Geohazard & Risk Assessment, Cerro Casale Access Road

CH33 is a two-lane, sinuous, dirt road that accesses the Cerro Casale Mining Project in Chile.  The road climbs into the Andes Mountains from Copiapó to the project location near the Argentine border at an elevation of over 3400 m.  BGC was retained to complete a linear geohazard and risk assessment for a 140 km section of the road. The aim of the study was to identify geohazards and associated health risks to road users, as well as to develop mitigation concepts to reduce risk to tolerable levels.

The assessment involved three specific tasks:

1. Quantify hazards and risks due to flooding, stream avulsions, bank erosion, debris flows, rock fall, and other landslide types
2. Provide design input for cut slope designs at road modification points
3. Suggest conceptual geohazard mitigation strategies

BGC characterized geohazards and estimated frequency at 200 road segments.  The risks associated with each geohazard were estimated using a semi-quantitative method to compare each site and prioritize risk reduction measures.  BGC also developed a linear risk map that indicates hazard type and risk rating for all road sections, enabling the mining company to allocate funds substantially more cost effectively.