Details on Green Line retaining walls and noise barriers Post published:May 30, 2012 Post category:Green Line MassDOT has posted its presentation on retaining walls and noise barriers, from the May 22 public hearing. You Might Also Like Boston Globe: Transportation report delayed April 23, 2006 State Transportation Plan leaves out Green Line March 10, 2005 A graphic that says it all October 29, 2015