Underground metal pipe feeding an underground pool losing @ 100 gl/day. How to fix without replacing the pipes?

Does this pipe fill the pool directly or is it tapped into your filter system? Got and really wet spots around the pool? Once you locate the leak and inspect the pipes then you can decide to replace or try to patch, not before

My problem is with the pipes that feed the pool from the filter and them return the water from the pool to the filter. They are buried underneath the concrete slab [3 inches thick and 6 feet wide] around the pool. Every other variable [liner, joints, outlets] I had already tested and discarded.

I don't see a way around breaking the concrete and digging up the pipe. Then again I am not on site so I can't be sure.