Trichloroethene, TCE

Ewers J, Freier-Schroder D, Knackmuss H-J. 1990. Selection of trichloroethene (TCE) degrading bacteria that resist inactivation by TCE. Arch Microbial 154 410-413. 

For trichloroethene (TCE), the stoichiometric amount of iron and the effect of different preparations determine the outcome of the several competing reactions. Coupling products such as butenes, acetylene and its reduction products ethene and ethane, and products with five or six carbon atoms were formed (Liu et al. 2005). Although a held-scale application successfully lowered the concentration of TCE, there was evidence for the formation of the undesirable di-l,2-dichloroethene and 1-chloroethene (vinyl chloride) in the groundwater (Quinn et al. 2005). 

Sturchio et al. [614] explored the use of Cl isotope ratios for investigating the natural attenuation of trichloroethene (TCE) at a well-characterized field site in western Kentucky and ranking the site in terms of its potential for TCE anaerobic biodegradation. 

At the beginning of this study, concentrations of benzene and trichloroethene (TCE), although low, were well above drinking water standards, and implementation of some treatment strategy was necessary. (From Richmond et ah, 2001)... 

At an abandoned manufacturing facility in Emeryville, California, the groundwater was contaminated with hexavalent chromium and up to 12,000 micrograms per liter (p,g/liter) of trichloroethene (TCE). A pilot-scale demonstration of in situ reactive zones using molasses was conducted in 1995 and 1996. In 1997, the project was expanded to a full-scale application. The full-scale system used 91 temporary injection points to deliver molasses to the subsurface. The overall project cost was approximately 400,000 (D210571, p. 90). 

The ARS Technologies, Inc., Ferox process is an in situ remediation technology for the treatment of chlorinated hydrocarbons, leachable heavy metals, and other contaminants. The process involves the subsurface injection and dispersion of reactive zero-valence iron powder into the saturated or unsaturated zones of a contaminated area. ARS Technologies claims that Ferox is applicable for treating the following chemicals trichloroethene (TCE), 1,1,1-trichloroethane (TCA), carbon tetrachloride, 1,1,2,2-tetrachloroethane, lindane, aromatic azo compounds, 1,2,3-trichloropropane, tetrachloroethene (PCE), nitro aromatic compounds, 1,2-dichloroethene (DCE), vinyl chloride, 4-chlorophenol, hexachloroethane, tribromomethane, ethylene dibromide (EDB), polychlorinated biphenyls (PCBs), Freon-113, unexploded ordinances (UXO), and soluble metals (copper, nickel, lead, cadmium, arsenic, and chromium). 

Based on data from the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) demonstration, the total cost for PF extraction was estimated to be 307/kg of trichloroethene (TCE) removed. This demonstration was conducted over a 4-week period in August and September of 1992 at an industrial site in Somerville, New Jersey. The cost estimate includes expenses associated with both PF and soil vapor extraction. Major cost factors were labor (29%), capital equipment (22%), VOC emission control (19%), site preparation (11%), and residuals management (10%) (D10589F, p. v). 

In 1989, a 510-liter/min Perox-Pure system used 15 kW of power to remove trichloroethene (TCE) from groundwater at a municipal drinking water well in Arizona. The O M costs were estimated to be approximately 0.28 per 1000 gal of water treated. Based on a price of 0.06/kWh, the unit consumed 0.11 of electricity to treat 1000 gal of drinking water. A 50% hydrogen peroxide solution at a price of 0.35/lb was added to the system. For each 1000 gal of treated water, hydrogen peroxide contributed 0.12 to the total costs. Maintenance requirements were estimated at approximately 0.05 per 1000 gal of water (D19079Y, p. 3-3 D10057S, p. 60). 

Former Motorola Facility, Arcade, New York 4500 yd of soil Trichloroethene (TCE), toluene, ethylbenzene, and xylene 500,000... 

An antibiotic-resistant bacterium, Dehalococcoides ethenogenes strain 195, that Cornell University researchers isolated from sewage sludge, has been found to remove all the chlorine from organic solvents such as tetrachloroethene (PCE) and trichloroethene (TCE) by halorespiration to form ethene, an innocuous end product. 

According to the vendor, bench-scale results indicate that RPT technologies can be cost effective. Based on early experiments treating trichloroethene (TCE), costs were estimated at 2.64/lb of TCE converted. The vendor states that this amount is much less than the cost of treatment nsing absorption on activated carbon (estimated at 40/lb) (D18003A, p. 25). 

In 1991, an EXXFLOW/EXXPRESS system was combined with an air stripper to remediate groundwater contaminated with chromium and trichloroethene (TCE) beneath an abandoned manufacturing plant in Newbury Park, California. System equipment cost approximately... 

In 1998 and 1999, the Geo-Cleanse process was used to treat 16,500 gal of groundwater contaminated with trichloroethene (TCE) at the DOD s Naval Air Station in Pensacola, Florida. According to the vendor, the total cost for the demonstration was 178,338. Approximately 97,018 of the total were capital expenses and the remaining 81,320 covered operation and maintenance costs. The costs associated with electrical power and water supply were not included in the final cost figure (D21045X, p. 127). 

During the pilot-scale field demonstration in Watertown, Massachusetts, two-zone plume interception treatment technology was used to treat a lO-ft-by-20-ft surface area of groundwater contaminated with trichloroethene (TCE) and tetrachloroethene (PCE). The total costs of the project from November 1996 through November 1997 were approximately 150,000 (D21041T, p. 104). 

