(Portland, OR) -- Cleanup continues at the site of the Centennial Mills building in Northwest Portland that was destroyed by fire. Nearby Fields Park remains closed, and debris continues to be removed from the park. A contractor has been going through the neighborhood picking up fire debris. There are concerns, because of asbestos in the building. The air near the building site tests safe. As debris is removed from the building site, the investigation into the cause of the fire continues. K9s have been sent inside, but no human remains have been located.