Adequate facilities shall be provided for the handling of garbage and trash by the installation of a raised platform, a minimum of three inches from ground level for each garden apartment building, which platform shall be enclosed or walled in with the same brick or stone material as used on the main buildings. All garbage and waste receptacles shall be stored and maintained on the platform, and there shall be a minimum capacity of 40 gallons per dwelling unit. The height of the wall or enclosure shall be at least the height of the garbage or waste receptacle.