Physical and chemical soil characterises integrating with GIS technique and regression models to optimize landfill location for various hospitals in Kirkuk city, Iraq

Leachate infiltration into groundwater is a major contributor to groundwater pollution, posing health hazards to neighbouring communities. Thus, this study aims to utilize Geographic Information System (GIS) procedure incorporated with regression models to assess soil characteristics and evaluate soil plasticity index as an indicator for landfill construction, specifically for medical and industrial refuse. Particularly, soil samples were collected from three different public hospitals within Kirkuk city, Iraq to optimize the best site for landfill construction. The research has focused on creating digital maps and analysing various collected physical and chemical soil characteristics. In addition, single linear regression model has been employed to evaluate the soil plasticity index in terms of individual physical and chemical soil properties. Furthermore, multi-linear regression model was applied to compute soil plasticity index benefiting from individual and combined physical and chemical soil characteristics. Precise associations between PI (plasticity index) and soil properties are determined, making it possible to indirectly quantify important soil swelling characteristics with low expense and effort to be used for optimizing landfill location. Moreover, using multi-linear regression consideration, various equations are analysed, demonstrating encouraging outcomes in predicting PI values with multiple R values ranging from 0.510 to 0.689. These models illustrate the benefit of including both physical and chemical soil properties to enhance the accuracy of PI estimation to give the chance for optimizing the landfill location depending on accessible individual or combined chemical and physical soil properties.