Mammoth Water Extractor Risk Matrix
Mammoth Water Extractor
FREQUENCY-LIKELIHOOD
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SEVERITY-CONSEQUENCE
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Stemming Wet Holes
- Ensure that the stemming material is suited to the stemming length to achieve the required result
- Water in the stemming area will affect the effectiveness of a consolidated stemming
- Bottom charge all water-filled holes. This will result in water on top of the charge
- Remove the water and explosives gunk in the stemming length with a water extractor before stemming the hole. The hole will be dry and the stemming can affectively be consolidated.
- 10% aggregate is normally used when;
- holes are situated in a pool of water
- to ensure the optimum fragmentation in very hard rock
- a short stemming is needed i.e., hard rock in collar area that may create slabbing.
- no flyrock is allowed in restricted areas
Drill chippings (not fine sand) can be used effectively in dry holes as indicated below
General Stemming Chart ‐ Flyrock effect
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