B.4 WUG Dual Tunnel Model Results Tunnel Inflows The rock mass inflows from tunnelling have been calculated using an Excel spreadsheet and applies the Perrocet (2005) method for calculating tunnel inflows. A screenshot of the spreadsheet is included in Figure B1. Figure B1 Image of Spreadsheet used to Calculate Groundwater Inflows (Perrocet, 2005) The spreadsheet calculates the inflows and recession flows at each discretized segment (100 m) and accumulates these inflows as the tunnel progresses. The variations in inflow relate to the geological conditions (K and So values), hydraulic head and advancement rate. The tunnel model was then updated to include the inflows at various distances along its length based on the models developed for the vents and fracture zones described below. Vent and Defect Model Results The results of the models for the vent shafts and structural defects are included in Tables B3 and B4. These results were added into the tunnel model at the appropriate distance in the tunnel to produce the final inflow model results shown below. Table B3 Shaft Inflow Assessment Table B4 Dual Tunnel Fracture Inflow Assessment Distance Type Scale L K b ho S Day1 Day7 m m m/s m m m3/d m3/d 347 Lineament Minor 0.5 1.0E-07 258 131 0.001 1.5 0.2 487 Lineament Medium 1 1.0E-06 272 155 0.005 24 3.5 567 Contact Minor 0.5 1.0E-07 222 129 0.001 1.3 0.2 Shaft Location Chainage Depth Diameter Ground Base q Days Q m m m m RL m RL m3/d m3 Shaft 1 Willow Farm 1400 250 3 225 -25 12.5 40 500 Shaft 2 DoC Land 4000 400 3 340 20 23.5 60 1410 Shaft 3 WKP (Egress) 6400 110 3 275 50 13.0 40 520 Shaft 4 WKP (RAR) 6900 200 5 210 60 6.2 40 248 Shaft 5 WKP (FAR) 7000 300 3 215 20 9.8 50 490
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