State fire officials say coal smoldering underground near Healy has ignited four fires so far this season, including a new coal seam fire reported Tuesday.
The fires, as daunting as they sound, aren't unusual in the area and all are burning in areas already scarred by previous coal-seam fires. But officials say they're earlier than normal and blame warm, dry temperatures this spring that melted the snowpack quickly.
Dubbed the 2016 Louise Creek Fire, the most recent smoky blaze is burning in an old burn scar 1 or 2 miles north of another seam fire reported about three weeks ago, according to an update posted by the Alaska Division of Forestry Thursday on a wildland fire information site.
A helicopter dumped water on grass to the north of the fire to hold the flames within the burn scar, Division of Forestry spokesman Tim Mowry said Thursday. The new fire was putting up a "pretty good" smoke column amid high winds after the grass ignited, Mowry said.
The other coal seam fires measure 10 acres, 1 acre and 1/2 acre, according to the update.
State fire crews don't usually aggressively attack coal seam fires unless they threaten life or property. That's because noxious gases and the potential for firefighters to fall into burning coal seams during a ground collapse make direct attack unsafe, officials say.
Coal fires are common in the Healy area, where Usibelli Coal Mine is Alaska's largest coal mining operation.
"They're kind of an annual event," Mowry said.
The ongoing fires aren't having an effect on Usibelli operations, said spokesperson Lorali Simon.
The fires result from the underground smoldering of coal deposits north and east of Healy, where large areas are underlain with coal seams and coal seam outcrops, according to the Forestry Division. During warm, dry conditions, such as those the region is now experiencing, the fires sometimes surface and ignite grass surrounding the seam.
The fires are notoriously hard to put out and can burn for several years or even decades, officials say. Nine coal seam fires around Healy burned nearly 800 acres last summer.
Fire officials said they expect more coal-seam fires this summer.