Case Histories of Full-Scale Microbial Bio-Cement Application for Surface Erosion Control

Microbial induced calcite precipitation (MICP) and enzyme induced calcite precipitation (EICP) have been widely studied in laboratories over the last 20 years. In conventional bioaugmentation MICP and EICP treatments, either the bacterium S. pasteurii or the plant-derived urease enzyme, respectively, is combined with a nutrient broth-urea-calcium solution and applied to a soil. Rarely, however, has microbial or enzyme bio-cement technology been taken out of the laboratory and evaluated at field scale under real-world conditions. In this paper, three case histories of full-scale use of surface applied bio-augmentation MICP treatments in rural South Dakota are presented. In all three case histories, MICP was used to provide short-term surface erosion mitigation against rainfall and wind (fugitive dust control). These case histories show the effectiveness of surface applied MICP in surface erosion control along with lessons learned for future research. These case histories also show the environmental effects of MICP on growth of native grasses and plants. In these case histories, the interaction of MICP and vegetation for erosion control is highlighted while MICP and vegetation methods are compared directly.