Application of Geostatistical Techniques in Groundwater Pollution Investigation in the Upper Denkyira East and West Districts

Year 2026, Volume: 21 Issue: 1, 19 - 39, 15.03.2026

Vıctor Oforı Agyemang

https://izlik.org/JA23KK78UX

Abstract

This study involves the application of geostatistical techniques to investigate groundwater pollution. Mixed water, NaCl, CaHCO3, and CaMgSO4 are among the groundwater types found in the districts. Three processes including rock mineral dissolution, ion exchange, and the effects of anthropogenic activities are major factors influencing the chemistry and overall quality of the groundwater in the area. Component analysis revealed six components that accounted for 81.55% of the total variation. Component 1 accounted for 38.16%, component 2 for 12.10%, component 3 for 11.43%, component 4 for 7.64%, component 5 for 6.85%, and component 6 for 5.38%. Six unique clusters were identified in the cluster analysis. Application of the water quality index showed that 38% of the groundwater was excellent, 38% good, 21% poor, and 3% very poor. The groundwater is unfit for drinking without prior treatment due to its low pH, high pH, high Fe, high Mn, and high PO43- levels. The quality of groundwater is impacted by both geological processes and anthropogenic activities like improper agrochemical application, galamsey, and improper waste disposal. The study has shown that geostatistical methods are reliable for assessing groundwater quality.

Keywords

Groundwater quality , Contamination , Ionic ratios , Multivariate analysis

Ethical Statement

The author declares that he has no conflict of interest.

Supporting Institution

No funding was received by the author

Thanks

The author is grateful to the Management of the Community Water and Sanitation Agency, Cape Coast, for making the data available for this study. The author also expresses gratitude to Priscilla Kyei Mensah (Mrs.), a graduate of the University of Ghana Business School, for her selfless assistance during this research.

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