Original EA Amendment

3.2. Alternatives to the Amendments ............................................................................................... 62

3.2.1. Amendment #1 .......................................................................................................................... 62

3.2.2. Amendment #2 .......................................................................................................................... 63

3.2.3. Amendment #3 .......................................................................................................................... 63

3.3. Standard Criteria Assessment .................................................................................................. 63

4. Upper Mundic Gully TSF Description........................................................................................ 66

4.1. Upper Mundic Gully Location and Catchment Description ....................................................... 66

4.2. Topography and Drainage ........................................................................................................ 71

4.3. Proposed TSF ........................................................................................................................... 76

4.3.1. Basis of Design ......................................................................................................................... 81

4.3.2. Dam Break and Consequence Category Assessment ............................................................. 82

4.3.2.1. Failure mechanisms ................................................................................................................. 83

4.3.2.2. Consequence Category Assessment ....................................................................................... 83

4.3.2.2.1.

ANCOLD Guidelines ......................................................................................................... 83

4.3.2.2.2.

DETSI Guidelines .............................................................................................................. 84

4.3.2.2.3.

Dam Break Consequence Results .................................................................................... 84

4.3.2.2.4.

Consequence Classification ANCOLD.............................................................................. 85

4.3.2.2.5.

Consequence Classification DETSI .................................................................................. 85

4.3.2.2.6.

Environmental Spill/Failure to contain (Overtopping Consequence) ................................ 86

4.3.2.2.7.

Environmental Spill/Failure to contain (Overtopping Consequence) - ANCOLD..............87

4.3.2.2.8.

Environmental Spill/Failure to contain (Overtopping Consequence) – DETSI .................87

4.3.2.2.9.

Failure to contain (Seepage) – Consequence .................................................................. 88

4.3.3. Tailings and Water Management .............................................................................................. 89

4.3.4. Water Balance ........................................................................................................................... 89

4.3.5. Deposition Volumes .................................................................................................................. 94

4.3.6. Decant Pond.............................................................................................................................. 96

4.3.7. Seepage and Tunnel Management........................................................................................... 96

4.3.8. Flood Potential .......................................................................................................................... 97

4.3.9. Clean Water Diversion ............................................................................................................ 100

4.3.10. Potential impacts of future deposition expansion.................................................................... 100

4.3.11. Process Plant Flow Sheet ....................................................................................................... 101

v

Wulguru Technical Services Pty Ltd – Supporting Information Report

Powered by