Bioremediation of Oil Contaminated Soil and Restoration of Land Historically Polluted with Oil Products in the Agricultural Circuit in the Plain and Western Hills, Romania

Abstract

Oil contamination in soil from a variety of sources, including accidental leaks, industrial activities, and improper waste disposal, involves disrupting ecosystems, contaminating water, harming human health, and diminishing agricultural productivity. Bioremediation is becoming the most important method accepted as a treatment for hydrocarbon-polluted soil using indigenous microbial flora, which aims to restore soils to their pre-hydrocarbon pollution characteristics. We will follow in our article to give some examples of good practices for bioremediation of oil-polluted soils in some sites in NE Romania. In a first step, all the oil extraction wells in NW Romania were mapped, both those in operation and those abandoned, reaching 695 wells. For 7 case studies, soil profiles were taken from the vicinity of the well column and from points close to it located in the well casing, for which the concentration of total petroleum hydrocarbons was determined. Using GIS spatial interpolation techniques, the theoretical concentration of petroleum hydrocarbons in the soil was determined. The polluted soil was transported to the bioremediation station, where it was exposed to bioremediation procedures, and the period and duration until the soil was brought to the accepted parameters in terms of allowable concentrations were analysed. The time required varies between 17 and 36 weeks needed for bioremediation. Following practical applications, it can be concluded that the time required for bioremediation is directly dependent on the initial concentration of pollutants and the number of chemical and physical interventions applied to the soil.