Soil Contamination of Heavy Metals in the vicinity of the Shincheon, Dongducheon City: Fid-Bau Portal

Soil Contamination of Heavy Metals in the vicinity of the Shincheon, Dongducheon City

Park, Jeong Min / Kim, Sun Joon

Cultivated soil and groundwater samples were collected and analyzed in the vicinity of the Shincheon which flows through industrial area of Dongducheon city to evaluate the pollution status of soil and groundwater and to determine the dispersion pattern of heavy metals in soils. Measurements of heavy metal concentrations in the soil sample were carried out using four pretreatment techniques; total extraction, 0.1N-HCl extraction, aqua-regia extraction and sequential extraction. By 0.1N-HCl extraction, all the samples contained less extent of guideline for soil conservation act in Korea. By aqua-regia extraction, one sample collected around the factory area showed higher concentration of Cr than the indicative value for further investigation and those of Cu and Zn than the reference values of the Netherlands. Concentrations of heavy metals decrease with depths in soils around the factory area and with distances from the stream. In addition, heavy metal contents of soils collected after wet season are much higher than those in dry season. The dominant fractions of Cr and Cu in soil are bound to organic matter/sulphides and residual fraction. Most of Pb and Zn exist in the residual fraction. Samples having higher contents of Cr and Cu than reference values of Netherlands by aqua-regia digestion show much higher proportions of organic matter/sulphides than the others. Except one sample showing slightly high content of Zn, metal contents of groundwater samples were within drinking water standard of Korea. Seasonal variation of metal contents, variations with distances from the stream and with depth, and acceptable groundwater quality indicate that soil contamination in the vicinity of the Shincheon is resulted from the flooding of sediments during rainy season rather than groundwater movement.