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Auger Cast Piles - Auger Cast Piles are installed by rotating a continuously flighted hollow shaft auger into the soil to a specified depth. High strength cement grout is pumped under pressure through the hollow shaft as the auger is slowly withdrawn. The resulting grout column hardens and forms an auger cast pile. Reinforcing, when required, can be installed while the cement grout is still fluid, or in the case of full length single reinforcing bars, through the hollow shaft of the auger prior to the withdrawal and grouting process.

Biopolymer Trenches - Biopolymer (BP) trenching is an innovative technique for installing permeable drainage trenches. BP trenches use synthetic biodegradable polymer water-based slurry to support the trench walls. This method provides several advantages over traditional construction techniques, particularly for deep applications that extend below the groundwater table. Additionally, the BP sluury stabilizes the excavation walls resulting in a safer project.

Deep Foundations - Deep foundations are literally braced (supported) column elements transmitting structure loads down to the subgrade supporting medium. A single drilled shaft or a group of driven piles is typically designed to support a column load. The number of driven piles in a group is determined by dividing the column load by the design load of a single pile.

Deep Soil Mixing - Deep Soil Mixing is a soil improvement technology used to construct cutoff or retaining walls and to treat soils, in-situ. This is accomplished with a series of overlapping stabilized soil columns (typically 36-inch diameter). The stabilized soil columns are formed by a series of mixing shafts (2 to 4), guided by a crane-supported set of leads. As the mixing shafts are advanced into the soil, (grout or slurry) is pumped through the hollow stem of the shaft and injected into the soil at the tip. The auger flights and mixing blades on the shafts blend the soil with the (grout or slurry) in pugmill fashion.

Diaphragm Walls - Diaphragm walls are commonly used in congested areas for retention systems and permanent foundation walls. They can be installed in close proximity to existing structures with minimal loss of support to existing foundations. In addition, construction dewatering is not required so there is no associated subsidence. Diaphragm walls have also been used as deep groundwater barriers through, and under, dams. In some applications, they are constructed from non-reinforced plastic concrete.

Groundwater Remediation - There are a variety of techniques used to remediate groundwater. Some of the more common techniques include: Groundwater Pump and Treat; Air Sparging; Vapor Extraction Systems; Drawdown Pumping; Surfactant Enhanced Recovery; Bioremediation using Oxygen Release Compound; and Bioremediation using Hydrogen Release Compound.

Jet Grouting - Jet grouting is a general term describing various construction techniques used for ground modification or ground improvement. Grouting contractors use ultra high-pressure fluids or binders that are injected into the soil at high veolocities. These binders break up the soil structure completely and mix the soil particles in-situ to create a homogeneous mass, which in turn solidifies. This ground modification / ground improvement plays an important role in the fields of foundation stability, particularly in the treatment of load bearing soils under new and existing buildings; in the in-depth impermeabilization of water bearing soils; in tunnel construction; and to mitigate the movement of impacted soils and groundwater.

Permeable Reactive Barriers - Permeable Reactive Barriers (PRBs) are often referred to as iron filing walls, reactive barriers, funnel and gate systems, or passive treatment walls. Regardless of the name, PRBs can provide cost-effective, long-term solutions for many groundwater contamination problems. They are constructed underground to intercept groundwater flows and to provide preferential flow paths through reactive materials. As groundwater moves through the reactive materials, contaminants are treated and transformed into harmless by-products.

Secant Piles - Secant pile walls are an innovative way to build retaining walls. They are formed by a series of interlocking drilled shafts and are used primarily where there is a high water table or unsuitable ground conditions. Secant pile walls are attractive near buildings, roads, and other sensitive structures because of the lack of noise and vibration during construction. Secant walls can be used to form a continuous watertight wall - an added benefit on environmental projects.

Sediment Caps - To effectively contain contaminants, sediment caps consisting of soil particles, sand and minerals can be placed over the contaminated layer to form a protective barrier.

Sheet Piling - Sheet piling consists of a series of panels with interlocking connections, driven into the ground with impact or vibratory hammers to form an impermeable barrier. Sheets can be made from a variety of materials such as steel, vinyl, plastic, wood, recast concrete and, fiberglass. Sheet piling has been a proved technology within the construction industry for years. The most recent addition was the vinyl sheets introduced in 1989. These vinyl sheets, with imperious sealants, have made this a very attractive alternative for the cutting-off or containing contaminated groundwater flow within the environmental industry.

Sludge Stabilization - Sludge Solidification / Sludge Stabilization reduces the mobility of hazardous substances and contaminants through both physical and chemical means. Unlike other remedial technologies, Solidification/stabilization seeks to trap or immobilize contaminants within their "host" medium (i.e., the soil, sand, and/or building materials that contain them), instead of removing them through chemical or physical treatment. Leachability testing is typically performed to measure the immobilization of the contaminants. Solidification/stabilization techniques can be used alone or combined with other treatment and disposal methods to yield a product or material suitable for land disposal or in other cases, that can be applied to beneficial use. These techniques have been used as both final and interim remedial measures.

Slurry Walls - Slurry wall construction is used to create non-structural barriers (Cutoff Walls, Slurry Trenches), which are constructed underground to impede groundwater flow. Slurry walls have been used for decades to provide cost-effective, long-term solutions for many groundwater control problems. Literally thousands of slurry walls / slurry trenches have been installed in the United States and their uses are increasing.

Soil Mixing - Soil mixing is a technique that utilizes the introduction of an engineered grout or reagent to modify the physical or chemical characteristics of soil without excavating. The technique has numerous civil and environmental applications and can use a wide range of mixing equipment.

Soil Modification - Soil modification is a broad term used to describe any technology or operation that changes the structural strength of the soil. Within the environmental and geotechnical industries, these technologies include jet grouting, soil mixing, soil solidification, and soil stabilization.