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RECON is acknowledged as an industry leader in both the environmental and geotechnical markets. This level of success is the result of a long-term corporate strategy that fosters controlled growth and consistent profitability by focusing resources in three primary market areas:
Within each of these three markets, RECON offers a range of services and capabilities, ensuring that the optimum technical solution is available to our clients for virtually any environmental or geotechnical problem.
At RECON we recognize, however, that meeting the needs of our clients involves more than just providing a technically effective solution. It also means providing that solution safely and economically. Over the years, we have developed innovative technologies, management methods, contracting options and equipment to ensure the highest level of client satisfaction - in product quality, in onsite safety and in project costs.
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ENVIRONMENTAL REMEDIATION
RECON´s approach to environmental remediation is governed by the medium contaminated and by the nature of the contaminant itself. RECON´s in-depth experience with a variety of chemical, physical and biological remediation methods ensures that, regardless of the problem, the right solution is always available, be it for groundwater, soil, sludge, or structures.
Groundwater Remediation
RECON constructed its first groundwater remediation system in 1990, and since that time has continued to lead the industry in the construction of:
- Cut-Off Walls,
- Interception and Recovery Trenches, and
- Reactive Barrier Walls.
RECON´s groundwater cut-off capability includes:
- Soil/Bentonite Slurry Trenches,
- Cement/Bentonite Slurry Walls,
- Cement/Soil/Bentonite Slurry Walls,
- Attapulgite/Soil Slurry Trenches,
- Sheet Pile Cut-Off Walls
- Jet Grout Curtains,
- Secant Pile Cut-Off Walls,
- Impermix Slurry Walls, and
- Ground Freezing.
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RECON has constructed:
- The largest attapulgite/soil slurry trench in the world.
- The deepest sheet pile cut-off wall ever constructed with single sheets in the US.
- Excavated one of the deepest slurry walls with a hydraulic excavator.
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To complement its cut-off capability, RECON´s groundwater control services also include the active and passive treatment of contaminants.
Recovery Trench Installation is used to remove contaminated groundwater. RECON constructed its first recovery trench in 1991. Since that time, we have constructed more than 50 recovery trenches and reactive barrier walls using the following construction methods:
- Biopolymer Slurry
- One Pass Trench
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Reactive Barrier (Passive Treatment) Walls are used to permit groundwater flow through specific treatment media. Contaminants in the groundwater react with the installed treatment medium and are either degraded, precipitated or absorbed in situ, depending on the type of contaminant and treatment medium. RECON has used mushroom compost and iron filings to construct these barrier walls.
Soil
Soil is arguably the most challenging medium to remediate. RECON has pioneered many technologies, including thermal desorption, chemical oxidation and phosphate stabilization.
Remediation technologies for contaminated soils vary with the type of contaminant, the depth of the contaminated strata, and the soil type. However, the soil remediation technologies that RECON frequently uses to solve soil contamination problems can be divided into four main categories:
- Stabilization
- Chemical Oxidation
- Bioremediation
- Thermal Desorption
For soil stabilization or chemical oxidation, the following reagents are typically used:
Stabilization
- Triple Super Phosphate
- Impermix Grout
- Cement Based Grouts
- Chemical Grouts
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Chemical Oxidation
- Potassium Permanganate
- Hydrogen Peroxide
- Sodium Percarbonate
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Each soil remediation technique requires a mechanical mechanism to complete the treatment. To this end, RECON has developed the following specialized equipment:
- Deep Mixer (3-ft diameter three-auger)
- Shallow Mixer (8-ft diameter single flight auger)
- Surface Mixer (SS250 with injectors)
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- Ex-situ Mixer (windrow turner)
- Jet Grouting
- Ex-situ Mixer (pugmill)
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RECON´s experience with bioremediation includes the use of windrow composting, landfarming, bioheap extraction, and bioventing.
