I'm sitting in the bleechers for this one, just wanted to add this to the conversation...I'm going back up now!
SR
So, How big do you think it would be?
If it was bigger than the lander, the lander would have fallen into it. It didn't do that or they would not have been able to take off again.
They set up a tv camera that stayed there and caught the take off of the luner module. The lander was standing level over what would be the "blast crater". The bottom part is still there.