June started diving in 1952 with her husband, became a volunteer scuba instructor at the YMCA in 1954; served on the CNCA scuba committee; first woman nationally certified instructor in 1959; first female member of the YMCA National Scuba Committee; founding member Underwater Society of America and the American Littoral Society. She pioneered setting standards for diver and instructor certification. June instructed sport divers, police, fire departments, US Merchant Marine Academy cadets, and lectured extensively on the importance of diver training.