INEOS Styrolution is issuing a precautionary notification as hourly benzene emissions on-site have been detected above 0.021 parts-per million (ppm).
As part of removal of benzene from the site, the company said it placed a monitor adjacent to Tank 8 and the road as part of degassing activities that will begin Wednesday.
The company said the elevated emissions "are predominantly caused by normal Tank 8 breathing," and that significant emissions are also being detected from the intersection adjacent to the monitor.
INEOS said notification is pre-emptive, and no adverse effects are anticipated with these elevated readings. However, neighbouring Aamjiwnaang First Nation has already asked some residents to evacuate as a precaution.
The company said elevated levels could be detected at the site between October 2 and 6, so additional notifications may occur.
INEOS said the Tashmoo Avenue facility is not the only source of benzene in the area.
