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USACE routinely dredges several projects on the Oregon Coast and Columbia River to maintain their federally authorized navigation channels.  In accordance with the Clean Water Act, USACE conducts sediment sampling and analysis at these projects prior to dredging to determine suitability for unconfined in-water disposal of dredged sediments and aquatic exposure of the post-dredge surface material.  There is an ongoing need in the Lower Willamette River (LWR) federal navigation channel (FNC) to maintain access for large, deep-draft commercial shipping vessels to Portland Harbor via this channel.  This project evaluates sediment quality for three critical shoals in the LWR FNC project area. 

The data quality objectives for this sediment characterization were to:

• Characterize sediments to be dredged from the project area in accordance with protocols found in the Sediment Evaluation Framework for the Pacific Northwest (SEF)
• Collect, handle, and analyze representative sediment from the dredge boundaries and in accordance with SEF protocols and QA/QC requirements.
• Characterize sediment to be dredged to determine its suitability for unconfined aquatic placement and aquatic exposure and to inform upland disposal options.
• Analyze representative sediment samples for physical and chemical parameters as outlined in the SEF.
• Analyze dredge prism sediments for chemical parameters listed in the 2017 EPA Record of Decision, Portland Harbor Superfund Site for riverbank soil/sediment cleanup levels and comparison to the navigation channel remedial action levels from the ROD by EPA.
• Analyze dredge prism sediments for chemical parameters listed in the Oregon Department of Environmental Quality (ODEQ) Ross Island in-water screening criteria (lagoon) for lagoon disposal and bioaccumulation screening levels.

ANAMAR was responsible for coordinating all field logistics, subcontracting a suitable vibracore vessel, leading and supervising all field sample collection and sample processing activities, coordinating shipping logistics with the laboratories to ensure samples arrived in good condition and were processed within holding times, performing data QA/QC, compiling results into tables, and identifying exceedances of screening criteria.

Roles/Responsibilities

• Coordinate field sampling logistics
• SAP review
• Lead and oversee sampling effort
• Lab coordination/sample custody
• Data QA/QC and reporting