SUMMARY

Evaluating tranportstion process of pollutiants in pulp landfill soils in the Bản Cô mine, Quỳ Hợp, Nghệ An

Nguyễn Thị Hòa, Nguyễn Quốc Phi, Trịnh Thành, Nguyễn Phương, Nguyễn Thị Hồng

Mining operations in Việt Nam have caused many negative environmental impacts and shown affected to human health. The results of field surveys in Quỳ Hợp district (Nghệ An province) show that the greatest environmental pollution risk associated with the mining activities is the ability to disperse pollutants and heavy metals to the rivers and streams. Soil porosity in embankment of the waste disposal sites and heavy rain water in study area have made the problem more seriously for the soil and water environment. This paper used the CTRAN/W module in the GeoStudio software (Canada) to calculate the contaminant transpopt processes in soils overtime through seepage flow. Input parameters for the module were including soil properties and behaviors, groundwater level and amount of pollutant elements. This information can be collected through geological, hydrological and geotechnical data. The demonstralive results from Bản Cô mine have showed that the content of As in thc soil at the bottom of waste dump site moves through seepage flow in about 500 days (1.37 years) and As had reached the outer cdge of' the dump slope. In case of the seepage flows in 1,500 days (over 4 years), the As element can be founded at several locations on dump slope. The pollutants can go direclly to the surrounding stream (Huổi Đôn) and disperse to the extemal environment, resulting in harmful health effects of local people who were living downstream and around the mine.