In 2008, the Wisconsin Department of Transportation issued a fast track project to replace County Hwy A. Hwy A was washed out earlier in 2008, when Lake Delton flooded. The soil bentonite slurry wall was 550 feet long and reached a maximum depth of 110 feet. The cutoff wall was excavated with a combination of Koehring 1266 hydraulic excavator and a KS3000 hydraulic clamshell attached to an 863 crawler crane. The soil bentonite backfill was mixed adjacent to the trench using a low ground pressure bulldozer. The specified hydraulic conductivity for the backfill was k £ 1×10-7 cm/sec.