An assessment on the impact of waste dump on soil physiochemical properties as well as some selected heavy metals concentration was carried out in University of Nigeria, Nsukka Enugu State Southeastern Nigeria. Field reconnaissance was carried out to select representative dumpsites and non-dumpsites (control) and two locations were selected: Odim and Engineering (ENG) dumpsite in the University of Nigeria, Nsukka Enugu State Southeastern Nigeria. The control sites were 50 m away from the dumpsites. Auger and core samples were collected in triplicates 10 m apart at different depths of 0-20, 20-40 cm from dumpsite and non-dumpsite for the determination of soil physiochemical properties. In addition, concentration of heavy metals in the soil was determined. Data obtained was analyzed using a two-way analysis of variance (ANOVA) in RCBD and the differences between means were considered significant at p≤ 0.05 using Least Significant Difference (LSD). The results showed that Odim textural class is predominantly sandy loam with while ENG dumpsite was sandy loam, loamy sand and sandy clay loam. There was significant difference in bulk density (BD), saturated hydraulic conductivity (Ksat), total porosity (TP), soil pH, exchangeable hydrogen (H+), exchangeable aluminum (Al3+), exchangeable calcium (Ca2+), iron (Fe) and zinc (Zn) across the location. There was significant difference (p ≤ 0.05) in the Ksat, organic carbon (OC), organic matter (OM), Al3+, Ca2+, sodium, effective cation exchange capacity (ECEC), and Zn across the soil depth. Across the interaction of location and soil depth, there was significant difference in BD, Al3+ and Zn on the soils from the study area. The soil from Odim was slightly alkaline to neutral (7.80-6.62) while in engineering, the soil was moderately alkaline to slightly alkaline (8.12-7.48). Odim dumpsite soil was higher in BD (1.56 g/cm3), Ksat (15.29 cm h-1), H+ (1.60 cmol/kg-1), Al3+ (0.23 cmol/kg-1) and Ca2+ (1.90 cmol/kg-1) than ENG dumpsite soil, BD (1.53 g/cm3), Ksat (14.39 cm h-1), H+ (1.40 cmol/kg-1), Al3+ (0.20 cmol/kg-1) and Ca2+ (1.77 cmol/kg-1). Also the results of heavy metals concentration are higher in Odim dumpsite than engineering dumpsite. The heavy metals are found in the decreasing order of Pd>Fe> Zn in the two dumpsites. Generally, the values of the heavy metal obtained from the studied dumpsites indicated low level concentration when compared with the permissible limit of heavy metal in soil recommended by World Health organization (WHO). However, the concentration of heavy metal on Odim dumpsite was higher (Fe =3.32 mg/kg and Zn =3.73 mg/kg) than that at engineering dumpsite (Fe = 2.20 mg/kg and Zn = 2.91 mg/kg). Lead (Pb) could not be detected, implying that the concentration of this metal is below detection limit or not present at all. The concentration of Pb in the dumpsite appears to not pose serious environmental problems at the moment. However, accumulated refuse at the dumpsites can influence soil physiochemical properties and reduce fertility status of the surrounding soils making it unfit for cultivation. This becomes necessary to construct a landfill around the waste dumpsite to enable proper handling and disposal of the waste.
Mmaduabuchi Faith Udeh (Fri,) studied this question.