FINAL ENVIRONMENTAL ASSESSMENT
Mouth of the Columbia River
Dredged Material Placement Sites Update
Clatsop County, Oregon and Pacific County, Washington
Issue Date: August 6, 2018
Interested parties are hereby notified that the U.S. Army Corps of Engineers, Portland District (Corps) has finalized the Environmental Assessment for the Mouth of the Columbia River Dredged Material Placement Sites Update: Clatsop County, Oregon and Pacific County, Washington (EA). The Corps is adding two sites to the network of placement sites for materials dredged from the Mouth of the Columbia River (MCR). The two sites include East Sand Island (ESI) at River Mile 5-7, which would be a shoreline placement site, and a second, in-water site offshore from the North Head Lighthouse (North Head Near Shore [NHNS]), along the Washington coast.
To facilitate shoreline placement at ESI, construction activities will selectively remove pilings and rock structures along the southern shoreline. Shoreline placement would occur in the fall of 2018 to address an area of localized erosion that would prevent the island from breaching and periodically in the future regularly supplement the shoreline. Adding the NHNS site would increase operational flexibility in the MCR by adding a near shore placement site, which would help retain sediments in the littoral zone to balance the regional sediment budget.
Environmental Document: The Environmental Assessment is available for public review and comment on the Corps’ Web site: www.nwp.usace.army.mil/Media/Announcements.aspx.
Agency Coordination: The Corps coordinated the Proposed Action with Oregon Department of Environmental Quality, Washington Department of Ecology, the National Marine Fisheries Service, the Oregon State Historic Preservation Office, and the U.S. Fish and Wildlife Service.
Assessment of the Need for an Environmental Impact Statement: The Corps has determined the action is not likely to result in significant effects on the human environment; therefore, an environmental impact statement was not prepared. A Finding of No Significant Impact (FONSI) was signed on August 6, 2018.