The city of Bangor will soon change how residents dispose of their waste, eliminating the current program in which they separate recyclables — such as milk jugs and magazines — from the trash before it’s all left at the curbside for pickup. Instead, the City Council voted Monday night to move to a new program in which residents will mix their recyclables and trash into the same loads that are picked up from the curbside on a weekly basis. When the change takes effect in September, the loads will go to a new waste processing facility in Hampden that has been designed to automatically divert paper, plastic, organic material and other recyclable materials out of the waste stream.