Yeah, I know, the above clip from the 1997 documentary Volcano is set in a transit tunnel in Los Angeles, not San Francisco. And yet, it was the first thing I thought of when I learned that the San Francisco Police Department's radios don't work when officers are in the city's BART and Muni tunnels.

Would an operative radio have kept that poor guy from melting (or whatever) into the lava as he heroically leaped from that subway car? No, of course not. But as CBS 5 reports, operative police radios are key when the city is faced with a dangerous situation like the terror attack in Manchester (or, obviously, a volcanic eruption or other disaster).

San Francisco Police Chief Bill Scott freely admits that one of the city's big vulnerabilities are the "dead spots" in the departments radio system, which Scott says are "throughout this city and region."

The Chron reports that one of the most significant dead spots are BART and Muni tunnels, where "SFPD officers have to switch over to Muni or BART radio systems when they go into the tunnels."

“When police go into the tunnels, they are patched into and use the Muni and BART system,” SFPD spokesperson David Stevenson says. “It could be challenging, but it generally seems to work.”

SF Police Officers Association president Martin Halloran isn't so sure about that, saying that officers have "brought up the problems that they were having with the department’s new radios," but said that “It’s something that the city is working on.”

One solution, it appears, is a $78 million project to upgrade police radios and towers. Also on the horizon, a Department of Emergency Management spokesperson says, are communication relays in the tunnels that should be online by the end of the year.

But for now, it looks like we'll have to cross our fingers and hope for the best. For as former FBI agent and current KPIX 5 security analyst Jeff Harp says, "I can tell you as former commander of the SWAT team, that you have problems...It’s tough to communicate. That is the Achilles’ heel for any kind of operation.”