Assessment of Some Lateritic Clayey Soils from Azara Northcentral Nigeria as Liners in Sanitary Landfill

Abstract

This study investigates the geotechnical properties of Azara clayey soils from Northcentral Nigeria for its potential use as liner in sanitary landfill. Six (6) samples were taken at about 2.5m interval each along exposed cliff and subjected to laboratory analyses.  The required parameters for soils to be considered as mineral seal such as grain size distribution, Atterberg consistency limits, maximum dry density and hydraulic conductivity were determined using the BS 1377 1990 standard. Results obtained show that the grain size analysis of the soils samples are silty clayeysand and clayeysand. The results of Atterberg limit show that the samples can be grouped as low clay soils and medium clay soils. Compaction test analysis shows that sample 3 has the highest optimum moisture content (OMC) value of 10.25%. Sample 2 has the highest maximum dry density (MDD) value of 1.95g/cm³ while samples 3 have the least MDD value of 1.52g/cm³ for modified compaction test. The results of hydraulic conductivity (K) reveal that sample 6 has the least value of 1.2 x 10^-8 cm/s, and sample 1 has the highest value of 3.0 x 10^-7 cm/s which falls within value of various waste regulatory agencies. In addition, three samples have adequate basic geotechnical properties and strength characteristics which suggest the potential suitability of the soils as mineral seal in containment facility for disposal of solid waste materials.

Keywords: Geotechnical, Landfill,  Mineral seal, Hydraulic conductivity, Nigeria.