May 11th, 2021 | The coastal federation has been promoting living shorelines in recent years as an environmentally friendly alternative to bulkheads. For the Pine Knoll Shores project, the federation hired Restoration Systems LLC of Raleigh to build an oyster sill for the effort. Dr. Weaver said as of Friday, they’ve built 15 feet of the 50-foot sill. “We have this new material, Biomason, we’re trying out with the sill,” Dr. Weaver said. She went on to explain Biomason is a product made of biological concrete mixed with oyster shells, giving it a “low-carbon footprint.”