If the land involved in any appeal is within 500 feet of the boundary of any other municipality, or any existing or proposed county or state park or other recreation area, or the right-of-way of any existing or proposed county or state parkway, thruway, expressway, road or highway, or the existing or proposed right-of-way of any stream or drainage channel owned by the county or for which the county has established channel lines, or the existing or proposed boundary of any county- or state-owned land on which a public building or institution is situated, then notice of the public hearing and description of the applicant's proposal shall be mailed to the Orange County Planning Department.