London Mine, American Shaft – Vertical Shaft Bulkhead
Client: State of Colorado Division of Minerals & Geology
Location: Alma, Colorado, United States

This project included the underground shaft collar stabilization and polyurethane foam grouting of the American shaft at the London Mine near Alma, Colorado. The purpose was to affect both a safety closure and retard groundwater ingress and provide shaft collar stabilization and closure.

Working at over 11,000’ elevation, MES’ crew hung from ropes to stabilize or remove rotten shaft cribbing, stripped ladders and landings, installed a bottom form and steel dowels into the shaft ribs, installed a 40- foot thick vertical polyurethane foam shaft plug to seal off water ingress at the colluvium/bedrock contact.