Governance, standards and guidelines

At Golden Mine Projects, our tailings management plans encompass the creation and continuous updating of various documents and procedures related to tailings management. These updates are carried out in alignment with our corporate policy and cover the following:

• Elaboration of a comprehensive construction management plan, which includes a construction quality plan and assurance protocols to ensure that construction aligns with the design specifications.
• Development and maintenance of a closure plan.
• Preparation of a Design Basis Report, water balance, water management plan, as well as a plan for tailings transportation and deposition.
• Creation of guidance notes and engineering requirements for conducting field investigations, laboratory testing campaigns, data presentation, result analysis, and geotechnical stability assessments.
• Establishment of guidelines and minimum criteria for the installation of instrumentation, allowing for monitoring of parameters like pore pressures, deformations, water levels, water quality, and more.
• Conducting site characterization, risk analysis, and assessment, along with evaluating alternative solutions, defining performance objectives and indicators, setting criteria, and formulating risk management plans.

Golden Mine Projects is dedicated to an all-encompassing approach to mine planning, a crucial element of ensuring secure tailings management. This comprehensive mine planning approach entails complete coordination of planning activities throughout the entire lifecycle, considering all aspects that can influence the project from its inception, through design, construction, operation, and eventual closure of tailings facilities. These aspects include:

• Engagements and commitments to stakeholders.
• Ore extraction and ore processing.
• Site-wide water management.
• Effective management of other mine-related waste materials such as waste rock.
• Strategies for mine closure.

This integrated mine planning approach encompasses the development and periodic updates of the following:

• Tailings management plans, along with operating and surveillance manuals.
• Identification and establishment of critical controls, trigger action response plans, risk analysis, and risk assessments.
• Definition of performance objectives.
• Continuous review and adjustment of water balances.
• Emergency response and preparedness plans.
• Comprehensive closure plans.

Golden Mine Projects places great importance on assessing performance, which involves the examination of findings from various surveillance activities and reviews, including both internal and independent assessments. These evaluations are conducted to assess:

• The operational performance in relation to predefined performance objectives, indicators, trigger levels, and critical controls.
• Adherence to legal obligations and alignment with established plans and commitments.
• The effectiveness of the risk management process, which may necessitate updates to the risk assessment.
• The necessity for revisions or enhancements to the Operating Maintenance and Surveillance (OMS) manual and other site-specific documents related to tailings management systems. This encompasses an evaluation of the efficiency of surveillance activities and the value of the collected data, as well as the identification of any information gaps.
• The requirement for adjustments or improvements to the Emergency Response Plan (ERP) and Emergency Preparedness Plan (EPP).

Furthermore, at Golden Mine Projects, the outcomes and recommendations resulting from performance assessments are methodically documented and presented on a quarterly basis to senior management and the Board. This practice underscores the critical role of assurance in the performance evaluation process.

Golden Mine Projects has developed guidance notes that define the minimum requirements for:

• Dam break studies. We have developed a framework that can be applied when undertaking dam break studies at Golden Mine Projects Tailings Storage Facility (TSF) sites to enable a consistent and credible assessment of potential failure impacts.
• Field investigations and laboratory testing. We have developed a framework that can be applied when undertaking field investigations and laboratory testing at Golden Mine Projects TSF sites to enable a consistent and credible assessment of potential risks.
• OMS Manuals. Our OMS guidance note aims to provide consistency across the Group and continually work towards optimising tailings facility performance and managing risk.
• Third-party review. Our third-party review guidance note outlines a framework that can be applied when undertaking third-party reviews at Golden Mine Projects TSF sites to enable a consistent and transparent assessment of potential risks.

Golden Mine Projects is deeply committed to ensuring the secure, steady, and sustainable functioning of their Tailings Storage Facilities (TSFs). To accomplish this, the Group TSF Management Guideline has been transformed into a Standard. The Group TSF Management Standard establishes the fundamental prerequisites defined by Golden Mine Projects for TSF management.

The primary objective of this Standard is to outline the minimal prerequisites applicable to TSFs at every stage of their life cycle, starting from initial assessments and site selection, extending through design, operation, and post-closure phases.

The Standard is structured around 10 Topics, each encompassing a set of requirements and deliverables. These 10 Topics are designed to enhance risk management, improve TSF performance, ensure alignment with design specifications, and adhere to legal mandates and corporate policies.

This Standard consists of three main parts:

• Part A - TSF Management Standard: This segment comprises essential practices and principles that must be followed throughout the lifespan of all TSFs within the Group. It serves as the core directive. Attachment A includes the Group Assessment and Audit Criteria.
• Part B - Regional TSF Design and Operational Considerations: This part offers contextual insights into region-specific requirements related to TSF design and operation.
• Part C - Tailings Surveillance Minimum Requirements: This guideline on leading surveillance practices establishes the minimal criteria for an effective surveillance program that supports the secure and efficient management and operation of tailings storage facilities.

Moreover, Golden Mine Projects' management and Board have implemented a comprehensive Integrated and Combined Assurance process. Concerning TSFs, this process encompasses a mandatory independent review of all TSFs at least every three years. The review encompasses all aspects, including operational, sustainable development, and compliance with legal obligations.