LIC-07-0062, NRC Inspection Report 05000285-06-018, Reply to a Notice of Violation (NOV) EA-07-047

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NRC Inspection Report 05000285-06-018, Reply to a Notice of Violation (NOV) EA-07-047
ML071860139
Person / Time
Site: Fort Calhoun Omaha Public Power District icon.png
Issue date: 06/28/2007
From: Reinhart J
Omaha Public Power District
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-07-047, LIC-07-0062 IR-06-018
Download: ML071860139 (5)


Text

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Omaha Public Power District 444 South 16th Street Mall Omaha NE 68102-2247 June 28, 2007 LIC-07-0062 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

References:

1.. Doc4 .50-285 .

2. Letter iroin NRC (A. Vegel) to OPPD (R. T. Ridenoure) dated March 2, 2007 (NRC-07-0020)
3. Letter from NRC (B. S. Mallett) to OPPD (R. T. Ridenoure) dated May 29, 2007 (NRC-07-064)

SUBJECT:

NRC Inspection Report 05000285/2006018, Reply to a Notice of Violation (NOV) EA-07-047 In Reference 3, the NRC transmitted a Notice of Violation (NOV) to the Omaha Public Power District (OPPD). The NOV resulted frommaintenance activities on Containment Spray Header Isolatido Valvee HCV-345 "that caused the valve t0.be. installed in the wrong orientation. In the attachment to this letter6iOPPD las proVideda' epjly~to~theNOV.

Based on the critenia provided ih7 the NRC Inspection Manual Chapter- 0609, "Significance Determination 'Procels',".-Attachffi2ii 2,...rP-ocess.

.n for .Appealing NRC Characterization of Inspection Findings,"fit. appearsý that'PPD

- hs no basis for appeal;.of this NOV since the NRC has documented the basis for their conclusi*Qns. While communicafion and interaction between NRC and OPPD on this issue were generally very good, there was a -lapse in communication effectiveness at a critical point in the process.

The NRC provided the preliminary assessment of the safety significance. of this finding in Reference 2." The. preliminary. safety, sigT.ficance assessment. indicated an increase in core damage frequency (CDF) for internal events of 5.7E-6/year, or '"6White" for safety significance.

Following receipt of the preliminary assessment, OPPD requested a regulatory conference which was held on' Apnril16,6.2007. During preparations for the regulatory. conference, ýthere was significant open cormmunication between OPPD and the NRC. In Reference 2, theNRC clearly identified those areas where OPPD, and the* NRC agreed,, and those areas where there was disagreement. It waýsralso Clear in Reference 2 that in preparng,. for. the regulatory conference, OPPD shouldcdonfeentrate.effortSon those areas of disagreement.>, .. ... ..... < . ..

p4odsg Employment with Equal Opportunity.,.

At the regulatory conference, OPPD provided the probabilistic risk assessment (PRA) model for two dominant scenarios previously discussed with the NRC. The safety significance assessment conducted by OPPD determined the event to be 4.2E-7/year, or "Green" for safety significance.

In Reference 3 the NRC disagreed with OPPD and concluded the safety significance as 5.7E-6/year, or "White." Based on Reference 3, it appears that the NRC changed position on some of the initial areas of agreement with OPPD noted in Reference 2. Had OPPD known that the NRC disagreed with the position on those areas, information would have been presented at the regulatory conference to support OPPD's position.

OPPD is supportive of NRC's intent that the Reactor Oversight Process (ROP) should be predictable and repeatable. OPPD is considering working with the Nuclear Energy Institute (NEI) to improve the ROP such that similar situations can be avoided in the future.

This letter does not c094a*jiy regulatory commitments. If you should have any-questions, please contact me.

