2024/08/07 08:50 Bergland. Water has a dark greyish black discolouration.  Strongish smell present close to the river. No foam, but lots of gassing and some floating black clumps. Someone has rearranged the rocks in the river and moved some onto the bank.  The ones from the river are all black.  I’ve included a closeup of one of the smaller rocks.

In this photo one can see what looks like oil flakes, as well as gassing and black clumps.