Temperature and Gas Pressure Monitoring and Leachate Pumping Tests in a Newly Filled MSW Layer of a Landfill

Abstract

Field test data on the simultaneous variations of leachate level, temperature and gas pressure in waste can be used in verifying the theoretical solution of coupled model of gas pressure and temperature in municipal solid waste (MSW) landfills. The correlation between the variations of these properties caused by leachate pumping is a major concern in the management of landfills. Therefore, temperature and gas pressure monitoring and leachate pumping tests were conducted in a newly filled MSW layer of a landfill located at Wuxi, southeastern China. The multifunctional extraction well and monitoring wells were designed to monitor the simultaneous variations of leachate level, temperature and gas pressure. The spatial and temporal distributions of these parameters and their correlation were investigated and analyzed. The results show that the highest waste temperature occurs near the leachate level. The gas pressures measured in the waste above the leachate level increase with depth. During the leachate pumping test, the temperature and gas pressure increase in the leachate level decreasing zone. When the leachate level has stably recovered, the temperature decreases slightly and gas pressure in this zone decreases to nearly zero. In addition, the MSW permeability of the newly filled MSW layer is calculated. The variation in the water content caused by the change in the leachate level affected the temperature and gas pressure in the waste. The temperature and gas pressure increased in the leachate level decreasing zone. The gas pressure was collectively affected by the water content and temperature in the waste.