Sediment remediation method

Sediment remediation methods can be subdivided according to the mode of handling (e.g., in-place or excavation), or to the technologies used (containment or treatment). Important containment techniques include capping in situ and confined disposal. Biological processes may be applied with in-place treatment. Excavated sediments - apart from physical separation -can be treated to immobilize pollutants, most of which are metals (Table 8.2). 

Similar to soil remediation, in situ control and excavation-and-treat methods can be applied to sediment remediation. 

Soil and sediments major contaminants - behaviour, fate and transport chemical and biological remediation methods heavy metals, lead, arsenic (two lectures)... 

Research on methods for estimation of spatial variability of deposition and resuspension in large, complex sites, and how to use that information for planning sediment remediation. 

With the recent Increase In activity at hazardous waste sites where cleanup and remedial action are underway, there has emerged a need for rapid analytical methods for assessing contamination in water, sediment, and soil. Of special Interest, because of widespread use and disposal. Is the group of materials known as PCB s (polychlorinated biphenyls). 

In situ methods have potential use as an interim or emergency measure until dredging can be undertaken or as a primary remedial action where it is determined to be more cost-effective than removal. The biggest advantages are that they are much less costly than dredging, eliminate the need for dredged material management, and minimize the resuspension of contained sediments.15... 

The method or methods employed to remediate an aquifer vary, depending on the type, degree, and extent of contamination. Where pollution is shallow and dispersed over a small area, the sediments can sometimes be dug up and transported to a landfill designed especially to isolate the contaminants. Permeable reaction barriers can be installed to intercept a contaminant plume and strip pollutants from it, if the plume is shallow and narrowly focused. 

M Company, 3M Empore Extraction Disk BioGenesis Enterprises, Inc., Soil and Sediment Washing Process Bioremediation Technology Services, Inc., BTS Method BioSystems Technology, Inc., Chlorinated Solvent Remediation (CSR)... 

Environmental Remediation Consultants, Inc. (ERC) offers the BIO-INTEGRATION method for in sitn and ex situ destruction of organic compounds in soil, sediment, sludge, groundwater, snrface water, and wastewater. The BIO-INTEGRATION approach combines biotic and abiotic treatment methods to remediate subsurface contamination. On-site bioreactors are used to grow substrate- and contaminant-specific microbes. The microbes are combined with abiotic amendments and injected into the subsurface. 

Some caution may be needed when evaluating in situ technologies for the remediation of sediments. In situ treatment of sediments may be less cost-effective than ex situ methods because the treatment level for in situ methods is not uniform and in some cases project goals cannot be met throughout the site (D20043R, p. 6). 

The use of subcritical water extends beyond destruction. A method for remediation of PCB-contaminated soil and sediments has been described that uses zerovalent iron as the dechlorination agent and subcritical water extraction (SWE) as the transporting medium. The initial findings indicate that this technique may be a viable method for remediation of PCB-contaminated soil and sediments (Yak et al., 1999). 

The studies with sediment cultures indicate natural degradation potential for aquatic sediments exposed to anthropogenic CP pollution. However, in situ remediation rates for CP-contaminated sediments may be difficult to enhance. Possibilities involve nutrient and electron donor/acceptor amendments. Ex situ remediation could involve sediment dredging and application of methods developed for soil decontamination, such as slurry reactors and composting. 

Petroleum hydrocarbon sources to North American and worldwide waters were summarized in a report by NRC (2002). In many cases of large petroleum spills, the specihc source of petroleum spill is evident, and no geochemical fingerprinting is required to establish the source. Nevertheless, the inventory of petroleum compounds and biomarkers that are eventually sequestered in bottom sediments need not reflect sole derivation from a single source, even in cases of massive oil spills in the area (e.g., Kvenvolden et al., 1995 Wang et al., 1999). Where a mass balance of petroleum sources is required to properly design remediation or identify a point source, molecular methods for distinguishing sources of hydrocarbons have come to the fore. 

For the use of surfactant for remediation of the hydrophobic aromatic dyes polluted soil or sediment, based on the results presented in this thesis, the solubility enhanced of CAD by surfactant follow by photolytic destruction is a promising method. A further study to examine the application of this technique in different type of soil or sediments to solve the real world problem. Finally, a continuous pilot scale reactor for the dyes removal by both ACO and surfactant soil remediation is needed as a next step to further develop. 

Chemical and toxicological testing showed that nonaerated windrow composting can rapidly reduce extractable explosives, extractable mutagenic activity, and leachable toxicity of explosives-contaminated sediments. It is at least as efficient as the best static pile or mechanically stirred composting methods, based on results of other studies conducted at the same site, and thus is an excellent candidate for remediation of explosives-contaminated soils and sediments. 

Bertsch PM, Seaman JC (1999) Characterization of complex mineral assemblages Implications for contaminant transport and environmental remediation. Proc Nat Acad Sci 96 3350-3357 Bertsch PM, Hunter DB, Sutton SR, Bajt S, Rivers ML (1994) In situ chemical speciation of uranium in soils and sediments by micro X-ray absorption spectroscopy. Envir Sci Techno 28 980-984 Bildeiback DH, Huang R (2001) X-ray tests of microfocusing mono-capillary optic for protein crystallography. Nucl Instrum Methods Phys Res A 467-468 954-967 Bilderback DH, Thiel DJ (1995) Microbeam generation with capillary optics. Rev Sci Instrum 66 2059-2063... 

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