05000305/FIN-2009002-04
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Finding | |
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| Title | Multiple Component Cooling Water Pipes in Close Proximity to High Energy Feedwater Lines |
| Description | The inspectors identified a unresolved item relating to the identification of multiple CCW pipes in close proximity to a high energy feedwater line. During a CCW system alignment walkdown, the inspectors identified a location where the steam supply pipe to the turbine-driven AFW pump and multiple CCW pipes, including the CCW line to the surge tank, were routed in close proximity to a16 inch feedwater line. The inspectors noted that the USAR, under Chapter 10A,Postulated Pipe Failure Analysis, stated where high-energy pipes were routed in the vicinity of structures and systems necessary for safe shutdown of the nuclear plant, a small break in the piping system would be postulated. However, the licensee informed the inspectors that the HELB basis was being updated and that there would no longer be a need to postulate cracks in that area of feedwater piping, based on vendor calculations that had been performed. The licensee provided the inspectors a 2005 extent-of-condition documentation sheet that described the concern of the CCW lines being in close proximately to the feedwater line. The document also restated, that under vendor calculation KNPP-205614-P01, Kewaunee would no longer be required to postulate a break or a crack in that area of piping. The inspectors reviewed the licensing basis for HELB and found that Kewaunee did not fall under the requirements of the NRCs Standard Review Plan, which allowed for analyzing potential stresses in high energy pipes that if found low enough would preclude the licensee from postulating cracks near safe shutdown equipment. The licensee did fall under the requirements of a letter sent to the licensee in 1972 by the Atomic Energy Commission, (the Giambusso letter signed by NRC staff member, Mr. A. Giambusso). The letter stated that where high-energy pipes were routed in the vicinity of structures and systems necessary for safe shutdown of the nuclear plant, a crack in the piping system would be postulated. The licensee performed an evaluation for the steam supply to the turbine-driven AFW pump and the CCW lines and found that they would not be affected by a feedwater pipe crack. The licensee, after further reviewing its HELB basis, stated that the CCW system may not be required for safe shutdown during a HELB. The inspectors reviewed the licensees list of systems required after a feedwater break and found that CCW was not listed as a required system. The inspector subsequently reviewed the licensees Appendix R Design Description for Safe Shutdown and found that CCW was listed as a required system for safe shutdown to hot shutdown. Specifically, CCW was required to perform reactivity and inventory control functions to support hot shutdown operations. The inspectors concluded that these functions were necessary for hot shutdown regardless of the initiating event. Therefore the inspectors could not validate the licensees assertion that CCW may not be required to support HELB. The licensee is currently updating its HELB basis and this item will remain unresolved until the licensee completes this effort and can determine whether CCW should have been included in the systems required for safe shutdown after a HELB(URI 05000305/2009002-04) |
| Site: | Kewaunee  |
|---|---|
| Report | IR 05000305/2009002 Section 1R15 |
| Date counted | Mar 31, 2009 (2009Q1) |
| Type: | URI: |
| cornerstone | Initiating Events |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.15 |
| Inspectors (proximate) | R Winter J Jandovitz J Cassidy M Kunowski R Krsek K Barclay P Cardona-Moralesj Cassidym Kunowski S Burton K Barclay D Lawver |
| INPO aspect | |
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Finding - Kewaunee - IR 05000305/2009002 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Kewaunee) @ 2009Q1
Self-Identified List (Kewaunee)
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