CALGARY - Two months after fire and explosions ripped through its recently purchased asphalt refinery in Superior, Wis., Husky Energy Inc. says it still doesn't know when it will be able to restart the facility.

Spokesman Mel Duvall says investigations are continuing into the cause of the April 26 incident in which 11 people were injured and nearby homes evacuated while plumes of black smoke rose into the sky.

He says the Calgary-based company won't be able to fully assess damage and map out a recovery plan until the U.S. Chemical Safety Board completes its determination of cause.

Husky bought the 50,000-barrel-per-day refinery from Calumet Specialty Products Partners of Indiana for about $570 million in a deal that closed in November.

According to a website update posted Monday, cleanup efforts have progressed to the point that the off-site incident command centre has been moved onto refinery property. It says about 400 employees and contractors are supporting daily operations.

As of last Friday, Husky says it has received some 3,300 claims from local businesses and residents who incurred expenses or suffered losses during the incident, of which about 2,700 have been resolved.