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Appendix E Greens Creek Liner Dry Stack Construction

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Page 1: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Appendix E

Greens Creek Liner Dry Stack Construction

Page 2: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—
Page 3: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Appendix C Photographs— Proposed Stage 3 Tailings Expansion

Greens Creek Mine

Admiralty Island, Alaska

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Page 4: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

920 Level Existing Mill Facility

Existing dry-stack tailings facility (looking north) Expansion area in foreground

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Page 5: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Looking east-northeast in Hawk Inlet (July 2010) Marine terminal on left; existing tailings facility on right

Hawk Inlet Marine Terminal (areal view looking east)

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Page 6: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Tailings Foundation Preparation

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Page 7: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Vegetation clearing in preparation for expansion of tailings facility

Removal of peat and reclamation materials ahead of foundation preparation for tailings placement

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Page 8: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Foundation preparation (Where necessary—excavating and grading to achieve desired slopes)

Foundation preparation (Where necessary—placement and compac-tion of 6-inch minus rock fill)

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Page 9: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Final foundation for tailings facility (maximum slope 2H:1V; minimum slope 2%)

Installation of sub-drains beneath tailings liner. Purpose of these sub-drains are to reduce groundwater pressure on liner.

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Page 10: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Perforated sub-drain pipe bedded in gravel, wrapped in filter fabric geotextile and covered with the bedding sand layer

Sub-drain pipeline wrapped in filter fabric geotextile

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Page 11: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Bedding and sand layer—placement and grading (1-foot thick layer increased to 2-foot layer on slopes greater than 15%)

Bedding sand layer—grading and compaction

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Page 12: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Placement of 80-mil HDPE liner

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Page 13: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Welding of 80-mil HDPE liner

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Page 14: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Anchor trench for 80-mil HDPE liner (before backfilling of trench)

Anchor trench for 80-mil HDPE liner (compacting trench backfill)

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Page 15: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Installation of geocomposite fabric drain layer over 80-mil HDPE liner

Installation of above-liner Drains (on top of the 80-mil HDPE liner). Purpose of these above-liner drains are to collect and transport any

water seeping through tailings to wet well locations for eventual treatment in water treatment facility.

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Page 16: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Water from sub-drains and above-liner drains routed to “wet wells” installed in the tailings facility. From wet wells, water will be routed to water treatment plant. Ultimately, water is discharged in Hawk

Inlet under NPDES permit standards.

Close-up view of the base of the wet well with connecting drain pipes.

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Page 17: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Placement and compaction of sand service layer (on the top of the geo-composite fabric layer and synthetic liner)

Initial tailings placement on sand service layer

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Page 18: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Instrumentation and monitoring (piezometers, lysimeters, water sample points, etc.)

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Page 19: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Tailings Operation

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Page 20: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Filter presses within mill (“squeeze” water to obtain an approximate 10-12% moisture content)

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Page 21: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Covered tailings storage at mill

Loading tailings into Max Haul truck at mill (Notice the open lid—this closes for transport of tailings to disposal facility)

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Page 22: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Max Haul truck on B road in route to tailings disposal facility

At tailings facility. View of “dirty road” (gray-colored road on left) versus “clean road” (brown-colored road on right)

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Page 23: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Max Haul truck dumping tailings (Notice compacted area in fore-ground)

Spreading of tailings in approximate 1-foot lifts by dozer (Notice compacted tailings in foreground)

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Page 24: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Tailings compaction with vibratory compactor

Truck wheel-wash facility (All vehicles exiting tailings site must pass through this facility).

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Page 25: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

Truck wheel-wash facility. Goal is wash truck wheels to prevent tracking of tailings material onto “clean” roads outside the tailings

facility

Interim reclamation on tailings facility (hydro-mulching/hydro-seeding)

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Page 26: Appendix E Greens Creek Liner Dry Stack Constructiona123.g.akamai.net/7/123/11558/abc123/forestservic.download.akam… · Greens Creek Liner Dry Stack Construction . Appendix C Photographs—

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