As used in this part, the following definitions apply:
(1) "Closure" means the permanent shutting down of operations at a workplace.
(2) "Department" means the department of labor and industry.
(3) "Employer" means the state of Montana.
(4) "Governmental facility" means any institution, department, agency, bureau, or office operated by the state of Montana and employing more than 25 persons.
(5) "Retrenchment" means reducing the number of employees at the governmental facility by at least 250 employees over any 2-year period, provided that a reduction in the number of employees by attrition is not retrenchment.