Existing ground needs to be encased in concrete.

[ROHM]

I have an existing ground that attaches to the cable tray and goes to the ground grid underneath the concrete foundation. Please see attached photo with the ground in question circled in red. The concrete slab that will be poured to seperate the containments will encase the ground wire to the heigh marked in yellow. My question is whether I can have the existing ground stay where it is and have concreted poured up to the yellow height or do I have to remove it and relocate it?

What does the NEC say about ground wires (insulated) in concrete?

 

[don_resqcapt19]

Since the code permits concrete encased electrodes made of bare copper in concrete, I don't see an issue. I don't think the code specifically addresses this issue.
If the grounding conductor in question is a GEC, what type of conduit it is in now, when drops down from the tray?

 

[ROHM]

The ground is just grounding the cable tray metal itself. The ground is not a wire coming from in the cable tray. The ground wire is a THW 2/0 AWG insulated cable. Does the fact that it is not bare copper and insulated ground wire make a difference?

 

[rc/retired]

Does the fact that it is not bare copper and insulated ground wire make a difference?

Nope

Ron