NFPA 58, section 3.2.4.2-- "LP Gas containers or systems of which they are a part shall be protected from damage from vehicles."

Also, ASME containers must be at least 10 ft. from the property line except if >500 gal. w.c., they must be 25 ft. Buried ASME tanks Min. 10 ft. from lot lines.

No setbacks listed for DOT cylinders. However, you still must meet the clearance to windows etc. A tank at the roadside would have a 0 clearance to a source of ignition (cigarette), and thus not allowed. Also, the place where filled must not put the operator in danger. What about the ground? Is it sloped to shed gas or allow collection? That retaining wall will tend to hold gas against the base of the tank, which is a no-no. The base of the tank must be sloped or not have anything that would tend to allow gas to accumulate such as bushes, raised beds, etc. This LP company was nuts to install a tank here.

For your reports, I recommend you look in the tank and determine whether DOT cylinder or ASME container and the water capacity, which are needed to determine such clearances.

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