Deep aquifers in South and Southeast Asia are increasingly exploited as presumed sources of pathogen- and arsenic-free water, although little is known of the processes that may compromise their long-term viability. We analyze a large area (>1,000 km(2)) of the Mekong Delta, Vietnam, in which arsenic is found pervasively in deep, Pliocene-Miocene-age aquifers, where nearly 900 wells at depths of...

Grid refinement is introduced in a numerical groundwater model to increase the accuracy of the solution over local areas without compromising the run time of the model. Numerical methods developed for grid refinement suffered certain drawbacks, for example, deficiencies in the implemented interpolation technique; the non-reciprocity in head calculations or flow calculations; lack of accuracy re...

Groundwater development in fractured hard rock aquifers has always assumed a secondary role compared with that in unconsolidated alluvial strata or in soluble carbonate rocks. This is because of the nonextensive, irregular, nonisotropic, and inhomogeneous nature of the aquifer and the relatively small yields of water available from dug-wells or drilled bores. However, many of the highly populat...

A new method, passive flux meter (PFM), has been developed and field-tested for simultaneously measuring contaminant and groundwater fluxes in the saturated zone at hazardous waste sites. The PFM approach uses a sorptive permeable medium placed in either a borehole or monitoring well to intercept contaminated groundwater and release "resident" tracers. The sorbent pack is placed in a groundwate...

At the beginning of twenty-first century, the water crisis in the priority policy andmanagement is inside and outside of the country as principle thoroughly human, social,economic and political rulers of the country is considered abundant. The World Bank hasannounced that during 1960 and 2025, water resources in Middle East, from 3430 m3 for theeach person in year reach to 667 m3 because of pop...

Hydrochemical patterns across groundwater-fed wetlands, especially carbonate and redox gradients, can influence phosphorus (P) availability by controlling its distribution among different soil pools. We explored these linkages by comparing shallow (5–20 cm) soil properties along groundwater flowpaths in two rich fens, a marl fen, and a poor fen. Organic matter content, bulk density, and total e...

Lipid-filled semipermeable membrane devices (SPMDs) are receiving increasing attention as passive, in situ samplers for the assessment of environmental pollutant exposure. Although SPMDs have been successfully used in a variety of field studies in surface waters, only a few studies have addressed their characteristics as groundwater samplers. In this study, the performance of the SPMDs for moni...