By Wilson Walker

SAN RAFAEL (KPIX) – The San Rafael Rock Quarry has existed for more than 100 years, but the conversation is now turning to how and when this operation should wind down.

Saturday was guided tour day for quarry neighbors, an annual event that lets them descend into the quarry itself and just gawk at it. The bottom of the pit, where the rock is quarried, is 300 feet below sea level.

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“It looks like you’re on the moon,” observed one visitor.

“I drive by it once in a while, and it’s amazing to see how deep it is,” said another.

Saturday’s tour also came with some more serious business: a neighborhood meeting about the future of this plant.

“It is supposed to wind down and eventually go away,” said Bonnie Marmor, President of the San Pedro Coalition.

Marmor leads the neighborhood quarry watchdog coalition.

“Homes were built in close proximity to this quarry because the prior owners had indicated that it was going to. That never happened,” said Marmor.

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“So our production levels have been lower over the last couple years,” said quarry spokesperson Aimi Dutra. “So we’re requesting more time to be able to remove those reserves that were there when we received that operating permit.”

Dutra, of the Dutra Facility, spent the day telling neighbors about how the plant works to be a good neighbor, cutting down on things like traffic and dust.

“We’re still complying with the 172 conditions that are there in place to ensure we mitigate any impacts to our neighbors,” Dutra explained.

She also laid out the plan for another 20 years of operation, and a multi-phase reclamation strategy for the site. So, if approved, the quarry would operate, as is, for some time.

“Until they run out of that 17.5 million tons of rock,” said Marmor.

Basically, they are going to keep chipping away on that northwest wall and one day, about 30 years from now, one last explosion will let San Francisco Bay come rushing in.

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The quarry’s application for the 20-year extension is now being reviewed by the county. It will eventually receive a hearing before the Marin Board of Supervisors.