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The Sunshine Mine Disaster: A case study for emergency response. Sunshine Mine - Kellogg, Idaho. Largest & richest silver mine in US. On the morning of May 2, 1972, the mine manager & superintendent away attending shareholder’s meeting. 7:00. 173 men began work. The Path Inside. 11:30.
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The Sunshine Mine Disaster: A case study for emergency response
Sunshine Mine - Kellogg, Idaho Largest & richest silver mine in US
On the morning of May 2, 1972, the mine manager & superintendent away attending shareholder’s meeting
7:00 173 men began work
11:30 Electricians at electric shop on 3700 level, smelled smoke, & shouted a warning
Foreman’s Office “Blue Room”
11:40 They reported smoke to Foremen Harvey Dionne & Gene Johnson who were eating in “Blue Room”
The foremen traveled down to the 910 raise to find source of smoke They found smoke, but no fire
When CO detected, fire doors automatically closed & miners were to travel to #10 shaft to ride “Chippy Hoist” out
20 MINUTES Foremen delayed evacuation for 20 minutes looking for fire
12:00 Foremen Gene Johnson called for evacuation of mine Word spread there was a fire & they were to evacuate
12:05 4400 level crew called for “Chippy Hoist” when they saw smoke in shaft - no response from hoist room
12:05 The safety engineer went to compressor room & activated stench warning system The “STENCH” would take 26 minutes to reach all areas
12:05 “Chippy” operator station was overcome by smoke Double-drum hoist operator told to prepare to lift people with production hoist He was still running production & had not heard of fire
Most workers aware of fire when smoke entered their workplaces Men dispatched to relay verbal warnings to others in remote locations Within a short time of detecting smoke, most workers went to #10 shaft station
The main “double drum” hoist not designed to move men A smaller 12-man car was quickly put in place The small lift made operation very slow
12:10 Men hoisted to 3100 level & directed to walk one mile out to Jewell Shaft
Most had never been to 3100 level before Normal path out was to ride motor down on 3700 which was full of smoke
Gene Johnson determined intense smoke resulted from short circuit in ventilation system & now making things worse He sent 2 miners to wait by fans & he would give signal to stop fans 12:30
Ventilation Plan Bad Air Good Air Twin 150 hp fans
Short Circuited Bulk heads meant to control air flow fail forcing smoke through the main shaft Main fans no longer pull fresh air, they pump bad air to working areas
Signal never came & the two were found dead by fans Foreman Gene Johnson also perished from smoke With the fans still churning, smoke was forced further into mine
Foreman Harvey Dionne remembered an exploration shaft that had been drilled down from under the Jewell He removed the safety covering to allow fresh air to reach the 4800 level 12:15
Exploration Shaft This 48” shaft was big enough to deliver breathable to the far west section of 4800
Jewell shaft was where air entered mine & main travelway for miners
Greg Dionne took over “Caging” job passing out self-rescuers & helping men use them He died after helping dozens of men escape lower levels
1:02 All hoisting at #10 shaft ceased when double drum hoist man was overcome
Foremen Give Instructions to Evacuate Last Miner Hoisted Out Smoke Detected Surface Notified Supervisors Look For Fire Stench Warning Deployed Warning Reaches Miners 11:30 11:45 12:00 12:15 12:30 12.45 1:00 90 Minutes
It was difficult to determine who was still in the mine because the list of workers was kept inside mine at foreman’s office Those who escaped were not counted either Most showered & either went home or to a bar called “The Long Shot”
Two Models of were available W 65 BM-1447
Not required in hard rock or metal mines in 1972 There was a shortage of W65 rescuers available due to demand from coal mines W 65 BM-1447
Self Rescuer • Uses hopcilite to turn CO into breathable CO2 • Byproduct of reaction is heat - survivors had 2nd & 3rd degree burns on mouths • Air tests found Oxygen below 5% & CO above 3000 PPM • Oxygen levels below 16% are immediately dangerous to life • Autopsies determined most died within 40 to 60 seconds of exposure
Two miners, Tom Wilkinson & Ron Flory, were found alive & in good condition at the 4800 level They were saved by fresh air shaft that Harvey Dionne uncovered by Jewell shaft
Safe Zone The air supplied by the open shaft provided the two miners with a small “safe zone”
Probable cause of fire was spontaneous combustion of refuse near scrap timber used to backfill worked out stops Extensive ground falls & caving occurred in immediate area when timber supports were consumed, making investigation of area impossible
5 lessons learned at Sunshine Mine that should affect your emergency response plan
Lesson #1 “Only shaft fires could create evacuation problems in hard rock mines - the walls aren’t flammable & floor is wet.” Understand Murphy’s Law, “Whatever can go wrong, will go wrong” Plan for every contingency
Lesson #2 “When manager is away, everyone can pretty well figure out what to do in event of emergency” Everyone needs to have clearly defined roles Need to understand what to do & who has authority
Lesson #3 “The fire may not be that bad. Lets check it out & see if we can take care of it without disrupting production.” Assume worst & hope for best Decision to delay evacuation for 20 minutes cost miners their lives
Lesson #4 “We have detailed written emergency response plan that exceeds legal requirements. As long as signs in place, we don’t need to train or conduct drills ” Plan called for miners to be dropped off in a section they had never seen & walk out in poor visibility A team can have world’s greatest game plan on paper, but if not practiced, it will never work the way they planned