Green space bawhahaha stupist question in years ! Production of corn sludge was far from green . Which is why they where located in one of the most polluted places in Canada. Residents of Sarnia and the Aamjiwnaang First Nation face a grave air pollution problem. There are 62 large industrial facilities in this border region, quite literally in their backyards. Approximately 40 per cent of Canada’s chemical industry is clustered near Sarnia in an area known as “Chemical Valley.” Located at the southernmost tip of Lake Huron on the border between Ontario and Michigan, the area has become one of the most polluted hotspots in Canada.