Sludge
The treatment of sludge can be accomplished using the same mixing mechanisms as those outlined above for soil treatment, with the addition of straightforward track excavator mixing. During the mixing operation, biological, chemical, or stabilizing reagents are introduced to treat or stabilize the sludge. Stabilizing reagents are most commonly used because of the added benefit of solidification. RECON´s sludge stabilization programs include the use of the following agents:
- Fly Ash
- Fluidized Bed Ash
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- Cement/Cement Kiln Dust
- Lime/Lime Kiln Dust
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Structures
As industrial and commercial manufacturing facilities built in the first half of the twentieth century become unproductive or obsolete, they are being demolished and replaced. Many of these facilities are contaminated with hazardous chemicals, requiring decontamination and decommissioning outside the scope of most commercial demolition contractors.
RECON project teams have the Occupational Health and Safety education and training, and the experience, to safely handle all types of hazardous decontamination and decommissioning. We have assisted owners with "Asset Recovery" from many facilities. In some cases this involves decontamination and decommissioning. In other cases, it involves decontamination and disassembly. RECON has demolished entire plants, multi-unit systems within plants, and individual components within
a system.
CELL AND CAP CONSTRUCTION
Risk based closures have increased the popularity of the onsite containment of contaminated material. This is typically accomplished by landfill cell and cap construction, generally consisting of earth moving and liner placement.
RECON has the physical resources and experienced site personnel to construct or close landfills of any size. These resources include over 100 pieces of owned heavy equipment excavators, dozers, compactors, off-road dump trucks, and scrapers and over 75 operators and superintendents skilled in cell and cap construction.
RECON has the expertise to meet any requirement for liner placement, including native clay, GCL, HDPE, LLDPE, PVC, geotextile, drainage sand, and geocomposites. In many cases, the cap or cell is a combination of several materials.
GEOTECHNICAL CONSTRUCTION
In the environmental construction market, meeting the project specifications typically involves modifying the physical properties of the soil. In many instances, this is also true of the geotechnical construction market. Techniques and equipment used for environmental work can therefore often be applied to solve geotechnical problems. Over the years, RECON has drawn on its environmental expertise to serve the geotechnical community, and has emerged as a leader in:
Retention Systems
RECON offers the following services for support of excavation and/or structural underpinning:
The product may be temporary, for the life of the construction project, or incorporated as a permanent part of the resulting structure. For diaphragm walls and secant pile walls in particular, incorporating the earth retention system into the design can realize considerable savings in time and costs for the overall project.
Soil Modification/Stabilization
In situ soil modification/stabilization techniques improve the bearing capacity of the soil to allow economical shallow foundation construction. RECON´s ground improvement services include:
Soil mixing uses a Single Auger Mixing (SAM) tool to treat the soil in-situ. SAM utilizes a crane mounted "turntable" to rotate a specially designed mixing tool. Reagent grout is pumped through the mixing tool, as it is rotated and advanced into the waste. The results is uniform, treated columns. Individual columns are overlapped to insure treatment of the entire soil mass.
Jet grouting is a replacement/mixing technology where a high-pressure "jet" of grout is used to erode and mix in-situ soil to create a blended mass of grout and soil with improved engineering properties, such as reduced permeability, and increased strength. This technology is effective in a range of soils from gravel to clay.
RECON has the equipment and experienced personnel to perform jet grouting and soil mixing technologies. The equipment includes a Casagrade drill rig capable of completing 60-foot single stroke jet grouted column and a Augercast Pile Rig capable of handling 8-foot diameter augers for deep soil mixing operations. Our in-house geotechnical managers all have at least 25 years experience in these and other geotechnical technologies.
Groundwater Control
With temporary or permanent groundwater control a consideration on many geotechnical construction projects, RECON offers the following services:
- Slurry cut-off walls and trenches
- Ground Freezing
- Deep Soil Mixing
- Dewatering
- One-Pass Trenching
For all of the above technologies, RECON provides budgetary estimates and constructability reviews. This unique service allows engineers and consultants to evaluate construction considerations before the project is presented to the client or released for bid.
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