Abstract: Reactive treatment cells (RTCs) are described in combination with sediment capping systems as a means for environmental remediation. RTCs include an impermeable housing defining an interior, a permeable ceiling and floor typically including filtration materials such as geotextiles, and at least one interior compartment for treatment reagents. One RTC includes a gabion-like cage structure retaining a geomembrane-supported geosynthetic clay liner (GM-GCL) housing, while a second embodiment includes a hard, cylindrical shell as a replaceable reagent cartridge. RTCs may be employed in initial capping system installations or retrofitted into existing capping systems. RTCs may include optional baffles, flow restrictors, floating discs, sensor probes, and two or more serial reagent zones or compartments.

Abstract: Composite particles of a hard core coated by a layer of hydratable, swellable clay such as bentonite are useful for constructing, modifying and/or supporting lifeline structure such as dams, berms and levees, and/or pipelines or conduits for oil, gas, sewage, water, or cables or wires for transmission of electrical power or data information. The method involves placing the composite particles in a location within, below, or about the lifeline structure, and hydrating them to cause them to swell and fill and seal the voids around the structure to form a resilient support having a high damping ratio and low hydraulic conductivity that is maintained after exposure to strain forces. The composite particles are advantageous in damping seismic waves and reducing the potential damage from an earthquake, explosion, tremor, fatigue loading, or similar seismic event.

Abstract: Composite particles contain a natural stone or aggregate core and a coating of two or more sorbent layers collectively containing at least two distinct kinds of sorbent materials effective for sorbing two distinct contaminants. One or both sorbent layers may be mixed with a water-absorbent, swellable clay that, upon contact with water, causes spalling or disintegration of the coating layer to release the sorptive material into a body of water such as a pond, ditch, stream, or riverbed. Additional swellable or protective layers may also be present. The composite particles are deployed into a pond, ditch, river, or streambed where the core of natural stone remains in the riverbed. The sorptive materials of the two different sorbent layers sorb and fix a wide range of contaminants, including both the heavy and light-weight hydrocarbons, from the water, and settle as a fine sediment. The sediment with sorbed contaminants is then removed by means such as hydraulic collectors or dredging.

Abstract: The invention relates to a low-permeability geotechnical barrier material including a blend of approximately equal parts of: aggregate particles, sand-size particles and manufactured composite particles that include a hydratable sealant material composed of naturally-occurring clay minerals and/or polymer-enhanced clay minerals, such that the actual percentage of clay mineral component is less than 10% by weight in the blended material. In a particular embodiment, the construction of a low-permeability geotechnical barrier using predominantly coarse grain materials by conventional compaction efforts is rarely attempted due to the difficulty of maintaining a uniform mix of well-graded sand and aggregate blends necessary to achieve low permeability. The regularly achievable permeability offered by this material blend when installed with specific proscribed techniques using conventional equipment can be 5×10?8 cm/sec or lower.

Abstract: Contaminated sediment is re-mediated using a self-regenerating reactive sedimentation capping system comprising a system of composite particles having a core and a coating. The coating of at least some particles further include a complexing or sorptive reactive material, such as activated carbon, appatite, a clay or organoclay, or a synthetic sorptive such as Sorbster™. The same or different particles contain a composition of dormant microbes capable of utilizing various contaminants as a food source. The same or other particles may also contain nutrients, micronutrients, vitamins, cofactors, buffers or other adjunctive compounds to sustain the microbes. The microbes feed on and degrade the contaminant compounds complexed, absorbed or adsorbed by the reactive material, thereby regenerating the reactive material for re-use.

Abstract: Composite particles contain a natural stone or aggregate core and a coating of two or more sorbent layers collectively containing at least two distinct kinds of sorbent materials effective for sorbing two distinct contaminants. One or both sorbent layers may be mixed with a water-absorbent, swellable clay that, upon contact with water, causes spalling or disintegration of the coating layer to release the sorptive material into a body of water such as a pond, ditch, stream, or riverbed. Additional swellable or protective layers may also be present. The composite particles are deployed into a pond, ditch, river, or streambed where the core of natural stone remains in the riverbed. The sorptive materials of the two different sorbent layers sorb and fix a wide range of contaminants, including both the heavy and light-weight hydrocarbons, from the water, and settle as a fine sediment. The sediment with sorbed contaminants is then removed by means such as hydraulic collectors or dredging.

Abstract: The invention relates to a low-permeability geotechnical barrier material including a blend of approximately equal parts of: aggregate particles, sand-size particles and manufactured composite particles that include a hydratable sealant material composed of naturally-occurring clay minerals and/or polymer-enhanced clay minerals, such that the actual percentage of clay mineral component is less than 10% by weight in the blended material. In a particular embodiment, the construction of a low-permeability geotechnical barrier using predominantly coarse grain materials by conventional compaction efforts is rarely attempted due to the difficulty of maintaining a uniform mix of well-graded sand and aggregate blends necessary to achieve low permeability. The regularly achievable permeability offered by this material blend when installed with specific proscribed techniques using conventional equipment can be 5×10?8 cm/sec or lower.

Abstract: Composite particles of a hard core coated by a layer of hydratable, swellable clay such as bentonite are useful for constructing, modifying and/or supporting lifeline structure such as dams, berms and levees, and/or pipelines or conduits for oil, gas, sewage, water, or cables or wires for transmission of electrical power or data information. The method involves placing the composite particles in a location within, below, or about the lifeline structure, and hydrating them to cause them to swell and fill and seal the voids around the structure to form a resilient support having a high damping ratio and low hydraulic conductivity that is maintained after exposure to strain forces. The composite particles are advantageous in damping seismic waves and reducing the potential damage from an earthquake, explosion, tremor, fatigue loading, or similar seismic event.

