When the rest of the garage floor sank, these pipes evidently supported the corner. Looks like an abandoned heating oil tank fill and vent to me (almost everything in this area is NG now). Any other options?
What the heck, a guess a picture would help!
Not typical for the fill and vent to be in a garage, but anything is possible. It does resemble them though.
It almost looks like the garage was built on top of it, but you never know. I’m going to report that it is likely an oil tank and recommend further evaluation.
Just for kicks, I found this in a basement a while ago.