Hatches not showing as buried objects ( and taking up two tiles ).

Hatches aren't showing up as buried objects in a sense that the information panel suggests - they seem more like a random encounter, with the exception of the starting template - this contains a hatch, it's always in the same place. I assume they're supposed to show as a cracked tile prior to being discovered - instead they don't, and mousing around can net you a hatch location - this description below shows up on their tile and the mound above them.