ИСТИНА

The most common fire hazardous contaminations of areas are technogeneous spills of fuel and lubricants. This is especially dangerous for the territories of the former landfills for solid waste, where fill-up grounds can generate not only toxic but also explosive biogas. Therefore, for the implementation of housing development in this case requires the simultaneous reduction of gas generation and concentration of hydrocarbons (HC) in the ground. The safest way to eliminate oil pollution is biological neutralization, mainly aerobic. However, anaerobic conditions are formed at the depth of such fill-up grounds. The anaerobic conditions are rendering difficult activity of aerobic hydrocarbon-oxidizing microorganisms that enter into the composition of the vast majority of permitted for use in nature commercial bacterial HC degrading preparations. In this regard, the development of methods for the biological treatment of territories for housing construction from hydrocarbon contamination at a depth of 1 meter and below is relevant objective. Samples extracted from wells from the territories set aside for future urban development, where household and industrial waste, which contained an average of 8.5% of hydrocarbons, was stored for a long time were investigated. Such soils are capable of producing biogas for 59 years with the content of flammable methane in gas products from 8 to 36%. Housing development on such a territory without cleansing measures is not permissible. The combined soils from depths of 1.00 to 6.00 m, which were treated with the «Rhoder» biopreparation (R. ruber Ac-1513D and R. erythropolis Ac-1514D) were investigated. The effect of the electron acceptor Ca(NO3)2 in concentrations of 1.25%, 2.5%, 5.0% for anaerobic degradation of HC by aerobic hydrocarbon-oxidizing bacteria (1x109 CFU/ml) was studied. It was observed that under anaerobic conditions, when Ca (NO3)2 is exhausted, there is a risk of the development of indigenous anaerobic microflora of the soil — competing biological processes of sulfate reduction and methanogenesis. However, in the presence of an optimal dose of Ca(NO3)2 (2.5%), anaerobic degradation of hydrocarbons in the soil during the warm and cold seasons proceeds with a maximum degradation rate of k = 1.53 year-1 and 0.38 year-1, respectively. Thus, the complete decomposition of hydrocarbons and the gas generation phase will be completed within 1 year, while the volumetric content of the main non-flammable carbon dioxide gas will be 99%.