Warning signs

While I stayed in an apartment in Battery Park City, I walked past the Ground Zero site almost everyday for a week or so and would see people photographing anything and everything that they could, pointing their cameras into the construction site.
I wanted to capture something that most people probably didn't even notice or see, that conveyed something of the loss without being obvious. Almost like a ghost or the fading of something solid that was once there, these signs on the hoarding really conveyed this to me.