Geneva, Switzerland - May 22, 2014: Two workers preparing the machine for the construction of piperoof grouting for a tunnel

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Size: 3648px × 5472px
Location: Geneva, Switzerland
Photo credit: © Oliver Förstner / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: boring, building, chamber, concrete, constructing, construction, digging, dirt, drill, drilling, engineer, engineering, excavation, front, geology, grouting, machine, machinery, metro, mineral, mining, piperoof, power, securing, site, soil, subway, support, supporting, switzerland, train, tunnel, tunneling, underground, worker, working