In-Situ Solidification/
Stabilization (ISS) Services

ENTACT offers 30 years of on-site waste treatment, soil mixing, and soil improvement experience, combining expert knowledge with proprietary technology to effectively treat and strengthen your site.  

Let Us Meet Your Challenge.

As one of the most experienced ISS providers, ENTACT can treat your impacted site with either our proprietary reagent blends or more conventional applications. We hold several mixing equipment and reagent patents, reinforcing our innovation and commitment to treat contaminated soils, sludges and sediments successfully. We also have the in-house expertise and capabilities to improve the strength properties of clean applications soils and/or dredged fill to facilitate site development in coastal areas associated with expanding new petrochemical plants and constructing new Liquified Natural Gas (LNG) facilities.

ENTACT clients also benefit from our in-house bench scale treatability lab, where we can develop the solution and identify the equipment necessary for effective full-scale operations.

In-Situ Solidification/Stabilization Benefits:

Put Us to Work

Our ISS services include:
Contractor Performing In-Situ Stabilization/Solidification

Treatment reagent, formulation and dosage testing

Because we have extensive experience with both conventional solutions and reagents developed in-house, we can identify and test the best formula and dosage for your site needs.  We are able to create scalable solutions that can be confirmed through pilot testing before scaling up to treat the entire impacted location.

Specialty ISS equipment,
self-performance and technical expertise

Our specialty equipment is among the newest and best-maintained in the industry. We own drill rigs to perform deep soil mixing, as well as excavators for shallower solutions. Because we self-perform our work with our own equipment, we are able to deliver consistent, reliable results. ENTACT combines industry leading technical and field expertise, extensive equipment resources and in-house performance accountability.  

In addition to our specialty equipment, ENTACT owns and maintains over 300 pieces of yellow iron heavy equipment including excavators, loaders, articulated dump trucks, bulldozers, and other specialty pieces. To supplement this fleet, ENTACT owns and operates over 500 smaller pieces. ENTACT firmly believes properly maintained equipment matched to the project scope is critical to success. Our fleet of owned and long-term leased heavy and geotechnical construction equipment is supplemented with process system tools, technical support instrumentation, and transportation vehicles.

Scene of In-Situ Solidification/Stabilization In Progress

In-Situ Solidification/Stabilization Challenges.
ENTACT Solutions.

Disposal Services Site



ISS Method

Bucket mixing


87,000 cubic yards, up to 12 feet deep

ENTACT completed remediation activities at a petrochemical and industrial waste site, which included treating more than 11 million gallons of impacted water and performing ISS of 87,000 cubic yards of hydrocarbon and PCB-impacted sludges up to 12 feet deep. Additional services performed included managing stored liquids, demolishing tanks and other equipment, managing more than 500,000 cubic yards of impacted soils, and constructing a 33-acre capping system. In addition to managing waste, ENTACT also created a 12-acre waterfowl habitat lake borrow material from the on-site borrow area. 

Waste Oil Pits Site



ISS Method

Horizontal auger mixing


45,000 cubic yards

To restore a former waste oil pits site, ENTACT performed ISS activities on 45,000 cubic yards of acidic hydrocarbon sludge. Challenges included relocating half of a mile of an existing stream and excavating 10,000 cubic yards of impacted sediments from within a cypress swamp while preserving tree root structures. We also installed a perimeter slurry wall, constructed a capping system over the entire site and installed an extensive under-drain network to collect stormwater. 

Active Iron and Steel Manufacturing Facility



ISS Method

Bucket mixing


165,000 cubic yards

ENTACT completed corrective measures at this active manufacturing facility without hindering the plant’s daily operations. Using excavator bucket mixing, ENTACT Associates stabilized 165,000 cubic yards of impacted soil and consolidated more than 120,000 cubic yards of overburden soil. We also dewatered, in-situ stabilized, excavated and disposed of more than 80,000 cubic yards of impacted sludges and sediment off-site. Site restoration activities also included capping treated material, lining more than three acres of pond, and plugging and abandoning two groundwater monitoring wells before installing six new wells. 

Process Unit Proposed Location


Gulf Coast

ISS Method

Vertical auger mixing


86,000 cubic yards, from 22 to 24 feet deep

Subsurface soils consisted of saturated, soft and sandy clay on top of very soft clay. To strengthen this area, ENTACT performed ISS on approximately 86,000 cubic yards from 22 to 24 feet below ground surface. Using a combination of granulated ground blast furnace slag and Portland cement delivered by a vertical auger mixing rig, we achieved the necessary strength and permeability requirements to allow for the construction of the process unit.