Governance, standards and guidelines

At Gold Fields, tailings management plans involve developing documents and plans related to tailings management and updating these documents and procedures as appropriate throughout the lifecycle, aligning with corporate policy. This includes developing and updating as appropriate:

• A detailed construction management plan, including a construction quality plan and assurance protocols that document that construction meets the design intent.
• Closure plan
• Design Basis Report, water balance and water management plan, tailings transportation, and deposition plan.
• Guidance notes and engineering requirements for field investigations, laboratory testing campaigns, presentation of data and results, and geotechnical stability.
• Guidance notes and minimum requirements for installing instrumentation to allow for the monitoring of pore pressures, deformations, water levels, water quality, etc.
• Site characterisation, risk analysis and assessment, evaluation of alternatives, performance objectives, indicators, criteria, and risk management plans.

Gold Fields is committed to an integrated approach to mine planning, which is essential to safe tailings management. Integrated mine planning involves the full integration of planning across the lifecycle of all aspects that can impact the project conception, design, construction, operation, and closure of tailings facilities, including:

• Commitments to stakeholders
• Ore extraction and ore processing
• Site-wide water management
• Management of other mine wastes such as waste rock
• Mine closure

Integrated mine planning includes developing and updating as appropriate:

• Tailings management plans and operating and surveillance manuals
• Critical controls, trigger action response plans, risk analysis, and risk assessments
• Performance objectives
• Water balances (updated and calibrated)
• Emergency response and preparedness plans
• Closure plans

At Gold Fields, performance evaluation includes results of surveillance and reviews, both internal and independent, to evaluate:

• Operating performance against performance objectives and indicators, trigger levels, and critical controls
• Compliance with legal requirements, and conformance with plans and commitments
• The risk management process, including the need to update the risk assessment
• The need for changes or updates to the Operating Maintenance and Surveillance (OMS) manual or other site-specific tailings management system-related documents. This includes evaluating the effectiveness of surveillance activities and the utility of the information being collected, identifying any gaps in information collection
• The need for changes or updates to the Emergency Response Plan (ERP) and Emergency Preparedness Plan (EPP)

At Gold Fields, the results and recommendations arising from performance evaluations are documented and reported every quarter to senior management and the Board, as assurance is a critical component of performance evaluation.

Gold Fields 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 Gold Fields 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 Gold Fields 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 Gold Fields TSF sites to enable a consistent and transparent assessment of potential risks.

Gold Fields is committed to the safe, stable, and sustainable operation of their TSFs, and to achieve this, the Group TSF Management Guideline has been converted to a Standard. The Group TSF Management Standard sets the minimum Gold Fields requirements for managing TSFs.

The purpose of the Standard is to define the minimum requirements for TSFs throughout their lifecycle, from early studies and site selection, through design, operation, and post-closure.

This Standard provides a framework for safe tailings facility management while affording the regions and sites flexibility regarding how best to achieve this goal. Unless otherwise specified, the requirements of the Standard are directed to the sites but, in many cases, will require significant external input from our Engineers of Record and specialist consultants.

The Standard is underpinned by 10 Topics comprising a list of requirements and deliverables. The 10 Topics are intended to facilitate improved risk management and TSF performance, achieve the design intent, and meet legal requirements and corporate policy.

The new Standard includes greater governance and accountability than was previously required.

This Standard comprises three parts, namely:

• Part A - TSF Management Standard: consists of leading practices and principles which must be adhered to during the life cycle of all TSFs in the Group. This part of the Standard consists of the core directives. The Group Assessment and Audit Criteria are included in Attachment A.
• Part B - Regional TSF Design and Operational Considerations: provides some background to regional specific requirements associated with the design or operation of TSFs.
• Part C - Tailings Surveillance Minimum Requirements: This leading practice surveillance guideline defines the minimum requirements for an effective surveillance program supporting the safe and efficient management and operation of tailings storage facilities.

In addition, the management and Board of Gold Fields have a comprehensive Integrated and Combined Assurance process in place, which, in the case of TSFs, consists of a minimum 3-yearly independent review of all TSFs. The review covers all operational, sustainable development, and legal aspects.