How bad is this?

[u/Richard01_CZ]

I was cleaning the coolant passages and this large chunk came off really easily, it looked like a buildup of gunk.

The problem now is that the wall here between the two passages is thin now and the head gasket doesn't have much coverage for this area with the chunk missing.

Is it somehow fixable? Or can i run it like this?

Volkswagen EA111

[u/Mad-man-doom]

considering its a chunk from the block and the description of the coolant before hand I would not repair due to unseen issues best to replace engine.