Landfill site investigation in the Tema metropolis using 2-dimensional resistivity technique

Abstract

Two-dimensional (2-D) resistivity survey was conducted at a site near Kpone in the Terna metropolis to investigate its suitability for a proposed solid waste disposal site. The resulting sub-surface resistivity pseudo-sections provided information about the overburden thickness, degree of rock fracturing, depth to fresh bedrock and an estimate of the excavation depth. Even though the hardness of the underlying geological formation was observed to increase with depth, the upper 25 m comprised stable argillaceous overburden mixed with isolated pockets oflateritic hardpan or iron stone of resistivity values ranging from 12-1,500 Q-m. This layer was underlain by east-west gently-dipping massive bedrock with little <>r no discontinuities with resistivity values ranging from 2,000-4,200 n-m. The total excavation depth was estimated to be 30 m below ground level. The site is considered geologically suitable for the intended purpose due to the absence of bedrock discontinuities to enhance contaminant transport to pollute the groundwater resources.