You may have seen some recent media coverage regarding hydrogen cyanide (HCN) emissions at Suncor’s Commerce City refinery. At Suncor, we are always striving for continuous improvement across our business, including reducing emissions. Our employees and the community can feel assured that the Colorado Department of Public Health & Environment (CDPHE) has stated that modeled HCN concentrations near the refinery are well below known health risk thresholds.
I hope the following information helps you understand more about these emissions at our facility.
The refinery uses crude oil to make many products used by Colorado consumers. When we process crude oil into gasoline using specific equipment at the refinery (known as a fluidized catalytic cracker, or FCC), one of the by-products is HCN; this is true at many fuel refineries that use processing equipment like ours. What’s important is that we calculate HCN levels hourly and report our emissions annually to the required regulatory authority.
You may be wondering what is HCN? It’s naturally occurring in foods such as spinach and lima beans; it’s also present in fruits that have pits and seeds, including cherry, apricot and peach pits, and in apple cores and seeds. In its gaseous form, HCN is a light gas that rises and disperses in the atmosphere. The refinery’s vent stacks are built high into the air to allow for dispersion. Suncor is able to model the dispersion of HCN emissions, which shows that HCN disperses quickly to parts-per-billion levels that are below the most stringent limits set in the U.S. The modeling has also shown that HCN doesn’t reach ground level.
You may also be curious why this issue has come up. I want you to know there has been no change in how we are operating the refinery in relation to HCN emissions or in our reporting. Last year, Suncor asked CDPHE to add the HCN emission into the refinery’s “Title V” operating permit to align with our other air emissions. This approach makes sense because it simplifies reporting and brings efficiencies to the refinery’s air regulations under one regulatory agency.
CDPHE reviewed and issued the revised permit earlier this year, requiring Suncor to report the refinery’s HCN emissions data annually in the form of total emissions. Suncor is in full compliance with the limits and “maximum permissible” value CDPHE set for HCN. In fact, Suncor’s actual HCN emissions data in 2016 and 2017 were below the new limit.
I applaud the work of CDPHE, which diligently oversees and regulates the refinery’s air emissions. CDPHE makes the public health determinations for Colorado; it ensures that Suncor is meeting its requirements.
Suncor will continue to report all emissions as we have in the past. That won’t change. As well, Suncor will continue to work closely with all stakeholders, including regulators, emergency response agencies and the community. We’re trying to be more open. We do believe that a clearly stated HCN emissions limit in the refinery’s permit is the right thing to do and drives us to improve.
This story contains forward-looking information. Please see legal advisories for more information