eblackwelder, A thread HERE
from last winter explains it. The incidents were unrelated, but had a big cumulative effect on the psychy.
Bill, There is no doubt been a lot of training put in to prevent future tragedies, and of course the tragedy itself was something everyone learned from. In this case, when a patroller fell in, the first fatality was assured, when two would-be rescuers were also killed, it became a classic accident scenario that might be preventable through training. Similar accidents have ocurred with utility workers, police, and firemen who have witnessed a co-worker fall in a pit or tunnel, then the rescuer also succums. This is a scenario most rescue workers are trained in. The combined hazard of CO2 and confined space is well known, but I suspect not recognized. This fumerole was always fenced off to keep someone from falling in. Nothing is more dangerous than the hazard you see everyday. The fumerole at Mammoth is relatively harmless as long as it is open to the air. It was the deep snowpack which allowed the heavier than air CO2 to accumulate to lethal levels, changing something seen everyday from a curiosity to a deadly trap.
I'm sure they will expand the perimeter of the closed area and enhance signs in the area. Of course now that everyone knows what can happen, it is very unlike to recur.