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• 2010-06-20 03:47 NortyNort 770×557× (137028 bytes) {{Information |Description = This piece of equipment, named a Jumbo Rig, was designed to speed up the Hoover Dam's tunnel drilling process. Built on the back of a 10-ton truck, 24 to 30 drills could be operated at once. |Source = http://www.u