A conveyor belt runs along one of the canyon benches at the copper mine. The upper slope of the canyon was undergoing a slow and predictable landslide transverse to the conveyor belt. To protect the conveyor belt from falling debris due to the potential slope collapse, the mine operator built a corrugated steel arch tunnel embedded within a mechanically stabilized earth (MSE) wall. SGH evaluated the tunnel structure and helped the mine operator establish a monitoring program to identify when the tunnel exceeded its ability to support additional load.