No, literally. The Post reports that employees at the U.S. Post Office at 2 Massachusetts Avenue NE are suffering from a leak located somewhere in the undercarriage of the old building which is causing brown stains on the ceiling and an overwhelming sewage scent. Yummy! Not content with attempting to overthrow one of the District’s busiest postal centers, the gaseous amalgam of odor is also attacking the Capitol City Brewing Company, also located in the…