In designing projects to be permitted under this section, a sufficient area must be provided to accommodate the use in keeping with the character of said use and in using appropriate design standards; however, the lot shall contain an area of at least 10 acres. In the event that it can be demonstrated that the proposed project can meet all of the other criteria necessary for the issuance of a permit on a lot containing less than 10 acres in area, the board may reduce the lot area requirement but in no event, reduce it less than the minimum lot size for the zone district in which the property is located.