Assurance is an oversight process to provide an outside perspective on whether tailings are managed effectively and responsibly. It is distinct from the Performance Evaluation component of a tailings management system and crosscuts all other tailings management aspects.

Effective assurance is a valuable feedback mechanism for those directly involved in tailings management. Depending on the mechanism used, assurance potentially provides perspectives on current performance, deficiencies, opportunities for improvement, future plans, and other tailings management aspects.

Gold Fields utilises the following mechanisms to provide assurance:

Audits in general

Audits evaluate and report on the degree of conformance with stipulated criteria based on the systematic collection and documentation of relevant evidence. Audits involve some degree of judgment but are not designed to determine the root cause of deficiencies or evaluate management system effectiveness.

Engineer of Record (EoR)

We retain an Engineer of Record (EoR) for most of our active sites. As of January 2022, our EoRs are employed by the following companies: Golder (4 TSFs), Stantec (1 TSF), SRK Consulting (1 TSF), Knight Piesold (4 TSFs), SLR Consulting (8 TSFs), Tetra Tech (5 TSFs) and CMW Geosciences (8 TSFs).

The EoRs are responsible for reviewing and approving all engineering and design data, associated operating and monitoring procedures, as-built drawings, and facility inspections to confirm physical integrity, safety, the performance of the facility, and ancillary structures.

The EoRs define the parameters and specifications for construction and operations such as embankment and dam slope angle, allowable rate of rise, construction and operational material quality and methods, and the dam's phreatic surface level and and minimum freeboard requirements.

Group TSF Management Standard reviews

A comprehensive third-party review covering operational, legal aspects, and sustainable development must be carried out every three years. This review also checks the operation's ongoing compliance against the Group TSF Management Standard and applicable design guidelines.

Facilities that have an "Extreme" consequence rating must have this third-party operational review carried out on an annual basis.

Regulatory reviews

Legal and regulatory compliance audits are typically carried out annually to check compliance against permits and operating licenses. The frequency of these audits might differ for operations in Ghana and Peru.

Local regulations may also require operations to regularly undertake third-party reviews with a report on the findings required to be submitted to various governmental agencies. For example, Ghana requires quarterly third-party operational reviews to be conducted and reported.

Independent Review

Third-party reviews are most effective if they begin at the project conception and continue through the design, construction, operation, and closure stages. As such, the intent of a third-party review is to identify and address potential deficiencies before they occur and is fundamentally a preventative risk control measure. The preventative focus of third-party reviews fosters continual improvement and mitigates complacency.