2006: A paper presenting information on the worst groundwater pollution ever documented in the Southern Hemisphere. Orica’s Botany Industrial Park. The site was previously owned by British multinational ICI. As a result of decades of manufacturing activities and poor environmental practices on the site, chlorinated hydrocarbons leaked into the ground for a period from as early as 1940s to late 1980s. The carcinogenic chemicals mix with groundwater and eventually form a toxic plume that has spread 2 square kilometres covering the area under the houses of about 1000 residents. The plume is now gradually moving towards Botany Bay and is only a few hundred met res from the bay. If unchecked, the toxic plume will bring disaster to marine life and cause healthproblems to human and animalsin contact with the contaminated water in the bay.
https://www.prres.net/papers/Chan_Groundwater_Contamination_Case_Study.pdf