Evaluation of cadmium contamination due to stream sediment transport in Mae Tao creek, Mae Sot district, Tak province

Abstract

The Mae Tao subcatchment, the study area in this research, is known as the most worrisome site of cadmium contamination in Thailand. High cadmium levels in stream sediment are present, and this research concentrates on cadmium’s presence in stream sediment and its transport throughout Mae Tao Creek. The stream flow during storm events at 10 monitoring stations along Mae Tao Creek were surveyed, and the cadmium concentration and grain size distribution of stream sediment were quantified. The hydrodynamic results including water depth and water discharge were simulated using MIKE SHE coupled with MIKE 11, and stream sediment transport data were determined afterwards by the sediment transport module in MIKE 11. Finally, the sediment transport results and the measured cadmium concentration were calculated to evaluate the cadmium transport rate of stream sediment in the area. Nonetheless, due to the scarceness of supporting data, which can commonly occur in distributed model applications, the simulated results might still contain some degree of uncertainty and could be improved with more data collection. In conclusion, the spread of cadmium contamination due to sediment transport in the Mae Tao subcatchment mainly occurs during storm events. These storms intensify cadmium contamination problems not only in the area but also in conterminous areas