Cause of explosion at Fort Frances school unknown, By LISA KACZKE, Staff Writer

FORT FRANCES — The Ontario Fire Marshall’s office is continuing to investigate the cause of an explosion and fire that occurred Thursday at J.W. Walker School in Fort Frances.
Piles of dirt overlaid with ice covered Keating Avenue Friday as a result of firefighters spraying water to extinguish the fire Thursday while other crews dug up the street in an attempt to turn off gas service to the school.
Evacuated residents were able to return home Friday while the Rainy River school district made accommodations for J.W. Walker students to return to classes Monday at other area schools.
Jack McMaster, director of education in the Rainy River school district, said he was thankful the incident occurred when school was not in session. McMaster did not have a cost estimate for the damage as of Friday and was waiting to hear whether part of the school needs to be rebuilt.
A leak in a gas main located under Keating Street migrated into the school, where an unknown appliance ignited an explosion, according to Rolf Waffler, investigator with the Ontario Fire Marshall’s office. The explosion then ignited a fire in the school.
Members of the Ontario Provincial Police were contacted by Union Gas to conduct traffic control due to a suspected gas odor at 10:58 p.m. Wednesday. The explosion that resulted in a fire occurred at 12:44 a.m. Thursday.
The International Falls Fire Department was contacted at 2:30 a.m. Thursday and responded with eight to 11 firefighters.
Damage from the explosion and fire likely destroyed evidence of what caused the fire, Waffler said.
The fire damage is mostly located in the gym of the school, with water damage to offices and the library. Water damage is also located in the subbasement area, Waffler said.
There was no smoke damage to classrooms, according to McMaster, who said hopefully the classrooms can be used within a few weeks.
If the damaged area is found to be not be structurally sound, it will have to be rebuilt, McMaster said. Rebuilding costs are expected to be covered by the district’s insurance provider.