A BE58 ON AN ILS RWY 04 APCH LANDED WITHOUT A CLRNC ON A RWY WHICH WAS OCCUPIED BY SNOW REMOVAL EQUIP. TWR CTLR WAS NOT AWARE THE BE58 WAS ON THE RWY UNTIL THE PLT TOLD HIM ABOUT THE VEHICLES ON THE RWY.

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I WAS THE LONE TWR CTLR WORKING ALL POS COMBINED. LOW IFR WX WITH HVY SNOW FALL. I HAD NUMEROUS (5-7) SNOW REMOVAL VEHICLES ON RWY 04/22 FOR OVER 3 HRS. THE RWY WAS NOT CLOSED. A BE58 WAS CLRED FOR ILS RWY 04 APCH BY THE RADAR CTLR AND TOLD TO CONTACT THE TWR. AFTER REVIEWING THE AUDIO RECORDING I HEARD THE BE58 HAD CONTACTED THE TWR; RPTING ON FINAL FOR RWY 04. AT THE TIME I DID NOT HEAR THE BE58'S INITIAL CALL TO TWR. THE BE58'S NEXT XMISSION TO TWR WAS 'TWR; DO YOU KNOW YOU HAVE VEHICLES ON THE RWY?' AT THIS POINT I CHKED MY D-BRITE AND OBSERVED NO TFC. I ASSUMED THE BE58 WAS ON SHORT FINAL AND ATTEMPTED TO SEND HIM AROUND. THE BE58 THEN INFORMED ME HE HAD ALREADY LANDED AND WAS AT TAXI SPD ON THE RWY. THE PROB AROSE BECAUSE THE BE58 LANDED WITHOUT CLRNC. CONTRIBUTING FACTORS: 1) I DID NOT HEAR THE BE58'S INITIAL CALL TO TWR ADVISING HE WAS ON FINAL FOR RWY 04. 2) SNOW REMOVAL EQUIP WAS ON THE GND CTL FREQ INSTEAD OF LCL CTL FREQ. 3) ARPT OPERATORS RELUCTANCE TO CLOSE THE RWY WHEN EQUIP WILL BE ON IT FOR EXTENDED PERIODS. FACTORS AFFECTING QUALITY OF HUMAN PERFORMANCE: 1) IT WAS MY FIRST XA00- XH00 LCL SHIFT AFTER 2 DAYS OFF. INCIDENT OCCURRED 7 HRS INTO MY SHIFT AND AFTER I WAS AWAKE FOR 22 HRS STRAIGHT. 2) PLT THOUGHT HE HAD RECEIVED LNDG CLRNC WHEN IN FACT HE HAD NOT. POSSIBLE LACK OF AWARENESS AT XG00 AM AFTER FLYING ALL NIGHT.