Soil and groundwater cleanup: benefits and limits of emerging technologies

Contaminated soil and groundwater have been the subject of study and research, so that the field of remediation has grown and evolved, continually developing and adopting new technologies in attempts to improve the decontamination. The cleanup of environmental pollution involves a variety of techniques, ranging from simple biological processes to advanced engineering technologies. Cleanup activities may also address a wide range of contaminants. This article is a short analysis of the technologies for cleaning up groundwater and soil, highlighting knowledge and information gaps. Challenges and strategies for cleaning up different types of contaminants, mainly heavy metals and persistent organic compounds are described. Included are technologies that treat ground water contaminants in place in the subsurface and soil technologies that treat the soil either in place or on site in a treatment unit. Emerging technologies such as those based on oxidation-reduction, bioremediation, and nanotechnologies are covered. It is evident that for a good efficiency of remediation, techniques or even whole new technologies may be incorporated into an existing technology as a treatment train, improving its performance or overcome limitations. Several economic and decision-making elements are developed in the final part, based on the analysis carried out throughout the article. The work highlights the fact that excellence in research and technology progress could be attained by the development of technologies to deal more effectively and economically with certain toxic contaminants such as heavy metals, volatile organic compounds, and persistent organic pollutants, associated with optimization of technologies under field remediation conditions and requirements, improving capacity and yields, and reducing costs. Moreover, increasing knowledge of the scope and problem of equipment development could improve the benefits.