5706.4.14 Valves.

All inlet and outlet nozzles of tanks shall be provided with a valve of steel construction of a 150 pounds per square inch (psig) (1034 kPa) rating located as close as practicable to the tank.

5706.4.15 Dike construction.

All dike walls shall be of steel or reinforced concrete, designed to be liquid-tight and to withstand a full hydraulic head, and constructed so as to afford ready access. Where stairways or other similar means are required to afford such access, they shall be constructed of steel or other approved noncombustible material.

5706.4.16 Dike capacity.

Each single dike wall enclosure shall have a capacity equal to 110 percent of the tank's capacity. Tanks arranged in groups with a total capacity not exceeding 500,000 gallons (1 892 500 L) may be enclosed in a single dike wall enclosure. Each group tank dike area shall have a net capacity not less than that of the largest tank plus 10 percent of the aggregate capacity of all other tanks served by the dike enclosure. That portion of the surface occupied by tank or tanks shall be included when computing the diked area.

5706.4.17 Tank and piping test.

Tank and piping shall be tested at the time of installation at the owner's risk by his or her representative before a representative of the department as follows:

   1.   Aboveground, underground and mounded-over tanks shall be filled to capacity with water and maintained for not less than 24 hours.

   2.   Piping shall be hydrostatically tested to a pressure of 100 pounds per square inch (psig) (689.5 kPa) or 150 percent of the maximum operating pressure, whichever is greater, for 30 minutes.