Week 9

1. Week 9

2. CoAL

3. Things Missed Last Week • Show a map of your #6 coal and areas where you will have to cut roof rock because of your CM selection • Show a year by year timing map of the #6 coal producing 3 million or more clean tons per year • Have a schedule showing when and how much out of seam dilution will be going to the prep plant • Make sure your timing and equipment capacity accounts for the out of seam dilution you will take • Produce a year by year schedule of royalties or other fees you will be paying to land holders.

4. Provide the Same Schedule • Provide the same year by year mining schedule for your #3 met coal • The schedule should include estimated out of seam dilution and royalties paid to each land owner • When your met coal operation starts assume you will still keep 2 million tons of steam coal market using #7 coal • Lay out the same type of schedule for #7, but only through the time when you have mined out the met coal.

5. Complete Ventilation From Last Week • You did get close-ups of how you would vent panel areas, and air quantities • Check your air quantities against velocities to make sure you do not have excessive or deficient air speed • Approximately every 5 years or more often when there is a major shift in ventilation draw maps of the over-all vent system showing where air comes in – what routes it travels to get to the face- and how it returns to an exhaust

6. Complete Your Conveyor Work • Last week you size conveyor belts and motors and planned 5,000 feet per main belt run. • You did not have a map of the belt network • Provide a map of the belt network every 5 years or more often if there is a major change between 5 year intervals • For dewatering you proposed local sumps and piping to a main sump. • Provide maps of your sump and pipe network every 5 years or more often if there is a major change between 5 year intervals.

7. Add to Your Mine Map • Battery Barns • Underground Vehicle Service • Lunch area • Bathroom areas (I know you already show the returns)

8. Produce Year By Year Supply Acquisition Costs • Identify what components at what cost will be bought year by year for installation and extension of your belt network. • Identify the same for your dewatering system. • Develop your schedule and supplies for putting in stoppings and permanent mine seals

9. Start Your Ventilation Simulation • Pick a point where your ventilation system is short and air does not have to go too far • Then pick a point where your ventilation system is very extended • Finally pick an intermediate case in time • Set up these three cases for computer calculation (or if you prefer – long hand calculations) • Run at least one of the cases • Have a tentative mine fan pick

10. From Last Week • Draw out your flow sheet showing where materials and waste will go and what size it is. • Look for a kind of simplified spreadsheet layout that will help you understand the minimum I am after.

11. Last Task • By Friday of next week have your revised write-up done • You need not have written out all your appendices, but you should refer to them where you will have them • Keep my red notes in place and add your new changes and text in green

12. Diamond

13. Work on Your Underground • You have determined you will use a 3 level system in each of two areas of the underground pipe. • Draw in your shafts, haulage, travelways, ore passes and other facilities that will be in durable non-kimberlite ground. • These working should be in 3D minesight • They may include lunchrooms, workshops, parking areas, or areas for security scans.

14. Calculate • Calculate the volume of kimberlite that will have to be mined from your K1 and K2 areas each year • Show how you got the calculated amount (you are presumably not counting mega-diamonds since you did not attempt to define their frequency.

15. Draw the Cuts • Draw the area actually open in cuts into the kimberlite in years 1, 2, 3, 4, and 5 • Don’t draw in all the parallel entries – only what is actually open at each point in time

16. Ventilation Network • Draw in your ventilation network at the end of 5 years. • Simulate the airflows so that you have air quantities and heads • Your equipment is mostly diesel – make sure you are getting the required air to dilute the diesel emissions

17. Haulage • Plan out your underground haulage system • Show where each type of equipment will serve to move the ore • Draw out diagrams of your shafts and slopes that serve your underground mine.

18. Build a Manning Table • Build a month by month, shift by shift list of how many people doing what you will have on the job at the mine.

19. Copper-Gold

20. Develop Your Flow Sheets • Make sure your excel spreadsheet covers all 6 types of ore • Improve your spreadsheet to where I can input my ore grade and the spreadsheet will give me the mass balance all the way through the process • Account for any iron you process or recover • Account for your sulfuric acid production from your roasting

21. Develop the First Draft of the Appendix You Will Use in Your Report • MSOPIT requires specific recovery, cost, product values etc. • Show how you obtain each of these numbers and explain how you get those numbers from your process

22. Decide What Will Happen to Below Cut-Off Grade Ore • MineSight MSOPIT allows multiple processing for each ore type • The first process is the most intensive recovery process • The last process must be a complete waste – no recovery at all process • In-between you may have processes that get some recovery from lower grade ore (usually leach processes – though you don’t have to have them)

23. Possible Low Grade Processes • Leach processes are most common • You could crush and then take to leach pads but this requires both grinding and some significant rehandle costs • You could take ore to a dump area that gets leached • In practice some companies just leach their dumps for what ever they can get • In MineSight – even if you leach your dumps you have to have a class 2 dump that you don’t leach • There may actually be no rock that ever uses it, but you still have to have it in the program

24. Leaching Processes • A sulfide copper leach • Many involve dumped run of mine rock where acid and water are poured over it • Sulfide leaching may go on for 20 years or more and seldom does much more than about 10% recovery (unless the ore is crushed down and put on special pads) • Sulfide acid leaches will dissolve out copper and a little silver, but no gold. • The copper solutions are boosted in concentration using solvent extraction • The concentrated copper solution is sent to electrowinning and the copper is plated out • Recovered silver goes to the anode slimes that can be sent off to smelting

25. More Leach Options • Oxide Copper Leach • Some people will crush the rock and put it in smaller leach pad stacks • Sulfuric acid will directly dissolve copper out of copper oxides • It will also dissolve metallic silver, but not gold • Copper oxide leaching is far faster than sulfide leaching • You’d expect about 15 to 20% recovery in a few years without special pads or crushing • With special pads or crushing you might get 40 to 50% • Copper and silver in solution go through solvent extraction and electrowinning just like with the sulfide ore.

26. More Leach • Gold and Silver Leaches • Gold and Silver will leach from piles too but a cyanide leach is alkaline, which won’t leach copper • Lots of acid producing sulfides will also cause excessive cyanide consumption • Cyanide is very chemically active and does not last well in unfavorable environments • Silver will leach with Copper or with Gold – but Gold and Copper leaching are usually mutually exclusive • Pyrite encapsulated gold is not leachable

27. When You Have Your Numbers • Run the ultimate pit with MSOPIT • The output will tell you how much went to dump, leach, and mill • It will tell you what the average grade of your mill ore is • Use your models to predict the tailings volume you will have • Draw out the waste dumps and tailings pond you will have on 3D MineSight drawings with the open pit.