Dust Control In Hard Rock Mines

1. Dust Control In Hard Rock Mines What You Can’t See Can Kill You.

2. Dust Control In This Mine Is A Large Complex Problem Many items discussed in this presentation requires problem solving at all levels of an operation. It may require engineering, operations, or maintenance groups to assist to ultimately solve. It requires a total team effort from all underground personnel & other site-wide groups.

3. Dust Control In Any Mine Is A Large Complex Problem Dust can cause health related issues whether it is a short acute related health problem or a long term systemic problem like silicosis. Prevention of dust is everyone’s problem. We all breath the same air, if we don’t take care of it. In other words: “It can kill you.”

4. Why Can Dust Get So Bad Here? • Fact: Major dust compliance problems in hard rock mines is caused by silica (quartz) in the rock. Mines high in silica content rock, 8% or more, are far more likely to have dust problems than those where there is less silica. • Fact: On average the rock in this mine is 40% silica content. Depending where you mine it can go higher. • Fact: Exposure to silica dust can cause silicosis.

5. Major Source of Dust Generation • Blasting • Mucking & Haulage • Drilling & Bolting • Ore passes • Crushers • Conveyors Systems • Backfill Process • Road Headers • Shotcreting • Fresh Intake Mine Dust

6. Control Measures for Correction & Reduction in Dust • Water sprays & Spray Bars • Ventilation • Control of drill dust • Control of conveyor dust • Control of ore pass dust • Control of mucking & haulage dust • Control of blasting dust • Control of road-header dust • Control of fresh air intake dust

7. Control Measures

8. Good Dust Control Requires Good Regular & Consistent Maintenance Factors that can lead to high dust levels on drills: Lack of Proper Maintenance Failure to use water Inadequate quantities of water Plugged water holes in drill steels Dull drill bits Dry collaring. Poor Maintenance on dust collector systems Drill Dust Control

9. Crushers & Rock Breakers • Water Sprays Systems • Dust Collector Systems • Ventilation Systems All require regular maintenance & attention. Disabling dust control systems are a bad practice that can cause long term health threats.

10. Conveyor Belt Dust Control

11. Possible Solutions to Conveyor System Dust

12. Solutions to Conveyor Transfer Box Dust May Require Installing & Properly Maintaining Dust Collector Systems Moving Rock Moves Air.

13. Maintenance of Water Spray & Sprinkler Systems

14. Solving Ore Pass Dust • A critical step in dust control is to prevent it’s escape & dispersal. • Confinement can be accomplished by systems of stoppings & air tight doors, curtains, spray bars, or isolations of passes away from travelways. • Dust can be reduce by wetting before delivery & adding water at the tipping site by spraying rock as it falls into passes.

15. Mucking & Haulage Dust Control Large Strides can be made to improve dust during this cycle. • Improvement to water trucks sprinklers. • Installation of mine wide sprinkler systems. • Dust surfactants testing & implementations. • Wetting down entire muck area prior to removal of material.

16. Blasting Dust Control • Thoroughly wetting down area surrounding the blast (Back, Ribs & Seal) before a blast will help settle dust from previous operations from becoming airborne.

17. Blasting Dust Control • Uniform rock moisture content of only 1% greatly reduces dust compared to dry rock both before & after a blast.

18. Shotcreting Dust Control Note: Predampening & washing down of rock surfaces in shotcreting zone will greatly improve adhesion of product & eliminates a lot of dust that can be liberated during pneumatic application of product. • When dry systems are utilized predampening of product can reduce dust. • Also spray bars in close proximity can knock down goodly amounts of generated dust.

19. Road Header Dust Control Dust Control for machines like roadheaders usually depend on some degree of dust cloud confinement.

20. Road Header Dust Control Managed Through Ventilation & Water Sprays

21. Fresh Air Intake Dust • Dust is liberated from other sources (i.e. process facilities, haul roads, backfill stockpiles. • Possible solutions: • Surface application of dust surfactants around fresh air intakes. • Increased water trucks scheduling. • Better dust control at surface crusher facilities.

22. Respiratory Protection Ultimately it is the objective of the safety department to do away with mandatory respiratory protection for all underground personnel. This will only be possible by diligent efforts of all personnel underground. There are definitely in roads that need to be made. Some of it is behavioral. Some of it is improvement in conditions that create dust releases. It will require everyone’s help & active participations to solve.

23. Let’s Talk About Near Misses & Accidents • We all know that accidents & near misses are when conditions & behaviors run close enough together to cause an incident the only way to control them is to separate conditions away from behaviors. The farther apart these are the greater margin of safety. You say, “What does that have to do with dust control?

24. Conditions Can Drive Behaviors& Behaviors Can Drive Conditions What conditions can drive behaviors? How do we correct them? What behaviors can drive conditions? How do we correct them? The Key to solving this problem is what?

25. You You may not be able to control how your fellow worker will react. The Key is being able to control how you react. Proactive Safety can help solves problems. Collectively if we all choose to do the most productive correct solution to this problem, It won’t belong to until we all have eaten this elephant. It starts with the first bite.

26. In Summary • Dust is by product of the mining process. • It take daily commitment from all personnel underground to solve this problem every shift. • Remember controlling dust every day can keep the respirator & 02 bottle away. • Please do your part every day.

27. Created by Pat GazewoodA.k.a. Capt. Shotcrete Thanks to Niosh for source information used in this presentations.