Abstract: Composite particles are used in combination with ore particles in an ore-refining or purification process, such as in a steel- or iron-making process. The composite particles comprise a core, which may be an aggregate of limestone, dolomite, or another ore particle. The core is surrounded by a coating layer of a metal dust and a binder. The metal dust may be iron oxide dust, which, along with limestone, is prevalent in the iron smelting process anyway. In this way, the composite particles help to recycle otherwise wasted and hazardous iron dust. The binder may be mineral clay such as bentonite, montmorillonite or kaolinite, and may comprise about 2-10% by weight of the particle.

Abstract: Contaminated sediment is re-mediated using a self-regenerating reactive sedimentation capping system comprising a system of composite particles having a core and a coating. The coating of at least some particles further include a complexing or sorptive reactive material, such as activated carbon, appatite, a clay or organoclay, or a synthetic sorptive such as Sorbster™. The same or different particles contain a composition of dormant microbes capable of utilizing various contaminants as a food source. The same or other particles may also contain nutrients, micronutrients, vitamins, cofactors, buffers or other adjunctive compounds to sustain the microbes. The microbes feed on and degrade the contaminant compounds complexed, absorbed or adsorbed by the reactive material, thereby regenerating the reactive material for re-use.

Abstract: Contaminated sediment is remediated using a sedimentation capping system comprising composite particles having a core and a coating containing a statin composition. The statins are useful for inhibiting the growth of methanogens, known anaerobes that produce methane from organic materials found in sediments. The reduction in methane production avoids several problems in capping systems, including reduced ebullition that may breach the barrier cap, reduced mobilization and bioavailability of methylated toxins to aquatic life above the cap.

Abstract: Reactive treatment cells (RTCs) are described in combination with sediment capping systems as a means for environmental remediation. RTCs include an impermeable housing defining an interior, a permeable ceiling and floor typically including filtration materials such as geotextiles, and at least one interior compartment for treatment reagents. One RTC includes a gabion-like cage structure retaining a geomembrane-supported geosynthetic clay liner (GM-GCL) housing, while a second embodiment includes a hard, cylindrical shell as a replaceable reagent cartridge. RTCs may be employed in initial capping system installations or retrofitted into existing capping systems. RTCs may include optional baffles, flow restrictors, floating discs, sensor probes, and two or more serial reagent zones or compartments.

Abstract: A landfill includes a layer of solid waste and a barrier layer provided on top of the layer of solid waste. The barrier layer is formed from a plurality of manufactured composite particles that include a plurality of solid pieces having a hydratable material applied thereto. A flexible membrane layer is provided on top of the layer of barrier layer. A method of producing such a landfill is also disclosed.

Abstract: Fiber-containing composite particles and fiber-reinforced barrier matrix compositions made from them are disclosed. The composite particles include a core, a hydratable clay mineral layer, an optional protective coating, and a reinforcing fiber. The fiber may be present in any or all of several locations: adhered to the core, dispersed in the hydratable layer or in the protective coating. Upon hydration, the hydratable clay mineral layer swells and forms a matrix that cohesively holds the fibers and the core in a fiber-reinforced barrier matrix composition.

Abstract: The invention relates to a barrier cap material including a blend of: a plurality of aggregate particles, and a plurality of manufactured composite particles including a hydratable sealant material. In a particular embodiment, the segregation of a blend of aggregate particles and composite particles, when dropped through a water column can be controlled by varying blends of aggregate and composite particles. In another embodiment, the permeability of the barrier cap material, when hydrated on a surface, can be controlled from 1×10?3 cm/sec to 1×10?8 cm/sec by varying blends of aggregate and composite particles.

Abstract: A method of treating a metal-contaminated sediment includes capping the sediment with a capping product containing sulfur and at least one component selected from the group consisting of clays, clay-sized materials, bulking agents, sand, sand-sized materials, aggregate, and binding agents. A capping product includes a plurality of manufactured composite particles, each composite particle comprising a relatively dense core and a sealant layer at least partially encapsulating the core, the sealant layer including sulfur and at least one of the above components.

Abstract: A sprayable composition and a method of protecting material with the composition is disclosed. The composition comprises a bulking/setting material, a water soluble polymer and water to provide a cover layer which, after spraying, is tough, flexible and water-repellent. Other materials such as clay, fibrous material, a foam producing agent and a hardening retarder can be included in the composition. The composition is effective as a cover layer over material such as soil, refuse at a dump site, stockpiled material, a temporary cover for remediation sites, or tire piles.

Abstract: In a method of creating a seal in a subsurface environment, a plurality of manufactured composite particles are placed in the subsurface environment, the composite particles including a sealant material. The sealant material is hydrated to create a cohesive seal. In a method of controlling erosion of a periodically or continuously inundated surface, a plurality of manufactured composite particles are placed around erosion-control objects. The composite particles include a sealant material which is a cohesive, low-permeability material when hydrated. The sealant material physically stabilizes the erosion-control objects on the surface. The invention also relates to compositions and properties of the composite particles.

Abstract: A remediation technology that can effect an isolating or sealing barrier that treats or facilitates treatment of contaminated surfaces.

Abstract: A method of treating a contaminated material in which a low-permeability barrier is formed over the contaminated material, thereby creating a substantially hydraulically closed system. The material beneath the barrier is treated by at least one of delivering a substance to treat the contamination and removing flowable material from beneath the barrier. The invention also relates to compositions and properties of composite particles suitable for the treatment method, additional methods of implementing the composite particles, and methods of applying the composite particles.