| Popis: |
Laboratory and field experiments were carried out for bioremediation of soils contaminated by fuel oil and motor oil. Bioventing was combined with the application of selected bacteria and dissolved nutrients. In the field experiments, soil gas was evacuated by air pumps from the permeable boreholes. The process was followed by both soil and gas analysis. Biodegradation of oil contamination and the microbial activity was measured by the oil and cell concentration in the soil. In 2 months, the oil content decreased considerably, and the cell number increased by one order of magnitude or more. The evacuated gas was tested for CO2, O2 and volatilized hydrocarbon content. The CO2 level proves the presence of biodegradation: a permanent high value about ten times higher than normal, could be measured for 2 months, followed by a slow decrease in the third month. Volatilized hydrocarbon content was the highest in the first 2 d. After a continuous decrease, it dropped under the threshold of measurability ... |
