Diagnosis of waste landfills by infrared thermography

Increasingly strict legislation concerning the management and storage of waste is leading to the creation of a new generation of landfills, as weil as to the remediation or closure of older sites. Thus there is the problem of the long term surveillance of the old sites and the control of the new one. The mass of waste is often a black box in which intense, complex and poorly understood physico-chemical processes occur. If they cannot be controlled, they must be regularly monitored in order to intervene as rapidly as possible if the process warrants it. The thermal activity of a site is directly related to exothermal chemical activity of waste. This chemical activity produces biogases who accumulates in some particular places. Landfill managers have difficulty in characterising site activity and its change with time. There are two phenomena to control : accumulation of biogases like methane and leakage in the new sites and increasing temperature with the risk of fire underground in the old sites. Infrared thermography can be used to establish this thermal activity. We'lI described this two kind of applications.