Going by the legend, it appears the mosque will 500-600 from the WTC site...estimated.
FYI
4547 Park Place, -- HISTORY
During the September 11 attacks, the then-five-story building at 4547 Park Place,, between West Broadway and Church Street, was severely damaged. The building is located two blocks (less than 600 feet (180 meters)) north of the former World Trade Center.
That morning, the terrorists hijacked United Airlines Flight 175 as part of their attack on the World Trade Center Twin Towers. They crashed the plane into the South Tower at 9:03 a.m, triggering the destruction of the tower hours later.. The plane penetrated through the tower, and part of the plane's landing gear and fuselage came out the north side of the tower and crashed through the roof of 4547 Park Place, and through two of its floors. The plane parts destroyed three floor beams, and severely compromised the building's internal structure.
At the time, the building was leased to the Burlington Coat Factory.[7][28] Stephen Pomerantz owned the building, and his wife Kukiko Mitani, subsequently attempted to sell it for years, at one point asking for $18 million. Until its 2009 purchase, however, the building lay abandoned ..