Within thirty days after such a petition has been filed with the department it shall cause due notice to be given of a proposed hearing upon the question of the desirability and necessity, in the interest of the public health, safety and welfare, of the creation of such district, upon the question of the appropriate boundaries to be assigned to such district, upon the propriety of the petition and other proceedings taken under this chapter and upon all questions relevant to such inquiries. All owners and occupiers of land within the limits of the territory described in the petition and of the lands within the limits of the territory considered for addition to such described territory and all other interested parties shall have the right to attend such hearings and to be heard. If it shall appear upon the hearing that it may be desirable to include within the proposed district territory outside of the area within which due notice of the hearing has been given, the hearing shall be adjourned and due notice of a further shall be given throughout the entire area considered for inclusion in the district and such further hearing held.