Providing for the submission to the qualified electors of the City of Philadelphia of an amendment to the Philadelphia Home Rule Charter, authorizing City Council to provide, by ordinance, for bid preferences on City contracts either for bidders offering environmentally preferable products or services or for businesses whose products, services and operations demonstrate a high level of environmental stewardship; fixing the date of a special election for such purpose; prescribing the form of ballot questions to be voted on; and authorizing the appropriate officers to publish notice and to make — Open Common Ground