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Articles 51841 - 51870 of 59402
Full-Text Articles in Entire DC Network
Subsurface Heavy-Metal Detection With The Use Of A Laser-Induced Breakdown Spectroscopy (Libs) Penetrometer System, Brian Miles, Javier Cortes
Subsurface Heavy-Metal Detection With The Use Of A Laser-Induced Breakdown Spectroscopy (Libs) Penetrometer System, Brian Miles, Javier Cortes
United States Army Corps of Engineers, Omaha District
U.S. Army Engineer Waterways Experiment Station (WES) investigators have designed, fabricated, and demonstrated a cone penetrometer sensor for subsurface in situ field screening based on LIBS. The LIBS probe (patent pending) presented here is one of a suite of contaminant and geophysical probes developed by the WES Site Characterization and Analysis Penetrometer System (SCAPS) program. The LIBS probe includes a laser as part of the optical LIBS sensor section for metals analysis and a cone and sleeve soil classification module at its tip. Soil classification data are acquired during the push, while LIBS data are recorded during probe retraction, after …
Estimates Of Annual Survival Probabilities For Adult Florida Manatees (Trichechus Manatus Latirostris), C. A. Langtimm, T. J. O'Shea, R. Pradel, C. A. Beck
Estimates Of Annual Survival Probabilities For Adult Florida Manatees (Trichechus Manatus Latirostris), C. A. Langtimm, T. J. O'Shea, R. Pradel, C. A. Beck
United States Geological Survey: Staff Publications
The population dynamics of large, long-lived mammals are particularly sensitive to changes in adult survival. Understanding factors affecting survival patterns is therefore critical for developing and testing theories of population dynamics and for developing management strategies aimed at preventing declines or extinction in such taxa. Few studies have used modern analytical approaches for analyzing variation and testing hypotheses about survival probabilities in large mammals. This paper reports a detailed analysis of annual adult survival in the Florida manatee (Trichechus manatus latirostris), an endangered marine mammal, based on a mark-recapture approach. Natural and boat- inflicted scars distinctively "marked" individual …
Determination Of Bioavailable Contaminants In The Lower Missouri River Following The Flood Of 1993, Jimmie Petty, Barry Poulton, Colette Charbonneau, James Huckins, Susan Jones, Jennifer Cameron, Harry Prest
Determination Of Bioavailable Contaminants In The Lower Missouri River Following The Flood Of 1993, Jimmie Petty, Barry Poulton, Colette Charbonneau, James Huckins, Susan Jones, Jennifer Cameron, Harry Prest
United States Geological Survey: Staff Publications
The semipermeable membrane device (SPMD) technology was employed to determine the presence of bioavailable organochlorine pesticides (OCs), polychlorinated biphenyls (PCBs), and polyaromatic hydrocarbons (PAHs) in the water of the main stem of the lower Missouri River and three of its tributaries. The SPMDs were deployed in 1994 following the extensive flood of 1993. Specifically, the SPMDs were deployed for 28 days at Wilson State Park, IA; Nebraska City, NE; Parkville, MO; the Kansas River in Kansas City, KS; Napoleon, MO; the Grand River; Glasgow, MO; the Missouri River upstream from the confluence of the Gasconade River; the Gasconade River; and …
Occurrence Of Pesticides In Shallow Groundwater Of The United States: Initial Results From The National Water-Quality Assessment Program, Dana Kolpin, Jake Barbash, Robert Gilliom
Occurrence Of Pesticides In Shallow Groundwater Of The United States: Initial Results From The National Water-Quality Assessment Program, Dana Kolpin, Jake Barbash, Robert Gilliom
United States Geological Survey: Staff Publications
The first phase of intensive data collection for the National Water-Quality Assessment (NAWQA) was completed during 1993-1995 in 20 major hydrologic basins of the United States. Groundwater land-use studies, designed to sample recently recharged groundwater (generally within 10 years) beneath specific land-use and hydrogeologic settings, are a major component of the groundwater quality assessment for NAWQA. Pesticide results from the 41 land use studies conducted during 1993-1995 indicate that pesticides were commonly detected in shallow groundwater, having been found at 54.4% of the 1034 sites sampled in agricultural and urban settings across the United States. Pesticide concentrations were generally low, …
9. Alteration Of Uppermost Lavas And Volcaniclastics Recovered During Leg 152 To The East Greenland Margin, Mary Anne Holmes
9. Alteration Of Uppermost Lavas And Volcaniclastics Recovered During Leg 152 To The East Greenland Margin, Mary Anne Holmes
Department of Earth and Atmospheric Sciences: Faculty Publications
