23rd Ward Ald. Mike Zalewski made a surprise announcement Monday – after 42 years working with the city, he would be stepping down at the end of May, opting not to finish his term. He has been serving as alderman in the Southwest Side ward since 1995, as committeeman since 2005, and as chair of the Aviation Committee since 2011. He got his start as a city garbage man and rose to deputy commissioner for the Department of Streets and Sanitation under Mayor Richard M. Daley, later becoming Daley’s president pro tempore.