This information has been put together in response to the Investor Mining and Tailings Safety Initiative.
Our approach
Tailings storage facilities (“TSFs”) are a key part of our mining and processing operations and our goal is to ensure zero harm from them, as outlined in our Group Tailings Policy. Tailings management is part of our corporate risk management system and we have a structured and robust approach to the risk classification of our existing and planned TSFs. We evaluate the consequence to human and environmental health in line with the classification systems of the Australian National Committee on Large Dams (“ANCOLD”) and the Canadian Dam Association (“CDA”). We conduct regular internal and external audits to monitor, measure and evaluate the effectiveness and safety of our TSFs. The results of these audits are reported back to site, Senior Management and the Board on a regular basis.
| 1. "Tailings Dam" Name/identifier |
Houndé Mine | Ity Mine | Mana Mine | Sabadola-Massawa Mine | Lafigué | Kalana Mine | |
| 2. Location | 11°25'3.28''N, 3°32'31.40''W |
TSF 1- 6°52'36"N, 8°07'33"W |
TSF 2-8°07'33"W |
11°57'20'' N, 3°24'46'' W |
TSF 1 13o 12’ 42 N 12o11’ 53 W TSF 1B - 13o 12’ 54 N 12o7’ 61 W |
8°16'23.22"N 4°39'28.39"W |
10°48'04.89"N 8°11.5'50.91"W |
|
3. Ownership |
Owned and operated |
Owned and operated |
Owned and operated |
Owned and operated. |
Owned and operated. |
Owned and operated |
Owned |
| 4. Status | Active |
Inactive |
Active |
Active |
Active |
Active |
Inactive |
| 5. Date of initial operation |
1 November 2017 |
8 April 2019 |
June 2024 |
2008 |
March 2009 TSF 1B – June 2024 |
July 2024 |
Commence operation in 2004 and halted operation in 2017 |
| 6. Is the Dam currently operated or closed as per currently approved design? |
Currently operated in accordance with Knight Piesold (“KP”) operating manual – PE23-000624_33 TSF, WSD and WHD Operation, maintenance, and Surveillance Manual. |
Currently operated in accordance with Knight Piesold (“KP”) operating manual – PE23-00743_19 TSF Operating Manual. |
Currently operated in accordance with Knight Piesold (“KP”) operating manual – PE24-00900_19 TSF Operating Manual. |
Currently operated in accordance with Knight Piesold (“KP”) operating manual – PE23-00773 TSF Operating Manual. |
Currently Operated in accordance with Operations Manuals. Basis of Design ANCOLD (2019) |
Currently Operated in accordance with Operations Manuals. Basis of Design ANCOLD (2019) |
Currently under care and maintenance. Currently not closed |
| 7. Raising method | Downstream |
Downstream |
Downstream |
Stage 1 – 3 Upstream and Stage 4 Downstream. Stage 5 Modified Center Line |
TSF 1 - Upstream TSF 1B – Downstream |
Downstream |
Upstream |
| 8. Current maximum height |
Wall height varies against natural topography. Average current wall height 32.0 m. Maximum wall height is 44.2m for Cell 1 and 36.2m for Cell 2. |
Average current wall height 30.1m. Maximum height is 38.0 m at South wall. |
TSF2: Maximum wall height is 15.3 m at East/ South Average wall current height is 10.0 m |
Wall height varies against natural topography.
Maximum current wall height 24.3m for East Cell and 24.3m for West Cell |
TSF 1 – Maximum Height 26 m TSF 1B – Average height 3 m Maximum height 1 |
Maximum Height 14 m |
Maximum Height 11 m |
| 9. Current Tailings storage impoundment volume |
33 Mt or 27.5 Mm3 (Slurry settled density 1.2 t/m3). |
21 Mt or 19 Mm3 @ 1.1 t/m3 |
17.8 Mt or 13.7 Mm3 |
40.27Mt Mt or 28.76 Mm3 (Slurry settled density 1.4 t/m3). |
TSF 1 – 53 Mt or 30.9 Mm3 (Slurry settled density 1.55 t/m3). TSF 1B – 0.87 Mt
|
1.7 Mt or 1.9 Mm3 (Slurry settled density 1.1 t/m3 ) |
0.64 Mt at 1.55 t/m3 |
| 10. Planned tailings storage impoundment volume in five years’ time |
50.6 Mt or 42.16 Mm3 (Slurry settled density 1.2t/m3). |
TSF 1 = 11.2 Mt or 8.6Mm3 (Slurry settled density 1.3 t/m3). |
TSF 2 = 26.4 Mt (Slurry settled density 1.3 t/m3 |
50.8 Mt or 36.2 Mm3 (Slurry settled density 1.4 t/m3). |
60 Mt or 38.7 Mm3 (Slurry settled density 1.55 t/m3). |
41 Mt or 29 Mm3 (Slurry settled density 1.41 t/m3) |
N/A |
| 11. Most recent independent expert review |
Annual EoR Review, Knight Piesold, July 2024 |
Annual EoR Review, Knight Piesold, November 2024
|
Annual EoR Review, Knight Piesold, August 2024
2024 Independent ICMC audit completed. |
Annual EoR Review, Knight Piesold, August 2024
Dam Safety Review conducted by Knight Piesold (2020), Perth.
2024 Independent ICMC audit completed.
|
Annual EoR Review, Knight Piesold, August 2024.
Dam Safety Review conducted by Knight Piesold (2025), Perth.
