Feasibility Study and Technical Report - Pretivm

Table 13.13 SMC Test Results (2012)SampleIDDWi(kWh/m 3 ) A b AxbMia(kWh/t)Mih(kWh/t)Mic(kWh/t)taSpecificGravityVOK HW 1 5.76 52.8 0.92 48.6 16.7 12.0 6.2 0.45 2.79VOK Ore 1 6.37 56.6 0.77 43.6 18.1 13.2 6.8 0.41 2.79VOK Ore 3 7.12 62.9 0.62 39.0 20.2 15.0 7.8 0.40 2.75VOK Ore 5 4.61 52.3 1.16 60.7 13.9 9.5 4.9 0.56 2.81WZ HW 1 4.89 55.2 1.08 59.6 14.1 9.8 5.1 0.53 2.90WZ Ore 2 7.08 66.7 0.59 39.4 19.9 14.8 7.7 0.37 2.76WZ Ore 4 6.32 69.9 0.62 43.3 18.3 13.3 6.9 0.41 2.75Average 6.02 59.5 0.82 47.7 17.3 12.5 6.5 0.44 2.79Average – VOK 5.97 56.2 0.87 48.0 17.2 12.4 6.4 0.45 2.79Average – WZ 6.10 63.9 0.76 47.4 17.4 12.6 6.6 0.44 2.80Note: DWi = drop weight index; Mia = coarse ore work index provided directly by SMC Test®; Mih = highpressure grinding roll (HPGR) ore work index provided directly by SMC Test®; Mic = crushing work indexprovided directly by SMC Test® ta =low-energy abrasion component of breakageContract Support Services, Inc. conducted primary grinding circuit simulations based onthe test results from Hazen and Inspectorate. The simulation results for a mill feed rateof 2,700 t/d are summarized as follows:• SAG mill/ball mill/pebble crusher (SABC) arrangement: a 19 ft diameter by 8 ft long (effective grinding length (EGL)) SAG with1,290 kW of installed power a 13 ft diameter by 22 ft long ball mill with 1,470 kW of installed power(drawing 1,417 kW) a pebble crusher with 45 to 50 kW of installed power.• SAG mill/ball mill (SAB) arrangement: a 19 ft diameter by 8 ft long (EGL) SAG with 1,290 kW of installed power a 13 ft diameter by 22 ft long ball mill with 1,470 kW of installed power(drawing 1,429 kW).13.3.7 SAMPLE SPECIFIC GRAVITYThe specific gravity of the Brucejack mineral samples are shown in Table 13.14 andTable 13.15. The specific gravity data varied narrowly from 2.71 to 2.87.Pretium Resources Inc. 13-11 1291990200-REP-R0012-02Feasibility Study and Technical Report on the BrucejackProject, Stewart, BC