What is this pipe in my sump pump hole?

[pwolke]

I have a ~25 year old house that has a sealed hole for what I'm assuming would be a sump pump. We're getting ready to finish our basement and want to put in a sump pump, but when I opened the cover to the hole, I notice half of a 4" pipe in there (see picture). Does anyone know what this is?

Additionally, when I open this hole, there's a negative draft (air pulling into the hole) and am just assuming that it might be related to a radon system that's already installed.

Does this pipe potentially go to a sewer line? What would a pipe be doing in this hole? Does anyone know what this is?

 

[Dlarrivee]

It could be an abandoned ejector basin, it could be a sump pit with an interior weeping tile tied into it, it could be radon related, it could be a "dry well"...

This is in the basement or outside?

 

[Sponsor]

 

[LLigetfa]

Can you follow the pipe with a snake and tell if it turns upward to vent through the roof? Maybe put a radio in the pit, turn it up loud, and go outside looking (listening) for the other end of it. Is that another smaller rusty pipe that the light is shining toward?

 

[pwolke]

Thank you for the quick responses and suggestions. Some more detail...

There is a working radon remediation system on the opposite corner of the basement. Hadn't given thought that this hole might be part of an older radon system.

The hole is inside (not outside). It's about 18" deep. The pipe (PVC, it looks like) is perpendicular to an exterior wall and seemingly leads outside underground. I will try snaking it and see if I run across any impass or turns. Will also try the suggestion of blaring a radio through it and see if I can hear it outside. In the picture, it DOES look like a small rusty pipe, but it's actually concrete and some dirt. Not sure if it's solid concrete on the bottom or not - something else I will find out. The hole is covered with a dark plexiglass, sealant on the edges where it meets the basement floor and a few holes on the top which are capped. The largest of the holes (about 4") is what I"m looking though with the camera to take the picture.

 

[Dlarrivee]

If the radio trick doesn't net any results, I'd be hiring someone with a scope to see where that leads...

 

[Reach4]

I would think it is from an outside perimeter foundation drain. If I am right, you must be on a well-drained hill, because there does not seem to be signs of water having been there.

If you are getting water seeping into the basement elsewhere, maybe that pipe was supposed to be to a perimeter drain, but it is not properly hooked up, or is maybe a fake.