Physicochemical Characteristics, Particle Size Distribution and Total Hydrocarbon Content in Soil from Abandoned Landfill Site in Igbogene, Bayelsa state, Nigeria

Most household and some industrial solid wastes end up in the landfill which is the commonest means of solid waste management in many parts of Baylesa state, Nigeria. This study assessed the physicochemical characteristics, particle size distribution and total hydrocarbon content in soil samples from abandoned landfill site in Igbogene, Bayelsa state, Nigeria by collecting samples from varying distances (50m, 100m and 150m) at a depth of 0-20cm and analyzed using standard methods. Results were in the range of 5.01 – 5.34 (pH), 0.73 – 0.98 meg/100g (Exchangeable Acidity), 2.45 – 3.48 meg/100g (sodium), 0.19 – 0.31 meg/100g (potassium), 3.94 – 5.33 meg/100g (calcium), 1.52 – 2.15 meg/100g (magnesium), 9.57 – 11.49 mg/kg (nitrate), 4.18 – 5.19 mg/kg (sulphate), 6.99 – 8.85 mg/kg (available phosphorus), 8.23 – 12.60 mg/kg (total hydrocarbon content), 76.48 – 100.25 mg/kg (chloride), 5.14 – 7.59 mg/kg (ammonium), 8.83 – 8.95% (clay), 2.70 – 3.10% (silt), 87.93 – 88.35% (sand), 2.62 – 3.58% (organic carbon), 4.51 – 6.16% (organic matter) and 0.22 – 0.33% (total nitrogen). Analysis of variance (ANOVA) showed no significant deviations (p>0.05) across the various distances for all parameters except for organic carbon and matter, total nitrogen, potassium and ammonium. In addition, most of the  nutrients showed positive significant relationship at p<0.05. This suggests that at large the activities of old landfill in the study area is not influencing the soil characteristics under study. Rather the apparent decline in value away from old landfill may be due to mobility level of minerals in the soil toward the southwest direction, which the cluster analysis clearly showed. Keywords: Physicochemical Properties, Environmental Contamination, Hydrocarbon Content, Landfill