We are experts in environmental remediation solutions for contaminated sites.
At Forgen, we specialize in environmental remediation and specialty civil construction for various sites, including former manufactured gas plants (MGP), coal power plants, legacy mines, superfund sites, hazardous landfills, and other legacy industrial sites such as pulp and paper, chemical, and wood-treating facilities.
Our expertise extends to geotechnical construction, involving innovative solutions for stabilizing and improving soil and subsurface conditions essential for environmental and structural integrity. We employ solidification and stabilization (S/S) technologies to treat contaminated waste. Solidification encapsulates contaminants in a solid mass, reducing porosity and mobility, while stabilization uses reagents to reduce the solubility and toxicity of contaminants or immobilize the contaminants. Typically, both methods are discussed as a single technology and implemented together. By combining these techniques, we effectively reduce the leaching and movement of pollutants, preventing them from reaching groundwater or surface water bodies.
Our capabilities include the physical removal, transport, and proper disposal of contaminated soil, sediment, and surface water, as well as capping, solidification, and stabilization of contaminants in place.
We are also highly experienced in constructing subsurface barrier walls, including slurry walls, permeable reactive barriers, and biopolymer collection trenches. These hydraulic containment solutions further enhance our remediation efforts by providing effective barriers to the migration of contaminants.
Remediation & Stabilization Capabilities
Featured Project Experience
Forgen constructs soil/drainage covers and low-to-no permeability caps to isolate pollutants and prevent them from migrating from contaminated sites. Capping is an economical alternative to removing or stabilizing contaminated material on remediation sites and effectively prevents pollutants from entering groundwater or air. Depending on the cap’s purpose, we install these caps using compacted clay, geomembrane, geosynthetic clay, geocomposite, and geotextile layers.
For landfill and contaminated site capping projects, Forgen uses materials such as high-density polyethylene (HDPE) geomembrane liners, polyvinyl chloride (PVC) sheeting, and low linear density polyethylene (LLDPE) geomembrane liners. Our covers include soil and gravel layers for erosion control, vegetation support, drainage, and full barrier protection to halt water or gas vapors. We also construct evapotranspirative (ET) covers and other combinations of topsoil, gravel, cobbles, sand, geonets, and geocomposites.
Featured Project Experience
One cost-effective way Forgen implements ISS (In Situ Stabilization) in shallow soils and impacted media at depths ranging from 0 to 30 feet bgs is using hydraulic excavators with standard buckets or specialty mixing implements.
The excavator loosens and turns the soil within a defined horizontal and vertical area while introducing dry or regents mixed in slurry form directly into the excavation or through an injection nozzle integrated into the tool. The target media is then turned and mixed with the reagent to ensure consistent dispersion and achieve the desired consistency of the overall treated soil mass. As work progresses, we collect and analyze samples of the mixed media and reagent for specific parameters to achieve the desired performance results.
Featured Project Experience
Deep soil mixing (DSM) is an in-situ soil treatment technology that modifies the engineering properties of existing soil in well-defined zones such as columns, panels, or blocks. By designing the engineering properties and treatment patterns, DSM constructs subsurface soil-cement structures for various environmental remediation applications and civil engineering construction.
In DSM or ISS applications, we use large-diameter single-auger mixing, using an excavator mounted drill rig or crane-mounted turntable that rotates a mixing auger system (Kelly bar and auger) to drill into the affected soil. This method uniformly mixes the soil with cementitious-based grout or other additives. The FORGEN’s drill rigs typically rotate 4 to 12-foot-diameter auger to treat soil, sludge, and groundwater to depths of up to 100 feet. We inject liquid reagents, reagent grout, or other treatment media through the auger, which has injection ports on the auger flights. As the auger rotates through the soil, it mixes the injected media with the soil, creating an in-situ column of treated soil and groundwater upon completion.
