ORANGE ( — A Caltrans crew working near Irvine Lake Monday accidentally sparked a 214-acre brush fire that was 65 percent contained Tuesday.

About 60 firefighters will remain deployed Wednesday, mostly for “mop-up” duty, according to Orange County Fire Authority spokesman Capt. Steve Concialdi.

READ MORE: Southern California Airports To Get Millions From Biden Administration Infrastructure Law

A Caltrans crew mowing brush in the area of the 241 Eastern Transportation Corridor and Santiago Canyon Road apparently struck an object that caused sparks to ignite the vegetation, Concialdi said. The crew had a water truck following the mower, but their efforts to douse the flames failed.

“They were doing everything right, but it goes to show you how dry the vegetation was,” Concialdi said. “We’re in for a long, hard-fought summer and fall.”

READ MORE: CSU System Likely To Drop SAT, ACT For Admission

The evacuations went into effect just before noon Monday and affected about 10 to 15 people at the campground. Fifteen structures – including cabins – were also evacuated. Two former Irvine Ranch residences that had been scheduled to be demolished were destroyed by the fire, authorities said.

The fire broke out for unknown reasons late Monday morning near the 241 Eastern Transportation Corridor and Santiago Canyon Road, which was closed between the tollway and Silverado Canyon Road. Santiago Canyon Road is expected to reopen by 8 p.m. Tuesday.

The Orange County Emergency Operations Center activated a public information hotline at (714) 628-7085 for people to call for updates on the blaze.

MORE NEWS: Water Main Break Floods Cahuenga Blvd. In Hollywood Hills

(©2015 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Wire services contributed to this report.)