As of September 2017, Mt Umunhum became one of the Bay Area's publicly accessible peaks.
Tuesday afternoon, the strong smell of vinegar and other obvious signs of a crew's clean-up effort provided evidence of where it all happened.
A few days prior, a liquid was poured across the surface of one rock at the mountain's peak.
"We had some visitors over the weekend who put some olive oil on one of the boulders atop the mountain," Leigh Ann Gessner said.
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Gessner is a public affairs specialist for the Midpeninsula Regional Open Space District.
It didn't take long for Mount Umunhum visitors to take notice, or track down those reportedly responsible for the vandalism.
A handful of South Bay neighbors and Facebook users posted to Jubilee Bridge Church's Facebook page. Many remained critical of the Morgan Hill church's actions.
South Bay neighbors are upset with a local church for its actions atop one of the Bay Area’s publicly accessible peaks— @MtUmunhum. A church group apparently poured a liquid across the surface of a rock, requiring Open Space crews to clean. Details at 11 p.m. #abc7now pic.twitter.com/4uo10ctpcd— Amanda del Castillo (@AmandaDTV) August 22, 2018
Page administrators and church pastors responded to comments, and acknowledged the church did something wrong.
"I was appalled to think that any type of religious organization would vandalize a public space in the name of their religion," neighbor, Rebecca Ewens told ABC7 News.
The long-time San Jose resident pointed to the irony in the issue.
Mount Umunhum is a sacred Native American site where tribes once connected with the spiritual world.
"There is no excuse for anybody to walk up here and not understand this is Native American land," Ewens said, referring to the posted signs that spell out the area's sanctity. "In addition, this space is for all of us to enjoy. It's for future generations."
Actions over the weekend gave Midpen officials an opportunity to educate those visiting the public space.
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"We ask folks who are interested in planning any type of group event to contact us beforehand," Gessner said. "So that we can work together and make sure that the natural environment and public safety is protected."
She explained the agency is not issuing permits for Mount Umunhum, as the site only recently opened. Currently, construction is still underway to create a more welcoming environment for guests.
She also shared habits visitors should adopt at any open space.
"Pack out what they pack in, do not leave any waste in the preserves," Gessner continued. "That makes it a more enjoyable experience for everyone and protects the environment."
Gessner didn't elaborate on whether Jubilee Bridge would be cited for its actions.
However, she said the olive oil incident was pretty minor compared to some of the more pressing issues the agency comes across. She elaborated and mentioned fire danger, general public safety and rescue efforts.
ABC7 News has reached out to the church to ask why its members poured anything onto Mount Umunhum rocks. Once we hear back, this article will reflect Jubilee Bridge's answer.