ML102800553
| ML102800553 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 12/30/2005 |
| From: | Thomas Farnholtz NRC/RGN-IV/DRP/RPB-A |
| To: | NRC Region 4 |
| References | |
| FOIA/PA-2010-0245, RIV-2005-A-0115, RIV-2005-A-0130 | |
| Download: ML102800553 (7) | |
Text
[R*ALlEGE e toCGS sRIV-20Fl-A-0115 and RIV-2005-A-0130 .Page From: Thomas Farnholtz To: R4ALLEGE Date: Fri, Dec 30, .2005 11:27 AM
Subject:
CGS Allegations RIV-2005-A-015 15:and RIV-2005-A-0130 Place: R4ALLEGE Attached are the allegation review memos for the subject allegations. The licensee responded to both these allegation in the same response. But for clarity, I separated each allegation.
Tom Farnholtz Senior Project Engineer, Branch A Division of Reactor Projects Region IV (817) 860-8243 CC: Johnson, Claude
ALeLEGA29 6cEI0,2Z0A5 Membrandum To: ALLEGA) iJN FILE RIV-2005-A-O1 15 From: Thomas R. Farnholtz, Acting Chief Project Branch A Division Reactor Projects
SUBJECT:
CLOSURE OF ASSIGNED CONCERNS FOR ALLEGATION RIV-2005-A-01 15 This memorandum provides the background closure information for Allegation RIV-2005-A-01 15. On December 20, 2005, Energy Northwest responded to eight concerns identified in the allegation. In reviewing Energy Northwest's response, the NRC considered whether: (1) the licensee's response adequately addressed the individual concerns; and (2) the allegers concerns were substantiated.
Inspector Followup to Allegation RIV-200o-A-0115
Background:
On June 14, 2005, the Columbia Generating Station Service Water Pump A failed due to Intergranular Stress Corrosion Cracking (IGSCC) of the vertical pump shafts at the couplings. The pump was repaired and declared operable. Concerns were raised about the condition of the B service water pump because of its similar design and operating conditions. The B pump was not disassembled to be inspected or repaired due to parts issues and the plant was started up and operated with questions surrounding the ability of this pump to perform its safety function for its mission time. The plant startup following the failure of the A service water pump and the delay in establishing the actual condition of the B service water pump resulted in the concerns listed below.
The licensee's response to the following allegation concerns are based upon investigation conducted by the Nuclear Safety Issues Program (NSIP) Manager who is independent of the Plant Operations organization. In addition, the licensee performed four independent analysis of the issues of concern in the NRC allegations.
These included:
- 1. An evaluation of a concern in the Nuclear Safety Issues Program,
- 2. An assessment by the Columbia Corporate Nuclear Safety Review Board (CNSRB),
- 3. A detailed evaluation of the root cause of the SW-P-1A failure, including proposed corrective actions, and
...- 4---An-operability-procedure-compliance-review-concerning-the-determination fo-SW-P-1 B- -----. - -
operability.
The inspector considered these activities to be sufficiently independent of the organizations in question.
With regards to enforcement actions to be taken by the NRC, an Unresolved Item (URI) was issued in inspection report 05000397/2005003 to capture the issue of the failure to adequately address industry operating experience regarding service water pumps. This issue was unresolved pending the inspection of the B pump. We expect to conclude our inspection activities and significance determination and document the results by the end of the first quarter, 2006.
Concern 1 -
Technical staff members have expressed concern over the number of continuing risks taken by management in operating the plant in the face of uncertainty regarding the ability of critical safety-related equipment to meet its safety function should an accident occur. The basis for this allegation is the uncertain status of Standby Service Water Pump SW-P-I B. This pump shares the same design and environmental operating conditions as the A service water pump which failed on June 14, 2005, due to Intergranular Stress Corrosion Cracking (IGSCC) in the coupling of the vertical pump shaft segments. The working level engineers and some supervisors felt that SW-P-1B should be inspected before restart, but management proceeded to restart the station in spite of the uncertain status of SW-P-lB.
Conclusion -
The inspector did not substantiate the concern primarily due 'to the lack of examples of the "number of continuing risks taken by management." The one example provided (Service Water Pump B) does legitimately raise concerns which are shared by the NRC.
