Institutional and industrial uses that predate enactment of zoning in 1959 and which have become legally nonconforming may be expanded by conditional use approval up to 50% of the building or floor area, whichever is less, existent as of the date the herein subsection is enacted (for the duration of the life of the nonconformity), provided that the resulting impervious surface ratio does not exceed the permissible impervious surface ratio in the underlying zoning district. Strict proof of eligibility under this subsection shall be provided as part of the conditional use application and shall be included in the applicant's burden of proof at the conditional use hearing. Any expansion approved pursuant to this subsection shall comply with all criteria set forth in §
160-62B(2). Nonconforming uses qualifying under this subsection may expand onto another parcel(s) of land subsequently added to the original parcel, provided that the use still complies with all the criteria set forth in §
160-62B(2) and the added parcel is consolidated with the original parcel. Alternatively, if such parcels cannot be consolidated, then expansion as set forth above may still occur, provided that the landowner agrees, in writing, to place a restrictive covenant on the additional parcel whereby the expanded use shall cease and desist on that parcel if the parcel is sold to another party. This §
160-62B(4) shall not apply to rifle ranges (C6 use), correctional facilities and group institutions (C16 use), quarries (H4 use), resource recovery facilities (H5 use), auto salvage (H6 use), junkyards (H7 use), composting facilities (H8 use) and outdoor storage (H9 use).