RESUMO
Open dumping is the prevailing municipal solid waste (MSW) disposal technique in India. Unsanitary landfill releases leachate that contaminates valuable groundwater. Hence, the present study was carried out in the vicinity of the Saduperi open dumpsite, Vellore, Tamil Nadu, India, to explore the key factors that influences groundwater contamination. A total of 216 groundwater samples were collected between May 2021 and April 2022. These samples were categorised into four different seasons such as summer, southwest monsoon (SWM), northeast monsoon (NEM), and winter. Pollution indices such as the Leachate Pollution Index (LPI) and the Heavy Metal Pollution Index (HPI) were used to evaluate the contamination potential. The calculated LPI > 35 in all seasons indicates the prevailing poor environmental condition. It was observed that about 56% of the sampling site was affected by heavy metal concentrations such as Cd, Cr, and Ni. The HPI value was found to be more than the critical value of 100 in the 10 sampling wells for all seasons. Partial least squares-structural equation modelling (PLS-SEM) has also been carried out in this study to create a link between latent variables such as 'IOT Parameters', 'Leachate Parameters', 'Heavy Metal', and 'Groundwater Quality' which were quantified by the yield of R2 value. The R2 value of the sampling well ahead of the dumpsite and along the direction of the groundwater flow values ranges from 24.7 to 86.5% in comparison to the wells located behind the dumpsite, which are prone to more contamination due to migration of leachate. Hence, this present study shows various influencing factors that affect the groundwater quality.
