At the hearing provided for in § 30.24, the Council shall review the roll and may confirm it with such corrections as may have been made, if any, or may refer it back to the Assessor for revision or may vote to abandon any further proceedings in connection therewith. If, at or prior to the hearing on the confirmation of any special assessment roll written objections to such special assessments are made by the owners of property which will bear 50% of the cost of the proposed construction or improvement, the same shall not be made and the special assessment roll shall not be confirmed unless approved by at least four of the members elect of the Village Council. After the confirmation, the special assessment roll and all assessments shall be final and conclusive unless attacked in a court of competent jurisdiction within 30 days after the date of confirmation.
(O.C. § 1.41)