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For immediate release: April 5, 2013
Contact: Dan Weiller, (518) 471-5300

Preconstruction Geotechnical Investigations Continue

Tappan Zee Constructors, LLC will continue conducting preconstruction geotechnical surveys to determine soil conditions in and near the Hudson River.

Geotechnical operations will expand over the next week with additional barged-based boring equipment arriving on site.  Two additional units will begin work in the river bringing the total number to four. 

On March 25, barge-based operations began work conducting additional engineering analyses of the river bottom, following up on the "smart early work" that was completed in 2012. Tappan Zee Constructors, LLC, is conducting these tests to help ensure the designers utilize properly-sized piers and supporting foundations for the new bridge.  The testing operations are being conducted by small drilling rigs starting near the tower locations and working their way across the river. Noise levels from the equipment will be at a minimum. The river-based operations will run continuously 24 hours a day Monday through Friday and possibly Saturday. 

This geotechnical work is scheduled to take approximately eight weeks total, with six weeks remaining until completion.    

Hydrographic surveys will be conducted as part of the geotechnical investigations.  Tappan Zee Constructors is utilizing complex hydrographic analysis to map the river bottom at the location of the new bridge.  The hydrographic survey is conducted with sonar which utilizes sound waves to create an image of the floor of the Hudson River.  The survey will show the depths of the river, the channel locations, and any underwater structures both manmade and natural.  The operations will be done periodically over the next few weeks.

Survey crews will also be conducting design surveying at various locations in Rockland and Westchester in the vicinity of the project.

There will be limited boring operations conducted on land under the existing bridge and just to the north at the proposed bridge locations.  These operations are being conducted on Thruway property and will not affect traffic in any way.  The work is scheduled to be conducted between the hours of 7 am and 5 pm Monday through Friday.

There are no boring operations on land scheduled for the Rockland area for the week of April 8.

Site preparation work and cleanup is being conducted at the Interchange 10 staging area in South Nyack. That work will be done weekdays between 7 am and 4 pm.



Andrew M. Cuomo

New York State
Thruway Authority

Federal Highway

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