Smoke continued to pour early Thursday morning from the remains of a large wood debris fire that broke out late Tuesday near State Route 18 and Covington-Sawyer Road and created potential health concerns for nearby residents.

Firefighters from Kent, Maple Valley and King County Fire District 44 battled flames more than 100 feet high after arriving at the scene of the fire, a wood recycling facility operated by Rainier Wood Recyclers.

The blaze, which was reported at 10:30 p.m. Tuesday, measured about 175 feet by 50 feet and could be seen for miles when firefighters arrived, according to Kyle Ohashi, a Kent Fire Department spokesman.

After attempts to stem the fire with more than 2,000 gallons of water per minute had little affect, firefighters concentrated on the unburned portions of the pile to keep the fire from spreading further. A large track-hoe was used to separate the unburned wood from the burning material, Ohashi said.

Authorities expected the fire to continue burning for four to six hours. Firefighters remained on the scene to ensure that the blaze wouldn’t spread, officials said.

Efforts were expected to continue this weekend to extinguish the last of the fire. Officials said they were working with Rainier Wood Recyclers to douse the one remaining pile of burning wood. While the largest pile of wood involved in the fire was made up of large pieces, a smaller pile consisted of ground-up wood and was more dense, meaning that only the outer surface could burn while the inside of the pile smoldered due to a lack of oxygen, according to the Kent Fire Department. Once the pile burned down sufficiently, firefighters planned to pull it apart and extinguish the remaining fire, with a goal of finishing the job by the end of the weekend, officials said.

Kyle Ohashi, a spokesman for Kent Fire, said officials realized the increased air pollution caused by smoke from the smoldering wood but didn’t want to increase the danger to the community and environment by acting too quickly. As of last Friday, the amount of water needed to extinguish the fire would cause massive amounts of runoff into nearby Jenkins Creek and other waterways, he said.

Ohashi said officials decided against using large fans to speed up the burning process because of the potential for sending sparks into trees and dry grass.

Employees of Rainier Wood Recyclers were removing as much of the unburned material from the pile as possible to shorten the wait for firefighters to extinguish the fire.

People living or working in the area who were concerned about the massive amounts of smoke from the fire could do the following, Ohashi said:

• If possible, leave the area until the smoke ended.

• Close all windows and doors on homes or businesses to keep the smoke out.

• If anyone experienced respiratory distress due to the smoke, call 9-1-1 immediately.

The cause of the fire probably wouldn’t be determined until the fire was fully extinguished, Ohashi said.

Traffic delays on Covington-Sawyer Road were possible due to firefighting efforts.

A towering plume of smoke was easily visible from the fire site Thursday. A haze hung over State Route 18 that runs past downtown Covington and there was a faint smell of wood burning in the air.

Covington officials said they received a few phone calls asking about the fire but no significant inquiries.

Robert L. Myers, building official for Covington, said that despite the lack of work underway early Thursday morning all was well.

“The fire really didn’t have any large impact on the Costco project other than as a distraction,” Myers said in an e-mail.

Calls and e-mails to area fire departments who responded to the blaze were not immediately returned prior to the Reporter going to press.