In a telephone exchange, a 15 m³ tank of buried and corroded gas oil leaks. The installation was commissioned in 1977, the masonry of the protective enclosure is not watertight and a drinking water collection point is located at 75 m. The water table at 6 or 8 m depth is polluted. Pumping is suspended and water consumption is prohibited to the population. The firemen and the network operator provide drinking water to the 50,000 inhabitants of the commune for 10 days, the time needed to move pumpings and resume normal distribution. An appraisal is carried out, 50 to 60 m³ of polluted land must be treated.