Thanks PoolDoc,
I isolated suction lines, return lines, and liner yesterday with the pump off. The water level seemed to stabilize when I shut the return lines in the shallow end located at the entry steps, so I think the biggest leak is there. For now I have shut them off and blocked the jets, and only running the 2 return lines on the side of the pool. I found another leak in the PVC connection from pump to pipe, so I'm going to attempt and replace that today.
My question is do you think it would be ok to run just the 2 return lines this season and try to fix the issue this fall ? Looks as if the lines are run about 30ft. under concrete