As used in ORS 454.430 to 454.445:
(1) “Assessment” includes all costs, fees or other charges for the construction of or connection to sewage treatment works that are eligible for installment payments under ORS 223.205 to 223.775.
(2) “Commission” means the Environmental Quality Commission.
(3) “Department” means the Department of Environmental Quality.
(4) “Extreme financial hardship” has the meaning given within the assessment deferral programs adopted by public agencies and approved by the Department of Environmental Quality.
(5) “Public agency” means any state agency, incorporated city, county, sanitary authority, county service district, sanitary district, metropolitan service district or other special district authorized to construct water pollution control facilities.
(6) “Treatment works” means a sewage collection system.