It's that, and the tower's concrete base (which is huge, and virtually indestructible, which means no-one is going to remove it. It'll stay in the ground forever, essentially sealing it (even if there is a meter of dirt covering it). See [1] for a picture to understand the dimensions:

[1] https://www.sserenewables.com/news-and-views/2021/09/concret...