Guyana: Collapse of the Omami Mine Waste Dam | Brazil''s ...
Case Study Guyana: Collapse of Omai Dam Holding Mining Waste. Prepared by: Camille GaskinReyes, Ph. D, CLAS/SFS. Background. In August 1995, a dam holding cyanidefilled mining waste from gold mining activities collapsed, dumping more than three million cubic meters of effluent into the Essequibo River, one of Guyana''s most important rivers.