Identifying and Controlling Landfill Fires

Abstract

Factors leading to subsurface landfill fires and fire identification and control techniques are discussed. The paper is oriented towards completed sanitary landfill sites containing active landfill gas (LFG) extraction systems for either recovery or migration control purposes. The fire identification and control techniques discussed can be applied to both developed and undeveloped former landfill sites. The ignition and propagation of subsurface landfill fires are a function of factors which include waste composition and moisture content, available oxygen, and ambient pressure in the area of combustion. Identification and size of a subsurface landfill fire can be determined by unusual or rapid site surface settlement, surface venting of smoke, detection of carbon monoxide in extracted LFG, accumulation of combustion residue in LFG collection header lines, and elevated LFG temperatures. Subsurface landfill fire control techniques include excavation, smothering, and extinguishing with injections of water or inert gas.