EGL Ref: 9215 23 June 2022 Page 31 This report shall only be read in its entirety. File: WAI-985-000-REP-LC-0002_Rev0.docx. • Monitoring of materials and construction standards to ensure that the Contract Specification is adhered to. Storage 2 has piezometers installed along six lines through the embankment, within two gullies, and at an intermediate location. Six vibrating wire piezometers were installed in the tailings in June 2010 and six in May 2017. Storage 1A, has piezometers installed in the embankment on seven sections. Subsurface and leachate drains are measured at the sumps. Storage 2 is measured manually and Storage 1A is measured using installed flow meters. Measurements are taken approximately every fortnight. Benchmarks are installed on the berms following rehabilitation to allow measurement of the deformation of the outside shoulder of the embankment. A total of 19 benchmarks have been installed on Storage 1A and 39 on Storage 2. Control testing to confirm the specified standards for the different zones is undertaken. Earthworks QA/QC was initially undertaken by Waihi Gold staff. Since November 1998 it has been undertaken by an independent testing agency (Geotechnics Ltd). Geotechnics has an on-site laboratory. During construction EGL undertakes regular site visits and provides technical assistance to mine staff who are responsible for supervising construction. The data from the monitoring and surveillance programme are provided to the Designer, EGL, at regular intervals for review. The performance of Storage 2 and Storage 1A is formally assessed annually by EGL. This involves review of monitoring and surveillance data collected and construction records, a site inspection and stability analyses for the asbuilt profile and conditions. The reviews are presented in annual inspection reports. The data and annual inspection report are provided annually to Waikato Regional Council and Hauraki District Council and are independently peer reviewed by the Peer Review Panel. 4.8. Peer review A Peer Review Panel (PRP) has been in existence since commencement of the project. The panel includes technical specialists who between them have expertise in geochemistry, geotechnical engineering with recognised experience in design and construction of tailings storage facilities, hydrology, and rehabilitation. The specialist dam and geotechnical engineers have been H. Kennedy, Dr L. Wesley and currently D. Tate. The primary function of the PRP is to ensure that the conditions of design, construction, operation, and maintenance are met and that such work is undertaken by appropriately qualified personnel in accordance with good practice. They review designs and the Annual Inspection Reports and undertake an annual site inspection and a formal meeting with Waikato Regional Council, Hauraki District Council, OGNZL and consultants. Their role as design reviewers is in addition to the design review process required by the Building Act. The Building Act requirements for independent review of design did not exist at the time of design of Storage 2. A Comprehensive Dam Safety Review (CDSR) of Storage 1A and 2 was undertaken by T. Pickford in 2020 (Ref. 14). A CDSR is a comprehensive review of the design, construction,
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