Geotechnical landside hazard assessments in Presumpscot Formation (Maine, USA)

Large-scale retrogressive landslides pose geotechnical challenges in glaciomarine clay regions such as eastern Canada (eastern Ontario and Quebec) and Scandinavian countries. Similar geological formations exist in neighbouring provinces and countries, but the geotechnical engineering practices for assessing large-scale landslide hazards may differ from those in major landslide-prone areas. This paper introduces a Retrogressive Landslide Hazard Matrix developed as part of a corridor study within the Presumpscot Clay in Maine, USA, based on currently published methods applicable to Champlain Sea Clay in Eastern Canada. For this project, Nilcon vane tests and Swedish fall cone tests were included alongside routine geotechnical investigations and laboratory testing programs typically used in Maine, to ensure adequate input data was available for employing assessment methods currently utilized in Eastern Canada.