Abstract

In-situ bioremediation is a technology, which has recently gained the attention of specialists for the clean-up of hydrocarbons. Organic chemicals are persistent and hard to deal with, because they are usually present in three forms: dissolved into groundwater, as free product over the groundwater surface, and adsorbed onto soil particles. The requirements for the bioremediation process to occur are the availability of microorganisms, a biodegradable pollutant, an electron acceptor, and nutrients. The shortage of nutrients in an available form for the microorganisms is very often a limiting factor for successful bioremediation in-situ. The main difficulties for the supply of nutrients usually come from the low permeability of soils. The feasibility of the application of electrokinetic processes, and, more specifically, the induced electroosmotic flow, for achievement of uniform distribution of nutrients for in-situ bioremediation in a natural clayey silt was investigated. Three different concentrations of ammonium nitrate solution were used. The experiment showed the efficiency of the electrokinetic method for supplying nutrients in a low permeability soil, especially for distribution of solutions with intermediate (1000 mg/L) concentrations. An advantage of the method is the prevention of the leaching of nitrates through the controlled electroosmotic flow.