The licensee conducted interviews with eight engineers, one supervisor, wle Maintenance Manager, the previous and current Engineering Manager, and the Root Cause Analyst to determine the number of individuals involved in this concern. To address the continued operability of SW-P-1B, the licensee determined that the ultimate decision was reached in accordance with, and by the persons charged with making these decisions in accordance with applicable processes and procedures and was considered valid by the independent reviewer. It was also considered appropriate based on another independent review by the Corporate Nuclear Review Board.
The inspector considered the licensee's actions and conclusions to be adequate to support their position.
Concern 2 -
It was confirmed in conversations with the pump vendor, and an independent vibration consultant that vibration data could not be used to predict failures like those observed in the pump shaft on SW-P-1A.
Technical staff could not provide a basis for confidence that SW-P-1B could fulfill its safety function, even though it was currently meeting its Tech Spec surveillance requirements.
Conclusion -
The inspector substantiated the first part of this concern. Vibration data alone could not have been used to.predict this type of failure.--The-inspectordidnot substantiate the second Dart of this concern because no convincing evidence that the pump was inoperable was provided.
The licensee concluded that vibration data alone could not be used to predict margin to failure but continued vibration monitoring to ensure the ability to continuously assess any pump performance degradation. The licensee's response to this concern stated that the basis for confidence in the ability of SW-P-1B to continue to perform its safety function had multiple aspects. Technical Specification and In-Service Testing requirements was one element. Further, the pump was operable prior to the Service Water Pump A failure and continued to operate normally. Also, additional measures were put in place to closely monitor the pump each time it was required to start and run. The final operbility determination is made by the Shift Manager. Five different Shift Mangers over time made consistent determinations that the B pump remained operable. The licensee stated that applicable operability procedures had been followed.
The inspector concurred with this position since no information to the contrary is known.
Concern A Decision Team was convened to prepare a Decision Resolution regarding actions to be taken for SW-P-1B. The original recommendation was to postpone plant startup until the pump could be inspected and repaired if required. The original Decision Resolution was revised without concurrence of the team so that it supported startup and operation until parts became available.
Conclusion -
The inspector did substantiate the concern. The licensee determined that an error had been made when the Decision Resolution form was revised to support the decision to startup the plant but the names of the team members that did not support this decision were not removed, making it appear that these individuals supported the decision.
The licensee's response included a discussion of the operational decision making process as described in Administrative Procedure 1.3.67, "Effective Operational Decision Making," Revision 1. This procedure
specifies that the ultimate respoi ,sibility concerning disposition does not ixst with the Decision Team. The Decision Maker is to review the options presented, determine which option to adopt, and present the options and recommendations to the Decision Approver. The licensee did identify and correct an error involving revision to the Decision Resolution form that was revised to reflect the ultimate decision to restart the plant.
The names of the Decision Team members which had not recommended plant restart did remain on the form when they should have been removed. This error was entered into the licensee's corrective action program as Condition Repori- 05-05971.
The inspector considered this action to be adequate to address this issue.
Concern 4 -
Management is clearly uncertain of theability of Service Water Pump B to survive even short runs, much less the long mission time required for long term cooling.
Conclusion -
The inspector did not substantiate this concern. Licensee management was engaged in this issue from the time of the failure of service water pump A. The licensee considered the B service water pump to be operable but did establish a specific monitoring plan for the pump each time it was required to be _run.
--Licensee-management understood-the-concerns-regarding service-water-pump-B and the-fact-that- these concerns would remain until the pump was inspected and refurbished or replaced. They considered the pump to be operable and the pump continued to operate normally and in compliance with all of its Technical Specification surveillance testing requirements. The pump was closely monitored each time it was required to be run. Management imposed additional restrictions on the margin allowed for In-Service Testing by removing five percent margin otherwise allowed.
The inspector considered the actions taken by management to be acceptable given the information available at the time.
Concern 5 -
Service Water Pump B has not been disassembled and inspected following the identification of the failure mechanism of the A pump due to parts-availability. Inspection generally requires destruction of the outer coupling sleeves. It appears that coupling sleeves have been available for some time. Yet it appears that inspection and repair will be delayed until December.
