Some of the worst-maintained properties were found in Borough Park , Brooklyn , near tracks for the D and M trains , where investigators photographed rusty air conditioners leaning against a cracked retaining wall plastered with graffiti ; in Rockaway Park , Queens , by an area near the elevated A train where fencing , overpasses and sidewalks were severely damaged ; and in Pelham , in the Bronx , where piles of exposed refuse sat by elevated tracks for the 2,5 and 6 trains .