24.321.312 STORAGE TANKS
(1) Propane tanks and other flammable or combustible liquids storage shall be buried underground. If soil or subsoil conditions prohibit complete burial, then tanks shall be partially covered by at least one foot of earth, sand, or other noncombustible material.
(2) Other installation methods such as installation in vaults or other protective methods that comply with NFPA 30 and NFPA 58 standards may be used in lieu of burial.
(3) Structures not located in a designated WUI may have storage tanks installed above ground, so long as they conform to the NFPA 58 standard and be located at least 30 feet from any structure.