Comparative Analysis of Contaminant Levels in Leachate and Soil from Young and Old Landfills

Abstract

The leachate generated in municipal solid waste landfills tends to have extremely elevated levels of organic and inorganic pollutants influenced by the age and variety of landfills. This research aims to conduct a comparative analysis between two landfills, Krubong Landfill Sites (KLS) and Bukit Bakri Landfill Sites (BBLS). Based on the standard limit set by the Malaysia Environment Quality Act (MEQA), the average values of the leachate parameters at KLS and BBLS were recorded. These parameters include pH (8.84 for KLS and 9.08 for BBLS), temperature (30.22°C for KLS and 30.06°C for BBLS), Chemical Oxygen Demand (COD) (3695 mg L-1 for KLS and 11289 mg L-1 for BBLS), Biological Oxygen Demand (BOD) (1695 mg L-1 for KLS and 3325 mg L-1 for BBLS), and ammonia nitrogen (1107 mg L-1 for KLS and 1390 mg L-1 for BBLS). The findings of this research suggest that the age of the landfill indeed influences the characteristics of leachate and soil. KLS, being a mature landfill, demonstrated low biodegradability. On the other hand, BBLS, being a young landfill, exhibited high biodegradability. The highest heavy metal concentration in the soil sample of KLS was Barium (Ba), with 409 ppm, followed by Zirconium (Zr) at 297 ppm and Vanadium (V) at 114 ppm. For BBLS, Zirconium (Zr) and Thorium (Th) were 209 ppm, Rubidium (Rb) was detected at 86 ppm, and Chromium (Cr) was 57 ppm. In overall essence, the age of a landfill significantly influences its characteristics. Newly established landfills tend to contain a greater quantity of organic matter compared to older ones.