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| Quarter | Site | Title | Description | |
|---|---|---|---|---|
| 05000237/FIN-2006010-04 | 2006Q3 | Dresden | Full Flow Testing of the Diesel Driven Flood Pump at Design Conditions | The inspectors reviewed the details of the pump test and the licensees conclusion as documented. The inspectors noted that the pump capacity at the maximum pump speed was measured at 298 gpm at a discharge head of 114 psig. This was only 80.5 percent of the expected capacity of 370 gpm based on the manufacturers pump curve. The inspectors were concerned that the lower than expected flowrate may be an indication of pump degradation. In addition, the licensee tested the pump at only one point and assumed that the pump curve would follow the same pump curve established by the manufacturer. The inspectors questioned the method of testing and the method used to extrapolate the flowrate to generate a pump curve. Also during this inspection, the inspectors questioned licensee personnel to determine if any actions had been taken to address the cause of the 19.5 percent degraded pump test results, and whether the licensee initiated any actions to ensure the pump would not degrade further over time. The inspectors learned that no actions had been taken. Licensee personnel stated that the test result did not necessarily indicate that the pump was degraded. The inspectors concluded that the lack of additional points tested on the pump curve did not ensure the pump would provide adequate flow at design conditions. The inspectors concluded that the licensees corrective actions of IR 246038 were not fully effective. Specifically, the lack of a robust testing methodology to ensure performance of the emergency flood pump to the manufacturers pump curve resulted in the licensees planning to send the pump to an offsite facility for adequate testing. This is an unresolved item pending NRC review of the licensees planned corrective action to perform full flow testing of the diesel driven pump at design conditions. (URI 05000237/2006010-04; 05000249/2006010-04) |
| 05000237/FIN-2006010-03 | 2006Q3 | Dresden | Adequacy of Ground/Well Waterborne Monitoring to Satisfy Radiological Effluent Technical Specification Surveillance Requirements | No findings of significance were identified. However, the inspectors questioned the basis for the licensees waterborne ground/well offsite sampling locations and corresponding compliance with the RETS surveillance requirement specified in Chapter 12.5 of the ODCM. Specifically, Table 12.5-1 of the RETS, Radiological Environmental Monitoring Program, requires that quarterly ground/well waterborne samples be collected and analyzed from three sources only if likely to be affected. Waterborne sources likely to be affected are defined in Table 12.5-1 as those that are tapped for drinking or irrigation purposes in areas where the hydraulic gradient or recharge properties are suitable for contamination. The licensee has historically sampled from two offsite wells located to the south and west of the Dresden site, both south of the Illinois River. Liquid radwaste effluents are discharged to the Illinois River which flows in a westerly direction. As determined during the licensees most recent land use census, several residential wells of varying depths located on the northern banks of the Illinois River downstream of the licensees liquid effluent (radwaste) discharge point are used as potable sources and/or for irrigation purposes and potentially may be affected sources if the hydraulic gradient or recharge properties are suitable. However, the technical basis for limiting the well water sampling program to the two wells historically sampled versus other offsite wells including residential wells downstream of the stations liquid effluent discharge into the Illinois River on the northern banks of the river could not be provided by the licensee. Consequently, compliance with Table 12.5-1 of the RETS could not be determined. As documented in issue report (IR) 532766, the licensee is contemplating plans to further evaluate Dresden site hydrologic data, including several existing hydrogeology studies, to validate its historical well sampling activities and to assess compliance with Table 12.5-1 of the RETS. Pending the outcome of the licensees evaluation and the NRCs review of that information, this issue is categorized as an Unresolved Item (URI 050-237/2006010-03; 050-249/2006010-03). |
| 05000237/FIN-2006010-05 | 2006Q3 | Dresden | DOA 1900-01, step D.1.c. Can Not Be Performed Under a Loss of AC Power Coincident with Loss of Coolant Accident (LOCA) Conditions | The inspectors identified an unresolved item regarding the performance of DOA 1900-01, Loss of Fuel Pool Cooling, Revision 14. DOA 1900-01, step D.1.c. can not be performed under a loss of AC power coincident with a loss of coolant accident (LOCA) conditions. On January 18, 2006, during testing of the 2A fuel pool cooling pump, per DOA 1900-01, heat exchanger tube side relief valves 2-1999-279 (A relief valve) and 2-1999-280 (B relief valve) lifted. On January 20, 2006, during testing of the 2B fuel pool cooling pump, per DOA 1900-01, both A and B heat exchanger tube side relief valves (2-1999-279 and 2-1999-280) lifted. The 2A fuel pool cooling pump was tested again on January 20, and both A and B relief valves lifted. Following each of the incidents, DOP 1900-01, Fuel Pool Cooling and Cleanup System Startup, was utilized to reseat the relief valves and return the system to a stable condition. The licensee concluded that after a fuel pool cooling pump trip, the pump can not be re-started without operator manual actions in the reactor building. On January 20, 2006, the licensee determined that DOA 1900-01, step D.1.c. can not be performed under a loss of AC power coincident with loss of coolant accident (LOCA) conditions. Step D.1.c. provides guidance on how to start a fuel pool cooling pump in case access to the reactor building is not possible. This condition affects Unit 2 and likely affects Unit 3. These events were documented in IR 444332. The inspectors challenged the licensee as to whether the condition of Unit 2 (and potentially Unit 3) fuel pool cooling system should be an operator workaround or challenge. The licensee initiated IR 528541 to address the inspectors concern. Also, the inspectors inquired as to whether any compensatory actions were in place and if there was an alternate success path to accomplish the re-start of the fuel pool cooling pumps under a loss of AC power coincident with loss of coolant accident (LOCA) conditions. The compensatory action in place directed operations personnel to take actions to ensure DOA 1900-01, step D.1.c. is not used on either unit until a solution to the problem is implemented. At the end of the inspection period, the licensee was still evaluating if there is an alternate success path to accomplish the re-start of the fuel pool cooling pumps. The inspectors considered this issue to be an unresolved item pending evaluation efforts. |