(1) This chapter applies to all prefabricated tanks and all cast-in-place tanks. This chapter establishes sewage tank design and construction requirements, plan review and approval requirements, and prefabricated tank registration requirements.

(2) This chapter contains specific requirements for:

(a) Manufacturers of prefabricated tanks and builders of cast-in-place tanks;

(b) Persons designing sewage tanks;

(c) The department for reviewing, registering, and approving sewage tank design and construction plans;

(d) Persons installing sewage tanks; and

(e) The local health officer and the department for approving on-site sewage system designs, plans, specifications, and installations under chapters 246-272A and 246-272B WAC.

(3) This chapter does not contain all requirements for on-site sewage systems. Additional requirements for on-site sewage systems, including maintenance requirements, are found in chapters 246-272A and 246-272B WAC.

(4) This chapter does not apply to:

(a) Facilities regulated by the department of ecology;

(b) Reclaimed water systems as described in chapter 90.46 RCW;

(c) Tanks used to store municipal sewage sludge regulated as biosolids under chapter 173-308 WAC; or

(d) Geomembrane containment vessels for public domain treatment technologies. An example of this excluded technology is PVC containment vessels for public domain packed bed filters.