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Mark Roebert
KDC West – Ya Rona (4) Shaft Fire
Update - status of fire and fire fighting
strategy
25 July 2012
• Fire Fighting Strategy
• Fire Fighting - Sequence of Events
• Fire Fighting – MRS Feedback
• Ya Rona (4) Shaft – 31 Line Plans
• 36/31 Photos
Index
Ya Rona (4) Shaft Fire Update
2
• Risk Assessment
• Remove all persons from any area that could be contaminated (Seal damage and leakage,
fan failures)
• Close off and seal any workings on adjacent shafts that could be affected
• Establish a dedicated chimney
• Reconnoitre the area to see if you can locate the fire for direct fire fighting
• Install water sprays as to contain the fire
• Seal off appropriate areas to limit feed of O2 to the fire
• A seismic ring of 1km in radius has been established around the fire area
• No mining will take place within this ring
Fire Fighting Strategy
Ya Rona (4) Shaft Fire Update
3
• Fire Control Room established on surface
• Manned 24 hours per day by Senior Managers and Engineers, Environmental Engineering
Superintendents and Safety Officers and persons from Mines Rescue Services (MRS)
• A scribe is appointed to record the sequence of all events
• Abbreviated sequence of events
• A reverse chimney was established to downcast air down to 39 level through the stope and to
discharge up to 34 level. This then fed directly into stoped out areas to main fans on 24 level
• While chimney was being established, reconnaissance was done on 38 level to gain access in stope.
Access could not be gained due to high temperatures and convergence
• Point of attack moved to 36 level
• Limited access into stope, but fire located and direct fire fighting attempted
• Unable to extinguish
• A number of seals installed on various levels to limit air flow into fire area
• Preparations and reconnaissance done on 34 level to install a water barrier
• Double bank water sprays installed in 34/31 1W and 1E gully
• Reconnaissance done on 30 level to establish a second line of defence (bad ground conditions
encountered and no access into reef horizon)
Fire Fighting – Sequence of Events
Ya Rona (4) Shaft Fire Update
4
• Abbreviated sequence of events (continued)
• Water sprays are monitored continuously
• Rock falls are taking place in 1W and 1E gully
• Further lines of sprays are being installed in gully below 1W and 1E to ensure that fire will be
contained
• The chimney and other critical areas are monitored 24 hours per day with hourly reports on
airflow, temperatures, visibility and gas readings
• The essential services manning the pump chambers on 38, 42 and 43 levels under the
personal supervision of MRS team
Fire Fighting – Sequence of Events
Ya Rona (4) Shaft Fire Update
5
• To date (20 July 2012 at 08:00) 170 MRS teams have been used
• Teams from as far away as Welkom and Thabazimbi have been called in to assist
• All MRS teams are fully briefed and de-briefed by fire control
• A full risk assessment is done by each team before any work commences
• One injury has been reported by a MRS team member
• Contused arm with slight abrasions (caught between man carriage and ventilation door)
• Some of the work completed to date
• 2,000m of 200mm pipe and 2,000m of 150mm pipe installed
• 3,000m of electrical cable installed
• Mobile compressor installed as back-up
• Booster pump station installed for water pressure
• 30 Tunnel seals installed
• 6 Fans and sets of ventilation doors installed
• 1,000m of spray pipes installed
• 2,500m of fire hoses installed
Mines Rescue Services
Ya Rona (4) Shaft Fire Update
6
• The majority of this work has been completed in an environment with low visibility (0-
5,0m), with high toxicity (CO – up to 20,000ppm; CO2 – up to 60,000ppm), and
temperatures of up to 47oC
• All the MRS teams are fully trained and equipped to deal with the conditions referred
to above
• The fire control room continuously making decisions on further tactics to contain and
extinguish the fire based on reports by the MRS teams
Mines Rescue Services
Ya Rona (4) Shaft Fire Update
7
Ya Rona – 31 Line Area Plan
8
Old worked out area
between 38 Level and
28 Level – no mining
operations
(Average depth below
surface 2,800m; last
mining activities in
2000)
38 Level
34 Level
Ya Rona – 31 Line on 36 Level
9
Ya Rona – 31 Line on 34 Level
10
Water Sprays
Ya Rona – section view through 31 Line
11
38 Level
39 Level
37 Level
35 Level
36 Level
34 Level
32 Level
30 Level
28 Level
Bank of water sprays
RBH chimney
38L to 34 L
Ya Rona – Fire in 36/31 Stope
12