EAGLE COUNTY, Colo. (CBS4) – The Sylvan Fire continues to move rapidly through the White River National Forest about 12 miles south of Eagle. On Monday morning, aerial mapping estimated the fire around 400 acres, by late Monday afternoon, it was just under 1,500 acres.

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“There’s a lot of dead and down [trees] in these spruce fur forests, and so it all just contributes to it,” said David Boyd, Public Information Officer for the White River National Forest.

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On Monday, Boyd said they were attempting to burn their own containment lines with plastic sphere devices (PSDs), dropped from helicopters, which ignite on the ground.

“There’s a ridge and a road between the lake and the fire, so we’ve actually done some of our own burning to try and put in some fire line to keep it coming over to Sylvan Lake and it’s been kind of moving south.”

Unfortunately, by late afternoon, Boyd said there wasn’t much progress with the PSD operation- the vegetation did not take, and the fire continued to move south.

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Fulford, an old mining town near the fire line, which is made up of small cabins, was on pre-evacuation notice but one property owner told CBS4 crews would not allow him back in as structure protection efforts were underway.

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As the fire continues to move south toward Pitkin County, the towns of Meredith and Thomasville were still on pre-evacuation notice but the sheriff’s office noted that it was closing the evacuation center at Basalt High School.

The fire, which was reported Sunday afternoon, was active through the evening. Crews expect Monday will be another busy night.

While more resources have been requested, crews across the West are already stretched thin.

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“The last couple of days have been really busy in the west with a lot of new starts and so we have orders for additional resources like hotshot crews and they’re already all being used, and so it’s hard to fill all the orders,” said Boyd.

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Boyd said the fire was likely caused by lightning, but an investigation is ongoing.

Jamie Leary