During the last stages of the eruption of syn-rift basalts along the East Greenland Margin, debris flows and/or pyroclastic deposits were emplaced at Ocean Drilling Program Sites 915 and 916. The deposits and the tops of the lava flows at Site 918 were altered by subaerial weathering processes as indicated by downhole changes in mineral and chemical composition, and by the mineral paragenesis. Kaolinite and goethite, which form in acidic waters, are abundant at the tops of the weathering profiles and decrease in abundance downward. They are replaced by a smectite-hematite-opal assemblage at the bases of the weathered profiles. Gibbsite …
Book Review Of Paleolimnology Of Europeanmaar Lakes By J. F.W. Negendank & B. Zolitschka (Eds)., J. Platt Bradbury
Book Review Of Paleolimnology Of Europeanmaar Lakes By J. F.W. Negendank & B. Zolitschka (Eds)., J. Platt Bradbury
United States Geological Survey: Staff Publications
This book represents a collection of papers presented at a symposium in May, 1991 on the formation and paleolimnology of European maar lakes. Paleolimnological discussions embrace maar lake deposits of late Quaternary to early Tertiary age in Germany, France and Italy. The goal of the symposium and its outgrowth, this book, is to develop a funding initiative to study, core and analyze the deposits of these remarkable depositional systems.
Observation Of The Seismic Nucleation Phase In The Ridgecrest, California, Earthquake Sequence, William L. Ellsworth, Gregory C. Beroza
Observation Of The Seismic Nucleation Phase In The Ridgecrest, California, Earthquake Sequence, William L. Ellsworth, Gregory C. Beroza
United States Geological Survey: Staff Publications
Near-source observations of five M 3.8-5.2 earthquakes near Ridgecrest, California are consistent with the presence of a seismic nucleation phase. These earthquakes start abruptly, but then slow or stop before rapidly growing again toward their maximum rate of moment release. Deconvolution of instrument and path effects by empirical Green's functions demonstrates that the initial complexity at the start of the earthquake is a source effect. The rapid growth of the P-wave arrival at the start of the seismic nucleation phase supports the conclusion of Mori and Kanamori [1996] that these earthquakes begin without a magnitude-scaled slow initial phase of the …
Seismic Rock-Physics Model For Carbonates At Low Effective Stress Levels
Seismic Rock-Physics Model For Carbonates At Low Effective Stress Levels
United States Geological Survey: Staff Publications
When considering the seismic response from the Dammam aquifer, the first required component is a simple model relating porosity and stress state to frame moduli assuming a carbonate matrix. We explored two such relationships, one based on the empirical regression presented by Domenico (1984) and a second using the critical porosity model of Nur et al. (1998) calibrated to the ultrasonic measurements of Nur and Simmons (1969). Once frame properties for a given porosity/pressure state were estimated, the effect of fluid changes were calculated using the low-frequency form of the Biot-Gassmann model, better known as Gassmann fluid substitution (Mavko …
Continuous Lake-Sediment Records Of Glaciation In The Sierra Nevada Between 52,600 And 12,500 14c Yr B.P., Larry Benson, Howard M. May, Ronald C. Antweiler, Terry I. Brinton, Michaele Kashgarian, Joseph P. Smoot, Steve P. Lund
Continuous Lake-Sediment Records Of Glaciation In The Sierra Nevada Between 52,600 And 12,500 14c Yr B.P., Larry Benson, Howard M. May, Ronald C. Antweiler, Terry I. Brinton, Michaele Kashgarian, Joseph P. Smoot, Steve P. Lund
United States Geological Survey: Staff Publications
The chemistry of the carbonate-free clay-size fraction of Owens Lake sediments supports the use of total organic carbon and magnetic susceptibility as indicators of stadial-interstadial oscillations, Owens Lake records of total organic carbon, magnetic susceptibility, and chemical composition of the carbonate-free, clay-size fraction indicate that Tioga glaciation began ~24,500 and ended by ~13,600 14C yr B.P. Many of the components of glacial rock flour (e.g., TiO2 , MnO, BaO) found in Owens Lake sediments achieved maximum values during the Tioga glaciation when valley glaciers reached their greatest extent. Total organic carbon and Si02 (amorphous) concentrations reached minimum values …
Early Life History Stages Of Gulf Sturgeon In The Suwannee River, Florida, Kenneth J. Sulak, James P. Clugston
Early Life History Stages Of Gulf Sturgeon In The Suwannee River, Florida, Kenneth J. Sulak, James P. Clugston
United States Geological Survey: Staff Publications
