Insufficient community infrastructure, a lack of supervision and guidance, and isolation in general are the top risk factors for West Marin youth, according to a coalition of community leaders that surveyed coastal communities in a series of meetings held earlier this year. The group, founded in 2014 to reduce underage drinking and drug use, held four community meetings in Tomales, Point Reyes Station, Bolinas and San Geronimo to gather ideas about the best ways to…