DIY

Hey, I've got a cold room in my place that is concrete on all sides, I'm going to be framing it in and insulating and I don't really need any help there unless there's anything cold room specific I should know, however.

As you can see I have a floor that appears to be a stepped concrete pit, filled with quite a lot of dirt, and what I believe is probably a tie in to the sewage drain.

Can I just get rid of the dirt? The whole room spells like petrichor because of it.

Assuming the pit continues to step down, can I just build the floor over it regardless, and do I need to support the pipe in some way if the dirt is removed?

Or, if I'm completely off base please let me know what I should be doing.

Thanks