A unit of local government may enter into intergovernmental agreements to prepare and implement solid waste management plans, and may adopt those procedures for the preparation and implementation of plans the contracting parties deem appropriate. A unit of local government may delegate any power to another unit of local government for the specific purpose of preparing and implementing a solid waste management plan. However, no plan prepared pursuant to an intergovernmental agreement under the authority of this Section shall provide for the siting of a new pollution control facility within the incorporated area of any municipality or the unincorporated area of any county which is not a signatory to the agreement without the consent of the municipality or county.
     It is the intent of the General Assembly that any action taken pursuant to this Act by one or more units of local government, acting individually or jointly, shall be deemed to be State action for purposes of the application of federal antitrust law, and no such action shall be prohibited by virtue of any anticompetitive effect it may produce.