Decontaminating soils with

Bollag JM (1992) Decontaminating soil with enzymes. Environ Sci Technol 26 1876-1881. 

After a demonstration at the U.S. Department of Defense s (DOD s) Tinker Air Force Base in Oklahoma, additional cost estimates were prepared for the LT3 process. The estimated unit cost for processing and decontaminating soil with similar contaminants a rate of 8 tons per hour was 86 per ton. The total estimated costs for treating 5000 tons were 116 per ton. The fixed costs for mobilization, startup, and demobilization were estimated to be approximately 150,000 (D12576I, p. 42). 

Therefore, the problem of effective remediation of soils of radioactive nuclides is very relevant. Most technologies of soil decontamination that are currently developed are based on flushing soils with various chemicals and include processes of chemical leaching and selective extraction of radioactive nuclides (Prozorov et flZ., 2000 Shevtsova, 2003). The electrokinetic technique is a new and perspective method of soil remediation, whose main advantage consists in its applicability to decontaminating soils with low filtration ability directly at the site of its local pollution (e.g. in a rock mass) (Pamukcu and Wittle, 1992 Acar et al, 1993, 2001 Janosy and Piot, 1998 Korolev, 2001, 2006 Korolev, Barkhatova, and Shevtsova, 2007). 

TeRRox A process for decontaminating soil which has been polluted by hydrocarbons by treating it with hydrogen peroxide. Developed by DeGussa and operated at its plant in Knapsack, Germany, from 1996. 

Phytoremediation methods for radionuclide decontamination do not involve hyper-aeeumulators, except possibly for uranium. Plants require a long period of eontact with a contaminant to evolve the ability to hyper-aeeumulate, and most uranium ores are located underground and so are not in eontaet with plants. Soils with high concentrations of uranium are present only where uranium is or has been mined or processed, but these have only been in existenee for a few deeades. 

Recommendation 14. The Army should demonstrate that it has the ability to analyze for agents and their toxic degradation products in concrete, soil, and spent carbon, and to provide assurance that any structures or media left in place will be decontaminated consistent with the island s future use. 

Zhou, K., M.Sc. thesis, Decontamination by Laundering of Textiles Soiled with Iprodione or Pirimicarb, University of Alberta, 1993. 

Dougherty et al. (1993) conducted a theoretical analysis of a proposed in situ method for decontaminating soil by photodegradation. Up to 86% of TCDD in the soil can be degraded by this process (Zhong et al. 1993). Because of its extremely low water solubility and volatility, TCDD is a very persistent soil contaminant. With the method, based on the physical properties that facilitate photolysis... 

At the University of Nevada, a study is underway that is attempting to (1) establish improved methods for analyses of soils for gasoline constituents and (2) determine the utility of using volatilization as a method for decontaminating soils containing gasoline. This field experiment will be conducted under conditions similar to those used in landfarming. The purpose is to demonstrate the relative rates of loss of various petroleum hydrocarbons, with identification of a treatment method that optimizes loss at lowest cost. 

OEC has been used to reduce NOx in a fixed-based resource recovery process.20 Giant Resource Recovery (GRR) is a subsidiary of the Giant Group, Ltd., which is involved with cement manufacture and the use of waste materials as fuel and raw materials supplements. GRR processes creosote-contaminated soil through countercurrent rotary kilns. By a patented process, the decontaminated soil is then used as a raw material for cement production, thus replacing a certain portion of the traditional feed material stream. The combustion products are ducted into the cement kilns. 

A major concern in this type of processing involves the toxicity of any reagents and/or reaction products which may inadvertently be left in the decontaminated soil after treatment. Some toxicity data on reagents used in the process are shown in Table I, along with comparison values for sodium chloride and 2,3,7,8-TCDD. 

The Portable Unit has successfully demonstrated its capability for thermal treatment of hazardous wastes at the source of the material. This type of on-site treatment would eliminate the need of transportation of hazardous materials to a distant site of stationary treatment equipment. The Portable Unit also has demonstrated that it can be moved to a site and be ready to treat material very quickly, a capability which will be very important in operation of full scale equipment. The on-site treatment of the Times Beach dioxin contaminated soil resulted in no dioxin detected in any of the incinerator effluent streams. The product of the testing activity was soil with no detectable level of dioxin. Dioxin contaminated soil thermally treated in this manner will yield soil which can be disposed as non-hazardous material. The decontamination was performed without exceeding RCRA requirements for particulate emissions and with dioxin destruction efficiencies surpassing the required percentage. The overall conclusion was that the infrared incinerator can very effectively remove dioxin from contaminated... 

Soil decontamination tests have demonstrated that the process can effectively decontaminate soils containing up to 10,000 ppm of PCBs and soils or sludge containing 5 percent or less of organics soils with higher contaminant concentrations may be more economically treated by incineration. However, this process can treat soils containing more than 5 percent organics. (See Fig. 3.9.)... 

Abstract Though, naturally occurring and chemically synthesized (pure grade) zeolites have been used for various industrial applications in the past, their increasing demand for several novel applications (viz., as adsorbent or absorbent for waste water decontamination, soil remediation as fertilizers, aqua-culture purification, etc.) warrants their enhanced production. With this in view, several researchers have attempted to synthesize zeolites from the fly ash, an abundantly available industrial by-product, as described in this chapter. Furthermore, different methods employed for synthesis of fly ash zeolites, the mechanism of zeolites formation and potential fields of their appUcations have also been included herein. 

In all cases of anthropogenic contamination of soils with heavy metals, the highest heavy metal concentrations are found rather close to the surface, although not directly in the uppermost few mm to cm as these are leached by rain like in natural heavy metal sites [130,131]. For this reason, a decontamination of such areas is, in principle. 

SFE. SFE has been established as the extraction method of choice for solid samples. The usefulness of SFE for soil samples has been demonstrated for carbamate,organophosphorus and organochlorine pesticides. However, SFE is more effective in extracting nonpolar than polar residues. In order to obtain a greater extraction efficiency for the polar residues of imidacloprid, the addition of 20% methanol as modifier is required. Extraction at 276 bar and 80 °C with a solvent consisting of supercritical carbon dioxide modified with methanol (5%) for 40 min gives a recovery of 97% (RSD = 3.6%, n = 10). It is possible to use process-scale SFE to decontaminate pesticide residues from dust waste. ... 

The TSDF standards also establish requirements to ensure that hazardous waste management units are closed in a manner that protects human health and the environment. The closure provisions require the facility to stop accepting waste remove all waste from management units and decontaminate all soils, structures, and equipment. Some units (i.e., land treatment units, landfills, and surface impoundments) serve as places for the final disposal of hazardous waste. These land disposal units must comply with additional postclosure requirements to ensure proper long-term unit maintenance. 

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