By Bill Forry, Editor Bill Forry, Editor A rendering shows how an elevated boardwalk will carry a portion of the Neponset Greenway trail to Morrissey Boulevard, bypassing a hazardous expressway off-ramp. BSC Group graphic A long-awaited missing link to the 10.5-mile-long Neponset River Greenway trail was discussed during a May 26 online hearing hosted by the state’s Department of Transportation. The current preferred alternative for the connection between Morrissey Boulevard and Tenean Beach — which amounts to roughly 3,600 feet of trail, or roughly 0.7 miles— would improve pedestrian and bike connections. It includes a 670-foot boardwalk through the National Grid “rainbow” gas tank site with “bump-out” scenic overlooks offering views of Dorchester Bay and the Boston Harbor islands.