Egg sampling confirmed that Suwannee River Gulf sturgeon Acipenser ozyrinchus desotoi, a subspecies of Atlantic sturgeon A. o. oxyrinchus use the same spawning site at river kilometer (rkm) 215 from the mouth of the river each year. Forty-nine eggs were recorded in 1995, and 368 were recorded in 1996. Spawning began 4-7 d after the March new moon in both years and lasted 10-11 d; in 1996, a second 10-d spawning round began on the April new moon. Developmental synchrony among eggs recovered suggested serval discrete spawning events in both years. Total eggs deposited for three 1996 sampling days …
Filtration Modeling Of A Plate-And-Frame Press, Scott A. Wells
Filtration Modeling Of A Plate-And-Frame Press, Scott A. Wells
Civil and Environmental Engineering Faculty Publications and Presentations
The porosity distribution and filtrate production during cake filtration in a plate-and-frame filter press were simulated mathematically. The model considered filtration that occurs after the filling process, not filtration that occurs as the suspension fills the cell. Governing equations for the temporal porosity distribution were developed for a plateand- frame press. The governing equations were solved numerically using an alternating-direction-implicit scheme. Appropriate initial and boundary conditions were determined based on characteristics of the plate-and-frame press and of the suspension properties. Predicted porosity and velocity distributions were calculated for assumed constitutive parameters.
Modeling Density Currents In Circular Clarifiers, Scott A. Wells, David M. Laliberte
Modeling Density Currents In Circular Clarifiers, Scott A. Wells, David M. Laliberte
Civil and Environmental Engineering Faculty Publications and Presentations
Design of sedimentation tanks for solid-liquid separation is often dependent on assuming ideal flow conditions. But the geometry of the tank and density currents as a result of temperature and suspended solids influences the fluid mechanics of the tank and can result in significant deviations from ideal flow.
A two-dimensional radial flow model was proposed which incorporated the effect of density currents resulting from temperature and suspended solids differentials within the tank. The numerical model predicted the steady-state, layer-averaged radial flow and layer depth.
The model solution and field data showed that the momentum and suspended solids of the inflow …
Gravity Drainage Prior To Cake Filtration, Scott A. Wells, Gregory K. Savage
Gravity Drainage Prior To Cake Filtration, Scott A. Wells, Gregory K. Savage
Civil and Environmental Engineering Faculty Publications and Presentations
During the initial stages of a Buchner funnel or specific resistance test, gravity drainage occurs prior to application of the pressure differential. Some allow time for a small cake to form by gravity drainage. Filtrate data from the gravity drainage period can be used to determine constitutive properties of the cake under a hydrostatic pressure gradient. The constitutive properties that define the structure of the cake include the permeability and porosity as functions of the applied stress. Equations governing the drainage rate during a gravity filtration experiment assuming a constant and a non-constant average cake permeability and cake porosity were …
Determining Capture Zones For Three-Dimensional, Heterogeneous, Anisotropic Aquifers By Monte Carlo Analysis, Jon Paul Jones
Determining Capture Zones For Three-Dimensional, Heterogeneous, Anisotropic Aquifers By Monte Carlo Analysis, Jon Paul Jones
Theses and Dissertations
Most methods of delineating capture zones for pump-and-treat remedial design and wellhead protection assume a two-dimensional, homogeneous aquifer. Aquifers, however, are three-dimensional and heterogeneous, thereby introducing uncertainty in capture zone analysis. This study used a Monte Carlo analysis of three sets of statistical parameters defining aquifer heterogeneity. Each set had a different variance for the mean natural log hydraulic conductivity, which varied among the sets by a factor of four. The ensemble means of the capture zones for each set were estimated from 10 randomly generated fields with 12 layers each which were superimposed on each other for a total …
The Biogeochemical Cycling Of Dissolved Organic Nitrogen In Estuarine Sediments, David J. Burdige, Shilong Zheng
The Biogeochemical Cycling Of Dissolved Organic Nitrogen In Estuarine Sediments, David J. Burdige, Shilong Zheng
OES Faculty Publications
Benthic fluxes and pore-water profiles of dissolved organic nitrogen and carbon (DON and DOC, respectively) were determined in seasonal studies at contrasting sites in Chesapeake Bay. Pore-water dissolved organic matter (DOM) concentrations were elevated over bottom-water values, generally increased with depth, and ranged from 15 to similar to 160 μM for DON and ~200-2000 μM for DOC. Pore-water DOM concentrations and the C:N ratio of this material showed spatial (depth) and temporal changes that varied among the sites studied. These trends appeared to be related to differences in the types of sediment organic matter (SOM) undergoing remineralization, as well as …
