Viscous hydroplaning can occur at much lower speeds than dynamic....most likely on a smooth dirty surface.

The touch down areas of the runways will have a fair amount of rubber deposit left as aircraft land...modern airfields have a fairly rigorous runway cleaning program to remove it, but some airfields don't. Here, the first section of the runway could just be 'black rubber deposit'. This will show up very clearly on a concrete runway. Hence the question...viscous hydroplaning...smooth dirty surface...touch down areas of the runway.