Section 75.1905-1 - Diesel fuel piping systems(a) Diesel fuel piping systems from the surface must be designed and operated as dry systems, unless an automatic shutdown is incorporated that prevents accidental loss or spillage of fuel and that activates an alarm system.(b) All piping, valves and fittings must be- (1) Capable of withstanding working pressures and stresses;(2) Capable of withstanding four times the static pressures;(3) Compatible with diesel fuel; and(4) Maintained in a manner that prevents leakage.(c) Pipelines must have manual shutoff valves installed at the surface filling point, and at the underground discharge point.(d) If diesel fuel lines are not buried in the ground sufficiently to protect them from damage, shutoff valves must be located every 300 feet.(e) Shutoff valves must be installed at each branch line where the branch line joins the main line.(f) An automatic means must be provided to prevent unintentional transfer of diesel fuel from the surface into the permanent underground diesel fuel storage facility.(g) Diesel fuel piping systems from the surface shall only be used to transport diesel fuel directly to stationary tanks or diesel fuel transportation units in a permanent underground diesel fuel storage facility.(h) The diesel fuel piping system must not be located in a borehole with electric power cables.(i) Diesel fuel piping systems located in entries must not be located on the same side of the entry as electric cables or power lines. Where it is necessary for piping systems to cross electric cables or power lines, guarding must be provided to prevent severed electrical cables or power lines near broken fuel lines.(j) Diesel fuel piping systems must be protected and located to prevent physical damage.