Local groundwater in coastal aquifers in Shenzhen has experienced heavy pumping since the 1980’s when Shenzhen began to expand very quickly from a fishing village to a modern city but lacked a public water supply. Meanwhile, large-scale land reclamation was carried out to meet the needs of various urbanization projects. In this paper we analyzed groundwater from a coastal aquifer system in Shen...

Watertable waves generated by forcing from oceanic oscillations play an important role in the availability and quality of coastal groundwater resources. Here we present results from laboratory experiments which examine the influence of a boundary slope on the mass transfer from an oscillating clear water reservoir into a homogeneous, unconfined aquifer. The experimental forcing period is suffic...

Typically, when a new subsurface flow and transport problem is first being considered, very simple models with a minimal number of parameters are used to get a rough idea of how the system will evolve. For a hydrogeologist considering the spreading of a contaminant plume in an aquifer, the aquifer thickness, porosity, and permeability might be enough to get started. If the plume is buoyant, aqu...

A rule of thumb is presented to determine where variations in the discharge of a pumping well have a significant influence on the flow in an aquifer. The rule of thumb relates the period of the variation of the discharge to the distance from the well beyond which the transient effect on the flow in the aquifer is insignificant. For example, when an irrigation well pumps intermittently during th...

The release of colloids to groundwater was investigated in situ in an ironoxyhydroxide-rich, sandy aquifer. Groundwater amended with various solutes was injected into and immediately withdrawn from the shallow aquifer. Turbidity and colloid composition were monitored in the retrieved injectate. The response of the aquifer material to the amendments generally mimicked that observed in an earlier...

A head loss concept, new to the stream-aquifer interaction, is introduced for modeling laboratory observations. Using this concept, the equation applicable to fully penetrating streams is modified to account for the head loss at the entrance. The modified model is able to explain and fit the observed laboratory data correctly. Equations are proposed to calculate the hydraulic diffusivity of aqu...

Horizontal Permeability kh m 1.5×10 [10] 9×10 [10] 10 [1] Specific Storage SS m 5×10 [8] 2.7×10 [9] 10 [1] Aquifer Head h@t=0 m 0 [6] 130 [6] 5×10 [18] Aquifer Depth D m 55 [7] 2000 [6] 5×10 [1] Aquifer Thickness H m 16 [5] 3×10 [6] 5×10 [18] Kinematic Viscosity ν m/s 0.658×10 [2] 1.78×10 [2] 1.5×10 [18] Fissure Width w m N/A N/A 2.0 [1] Manning’s Number n None 0.012 [2] 0.05 [2] 0.04 [15] PARA...

A laboratory experiment was conducted to demonstrate the behavior of dense nonaqueous phase liquid (DNAPL) 1,1,1-trichloroethane (TCA) in a complex aquifer system. The system simulated consists of two unconfined aquifers separated by a low permeable bedrock perching layer that contains a fracture. In contrast to previous work by other researchers of DNAPL migration in hydrostatic conditions, in...

Near surface groundwater contamination is a widespread problem. The potential for contamination of deep aquifers in such areas depends on the vertical hydraulic gradient as well as the extent and location of interconnection between the upper and lower aquifers. In alluvial~ sedimentary environments, the geologic units are typically weakly connected lenses or layers of high or low conductivity w...