49 CFR 193.2155
Structural requirements.
(a)The structural members of an impoundment system must be designed and constructed to prevent impairment of the system's performance reliability and structural integrity as a result of the following:#
(1)The imposed loading from—#
(i)Full hydrostatic head of impounded LNG;#
(ii)Hydrodynamic action, including the effect of any material injected into the system for spill control;#
(iii)The impingement of the trajectory of an LNG jet discharged at any predictable angle; and#
(iv)Anticipated hydraulic forces from a credible opening in the component or item served, assuming that the discharge pressure equals design pressure.#
(2)The erosive action from a spill, including jetting of spilling LNG, and any other anticipated erosive action including surface water runoff, ice formation, dislodgement of ice formation, and snow removal.#
(3)The effect of the temperature, any thermal gradient, and any other anticipated degradation resulting from sudden or localized contact with LNG.#
(4)Exposure to fire from impounded LNG or from sources other than impounded LNG.#
(5)If applicable, the potential impact and loading on the dike due to—#
(i)Collapse of the component or item served or adjacent components; and#
(ii)If the LNG facility adjoins the right-of-way of any highway or railroad, collision by or explosion of a train, tank car, or tank truck that could reasonably be expected to cause the most severe loading.#
(b)An LNG storage tank must not be located within a horizontal distance of one mile (1.6 km) from the ends, or 1/4 mile (0.4 km) from the nearest point of a runway, whichever is longer. The height of LNG structures in the vicinity of an airport must also comply with Federal Aviation Administration requirements in 14 CFR Section 1.1.#