Groundwater treatment

E. J. Bouwer and G. D. Cobb, In Situ Groundwater Treatment Technology EsingBiodegradation, U.S. Army Toxic and Hazardous Materials Agency, Report AMXTH-TE-CR-88023, Washington, D.C., 1987. 

Baird is the 20-acre site of a former chemical mixing and batching company. Poor waste disposal practices resulted in the contamination of groundwater, soil, the municipal water supply, and a brook adjacent to the site. Over one hundred contaminants, including chlorinated and nonchlorinated volatile organics, heavy metals, pesticides, herbicides, and dioxins, had been identified in site soil and groundwater. Remediation activities included soil excavation and incineration, and groundwater treatment (the audit focused on the soil excavation and incineration... 

In situ groundwater treatment is an alternative to the conventional pump-and-treat methods. In situ treatment uses biological or chemical agents or physical manipulations that degrade, remove, or immobilize contaminants. In situ treatment technologies can usually treat both contaminated groundwater and soil. In many instances a combination of in situ and aboveground treatment will achieve the most cost-effective treatment at an uncontrolled waste site. 

The facility would use a dry scrubber system for emission control, which would eliminate the need for wastewater treatment. Any water from emission control and from decontamination procedures would be treated in the on-site groundwater treatment system. The residual soil and collected ash is assumed to be nonhazardous and can be disposed of in a solid waste disposal facility in compliance with subtitle D of RCRA. In the event that they cannot be delisted due to the presence of metals, the residuals will be managed as part of the closure of Area 2 shown in Figure 16.21 (lead-contaminated soil). 

Simple to extend extraction system and cap cap would be sufficient if metals were significant in Area 2 could implement groundwater treatment if necessary... 

Vapor extraction requires some operation fairly straightforward to construct cap construction would require materials handling of 25,000 cy of soil and clay on-site groundwater treatment requires operation... 

Huibregtse, K.R. and Kastman, K.H., Development of a System to Protect Groundwater Treatment by Hazardous Spills on Land, U.S EPA, Edison, NJ, 1979. 

Some integrated techniques may be more economical if they can be used simultaneously for soil and groundwater treatment, such as integrated vapor extraction and steam vacuum stripping. 

The application of containment—the presumptive remedy—often requires the design and installation of a landfill cover. Other common components, such as landfill gas management, groundwater treatment or containment, and collection and disposal of leachate, may also be required. Landfill covers may offer several environmental benefits (minimize erosion, prevent occurrence of disease vectors and other nuisances, and meet aesthetic and other end-use purposes), but they are based on three primary goals.1415... 

Groundwater remediation, activated carbon application, 4 753. See also Groundwater bioremediation Groundwater treatment Groundwater samples, retrieving, 22 844-845, 846... 

An overview of treatment technologies, along with site-specific considerations, and cost comparisons for various approaches that have been utilized for coproduced groundwater treatment are discussed below. These treatment approaches are ... 

Summary of Total Annual Estimated Cost (in Dollars) for Groundwater Treatment Alternatives... 

Most technology used for groundwater treatment was developed for wastewater facilities. Wastewater equipment is usually designed to last a minimum of 20 to 30 years. With continued maintenance, the equipment should survive this long. For the wastewater market, the design is based on the life expectancy of the equipment, not the waste stream. Groundwater treatment equipment systems will typically be in use for a much shorter time the controlling factor is the life expectancy of the project, not the equipment. 

Turner, C.D., Walton, J.C., Moncada, J.D., Tavares, M. Brackish Groundwater Treatment and Concentrate Disposal for the Homestead Colonia, El Paso, Texas. U.S. Department of the Interior, Bureau of Reclamation, Denver (1999)... 

Hager, D.G. Smith, C.E. The UV-hydrogen peroxide process an emerging technology for groundwater treatment. Paper presented at HazMat West 85, Long Beach, California, 1985. 

The closure activities at J AC ADS consist of decontamination and removal of process equipment and building structures and some soil removal and disposal. Although no requirement for groundwater treatment is anticipated at Johnston Island, other CSDP disposal sites might require groundwater treatment, which would affect the closure process and the ultimate postclosure monitoring at those sites. 

The capital cost includes covered tank, carhon feed system. O M costs cited are for groundwater treatment, air emissions control/treatment, sludge dewatering/disposal, and analytical. 

Capital and operations and maintenance (O M) costs are different for leachate or groundwater treatment and depend on design flow of the system and level of treatment. Table 1 gives sample costs for leachate treatment, and Table 2 gives sample costs for groundwater. 

The process can be used to treat dissolved metals and is commonly used in groundwater treatment for the reduction and precipitation of hexavalent chromium, as well as in the oxidation of cyanide wastes (at concentrations up to 10%). Other potential applications of electrochemical treatment include remediation of arsenic, cadmium, molybdenum, aluminum, zinc,... 

Table 1 shows treatment costs for the technology (based on a processing rate of 20 gpm) in comparison to other groundwater treatment technologies (i.e., chemical reduction and precipitation, chemical precipitation with sedimentation or filtration, activated carbon adsorption, ion exchange, reverse osmosis, and electrodialysis) (D168869, Table 13). 

TABLE 1 Comparisons of Costs for Groundwater Treatment Technologies (D168869, Table 13)... 

The evaluation sited a number of factors that could affect process costs for groundwater treatment, including flow rate, type and concentration of contaminants, groundwater chemistry, physical site conditions, site location, availability of utilities, and treatment goals. Assumptions made for the cost estimate include any suspended solids are removed prior to CPFM treatment, the influent has an optimum pH of 8 to 9, and the ambient temperature of the influent is between 20 and 35°C. It was assumed that the system would be operational on an automated, continuous-flow mode, 7 days per week, 24 hours per day. This would lead to approximately 52.4 million gallons of water being treated in a 1-year period (D10957J, p. 22). 

The Chloro-Cat catalytic oxidizer uses combustion followed by catalytic oxidation to treat halogenated organic vapors discharged from soil vapor extraction (SVE) and groundwater treatment systems. The system has been used in the field to treat a variety of volatile and semivolatile... 

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