Stream depletion, which is the reduction in flow rate of a stream or river due to the extraction of groundwater in a hydraulically connected stream-aquifer system, is often estimated using numerical models. The accuracy of these models depends on the appropriate parameterization of aquifer and streambed hydraulic properties. Streambed conductance is a parameter that relates the head difference ...

bazargan and poldasht plains are located in the north of west azarbaijan, northwest of iran. in this area, groundwater supplies main water demands. aim of this research is assessment of aquifer vulnerability for contamination potential on the basis of hydrogeological conditions of the study area. for this purpose the combined use of the drastic and geographical information system (gis) demonstr...

A 62-day controlled aquifer test was performed at the site of a new municipal well that penetrates a thick sequence of compressible basin-fill deposits in Mesquite, Nevada. Observation data were acquired from a high precision Global Positioning System (GPS) network to accompany the water-level data from the pumped well and a nearby observation well. The purpose of the investigation was to quant...

A new inverse method is developed to simultaneously estimate heterogeneous hydraulic conductivities, source/sink rates, and unknown boundary conditions for steadystate flow in an unconfined aquifer. Unlike objective function-based techniques, the new method does not optimize any data-model misfits. Instead, its formulation is developed by honoring physical flow principles as well as observation...

A freshwater lens underlain by saltwater exists beneath the entire northern Yucatan karst plain, Mexico. Water levels recorded in this plain, during the period June 1987 April, 1989, were used to map the water table, identify inland hydrogeologic boundaries, and estimate the thickness of the freshwater lens using the Ghyben-Herzberg relation. The water table under most of northwestern Yucatan i...

In-situ remedial strategies that involve the injection of a remedial fluid offer much promise for cost-effectively treating groundwater contaminants such as chlorinated solvent compounds, nitrated explosives, and perchlorate. The successful implementation of many in-situ remediation projects is dependant on the ability to develop an efficient and effective system for the delivery of the necessa...

A field experiment consisting of geophysical logging and tracer testing was conducted in a single well that penetrated a sand-and-gravel aquifer at the U.S. Geological Survey Toxic Substances Hydrology research site on Cape Cod, Massachusetts. Geophysical logs and flowmeter/pumping measurements were obtained to estimate vertical profiles of porosity phi, hydraulic conductivity K, temperature, a...

Management of groundwater contamination often involves conflicting objectives and substantial uncertainty. A critical source of this uncertainty in groundwater problems often stems from uncertainty in the hydraulic conductivity values for the aquifer. For a remediation solution to be reliable in practice it is important that it is robust over such potential errors. This paper presents the appli...

[1] Hydraulic tomography is a promising approach for obtaining information on variations in hydraulic conductivity on the scale of relevance for contaminant transport investigations. This approach involves performing a series of pumping tests in a format similar to tomography. We present a field-scale assessment of hydraulic tomography in a porous aquifer, with an emphasis on the steady shape a...