Though several pilots flying nearby spotted and reported the activity, scientists with the Alaska Volcano Observatory in Fairbanks quashed any fears -- there are no volcanoes, active or otherwise, in the area.
The nearest known volcanoes are in the opposite direction, on the west side of Cook Inlet.
Recent satellite imagery from the area showed no fire activity, so McNutt was without a clear explanation for the smoke.
But pilot Steve Schafer, who flew the area last week, has a theory. After seeing a continual trickle of rock or dirt coming down a steep mountainside, he thinks wind triggered a "perennial landslide" which kicks up huge plumes of dust.
"It's an unstable mountain, and it's kind of unraveling," said Matt Gray, who owns property in the area.
--The Seward Phoenix Log