The partitioning interwell tracer test (PITT) was introduced into the practice of contaminant hydrogeology in 1994, since which time about 50 PITTs have been conducted in the field. Confirmation of results of vadose-zone and ground-water zone PITTs by subsequent field testing of aquifers in Utah and New Mexico have demonstrated the reliability of the technique for operational purposes, i.e., th...

Vulnerability assessment to delineate areas that are more susceptible to contamination from anthropogenic sources has become an important element for sensible resource management and land use planning. This contribution aims at estimating aquifer vulnerability by applying the DRASTIC model as well as utilizing sensitivity analyses to evaluate the relative importance of the model parameters for ...

The vadose zone beneath the USDOE’s Hanford Site in southeastern Washington State (Fig. 1) received approximately 1 trillion liters (450 billion gallons) of liquid waste, some contaminated with radioactive and hazardous contaminants. Today, Hanford is engaged in the world’s largest environmentalcleanup project, and a variety of conceptual and mathematical vadose zone models have been developed ...

Aquifer drainage was numerically simulated by a coupled, unsaturated-saturated flow equation. The effect of the vadose zone on aquifer parameter predictions of classical hydraulic theory was investigated. Saturated-zone hydraulic theory was shown to be fairly robust in estimating the saturated hydraulic conductivity but less so in estimating drainable porosity, mainly because of the much tighte...

[1] Tide-induced variations in subsurface air pressure, mainly between 1.0 to 2.0 kPa, are observed in coastal areas in Hong Kong. A two-dimensional model which couples the two-phase air-water flow in unsaturated and saturated zones successfully reproduces the observed air pressure under no rain conditions. The simulation reveals that significant increases in air pressure depend on the tidal ra...

Getting into the heart of water movement vadose zone is essential due to direct impact on aquifer recharge, flood hazards, irrigation planning and resources management in general. Since soil profiles nature appear layers, present study accomplishes a deep investigation water’s motion through layers with different hydraulic properties. A series experiments were conducted laboratory where infiltr...

While ERT surveys are useful, Yeh et al. (2002) showed that uncertainties in tracking moisture movement in the Electrical resistivity tomography (ERT), during the past few years, vadose zone on the basis of ERT surveys alone can has emerged as a potentially cost-effective, noninvasive tool for imaging changes of moisture content in the vadose zone. The accuracy be quite significant. They report...