The 2 Ore Silos help prevent Ore Trucks from going behind the Ore Refinery.

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Select truck and press S after it unloads at the refinery to make the truck mine the closest ore, but if you press S while the truck is going to the Ore Refinery then it will stop moving. If it stops then point it to the ore and press S again and it will be back on its way to the ore refinery. Look at these 4 examples below to learn how ore trucks mine. Top Left is the best position, because you will never have to S your trucks.

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