Sarnia refinery property line monitoring program in full swing

You can find results from the Sarnia refinery property line monitoring program on the recently launched Sarnia refinery page on Information on this page will be added in the future.

As shared in our June 2017 edition of Suncor Connections, as part of the new Ontario Ministry of the Environment and Climate Change (MOECC) Benzene Technical Standard, we have implemented a property line monitoring program for benzene.

Data summary

The Sarnia refinery’s property line monitoring system consists of 12 monitoring stations around the perimeter of the site. These passive fence line monitors are sampled and analyzed every two weeks. Data collected over the next three years will help determine our “baseline” emissions. That baseline will, in turn, help guide future improvements to reduce benzene emissions at our site.

Based on data from the first 10 months of our fence line benzene monitoring program, results for the Sarnia refinery (two week average) are:

  • Typical results are between 1 – 2.5 ug/m3
  • Highest reading to-date is 4.6 ug/m3

While our fence line data indicates values that are above the new annual limit (which reflects an incremental lifetime cancer risk of one in a million), it is within the range of risks considered negligible by the MOECC and other jurisdictions such as Health Canada and the United States Environmental Protection Agency (USEPA).

Benzene Emissions

In July 2016, the MOECC set a new annual limit for benzene emissions of 0.45 ug/m3 (micrograms per cubic meter).

While the new limit appears to be quite conservative, a Technical Standard was developed with the intention of providing facilities, such as the Suncor Sarnia refinery, an alternate way to comply by employing best-in-class controls on benzene air emission sources.

We take air emissions of all types seriously and continue to work hard to control benzene air emissions at our site. Some of the measures we have taken to reduce benzene air emissions at the Suncor Sarnia refinery include:

  • installing covers in our Waste Water Treatment plant to minimize emissions and odours
  • greater tank emission controls
  • enhancements to our Leak Detection and Repair (LDAR) program

Moving forward, we will focus on two key areas this year as part of the Sarnia refinery’s improvement plan:

  • Continued storage tank inspection and maintenance program (includes Technical Standard requirements)
  • Continue to strengthen the LDAR program

As of March 1, results from the property line monitoring program are being shared with stakeholders via the recently created Sarnia refinery page on

For information about Sarnia-Lambton air quality in general, you can also visit the Clean Air Sarnia and Area website.

This story contains forward-looking information. Please see legal advisories for more information.

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