^ True story.
We had a bunch of dump truck loads of gravel and top soil driving on the second (unpaved) driveway and it made a bit of a mess. Tore up the driveway (ruts that filled with water for over a year), possibly broke the natural gas line to the shop, and broke our sump pump line from the basement.
I could argue the latter two weren't buried deep enough, but it was the dump trucks going on it that caused problems. I remember they said they didn't want to drive on our asphalt driveway; said it was too thin and they'd smush it. Said they'd smush the unpaved drive too (the ruts), but we didn't care 'bout that - didn't realize how shallow the NG and sump pipes were until after the damage was done though.