, e Director ort Calhoun Station JAR/dkg Attachment c: B. S. Mallet, NRC Regional Administrator, Region IV A. B. Wang, NRC Project Manager L. M. Willoughby, NRC Senior Resident Inspector Winston & Strawn

LIC-07-0062 Attachment Page 1 REPLY TO A NOTICE OF VIOLATION Omaha Public Power District Docket No. 50-285 Fort Calhoun Station License No. DPR-40 EA-07-047 During an NRC inspection completed on February 13, 2007, a violation of NRC requirements was identified. In accordance with the NRC Enforcement Policy, this violation is listed below:

10 CFR Part 50, Appendix B, Criterion V, "Instructions, Procedures, and Drawings," states, in part, that activities affecting quality shall be prescribed by documented in-- on, procedures, or drawings of a -type appropriate to the circumstances ai'd shall be accomplished in accordance with these instructions, procedures, or drawings.

Contrary to the above, in May 2005, Fort Calhoun Station personnel accomplished maintenance activities without procedures appropriate to the circumstances.

Specifically, the licensee performed maintenance and post-maintenance activities on Containment Spray Header Isolation Valve HCV-345 using procedures that were not appropriate to the circumstances because the procedures did not require actions to verify the correct orientation of the valve. As a result, the valve was installed in the wrong orientation during maintenance, and post-maintenance testing did not detect the improper reassembly prior to returning the valve to service. This failure caused one train of the Containment Spray system to be inoperable from May 11, 2005 to September 9, 2006.

This violation is associated with a White SDP finding.

OPPD Response

1. Reason for the Violation On three separate occasions during the 2005 refueling outage, the containment spray header isolation valve, HCV-345, was removed from the system, disassembled, reassembled, and returned to the system. The activities performed during and following the maintenance did not identify the valve internals had been reassembled incorrectly.

Due to the incorrect assembly, when the valve actuator and remote position indication indicated closed, the valve was open. The valve was approximately 80% closed. The valve is known to have been operating correctly prior to the 2005 outage. In November 1990, an air pressure test of the HCV-345 demonstrated that actual valve position matched indicated position. A review of the maintenance records concluded HCV-345 was not removed from the system between 1990 and 2005.

LIC-07-0062 Attachment Page 2 Technical Specifications requiite the containmnent spray pumps and associated valves to be operable. HCV-345 is associated with the containment spray pumps and is required to function during accident conditions. The design basis analysis assumes the spray valves will be fully open when necessary. A partially open spray valve would not allow the flow rate used in the design basis accident analysis. Therefore, HCV-345 was not capable of performing its specified function and was not operable.

A root cause analysis of these events was completed. As a result, Fort Calhoun Station (FCS) determined that the maintenance procedure allowed flexibility of performing selected portions of the procedure without providing adequate annotation of risk important steps that could impact the final valve alignment. In addition, reliance on the procedure used tý conduct the maintenance without detailed acceptance criteria or verifications to enistni-proper valve operation resulted in a failure of the post maintenance test process to identify the error in assembly of the valve.

2. Corrective Steps Taken and Results Achieved The safety related air operated ball and butterfly valves, that are not containment isolation valves, were identified. Any risk important steps that require annotation and second verification were identified. Post maintenance testing was verified to ensure appropriate criteria exists.

In addition, the procedure for the inspection and repair of these control valves has been revised to include the following:

1) Manufacturer's index marks were referenced and the directions to add additional match marks during disassembly were removed.
2) Specific acceptance criteria on verifying the valve open or closed as part of final reassembly and annotating these steps as post maintenance test steps was included.
3) The format of the procedure was changed to allow partial performance, such as packing replacement.
4) Risk important steps (such as verification of valve position, i.e., post maintenance test) were annotated-and the procedure included a second verifier for these steps.

In addition, enhancements were made to the training provided to individuals performing maintenance on HCV-345. The steamfitter mechanic training program master plan was revised to include just-in-time, training prior to outages where HCV-345 is going to be disassembled. FCS has also acquired a mock-up of the HCV-345 valve for use in training personnel.

LIC-07-0062 Attachment Page 3

3. Corrective Steps That Will Be Taken To Avoid Further Violations Corrective actions to prevent recurrence have been completed as noted above. Further enhancements may be implemented by the corrective action system.
4. The Date When Full Compliance Will Be Achieved Fort Calhoun Station is currently in full compliance.