FTB Unleashed started crashing when I try to open my smeltery. It was running fine until tonight. I did just start a 64*64 block quarry but it had been running fine for about two hours. I had optifine installed but I removed it and it still crashed. Optifine was the only additional mod I had installed. I don't want to mess around with it too much for fear of breaking my world. I'll attach the crash file. Any assistance would be most welcome.