Life-cycle sustainability assessment of geotechnical site investigation

The life-cycle impacts of site characterization, an important component of most geotechnical engineering projects, are typically not considered in practice nor have they been studied in detail. A life-cycle sustainability assessment (LCSA) was performed to evaluate the environmental and economic impacts of several common site investigation methods. The potential impacts of these methods were computed to provide normalized metrics for the mobilization, drilling, sampling and (or) testing, and borehole sealing phases of the life cycle. These environmental impact and cost metrics were then applied to a “typical” 30 m exploration to compare different site investigation methods. Next, the metrics were used to assess the impacts of small and midsized industry investigation programs to investigate how impacts scale with project size. Scenario analyses were then performed on the midsized project to consider how different mobilization choices, grouting materials, and exploration methods influence total impacts. Collectively, this study provides a reference and framework that allows practitioners to assess environmental impacts in parallel with cost when designing site investigation scopes of work.