Compounds in the groundwater are transported through the soil as ions or charged particles by means of an electric field. The transport process plays a major role, especially when direct current is used where positively charged particles move toward the negative electrode and inversely. When using alternating current the soil is mainly heated, increasing the availability of the contamination. In addition, the temperature increase stimulates the biological activity. The mobilized contamination is removed using pump and treat or soil vapor extraction, and can sometimes be combined with natural and stimulated degradation
Electro reclamation is used for volatile organic pollutants (alternating current) and heavy metals (direct current). The technique is applicable to both saturated and unsaturated zone, and poorly to well-drained soils. Electro reclamation can be applied to both the source and the plume, but is in practice usually only cost effective for source areas (because of the intense character) with poorly permeable layers which can not be treated with other techniques.
The remediation period varies from several months to several years. There is a relatively high site disturbance as this technique requires a generator and an extensive network of electrodes. Also, the area must be fenced in because of the electrical potential differences in the soil.
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