Multivariate statistical and spatial assessment of groundwater quality in the Tolon-Kumbungu District, Ghana

Abstract

The study was conducted to assess the quality of groundwater in 47 boreholes in the Tolon Kumbungu District of Ghana, using multivariate statistical and spatial techniques. The results indicate that physicochemical parameters exhibit wide variability. About 8.5% of the samples recorded pH outside World Health Organization recommended limit of 6.5-8.5. Approximately 43% of samples recorded conductivity levels higher than 1000 :S/cm, while close to 19% of boreholes recorded total iron concentrations above 0.3 mg/L. Approximately 3.4% of boreholes recorded arsenic concentrations above 0.01 mg/L. Alkalinity ranged from 28 to 766 mg/L CaCO 3 ; and groundwater in the area can be considered to have relatively high buffering capacity. Turbidity was associated with mineral matter suspension (Fe). Principal component analysis indicates that the data is a three-component system explaining 65% of the total variance. The first two components account for more than 50% of the total variance. Cluster analysis categorized the sampling locations into three spatially dissimilar groups. The natural hydrochemistry of the groundwater system appears to explain much of the variability of the data. However, a groundwater monitoring programme is recommended to characterize the variability of the parameters over longer temporal scales