blowout

excavation

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June 22, 2026

Quick Summary

The term "blowout" can refer to extinguishing something with a gust of air, defeating something easily, or severely damaging something, such as an injury. In the context of tunneling and excavations, a blowout is a dangerous event where compressed air inside a tunnel escapes, leading to a loss of pressure and potentially the collapse of the tunnel as soil enters.12

"Excavating" means to hollow out or form something by removing earth, such as digging a tunnel. When excavating below the water table, there's a risk of a "run-in," where soil and water flow into the tunnel. This can be managed by lowering the water table or using compressed air within the tunnel to counteract external water pressure.32

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tunnels and underground excavations
Water control
Otherwise, a blowout could occur, depressurizing the tunnel and possibly losing the heading as soil enters. Compressed air greatly increases operating costs, partly because a large compressor plant is needed, with standby equipment to insure against loss of pressure and partly because of the slow movement of…
Read More
Otherwise, a blowout could occur, depressurizing the tunnel and possibly losing the heading as soil enters. Compressed air greatly increases operating costs, partly because a large compressor plant is needed, with standby equipment to insure against loss of pressure and partly because of the slow movement of…
Read More