The Marcopper mining disaster is one of the worst mining and environmental disasters in Philippine history.[1][2][3] It occurred on March 24, 1996, on the Philippine island of Marinduque, a province of the Philippines located in the Mimaropa region. The disaster led to drastic reforms in the country's mining policy.[1]
A fracture in the drainage tunnel of a large pit containing leftover mine tailings led to a discharge of toxic mine waste into the Makulapnit-Boac river system and caused flash floods in areas along the river. One village, Barangay Hinapulan, was buried in six feet of muddy floodwater, causing the displacement of 400 families. Twenty other villages had to be evacuated. Drinking water was contaminated killing fish and freshwater shrimp. Large animals such as cows, pigs and sheep were overcome and killed. The flooding caused the destruction of crops and irrigation channels. Following the disaster, the Boac River was declared unusable.