Minerals North Conference Update on Equity Silver Mine

Transcription

1 Minerals North Conference Update on Equity Silver Mine Mike Aziz, Site Manager, Equity Silver April 26, 2018

2 Agenda Where is Goldcorp Overview of Equity Operations & Closure Top Closure Issues at Equity Long Term Financial Assurance Tailings dam remote monitoring 2

3 About Goldcorp A senior gold producer focused on responsible mining practices with safe, lowcost production from a high-quality portfolio of mines Employs over 14,000 people throughout the Americas Six mines, four development projects and three joint ventures Values: Safe, Productive, Responsible Vision: Together, Creating Sustainable Value In 2017, produced 2.6 million ounces of gold LATAM Peñasquito, MEXICO Cerro Negro, ARGENTINA Alumbrera, ARGENTINA 37.5% Pueblo Viejo, DOM. REPUBLIC 40% NuevaUnión, CHILE 50% Norte Abierto, CHILE 50% Operations Projects CANADA Porcupine, ONTARIO Musselwhite, ONTARIO Red Lake, ONTARIO Éléonore, QUEBEC Coffee, YUKON Borden, ONTARIO Century, ONTARIO Cochenour, ONTARIO 3

4 Goldcorp s Closed Sites Where is Equity Silver? 4

5 5 360 Virtual Tour by VRify (

6 6 360 Virtual Tour by VRify (

7 7 Aerial View - Equity Silver Mine

8 Equity Silver Production Stats Production from 1980 to 1993 Silver 72.3 million oz Gold 498,000 oz Copper million lbs 21,500 tonnes/day mined 9,000 tonnes/day milled Averaged 158 employees 8

9 9 Main Zone Pit

10 10 North Zone Underground

11 11 Milling

12 12 Milling

13 13 Milling

14 14 Shipping Concentrate

15 15 Refining

16 16 Plantsite Prior to Closure

17 17 Plantsite After Closure

18 18 Ritchie Bros Auction 1994

19 Waste Rock Dump Cover Original waste dump cover was 1 metre of uncompacted till 40% infiltration Final cover started in 1990 to reduce water infiltration 0.5 m compacted till 0.3 m uncompacted till Expected 2 to 5% water infiltration and decreased oxygen infiltration 19

20 20 Waste Rock Dump Cover

21 21 Waste Rock Dump Cover

22 22 Waste Rock Dump Cover

23 ARD Generation Equity first learned that the waste rock and ore would oxidize and produce ARD in 1982, after a year and a half of construction and two years of production 23

24 Waste Rock Dumps 3 waste rock dumps covering 130 Ha 80 million tonnes of PAG rock ARD collection system to contain drainage 24

25 25 ARD Collection

26 26 ARD Collection

27 ARD Stats Annual ARD volumes averaged 899,000 m 3 from 1985 to 2014 Average Lime consumption for 1985 to 2014 is 4611T ph Acidity Cu Fe Zn Avg Min Max All values in mg/l except ph 27

28 Treated ARD Annual ARD treatment volumes averaged 983,000 m 3 from 2004 to Avg ph Acidity Cu (t) Fe (t) Zn (t) ARD Plant Feed Treated Water All values in mg/l except ph 28

29 ARD Cycle at Equity ARD Collection ARD Storage ARD Treatment Treated Water Discharge 29

30 Equity Permit Limits Parameter Limit Dissolved As 0.05 mg/l Dissolved Al 0.50 mg/l Dissolved Cd 0.01 mg/l Dissolved Cu 0.05 mg/l Dissolved Fe 0.30 mg/l Dissolved Sb 0.25 mg/l Dissolved Zn 0.20 mg/l Total Ammonia NH mg/l Nitrate (NO 3 ) 10.0 mg/l Nitrate (NO 2 ) 0.30 mg/l Total Suspended Solids 50.0 mg/l ph Discharge to Buck and Foxy Creeks based on dilution with creek flows and dissolved copper levels in the discharge water 30

31 Security Bond Review Long term security bond held as letter of credit - currently $ M Main components of the security calculation are fixed costs, variable costs, lime costs, periodic costs. Triggers used between five year bond review intervals to minimize risk of under-funding (lime unit cost, lime use, power) Uncertainty lies mainly in lime consumption, but also in unit costs and interest rates MEMPR, MoE, NRCan, Local Landowner, Goldcorp attend meetings (First Nations, DoH, EC invited) 31

32 32 Tailings Dams Remote Monitoring Instrumentation includes: 10 GNSS (GPS) receivers 6 prisms 18 piezometers 5 cameras 1 weather station 2 pond water level stations 32

33 Tailings Dams Remote Monitoring Stations 33 Solar Panel Radio Antenna GPS Data Logger Battery Box Vib Wire Piezo & Inclinometer 33

34 34 Tailings Dams Remote Monitoring GPS Stations

35 35 Tailings Dams Remote Monitoring Prisms

36 36 Tailings Dams Remote Monitoring Vibrating Wire Piezometers

37 37 Tailings Dams Remote Monitoring Camera Views

38 38 Tailings Dams Remote Monitoring Weather Station

39 39 Tailings Dams Remote Monitoring Water Level Indicators

40 40 Tailings Dams Remote Monitoring Alarms

41 Tailings Dams Remote Monitoring Alarms Monitoring Instrumentation Alarm Pond Water Level Transducer (2 stations) looking into call Pore Water Pressure Dams Vibrating Wire Piezometer Movement Dams Total station & prisms Monitor trends Movement Dams GPS Weather Extremes Weather station Setting threshold for rainfall 41

42 Summary Equity mine has been closed since 1994 and will be collecting and treating ARD for the long term to prevent environmental impacts The financial assurance for the site is currently $ million, with annual operating costs between $1.7 to 2.8 million Tailings dam remote monitoring has become a focus to better monitor the performance of the dams and provide early detection of any potential issues 42

43 43 Any Questions?

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