U.S. Forest Service officials could start releasing firefighters from the Apple Fire in the San Bernardino National Forest, nine days since it was started by a diesel vehicle malfunction, authorities said Sunday.
The fire has consumed 32,412 acres since July 31 and was 42% contained as of 7 p.m. Sunday evening, according to Cal Fire.
Saturday's fire activity was described by officials as minimal, with flames held within the established perimeter, but there was increased activity inside the perimeter as sparks caught unburned islands of vegetation.
Mop-up operations were underway in the Millard Canyon area.
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"Mop-up consists of looking for areas of flame and heat that are near the perimeter of the fire and making sure that they are extinguished; similar to stirring your campfire to make sure it is cold,'' according to a U.S. Forest Service statement.
One group of 10 firefighters was flown into the San Gorgornio Wilderness to look for ways to use natural barriers as containment lines, and another group will be flown in Sunday, officials said.
About 2,720 firefighters remained assigned to the battle, but that could change.
"As progress continues on fire containment lines, resources that are no longer needed will be released from the incident over the next several days," fire officials said. "Strike teams of engines that were utilized on the southern and western flanks will be reduced in number, but enough will remain to ensure adequate coverage."
Full containment was expected by Aug. 17.
The main fire progression was expected to continue to the northeast into the wilderness, with warmer and drier weather conditions expected to continue over the next couple of days.
The San Gorgonio Wilderness area remained closed.
A smoke advisory in effect Sunday due to the possibility of smoke and ash coming into portions of the Coachella Valley, the San Gorgonio Pass, eastern Riverside County and the eastern San Bernardino Mountains was extended to Monday, according to the South Coast Air Quality Management District.
Four homes and eight outbuildings have been destroyed. A firefighter was hospitalized after sustaining a head injury when he was struck by a falling tree branch on Thursday. No other details were available, including the firefighter's identity and condition.
An estimated 2,600 residences and 7,800 people were evacuated at the height of the fire. All evacuation orders in Riverside County have since been lifted.
Shortly before noon Friday, the U.S. Forest Service canceled an order that had been in place for the Oak Glen area just north of the boundary separating San Bernardino and Riverside counties, including Potato Canyon and Pine Bench. That was the last of the mandatory evacuation directives.
In San Bernardino County, non-mandatory evacuation warnings remained for Forest Falls, Morongo Valley, Rimrock and Pioneertown, according to the USFS.
The Whitewater Canyon community north of Interstate 10 and west of Highway 62 in Riverside and San Bernardino counties was added to the voluntary evacuation warning list Thursday.
In Riverside County, evacuation warnings were in effect for all areas east of Potrero Road, north of Morongo Road, west of Whitewater Canyon and south of the San Bernardino County Line.
Residents with questions or concerns about the fire can call 909-383-5688.