Integrated Geophysical and Geochemical Methods for Environmental Assessment of Municipal Dumpsite System

Abstract

<p class="MsoNormal"> <span lang="EN-US" style="font-family:Verdana;">Leachate originating from open refuse dumpsite systems can be delineated through an integration of qualitative and quantitative methods. This study was designed to examine extent of leachate and pollution from one of the numerous open refuse dumpsites in Lagos metropolis. Qualitative assessment was determined using electrical resistivity tomography (ERT), vertical electrical sounding (VES) and induced polarization geophysical methods. Both ERT and VES methods revealed persistent low resistivity (1</span><span lang="EN-US" style="font-family:Verdana;"> - </span><span lang="EN-US" style="font-family:Verdana;">20</span><span lang="EN-US"> </span><span lang="EN-US" style="font-family:Verdana;">Ωm) of leachate to the depth above 35</span><span lang="EN-US"> </span><span lang="EN-US" style="font-family:Verdana;">m. The two methods were projected to produce 3-D view of the site which shows a NW-SE flow pattern of the leachate and possibly, the groundwater. IP values observed over the polluted zone was -2.9</span><span lang="EN-US" style="font-family:Verdana;"> - </span><span lang="EN-US" style="font-family:Verdana;">8</span><span lang="EN-US"> </span><span lang="EN-US" style="font-family:Verdana;">ms, indicating a sandy layer. Quantitative assessment was achieved by analysis of geochemical substances in the water samples taken from wells and boreholes in the precinct of the dumpsite. Here, we examine the macroelements, salts (sulphates, nitrates and chlorides), heavy metals, radioactive metals contents and physical parameters of the water samples. The analyses reveal the presence of these substances in the water and their strong correlations justified the provenance as the same. As part of the quantitative evaluation, physical parameters (pH, TDS, DO, salinity, total hardness, turbidity, electrical conductivity EC and temperature) of the water samples were also determined. The samples pH plotted in the acidic domain unsuitable for human consumption. Leachate flow direction was generated from the decreasing concentration of measured parameters (geochemical elements and physicals properties) in NW-SE direction which agrees with similar flow pattern deduced from ERT results.</span> </p

Hydrochemical analysis of groundwater quality along the coastal aquifers in part of Ogun Waterside, Ogun State, southwestern Nigeria

“…The Alluvial deposits form an unconfined aquifer (ranging from 2 m to 15 m depth Bold values indicate significant component loadings. below the surface) which is exploited by dug wells (Ayolabi et al, 2013). Other Formations like; Ilaro Formation (sandstone and limestone), Ewekoro/Akinbo Formation (shale and limestone) and Abeokuta Group (sand, clay, and shale) trend towards the northern part of the study area.…”

“…Furthermore, the north- central, north-east, southern and part of the eastern flank of the study area comprise of Alluvium (sand, silt and clay). The Alluvial deposits form an unconfined aquifer (ranging from 2 m to 15 m depth below the surface) which is exploited by dug wells ( Ayolabi et al., 2013 ). Other Formations like; Ilaro Formation (sandstone and limestone), Ewekoro/Akinbo Formation (shale and limestone) and Abeokuta Group (sand, clay, and shale) trend towards the northern part of the study area.…”

Vulnerability assessment of hydrogeologic units in parts of Enugu North, Southeastern Nigeria, using integrated electrical resistivity methods

“…Researchers have employed the electrical resistivity method in characterizing groundwater problems related to aquifer potentiality to yield water (4) , (16) , (19)(20)(21)(22)(23)(24) and contamination by delineating vulnerable zones, migration and the extent of contamination (11) , (4,(25)(26)(27)(28)(29)(30)(31)(32)(33)(34) . AVI has also been employed to quantify the aquifer vulnerability of an area and has been proven to be simple, faster and is widely used by researchers (35)(36)(37) .…”

Water quality assessment for groundwater around a municipal waste dumpsite

“…Several data analysis has been carried out on the physio-chemical, geochemical and geostatistical assessment of quality of groundwater [1] , [2] , [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] .…”