| dc.description.abstract | In Thailand, the industrial mining contributes to the economic development of the country through foreign exchange earnings, employment and improved living standard of Thai people nearby the mining area. However, the processing water and disposal of mining tailings during its operation have become a long-term potential health and environmental risk. This study assessed and examined the impacts of closed lead-mining field on resident health and the surrounding environment in Thailand. A case study of the closed and abandoned lead mine located in the Klithy Creek of Kanchanaburi (here in after referred to as KC-mine) in the nation was examined.
Pollution from closed mines normally comes from two main sources: the discharge of wastewater during mining workings and the wasted materials spread on the surface of soil. During the operation, the processing water and tails of lead-mine was drained and discharged from working areas, that resulted in increasing the levels of lead in surrounding water bodies and soils. According to the estimation data of Pollution Control Department of Thailand in 2015 for the average diary dose (ADD) of lead based on the environmental pollution monitoring data of surface water, creek sediment, air, fish (muscle), rice, and vegetables in neighboring area of KC-mine, this study found that, in upstream residents, the lead-ADD of children is 6.5892 μg/kg/day and that of the adult is 3.9383 μg/kg/day. In downstream residents, the lead-ADD of children is 5.7360 μg/kg/day and that of adult is 3.5643 μg/kg/day. The lead-ADD of residents whether living in upstream or downstream areas are obviously higher than the tolerable daily intake (TDI) of potential impact to human health, i.e., TDI of children and adult are 3.517, which were provided by Joint FAO/WHO Expert Committee on Food Additives (JECFA). In addition, the most of pathway of contaminant distribution from high to low is the indirect water intake when swimming in the creek and bathing with the creek water (69.06%), that from ingestion of fish food (20.51%), ingestion of rice (9.20%), and from inhalation of air (1.23%) in sequence.
In view of the effort in restoration of contaminated KC-mining field by Analytic Hierarchy Process (AHP) basing on the opinions of authorized government personnel, environmental engineer, and residents living in Klithy Creek of Kanchanaburi, application of pollution control engineering and government intervention measures should be carried out.
The result through AHP process of this study reveals that the removal of sediments by dredging for remediation was most preferred by all expert groups because this remediation method requires less time to achieve efficient contaminant cleanup, and also around this site has suitable disposal sites to reduces transport-related operating costs. Nevertheless, the environmental engineering also prefers the monitoring natural recovering (MNR) due to this area is the lead potential site and highly uncertain of contaminated sediment lead to uncertainty of remediation dredging. It likely to adversely impact water quality and engineering controls may not be effective in protecting water quality which this is a main issue that can affect to health of residents. Furthermore, based on the AHP results and limitation, I preferred the environmental dredging method for the area of the high potential health risk. The vertical barriers wall was proposed for the area of the high potential for sediment mobility but low potential human health, and also continuously monitor the spread of pollution as well as the environmental rehabilitation policy should be carried out for the lead-contaminating area to ensure that the effects of resident health and environmental impact in the KC-mining area can be reduced to the minimum. | en_US |