There is a law in the USA requiring

 that you call for underground utility locations

 before you do any excavation.

 

The pictures below are a result of a farmer using

 a post hole digger without calling for "locates"

 and he hit an underground, high-pressure cross

 country gas pipe.

 

Had to be one of those gas powered augers, either free-standing or on a tractor.

 

They never did find the guy...

 

 It took out 2 homes...