SAN FRANCISCO (CBS SF) — As a vaccine deadline approaches, even bigger problems for San Francisco’s struggling transit system could be ahead.

Less than a month before the deadline Muni leadership is sounding the alarm, saying the resulting layoffs could set city transit back more than a year.

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“As of last week, about 15% of our operators remain unvaccinated or have not reported their status, and they’re presumed to be unvaccinated,” SFMTA Director of Transportation Jeffrey Tumlin said Tuesday. “These individuals will be terminated beginning November 1st, unless they are fully vaccinated by that time.”

Tumlin was warning the SFMTA board that terminating all of the unvaccinated employees would mean even more service cuts for the depleted system, and not just in the short term.

“Our agency could lose over 300 operators, roughly the equivalent of the total number of operators we’re expected to train and hire over the next 18 months,” Tumlin explained. “This adds 18 months to the timeline for restoring pre-pandemic service levels.”

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“It’s already in a critical state, the service,” said Roger Marenco of Transport Workers Union Local 250-A. “It’s in a critical state at this moment, so why would you want to chop off your own leg.”

The union that represents Muni drivers has always been opposed to the mandate, and they’re still asking for an option of weekly testing. As for whether the city can terminate these employees for refusing the shot, experts say there is little question.

“Muni has a collective bargaining agreement so there are certain processes that it needs to go through that are different from many private sector environments,” said Former EDD Director Michael Bernick. “But yes, they can go through the process.”

When asked how the public might respond to further service cuts because of vaccine-reluctant Muni employees, union leadership said it’s unfair that passengers are not held to the same standard.

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“One of the things that I would say to the general public is, if the transit operators are required, and or forced to be vaccinated, then the general public should be as well. There’s no reason why one person on the bus, the operator, is the only person vaccinated,” said Marceno.