05000237/FIN-2011002-01
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Finding | |
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| Title | Satisfactory Performance of a Surveillance Test Procedure That Was Later Demonstrated to be Not Capable of Being Performed |
| Description | The inspectors identified a non-cited violation (NCV) of the Dresden Nuclear Power Station Renewed Facility Operating License having very low safety significance (Green) for the licensees failure to perform adequate post-maintenance testing (PMT) on one smoke detector in the Control Room Ventilation System ductwork. During a walkdown of the Control Room Ventilation System, the inspectors identified that three smoke detectors in the ventilation ducts had been replaced in June 2010 and one was never tested successfully upon its return to service. During the course of this inspection, the inspectors identified several procedure quality issues. The inspectors reviewed WO 902046-01,D2/3 Annual PM Control Room HVAC System Smoke Detector Test, performed on November 25, 2008. This work order was to perform surveillance test DFPS 4183-14, Unit 2/3 Control Room HVAC Smoke Detector Annual Surveillance Procedure, Revision 9. The test results identified that Alarm 2/3-2223-89-C1, Control Room/East Turbine Building Smoke Detector Trouble, would not alarm when the following detectors were sprayed with test gas: Fn2/3-8941-017, Located in the Control Room Main Return Duct; Fn2/3-8941-018, Located in the Control Room HVAC Equipment Room Train B Exhaust Duct; and Fn2/3-8941-013, Located on the Main Control Room HVACX outside air supply duct. The 2/3-2223-89-C1, Control Room/East Turbine Building Smoke Detector Trouble, alarms at Panel 2/3-2223-89 in the Unit 2 switchgear room if a detector loses power. Other alarms at Panel 2/3-2223-89 and in the Control Room alarmed when the detectors were sprayed with test gas. The licensee wrote Issue Report (IR) 849580, Problems Encountered during Performance of DFPS 4183-14, to document the issue. The problem with the test procedure, in this case, was that per DFPS 4183-14 the 2/3-2223-89-C1 alarm was expected to annunciate when the detector was sprayed with test gas. As mentioned above, the 2/3-2223-89-C1 alarm is not designed to annunciate when sprayed with test gas but only when the detector loses power. This was not recognized by the licensee at the time even though the 2/3-2223-89-C1 alarm had not annunciated during the performance of DFPS 4183-14 since the first performance of the surveillance test in 2006. (See paragraph 4OA2.3 for more detail.) The licensee generated WO 1191692-01, Problems Encountered During Performance of DFPS 4183-14, to troubleshoot the failure of 2/3-2223-89-C1 to alarm when sprayed with test gas. The result of this work order was that all three smoke detectors needed to be replaced. This was documented in IR 957560, Three Smoke Detectors Require Replacement. Issue Report 957560 stated that the scope of work requested was to touch jumper between terminal 9 and 10 of each detector to determine if annunciator 2/3-2223-89-C1 alarmed. The author of the IR stated that annunciator 2/3-2223-89-C1 alarmed for each smoke detector and, therefore, the detectors were bad and needed to be replaced. In this case, the troubleshooting procedure did not identify that the cause of the failure of the 2/3-2223-89-C1 alarm to annunciate was a design issue and not an equipment issue. This was not recognized by the licensee at the time. However, surveillance test DFPS 4183-14 was performed again, per WO 1191661-01, D2/3 Annual PM Control Room HVAC System Smoke Detector Test, on February 3, 2010, this time with no issues regarding annunciator 2/3-2223-89-C1. The inspectors questioned how this could happen since the detectors, identified as bad in IR 957560 had yet not been replaced and no work had been performed on any of the smoke detectors in question. The system manager explained that steps within DFPS 4183-14 did not require the verification that annunciator 2/3-2223-89-C1 ever extinguished. Therefore, if the annunciator was in alarm at the beginning of the surveillance test, for whatever reason, then the test would have passed without issue. This issue would make DFPS 4183-14 inadequate because the surveillance could have passed without proper equipment operation. The inspectors searched and reviewed operator logs and corrective action program documents to determine if annunciator 2/3-2223-89-C1 was in alarm at the time the surveillance test was performed on February 3, 2010, and found no log entries or issue reports that would indicate that annunciator 2/3-2223-89-C1 was in alarm. The inspectors re-reviewed WO 1191661-01 and identified that there were separate steps to verify the annunciators on the 923-5 panel in the control room and the 2/3-2223-89 panel in the U2 switchgear room were reset after each individual smoke detector was tested. If the 2/3-2223-89 panel C1 alarm was in at the beginning of the test and would not extinguish, this should have been noted in the WO and/or in an IR. The inspectors concluded that this was not a valid explanation. The licensee performed fact finding based on the inspectors questions why this surveillance test passed when it should not have. The inspectors discussed the fact finding results with the licensee manager that performed the fact finding on April 6, 2011. The licensee found no explanation why the test passed. The individual that performed the test stated that the performance of that specific test could not be recalled. The satisfactory performance of DFPS 4183-14 on February 3, 2010, was unexplained. The unexplained satisfactory performance of a surveillance test procedure, that was later demonstrated to be not capable of being performed as written, was an Unresolved Item pending inspector review of additional licensee evaluation. (URI 05000237/2011002-01; 05000249/2011002-01) The inspectors reviewed WO 1264824-04, Three Smoke Detectors Require Replacement, performed on June 11, 2010, in which the smoke detectors were replaced and were to be post-maintenance tested. Smoke detector 2/3-8941-013, located on the Main Control Room HVAC outside air supply duct, was replaced but was not tested. The function of detector 2/3-8941-013 was to prevent or reposition ventilation dampers such that if smoke was detected coming into the building from outside, the smoke purge function of the control room ventilation system would be prevented. The WO stated that the dampers would not reposition to the smoke purge position, therefore, smoke detector 2/3-8941-013 could not be tested. This also meant that the control room ventilation smoke purge capability was non-functional. The smoke purge capability was still non-functional at the end of the inspection period. Troubleshooting was ongoing as of April 12, 2011, and the extent of the problems with smoke purge was unknown so there was no scheduled repair date. The smoke detector alarming in the control room should also result in manually switching to the isolation mode to prevent further smoke from entering the control room. The isolation dampers were separate for the smoke purge dampers and were functional. The inspectors determined the smoke purge control capability of detector 2/3-8941-013 could not be tested but the alarm function could have been tested and was not. |
| Site: | Dresden  |
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| Report | IR 05000237/2011002 Section 1R04 |
| Date counted | Mar 31, 2011 (2011Q1) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.04 |
| Inspectors (proximate) | J Beavers J Cameron M Jones N Valos R Langstaff T Briley T Go Z Falevits A Dunlop C Phillips D Melendez Colon E Sanchez Santiagoc Zoiad Melendez-Colon C Phillips D Reeser R Baker M Ring T Go J Draper |
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Finding - Dresden - IR 05000237/2011002 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Dresden) @ 2011Q1
Self-Identified List (Dresden)
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