Abstract:

Apatite ore mining and processing is one of the main mineral activities of Lao Cai province. According to the annual environmental monitoring results, most of the rivers and streams, which are flowing through apatite mining and processing areas such as O, Ngoi Dum, Ngoi Duong, Dong Ho and Coc streams … are polluted by COD, BOD, TSS, NO3-. Due to the long-term accumulation of contaminants, the level of pollution will become more serious if there are no suitable management measures. The integrated impact and risk assessment method (SAB) was applied for quantifying the environmental impacts and environmental risks in the study area. It also helps to determine the resolved priority environmental issues and thereby supporting managers and exploitation bases decide management and technical measures to overcome appropriate and effective environmental pollution. The results obtained in this study showed that the largest environmental risk came from surface water, the environmental impact and risk indexes of water quality as shown by a mean of 719.5 and 460.5 respectively. There were below the MAC limits (maximum allowed concentration). The air environment is primarily influenced by instant noise and suspended dust (TSP), although the impact and risk values were slightly (EI and ER: 210.2; 168.2). However, the environmental impact should be taken to minimize, that more 80% of the sampling rate exceeded 70% MAC limit. It means that the environmental risk was high for air. Therefore, the environmental managers in apatite mining and processing area should attention to controlling the concentration of pollutants in waste water, especially the parameters of COD, BOD, NO3- to reduce the impact to surface water systems and also having solutions to improve river and stream water quality