This page highlights Lang Tool Company’s approach to ISS/ISCO Implementation and the equipment that supports it. Our three mini presentations explain the process, show a real case study, and outline the tools used for consistent results.

ISS/ISCO Overview
  • ISS/ISCO Overview
  • ISS/ISCO (In-Situ Stabilization/In-Situ Chemical Oxidation) is a soil mixing procedure that uses Portland cement to activate sodium persulfate and is applied in one pass. The process has the added advantage of decreasing the hydraulic conductivity of the soil, and the treated soil is strong enough to allow construction to begin immediately after ISS/ISCO is completed.
  • Lang Tool Co. has performed many ISCO (In-Situ Chemical Oxidation) and ISCR (In-Situ Chemical Reduction) soil mixing projects using a variety of reagents. They were successful in that the sites met the cleanup criteria, but they all shared one feature. When ISCO was finished, the sites were so wet that they were unusable for a long period of time. The following examples showcase ISCO and ISCR projects which met cleanup criteria but faced the same challenge.
  • This project was conducted with Environmental Field Services in Ashippum, WI, using Daramend as the reagent. Completion of the project was delayed by months due to the difficulty in backfilling. Note that there was a layer of clean overburden that had to be stockpiled and later returned. This is commonly referred to as double handling.
  • This project was conducted with ISOTEC in Conway, NH, using MFR. As is often the case with chlorinated solvents, there were several feet of clean soil above the contamination. The clean soil was excavated in a row along the north side of the treatment area. As Lang Tool Co. moved down the row, the adjacent row was excavated, leaving a small dike between the 1st and 2nd rows, as can be seen in the picture at left. The work continued across the site in this manner. The excavated soil was stockpiled to be returned when the site dried.
  • Lang Tool Co. waited for two days for the last round of test results before demobilizing. The test results came back showing that the ISCO process had met the cleanup criteria. However, the contractor that was to perform the backfilling had a difficult time, and in the end the treatment area had to be stabilized before any backfilling could be accomplished.
  • This ISCO project was conducted with Viasant using Klozur. Viasant’s plan was to stabilize the treatment area with dry cement mixed with an excavator, but this approach did not work. The cement was delivered in super sacks, and Viasant attempted to dump the bags on the surface and mix it in. Instead, the cement displaced the wet soil and sank to the bottom. As a result, stabilizing the site and finishing the grading were not completed until the following year.
  • This project was conducted with Fehr Graham at the Danfoss factory in Ames, Iowa. As shown, the ISCO treatment resulted in the site being extremely wet when ISCO was completed.
  • The operator of this piece of equipment found out how soft the site was. The engineer sent this photo three months after Lang Tool Co. completed the ISCO soil mixing. It’s fortunate that the operator made it out of the machine, as he had to exit through the front.
  • All four of these projects met the cleanup criteria but were not in a usable condition for a long period after ISCO was performed. ISS/ISCO solves this problem in a cost-effective manner while aiding in the remediation, as it slows the hydraulic conductivity through the site soils. The following example showcase an ISS/ISCO project which met cleanup criteria and solved the common stability issues found when conducting ISCO or ISCR projects alone.
  • The Philadelphia ISS/ISCO project involved mixing 4,500 cubic yards of soil and was completed in just seven working days. LTC’s approach uses a persulfate solution mixed in tanks on the ISCO Mixing Plant, which is then pumped in controlled quantities to the ISS Mixing Plant and blended with cement. This combined mixture is delivered to the LTC Dual Axis Blender, which incorporates it into the contaminated soil — completing ISS and ISCO in a single pass.
  • This is the cell layout for the ISS/ISCO project. The property belonged to Dow but was leased to Carvana. The entire site was a large paved parking lot. The elevations listed are in mean sea level. Note that the cell designation uses East columns and South rows.
  • The soil above the water table was determined to be clean. ISS/ISCO was required from 3.5 feet MSL to the various elevations shown. To avoid the double handling associated with stockpiling the clean soil, Lang Tool Co. excavated the clean soil from the S9 row and placed it immediately adjacent to the row. Treatment on the S9 row was then started, and the next morning clean soil was excavated from the S8 row and placed on the treated soil in the S9 row. The work continued in this manner until ISS/ISCO was completed across the entire site.
  • Upon removing the overburden, the treatment interval was exposed and found to be fully saturated. Under a traditional ISCO‑only approach, these conditions would have left the site too wet to backfill or work for an extended period. That was not the case with ISS/ISCO.
  • Just one day after ISS/ISCO was completed, the site was dry, stable, and ready for follow‑up construction activities. By eliminating long drying periods and the need for stockpiling, ISS/ISCO reduces costs and accelerates the reuse of the property.
  • ISS/ISCO eliminates the double handling associated with stockpiling and renders the site usable immediately after soil mixing is completed.

