Establishing the central iron range sanitary sewer district in the cities of Hibbing, Chisholm and Buhl and the townships of Kinney, Balkan and Great Scott and the territory occupied by Ironwood to be under the control and management of the central iron range sanitary sewer board, specifying board membership requirements and certain general and sewage collection and disposal powers and providing for organization and operation; requiring and providing for the board to adopt a comprehensive plan for the collection, treatment and disposal of sewage, specifying certain plan and public hearing requirements; granting the board certain obligations issuance, special assessment imposition and property tax levying authority; providing for the expansion of the system; requiring and providing for the board to annually prepare and adopt a budget; providing for the allocation of costs; requiring and providing for public hearings on specific projects; requiring board designation of depositories; providing for funds, accounts and investments; authorizing certain service and construction contracts; exempting board property from the property tax(ra)