Filling in large hole in soil

So I've got a large hole roughly 2m wide and about half a meter deep, I need to pour a concrete slab above it for some brick steps.

It was filled with big chunks of uncompacted clay soil from a foundation repair job, but I've removed them as I don't think they're stable enough, there were many gaps in them.

So what can I use to fill it up that's stable enough? normal soil? compacted roadbase?





Read the full thread at RenovateForum.com...