I'm guessing "micro breaches" refers to hydrogen-induced cracks. Media likes to talk about it in bigly, threatening terms such as "THOUSANDS OF CRACKS FOUND IN REACTOR VESSEL" - of course anyone with half a brain starts to wonder "aren't these PWRs?". Much like people like to write headlines such as "HUNDREDS OF NUCLEAR INCIDENTS AT NPP XYZ", where "nuclear incident" means "reported event", which includes such dramatic incidents as "a backup valve in some secondary circuit had to be replaced because it was stuck" or "a bird flew into the transformer, tripping protection and taking a block offline".