Bore and Well Water Quality Studies in The Tarkwa-Nsuaem Municipality and Prestea-Huni-Valley District, SW Ghana

Abstract

The quality of bore and well water within the Tarkwa-Nsuaem Municipality and Prestea-Huni-Valley District has been studied. The major cationic pollutants with concentrations above the WHO standards were iron, molybdenum, lead, mercury and manganese. High nitrate levels were found in boreholes at Akoon and Brenu Akyim which are communities close to active large scale mines where nitrates are major constituents of the explosives utilised. The study revealed that due to high microbial contamination, wells and boreholes at Tarkwa Community Centre, GAG Mile 7, Teberebie Roadside, Samahu Quarters, Dumasi, Abekoase, and Prestea Anyinam will require shock chlorination. Such a step can potentially reduce the numerous domestic water related sicknesses recorded in the investigation. Hydrochemical modelling using PHREEQC software indicated that some minerals had high saturation indices with the highest being goethite, hematite and ferric hydroxide at 7.38, 16.78 and 1.38 respectively within a borehole at Dumasi. The relatively high saturation indices of the iron oxides and hydroxides in the Dumasi samples explain the reddish brown precipitate formed when the samples are allowed to stand for a while. The results demonstrate that geological, mining and non-mining community related activities contribute to the water quality within the study area.