Mountain View Boulevard sits underneath a sandstone cliff overlooking the city. This past June, a boulder estimated to weigh over 50 tons fell from the cliff and rolled past Mountain View Boulevard where it subsequently damaged a residence and destroyed a vehicle. GeoStabilization’s Rockfall Remediation Technicians (RRTs) were dispatched to assess the scene and help validate a solution to prevent similar rockfall events from reoccurring along the rim. Working closely with geologists from Terracon, the team developed a solution to bring down the remaining unstable material threatening the structures below. Because of the proximity of houses below the rim, blasting the material out was not feasible. The team instead chose to scale the boulders with pneumatic lifting bags in a controlled manner. Before the work began, GeoStabilization’s engineers inquired about possible underground utilities and learned that a gas line was buried beneath the road. To protect the line, and more importantly the houses below, an earthen berm was constructed to contain falling material and limit the run out during the scaling process.
GeoStabilization’s RRTs began their work by removing a 200-ton rock slab perched precariously on the rim. They then removed smaller boulders along the slope face. The project was a success; the earthen berm successfully contained the material, protected the underground utility, and none of the rocks removed will ever be able to threaten the lives and infrastructure along Mountain View Boulevard again.
To learn more about the project, click here.
A variation of karst sinkhole grouting is the grouting of mined coal seams and workings located below existing infrastructure that exhibit the potential to propagate to the surface and cause sinkholes and/or subsidence.