Inquip specializes in the following services:

Main Office

1340 Old Chain Bridge Road, Suite 400
McLean, Virginia 22101


Case Studies

Village of Lake Delton, State Project 6209-01-7


Relevance of Project

  • Deep cutoff wall
  • Use of Soil Bentonite Technique
  • Excavation with a combination of extended reach backhoe and hydraulic clamshell
  • Low permeability of the Backfill
  • Fast track project

Project Background

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.

Principal Client Issues

  • Fast track emergency work
  • Maintaining the specified backfill gradation


Inquip mobilized on site very quickly and was able to save one week on the scheduled duration for the installation of the cutoff. Inquip utilized borrow material to meet the specified gradation of the backfill.