Aboveground treatment technologies

Aboveground Treatment Technologies Used at 70 Groundwater Pump-and-Treat Remediation and Drinking Water Treatment Projects... 

Cost Summary for Pump-and-Treat by Aboveground Treatment Technologies (2000 USD)3... 

These factors may influence the specific aboveground treatment technology that is selected, the possible need for multiple aboveground treatment processes (treatment trains), and the need for pretreatment of groundwater or posttreatment of off-gas. Also, as with the extraction component, the presence of an active source area may result in the need for long-term operation of aboveground treatment systems. 

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. 

Extracted vapors and liquids are commonly treated aboveground. The types of technologies used for aboveground treatment are similar to those used for SVE and groundwater pump-and-treat, respectively, and they are discussed further under those technologies. More detailed information relevant to the application of MPE at sites in general or contaminated with MTBE and other oxygenates is available in Refs [47-49],... 

At a site contaminated with soU concentrations of up to 5000 mg/kg and groundwater concentrations of approximately 60 mg/liter of chlorinated aromatics, SIVE technology remediation took a fraction of the time and cost 30 to 50% less than excavation and aboveground treatment (D10225Q p. 61). 

Traditional environmental cleanup methods include approaches such as excavation and incineration of contaminated soil or pumping and aboveground treatment of groundwater. These techniques are both expensive and politically unpopular. Affordable, innovative technologies are needed by the environmental restoration industry. Bioremediation is such a technology. 

For practitioners of in situ technologies, note that U.S. EPA has issued a policy statement that reinjection of contaminated groundwater is allowed under Resource Conservation and Recovery Act (RCRA)35 36 as long as certain conditions are met. This policy is intended to apply to remedies involving in situ bioremediation and other forms of in situ treatment. Under this policy, groundwater may be reinjected if it is treated aboveground prior to reinjection. Treatment may be by a pump-and-treat system or by the addition of amendments meant to facilitate subsurface treatment. Also, the treatment must be intended to substantially reduce hazardous constituents in the groundwater (either before or after reinjection) the cleanup must be protective of human health and the environment and the injection must be part of a response action intended to clean up the environment.37... 

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