The inspectors identified an unresolved item associated with a potentially inadequate procedure for
internal flooding events. Specifically, the licensees Abnormal Operating Procedures did not provide adequate instructions for operators to mitigate the effects of an internal flood from a pipe break (e.g., fire main) on plant equipment. On September 7, 2007, the inspectors commenced walkdowns of the auxiliary building to determine if vulnerabilities existed to
internal flooding events. The inspectors noted that the station had watertight doors at the entrances to the Safety Injection Pump Areas (Rooms 21 and 22) and Spent Regenerant Tank and Pump Area (Room 23). The inspectors questioned the operators whether there were instructions, procedures, etc. that would direct the closure of the watertight doors during a flooding event. The inspectors found that the only applicable procedure was ARP-AI-100/A50,
Annunciator Response Procedure A50 Local
Annunciator A50 Waste Disposal, Revision 10. The inspectors further questioned what procedures directed general actions during an
internal flooding event. While some abnormal operating procedures (
AOPs) had guidance for the event where a specific system might rupture, (e.g., raw water piping) there were no procedures for nonsafety related piping ruptures (e.g., fire water system). The inspectors concluded that if these systems, or other systems not already specifically addressed in the
AOPs, were to break there may not be sufficient direction to operators on how to respond (e.g., tripping the plant, securing water tight doors, protecting equipment, stopping the leak). The inspectors concluded additional information was needed associated with the station licensing and design bases with regard to internal and external flooding risks. The licensee initiated Condition Report 2007-0128 to assemble additional information and evaluate this issue. The inspectors determined that additional information was required to determine the acceptability of the licensees treatment of
internal flooding events. Additional information was needed to determine whether a violation of regulatory requirements occurred. Pending further review of additional information provided by the licensee, this issue is being treated as an unresolved item:
URI 05000285/2007005-02, Potential Inadequate
Internal Flooding Procedure.