Iron In Ice Cores From Law Dome, East Antarctica: Implications For Past Deposition Of Aerosol Iron, R. Edwards, Peter N. Sedwick, Vin Morgan, C. F. Boutron, S. Hong
Iron In Ice Cores From Law Dome, East Antarctica: Implications For Past Deposition Of Aerosol Iron, R. Edwards, Peter N. Sedwick, Vin Morgan, C. F. Boutron, S. Hong
OES Faculty Publications
Total-dissolvable iron has been measured in sections of three ice cores from Law Dome, East Antarctica, and the results used to calculate atmospheric iron deposition over this region during the late Holocene and to provide a preliminary est. of aerosol iron deposition during the Last Glacial Maximum (LGM). Ice-core sections dating from 56-2730 BP (late Holocene) and ∼18 000 BP (LGM) were decontaminated using trace-metal clean techniques, and total-dissolvable iron was determined in the acidified meltwaters by flow-injection analysis. Our results suggest that the atmospheric iron flux onto the Law Dome region has varied significantly over time-scales ranging from seasonal …
Lead Isotopes And Selected Metals In Ice From Law Dome, Antarctica, K. J. R. Rosman, W. Chisholm, C. F. Boutron, S. Hong, R. Edwards, Vin Morgan, Peter N. Sedwick
Lead Isotopes And Selected Metals In Ice From Law Dome, Antarctica, K. J. R. Rosman, W. Chisholm, C. F. Boutron, S. Hong, R. Edwards, Vin Morgan, Peter N. Sedwick
OES Faculty Publications
The isotopic composition. of Pb and the concentrations of Pb, Ba and Bi were measured in selected ice-core samples from Law Dome, East Antarctica, to a depth of 1196 m. The range of concentrations found in decontaminated ice was 0.03-1.5 pg g-1 for Pb, 0.9-6.1 pg g-1 for Ba and 0.4-17 fg g-1 for Bi, excluding the deepest sample which contained ∼1 ppm of rock dust. The abundances of all four stable lead isotopes were measured and gave 206Pb/207Pb ratios ≤ ∼1.23. A value of 208Pb/207Pb = 2.78 was measured in …
On The Strain-Rate Sensitivity Of Columnar Ice, M. E. Manley, E. M. Schulson
On The Strain-Rate Sensitivity Of Columnar Ice, M. E. Manley, E. M. Schulson
Dartmouth Scholarship
A power law relation between stress and strain rate of the form σ ∝ ε̇1/n was used to describe the response to strain rate of S1 ice loaded across the columns at -10°C. The rate exponent, n, decreased with increasing strain from about 4.6 at an observed peak on the load displacement curve to approximately 2.6 at a shortening of 2%. Analysis of these results and of the results of other authors on different forms of ice deformed at the same temperature suggests that the power law exponent, n, is proportional to Fc/Fg. The parameter Fc/Fg is the far-field basal …
A Palynological Study Of Two Upland Bogs In The Gulf Coastal Plain, Alabama And Mississippi, Linda C. Pace
A Palynological Study Of Two Upland Bogs In The Gulf Coastal Plain, Alabama And Mississippi, Linda C. Pace
LSU Historical Dissertations and Theses
Fewer Quaternary palynological studies have been conducted in the Gulf Coastal Plain of the southeastern United States than In the northern United States and Canada, resulting in major gaps in the pollen record of this region. The existing studies display discrepancies in the chronology of the pine rise, appearance of the modem climatic regime and vegetation, and timing of the Hypsithermal. In order to fill a gap in the paleoecological data network of the Gulf Coastal Plain, pollen analysis, charcoal analysis, and sediment stratigraphic techniques were used to reconstruct the last 6500 years of Sweetbay Bog, Mississippi, and Minamac Bog, …
Effective Elastic Thickness Of The Lithosphere Along The Easter Seamount Chain, Sarah E. Kruse, Zhengro J. Liu, David F. Naar, Robert A. Duncan
Effective Elastic Thickness Of The Lithosphere Along The Easter Seamount Chain, Sarah E. Kruse, Zhengro J. Liu, David F. Naar, Robert A. Duncan
Geology Faculty Publications
Bathymetry and gravity data collected during Legs 5, 6, and 7 of the 1993 GLORIA Expedition and the recently released 2-min altimetry-derived global gravity grid are used to determine the effective elastic thickness of the lithosphere along the Easter Seamount Chain (ESC). Forward modeling, admittance, and coherence methods yield consistent results. With the exception of the eastern and western ends of the ESC the effective elastic thickness along the chain is ∼1–4 km. The thin elastic thickness for the majority of the ESC seamounts is compatible with a young seafloor age at the time of loading derived from new radiometric …
Forensic Soil Analysis: Characterization Of The Sand Fraction, John Baize
Forensic Soil Analysis: Characterization Of The Sand Fraction, John Baize
Masters Theses & Specialist Projects
