Community remains hopeful as search for missing 79-year-old San Mateo Co. woman continues

PORTOLA VALLEY, Calif. (KGO) -- The search continued Sunday on the Peninsula for a missing Redwood City woman with dementia. Seventy-nine-year-old Margaret Elaine McKinley has been missing since Thursday.

The large-scale search for McKinley has reached Day 4 with no sign of her.

"Over the last 72 hours, a total of 3,000 miles have been tracked by searches on the ground," said San Mateo County Sheriff Christina Corpus.

Corpus said 150 volunteers are still searching the 1,400-acre wilderness of Windy Hill Open Space Preserve in Portola Valley, and that this remains a rescue operation, not a recovery mission.

"Today, I had a briefing with our team, and we are not there yet. We will continue to look for Elaine. We have been on searches where we have recovered somebody alive after an entire week of them being missing," Corpus said.

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The search footprint widened west over the weekend beyond the preserve. Drone teams from Marin and Santa Clara Counties are assisting to expand aerial searches.

"Very steep terrain, tons of poison oak, lots of steep drainages," said San Mateo County Search and Rescue Volunteer Coordinator Ray Kruck.

Kruck said, so far, it's been exhaustive with many areas being retraced. He said he's still hopeful.

"Our team has high spirits and morale. Everyone is giving 120% of effort," Kruck said.

"They're going all out. I'm impressed. I've never seen anything like it. The more the days go on, it's scary for her. I feel bad," said Jeanne Ladley from Portola Valley.

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McKinley was wearing a red jacket and black pants when she went missing Thursday afternoon, during a hike with friends and family, when she got ahead of the group.

"I do know Elaine is a very fast hiker. If you turn around, she's zipping up the road. You have to chase her," said friend Linda Hook.

Hook has been standing vigil since Thursday along with McKinley's longtime partner, Kit Durgin.

CORNELL BARNARD: "What do you say to all these people looking?"

"Keep going, that's all you can say. We really appreciate it," Hook said.

The sheriff said search will continue on Monday if needed.