REV97590

• Permit No: M1980244
• IBM Index Class Name: Revision
• Doc Name: VOLUME V TABLE OF CONTENTS
• Type & Sequence: AM8
• Media Type: D
• Archive: No

III IIIIIIIIIIIIIIII
March 2000 -i- 993-2099.150
voLUME v
TABLE OF CONTENTS
EXECUTIVE SUMMARY .............................................................................1
1.0 INTRODUCTION ..................................................................................1
1.1 Project Description ............................................................................ 3
1.2 Scope of Work .................................................................................5
1.3 Design Criteria ................................................................................. 7
2.0 SITE DESCRIPTION .......................................................................... .. 15
2.1 Location and Topography ................................................................ .. 15
2.2 Climate ...................................................................................... .. 15
2.3 Geology ...................................................................................... .. 17
2.4 Underground Workings .................................................................... . 18
2.4.1 Remediation of Underground Workings Within Limits of Phase II and
Phase III Areas ...................................................................... . 18
2.4.2 Remediation of Underground Workings Within Limits of Phase IV ...... . 19
2.5 Seismicity .................................................................................... . 22
3.0 SITE SUBSURFACE CONDITIONS ......................................................... 23
3.1 Previous Site Investigations ................................................................ 23
3.2 Golder Site Investigation ................................................................... 23
3.3 Site Geotechnical Conditions .............................................................. 24
4.0 VALLEY LEACH FACILITY DESIGN ............................ ......................... 26
4.1 General ............................................................... .........................26
4.2 Site Layout ........................................................... ......................... 27
4.3 Staged Construction ................................................ ......................... 28
4.4 Valley Leach Facility Foundation ................................ ......................... 28
4.5 Underdrains .......................................................... .........................30
4.6 Liner System ......................................................... ......................... 31
4.6.1 Ore Storage Area ........................................... ......................... 31
4.6.2 Phase IV PSSA .............................................. ......................... 32
4.6.3 Extetal Ponds .............................................. ......................... 34
4.6.3.1 Phase I/II/III External Pond ....................... ......................... 34
4.6.3.2 Phase IV External Pond ........................... ......................... 34
4.7 Leak Detection System ............................................ ......................... 35
4.7.1 Phase IV VLF ............................................... ......................... 35
4.7.2 Phase IV External Pond ................................... ......................... 35
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