U.S. Rep. Kevin Mullin joined dozens of supporters outside the archive Monday to condemn the proposed closure, calling it a threat to preserving the Bay Area's history.
"Closing this facility would dismantle access to our region's past with one single shortsighted decision," Mullin said. "Losing these archives would be a devastating loss to our community."
The San Bruno facility is one of three National Archives locations nationwide slated for closure under the administration's plans. Critics said the decision was made without advance notice or sufficient public review.
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"They did this with no public input and no transparency to the hardworking employees at these locations and no congressional oversight," Mullin said.
The archive houses hundreds of thousands of records documenting major chapters of Western U.S. history, including Alcatraz prison files, Angel Island immigration records, Chinese Exclusion Act documents and materials related to Native American communities.
Advocates said many of the records are irreplaceable and cannot be easily digitized or relocated.
"In these files are our precious family heirlooms, photographs, wedding certificates, detailed maps of home villages, materials too delicate and brittle to be scanned or transported," said Anna Eng, a member of Save Our National Archives and a lecturer at UC Berkeley.
Native American leaders said relocating the collection could disrupt access to records that have been important in documenting tribal histories and supporting legal claims.
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"Once the first box leaves San Bruno, we risk losing control of and access to records that remain essential to our communities," said Heather Hostler, executive director of California Indian Legal Services.
Hostler said the archive contains records that have helped tribes and Native families reclaim lost history and preserve cultural heritage.
"While these archives reveal the many injustices our people have endured, they have also helped us reclaim what was lost, preserve what remains and build a stronger future for generations to come," she said.
In response to the proposed closure, Mullin announced plans to introduce the National Archives Protection Act, legislation that would require congressional approval before any National Archives facility can be permanently closed.
The National Archives and Records Administration has not publicly detailed the reasons for the proposed San Bruno closure or announced where the records would be relocated. Requests for comment were not immediately returned.