Research what. It is just a bad pour when the foundation was laid. How old is this place that we are talking about? The whole pour looks like they did not vibrate or agitate the mix during the pour to help compact it down in the forms, to push the bubbles out.
__________________ Ren: Now listen, Cadet. I've got a job for you. See this button? Ren: Don't touch it! It's the History Eraser button, you fool! Stimpy: So what'll happen? Ren: That's just it. We don't know. Maybe something bad, maybe something good. I guess we'll never know, 'cause you're going to guard it. You won't touch it, will you?