Ayisha
Contributor
What I cannot get my head around is a student with an instructor for a training dive at a 15-20' deep quarry ends up on the bottom, is unable to save themselves for whatever reason, and the instructor either cannot or will not rescue them...
It seems that's where #21 comes in, "dangerously murky water that reduced visibility".
When the victim sank, the instructor may not have been able to see or locate her down below until it was too late.