High flaring was reported at Sarnia's Imperial Oil refinery late Wednesday morning.
Aamjiwnaang's Notification System reported that there had been a unit upset and a Chemical Valley Emergency Coordinating Organization information notice had been issued.
Imperial spokesperson Kristina Zimmer, left a message on the Community Awareness and Emergency Response Line just after 11 a.m.
"There is higher than normal flaring at our facility today, due to an upset in a process unit," she said. "We are working to resolve this issue. There is no action on the part of the community at this time."
An all-clear was issued at 11:42 a.m.
Further information was not immediately known.
