Another observation
When I first saw it, I thought the large square to the west of one of the "patterns" was a digital artifact. 40.457921,93.369952
If you look closely it's an area 2600' x 2800' and it's level to with 50' feet. You can see the slopes where sections were filled. Cant tell if it was made before the chalk line pattern because photos were not available.
Another interesting feature is located at 40.491067,93.468700 This square does appear to be a target littered with bomb craters. There are also three weapons bunkers surrounding it.
Another interesting thing about this is the area is covered by tarps or fabric in the 2005 photo and the bunkers were not built yet.