What's this pipe for in foundation?

[Brody Reb]

What's the purpose of this black pipe for the ground plumbing? It was about 5.5" diameter.

 

[John Gayewski]

Looks like protection for a cleanout riser. There's not enough info to know for sure.

 

[Sponsor]

 

[Tuttles Revenge]

Could be a backwater valve with a riser sleeve