Between 1993 and 1994, UVB technology was demonstrated at a solvent disposal site on the DOD s March Air Force Base in California. The capital cost for one UVB well was approximately 180,000. First and second year O M costs were approximately 75,000 and 42,000, respectively. The treatment costs for the trichloroethene-(TCE)-contamination was approximately 260 per 1000 gal of treated groundwater. The UVB well was designed to treat 1,000,000 gal per year (D188709, p. 9). 

ISOTEC is a technology that uses the periodic injection of hydrogen peroxide and proprietary catalysts to oxidize organic contaminants in situ. According to the vendor, this technology can treat soil and groundwater contaminated with chlorinated compounds, petroleum hydrocarbons, polychlorinated biphenyls (PCBs), trichloroethene (TCE), tetrachloroethene (PCE), pesticides, herbicides, as well as benzene, toluene, ethylbenzene, and xylene (BTEX). The ISOTEC technology is commercially available. 

The vendor claims that using ozone to treat a 1-acre site contaminated with 1 part per million (ppm) trichloroethene (TCE) would cost approximately 269,000. This estimate assumes 20 ft of thickness. Treating the same site using alternative oxidants would be less expensive. Hydrogen peroxide would cost about 201,000, sodium manganate would cost about 187,000, and potassium manganate would cost about 136,000 (D203816, p. 6). 

In 1993 through 1994, an IRV-100 thermal desorption unit was used to treat 13,986 yd of soil contaminated with trichloroethene (TCE) at the U.S. Department of Defense s (DOD s) Letterkenny Army Depot Superfund Site in Chambersburg, Pennsylvania. The total project costs were 5,402,801. This figure included 4,647,632 for McLaren/Hart s application of the thermal treatment, 192,827 for the DOD s design and projeet remediation, 249,320 for the DOD s design contract, and 312,320 for the DOD s construction contract management (D21039Z, p. 59). 

The vendor states that tetrachloroethane (PCE), trichloroethene (TCE), and other volatile compounds are difficult to remove from saturated soils because they are relatively insoluble. The vendor states that the technology is especially applicable to sites contaminated with dense non-aqueous-phase liquids (DNAPLs). Using the ISSZT technology creates an unsaturated zone from which these contaminants can be readily air stripped. Other contaminants such as polychlorinated biphenyls (PCBs) or metals can be isolated from groundwater and contained within barriers preventing the spread of contamination. 

PerkinElmer, Inc. (formerly EG G, Inc.), reports that NoVOCs installations have treated sites contaminated with benzene, toluene, ethylbenzene, xylene, trichloroethene (TCE), tetra-chloroethene (PCE), and petroleum hydrocarbons. The technology is unlike conventional pump-and-treat technologies in that it avoids the necessity of pumping water above ground for... 

According to the vendor, the total cost for treating an estimated 9800 m of contaminated soil at the Sweden 3 Chapman site, in Sweden, New York, for a 12-month duration was 52/m of soil (D18722Y, p. 134). Soil at this site was contaminated with trichloroethene (TCE), tetrachloroethene (PCE), acetone, methylethyl ketone (MEK), methyl isobutyl ketone (MIBK), toulene, and xylene. 

The SBP slurry-phase bioremediation system can treat a wide range of organic contamination, especially wood-preserving wastes and solvents. A modified version can also treat polynuclear aromatic hydrocarbons (PAHs) such as creosote and coal tar pentachlorophenol (PCP) total petroleum hydrocarbons (TPH) and chlorinated aliphatics, such as trichloroethene (TCE). The technology can be combined with SBP s membrane filtration system to form a soil cleaning system to handle residuals and contaminated liquids. 

The technology was used at the Cape Canaveral Air Station in Florida to treat 10,000 tons of soil contaminated with PCBs and trichloroethene (TCE). The vendor states that the cost of this full-scale apphcation was less than 120 per ton (D22659P, p. 6). 

In order to degrade trichloroethene (TCE) contaminating some groundwater at 5 /nM (660 ppb), you want to inject toluene (for structure see P 17.1) and 02 below ground and grow a bacterial community capable of growing on the toluene and simultaneously co-metabolizing the TCE (after McCarty et al., 1998.)... 

Mean aqueous concentrations of trichloroethene (TCE) in a contaminated aquifer were measured to be 25 ig/L. The water table is located 4 m below the soil surface. The saturated zone has a mean thickness of 50 m and an average porosity ( ) of 0.3. Water temperature in the aquifer is 10°C. 

In Illustrative Example 22.4 we reanalyze the case of the flux of trichloroethene (TCE) from a contaminated aquifer through the unsaturated zone into the atmosphere. As pointed out in Illustrative Example 19.2, measurements of TCE in the soil indicate that vertical advection of air may influence the TCE profile and the flux. 

In Illustrative Example 19.2 we discussed the flux of trichloroethene (TCE) from a contaminated aquifer through the unsaturated zone into the atmosphere. The example was based on a real case of a polluted aquifer in New Jersey (Smith et al., 1996). These authors compared the diffusive fluxes, calculated from measured TCE vapor concentration gradients, with total fluxes measured with a vertical flux chamber. They found that the measured fluxes were often several orders of magnitude larger than the fluxes calculated from Fick s first law. In these situations the vapor profiles across the unsaturated zone were not always linear. The authors attributed this to the influence of advective transport through the unsaturated zone. In order to test this hypothesis you are asked to make the following checks ... 

Dehalogenation can occur by several reductive pathways. The simplest results in replacement of a C-bonded halogen atom with a hydrogen and is known as hydrogenolysis or reductive dehalogenation. The process is illustrated for trichloroethene, TCE,... 

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