Rational integration of principal component analysis in soliciting spatial ‘landmark-contaminants’ of Tanzania groundwater

Background: Regional landscapes createnatural barriers which restrict movements of groundwater within tectonic plates. This forms a vague groundwater containment which is likely affected by evaporations, fissures, and mineral dissolution. The effect is localized in such it accumulates certain kinds of chemicals resulting in a temporal build-up of unique contaminants. The unique or landmark contaminants destabilize the physicochemical and microbial composition of groundwater, resulting in the considerable risks upon consumption of such water. Methods: In order to establish spatial landmark contaminants, physicochemical, heavy metals and microbial content of selected water wells from Temeke and Nkuhungu wards were analyzed according to EPA Ireland methods. It was then, followed by bivariate correlation and principal component analysis (PCA) for data analysis. Results: It was observed that Temeke had a strong association between electrical conductivity and hardness while Dodoma had slightly higher alkalinity, pH values and coliform counts as compared to Temeke. A perfect linear relationship between electrical conductivity and total dissolved salts was further observed in Dodoma. The first principal component was electrical conductivity followed by dissolved salts merely from Temeke. The third and last principal components were respectively alkalinity and hardness from Dodoma.PCA proved to be a perfect tool for regional solicitation of landmark contaminants. Conclusions: The overall findings of this study identified that slightly high alkalinity and pH values were unique properties of Nkuhungu ground water as compared to low pH values and high electrical conductivity of Temeke ground water.