Slurry Wall Construction Services
ENTACT brings experienced personnel and specialized equipment to our slurry wall construction projects. Over the last three decades, we’ve installed millions of square feet of slurry wall across the U.S.
Let Us Meet Your Challenge.
ENTACT has experience installing slurry cut-off walls using a variety of materials, including native and imported soil, bentonite, cement, slag and polymers, in various combinations.
We perform our work using seasoned operators and our own equipment, including long reach excavators, extended sticks and booms, slurry mix tanks, pumps and silos.
Put Us to Work
Our slurry cut-off wall construction services include:
A variety of slurry applications
We have experience with many types of slurry cut-off wall installations, including soil-bentonite, cement-bentonite, soil-cement-bentonite and composite materials. Depending on your site needs, we’ll recommend the best combinations of materials to meet your goals.
In-situ auger soil mixed column walls
Using our specialty auger equipment, we mix on-site soils with slurry reagents to create soil-cement walls. For added strength and groundwater protection, we can reinforce these walls with steel piles during construction.
Biodegradable biopolymer slurry trenches
Using biodegradable biopolymer, we construct slurry drainage trenches to collect or intercept groundwater.
Site dewatering and/or treatment injection systems
As a comprehensive service provider, ENTACT can remove groundwater or surface water from a site prior to excavation work.
“Funnel and gate” and Permeable Reactive Barrier (PRB) groundwater treatment systems
ENTACT is one of the few service providers that can install Permeable Reactive Barrier (PRB) systems. Often called “funnel and gate” systems, Permeable Reactive Barriers are groundwater collection treatment systems that use cut-off walls to funnel groundwater into a barrier.
Slurry Cut-Off Wall Construction Challenges. ENTACT Solutions.
Correcting a Former Wood Treating Site
Approximately 2,200 feet long and up to 45 feet deep
ENTACT implemented corrective measures at a 52-acre former wood treating facility that produced creosote-treated railroad crossties. After demolishing the on-site buildings, we installed a 2,200 linear foot soil-bentonite slurry wall to a depth of 45 feet below ground. This wall contained the source area and controlled groundwater migration from it. We also excavated and consolidated 17,000 cubic yards of PAH- and phenol-impacted surface soils, subsurface soils, and sediments and dewatered and backfilled a former water supply pond located in the containment area.
To close the project, we constructed a 7.4-acre engineered capping system, consisting of clay and topsoil, over the containment area. We also backfilled and revegetated the excavated areas, installed recovery wells to capture free product, and restored a ditch and surrounding wetland areas impacted by the corrective action.
Constructing 3 Slurry Walls at a Superfund Site
ENTACT completed slurry wall and cap construction at this Superfund site, constructing three soil-bentonite slurry cut-off walls around the perimeter of three perched water management areas. Installed at the FSD, FCD and DDA/LSD areas of the site, the combined walls were approximately 6,074 feet long, 3 feet wide and 17 to 45 feet in depth, meeting a permeability not greater than 1 x 10-6 cm/s.
We used an extended arm hydraulic excavator, equipped with 36-in wide V-Bottom Rock Ripper Bucket, to perform the cut-off wall excavation. A Jet Shear Mixer prepared the slurry to support the excavation. The proposed cut-off walls were keyed a minimum of 3 feet into an underlying impervious clay layer, with cut-off wall backfill consisting of suitable excavated soils blended with bentonite slurry and 2% dry bentonite addition to soil by weight.
Our activities also included the construction of a cap consisting of GCL or geomembrane, a drainage layer, geotextile and topsoil spanning more than 30 acres. In addition, we added storm water systems, drainage swales and revegetation to complete the project.
A Successful Slurry Wall Construction Leads to a Second Project
This client first hired ENTACT to construct a more than 9,000-foot long, 65-foot-deep soil-bentonite slurry wall keyed a minimum of 4 to 5 feet into the underlying competent bedrock. After the successful completion of the project, ENTACT was awarded additional work, including the construction of a 7,438-foot-long soil-bentonite slurry wall with an average depth of 29.4 feet and a total facial area of 218,677 square feet. The cut-off walls were required to minimize dewatering efforts and facilitate dry mining operations, while ultimately allowing mined pits to serve as a surface water storage reservoir upon decommissioning.
ENTACT’s scope of work also included locating and protecting (through concrete encasement) many subsurface utility lines that penetrated the proposed slurry wall alignments, as well as coordinating daily construction activities with the active mining operations.