Olympic Triangle Habitat Restoration

Location: Tacoma, Washington
Client: Washington State Department of Natural Resources
Contract Value: $511,635

This intertidal remediation project was located on Commencement Bay in Tacoma, Washington and involved contaminated soil excavation and construction of a tidally influenced fish habitat.

After undergoing a pre-qualification process with the DNR and submitting a competitive bid, AEC was chosen to perform the removal and disposal of approximately 7,000 tons of arsenic-contaminated soil. We also removed a 500 ton concrete slab, installed geoweb and placed 1,300 tons of quarry spalls, cobbles and gravel as a sediment cap to control erosion.

Along with excavation activities, AEC imported and placed 1,500 cubic yards of topsoil to support planting efforts in marsh and riparian areas and installed/anchored eight (8) large woody debris structures as a habitat feature.

During early phases of the project, we assisted in work plan development, surveying, establishing environmental protection measures and erosion and sediment control best management practices (BMP’s). We performed strict marine and habitat protection measures during the course of the work to ensure the protection of the bay. During the entire project, AEC monitored water quality and performed water quality management to ensure minimal impact to the bay. All work was to be performed within the in-water work window between May 1st and September 1st.

Camp Withycombe Ranges Cleanup