Whenever the property line of a lot in the B-4 Zone abuts or is directly across a street from a residential use or zone, a buffer zone of at least 100 feet in width shall be established in accordance with the provisions of §
245-409. Whenever the property line of a lot in the B-4 Zone shall be adjacent to a residentially zoned lot or use, a buffer zone of at least 150 feet shall be established. The buffer zone may be increased, depending upon the character and intensity of the proposed use.