Abstract:This study evaluates the environmental and economic impacts of five ground improvement methods for the possible redevelopment of Treasure Island in San Francisco, California. Each method is required to meet a deterministic performance criterion to minimize susceptibility to liquefaction triggering, defined as a normalized standard penetration test (SPT) blow count of 15 or greater. For each improvement method, the study quantifies the resources and emissions flows over the entire life cycle from raw material extraction through the end of construction operations and evaluates the primary energy, global warming potential, acidification potential, smog formation potential, raw project cost, and social cost of carbon. Sensitivity analysis was performed to evaluate assumptions regarding materials selection and transport distances, and a scenario analysis was conducted to compare multiple improvement scenarios for the Treasure Island redevelopment project. The study concludes that the most environmentally preferable combination of improvement methods does not include deep soil mixing.