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COMMERCE CITY, Colo. — Suncor recently announced that they completed their investigation following an incident that caused white ash material to fall from the sky on Dec. 11.

Suncor determined that too much gas oil, or torch oil, was added to their fluidized catalytic cracker unit (FCC) during start-up.

Because of this, catalyst was released from the unit and it fell on vehicles, buildings and equipment in the community. Suncor acknowledges that they should have suspended the start-up of the FCC once they realized it was not going as planned. Instead, they attempted to correct the issues while continuing with the start-up.

According to safety data sheets released by Suncor, the following substances made up the ash material:

GAS OIL NO. 2 AND NO. 3 (Atmospheric/Vacuum Gas Oil)
Super DESOX® (Catalyst additive)
FCC CATALYST (Equilibrium and Fresh Catalyst)
FCC MIDAS®-0926 (Catalyst)

Since the incident, Suncor says that they have updated their FCC start-up procedures to eliminate ambiguity.

Originally,  Suncor anticipated starting up the FCC again last week, however, they made the decision to do additional checks in the unit to ensure start-up conditions are ideal. Therefore, the start-up has been postponed, and Suncor will alert the public when they have a more solid timeline for the start-up.