In a quartz quarry, the settlement basin dike wall (base width: 30 m, height: 4 m, ridge width: 10 m) broke for an unknown reason. The dike was fitted with an spillway composed of a rubber mat that prevented the basin from spilling. The accident caused no casualties. Ballast on the Paris-Toulouse railway line was washed away and rail traffic was interrupted for 6 hours. The VERT River was polluted. Both the dike and ballast were restored to their original conditions.