The purpose of this project was to develop a comprehensive analytical method for the characterization of soil by examining particle size, elemental composition, and percent organic matter in soil, and to determine its forensic applicability. In this study, five soils of varying geological locations were examined including two samples from Kentucky; two samples from Pennsylvania; and one from Washington D C A Gilson sonic sieve shaker was used to separate fractions of soil to determine particle size, and a JEOL scanning electron microscope with a Kevex EDS detector was used to determine elemental composition. These techniques coupled with percent total …
Mathematical Modeling Of Convective Heat Transfer In Mammoth Cave, Jonathan Jernigan
Mathematical Modeling Of Convective Heat Transfer In Mammoth Cave, Jonathan Jernigan
Masters Theses & Specialist Projects
Around two centuries ago, changes were made to the entrances of Mammoth Cave and its passages. Today the Historic Entrance to Mammoth Cave is enlarged and the passage just beyond the entrance known as Houchins' Narrows has been cleared of rubble and filled with sediments. These enlargements have resulted in an increase in airflow throughout the Historic Section of the cave causing environmental conditions such as air temperature and airflow to fluctuate. These fluctuations have negatively impacted inhabitants and contents of the cave system. To restore natural conditions within the cave, Science and Resource Management personnel at Mammoth Cave National …
Development Of An Atmospheric Fluidized Bed Combustor (Afbc), William Orndorff
Development Of An Atmospheric Fluidized Bed Combustor (Afbc), William Orndorff
Masters Theses & Specialist Projects
The relatively recent interest in the U.S. in the development of atmospheric fluidized bed combustion (AFBC) has been preceded by two main factors. First of these is the ever present problem of acid rain and growing public support for cleaner burning fossil fuels. Second is the increasing demand on public landfills and subsequent need for burning of municipal solid waste. From these factors and their corresponding influences, Western Kentucky University has the impetus and has received the financial assistance necessary to build and develop a laboratory scale AFBC system. A brief history of the events leading to this development, as …
Volcanology And Geochemistry Of Pliocene And Quaternary Basalts On Citadel Mountain, Lunar Crater Volcanic Field, Pancake Range, Nevada, Loretta D. Dickson
Volcanology And Geochemistry Of Pliocene And Quaternary Basalts On Citadel Mountain, Lunar Crater Volcanic Field, Pancake Range, Nevada, Loretta D. Dickson
UNLV Theses, Dissertations, Professional Papers, and Capstones
Alkali basalts on Citadel Mountain form the southern margin of the Lunar Crater Volcanic Field (LCVF) in the central Great Basin, Nevada. Citadel Mountain comprised of a faulted, north tilted section of Tertiary andesite and ash-flow tuff is capped by Pliocene and Quaternary alkali basalt flows that erupted from six major cinder cones. The basalt flows on Citadel Mountain can be divided into two groups (older and younger) based on age and isotopic signatures. The older basalt group is characterized by higher 87 Sr/86Sr and lower ENd and the younger group has lower 87Sr/86Sr …
Vertical Axis Rotation In The Silurian Hills: A Cenozoic Overprint On The Mesozoic U.S. Cordilleran Magmatic Arc, John E. Comstock
Vertical Axis Rotation In The Silurian Hills: A Cenozoic Overprint On The Mesozoic U.S. Cordilleran Magmatic Arc, John E. Comstock
LSU New Orleans Theses and Dissertations
New, detailed field work in the Silurian hills, southeast of Death Valley, reveals a pattern of a complex Cenozoic brittle fault overprint of rocks containing evidence of at least three episodes of Mesozoic thermal-ductile deformation. The Cenozoic brittle fault overprint of rocks containing evidence of at least three episodes of Mesozoic thermal-ductile formation. The Cenozoic faulting consists of five distinct sets of structures ordered by cross cutting relationships. The oldest, BF1, are fragments of reverse faults trending NW and dipping 45-60 SW. BF2 consist of NW trending, en echelon, sinistral strike-slip faults. BF3 is a conjugate set of N-NE trending …
Laboratory Comparison Of Trench Design Options For Recovering Spilled Oil, Renuka Fernando
Laboratory Comparison Of Trench Design Options For Recovering Spilled Oil, Renuka Fernando
Masters Theses
The research goal was to improve the performance of drainage trenches used to recover spilled oil in the subsurface. Different trench designs were compared in two laboratory experiments. The first laboratory experiment clearly demonstrates that the performance of a oil recovering drainage trench could be improved by replacing the standard gravel pack sand used around the drain pipe with mixtures of teflon and sand. The effectiveness of a downgradient impermeable 'backstop' also was studied in the first experiment.
