Erosion Potential of Pacific Basin Precipitation
Average annual erosivity (EI) values were developed using 20 years of hourly precipitation data from weather stations located on each of 10 Pacific Basin islands. Average annual erosivity...
Numerical Methods for Simulating Debris Blockage Failures and Mudflows
This paper presents the procedures and results from an investigation to evaluate the hydraulic characteristics of mudflow events resulting from hypothetical failures of a debris blockage...
Modeling Nitrogen Movement Through Loess Soils
This study evaluates the ability of the Root Zone Water Quality Model (RZWQM) to track the movement and fate of nitrate (NO3--N)...
Two-Dimensional Analysis of Furrow Infiltration
A general applicable two-dimensional unsaturated-saturated model for transient soil-water flow conditions in heteogeneous soils was developed. The water flow model was applied to simulate...
Heavy Metal Transport in the Columbia River, British Columbia
Data on the total forms of selected metals were used to assess their concentrations at two sampling sites on the Canadian Columbia River from 1984 to 1989. Cadmium, the response variable...
Common Mistakes in Model Applications
To apply models to groundwater problems, the hydrologist generally uses the following three-phased approach: (1) system conceptualization, (2) history matching (or model calibration),...
Sensitivity Analysis of a Ground-Water-Flow Model
A sensitivity analysis was performed on 18 hydrological factors affecting steady-state groundwater flow in the Upper Floridan aquifer near Albany, southwestern Georgia. Computations were...
An Overview of EPRI Hydrogeochemical Code FASTCHEMTM
The capabilities of the flow and transport modules that make up FASTCHEM are described. The linkages among the various modules that are required to achieve a hydrogeochemical analysis...
Measurement and Analysis of Hydraulic Conductivity Variability of a Heterogeneous Aquifer
The spatial variability of hydraulic conductivity of a shallow alluvial aquifer was investigated using borehole flowmeter measurements. The study was conducted at the site of a large-scale...
Slug Test: Double-Porosity, Linear Boundary, and Variable Storage Effects
The intention of this paper is to focus on three aspects of the slug test that are not as familiar as the main analysis techniques: the effects of double-porosity formations, the effects...
Prematurely Terminated Slug Tests?A Field Application
Slug tests suffer problems of non-uniqueness to a greater extent than other well tests. Alternatively, a prematurely terminated slug test (PTST) or a systematized drillstem test is proposed,...
A Preliminary Evaluation of Model Uncertainty Given Parameter Sensitivity for Select Transport Codes
The ever-increasing use of mathematical models in groundwater management has raised concerns as to uncertainties associated with their abilities to simulate real-world pollution problems....
Groundwater Modeling with GIS: An Example
The versatility and widespread usage of a geographic information system (GIS) as a hydrological modeling tool is only now showing up in the literature. In this regard, a research team...
On the Application of Multiphase Flow Models for the Simulation of Density Stratified Flow in Aquifers
Two types of numerical simulation approach are usually applied when simulating density-stratified flow in aquifers: (a) the sharp interface approach, and (b) the coupling of flow transport...
Evaluation of Embankment Erosion at TVA's Chickamauga Project
Studies were made to evaluate the extent of erosion to be expected under probable maximum flood (PMF) conditions. The erosion studies were made using the EMBANK computer program. The results...
Hydraulic Features of Flexible Curtains Used for Selective Withdrawal
Flexible curtain barriers are being investigated as a way to modify power penstock intakes to achieve selective withdrawal. The curtain barrier controls the elevation from which water...
Modeling and Field Experiments for Tracer Gas Tests
Numerical modeling and field experiments were used to extend the tracer gas technique for determining surface gas transfer rates to shallow bays. Two-dimensional modeling was used to investigate...
Field Verification of Diffuser Performance
Effluent diffusers are used to gain relief from end-of-pipe acute toxicity criteria in NPDES water quality-based discharge permitting. Regulatory agencies require that the dilution provided...
Bridge Scour Vulnerability Assessment
Although the failure of the New York Throughway bridge over Schoharie Creek in 1987 has focused national attention on scour related failures, other failures reinforce the need for implementing...
A National Bridge Scour Data Collection Program
A study to collect and analyze field measurements of bridge scour is being conducted by the U.S. Geological Survey in cooperation with the Federal Highway Administration. The primary objective...
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