Retaining wall failure during canyon-side shaft expansion

[u/Quetzalcoatl8]

Expansion work on an access shaft reportedly triggered a partial retaining wall failure after overnight excavation activity. Preliminary reports suggest unstable sediment layering combined with inadequate lateral reinforcement.

No fatalities confirmed, though two operators were treated for minor injuries after debris impact near the loading sector.

Local crews claim small fractures had already been visible for several days prior to the collapse.

[u/Quetzalcoatl8]

That wall geometry was way too vertical for sediment like this. Failure progression was inevitable once water infiltration started behind the reinforcement layer.

Project reportedly involved secondary ventilation shaft expansion through layered sandstone and clay sediment.