Many techniques of soil bioremediation enhancement have been developed recently. Two of them are application of weak electric field which induces favorable electrokinetic phenomena in the soil environment and surface active agents application which increase the biodegradation degree of poorly soluble contamination. During experiments the influence of the electric field and surfactants (biosurfactants, non-ionic and anionic surfactants) on the Pseudomonas putida and Bacillus subtilis bacteria migration in soil was determined. The intensity of the biodegradation of contamination was also estimated. The results show substantial impact of the electric field and surfactants on the intensity and direction of bacteria migration in soil as well as on the intensity of the contamination biodegradation.

TCE artificially contaminated soil was cleaned under anaerobic, reductive conditions. A laboratory scale treatability studies were carried out to determine optimal physico-chcmical and microbiological parameters for biorcmcdiation process. Upon treatability studies results a sewage sludge mixture was chosen as a microorganism's source. The chlorinated solvents contaminated soil bioreactor (CSCS bioreactor) was designed and built. It consists of a 6 m3 reactor vessel, a gas recirculation system, a leachate recirculation system and a data acquisition system. The bioreactor vessel was designed as a continuous gas flow packed bed reactor. During 210 days 4 Mg of soil containing approximately 350 mg TCE/kg of soil has been completely remediated under anaerobic conditions. The obtained results indicate that the stepwise dechlorination of TCE to ETH occurs in the bioreactor. Increasing amounts of chloride in the leachate were correlated with dechlorination.