The owner of a head shop and former medical marijuana smoking lounge in downtown Bangor pleaded guilty Monday in U.S. District Court to a marijuana conspiracy charge and admitted trying to hide cash proceeds from bank regulators. Christopher Ruhlin, 49, of Holden, owner of Herbal Tea & Tobacco and the former 13 Owls Club smoking lounge, located at 44 Main St., and his associate, Terrence Sawtelle, 49, of Bangor, were indicted on Sept.