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Water Resources And Geologic Field Trip In York And Seward Counties, Nebraska, Michael J. Jess, Mark Burbach Nov 2006

Water Resources And Geologic Field Trip In York And Seward Counties, Nebraska, Michael J. Jess, Mark Burbach

Conservation and Survey Division

No abstract provided.


Occurrence Of Sulfonamide Antimicrobials In Private Water Wells In Washington County, Idaho, Usa, Angela L. Batt, Daniel D. Snow, Diana S. Aga Sep 2006

Occurrence Of Sulfonamide Antimicrobials In Private Water Wells In Washington County, Idaho, Usa, Angela L. Batt, Daniel D. Snow, Diana S. Aga

Nebraska Water Center: Faculty Publications

County (Weiser, Idaho) were collected to assess the impact of a nearby confined animal feeding operation (CAFO) on the quality of the local groundwater. All six samples were found contaminated by two veterinary antimicrobials, sulfamethazine (at concentrations from 0.076 to 0.22 μg/l) and sulfadimethoxine (at concentrations from 0.046 to 0.068 μg/l). These groundwater samples also contained elevated concentrations of nitrate and ammonium. Three of the sampled wells have nitrate levels that exceeded the maximum contaminant level set by the US Environmental Protection Agency for drinking water, with nitrate concentration as high as 39.1 mg/l. All but one well showed nitrate, …


Lockhart Catchment Appraisal 2005, Susan Murphy-White, P Leoni Jun 2006

Lockhart Catchment Appraisal 2005, Susan Murphy-White, P Leoni

Resource management technical reports

The Lockhart Catchment is the largest subcatchment of the Avon River Basin covering just over 3.56 million hectares, including 15 Shires running from Quairading and Bruce Rock in the north to Pingrup and Lake King in the south. This document aims to give the reader a starting point from which to further assess larger scale areas of the catchment for the purpose of planning to reverse and improve land degradation and sustainable farming in Western Australia.


Ground-Penetrating Radar Theory And Application Of Thin-Bed Offset-Dependent Reflectivity, John H. Bradford, Jacob C. Deeds May 2006

Ground-Penetrating Radar Theory And Application Of Thin-Bed Offset-Dependent Reflectivity, John H. Bradford, Jacob C. Deeds

CGISS Publications and Presentations

Offset-dependent reflectivity or amplitude-variationwith- offset (AVO) analysis of ground-penetrating radar (GPR) data may improve the resolution of subsurface dielectric permittivity estimates. A horizontally stratified medium has a limiting layer thickness below which thin-bed AVO analysis is necessary. For a typical GPR signal, this limit is approximately 0.75 of the characteristic wavelength of the signal. Our approach to modeling the GPR thin-bed response is a broadband, frequency-dependent computation that utilizes an analytical solution to the three-interface reflectivity and is easy to implement for either transverse electric (TE) or transverse magnetic (TM) polarizations. The AVO curves for TE and TM modes differ …


Reflectivity Modeling Of A Ground-Penetrating-Radar Profile Of A Saturated Fluvial Formation, William P. Clement, Warren Barrash, Michael D. Knoll May 2006

Reflectivity Modeling Of A Ground-Penetrating-Radar Profile Of A Saturated Fluvial Formation, William P. Clement, Warren Barrash, Michael D. Knoll

Geosciences Faculty Publications and Presentations

Major horizons in radar reflection profiles may correlate with contacts between stratigraphic units or with structural breaks such as fault surfaces. Minor reflections may be caused by clutter or, in some cases, may indicate material properties or structure within stratigraphic units. In this study, we examine the physical basis for major and minor reflections observed in a shallow, unconfined, fluvial aquifer near Boise, Idaho, U. S. A. We compare a 2D profile from a surface ground-penetrating-radar reflection transect with the 1D modeled reflection profiles at three wells adjacent to the surface-reflection profile. The 1D models are based on dielectric constant …


Investigating The Stratigraphy Of An Alluvial Aquifer Using Crosswell Seismic Traveltime Tomography, Geoff J.M. Moret, Michael D. Knoll, Warren Barrash, William P. Clement May 2006

Investigating The Stratigraphy Of An Alluvial Aquifer Using Crosswell Seismic Traveltime Tomography, Geoff J.M. Moret, Michael D. Knoll, Warren Barrash, William P. Clement

CGISS Publications and Presentations

In this study, we investigate the use of crosswell P-wave seismic tomography to obtain spatially extensive information about subsurface sedimentary architecture and heterogeneity in alluvial aquifers. Our field site was a research wellfield in an unconfined aquifer near Boise, Idaho. The aquifer consists of a ~ 20-m-thick sequence of alluvial cobble- and-sand deposits, which have been subdivided into five stratigraphic units based on neutron porosity logs, grainsize analysis, and radar reflection data. We collected crosswell and borehole-to-surface seismic data in wells 17.1 m apart. We carefully considered the impact of well deviation, data quality control, and the choice of inversion …


