Engineering report re: structural inspection, Nov 2001

NYC 9/11 Public Portal Document

ACT-2588 Page 2

The other crack occurs in the front wall at approximately the same location. This crack is similar in nature to the crack in the rear wall. It starts as a large crack at the top of the wall and tapers as it extends down the building. At the top, the crack is approximately V2 inch wide and appears to go through the entire width of the wall. In addition, similar to the rear of the building, the coping stone has separated at the location of the crack. This crack, however, has been previously repaired and sealed with roofing cement indicating a pre-existing condition.

In addition to the cracks in the exterior wall, we observed a large vertical crack in the interior bearing wall during a walk through of the 4th floor. The crack is located at approximately the middle of the space and extends the entire height of the wall. The crack appears to have been previouslyirepaired, indicating that it was a pre-existing condition. Also, it was evident from our walk through that the floors slopes toward the rear ofthe building.

The nature of the wall cracks, along with the sloping floor structure at the 4th floor, are consistent with a settlement problem. Therefore, it is our professional opinion that the cracks in the front and rear masonry walls are the result of differential settlement of the building foundations.

Based on our inspection, we conclude that the observed masonry cracks at the front and rear building walls are not the result of the World Trace Center collapse, Furthermore, these cracks do not represent a safety issue to the building. We do, however, recommend that the walls be repaired as soon as possible to prevent further damage. The method of repair is beyond the scope of this report; however, Acticon is available to make recommendations for the repair of the wall upon your request.

Should you have any questions~regarding this evaluation or need additional information, please do not hesitate to call. rdial~y,

Maurice Cueva-E P.E. Engineering Manager MC-E:sp Attachment - Photographs cc: T. Muabile

NYC-WTC 000104843