Remedial alternatives

If the RFA or other information has indicated a release of hazardous constituents, then from the owner/operator s perspective, the Corrective Action process truly begins. The first step in the process, the RCRA Facility Investigation (RFI), is directed toward development of the engineering information about the site necessary to permit selection and evaluation of remedial alternatives. The main engineering thrust of the RFI is the characterization of site conditions by defining the nature and extent of the problem. 

Phytoremediation is considered a low-cost remediation alternative for low-depth contamination, offering a permanent solution and improving the aesthetics of the polluted site. It is well-suited for use in the following situations ... 

Evaluating the need for a treatability study. The requirement and schedule for treatability studies so as to better evaluate potential remedial alternatives are identified. If remedial actions involving treatment have been identified for a site, then the need for treatability studies should be evaluated as early as possible in the RI/FS process. This is because many treatability studies may take several months or longer to complete. 

Determining if data are sufficient for developing and evaluating potential remedial alternatives... 

The feasibility study (FS) utilizes the data on site characterization and remedial technology screening to establish remedial alternatives, in turn, to select the cost-effective remedial actions. The FS may be viewed as occurring in three phases ... 

The bioreactor landfill is a remedial alternative that can be applied either on site or off site. However, landfilling is regarded as the least attractive alternative at a site cleanup action. Landfilling of hazardous materials is becoming increasingly difficult and more expensive due to steadily growing regulatory control.92-93... 

This case example illustrates how the results of individual and comparative analyses of remedial alternatives may be presented in a feasibility study report. The study uses a U.S. EPA example12 that focuses on a detailed analysis of the alternatives that had been selected after screening. 

Table 16.9 lists five remedial alternatives and their primary components. The nonaction alternative (Alternative 1) provides a baseline for comparison of other alternatives. Because no remedial activities will be implemented with the nonaction alternative, long-term human health and environmental risks for the site essentially will be the same as those identified in the baseline risk assessment. All other action alternatives with action have four common components ... 

After a performance requirement has been established for remediating a particular landfill, any remedial alternative meeting that requirement can be selected and applied. Site-specific requirements are discussed in more detail in Refs. 8 and 13. 

Runkel, R.L. Kimball, B.A. 2002. Evaluating remedial alternatives for an acid mine drainage system - application of a reactive transport model. Environmental Science Technology, 36, 1093-1101. 

Designing an effective air sparging system is as much art as science. In its best form, it has the potential to provide an effective and efficient remedial alternative. If it is poorly designed and operated, air sparging can lead to adverse environmental consequences. 

Stanforth, M. T., Kulik, E. J., Appel, G, and Hafenmaier, M. E, 1998, Case Study DNAPL Remediation Alternatives Evaluation Yields Surprising Results In Nonaqueous-Phase Liquids-Remediation of Chlorinated and Recalcitrant Compounds (edited by G. B. Wickramanayake and R. E. Hinchee), Battelle Press, Columbus, OH, pp. 161-168. 

LNAPL product was found to be distributed over the central portion of the site with measured apparent thicknesses of approximately 0.2 to 0.5 ft. Concluding that additional work was warranted at the site, two goal-oriented objectives were developed (1) consideration of on-site remedial alternatives to prepare the site for other industrial uses and (2) determination of the extent of off-site groundwater contamination. 

Natural attenuation was favorably received and approved as an appropriate remedial alternative for these two sites. Periodic gauging and monitoring of key parameters will continue for a minimum period of 2 to 3 years to demonstrate continued stability and/or decline in dissolved BTEX prior to site closure. 

Testa, S. M. and Colligan T., 1994, Cleaning Up Sites Naturally An Often Ignored Remedial Alternative In Proceedings of the National Water Well Association American Petroleum Institute Conference on Petroleum Hydrocarbons and Organic Chemicals in Ground Water, Houston, TX, 1994, pp. 289-303. 

REMEDIATION ALTERNATIVES ON HIGH TOXICITY AND DANGEROUS SITES... 

An advantage of Aquaplant is that it can be an effective remediation alternative that requires minimal investment due to low operating costs. Also, Aquaplant is typically and more acceptable than an industrial water treatment facility. 

Potentially allows for remediation alternatives by improving performance of in situ techniques. 

Autry, A. R. Ellis, G. M. (1992). Bioremediation an effective remedial alternative for petroleum hydrocarbon-contaminated soil. Environmental Progress, 11, 318-23-Block, R., Stroo, H. Swett, G. H. (1993). Bioremediation - why doesn t it work sometimes Chemical Engineering Progress, 89 (8), 44-50. 

HOC distribution coefficients (KD) between the immobile and mobile compartments varied as a function of solution chemistry and surfactant dose, KD values increased with increasing surfactant dose at low surfactant concentrations, but decreased at higher doses. This trend indicates that competition for HOC partitioning occurs between sorbed- and micellar-phase surfactants. Overall, the results of this study demonstrate that retardation of HOCs by surfactants sorbed to the solid phase can be significant and must be considered for proper evaluation of treatment/remediation alternatives that use surfactants. 

The decisionmaking method adopted in the Proposed Revisions to the NCP is a case-by-case method where analysis and consideration must be given to a range of alternatives which have been selected and analyzed. Cost, feasibility, adequacy, reliability, and potential adverse impacts on health or the environment must be analyzed. Any appropriate Federal and State standards and criteria are to be considered. Finally, under proposed Section 300.67(j) the lead agency is "to choose the most cost effective remedial alternative which effectively minimizes and mitigates the danger and provides adequate protection of public health, welfare, and the environment." (11)... 

Office of Emergency and Remedial Response. 1991. Risk assessment guidance for Superfund human health evaluation manual risk evaluation of remedial alternatives. Vol. 1, Part C, Publication 9285.7-01C. Washington (DC) US Environmental Protection Agency. 

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