November 11, 2026 Construction Update – Sediment Excavation Completed

SumCo continued sediment excavation throughout the fall of 2026. In early November, removal of all sediment planned for excavation was completed, and all stockpiled sediment was transported off-site for disposal. Sediment excavation at the site is now complete. Because sediment excavation is complete, archaeological monitoring and quantitative real-time air quality monitoring have also ended. Throughout the sediment excavation work, there were no inadvertent discoveries of archaeological resources and no exceedances of air quality action levels. Sediment sampling did not identify any material characterized as PCB remediation waste.

The new river channel remained stable throughout the fall of 2026, and restoration of areas outside of the river channel is underway. SumCo is currently installing Bio-D block and geocell at the site to stabilize banks and adjacent areas. Installation of Bio-D block at designated bank sections is anticipated to be complete by late November, and geocells installation is anticipated to be completed in late December or early January. The stie will be stabilized with a seed mix and erosion control blanket over the winter. Final restoration plantings are scheduled for spring 2027, with final work anticipated to be completed by May 2027.