Learn how Lang Tool Co.’s integrated soil‑mixing method improves the results of traditional ISCO. This overview explains the science behind the process and shows how combining ISS and ISCO strengthens the soil and reduces contaminants. In addition, it highlights the benefits and real‑world results of using both methods together.

📄 Download ISS/ISCO Overview PDF
ISS/ISCO Case Study
  • ISS/ISCO Case Study
  • Lang Tool Co. treated 12,400 cubic yards at a former dry-cleaning site in Lansing, MI using Klozur persulfate activated with Portland cement and a small amount of NaOH. The ISS/ISCO process was selected to meet cleanup goals while stabilizing the soil for immediate reuse. This project demonstrates how integrated mixing streamlines remediation and site restoration.
  • The contaminated area was the entire property, bordered by streets and residential properties.
  • Initially, 3 feet of low‑level contaminated soil was excavated and hauled. The highly contaminated soil extended 19 feet below the initial excavation, requiring that the ISS/ISCO work be performed in two tiers. It was anticipated that swell would increase the elevation by around 25%, which proved to be accurate.
  • The E12 column, which is on the east end of the site, was excavated to 846 feet, as shown on the left. This soil was leveled over the eastern half of the site. ISS/ISCO began in the E12 column. On the morning of the second day, soil excavated from the E11 column was deposited on the previously stabilized E12 column, as shown at right. Soil mixing and excavation proceeded in this manner from east to west until the E7 column lower tier was completed.
  • At that point, ISS/ISCO of the upper tier commenced in column E12, as shown in the right illustration, and proceeded east to west. The entire site required treatment, so the reagent plants were set up first on the west side and then moved to the east side when ISS/ISCO was completed on the eastern half.
  • As shown here, ISS/ISCO eliminates double handling. While the Dual Axis Blender is mixing in the E11 column, the excavator is digging the E10 column to 846 feet. The soil was then deposited on the northern end of the E11 column that was treated the day before. The stabilized soil in the E11 column can be seen at the bottom left of the photo.
  • Pictured here is the Dual Axis Blender mixing in the E10 column that was being excavated in the previous slide. The excavated upper‑level soil has been leveled over the E12 and E11 columns on the left side of the picture. Note that there was no stockpiling of excavated soil. This is true on projects such as this that require an upper level of treatment and on projects that have a clean upper layer that doesn’t require ISS/ISCO.
  • The berm on the left is soil scraped from the previously mixed column to the east of the column being treated. The ISS and ISCO reagent delivery plants are set up on the western side of the treatment area. Once both tiers on the east side were completed, the plants were moved to the east side so ISS/ISCO could be performed on the west side.
  • After several columns in the top tier had received ISS/ISCO on the east side of the treatment area, the soil resembled dry, crumbly clay—ideal for grading and backfilling.
  • With the top tier of the eastern side of the project completed, ISS/ISCO’s efficiency kept the project moving without downtime.
  • When the lower and upper tiers were completed on the east side, the reagent plants were moved to the east side, and work on the west side was done in the same manner. In the photo, soil mixing and excavation are being done in conjunction as described earlier.
  • The Dual Axis Blender commenced mixing in the last column of the lower tier on the west side. The ISS & ISCO reagent plants are on the extreme east side of the site.
  • In total, 12,353 cubic yards were treated in 28 working days using 816 tons of Portland cement, 440,800 pounds of Klozur persulfate, and 15,080 pounds of NaOH. The final cell marked the end of a clean, efficient remediation. ISS/ISCO delivered both chemical performance and structural stability.
  • ISS/ISCO was completed late Thursday afternoon. Friday the equipment was cleaned up and some of it was demobilized. Monday the rest of the ISS/ISCO equipment was demobilized. Tuesday the excavator pulled in the outside berms and the dozer leveled the site. At noon the site was usable.
  • This photo was taken on December 10th, about a month after Lang Tool Co. left the site. A grading contractor imported topsoil and completed the finish grading, and the site security fence was removed. The site was ready for development. ISS/ISCO made it possible to meet cleanup goals and prepare the land for future use—all in one streamlined process. This is remediation built for real-world timelines.

Explore a full ISS/ISCO implementation at a former dry‑cleaning site in Lansing, Michigan. This case study follows the project from excavation through final grading. It also shows how Lang Tool Co. delivered consistent mixing, strong process control, and reliable field results.

