ML071560232
| ML071560232 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 06/04/2007 |
| From: | - No Known Affiliation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| CR-PNP-2005-05471 | |
| Download: ML071560232 (1) | |
Text
Follow-Up to CR-PNP-2005-0547 1 Procedure 8.E. 19 Issue Condition
Description:
A concern was identified during the NRC 9/18/2006 through 9/22/2006 inspection for license t-enewal concerning the refuel floor bellows leak detection alarm failure disaovered in December 2005.
This condition was identified in CR-2005-05471: During performance of 8.E.19 ATT1, step 6 for FS-4803 when water was poured in test connection (approximately 1 1/2 gallons) the water filled up the test line and did not drain and FS-4803 did not actuate. It appears that this CR was closed by CRG as a Cat. D with a WRT (09001 8)/MR06100047, stating that this line is clogged and needs to be unclogged so testing can be completed. The work to address this condition is scheduled for February 2007. A past operability evaluation and the cause of the clogging was not conducted.
I Immediate Action:
The Pilgrim team evaluated if the failure of the FS-4803 (the alarm being nonfunctional or test line blockage) could have impacted the condition of the drywell exterior surfaces prior to discovery of the condition described above. The condition is only a concern with water above the refueling bellows. The only time this occurred since the previous satisfactory test of the alarm was during RFO15.
If the 3 drain line was blocked, any leakage-from the refuel floor bellows could spill onto the ledge at Elevation 89 11 directly under the refueling bellows and into the four 34 tell-tale lines where it would be detected at the floor drains on elevation 74. The water collected in the floor drains would likely have been noticed by operators during their daily walk-down of Elevation 74 and they would have reported the condition for corrective actions. A CR search was conducted for the past five years using keywords = floor drain 74 or 74 and no hits were found. Another search with keywords = floor drain provided 106 hits. None of these hits was for leakage found at the floor drains on Elevation 74.
==
Conclusion:==
Because the tell-tale drains will indicate bellows leakage during refueling operations, failure of the alarm would not allow leakage that is undetected. No leakage was observed during the period that the alarm was potentially nonfunctioning. Therefore, the alarm failure had no impact on the condition of