NAVFAC NW contracted Tetra Tech to perform a repair of the shoreline protection system at Site 10 Northend at the Naval Magazine (NAVMAG) Indian Island, Port Hadlock, Washington. Over the years, wave action eroded the cutbank along the northeast boundary of the landfill, exposing metal and slag debris as well as fill material along portions of the beach. Through the Navy’s Installation Restoration Program, a Record of Decision (ROD) was signed for the installation of a permanent system to protect the site from erosion and to prevent further impacts to human health and the environment. The ROD for Site 10 also required O&M to ensure the effectiveness of this remedy. The system included a cap and shoreline protection system.

• Tetra Tech was responsible for planning, permitting, and construction management of the shoreline protection system, which was 590 feet in length and included three primary components: armor stone revetments, vegetated geogrids, and anchored log revetments.
• We used vegetated geogrids and log revetments to restore banks in riverine environments. The Washington State Departments of Natural Resources, Fish and Wildlife, and Ecology requested that these technologies be applied as a demonstration project in a marine area.
• We also removed all logs, anchors, and chains in the repair area (approximately 60 lineal feet); removed soil to facilitate the placement of armor rock at grade; placed geotextile filter fabric; placed armor rock; and placed habitat-mixed rock over the bottom portion and the toe of the armor rock. In all, 271 tons of armor rock and 80 tons of habitat mix were placed.
• The most significant challenge was completing the repair work during a 2-week “construction window” between high tide cycles. The repair work included beach armoring and mitigation to account for the loss of fish habitat. Several threatened and endangered species frequent this site. To comply with the Endangered Species Act, all work was required to begin and end within a 2-week period when fish spawning was not occurring. Approximately 255 tons of excavated material were stockpiled on site and later sampled and disposed in an off-site landfill.

Safety Highlight. Despite some unanticipated activities (e.g., unsuitable fill material), the project was completed without any lost time incidents and completed on schedule.