Abstract:
The interference between natural and anthropogenic risk factors can trigger pollution phenomena, which can be transformed into local and regional ecological disasters. In the case of a fast transport vector (water and wind), pollution can also be cross-border. The ecological disaster produced in the area of sodium chloride extraction from Ocnele Mari, Valcea County caused such pollution. The implosion of some underground caverns with sodium chloride generated a wave of brine that was successively taken over by the Paraul Sarat River, the Olt River and the Danube River. The brine wave generated a local pollution phenomenon, later transformed into a regional and cross-border one. The initial flow of salt water was 3.0 – 4.0 m3/s, and the brine concentration was 30.000 mg/l – 250.000 mg/l. The discharged brine flow decreased over time to 0.15 - 0.20 m3/s, and the brine concentration to 225.0 - 250.0 g/l. The brine wave polluted the Olt River, the downstream reservoirs (mainly Govora) and finally the Danube River.
