"Towering over central Stonefalls, the great volcano known as Ash Mountain spews smoke and lava in a continual state of eruption. It's said to be honeycombed with caves and lava tubes, some of which hide ancient and perilous secrets."
Scamps are boiling up out of the ground, no doubt excited by the freeing of Balreth. Sergeant Jagyr asked for the Vestige's assistance in dealing with them. Collapsing the entrances to caves in Ash Mountain should do the job.