The heavy metal contents and their dispersion patterns in stream water, stream sediments, land plants and aquastic larvae collected from the hydrologic system flowing via the wasted are dump of the Moak Au-Ag mine were investigated systematically in order to evaluate the environmental impacts of the abacdoned metal mine. The heavy metal content increases abruptly in the vicinity of the wasted ore dump, then attenuated with increasing distance from the mine area. Attenuating rates were stream water >stream sediments >land plants >aquatic larvae >stream water. Each element temds to be enriched selectively according to media; Zn>Cu>Cd>Pb in stream water, Zn>Pb>Cu>Cd in stream sediments and land plants, and Zn>Cu>Pb>Cd in aquatic larvae. These results show that the degree of enrichment and dispersion of pollutant exturbed from the wasted ore dump are different according to elements and media, and that the circulation system of materials of each medium is different. The heavy metals, especially Cu, Pb and Zn of polluted dowmstream sediments occur in high proportions of Fe-Mn oxides and organic bounded forms, which show high potential of a secondary pollution source. The content of heavy metals were degraded in various ranges. The Zn and Cu-polluted areas were widened whereas Fe and Pb-polluted area were reduced. In crops collected from the farm lands in downstream area, the pepper was more concentrated in all heavy metal than rice. The pepper showed some contaminated level in Cu(9.7ppm) and Zn(149ppm), and the rice in Zn(90ppm). However, both crops showed no significant level in Cd(<0.2ppm) and Pb(<0.5ppm)
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