A recent article by Mark Vanhoenacker of Slate investigates the origins of the mysterious “Urban Gunk Accretions (UGAs)” that is found throughout the City’s underground stations.
Branko Kleva, assistant chief of the Division of Stations for NYC Transit, […] told me that what I call UGAs are what he calls tar or mastic […] used to seal and waterproof the tunnel structures. When the mastic warms up, especially in summer—either from the heat outdoors, or the heat that accumulates on subway platforms […] it can start to flow and drip down from the roof of the tunnel onto the platforms below.
While unappealing at first glance, there is a strange beauty that is found in these mastic drippings, one that Vanhoenacker points out in his article.
And if you look at UGAs closely and repeatedly, they began to take on a strange beauty, as if I was looking down at the surface of some distant volcanic planet from high above it, or indeed at a work of art.
Check out the full article for more on the origin of “Urban Gunk Accretions.”