The legislature finds that:

(1) Protection of the environment and public health requires properly designed, operated, and maintained on-site sewage systems. Failure of those systems can pose certain health and environmental hazards if sewage leaks above ground or if untreated sewage reaches surface or groundwater.

(2) Chapter 70A.110 RCW provides a framework for ongoing management of on-site sewage systems located in marine recovery areas and regulated by local health jurisdictions under state board of health rules. This chapter will provide a framework for comprehensive management of large on-site sewage systems statewide.

(3) The primary purpose of this chapter is to establish, in a single state agency, comprehensive regulation of the design, operation, and maintenance of large on-site sewage systems, and their operators, that provides both public health and environmental protection. To accomplish these purposes, this chapter provides for:

(a) The permitting and continuing oversight of large on-site sewage systems;

(b) The establishment by the department of standards and rules for the siting, design, construction, installation, operation, maintenance, and repair of large on-site sewage systems; and

(c) The enforcement by the department of the standards and rules established under this chapter.