Soil Magnetic Susceptibility Properties as Indicators of Heavy Metals Pollution in “Bobov Dol” TPP Area (Bulgaria)

All the coal used in the power plants in Bulgaria are mainly high ash coals, which consequently leads to the release of big quantities of ash during their combustion. This cause a significant pressure on ecological status of the soil cover in the plants areas. Recently it has been proved that the magnetic susceptibility of polluted soils increases due to their enrichment with different metal oxides. The main goal of this research is to be analyzed the magnetic susceptibility values in the soils around “Bobov dol” thermal power plant (TPP) as an indicators of heavy metals pollution. More than 60 field measurements of the soil magnetic susceptibility were conducted around “Bobov dol” TPP. This measurements were evenly distributed around the power plan in accordance with the established grid network. The measured field value of the magnetic susceptibility range between 1.9358x10-6 SI and 475.233x10-6 SI. The higher values of the magnetic susceptibility are observed around the “Bobov Dol” TPP and along the transport line that transport the waste from the burning process to the nearby dump site. In addition frequency-dependent susceptibility - χFD% of the same samples have been measured and very good positive correlation between higher magnetic susceptibility values and lower frequency-dependent susceptibility have been found which proved that the high MS values are due to the presence of coarse spherical particles with anthropogenic origin.