With residents set to start returning to Fort McMurray in two days, the premier announced Monday that hundreds of undamaged homes in neighbourhoods hardest hit by the wildfire are not safe to live in.
Tests done near those homes show ash and soil in the area contain substances like arsenic and heavy metals.
“Unfortunately, I have to report today that the outcome of these tests indicate that undamaged homes in certain neighbourhoods are not immediately safe for reoccupation,” Premier Rachel Notley said Monday afternoon.
“I realize this will be difficult news for people to hear who were expecting to return to their homes later this week,” Notley said. “As always, safety and health remain our top priority.”
Though they were not directly damaged by the fire, a total of 567 homes have been declared unsafe for habitation.
Residents of those homes will be escorted in and allowed to gather personal belongings, but will not be able to stay.
The homes include 350 houses and 10 apartment complexes in Abasand, 183 houses and one apartment complex in Beacon Hill and 20 apartment homes and complexes in Waterways.
The premier estimated the decision will affect between 1,500 and 2,000 people.
The homes destroyed by fire have been sprayed with a composite material that hardens into a protective shell, acting as a protective barrier that keeps contaminants from ash and other debris from spreading through the air.
The material acts like a safety blanket, said Scott Long, executive director of operations with the Alberta Emergency Management Agency.
The blanket prevents cross-contamination by wind that could pick up the toxic ash and spread it into uncontaminated areas.
Australia has used the material for similar reasons, while California uses it to prevent soil erosion. Landfills around the world use the material, including the one in Wood Buffalo.
Heavily damaged areas of Fort McMurray have been closed off with more 30 kilometres of security fencing, the premier said.
The staged re-entry plans for the rest of the 90,000 evacuees is on schedule to begin Wednesday.