TITLE:
Using Graphical and Multivariate Statistical Methods for Geochemical Assessment of Groundwater Quality in Oumé Department (Côte d’Ivoire)
AUTHORS:
Droh Lanciné Goné, Aristide Gountoh Douagui, Luc Bai, Bamory Kamagaté, Raymond Ligban
KEYWORDS:
Weathered and Fractured Aquifers, Physicochemical Quality, Oumé
JOURNAL NAME:
Journal of Environmental Protection,
Vol.5 No.12,
September
24,
2014
ABSTRACT: The large
demand for drinking water in Oumé Department in the Centre western of Cote d’Ivoire
is supplied from groundwater sources. This study investigated the geochemical assessment
of groundwater quality in Oumé Department by using a hydrochemical approach with
graphical and self-organizing maps (SOM) neural network methods. It was carried
out for identifying the hydrogeochemical processes related to groundwater quality,
conducting a hydrochemical evaluation of the aquifer systems and delineating the
various factors controlling the water chemistry and general suitability for drinking
purposes. To reach these goals, groundwater was sampled from 91 locations. Results
indicated that the groundwater sampled is acid (pH 4.27 - 7.10) and was weakly fairly
mineralised with electrical conductivity values obtained in the range of 95 - 1071
μS·cm-1. All calcium (6.8 - 127.59 mg·L-1), magnesium (1.08
- 29.00 mg·L-1), sulphate (0 - 74.9 mg·L-1), chloride (1.2
- 89.8 mg·L-1), sodium (1.2 - 94.27 mg·L-1) and potassium
(0.05 - 23.65 mg·L-1) concentrations and almost nitrate concentrations
were within of the recent acceptability and healthbased of drinking-water guidelines
set by World Health Organization (WHO). Moreover eleven sampling sites only have
concentrations of iron above 0.3 mg·L-1 which can stain laundry and cause
taste. In the water points, hydrochemical facies was calcium-bicarbonate (Ca-HCO3)
type which generally shows less-polluted water quality. Based on pattern analysis,
the inter-relationships among the groundwater quality variables due to the contact
with different geological formations on the basis of rocks basicity and acidity
were extracted and interpreted.