The characteristics of leachate and groundwater pollution at municipal solid waste landfill of Ibb City, Yemen.

摘要

Problem statement: Yemen one of the developing country suffering from water pollution. Landfill is one of the source of water pollution. There are several boreholes located close to Ibb landfill used for drinking water. A study of composition of landfill leachate and groundwater pollution was conducted at Ibb landfill, which is located at Al-Sahool area, north of Ibb City, Yemen. Approach: The leachate was sampled at three different locations of the landfill, at the landfill itself and 15 and 20 m downstream of this landfill. Groundwater samples collected from 5 boreholes to study possible impact of leachate percolation into groundwater. Leachate and groundwater samples were collected during dry season only, due to the excessive generation of leachate during this season. Objective of this study was significant to assess degree of groundwater pollution due to Ibb landfill leachate at Al-Sahool area. The leachate and groundwater were physically and chemically characterized by using spectrophotometer HACH, BOD Trak HACH, flame photometer (PFP 7) and Inductively Coupled Plasma of Optical Emission Spectrometry (ICP-OES) model Vista MPX. Parameters measured were pH, temperature, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Dissolved Oxygen (DO), Fluoride (F), Chloride (Cl), Sulphate (SO₄), Nitrites (NO₂), Nitrates (NO₃), ammonia-N (NH₃-N), heavy metals (Pb, Zn, Ni, Cr, Cd, Cu), major cations (Na, Mg, Ca, K, Fe) and biological parameters (COD, BOD₅ and coliform group bacteria). Results: The results showed that, leachate at landfill most likely in methanogenic phase, based on the alkaline pH value recorded (pH=8.46). The results also showed that 4 out of 5 boreholes were contaminated, where concentration of physico-chemical parameters are above the standard acceptable levels which required for drinking water adapted by Yemen's ministry of water and environment and by word standard. Conclusion: Therefore, landfill is dangerous for environment so government should do sanitary landfill to prevent further contamination to surface water, groundwater as well as soil.