Slurry Walls

Slurry walls (also known as slurry trenches and cutoff walls) are non-structural barriers that are constructed to impede groundwater flow. An economical solution for a variety of environmental and civil groundwater control issues, they are used to provide cost-effective, long-term solutions for many groundwater control and groundwater remediation problems.

Slurry wall construction starts with the "slurry excavation technique", which was developed in Europe and has been used in the United States since the 1940s. Slurry wall (slurry trench, cutoff wall) excavations are normally performed with hydraulic excavators and their widths can vary from 1.5 to 5.0 feet. The slurry wall construction technique involves excavating a narrow trench that is kept full of an engineered fluid or "slurry". The slurry exerts hydraulic pressure against the trench walls and acts as shoring to prevent collapse. Slurry wall (slurry trench, cutoff wall) excavations can be performed in all types of soils, even below the groundwater table.

Bentonite slurry is the most common excavation fluid used in a slurry trench. Bentonite clay and water are combined in a colloidal mixer and the resulting slurry is pumped, through a pipe to the excavation site. The slurry trench can be backfilled with a mixture of excavated soil, dry bentonite, and bentonite slurry. Slurry walls wall (slurry trenches, cutoff walls) have become valuable groundwater remediation tools for containing underground wastes and for groundwater containment. Thousands of slurry walls (slurry trenches, cutoff walls) have been installed in the United States. With the assortment of valuable applications, those numbers are growing rapidly.

Slurry Wall

RECON is currently working in the third season of soil bentonite slurry wall construction at the PCS PotashCorp mine located in Rocanville, Saskatchewan, Canada. Upon completion in 2013, this will be the largest slurry wall ever constructed.

Project Features

• Specialty hydraulic excavator equipment and cranes
• Caterpillar 385 excavator that can excavate to 50 feet below grade
• Four Koehring 1466 excavators that are capable of excavating to depths of approximately 80 feet below grade.