
I'm not going to close as duplicate until it's certain. Update: This is probably related to #42, since Driller Night and Explosive Action both also have a collapsing wall at the beginning of the level.

It happens randomly, and Chief's landslide announcement is extremely rare. It does not seem to happen in levels that start with Chief announcing something. It most commonly happens in Breathless, but has also been heard in Erode Works, Lake of Fire, Hot Stuff, and Rocky Horror. It appears to function separately from #42. However, what levels it happens in, if any, seems random. When encountered in a level, it will always play at the start of the level no matter how many times the level is restarted. Very rarely, Chief's landslide announcement will play as well, despite no landslide notification appearing. Sometimes when starting the level, the sound of a wall collapsing will play, despite there being no collapsing wall nearby. Video Example of placing the Mining Laser and deciding on the building rotation. Screenshot Example of placing a larger building with the arrow visible.

It's not too hard to figure out if you're familiar with how the rotation works, but it would be more user-friendly to show an arrow so that it's easy to tell. When placing buildings like the Mining Laser or Geological Center, there isn't any indicator for what rotation they'll spawn in.
