June 2, 2026, Construction Update

In early May, water levels at the construction site lowered enough that SumCo was able to repair the flow by-pass channel on the eastern side of the site. SumCo used pumps to move water away from areas where sediment excavation was needed and discharge this water to the by-pass channel and/or over the dam. When pumps were running, SumCo measured turbidity (amount of soil particles suspended in the water) in the discharge to confirm that it remained within acceptable limits. SumCo also has been lowering the dam in sections to assist with lowering water levels upstream. 

After the by-pass channel was reconstructed and water levels lowered, SumCo resumed sediment excavation.  Air quality monitoring at the site resumed at the same time that sediment excavation resumed. Completion of sediment excavation is anticipated by the end of Summer 2026. Once the planned amount of sediment is removed, SumCo will create the new stream channel and banks and install plantings.

Sediment testing has continued throughout the process, and sampling has not identified any material characterized as PCB remediation waste.