In experiment two, four trench designs were compared: perforated drain pipe; wire-wrapped horizontal well screen; perforated sheet pile; and gravel fill with …
A Comparison Study Of Water Well Grouting Materials, Sherry L. Callaway
A Comparison Study Of Water Well Grouting Materials, Sherry L. Callaway
Masters Theses
To prevent contamination from occurring in water wells, and thereby groundwater, the annulus between the well casing and borehole wall must be sealed with a grout that is capable of maintaining a proper seal. Several factors and properties determine the integrity of the grout and the seal formed by that grout.
A field study discovered limitations in all of the tested grout types. Most grouts were found to vary greatly in thickness surrounding the well casing. Bentonite slurry grouts settled excessively. Cement and bentoni tecement grouts did not adhere to PVC well casing. Bentonite-cement grout fractured. The granulated bentonite was …
Lithologic And Stratigraphic Analysis Of Glacial Diamictons, Sturgis, Michigan, R. Christopher Gardner
Lithologic And Stratigraphic Analysis Of Glacial Diamictons, Sturgis, Michigan, R. Christopher Gardner
Masters Theses
Seven diamictons are identified in the subsurface glacial drift near Sturgis, Michigan using textural analyses and x-ray diffraction of clay minerals. The clay mineral content is quantified by comparing the 7-A/10- A peak height ratios from x-ray diffraction diffractograms of oriented clay-size particle (< 2um) mounts. Two diamictons occur at the base of the drift. Unit 1 is gray , resembling the shale it overlies. The texture of Unit 1 is sandy clay loam to loam and average 7-A/10-A peak height clay mineral ratios of 0.446 ±0.069. Unit 2 is a yellowish-brown diamicton, it overlies Unit 1, and is a sandy loam to loam with average 7-A/10-A clay mineral ratio of 0.657 ±0.151. Diamicton Units 4 and 5 overlie a thick unit of sand and gravel on top of Unit 2. Units 4 and 5 have similar color and texture, however the 7-A/10-A ratios are 1.059 ±0.090 and 0.810 ±0.072 respectively. Unit 6 is a thin diamicton unit, leached of calcite, and x-ray diffraction suggests that there is a range of weathering horzins between borings. Unit 7 is loamy, whereas Unit 8 generally ranges from sandy clay loam to sandy loam with average 7-A/10-A ratios of 0.865 ±0.090 and 1.195 ±0.189.
The Migration Of Arsenic And Lead In Surface Sediments At Three Kids Mine Henderson, Nevada, Douglas Brian Sims
The Migration Of Arsenic And Lead In Surface Sediments At Three Kids Mine Henderson, Nevada, Douglas Brian Sims
Publications (WR)
This study focused on the distribution of arsenic and lead in surface sediments at Three Kids Mine in Henderson, Nevada. The mine site encompasses approximately 470 acres of desert and is situated above two developing communities (Lake Las Vegas and Calico Ridge) and the Las Vegas Valley's water source (Lake Mead). Transport of arsenic and lead appears to have occurred within a limited range in both the eastern and western washes on the eastern and western sides of Three Kids Mine. Concentrations of arsenic range between 20 mg/kg (ppm) and 1130 mg/kg and between 20 mg/kg and 8400 mg/kg for …
Strawberry Valley Assessment, A Cooperative Project Between The Mitigation Commission & The U.S. Forest Service, Mitigation Commission, U.S. Forest Service
Strawberry Valley Assessment, A Cooperative Project Between The Mitigation Commission & The U.S. Forest Service, Mitigation Commission, U.S. Forest Service
All U.S. Government Documents (Utah Regional Depository)
No abstract provided.