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On 12/28/2008 at 0445 the C-337 unit 5 cel … On 12/28/2008 at 0445 the C-337 unit 5 cell 3 PGLD (process gas leak detection) head located on stage 8 actuated. Operators responded to the alarm and performed sampling in the area. The sample result indicated 3 ppm of HF at the stage 8 compressor. To stop the release the cell was taken off-stream and the pressure was reduced to below atmosphere. Investigation indicated that a UF6 release had occurred. The amount of material released has not been determined.</br>The actuated PGLD head is Q safety system component. At the time of the incident the cell was operating in a mode which required the system to be operable. This is being reported based on SAR 6.9 Table 1, J.2 as an Unplanned Actuation of a Q Safety System.</br>The NRC Senior Resident Inspector has been notified of this event.</br>The licensee states that a compressor seal appears to have failed. The amount of material released is characterized as on the order of a few grams. Material release was only in the vicinity of the compressor. There was nothing unusual or not understood and all systems functioned as required. There was no offsite release or personnel contamination resulted from this event.</br>* * * RETRACTION PROVIDED ON 02/06/09 AT 1427 FROM BEASLEY TO KLCO * * *</br>A subsequent review by USEC Regulatory Affairs concluded that the UF6 Release Detection System detectors installed 'above the `B' seals on the axial flow compressors' (SAR 3.3.5.9.5), and the detectors for the instrument cubicles do not 'prevent or mitigate the consequences of postulated accidents that could result in a member of the general public located offsite being exposed to EG (Evaluation Guidelines)-1 or EG-2 guideline values' (SAR 4.2.2). Therefore, they do not meet the criteria to be classified as 'Q' (SAR 4.2.2).</br>The safety equipment actuation reporting criteria (SAR 6.9-1 J.2) requires NRC to be notified of actuations of "Q" systems resulting from events that have the potential for significant impact on the health and safety of personnel, which are defined in the criteria as those events where actual plant conditions existed that the system was designed to protect against. Since the referenced UF6 Release Detection System detectors do not meet the criteria to be classified as "Q" and do not protect against a postulated accident that could result in a member of the general public being exposed to EG-1 or EG-2 guideline values, the actuations would not be reportable under this criteria.</br>Summary:</br>- the B-end seal PGLD (Process Head Leak Detector) head is not required to be 'Q'</br>- the postulated release from the B-end seal cavity does not have significant impact on personnel.</br>- A release from the B-end seal cavity is not a condition that the PGLD system is designed to protect against.</br>The NRC Senior Resident Inspector has been notified of this event retraction.</br>Notified R2DO (Rudisail) and NMSS (Kotzalas).ified R2DO (Rudisail) and NMSS (Kotzalas).
10:45:00, 28 December 2008 +
44,744 +
13:59:00, 28 December 2008 +
10:45:00, 28 December 2008 +
On 12/28/2008 at 0445 the C-337 unit 5 cel … On 12/28/2008 at 0445 the C-337 unit 5 cell 3 PGLD (process gas leak detection) head located on stage 8 actuated. Operators responded to the alarm and performed sampling in the area. The sample result indicated 3 ppm of HF at the stage 8 compressor. To stop the release the cell was taken off-stream and the pressure was reduced to below atmosphere. Investigation indicated that a UF6 release had occurred. The amount of material released has not been determined.</br>The actuated PGLD head is Q safety system component. At the time of the incident the cell was operating in a mode which required the system to be operable. This is being reported based on SAR 6.9 Table 1, J.2 as an Unplanned Actuation of a Q Safety System.</br>The NRC Senior Resident Inspector has been notified of this event.</br>The licensee states that a compressor seal appears to have failed. The amount of material released is characterized as on the order of a few grams. Material release was only in the vicinity of the compressor. There was nothing unusual or not understood and all systems functioned as required. There was no offsite release or personnel contamination resulted from this event.</br>* * * RETRACTION PROVIDED ON 02/06/09 AT 1427 FROM BEASLEY TO KLCO * * *</br>A subsequent review by USEC Regulatory Affairs concluded that the UF6 Release Detection System detectors installed 'above the `B' seals on the axial flow compressors' (SAR 3.3.5.9.5), and the detectors for the instrument cubicles do not 'prevent or mitigate the consequences of postulated accidents that could result in a member of the general public located offsite being exposed to EG (Evaluation Guidelines)-1 or EG-2 guideline values' (SAR 4.2.2). Therefore, they do not meet the criteria to be classified as 'Q' (SAR 4.2.2).</br>The safety equipment actuation reporting criteria (SAR 6.9-1 J.2) requires NRC to be notified of actuations of "Q" systems resulting from events that have the potential for significant impact on the health and safety of personnel, which are defined in the criteria as those events where actual plant conditions existed that the system was designed to protect against. Since the referenced UF6 Release Detection System detectors do not meet the criteria to be classified as "Q" and do not protect against a postulated accident that could result in a member of the general public being exposed to EG-1 or EG-2 guideline values, the actuations would not be reportable under this criteria.</br>Summary:</br>- the B-end seal PGLD (Process Head Leak Detector) head is not required to be 'Q'</br>- the postulated release from the B-end seal cavity does not have significant impact on personnel.</br>- A release from the B-end seal cavity is not a condition that the PGLD system is designed to protect against.</br>The NRC Senior Resident Inspector has been notified of this event retraction.</br>Notified R2DO (Rudisail) and NMSS (Kotzalas).ified R2DO (Rudisail) and NMSS (Kotzalas).
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00:00:00, 6 February 2009 +
GDP-1 +
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13:59:00, 28 December 2008 +
0.135 d (3.23 hours, 0.0192 weeks, 0.00442 months) +
10:45:00, 28 December 2008 +
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