Groundwater quality assessment of domestic shallow dug wells in parts of Tanah Merah district, Malaysia

Abstract

Groundwater resources have become an important fresh water supply due to its increasing demandsfor agricultural, drinking and industrial uses. Groundwater is often contaminated by the process ofindustrial development and suburbanization that has gradually advanced over time without anyconcern for environmental consequences. The objective of this study is to analyse the groundwaterquality of shallow dug wells in parts of Tanah Merah district by conducting quality assessment ofgroundwater using WHO and MHO guide lines. Groundwater samples were collected from dugwells uniformly spread out across the study area to investigate the major ion chemistry of thegroundwater as well as physical parameter. The major ion being investigated are sodium,magnesium, calcium, potassium, sulphate, nitrate, chloride and bicarbonates. Various methods havebeen were employed to determine the major ions concentration in the samples such as atomicabsorption spectrophotometer for cations, gravimetric method for sulphates, titration method forchloride and bicarbonates and colorimetric method for nitrate ion. From the analysed data’s, mostwells are safe for drinking purpose although quite a small amount of ion concentration has surpassedthe permissible limit set by WHO and MOH. The graphical presentation of major ion chemistryaids in identifying two types of groundwater. Ionic species such as Na-K-HCO3 and mixed typewaters are likely to occur in the groundwater system. The analysed major ions concentrationsindicates that majority of the shallow dug wells reported adequate or lower values compared topermissible limit which are safe and can be utilized for various domestic purposes includingdrinking. Several recommendations has been suggested to proliferate the groundwater quality suchas strictly monitoring and supervising the dissipation of waste such as pesticides, industrial effluentand domestic sewage into the aquifer.