skip to main content


Search for: All records

Award ID contains: 1632963

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. The controlled production of microbial growth has the potential to reduce groundwater flow in seepage and dewatering systems. Stimulating the growth of indigenous bacteria could clog the pore space and result in a substantial permeability reduction. This study investigated the spatial distribution of permeability reduction under different nutrient stimulation treatments of indigenous bacteria across 16 cm columns of Ottawa 50-70 sand. Spatially uniform permeability reductions of up to an order of magnitude were achieved using both a high glucose (50 mg L-1) and a low glucose (10 mg L-1) nutrient formulation. The overall permeability began to drop by day 2 and generally reached a minimum permeability by day 14. There was no noticeable difference in the final permeability nor the rate of permeability reduction between high and low glucose formulations. Upscaling of experiments is highly recommended for future studies on the spatial uniformity of microbial growth and biologically induced permeability reductions. 
    more » « less
  2. This paper presents a novel laboratory experiment that can be incorporated into introductory soil mechanics courses to introduce students to the field of biogeotechnical engineering and the use of biostimulated microbially induced calcite precipitation (MICP). Applying MICP to granular soils results in an increase in peak strength and shear stiffness of the soil as a result of the precipitation of calcium carbonate on soil particle surfaces and at soil particle contacts. The authors developed protocols to treat small volumes of soil and to test the effectiveness of the treatment using a simple strength test based on ASTM D3967-16. In fall 2020, the experiment was piloted as a four-week, course-based research experience that can be conducted by students remotely or in a traditional laboratory environment. This paper provides an introduction to MICP and describes the protocols for conducting the experiment. The paper also suggests approaches for how the experiment can be incorporated into a traditional introductory soil mechanics course. 
    more » « less
  3. Growing biofilm in saturated sand has been shown to reduce the permeability of soil by one or more orders of magnitude and may be a viable approach to reducing seepage in the field; however, obtaining laboratory permeability results in soil samples where biofilm is being developed is difficult. Adding nutrients results in the formation of biofilm in the soil but also the formation of biofilm in the piping and other areas of the permeability testing apparatus. In addition, some bacteria produce gas as a product of metabolism and this gas can collect in the apparatus and interfere with fluid flow. This paper presents an approach to permeability testing that effectively minimized the growth of biofilm and the collection of gas in the testing apparatus for multiple sand samples treated with a nutrient solution over a period of more than 60 days. 
    more » « less
  4. In August 2016, the authors, faculty members at Lafayette College, were awarded a National Science Foundation (NSF) grant (Grant No. CMMI-1632963) based on an unsolicited proposal to the NSF’s CMMI Division. Like many faculty at strictly undergraduate institutions, we routinely provide opportunities for students to work on research projects and fund this research in some situations through external grants. An innovation in this particular grant was the creation of a research collaboration between faculty and students at Lafayette and an NSF-funded Engineering Research Center (ERC). As stated on the NSF website, “The goal of the ERC Program is to integrate engineering research and education with technological innovation to transform national prosperity, health, and security.” To accomplish this goal, collaborations between ERCs and other institutions are inherent in the work of an ERC; however, research collaborations between ERCs and small liberal arts colleges are rare and we know of no other collaboration of this type. In our most recent research project, we have developed and implemented a model that successfully provides our students and ourselves with opportunities to collaborate on an interdisciplinary research project with faculty, researchers, and graduate students at the NSF-funded Center for Bio-mediated and Bio-inspired Geotechnics (CBBG). This paper provides a brief overview of the goals of the research project and describes our motivation for establishing the collaboration, the structure of the collaboration, the anticipated broader impacts associated with the work, and the results from the first 18 months of the partnership. A logic model is included to illustrate the connections between the resources, strategies, outcomes, and long-term impacts associated with the collaboration. The goal of this paper is to describe the collaboration between Lafayette College and the ERC from the point of view of the faculty members at Lafayette, to describe the positive outcomes that have resulted from this collaboration, and to encourage faculty members at other small colleges to consider developing similar collaborations. 
    more » « less
  5. In August 2016, the authors, faculty members at Lafayette College, were awarded a National Science Foundation (NSF) grant (Grant No. CMMI-1632963) based on an unsolicited proposal to the NSF’s CMMI Division. Like many faculty at strictly undergraduate institutions, we routinely provide opportunities for students to work on research projects and fund this research in some situations through external grants. An innovation in this particular grant was the creation of a research collaboration between faculty and students at Lafayette and an NSF-funded Engineering Research Center (ERC). As stated on the NSF website, “The goal of the ERC Program is to integrate engineering research and education with technological innovation to transform national prosperity, health, and security.” To accomplish this goal, collaborations between ERCs and other institutions are inherent in the work of an ERC; however, research collaborations between ERCs and small liberal arts colleges are rare and we know of no other collaboration of this type. In our most recent research project, we have developed and implemented a model that successfully provides our students and ourselves with opportunities to collaborate on an interdisciplinary research project with faculty, researchers, and graduate students at the NSF-funded Center for Bio-mediated and Bio-inspired Geotechnics (CBBG). This paper provides a brief overview of the goals of the research project and describes our motivation for establishing the collaboration, the structure of the collaboration, the anticipated broader impacts associated with the work, and the results from the first 18 months of the partnership. A logic model is included to illustrate the connections between the resources, strategies, outcomes, and long-term impacts associated with the collaboration. The goal of this paper is to describe the collaboration between Lafayette College and the ERC from the point of view of the faculty members at Lafayette, to describe the positive outcomes that have resulted from this collaboration, and to encourage faculty members at other small colleges to consider developing similar collaborations. 
    more » « less