REGINA -- Oil sludge was discharged into the City of Regina sewer system during an incident at the Co-op Refinery on May 22.

In a statement, the refinery said the incident was caused by high-winds.

“Early investigation is that strong and sustained winds leading up to the date of the incident resulted in stirring up sediments in the pond resulting in a discharge of sludge into the sewage system.”

The statement said the public was not notified of the spill because the “issue was contained.” It did not indicate how much oil was discharged. The refinery received word from the city that the issue had been resolved.

Unifor 594, the union representing the currently locked out refinery employees, said the incident is disappointing but not surprising.

“With the Co-op Refinery using inexperienced scab labour to operate an intricate and complex refinery, it’s these types of major incidents that we were afraid of when we were locked out back on December 5, 2019,” said Kevin Bittman, Local 594 President.

“I’ve worked at the refinery for 23 years, and windy conditions are not abnormal in Saskatchewan, so [the refinery’s] explanation doesn’t have merit. There is more to this than just weather.”

The union claims there have been numerous spills and releases with potential environmental impact, since the labour dispute between the two parties began in December.

In a statement, Unifor 594 said it will be calling on the Ministry of Environment to conduct a full investigation into this incident.

Co-op said it is conducting its own investigation and that the complex is taking measures to make sure something like this does not happen again.