As used in this chapter:

(1) "Applicant" shall mean that municipality applying to the department for authority to administer the permit program pursuant to RCW 90.48.165.

(2) "Application for authorization" shall mean that application submitted by a municipality seeking permit-issuing authority pursuant to RCW 90.48.165.

(3) "Application to discharge" shall mean that information required from a discharger in acquiring a permit to discharge commercial and industrial wastes into a municipal sewerage system.

(4) "Commercial and industrial wastes" shall mean the wastes, whether solid or liquid, from any commercial or industrial operation, other than domestic sewage.

(5) "Department" shall mean the department of ecology.

(6) "Discharge" shall mean any commercial or industrial operation which results in the disposal of solid or liquid waste material into a sewerage system operated by a municipality which discharges into the public waters of the state.

(7) "Enforcement action" shall mean any administrative or judicial action initiated to achieve compliance with the conditions of a discharge permit, regulations of the department, and water pollution control laws of this state or of the federal government.

(8) "Municipality" shall mean any city, town, or municipal corporation established according to the applicable laws of this state.

(9) "Permit" shall mean the official authorization to dispose of commercial and industrial wastes into waters, to include all regulatory constraints and conditions described therein, issued to a discharger.

(10) "Permit program" shall mean the process of granting or denying by municipalities, authorized as herein provided, of approval of applications to discharge into the sewerage system of such municipalities, the monitoring and inspection of dischargers, and the taking of appropriate enforcement action.

(11) "Sewerage system" shall mean any system operated by a municipality for the collection, transfer, treatment, and disposal of sewage.