Heather Knight and Peter Hartlaub spend a Sunday afternoon cleaning up trash in North Beach, after Refuse Refuse SF founder Vincent Yuen put out a Twitter call to Hartlaub, Knight and Hunter Pence, and the former San Francisco Giants outfielder answered. After the event, the Total SF hosts sat down with Yuen to learn his origin story, discover a new word (garbology!), find out why the west side of the street in S.F. accumulates three times as much trash — and why empowering neighbors to clean their streets has become Yuen's mission. Total SF has an audio tour in Golden Gate Park! Learn more and sign up at sfchronicle.com/audiotours Produced by Peter Hartlaub. Music is "The Tide Will Rise" by the Sunset Shipwrecks off their album "Community" and cable car bell-ringing by 8-time champion Byron Cobb. Follow Total SF adventures at www.sfchronicle.com/totalsf Learn more about your ad choices. Visit megaphone.fm/adchoices