One litter receptacle shall be provided for every 1,500 square feet of public plaza area, up to a maximum of 6,000 square feet. Plazas greater than 6,000 square feet in area must provide an additional litter receptacle for every additional 2,000 square feet of public plaza area. Public plazas that contain open air cafes or kiosks providing food service shall provide one additional litter receptacle for each 1,500 square feet of public plaza area occupied by such outdoor eating area. All litter receptacles must have a volume capacity of at least 25 gallons and shall be located in visible and convenient locations. All top or side openings must have a minimum dimension of 12 inches. Litter receptacles shall be provided within 50 feet of required seating areas in the public plaza.