Petra Diamonds Limited announced Update regarding Tailings Storage Facility (TSF) wall breach at Williamson in Tanzania. In follow up to its announcement of 30 November 2022, Petra provides a further update regarding the TSF wall breach at the Williamson mine on 7 November 2022. Precautionary measures, detailed in the announcement of 30 November 2022, to contain the tailings material and strengthen the New Alamasi water dam were completed in early January 2023.

The creation of a safety bund, mitigating risk in affected areas, has also been completed. Environmental assessments, with the assistance of independent experts, continue to be carried out by Williamson Diamonds Limited (WDL) to determine how best to clean-up or remediate affected areas. Trials are also in place to identify the best land use options post remediation of affected areas.

To date, these studies indicate that areas lying within the Mining Lease Area (MLA) are best suited to be returned to wilderness, either as forest or wetlands, through amelioration of the soil and revegetation. Areas outside of the MLA are treated according to the depth of tailings material, where thinner layers of tailings can be mixed into the surrounding soil and thicker layers can be used for agricultural purposes following trials which demonstrate that enrichment with compost will enable cash crops to be farmed on a viable basis. Since initial estimates announced on 10 November 2022, it has been confirmed that a total of 286 individuals from 50 houses were relocated as a result of the breach.

Of these, 130 individuals from 22 houses returned back to their former homes which have been deemed safe. 145 individuals from 23 houses are currently accommodated in houses rented by WDL and 11 individuals from five rental houses have secured alternative rental accommodation. All affected households have been provided with accommodation and humanitarian relief within the village they were displaced from.

In addition, the vulnerability of affected people is an important consideration and a key component of WDL's work. Psychosocial support is being provided and once any issues are identified, a mitigation process is implemented. The evaluation of impacted livelihoods, undertaken by WDL and independent experts, to ensure that affected individuals are appropriately compensated is nearing completion.

Once finalised, a report will be submitted to government authorities for approval. Once approval is received, WDL will commence with initial restoration measures (including monetary and in-kind compensation measures). Alternative agricultural land is being identified to enable farming activities for those affected to recommence as soon as possible and this work is ongoing in keeping with Tanzanian law and international standards for resettlement.

WDL, along with local, regional and national authorities, continues its extensive engagements with local communities to ensure that key stakeholders are kept informed of WDL's response, including planned remediation activities. Technical and Production: As announced on 30 November 2022, the root cause of the subsidence that led to the breach has not yet been determined and requires a forensic geotechnical investigation including detailed InSAR analysis to be completed. This work has been initiated and is being undertaken by an independent company that specializes in tailings dam design and management.

Estimates for completion of these studies remain between 6 and 12 months. Petra continues to work constructively with the Tanzanian Mining Commission and key findings will be published once complete. As announced on 30 November 2022, the root cause of the subsidence that led to the breach has not yet been determined and requires a forensic geotechnical investigation including detailed InSAR analysis to be completed.

This work has been initiated and is being undertaken by an independent company that specializes in tailings dam design and management. Estimates for completion of these studies remain between 6 and 12 months. Petra continues to work constructively with the Tanzanian Mining Commission and key findings will be published once complete.