Featured Project Experience
The ex-situ solidification/stabilization process is a remediation technique that traps contaminants within soils to limit their migration. This process involves removing the material from its original location for treatment. Ex-situ treatment typically uses conventional equipment and pugmills to mix large volumes of material into a uniform mixture for stabilization. The process includes excavating the contaminated material, adding a stabilizing agent, mixing, and then allowing it to settle for setting, curing, and hardening. The treated material can then be transported off-site for disposal or used on-site for beneficial reuse.
We utilize the ex-situ solidification/stabilization process to manage and remediate contaminated soils effectively. By removing contaminated material from its original location, we use conventional equipment and pugmills to achieve a uniform mixture of large volumes of soil. After excavating the contaminated soil, we add stabilizers and binding agents such as gypsum, lime, bentonite clay, Portland cement, and various additives like pozzolans, fly ash, sulfur, and blast furnace slag to the soil. Polymers, organic materials (such as biosolids, manure, and compost), and various minerals are also incorporated as admixtures.
Our stabilization method transforms the chemical properties of the contaminants, reducing their solubility in water, mobility, and toxicity. This technology is particularly effective for treating solid-contaminated matrices like soils, sludges, and sediments and is more easily implemented in silty, sandy, or gravelly soils compared to high-clay-content soils. This ensures a more effective and uniform mixture, facilitating easier handling and application of the treated material.
Featured Project Experience
Pugmills are twin shaft mixing systems designed with two horizontal mixing shafts equipped with synchronized mixing arms and adjustable paddle tips. These paddle tips accelerate the aggregates being mixed, creating intensive relative movements that result in a homogenous mixture within a short retention time of 8-10 seconds. There are two types of pugmill mixing: continuous and batch. In continuous pugmill mixing, reagents and waste materials are fed into the mixer in correct proportions during operation, continuously entering and exiting the mixing chamber. In batch pugmill mixing, reagents and waste materials are added in a predefined sequence, mixed, and then discharged before the next batch begins.
We employ pugmills to achieve efficient mixing of materials for various projects. Using twin shaft pugmill systems with synchronized mixing arms and adjustable paddle tips, we ensure a homogenous mixture within a short retention time. We apply both continuous and batch pugmill mixing methods depending on project requirements. This versatility in mixing techniques enables us to handle a wide range of materials and achieve consistent, high-quality results for their clients.
Forgen uses our fleet of excavators, including long-reach booms and sticks, to mechanically remove contaminated sediments from the shore or barges in the waterway. We dewater the removed sediments to pass a paint filter test before hauling them to an approved landfill for disposal. We treat water collected during removal and dewatering onsite and discharge it as permitted or ship it offsite for appropriate disposal. When necessary, we use environmental clamshell buckets to minimize resuspension and release of residual material.
Featured Project Experience
Environmental remediation and landfill construction projects often require stringent emissions controls to manage odors and volatile organic compounds (VOCs) such as toluene and benzene. Effective management involves using a variety of environmentally safe products and methods to protect workers, neighboring residents, and groundwater. Techniques include using foams and odor neutralizers such as misting or vapor systems, and fully enclosed tents with air treatment systems.
We apply stringent emissions controls on its environmental remediation and landfill construction projects to manage odors and volatile organic compounds (VOCs) like toluene and benzene. We use environmentally safe products and methods to ensure the protection of workers, neighboring residents, and groundwater. The company employs foams and odor neutralizers, including misting or vapor systems, and uses fully enclosed tents with air treatment systems. We have successfully implemented these techniques on projects ranging from manufactured gas plant (MGP) sites and legacy chemical plants to wood treating facilities, demonstrating its capability to handle diverse and challenging environments.
Featured Project Experience
Alternative Delivery
We specialize in delivering projects through alternative contracting methods, aiming to improve quality, reduce costs, enhance efficiency, and manage risks.
Our expertise in heavy civil, geotechnical construction, and environmental remediation allows us to provide innovative solutions with agility. Early stakeholder engagement ensures alignment of project goals, fostering transparency and accountability. By combining technical expertise with innovative problem-solving and strong client communication, we tailor our services to meet each project’s unique challenges, ensuring successful outcomes.
