13/2/08 Fundamental Analysis of Development Cycles at Xstrata NSW Mines ACARP Roadway Development Operator Workshops March 2008

2 Introduction Set out to benchmark the development rates across all XCN operations It was known that support density had an effect, and initially this was judged to be the major determinant on rates We were seeking to quantify the effect of support, and to find best practices across the group

3 Methodology Collection of data at each mine pillar geometry including boot position and lengths of overdrives support density and associated times process adopted - interaction of all equipment and functions equipment type and associated times crew sizes electronic reporting on ABMs used at two mines limited to two heading development Data analysis compilation of spreadsheet to simulate processes inclusion of means of standardisation of support and equipment for comparison of process steps

4 Spreadsheet Logic built in to simulate functions that had to wait for other functions to complete parallel performance of functions increasing length of wheeling time as pillar progressed change of shunt and wait positions where applicable support rules Complexity increased from Miner-bolter with one car (bolting and wheeling in parallel) to Bolter-miner with two cars (cutting, bolting and two cars independently wheeling in parallel) No allowance for delays – ideal process considered Set up in increments of 16m of roadway

5 Standard Cycles

6 Standard Cycles – Average Rates Process Rate (m/hr) Mine B (miner-bolter)7.5 Mine D (miner-bolter)6.9 Mine E (bolter-miner)5.0 Mine A (bolter-miner)4.7 Mine F (miner-bolter)4.4 Mine C (miner-bolter)3.8 Mine E (miner-bolter)3.6 Mine G (miner-bolter)2.8

7 Support Observations The amount of support required affects the process rate The amount of support varies widely from mine to mine Time taken to erect similar support is much the same from mine to mine Differences exist in the time taken to set up for bolting, or to change from bolting mode to cutting mode

8 Standard Roof Support Roof Support Density (bolts/m) Rib Support Density (bolts/m) Support Density (bolts/m) Mine D2.70 Mine B Mine F404 Mine C606 Mine A448 Mine E639 Mine G8412 XCN Comparable 426

9 Effect of Support Density on Rate Mine B Mine D Mine G Mine F Mine C Mine A* Mine E* Mine E

10 Comparable Support

11 Equipment Observations Three pieces of equipment in the cut and load sub-process: Miner – 4 types in XCN, each with different load out capacity, which varied ~100% Car – both car capacity and car speed varied ~100% Feeder – discharge time through the feeder (or boot) varied ~ 150% Combination of these has a major effect on process rate This combination is expressed as the rate at which the roof can be exposed for one round of support

12 Equipment Comparisons Cut Time (min) Wheel Time (min) Discharge Time (min) Total Time (min) Advance (m) Exposure Rate (m/hr) Mine D Mine B Mine E Mine E Mine F Mine C Mine G Mine A XCN Comparable

13 Effect of Equipment on Rate – Normal Support Mine B Mine D Mine A* Mine G Mine E Mine E* Mine F Mine C

14 Comparable Support, Comparable Equipment – Miner-bolter

15 Comparable Support, Comparable Equipment – Bolter-miner

16 Equipment Capacity Matched to Process MatchedNot Matched Mine AMiner, Car, Feeder Mine BMiner, Car, Feeder Mine CMiner, CarBelt Mine DMiner, Car, Belt Mine EMiner, Car, Feeder Mine FMiner, CarFeeder Mine GMiner, Car

17 Process Observations Once support variations and equipment variations are levelled, the remainder of the variation is process application

18 Bolter-miner vs Miner-bolter

19 Effect of Number of Cars

20 Effect of Mining Method

21 Cut then Bolt vs Batch Bolt

22 Potential Evolution Step 1 – Miner-bolter

23 Potential Evolution Step 2 – Bolter-Miner

24 Potential Evolution Step 3 – Bolter-Miner with 2 cars

25 Potential Evolution Step 4 – Bolter-Miner with 2 cars and SDRBs

26 Potential Evolution Step 5 – Bolter-Miner with SDRBs and Cts Haulage

27 Effect of Manning on Process Rate Manning has little relationship to process rate, but the process must be manned so that it works as designed

28 Conclusion Three measurable elements affect cycle time: Support density Equipment selection Process application You cannot affect the support density You can design your process You can select your equipment to achieve your process You must man your process to achieve it

29 Acknowledgements Thanks to development operators, engineers and superintendents for their help in providing data and comment for this presentation. Deming: “ Your system is perfectly designed to give you the results that you get”