Mapping of Environmental Pollution Risk Induced by Open Dumping Practice of Municipal Solid Waste in Karadiyana of Sri Lanka Using Geographic Information System

Abstract

Quantification of environmental pollution risk (EPR) induced by open dumping practice of municipal solid waste (MSW) is important to improve MSW management practices and to provide effective countermeasures for mitigating EPR at the MSW open dumping site. This study targeted an open dumping site at Karadiyana, Western province of Sri Lanka and aimed to assess EPR by using geographical and hydrological information, water (landfill leachate and surface water) and soil quality monitoring for samples collected at the pollutant source (i.e., MSW dumping site) and its surrounding with monthly interval from June to December 2019 to cover both wet and dry periods. The maps of EPR induced by the pollutant source were visualized by analysing measured physicochemical parameters including heavy metals incorporating with interpolation and weighted overlay techniques of geographic information system (GIS). Results showed that the EPR mapharacterized well spatial distribution and seasonal variation of pollutants from the source. Especially, it was found that the pollutants flowed towards the Northwest and North from the pollutant source at the investigated site. It was also found that higher concentrations of phosphorous and heavy metals were observed from landfill leachate samples in dry season than those in wet season.  The findings in this study raise the mapping of EPR would contribute to take actions for establishing environmental sound waste disposal and to promote sustainable MSW management practice in Sri Lanka.