The month-old Tank Hollow Fire had burned more than 11,000 acres in Spanish Fork Canyon as of Tuesday, but crews were making steady progress in hemming it in.
Fire Information Officer Loyal Clark said the blaze, sparked by lightning Aug. 11 in the Sheep Creek drainage about 19 miles east of the city of Spanish Fork, was 78 percent contained.
About 120 firefighters were on the scene, but were not tasked to aggressive attack the flames. Instead, they were allowing it to burn within the rugged, steep and inaccessible boundaries of the blaze while focusing on extending and strengthening fire lines and dousing hot spots.