SECTION 3 Site Investigations & Results C:\D Data\GWS C Drive\GWS\Client Files\1344 OGL - WKP\4 Deliverables\WKP Final Draft Report\June Report\WAI-985-000-REP-LC-0030. Final_Rev_0.docx 18 Throughout the exploration drilling process records were kept of the depth at which drilling water circulation was lost and where zones required grouting to enable drilling to continue. Analysis of these records indicates that zones of water loss that required grouting were generally associated with the stockworks vein systems in the upper part of the boreholes, with the occasional losses due to discrete open veins or large fractures with higher-than-average permeability. 3.4 Piezometer Installation Two sets of standpipe piezometers, each having a shallow and deep well setting, have been constructed at the site details of which are included in Table 1. The locations are shown in Figure 19. Groundwater was first encountered at a depth of 7 m in polymictic ignimbrite at Drill Site 1 and at 35 m depth in ignimbrite breccia at Drill Site 5. These piezometers indicate a vertically downward hydraulic gradient in the range of 0.55 to 0.59 m/m. Table 1 Standpipe Piezometer Details Piezo Lithology Elevation (m RL) Collar Height (m) Collar Elevation (m RL) Screen Depth (m) Groundwater Depth (m) Groundwater Elevation (m RL) WKP01S Pyroclastics 181.66 0.25 181.91 12.50 15.50 6.93 171.4 WKP01D Rhyolite 181.66 0.60 182.26 42.50 45.50 23.32 138.2 WKP02S Pyroclastics 225.77 0.35 226.12 38.60 41.60 34.97 190.0 WKP02D Rhyolite 225.77 0.40 226.17 64.90 67.90 50.39 172.1 At drillholes WKP-P03D, WKP-P04 and WKP-P05D, nested completions of vibrating wire piezometers were installed. The details of these piezometers are included in Table 2. Based on these observations from WKP-03D there is a vertical gradient of 0.14 between the Andesite and Rhyolite rock units and approximately 0.02 between the Rhyolite and the T-Stream Vein. A temporal record of the groundwater pressures over time is included in Figure 20. The vein piezometer tip VWP03 shows some response to rainfall and the magnitude of the response allows an estimate of vein Storativity of around 0.01. Table 2 Vibrating Wire Piezometer Details Piezo Lithology Installation Depth (m) Actual Depth (m RL) Groundwater Elevation (m RL) WKP-03D Weathered Andesite 51 223 234.5 WKP-03D Competent Rhyolite 131 163 163.6 WKP-03D T Stream Vein 199 111 112.7 WKP-04D Weathered Rhyolite 57 131 140.1 WKP-04D EG Vein 273 -50 98.6 WKP-04D Footwall Zone 363 -120 42.6 WKP-05D Competent Andesite 135 139 240.6 WKP-05D Competent Pyroclastics 205 69 233.8 WKP-05D Competent Rhyolite Flow 265 9 194.3
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