Geoenvironmental Assessment of the Impacts of Ewu-Elepe Dumpsite on Soil and Groundwater Resources at Ikorodu, Lagos State, Nigeria

Abstract

The environmental status of the municipal solid waste dumpsite at Ewu-Elepe, Ikorodu Local Government Area of Lagos State was  investigated. A total of seventeen (17) samples consisting of twelve (12) soils, three (3) groundwater and two (2) leachate samples were  collected and analyzed for different parameters using Atomic Absorption Spectrophotometer (AAS). The results revealed that in the  leachate samples, all the heavy metals, Cl- , COD, salinity, and conductivity contents showed significant increase. The physicochemical  results for the groundwater samples agreed with the international standards for drinking water, except for high cadmium content  (0.009mg/l) recorded in the groundwater sample W1 which exceeded the NSDWQ and WHO permissible limits of 0.003 and 0.005mg/l  respectively for drinking water, and high manganese content (0.09mg/l) recorded also in W1. The results of soil samples from the  dumpsite showed that the concentration of all the heavy metals, Zn (23.5mg/kg), Cu (10.8mg/kg), Cr (14.2mg/kg), Ni (3.47mg/kg) and Pb  (19.0mg/kg) fall below the Sediment Quality Criteria ISQG-Low level and the Lowest Effect Range of the New York Sediment Criteria  except for Cd (16.60mg/kg) which is even higher than the High Effect Range of both the New York sediment Criteria and the Sediment  Quality Criteria that the soil within the dumpsite have been moderately impacted is further demonstrated by the application of  environmentric parameters treatment such as Contamination Factor (CF), Geo-accumulation Index, Enrichment Factor (EF) and Ecological  Risk Factor Analyses. The results of the sediment quality assessment are good evidence to confirm that the soil of the  dumpsite is highly polluted with cadmium (Cd), and moderately contaminated with lead (Pb). This study reveals that the solid waste  dumpsite is affecting the natural quality of the ambient environment. Therefore, indiscriminate dumping of solid waste at the dumpsite   should be prohibited.