Within the South Street Seaport Subdistrict, the City Planning Commission may modify, by special permit, the height and setback and lot coverage regulations of Section 91-30, provided that:
(a) either of the following conditions have been met:
(1) that the developer has obtained negative easements limiting the height of future development or enlargement to 85 feet or less on any adjoining zoning lots which are contiguous or would be contiguous to said zoning lot but for their separation by a street or street intersection, and such easements are recorded against such adjoining zoning lots by deed or written instrument. The Commission shall consider the aggregated areas of said zoning lot and the adjoining lots subject to such negative easements and the extent to which they achieve future assurance of light and air in determining the maximum permitted coverage. In no event shall such coverage exceed 80 percent of the zoning lot on which the development or enlargement will be located; or
(2) that the lot coverage for that portion of a development or enlargement below 300 feet may be increased to a maximum of 80 percent when additional development rights have been purchased and converted to increased lot coverage. The maximum percentage of lot coverage on such receiving lot shall be the sum of 65 percent plus one-half of one percent for every .10 by which the total floor area ratio on such receiving lot would exceed a floor area ratio of 21.6, provided that the development or enlargement on such receiving lot has achieved a minimum floor area ratio of 18.0;
(b) In order to grant such special permit, the Commission shall make the following findings:
(1) the location of the development or enlargement and the distribution of bulk will permit adequate light and air to surrounding streets and properties;
(2) any modification of height and setback will provide for better distribution of bulk on the zoning lot; and
(3) such special permit will aid in achieving the general purposes and intent of the Subdistrict.
The Commission may prescribe appropriate conditions and safeguards to minimize adverse effects on the character of the surrounding area.