F Pesticide Contamination Prevention Act authorrzed the California Department of Food and Agrculture to modify w.es of pesticides in areas where they have leached through soil to groundwater (Connelly, 1985). Leaching of agriculhuaI chemicals has been shown to occur during recharge of groundwater whereby water moves from the surface through the soil profile to a groundwater aquifer (Wehtje et a...

[1] The water table in southwestern Niger has been rising continuously for the past decades (4 m rise from 1963 to 2007), despite a 23% deficit in monsoonal rainfall from 1970 to 1998. This paradoxical phenomenon has been linked with a change in land use from natural savannah to millet crops that have expanded in area sixfold since 1950 and have caused soil crusting on slopes that has, in turn,...

Groundwater arsenic concentrations exceeding the federal drinking water standard are common in the southern Gulf Coast aquifer system in Texas, including in aerobic, unconfined groundwater which provides much of the municipal and domestic water supplies for the region. The objective of this study was to determine geochemical factors affecting the occurrence and distribution of groundwater As in...

A multitracer study of a small aquifer in northern Switzerland indicates that the atmosphere in central Europe cooled by at least 5 degreesC during the last glacial period. The relation between oxygen isotope ratios (delta18O) and recharge temperatures reconstructed for this period is similar to the present-day one if a shift in the delta18O value of the oceans during the ice age is taken into ...

Wastewater can be regarded as a valuable resource that can be re­ used in various ways, creating more sustainable societies which can benefit both human communities and the environment. An issue when using reclaimed water is the potential presence of health hazards such as microbial pathogens. The presence of pathogens can often impact on the type of water reclamation project selected. Artifici...

For an isotropic, homogeneous coastal aquifer, previous studies [Aust J Phys 26 (1973) 513; Water Resour Res 17 (4) (1981) 1222] have found that the mean watertable is influenced by the sea tide and will stand considerably above the mean sea level even in the absence of net inland recharge. This paper investigates the influence of the tide on the mean watertable for the case that the unconfined...

The Northern Guam Lens Aquifer (NGLA) presents unique challenges to modelers due to the complex hydrologic properties of its thick karst vadose zone. To meet these challenges, we developed VADOCHARGE, an analogue model based on the US Army Corps of Engineers’ Streamflow Synthesis and Reservoir Regulation (SSARR) model, to produce the effect of attenuated and lagged recharge through the vadose z...

Groundwater recharge from rainstorms can be vital for regional water resources. With the expansion of the need for more water in some specific regions under global climate change, groundwater is being pumped at a far greater rate than it can be naturally replenished. Considering that excess rainstorms could be utilized for groundwater recharge to lessen the declining tendency of regional ground...

One of the largest karst springs in North China, the Jinci Springs, dried up and has remained dry since 1994. We develop a correlation analysis with time-lag and a regression analysis with time-lag to study the relation between spring flow and precipitation. This allows us to obtain a better understanding of karst hydrological processes by differentiating the contribution of variation in precip...