I'm pretty sure it's live it was clean when the clay came off . The collar was clear and had never been mortared up .no photo as I didn't femember until everything was up to dpc. It was only when the inlaws started going on about aco drains and where they could go that I remembered . This I might dig down ,take a short length of pipe out and put a camera up and down it to see where it starts and finishes. I've only been trying to help out ,I'm on a site miles away . Worrying times .I don't want finish it , just for there to be problems later .also the pipe doesn't run under the super structure ,but that's beside the point I've got the spread on the concrete,and worry about anything washing into the pipe.thanks for replying