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Based in San Francisco , Bechtel Group was established in 1898 . Its current employee base numbers over 50,000 with ongoing projects in industries such as government services , infrastructure , telecommunications and more established throughout the world . Just a few of the noteworthy projects the company has undertaken include the Channel Tunnel , the Hoover Dam and the Tacoma Narrows Bridge . It posted $ 32.3bn in sales in 2015 .

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