Digging Up The Dead
This is a creepy discovery. Imagine finding a coffin on your friend’s farm. They might believe they were living on top of a graveyard, or there was a horrible crime committed on their property. They decided to keep it closed before they knew what it was, which was probably a smart move.
But it turns out it’s a septic tank. That’s not as creepy as a coffin. If the original poster kept digging, they would have found a pipe on either side. These tanks were usually buried between one and three feet below the ground (via Everyday Monkey).