S56 APCH CTLR EXPERIENCED OPERROR WHEN HE DID NOT OBSERVE A POINTOUT ON TFC ENTERING HIS AIRSPACE AND THEN FAILED TO BRIEF HIS RELIEF OF THE CONFLICTING TFC.

Narrative

DURING THE BUSIEST BANK OF THE DAY; THERE WAS VARIABLE WX CONDITIONS FROM SNOW SHOWERS TO CLR VFR MOVING ACROSS THE AIRSPACE. I WAS HOLDING A C421 OVER THE TCH VOR WHICH PUT HIM OVER THE ARPT AT FL210. THIS KEPT HIM OUT OF EVERYONE ELSE'S AIRSPACE WHILE THEY WERE EXTREMELY BUSY. AN ARR SECTOR COORDINATED A 'POINTOUT' FOR A W ARR TO FOLLOW A HVY ON THE DOWNWIND. I APPROVED THE POINTOUT. I DID NOT OBSERVE THE ACFT XING INTO MY AIRSPACE. TYPICALLY; THIS KIND OF POINTOUT IS FOR AN ACFT THAT IS RIDING CLOSE TO THE AIRSPACE LINE. A WBOUND DEP DEPARTED SLC. I TOLD HIM RADAR CONTACT AND ASSIGNED AN ALT BELOW THE FULL DOWNWIND. THEN MY RELIEF PLUGGED IN. I BRIEFED HIM ABOUT THE WX AND THE DEP AND EXTENSIVELY ABOUT THE HOLDING C421. SINCE I DID NOT SEE THE POINTED OUT ACFT AT THAT TIME OR EARLIER; I DID NOT INCLUDE IT IN THE RELIEF BRIEFING. THE NEW CTLR STATED HE HAD NO QUESTIONS AND ASSUMED THE RESPONSIBILITY FOR THE POS. AS THE DEP CROSSED UNDER THE DOWNWIND; I TOLD HIM 'YOU CAN CLB THE DEP;' WHICH HE DID. I UNPLUGGED AND TURNED AWAY. HE CALLED ME BACK ASKING WHAT THIS OTHER (THE POINTOUT) ACFT WAS DOING. HE STOPPED THE CLB AND GOT VISUAL SEPARATION; BUT STANDARD SEPARATION HAD ALREADY BEEN LOST. I; FIRST OF ALL; SHOULD NOT HAVE APPROVED SUCH A 'WIDE OPEN' POINTOUT. I SHOULD HAVE WORKED AN ACFT THAT WOULD BE XING THE MIDDLE OF MY AIRSPACE. I SHOULD HAVE MADE A REMINDER NOTE FOR THE POINTOUT AND PUT IT IN FRONT OF ME. ALSO; IF I WOULD HAVE STAYED PLUGGED IN ON THE POS A LITTLE LONGER; I MAY HAVE BEEN ABLE TO CATCH THE SIT BEFORE THE LOSS OF SEPARATION.