Good morning tom-cast iron it is-don't think it would be clay. But what to I know. I didn't see it when thwy were putting it in so I don't know what was there-i do know there was no digging so I kind of believe the guy who looked at it yesterday. He pulled at least 5 lbs of fine wadded up roots out of there in one big line-no big ones. This is not a good time for me to have to put out 2,500 but as I said-don't want a broken sewer line in the winter and delay in repairing will jusy make it worse. I will call and set up 2 more estimates this week and then repair it. I was reading about trenchless repair which won't require digging up of the concrete but I imagine that will be big bucks
Will keep you posted
P