Summary

Acid streams resulting from mining activities from certain types of mineral deposits such as those at Rapu Rapu in the Philippines are highly toxic to the aquatic environment. The extreme acidity is harmful to most aquatic life and, even after neutralisation, the precipitate formed continues to affect aquatic organisms. Toxic elements, such as copper, cadmium and zinc are often associated with acidic mine drainage (AMD), contributing substantially to its devastating ecological effects. An outflow of acid mine drainage from the Lafayette mines in Rapu Rapu into the sea would undoubtedly affect local marine life. It could silt up corals causing coral mortality and cause the depletion of bottom dwelling organisms, which would have domino effects up the ecosystem, reducing the food sources available for animals at the top of the marine food chain, e.g. sharks. The toxic elements could also be taken up into the marine food chain, causing long term health effects to marine life, and some may bioaccumulate up the food chain. Although AMD can be treated at the mine to some degree, e.g. by neutralisation at source, this process is never fully effective. Furthermore, accidents with the treatmen