The company in charge of the Co-op Refinery in Regina has pleaded guilty to violating the Occupational Health and Safety Act in connection with a 2011 explosion and fire.

A corroded pipe leaked, causing the explosion that injured dozens of people on Oct. 6, 2011.

Consumers' Co-operative Refineries Ltd. confirmed Thursday it has pleaded guilty to failing to ensure that all work was sufficiently and competently supervised at that time. No further comment was provided.

The Crown has agreed to withdraw four other occupation health and safety charges. That move was confirmed with a spokesman for the provincial ministry of justice who told CBC News that the rationale for the agreement would be addressed following sentencing, which is set for May 12.

The Oct. 6, 2011 explosion is also the subject of another — separate — legal proceeding where some of the injured workers are trying to proceed with a lawsuit against the refinery.

Tavengwa Runyowa

Regina lawyer Tavengwa Runyowa continues to press a legal claim for clients injured in an explosion at the Co-op Refinery. (CBC)

The workers' lawyer, Tavengwa Runyowa, told CBC News Thursday that he is disappointed that the other charges under the occupational health and safety law were withdrawn.

He said he will continue to pursue the company for his clients.

"The fact that this chapter is closed doesn't mean that the book of justice on this story is closed," Runyowa said. 

In Saskatchewan the ability to sue an employer is limited, under the Workers Compensation Act. Runyowa said his clients must first deal with the Workers Compensation Board.

"We still have a way to go to convince the Workers Compensation Board that this is the sort of case that should be heard before the courts," he said.

He said submissions on the issue will be made to the board next week.