Partial tunnel collapse at Snowy 2.0 construction site raises fresh safety concerns, page-5

I remember years ago when Snowy 2.0 was such a cheap project spruiked by PM Turnbull -
a media report was published (can anybody find a link??)
and it had a reference to their expectations for tunneling to encounter "five rock types".
I remember my shock at reading that and how could professionals state such rubbish.
More like 50 rock types for a start.