ZOB CTLR INVOLVED IN OPERROR IN COMPLEX ARR DEP TFC SIT.

Narrative

I WAS WORKING AN ARR AND A DEP SECTOR (YNG). THE SECTOR DOES BOTH. I WAS WORKING AN ARR PUSH AS WELL AS A DEP RUSH AT THE SAME TIME. THERE WERE 4 OVERFLTS PASSING THROUGH THE SECTOR DURING THIS TIME. I HAVE WORKED THIS SECTOR FOR 10 YRS AND CAN SAY THAT THIS WAS PROBABLY THE BUSIEST I HAVE BEEN. THERE WAS A RADAR ASSOCIATE HELPING AND ANOTHER PERSON STUFFING STRIPS. A SUPVR WAS ALSO WATCHING FROM BEHIND. WHILE SPACING THE 2 TURBOPROPS AND DSNDING A JET (Z) ON TOP OF THEM; I WAS DISTR BY THE DEPS. CLE APCH IS REQUIRED TO GIVE US 5 MI IN TRAIL (CONSTANT OR INCREASING). MY ATTN WAS TAKEN AWAY FROM SPACING THE ARRS TO TRY TO MAINTAIN SEPARATION OF THE DEPS. ACFT #1 WAS FIRST IN ARR SEQUENCE. ACFT #2 WAS BEING VECTORED FOR SPACING AND THEN CLRED DIRECT TO NAVAID WHEN SPACING WAS ACHIEVED. A JET (Z) WAS BEING STEPPED DOWN ON TOP. ACFT #1 (AT 9000 FT) ACFT #2 (DSNDING TO 9000 FT) WAS APPROX 6-7 MI IN TRAIL. ACFT #3 (JET BEING STEPPED DOWN) WAS ON TOP OF #2 AND #1. JET ACFT (Z) AUTO HANDED OFF TO CLE APCH WITH DATA BLOCK NOT SHOWING WHAT ACFT WAS DOING (150T 125). CONFLICT ALERT ACTIVATED WITH ALL 3 DATA BLOCKS FLASHING. COMMON OCCURRENCE WITH JET DSNDING THROUGH WHAT COMPUTER THOUGHT WAS ASSIGNED ALT. I ATTRIBUTED THE FLASHING AT FIRST TO JUST THIS. I WAS DISTR TO DEPS COMING OUT AND TRYING TO SEPARATE OR UNDERSTAND WHAT WAS HAPPENING WITH THEM. AN EMBRAER JET WAS IN FRONT OF A B737 WITH 5 AND 6 MI SEPARATION AND DECREASING. EMBRAER JET CHKED ON FREQ DEPARTING 11400 FT FOR 12000 FT. B737 WAS ALREADY LEVEL AT 12000 FT BEHIND WITHOUT COM XFER. WHEN I ATTEMPTED TO SUPPRESS CONFLICT ALERT WITH ACFT ON ARR; I NOTICED THAT NOT ONLY THE JET BEING STEPPED DOWN ON TOP OF ACFT #1 AND #2 WERE FLASHING; BUT ALSO ACFT #1 AND #2 WERE IN CONFLICT. I IMMEDIATELY ISSUED A TURN TO ACFT #2; BUT DUE TO FREQ CONGESTION; IT TOOK ANOTHER XMISSION BEFORE ACFT INVOLVED WERE TURNED AND SEPARATION WAS LOST. IT TOOK ANOTHER 5-10 MINS BEFORE I COULD RELINQUISH CTL TO RELIEVING CTLR. THERE WERE BTWN 19-23 DATA BLOCKS ON SCOPE AT THAT TIME. ADDITIONAL DEP IN TRAIL SPACING COULD HAVE HELPED PREVENT OPERROR IN MY OPINION.