There's a homeless guy who lives in the tunnel/end of the platform at Broadway. I have heard people reporting he was burning paper down there last Sunday, but apparently nothing was done about it.

Yesterday I came through the station and got off the train at Broadway at 5:30ish PM, and it was definitely a paper/wood smoke smell and definitely not an electrical/oil/rubber smell. My guess is that he decided to cook supper down there and the T's too embarassed to admit it.