Fire crews have 60 percent of a wildfire in the foothills west of Boulder surrounded, but fire managers say the remaining burn area is in steep terrain with no roads. On Saturday officials concentrated their efforts on strengthening and extending containment lines around the blaze in Lefthand Canyon. All residents evacuated by the fire on Friday have been allowed back into their homes as of Saturday afternoon. The cause of the fire remains under investigation. But the Forest Service has said it was human caused.