Supporting Technical Assessments

R J Hill Laboratories Limited 28 Duke Street Frankton 3204 Private Bag 3205 Hamilton 3240 New Zealand 0508 HILL LAB (44 555 22) +64 7 858 2000 [email protected] www.hill-laboratories.com T T E W This Laboratory is accredited by International Accreditation New Zealand (IANZ), which represents New Zealand in the International Laboratory Accreditation Cooperation (ILAC). Through the ILAC Mutual Recognition Arrangement (ILAC-MRA) this accreditation is internationally recognised. The tests reported herein have been performed in accordance with the terms of accreditation, with the exception of tests marked * or any comments and interpretations, which are not accredited. Certificate of Analysis Page 1 of 2 Client: Contact: Mark Burroughs C/- Oceana Gold (New Zealand) Limited PO Box 190 Waihi 3610 Oceana Gold (New Zealand) Limited Lab No: Date Received: Date Reported: Quote No: Order No: Client Reference: Submitted By: 2854592 04-Feb-2022 14-Feb-2022 85959 70057893 Extended suite Jake Horne SPv1 Sample Type: Aqueous Sample Name: Lab Number: 1839223 03-Feb-2022 1839224 03-Feb-2022 2854592.1 2854592.2 2854592.3 1839225 03-Feb-2022 Individual Tests pH Units 2.0 2.2 3.3 - - pH g/m3 as CaCO3 2,500 3,900 340 - - Acidity (pH 3.7) g/m3 as CaCO3 < 1.0 < 1.0 < 1.0 - - Total Alkalinity mS/m 550 785 534 - - Electrical Conductivity (EC) g/m3 150 390 123 - - Dissolved Aluminium g/m3 0.0034 0.0050 < 0.0010 - - Dissolved Antimony g/m3 < 0.005 < 0.005 0.024 - - Dissolved Barium g/m3 61 470 500 - - Dissolved Calcium g/m3 0.32 1.79 2.3 - - Dissolved Cobalt g/m3 1,170 750 141 - - Dissolved Iron g/m3 15.3 121 460 - - Dissolved Magnesium g/m3 4.2 57 9.7 - - Dissolved Manganese g/m3 < 0.00015 < 0.00015 < 0.00008 - - Dissolved Mercury g/m3 0.0128 0.0053 < 0.0010 - - Dissolved Molybdenum g/m3 1.2 6.2 78 - - Dissolved Potassium g/m3 0.008 0.013 0.038 - - Dissolved Selenium g/m3 < 0.0005 0.0010 < 0.0005 - - Dissolved Silver g/m3 2.3 8.0 63 - - Dissolved Sodium g/m3 0.121 0.50 2.5 - - Dissolved Strontium g/m3 0.029 0.178 0.117 - - Dissolved Uranium g/m3 0.23 0.159 0.048 - - Dissolved Vanadium g/m3 2,600 7,500 4,200 - - Sulphate Heavy metals, dissolved, trace As,Cd,Cr,Cu,Ni,Pb,Zn g/m3 50 30 0.29 - - Dissolved Arsenic g/m3 0.0072 0.033 0.0122 - - Dissolved Cadmium g/m3 0.46 0.69 0.072 - - Dissolved Chromium g/m3 1.76 5.1 9.3 - - Dissolved Copper g/m3 < 0.0005 < 0.0005 0.0066 - - Dissolved Lead g/m3 0.121 0.62 1.49 - - Dissolved Nickel g/m3 8.4 25 5.5 - - Dissolved Zinc The following table(s) gives a brief description of the methods used to conduct the analyses for this job. The detection limits given below are those attainable in a relatively simple matrix. Detection limits may be higher for individual samples should insufficient sample be available, or if the matrix requires that dilutions be performed during analysis. A detection limit range indicates the lowest and highest detection limits in the associated suite of analytes. A full listing of compounds and detection limits are available from the laboratory upon request. Unless otherwise indicated, analyses were performed at Hill Laboratories, 28 Duke Street, Frankton, Hamilton 3204. Summary of Methods Sample Type: Aqueous Test Method Description Default Detection Limit Sample No

RkJQdWJsaXNoZXIy MjE2NDg3