The Zoning Board of Appeals shall determine, after requesting and receiving within 30 days a report from the Planning Board, whether a use not specifically listed as a permitted use in any zoning district of the City is appropriate in the district where such use is proposed. In making such determination the Zoning Board of Appeals shall consider the stated purpose of the zoning district and whether the proposed use is substantially similar in size, density, operations, impacts and other characteristics of uses permitted in the district. If the proposed unlisted use is found to be similar to uses specifically listed and appropriate in the district, the Zoning Board of Appeals shall pass a resolution to treat the proposed use as a permitted use in the district.