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Project Clear: Efficient Hard Rock Tunneling below St. Louis, Missouri
The Metropolitan St. Louis Water District’s Project Clear is a 28-year program targeting water quality and wastewater capacity throughout St. Louis, MO. The extensive program involves multiple tunnels, including Deer Creek, a 6.3 km long tunnel being bored with the largest TBM ever used in the St. Louis area (6.5 m in diameter). Another tunnel, Jefferson Barracks, is using TBM components that have bored over 40 km of tunnel since 1981.
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