in arid and semi-arid environments, groundwater plays a significant role in the ecosystem. in the last decades, groundwater levels have decreased due to the increasing demand for water, weak irrigation management and soil damage. for the effective management of groundwater, it is important to model and predict fluctuations in groundwater levels. in this study, groundwater table in kashan plain ...

Scientists and engineers are exploring a new way to decontaminate toxic waste sites by literally turning up the heat on pollutants. The method heats the ground using electricity or steam, which mobilizes the contaminants so they can either be extracted from the ground and destroyed or actually destroyed in place. Among the targets for this method are pollutants such as creosote, solvents, and g...

On August 13, 1995, a slope above Shum Wan Road failed due to high rainfall and caused a 30-m section of Nam Long Shan Road to collapse. The slope consists of weathered tuffs with a clay layer on the surface ofthe failure. A hydrogeological study was carried out by saturated finite difference grid model, MODFLOW, for the slope at the Shum Wan Road area. From the ground-water model, it was found...

Profiles of ground water pesticide concentrations beneath the Nebraska Management Systems Evaluation Area (MSEA) describe the effect of 20 yr of pesticide usage on ground water in the central Platte Valley of Nebraska. During the 6-yr (1991-1996) study, 14 pesticides and their transformation products were detected in 7848 ground water samples from the unconfined water table aquifer. Triazine an...

A combination of ground water modeling, chemical and dissolved gas analyses, and chlorofluorocarbon age dating of water was used to determine the relation between changes in agricultural practices, and NO3- concentrations in ground water of a glacial outwash aquifer in west-central Minnesota. The results revealed a redox zonation throughout the saturated zone with oxygen reduction occurring nea...

A spill of gasoline occurred at an automobile service station in 1986. Oily phase residue in the subsurface has, for the past eight years, continued to release water soluble fuel hydrocarbons into the aquifer. The site was characterized for implementation of intrinsic remediation. The subsurface was a beach sand with sea shell fragments. The water table was near 1.3 meters below ground surface....

• Each table in the database has one column and stores the possible values for a ground fluent term. •Whenever there is complete knowledge about the term, the corresponding table has exactly one row. E.g., the ground fluent term door has only one possible value (Closed ) and so the table for door has exactly one row: Closed. •Whenever there is incomplete knowledge, the table has more than one r...

Some imidazolinone herbicides have been shown to be mobile in soil, raising concern about their possible movement to ground water. Three imidazolinone herbicides (imazamethabenz-methyl, 497 g ha(-1); imazethapyr, 14.7 g ha(-1); and imazamox, 14.7 g ha(-1)) commonly used in crop production on the Canadian prairies were applied to a tile-drained field to assess their susceptibility to leach when ...

background: the aim of this study was to assess the effects of road deicing salt on the quality of the ground water resources in hamadan province during winter season. methods: water samples were taken monthly from thirty wells located around the hamadan-asadabad highway. the quality of well water was examined by measuring amount of sodium, chloride, total hardness, total dissolved solid, elect...