S80 IS CLRED INTO POS AND HOLD FOR DEP ORD RWY 32L AT INTXN T10 WITH A B747 ALREADY IN POS ON RWY 32L AT APCH END. CAPT DOES NOT PROCEED ONTO RWY UNTIL TKOF CLRNC IS ISSUED.

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TWR CLRED US INTO POS AND HOLD ON RWY 32L AT T10. AS WE APCHED THE RWY; I NOTICED A B747 AT THE VERY END OF RWY 32L IN POS WITH NOSE LIGHTS ON. WE TRIED TO ASK TWR ABOUT THE B747 AND HE CLIPPED OUR XMISSION TO TELL THE ACFT BEHIND US TO GO INTO POS. I DELAYED SLIGHTLY MY TURN TO LINE UP WITH THE RWY TO VERIFY AS MUCH AS I COULD AND NEEDED THAT THE B747 WAS STAYING IN POS. I DO NOT KNOW HOW LONG THE B747 WAS THERE. HE MAY ACTUALLY BE ON A SEPARATE TWR FREQ. I CAN ACCOUNT FOR 6 ACFT THAT TWR TALKED TO AND HE NEVER MENTIONED THE B747 AT THE END IN POS. WITH ALL THE NEED TO BE AWARE OF RWY PROBS; I WOULD THINK THAT THIS NEEDS SOME HELP. I THOUGHT ATC SHOULD HAVE SAID SOMETHING. ALSO I ASK MYSELF WAS THERE A REAL NEED THAT THE B747 TO BE IN POS ON THE RWY TO BEGIN WITH. I THINK HE WAS THERE AWHILE. LAST; IF WE ARE ON 2 DIFFERENT TWR FREQS ON RWY 32L; I FEEL THIS IS A POTENTIAL PROB. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR CALLED TWR SUPVR ON RETURN TO ORD AN LEARNED THAT 2 SEPARATE CTLRS HAVE CTL AUTH TO UTILIZE RWY 32L; 1 CTLR FOR OPS N OF RWY 9R/27L; THE OTHER FOR OPS S OF RWY 9R/27L. THE SUPVR ADVISED THAT THE CTLR SHOULD HAVE ADVISED ACFT CLRED ONTO RWY 32L AT T10 OF TFC HOLDING ON THE APCH END OF THE RWY.