Seattle Tunnel Partners has been fined $2,000 because a concrete slurry spilled into city storm drains in Sodo last November.
The state Department of Ecology issued the penalty notice, dated June 27, and contractors have 30 days to pay it or to appeal. From the notice:
Ecology spokesman Larry Altose said the drains flow directly into Elliott Bay. In this case, the contractors released “Controlled Density Fill” because they wanted to seal off drains that were no longer needed — but some of the slurry went beyond the target. None of it reached the bay, according to KaDeena Yerkan, a tunnel spokeswoman for the state Department of Transportation. The four-page Ecology notice is linked here.
Construction teams typically inject CDF into soft soil, to prevent voids or slides that can damage nearby buildings. Another common use is to create a hard slab within wet or fill soils — so that a tunnel drill has a stable surface to grind through, as the cutting head moves forward under precise control.