Characterization of stabilized leachate and evaluation of LPI from sanitary landfill in Penang, Malaysia

The high demand in developing countries has generated a large amount of municipal solid waste (MSW), which has increased the number of sanitary landfills and dumping sites. MSW has been the key to producing raw landfill leachate (LFL). A high amount of organic and inorganic compounds that exist in LFL cause several contaminations to the surface and groundwater. This study aims to analyze and compare the outcomes of leachate characterizations from the Pulau Burung sanitary landfill (PBSL). Twenty-five parameters of LFL were investigated in this study. The average range of the parameters was temperature 31.5 degrees C, pH 8.12, chemical oxygen demand (COD) 1,566 mg/L, biochemical oxygen demand (BOD5) 179 mg/L, BOD5/COD 0.08, Ammoniacal nitrogen 207.5 mg/L, Turbidity 446.5 NTU, Color 1,633 Pt-Co, Total dissolved solids 5445 mg/L, and Conductivity 10.12 mu S/m. Moreover, heavy metals concentration were (As, Ca, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Mo, Ni, Se, Sr, Ti, and Zn) (0.039, 770, 0,024, 010, 0.51, 0.23, 8.6, 0.53, 644, 0.77, 0.05, 0.664, 0.055, 3,04, 0.256 and 1.039 mg/L respectively. The results obtained from this study were compared to Malaysia Environmental Quality Act 1974 and data from previous researches on sanitary landfills within West Malaysia. Additionally, the leachate pollution index (LPI) was conducted and evaluated based on certain contaminations in PBSL. The LPI value was 10.63, and this exceeded the LPI for the discharge standard of 5.710. Based on the leachate characterization and LPI values, the raw leachate was found containing a high concentration of pollutants and requires immediate treatment before being discharged to water sources.