Suncor Sarnia is preparing for some spring maintenance.
The refinery said the process of shutting down units began Thursday evening in advance of the planned maintenance project.
The process is expected to occur over the next two weeks.
Suncor said during this time, residents may notice periods of increased flaring and noise.
"As a reminder, flaring plays a key role in our facility’s safe operation," read a notification from Sarnia-Lambton Alerts. "We are committed to completing this work safely while minimizing impacts to our neighbours, the environment and customers."
Perimeter air monitoring will be conducted during the shutdown process.