texas, 1995-2010
William H. Asquith, Johnathan R. Bumgarner
2014, Scientific Investigations Report 2013-5239

The U.S. Geological Survey (USGS), in cooperation with the Texas State Soil and Water Conservation Board, developed and applied an approach to create a linkage between the published upper Guadalupe River Soil Water Assessment Tool (SWAT) brush-management (ashe juniper [Juniperus ashei]) model and the full authorization version Guadalupe River Water...

Parameter estimation for the 4-parameter Asymmetric Exponential Power distribution by the method of L-moments using R
William H. Asquith
2014, Computational Statistics and Data Analysis (71) 955-970

The implementation characteristics of two method of L-moments (MLM) algorithms for parameter estimation of the 4-parameter Asymmetric Exponential Power (AEP4) distribution are studied using the R environment for statistical computing. The objective is to validate the algorithms for general application of the AEP4 using R. An algorithm was introduced in...

Response to comment on "Cancer risk from incidental ingestion exposures to PAHs associated with coal-tar-sealed pavement"
E. Spencer William, Barbara J. Mahler, Peter C. Van Metre
2014, Environmental Science and Technology (48) 870-871

No abstract available....

PAH concentrations in lake sediment decline following ban on coal-tar-based pavement sealants in Austin, Texas
Peter C. Van Metre, Barbara J. Mahler
2013, Environmental Science and Technology (48) 7222-7228

Recent studies have concluded that coal-tar-based pavement sealants are a major source of polycyclic aromatic hydrocarbons (PAHs) in urban settings in large parts of the United States. In 2006, Austin, TX, became the first jurisdiction in the U.S. to ban the use of coal-tar sealants. We evaluated the effect of...