Abstract

This research applied the groundwater quality index (GWQI) and principal component analysis (PCA) for assessing pollution levels and factors effecting groundwater quality of Pleistocene aquifer in Tan Thanh district, Ba Ria – Vung Tau province. Seventeen wells were colected in April (dry season) and October (rainy season) during 5 years (2012-2017). Nine parameters of water (pH, TDS, độ cứng, Cl-, F-, NO3-, SO42-, Cu2+ và Fe2+) were collected for analyses. The results of GWQI (dry season) divided into 17 wells in dry season with groundwater quality from good to very good which occupied to 82% databases, compared to 94% of rainy season. Meanwhile, the number of wells significantly changed from poor to very poor water between two seasons. PCA demonstrated that two specific factors, interaction of chemical components in river sediments and character of aquifer and anthropogenic, affected to the quality of groundwater in this study area. These explained 65.555% (dry season) and 61.562% (rainy season) of the variances. This result is provided specific information, and the useful tools in order to deal with the complicated databases, as well as zone the groundwater quality in the study area. This further help the authorities to plan suitable strategy for groundwater quality management.