Coincidentally to someone bringing one up earlier in another thread, there is one forming under a street in Santiago that I have seen. It is at the corner of Arturo Grullon and Ave. Metropolitana across the street from where HB's house is. There are already two holes in the pavement bigger than manholes and you can see from across the street that the ground is falling away from under the street. I don't know who to tell to get this fixed before the business on the corner falls into the hole or something.