Geostatistical And Stochastic Study Of Radio Nuclide Transport In The Unsaturated Zone At Yucca Mountain, Ming Ye, Amy J. Smiecinski, Raymond E. Keeler May 2006

Geostatistical And Stochastic Study Of Radio Nuclide Transport In The Unsaturated Zone At Yucca Mountain, Ming Ye, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

The U.S. Nuclear Waste Technical Review Board [Cohon et al. 1998] evaluated the technical and scientific validity of activities undertaken by the Secretary of Energy to characterize Yucca Mountain, Nevada, for its suitability as an underground repository in which to store high-level radioactive waste and spent nuclear fuel. In the report, the Board pinpointed that the study on groundwater flow and radionuclide transport in the saturated and unsaturated zones below Yucca Mountain should, over the next several years, focus on reducing prediction uncertainty. In its 2002, the Board repeated this concern by stating, “… hydrogeologic processes that affect radionuclide transport …


Traveltime Inversion Of Vertical Radar Profiles, William P. Clement, Michael D. Knoll May 2006

Traveltime Inversion Of Vertical Radar Profiles, William P. Clement, Michael D. Knoll

Geosciences Faculty Publications and Presentations

Traveltimes of direct arrivals in vertical radar profiles (VRPs) are tomographically inverted to estimate the earth’s electromagnetic (EM) velocity between a surface transmitter and a downhole receiver. We determine the 1D interval velocity model that best fits the first-arrival traveltimes by using a weighted, damped, least-squares inversion scheme. We assess the accuracy of the velocity model using synthetic traveltimes from a known velocity-distribution model simulating an unconfined aquifer. The inverted velocity profile closely matched the velocity profile of the input model in the synthetic examples. Using vertical radar profile data from an unconfined aquifer near Boise, Idaho, we inverted traveltimes …


Generalized Geologic Map For Land-Use Planning: Carter County, Kentucky, Gerald A. Weisenfluh, Daniel I. Carey Jan 2006

Generalized Geologic Map For Land-Use Planning: Carter County, Kentucky, Gerald A. Weisenfluh, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Marion County, Kentucky, Daniel I. Carey, Garland R. Dever Jr., Adam Pike Jan 2006

Generalized Geologic Map For Land-Use Planning: Marion County, Kentucky, Daniel I. Carey, Garland R. Dever Jr., Adam Pike

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Groundwater Quality In Kentucky: Barium, Bart Davidson, R. Stephen Fisher Jan 2006

Groundwater Quality In Kentucky: Barium, Bart Davidson, R. Stephen Fisher

Information Circular--KGS

Barium is a silver-white alkaline earth metal that is not found free in nature because it is highly reactive with sulfate and carbonate. Barium compounds can be naturally occurring or man-made. The most common natural occurrence of barium is in the mineral barite (barium sulfate), which has many uses in industry, such as a filler in the making of rubber, plastic and resin, white pigment, drilling lubricants used in the oil and gas industry, paint, bricks and glass (Agency for Toxic Substances and Disease Registry, 2004). Barium sulfate is very slightly soluble in water and absorbs X-rays, making it an …


Generalized Geologic Map For Land-Use Planning: Mccreary County, Kentucky, Daniel I. Carey, Randall L. Paylor, Bethany L. Overfield Jan 2006

Generalized Geologic Map For Land-Use Planning: Mccreary County, Kentucky, Daniel I. Carey, Randall L. Paylor, Bethany L. Overfield

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Mason County, Kentucky, Daniel I. Carey Jan 2006

Generalized Geologic Map For Land-Use Planning: Mason County, Kentucky, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Whitley County, Kentucky, Daniel I. Carey, Bethany L. Overfield, Randall L. Paylor Jan 2006

Generalized Geologic Map For Land-Use Planning: Whitley County, Kentucky, Daniel I. Carey, Bethany L. Overfield, Randall L. Paylor

Map and Chart--KGS

No abstract provided.


Groundwater-Level Changes In Nebraska, Spring 2000 To Spring 2006/ Density Of Registered Irrigation Wells In Nebraska August 2005, Conservation Survey Division Jan 2006

Groundwater-Level Changes In Nebraska, Spring 2000 To Spring 2006/ Density Of Registered Irrigation Wells In Nebraska August 2005, Conservation Survey Division

Conservation and Survey Division

No abstract provided.


Ravensthorpe Area Catchment Appraisal 2006, A Massenbauer Jan 2006

Ravensthorpe Area Catchment Appraisal 2006, A Massenbauer

Resource management technical reports

The Ravensthorpe area covers 861, 000 hectares. Ninety percent of the study area covered in this report falls within the Ravensthorpe Shire, Western Australia. This document aims to give the reader a starting point from which to further assess larger scale areas of the catchment for the purpose of planning to reverse and improve land degradation and sustainable farming in Western Australia.