CAREER: Subsurface Heterogeneities, Interfaces and Biodegradation: Defining the Limits on In Situ Bioremediation

University Of Maryland, College Park, College Park MD

Investigators

Abstract

Billions of dollars are invested world wide for the remediation of soil and groundwater contamination, making it important that appropriate remedial strategies be selected. In situ technologies are proving to be economical and popular remediation alternatives. One such technology is in situ bioremediation. For in situ bioremediation to be used successfully and economically, additional fundamental research is required to allow for more informed field implementation. The CAREER award will provide an opportunity for the continued development of the PI's research goals in the application and evaluation of in situ bioremediation technologies, as part of a balanced and integrated program of research, education, and scholar/practitioner partnerships that will broaden and enrich the PI's capabilities and contributions. Research: Intrinsic and engineered in situ bioremediation are made technologically challenging by the physically and chemically heterogeneous nature of the subsurface environment. Indeed, subsurface heterogeneities have been identified as an important factor impacting the success of in situ bioremediation since its first application. Despite this, the understanding of the impact of heterogeneities on in situ biodegradation is still relatively limited. The main hypothesis of this research is that a quantitative framework based on a set of dimensionless coefficients can be de eloped that will capture the effects of the competing interfacial- and bio-kinetic processes and define limits on the successful application of in situ bioremediation. This research proposes to rigorously evaluate this hypothesisby developing such a framework and testing it using a combination of numerical modeling and experimentation. Specifically, a systematic and integrated set of modeling and laboratory experiments will be performed. The proposed research will improve the fundamental understanding of the impact of subsurface heterogeneities on in situ bioremediation and will be a step toward the development of a practical, relatively easy to use tool to help practitioners in the field define when in situ bioremediation will work and, if so, whether an engineered or intrinsic approach is best. Education: The overall goal of the proposed education activities is to work to develop the potential of undergraduate and graduate engineering students. Specifically, the educational efforts are focused into two objectives: (1) to test instructional strategies that enhance the problem solving and decision making skills of students, and (2) to develop and promote research activities and productive scholar/practitioner partnerships that provide opportunities for students to develop as researchers and practitioners. To achieve the first objective, a variety of instructional strategies will implemented and tested including: assessment of student learning styles and development of approaches addressing those styles; increased use of cooperative learning via small group discussions featuring controversy, case studies, ethics, and role playing; increased use of experiments, field trips and demonstrations; improved use of technology for Web-based activities and asynchronous learning; and incorporation of research results into classroom teaching. The second objective will be achieved through the continued pursuit of undergraduate research opportunities and improved mentoring of students involved with research. In addition, scholar/practitioner partnerships are being developed that will provide interesting industry-based cases for class discussions and projects, and provide an opportunity for student work experience.