Bridging above and below: A multi-criteria evaluation of GeoBIM modelling workflows for contamination assessment-the...

Soil remediation is a key requirement to sustainable urban regeneration, but planning is hampered by poor integration of geological, environmental and construction data. This study evaluates GeoBIM as an operational framework to integrate subsurface information in BIM for the Parco della Salute redevelopment (Turin, Italy). Four workflows, each representing a distinct subsurface modelling methodology, were developed to convert borehole stratigraphy and laboratory pollutant concentrations into BIM-compatible models. Workflows were ranked through an Analytical Hierarchy Process based (AHP) multi-criteria decision analysis using Key Performance Indicators (KPIs) for reliability, automation, interoperability and usability; KPI weights followed a hybrid 70/30 expert-literature scheme. Results reveal a clear trade-off across KPI groups. Voxel-based GIS pipelines achieved the highest performance for reliability-related KPIs, preserving spatial heterogeneity and depth-continuous concentration patterns while maintaining traceability to sampling intervals and enabling rapid querying for risk screening. Parametric BIM-centered pipelines scored higher on automation and BIM integration, leveraging scripting to reduce manual steps and supporting faster iterations within federated models. Interoperability was the main limiting factor across all workflows: loss of georeferencing and weak environmental semantics reduced downstream reuse. Across downstream use scenarios, voxel outputs were more effective for remediation decision-support, whereas parametric outputs better supported clash detection and construction planning. Overall, results support phase-specific workflow selection: voxel models for investigation and remediation design, and parametric BIM models for construction coordination and delivery.