Groundwater contaminant plume

When groundwater contaminant plumes are suspected of having significant depth as well as lateral distribution, a three-dimensional array of monitoring points is needed to identify and characterize such plumes. Thus, groundwater data must be obtained from a number of different locations and from a number of different depths at each location. As a result, either a large number of drillholes are required, each with separate instrumentation installed, or instruments must be combined and installed at multiple levels in each of a smaller number of drillholes. 

Groundwater contaminant plumes from accidental gasoline releases often contain methyl-tert-butyl ether. Experiments with certain soil microorganisms showed that a culture able to degrade methyl-tert-butyl ether did not degrade benzene and toluene. Further interactions were observed [468]. 

Figtire 5. Injection of an electron donor into a groundwater contaminant plume. 

Mulligan, A. E. (1999). Advective Control of Groundwater Contaminant Plumes Using Simulation and Optimization. PhD dissertation, University of Connecticut, Storrs. 

Mulligan, A. E., and Ahlfeld, D. P. (1999a). Advective control of groundwater contaminant plumes Model development and comparison to hydraulic control. Water Resources Research, 35(8), 2285-2294. 

The extension of SVE techniques to low-permeability soils was based on monitoring the vapor recovery rate and using the results of mini-pilot tests to adjust SVE system operation. The periodic mini-pilot tests provided information from individual SVE wells, including air flow, well vacuum, and hydrocarbon concentration in the extracted vapors, that was used to balance the flows. Wells with low hydrocarbon concentrations were shut off to focus remedial efforts on the most contaminated locations, and during some periods, wells with high flows were shut off to allow a more balanced flow from low flow wells or to provide hydraulic control along the periphery of the perched groundwater contaminant plume. 

Skaggs TH, Kabala ZJ (1995) Recovering the history of a groundwater contaminant plume method of quasi-reversibility. Water Resour Res 31 2669-2673... 

Christensen T. H., Bjerg P. L., Banwart S. A., Jakobsen R., Heron G., and Albrechtsen H.-J. (2000) Characterization of redox conditions in groundwater contaminant plumes. J. Contamin. Hydrol 45, 165-241. 

In addition, electromagnetic methods are subject to interference from many cultural features and the presence of nearby electrical fields. Finally, the ability of electromagnetic conductivity surveys to identify groundwater contaminant plumes requires that a significant electrical conductivity contrast exists between contaminated and natural groundwater (2). 

Figure 6. Cross sectional plot of conductivity values. Anomalous values of high conductivity, potentially representing the extent of an ionic groundwater contaminant plume, shaded with stipled pattern.

Electrolytic reactive barriers (also known as e barriers) consist of closely spaced permeable electrodes installed in a trench perpendicular to the direction of ground-water flow intercepts a groundwater contaminant plume, similar to PRBs. Rgure... 

Lopes M, Avillez G, Costa CN, Almeida JA (2006) Groundwater contamination plume monitoring in sealed waste dumps. Eng Geol 85 62-66... 

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