2024 Independent ICMC audit completed.
|
Annual EoR Review, Knight Piesold, December 2024.
. |
Independent Audit planned for April 2024 |
| 12. Do you have full and complete relevant engineering records including design, construction, operation, maintenance and/or closure. |
Yes for Stages 1-9. |
Yes, for Stage 1 commissioned in March 2019 and for Stage 2 which was handed over in July 2020. |
Yes
Operating Manual refer to PE23-00773 TSF Design for Construction 401-081_A3005 |
Yes Construction Reports Stage 5 completed
Operating Manual refer to PE24-01364_ TSF Operation, Maintenance, and Surveillance Manual
|
Yes
PROJECT 301012-01512 - OM-0002: Tailings Storage Facility 1 - Operations Manual |
Yes, Construction Reports for Stage 1 completed
Operating Manual refer to PE24-00829_TSF Operation, Maintenance, and Surveillance Manual |
Yes, Closure plan refer to R_Kalana Mine Closure Plan 9112006 |
| 13. What is your hazard categorisation of this facility, based on consequence of failure? |
High A (ANCOLD 2019)
|
High A (ANCOLD 2019) |
Extreme (ANCOLD 2019) |
Extreme (ANCOLD 2019) |
High A (ANCOLD 2019) |
High B (ANCOLD 2019) |
Low (ANCOLD 2019 and SANS 10286) |
| 14. What guideline do you follow for the classification system? |
Australian National Committee on Large Dams (ANCOLD 2019) Guidelines. |
Australian National Committee on Large Dams (ANCOLD 2019) Guidelines. |
Australian National Committee on Large Dams (ANCOLD 2019) Guidelines. |
Australian National Committee on Large Dams (ANCOLD 2019) Guidelines |
Australian National Committee on Large Dams (ANCOLD 2019) Guidelines |
Australian National Committee on Large Dams (ANCOLD 2019) Guidelines |
Australian National Committee on Large Dams (ANCOLD 2019) Guidelines |
| 15. Has this facility, at any point in its history, failed to be confirmed or certified as stable, or experienced notable stability concerns, as identified by an independent engineer (even if later certified as stable by the same or a different firm). |
No |
No |
No |
No |
No |
No |
No |
| 16. Do you have internal/in-house engineering specialist oversight of this facility? Or do you have external engineering support for this purpose? |
External - Knight Piesold (Perth) - who have been involved with each dam embankment raise since inception. |
External - Knight Piesold (Perth)- who have been involved with each dam since inception. |
External - Knight Piesold, Perth |
External- Knight Piesold, Perth |
External - Knight Piesold, Perth |
External - Knight Piesold, Perth |
External - Knight Piesold (Denver) |
| 17. Has a formal analysis of the downstream impact on communities, ecosystems and critical infrastructure in the event of catastrophic failure been undertaken and to reflect final conditions? If so, when did this assessment take place? |
Yes. Undertaken April 2019. |
Yes. Undertaken during 2017/2018 design period. Latest update in 2023 |
Yes. Latest update in 2023
|
Yes. Undertaken in 2012. Latest update completed in 2017 |
Yes undertaken in 2021 |
Yes. Undertaken in 2021. |
Yes. Undertaken in 2006 contained in the Design Report by METAGO |
| 18. Is there a) a closure plan in place for this dam, and b) does it include long-term monitoring? |
Closure plan concept of the Houndé mine performed by Socrege in April 2023 and Rehab Cost in Asset Reclamation Obligation (ARO) 2023 Crop trials of vegetation with tailing material on going |
Closure plan concept developed by Westago, Asset Reclamation Obligation 2023. Concept Mine Closure Plan ongoing. |
Closure plan concept Bureau Performance and Digby Wells developed, Asset Retirement Obligation (ARO) 2023 Mine Closure Plan update ongoing |
Yes. Closure plan concept Synergie and ERM developed and ARO 2023. |
Yes, Closure plan exist |
Closure chapter plan available |
Yes, Closure plan refer to R_Kalana Mine Closure Plan 9112006 |
| 19. Have you or do you plan to assess your tailings facilities against the impact of more regular extreme weather events as a result of climate change, e.g. over the next two years? |
Yes. TSF is monitored in the case of extreme weather conditions. Example 1 in 100 AEP (Annual Exceedance Probability) wet season or 72 hr flood. |
Yes. Due to location within considerable high rainfall area (average >1.5m pa), TSF is monitored with respect to catchment and wet season runoff from surrounding landscape. |
Yes. Freeboard volume more than sufficient to contain PMP. |
Yes. Freeboard volume more than sufficient to contain PMP. |
Yes. Freeboard volume more than sufficient to contain PMP |
Yes. Freeboard volume more than sufficient to contain PMP |
Yes, climate change study in progress, outcomes of which will inform AEP assessment by the Engineer of Record. |
|
20. Any other relevant information and supporting documentation. Please state if you have omitted any other exposure to tailings facilities through any joint ventures you may have. |
Dam has a clay lining and a HDPE liner. |
Dam has a clay lining and a HDPE liner. |
Dam has a clay lining and a HDPE liner. |
3rd Party Independent Review completed in 2023. |
Upstream Dam. There are monitoring bores and piezometers at the downstream of the embankment. |
Dam has a clay lining and a HDPE liner. |
|
Sustainability Report 2024
Read about our ESG strategy and the significant sustainability milestones reached in 2024.