📄 Download ISS/ISCO Case Study PDF
ISS/ISCO Equipment & Process
  • ISS/ISCO Equipment & Process Control
  • The Dual Axis Blender is the primary mixing tool. It rotates on a vertical axis and uses counter‑rotating drums on a horizontal axis to generate maximum mixing energy at the reagent injection point. The carrier has been extensively modified, including replacing the original 200 hp engine with a 480 hp engine and adding hydraulic pumps to power the blender functions. This is the secret of successful soil mixing—a lot of power.
  • Real-time mixing footage showcases the power and extreme mixing energy generated by the Dual Axis Blender. No single-axis blender, whether it’s a vertical or horizontal axis, can match the mixing energy of the DAB.
  • Additional footage of the Dual Axis Blender highlights its high mixing energy and effectiveness on the Horseburgh & Scott site in Cleveland.
  • ISCO Plant consists of: Truck Crane to load bulk bags of Klozur; Dry Bin with scales to meter Klozur into mix tanks; Mix Truck with platform scales & diaphragm pump to meter NaOH into mix tanks; Pumps & controls to meter & pump reagent solution to ISS plant. The LTC ISCO Plant mixes and pumps reagent solution to the LTC ISS Plant. The operator enters the quantities of water, Klozur, and NaOH for each cell. When these quantities are reached, the system shuts the transfer off, which allows the plant operator to concentrate on the delivery of reagent to the blender from one tank while the other tank is filling.
  • ISS Plant includes: 800 ft³ silo for bulk cement storage; 270 ft³ mix truck that augers a controlled quantity of dry cement & ISCO reagent solution to a mixing auger that produces a slurry; Piston grout pump that delivers the slurry to the blender. The LTC ISS Plant is programmable, similar to the ISCO Plant. The cement quantity and water ratio are entered, and the system automatically stops cement delivery when the set amount is reached. The operator can adjust the delivery rate to match the blender’s mixing progress.
  • The Dual Axis Blender is equipped with GPS. The operator sees the cell layout, the blender, and the blender head. The ‘Dist’ is the distance to the target elevation, and that, along with the cross‑sectional view on the right, shows the mixing progress. The screen the operator sees is broadcast to both mixing plants so the operators know for certain which cell is being mixed and can match the reagent delivery to the mixing progress.
  • The quantity and rate of delivery can be precisely controlled. Delivery information can be downloaded from the plant computers. The spreadsheet was downloaded from the ISS Plant onboard computer.
  • Pictured at left are the ISS and ISCO plants set up on an ISS/ISCO project in Columbia City, Indiana. The image at right shows the Dual Axis Blender mixing while the excavator removes the clean overburden on the same project.
  • With integrated ISS/ISCO systems, advanced equipment, and precise process control, Lang Tool Co. provides remediation solutions that meet real‑world timelines and deliver lasting results.

See how Lang Tool Co.’s Dual Axis Blender and reagent plants support precise ISS/ISCO implementation. These custom‑built systems provide strong control, consistent mixing, and real‑time coordination. In addition, GPS integration and data logging help teams track progress and maintain quality throughout the project.

📄 Download ISS/ISCO Equipment & Process Control PDF
Download Full ISS/ISCO Implementation PowerPoint Presentation

Download our full ISS/ISCO Implementation Presentation. It combines all three mini presentations and explains the overview, the case study, and the equipment used in the process.

ISS/ISCO Implementation FAQ

In Situ Stabilization/Solidification (ISS) and In Situ Chemical Oxidation (ISCO) are complementary remediation methods used to treat contaminated soil. ISS strengthens the soil by mixing in binding agents. ISCO, on the other hand, uses chemical oxidants to break down contaminants. The combined procedure uses Portland cement to activate sodium persulfate and is applied in one pass. As a result, the process decreases the hydraulic conductivity of the soil and improves overall site stability.

The combined ISS/ISCO approach is used when a site needs both soil stabilization and contaminant treatment. This method is helpful when a project requires stronger ground support while also reducing contaminants. In addition, the treated soil becomes strong enough to allow construction to begin on development sites immediately after ISS/ISCO is completed. Because of these benefits, ISS/ISCO is often selected for industrial sites, brownfields, and redevelopment projects that need predictable, long‑term results.

Lang Tool Company has decades of experience supporting ISS/ISCO remediation. Our equipment delivers consistent reagent distribution and unmatched mixing performance. In addition, our process control methods help ensure predictable results across a wide range of soil conditions. Because of this expertise, project teams can depend on our tools and support throughout the entire implementation process.