The Best Management Practices (BMPs) for Sand Mining Operations; A Case Study at Linggi River Basin

The Linggi River Basin has a catchment area of 1,300 km2. The river passes through Seremban town and several industrial estates before it was discharged into the Strait of Melaka. The main tributaries include Pedas River and Rembau River. A large portion of the basin has been converted from forest to agricultural, industrial, commercial and residential uses has the potential to negatively impact on water quality within Linggi River. The objectives of the study is to develop a standard effluent disposal for sand mining as The Best Management Practices (BMPs) to enable the proclamation of the legislation and regulations by authorities. In order to meet these objectives, Hydrologic and hydraulic modelling have been applied. Pollution load modelling have been used for assessing the generation of pollutants and the subsequent runoff water quality. Modelling of the sand washing effluents was undertaken solely with the AD (Advection Dispersion) module due to the nature of the sediment to observed TSS measurements. Exclusions were applied to modelling of other point and non-point sources of pollution along these rivers. An in-bank 1D (MIKE 11) hydraulic model of the main waterway in the study area has been developed extending to the Straits of Melaka so that important tidal impacts can be included in simulations. The AD/ECOLAB model layout, which the modules are directly coupled to the hydraulic (HD) and hydrological (RR) modules and use the calculations of water level and flow. The Boundary conditions consist of Downstream, open concentrations (freely discharging to the sea), and Upstream and along the river channels. For the purposes of the riverine water quality assessment, four water quality parameters were considered, Dissolved Oxygen, Biochemical Oxygen Demand, Ammonia, and Total Suspended Solids. The findings of this analysis indicate that water quality within the Linggi River Basin typically does not meet Class IIA or IIB standard. The goal of environmental management is to minimize, prevent or mitigate adverse environmental effects of human activities to permit sustainable use of resources. Best (Environmental) Management Practices (BMPs) are possibly the most effective practical methods of reducing environmental impact levels. This implies BMPs might be a pragmatic way of addressing water quality from sand mining activities as well. There is great potential for improving riverine water quality in Malaysia through the adoption of BMPs for sand-mining operations.