05000237/FIN-2009005-07
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Finding | |
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Title | Changes to EAL HU6 Potentially Decreased the Effectiveness of the Plans without Prior NRC Approval |
Description | The inspectors reviewed changes implemented to the Dresden Station Radiological Emergency Plan Annex EALs and EAL Basis. In Revision 24, the licensee changed the basis of EAL HU6, Fire not extinguished within 15 minutes of detection within the protected area boundary, by adding two statements. The two changes added to the EAL basis stated that if the alarm could not be verified by redundant control room or nearby fire panel indications, notification from the field that a fire exists starts the 15-minute classification and fire extinguishment clocks. The second change stated the 15-minute period to extinguish the fire does not start until either the fire alarm is verified to be valid by additional control room or nearby fire panel instrumentation, or upon notification of a fire from the field. These statements conflict with the previous Dresden Station Annex, Revision 23, basis statements and potentially decrease the effectiveness of the Plans. Dresden Station Radiological Emergency Plan Annex, Revision 23, EAL HU6, initiating condition stated, Fire not extinguished within 15 minutes of detection, or explosion, within the protected area boundary. The threshold values for HU6 were, in part: 1) Fire in any Table H2 area not extinguished within 15 minutes of Control Room notification or verification of a Control Room alarm, or 2) Fire outside any Table H2 area with the potential to damage safety systems in any Table H2 area not extinguished within 15 minutes of Control Room notification or verification of a Control Room alarm. Table H2, Vital Areas, were identified as reactor building, auxiliary electric room, control room, diesel generator rooms, 4 kilovolt emergency core cooling system switchgear area, battery rooms, control rod drive and component cooling service water pump rooms, turbine building cable tunnel, turbine building safe shutdown areas, and crib house. The basis defined fire as combustion characterized by heat and light. Sources of smoke such as slipping drive belts or overheated electrical equipment do not constitute fires. Observation of flame is preferred but is not required if large quantities of smoke and heat are observed. The basis for Revision 23, EAL HU6 thresholds 1 and 2 stated, in part, the purpose of this threshold is to address the magnitude and extent of fires that may be potentially significant precursors to damage to safety systems. As used here, notification is visual observation and report by plant personnel or sensor alarm indication. The 15-minute period begins with a credible notification that a fire is occurring or indication of a valid fire detection system alarm. A verified alarm is assumed to be an indication of a fire unless personnel dispatched to the scene disprove the alarm within the 15-minute period. The report, however, shall not be required to verify the alarm. The intent of the 15-minute period is to size the fire and discriminate against small fires that are readily extinguished (e.g., smoldering waste paper basket, etc.). Revision 24 of the Dresden Station Radiological Emergency Plan Annex, changed the threshold basis for EAL HU6 by adding the following two statements: 1) If the alarm cannot be verified by redundant control room or nearby fire panel indications, notification from the field that a fire exists starts the 15-minute classification and fire extinguishment clocks, and 2) The 15-minute period to extinguish the fire does not start until either the fire alarm is verified to be valid by utilization of additional control room or nearby fire panel instrumentation, or upon notification of a fire from the field. The two statements added to the basis in Revision 24 conflict with the Revision 23 threshold basis and initiating condition. The changed threshold basis in Revision 24 could add an indeterminate amount of time to declaring an actual emergency until a person responded to the area of the fire and made a notification to the control room of a fire in the event that redundant control room or nearby fire panel indications were not available. Pending further review and verification by the NRC to determine if the changes to EAL HU6 threshold basis potentially decreased the effectiveness of the Plans, this issue was considered an Unresolved Item. (URI 05000237/2009005-07 |
Site: | Dresden ![]() |
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Report | IR 05000237/2009005 Section 1EP4 |
Date counted | Dec 31, 2009 (2009Q4) |
Type: | URI: |
cornerstone | Emergency Prep |
Identified by: | NRC identified |
Inspection Procedure: | IP 71114.04 |
Inspectors (proximate) | R Jickling C Moore C Phillips D Melendez Colon D Sand F Ramirez J Benjamin J Draper J Mcghee L Kozak M Holmberg M Mitchell M Ringr Jicklingh Peterson |
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Finding - Dresden - IR 05000237/2009005 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Dresden) @ 2009Q4
Self-Identified List (Dresden)
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