So I've been looking at various resources in order to beef-up my descriptions for the FDA. Via Robin's suggestion, I came across the DSNY's Annual Reports. They're quite helpful in getting a sense of the scope of activities the DSNY participates in.
For example, on page 11 of the 2006 report, there's discussion of the Lot Cleaning Division, which manages the Neighborhood Vacant Lot Clean-up Program. Basically the program does just what it says: it tidies derelict areas (both public and private). I had no idea the DSNY did such things. (This is of particular interest to me since in my ethnography I discussed such areas as if no one ever cleaned them. Not the case -- if one lobbies enough or the space becomes overrun with rodents or mosquitos, DSNY will come.)