as a third phase, thus enhancing the transport of strongly sorbing contaminants (McCarthy and Zachara, 1989). Until some two decades ago, it was believed that only the soil liquid and gaseous phases were mobile and could facilitate the transport of chemicals and nutrients through the vadose zone. It is now generally SOURCES OF MOBILE SOIL COLLOIDS accepted that also part of the soil solid phase...

Perchlorate contamination is a concern because of the increasing frequency of its detection in soils and groundwater and its presumed inhibitory effect on human thyroid hormone production. Although significant perchlorate contamination occurs in the vadose (unsaturated) zone, little is known about perchlorate biodegradation potential by indigenous microorganisms in these soils. We measured the ...

Although the accelerated transport of Tc, Cs, and U within the vadose zone beneath the 200-West Area of the Hanford tank-farm area has been recognized, the mechanisms responsible for the vertical migration of the radionuclides is unclear. Does horizontal stratification enchance the lateral movement of contaminants, which in turn enhances vertical perferential flow due to perched water dynamics?...

The U.S. Department of Energy Office Legacy Management is responsible for the long-term care and maintenance former uranium mill sites in United States. Prior predictions site flushing times (monitored natural attenuation) are not being met due to presence secondary contaminant sources associated with uranium-rich sediments vadose zone organic-rich near water table below tailings (tailings have...

Due to the anthropogenic activity, soil environment is deteriorated by various organic and inorganic contaminants a greater extent in Bangalore industrial area. The movement of heavy metals driven physical chemical properties soil. This contamination leads groundwater pollution through infiltration. In this study, an attempt made simulate transport like nickel zinc for one contaminated sites Ba...