Feasibility Study and Technical Report - Pretivm

maximum anticipated airflow volume, the mine air heaters will consume approximately4,000 L of propane each day of the month. At this rate, to maintain supply on site twodelivery truck loads will be required each week.16.9.14 DIESEL STORAGEA storage and delivery system will provide fuel underground for vehicles and equipment.The system will consist of a 20,000 L storage tank located underground in the fuel bayarea. This storage tank will be filled from a 2 in diameter line that connects the storagetank to a 5,000 L batch tank located near the portal. The fuel line will be routed from thesurface batch tank through a bore hole connected to a pipe in the main access tunnel,where it will lead into the fuel storage bay.To fill the underground storage tank, the surface tank will be filled by tank truck and anautomatic valve located on surface is opened, emptying the batch tank by gravity. Theunderground storage tank and batch tank will be fitted with vents to allow air to escapeduring the fuel transfer process. The drain on the surface batch tank will stay open longenough to drain the tank of fuel and allow the connecting 2 in diameter drain line tocompletely empty into the underground storage tank. The fuel line will remain emptyuntil the next fuel transfer is initiated.The surface batch tank will have a volume of 5,000 L, as opposed to the undergroundstorage tank volume of 20,000 L. A completely empty storage tank will require fourcomplete batch tank emptying cycles to fill. A level indicator on the underground storagetank will show the level on an indicator located next to the surface batch tank. Theindicator will be interlocked with the surface valve, allowing the valve to be opened only ifthe level in the underground storage tank is low enough to allow the complete volume ofthe surface batch tank to be emptied into it.A level alarm, located in the underground storage tank, will sound if the level reaches ahigh-high level. Figure 16.32 shows a schematic of the fuel delivery system.Figure 16.32Fuel Line SchematicPretium Resources Inc. 16-70 1291990200-REP-R0012-02.1Feasibility Study and Technical Report on the BrucejackProject, Stewart, BC