ANALYTICAL INVESTIGATION OF MINERAL OIL CONTENT IN SOIL DURING THE REMEDIATION PROCESS

An analytical investigation of mineral oil content from Ploiesti area was performed for monitoring the soil remediation process. Mineral oil hydrocarbons are among the most widespread contaminants in soil. Refineries, petrol stations, tank depots, pipelines and waste disposals are typical sources of this kind of contamination. The distribution of mineral oil hydrocarbons in soil is very heterogeneous depending on the depth and soil composition, particle size distribution, the content of organic matter, the mineral composition of clay fraction, pH. Investigation of contaminated soil, assessment of treatment processes and environmental monitoring of soil remediation require rapid analytical control which can be performed by GC. IR or gravimetric method function of the concentration level of the pollutants. Analyses were carried out on standard solutions and samples of soil contaminated with different kinds of commercial hydrocarbons. Gas chromatographic technique was used both for qualitative determination of mineral oil composition and for the qualitative evaluation of the pollution level, after preliminary pretreatment of the soil samples by extraction with acetone-hexane and clearing-up with Florisil. Soil samples were collected from 2 selected points from the polluted area and after the chemical and biological treatment. The analytical results offered the possibility to characterise the polluted site and to conduct the remediation process.