In the case of outdoor storage establishments erected or created after the date of enactment of this chapter, the entire perimeter of the lot upon which such outdoor storage establishment is located shall contain a five-foot-wide buffer area within which there shall be either trees or fencing or a combination of same, as determined by the Planning Board pursuant to its site plan review powers, in order to obscure such storage area from the view of adjoining property. Such buffer area shall be maintained in the same manner as buffer areas within the Business B District generally. Where other provisions of this chapter require buffer areas in excess of five feet in width, such other provisions, if applicable, shall take precedence over the foregoing. In cases where a buffer area adjoins the street line of any premises, vehicular driveways for ingress and egress shall be permitted, provided that the total width of such driveways shall not be greater than 30% of the street line. The location of such driveways shall be determined by the Planning Board during site plan review of the premises.