Edited by author 05-25-2005 04:37 PM
It is now possible to see the amount of green space in the following WTC design with the roof gardens now illustrated
in four corner buildings:

4.7 acres Memorial site.
One to two acres northeast of this, at least 1.5
Perhaps 3/4 acres surrounding the buildings
One to 1.5 acres as roof top gardens, at least one acre.
So there's about 8 to 9 acres of green space.

On Oct 11 2002 in a Vision for Lower Manhattan, the LMDC said: As a densely developed and historically rich place Lower Manhattan has relatively little park and recreational space. This lack of park and open space in Lower Manhattan is a major problem,...

With roof top gardens, please see WTC Architectural Images, looking north, image 1. at:
http://www.geocities.com/buildingpreservationtech/index.html