Does UE4 use Bounding Volume Hierarchy to organize objects?

Hi,

When searching in Engine source code I found that bounding volumes are mentioned only in kDOP tree (TkDOPNode). It’s important for me to know because I want to make sure that hierarchical complexity is well organized. How does UE4 handle actors that are positioned close to each other? Are they grouped? Is scene organized the same way as editor shows? E.g. if I have flat tree it will be flat inside engine and all rendering algorithms will traverse this flat structure without using hierarchy? Hierarchy is important for example for frustum culling, occlusion culling to send occlusion queries for groups of objects.

I was wondering this myself.
I don’t think it uses it directly but I am wondering if there’s a way to enable it.
If there isn’t then it might be we have to create our own, which seems odd to not be included in such a powerful engine.