VICTORIA -- Fire crews have contained a fire burning at an industrial facility near the Nanaimo Airport but officials expect the site to continue burning for several days.

More than 70 firefighters were called out Thursday to battle the blaze at a site owned by Schnitzer Steel Canada.

The Cowichan Valley Regional District, which is overseeing the fire response, says the fire has been fuelled by contaminated material, including a pile of tires that continue to burn.

It adds that the threat of the fire to adjacent properties is lessening as the wind dies down and 50 firefighters will continue their work to extinguish the flames.

The district says groundwater contamination as a result of the firefighting is now a concern.

"Water samples form various sites in the surrounding area are being sent for testing," the district said in a statement Friday. "Those results will be shared with impacted residents and other stakeholders as they become available by the respective provincial agencies."

The district is asking residents of North Oyster, Cedar and the town of Ladysmith to avoid using water as emergency crews continue to draw from the reservoir.

With files from The Canadian Press