Characterisation of groundwater quality around Soluos dumpsite in Lagos, Nigeria

Groundwater quality in Lagos is susceptible to pollution due to infiltration from dumpsites. This study therefore assessed groundwater quality around Solous dumpsite in Lagos. Groundwater samples collected bimonthly from 20 wells for two years were analysed for pH, acidity, alkalinity, conductivity, total dissolved solids, total hardness, Cl−, SO42−, NO3−,PO43−, Pb, Ni, Cd, Zn, Cu, Fe, Mg, Ca, Na, K and total count of E. coli using standard methods. Multivariate statistical techniques (factor and cluster analyses) and phreeqC software were used to analyse the groundwater quality data. Seven principal components (PCs) extracted 85.3% of the total variance and four clusters of wells with distinct characteristics were revealed. Groundwater was classified as (Na +K) SO42− and (Na +K) Cl−. About 50% of the samples exceeded the WHO (< 1.0) limits for coliform count. The quality of the water investigated is doubtful, implicating the impact of dumpsite. Therefore, there is a need for regulatory measures on the dumpsite activities so as to reduce groundwater pollution.