WAC 296-826-30045   Installation.  

     You must:

     • Provide a minimum distance of five feet between aboveground and underground containers that have more than a twelve hundred gallon capacity each.

     • Protect containers from floating away, in areas with a potential for high flood waters, by providing either:

     – Secure anchorage;

     OR

     – Adequate pier height.

     • Follow Table 2 for aboveground, nonrefrigerated containers.


Table 2

Aboveground Nonrefrigerated Container Requirements
If you have: Then:
Aboveground containers Provide one of the following:
– Substantial reinforced concrete footings and foundations
  OR
– Structural steel supports mounted on reinforced concrete foundations.
Make sure the reinforced concrete foundation meets all of the following:
– Extends below the established frost line
– Is of sufficient width and thickness to support the total weight of the containers and contents
– Has the lowest point of the tank at least eighteen inches above the ground.
Make sure the footings meet all of the following:
– Extend below the established frost line
  – Are of sufficient width and thickness to support the total weight of the containers and contents.
Floating type foundations on containers installed aboveground Make sure they are designed to adequately support the tank, contents, and pumping equipment.
A horizontal, aboveground container Mount the container on a foundation that permits expansion and contraction.
Prevent the weight of excessive loads from resting on the supporting portion of the shell.
Provide saddle bearing that extends over at least one-third the circumference of the shell.
Prevent corrosion on the portions of the container in contact with the foundations or saddles.

     You must:

     • Follow Table 3 for underground, non-refrigerated containers.


Table 3

Underground Nonrefrigerated Container Requirements
If you have: Then:
Underground containers Set the containers on firm foundations or earth
– Surround containers with soft earth or sand well tamped into place.
Make sure the top of the container is at least one foot below the surface of the ground.
– If ground conditions make this impractical, use precautions to prevent physical damage to the container.
Exemption: It is not necessary to cover the portion of the container where a manhole and other connections are attached.
Securely anchor or weight containers when necessary to prevent floating.
Have a protective corrosion resistant coating applied before it is placed underground that is both of the following:
– Satisfactory to the authority having jurisdiction;
AND
– Equal to either hot dip galvanizing or two preliminary coatings of red lead followed by a heavy coating of coal tar or asphalt.
Lower containers onto firm foundations without damaging the protective corrosion resistant coating.




[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060. 06-10-067, § 296-826-30045, filed 5/2/06, effective 9/1/06.]