I was going to redo my images and upload them again (I usually resize to 800px wide and this board likes 500px wide.) I'll do that for future posts because my markings are too small on the existing one if I do that.
There are a few more orange markers that I don't have in my drawing but I neglected to print out a google map before I went there. By the time I got home, I forgot the location of a couple of them.

With that being said, I don't think those are for supports for any coaster but are survey stakes that will be used for upcoming ground work. My speculation is that this is phase 1 of a larger plan which includes putting the infrastructure in place for a park expansion, reworking the access parking for future plans, the on-site hotel we all are pretty sure that is coming, etc.
I heard some rumors while I was there and I also talked to an engineer who was working around the perimeter of the bus parking lot. I'm not big on rumors so I'll keep them to myself. However, the engineer was there because it was raining and he was evaluating how groundwater was draining on the property. He said the blueprints he was carrying would be of no interest to me.
