Groundwater Quality Mapping of an Open Municipal Solid waste Landfill Site

Abstract

The common practice of Municipal solid waste disposal method in developing countries is an unlined landfill dumping site. Due to this the natural resources land, water and air get polluted and also severely affected by the public living around the dumping yard. In this study, Srinivasapuram dumpsite in Thanjavur City Municipal Corporation area, India has been selected to investigate the quality of groundwater. Groundwater samples collected from 25 locations were tested as per standards for physical, chemical characteristics. The classical contour mapping method has been used to detect information from the recorded ground water quality data. Surfer 6.0 software has been used to convert the spatial data into equivalent contour map. Graphical method has been used to decide the area enclosed by each contour line. The water quality standards recommended by BIS and WHO were used to classify the critical regions based on the ground water contamination level. The water quality parameters such as pH value, Electrical conductivity, Total dissolved solids (TDS), Total Hardness (TH), Iron and Fluoride were considered for this analysis and other parameters were not included. All the collected groundwater samples the pH values are within the permissible limit of 6.5-8.5. The Electrical Conductivity vales range between 0.5mho/cm and 5.7mho/cm. The TDS values ranges between 200 and 3024 mg/l. The concentration of TDS is higher than the permissible level of the samples which are nearby the dumping yard as the contour lines are assembling around the dumpsite. The concentration of chlorides in all the samples under investigation is 12.4 to 1316 mg/l. It has been observed that concentration of total hardness (TH) of water samples varies from 118 mg/l to 2070mg/l. The presence of high concentration of iron and fluoride in the water samples adjacent to dumping yard indicate that it would have contaminated by leachate movement from MSW. The contour plots also reveal that the groundwater was contaminated as per the tests conducted for physical and chemical parameters.