Narrative:

Working DR2 and DR3 (southbound and westbound department). Heavy thunderstorm activity and major traffic deviations arrival and departures). I issued 10000' as an altitude for a westbound large transport in order to miss an arrival well west of the STAR at 11000'. When they were clear I issued climb to 17000' to the departure. I was then called for a WX deviation by a southbound departure. I then saw another arrival at 11000' deviating from the STAR converging on the westbound departure who was climbing out of 10300'. I immediately issued 10000' again to the westbound departure, but wound up with less than standard separation. I'm not trying to be evasive when I say I really do not know what the cause of this error is. I was not complacent or inattentive to detail as I was newly checked out and the complexity of the job was greater than normal. All I know for certain (west/O removing the responsibility to know from myself) is that for whatever reason, I was not completely aware that the arrival would be where it was at that time.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION OCCURRED BETWEEN A DEPARTING ACFT AND AN ARRIVING ACFT.

Narrative: WORKING DR2 AND DR3 (SBND AND WBND DEPT). HEAVY TSTM ACTIVITY AND MAJOR TFC DEVIATIONS ARR AND DEPS). I ISSUED 10000' AS AN ALT FOR A WBND LGT IN ORDER TO MISS AN ARR WELL W OF THE STAR AT 11000'. WHEN THEY WERE CLR I ISSUED CLB TO 17000' TO THE DEP. I WAS THEN CALLED FOR A WX DEVIATION BY A SBND DEP. I THEN SAW ANOTHER ARR AT 11000' DEVIATING FROM THE STAR CONVERGING ON THE WBND DEP WHO WAS CLBING OUT OF 10300'. I IMMEDIATELY ISSUED 10000' AGAIN TO THE WBND DEP, BUT WOUND UP WITH LTSS. I'M NOT TRYING TO BE EVASIVE WHEN I SAY I REALLY DO NOT KNOW WHAT THE CAUSE OF THIS ERROR IS. I WAS NOT COMPLACENT OR INATTENTIVE TO DETAIL AS I WAS NEWLY CHKED OUT AND THE COMPLEXITY OF THE JOB WAS GREATER THAN NORMAL. ALL I KNOW FOR CERTAIN (W/O REMOVING THE RESPONSIBILITY TO KNOW FROM MYSELF) IS THAT FOR WHATEVER REASON, I WAS NOT COMPLETELY AWARE THAT THE ARR WOULD BE WHERE IT WAS AT THAT TIME.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.