On Wednesday August 20th 1997, an accident occurred at the grain storage facilities of the Société d'Exploitation Maritime Blayaise (SEMABLA) at Blaye (in the Gironde department). The accident mainly affected a vertical grain storage silo. The collapse of a major part of this facility, notably on the administrative and technical buildings, caused 12 casualties (11 fatalities and 1 injured). As part of the administrative inquiry that is held concerning any accident of this type, INERIS (National Institute for Environmental protection and Industrial Risks Management) was requested by the Ministry for National and Regional Development and the Environment to conduct an expert appraisal in support of the DRIRE Aquitaine (Regional Directorate for Industry, Research and the Environment for the region of Aquitaine).