Conclusion -
The inspector substantiated this concern. New shaft couplings had been available since September 2005. Licensee management opted to obtain all the parts necessary to perform a complete refurbishment or replacement. This decision resulted in a-schedule change to mid-December 2005.
The licensee procured new shaft couplings and had them available by September 2005. However, without new shafts available, these couplings would only provide a contingency repair should the existing couplings fail allowing the shafts to separate. Another contingency plan was developed which involved a design change to create a modified coupling. Management did not consider either of these contingencies preferable to procuring all of the parts necessary to perform a complete refurbishment or replacement, including new shafts, impeller, and refurbished pump bowl. This decision resulted in the schedule change to mid-December 2005.
In reaching this decision, management wanted to ensure that the end rebuit would be a completely refurbished standby service water pump.
The inspector agreed that the complete refurbishment or replacement option was appropriate for the long term. However, the shorter term considerations were not handled effectively since the basis for this decision was not communicated to the staff effectively.
Concern 6 -
The inspection of Service Water Pump A had been deferred since Refueling Outage 10, and was planned for the latest outage (Refueling Outage 17) but was deferred again. This was the pump that failed three days after the completion of Refueling Outage 17.
Conclusion -
The inspector substantiated this concern. Maintenance was not performed on the A service water pump prior to its failure on June 14, 2005.
The licensee indicated that they are addressing this issue. The root cause analysis documents a finding that a dominant root cause for this event (A service water pump failure) was a failure of the preventive maintenance
-program. The maintenance prograr at the station was premised on a condition-based monitoring process.
The shift from a scheduled maintenance preventive maintenance program to a condition-based program
-...occurred-in-1-996.- Thereafterthe-focus-was on the-use-of-condition-monitoring-to-determine -component -.-
replacement and refurbishment. As a result, scheduled pump and motor replacements were cancelled. The licensee stated that the term "deferral" is in many respects a mischaracterization as the bases for pump refurbishment (condition monitoring) were applied consistent with the plant processes. Accordingly, the root cause and contributing causes for this event are actually premised on weaknesses in the condition monitoring program that resulted in not performing maintenance on the pumps. One of the principal corrective actions is to develop and implement preventive maintenance basis for critical components.
The inspector considered this response to be adequate.
Concern 7 -
At least one of the technical staff brought the issue of the uncertain status of the B service water pump to the Nuclear Safety-Issues Program to bring further attention to the issue and to satisfy those concerned. The outcome of that effort is unknown. Meanwhile, management has been busy trying to "clarify" their position.
Conclusion -
The inspector substantiated this concern because the Nuclear Safety Issues Program final report had not been issued at the time this allegation was received. Therefore, the outcome of this effort was still unknown at that time. Concerning management "clarifying" their position, the ,inspector considered this to be acceptable since this was an ongoing issue over time.
The licensee indicated that the final report of the Nuclear Safety Issues Program for this case was issued on September 15, 2005. One of the recommended actions was to review the results of the investigation with the individual who raised the issue, the engineers who had previously voiced concerns, and with all concerned parties. These specific actions were completed on October 18, 2005.
The ifspector considered this acuon to be adequate although the delay in performing this action resulted in the concerns of these individuals not being addressed in a timely manner.
Concern 8 -
There appears to be substantial evidence of Nuclear Safety culture deficiencies in management. The deferral of maintenance on safety-related equipment results in risks taken on to enable the station to meet short term goals. The perception is that management is gambling with station safety to meet goals associated with personal gains.
Conclusion -
The inspector did not substantiate this concern due to lack of convincing evidence of actual deficiencies in nuclear safety culture on the part of licensee management. However, there was an appearance of management deficiencies in nuclear safety culture. The deferral of maintenance (or lack of an adequate preventive maintenance program) for safety-related equipment has negatively affected equipment reliability. This has resulted in a perception that management is gambling with station safety to meet goals associated with personal gains.
In their response, the licensee indicated that the assertion of the nuclear safety culture deficiencies appears to be -premised-on-theissue-of-the-possible-deferral-of-maintenance-activities.-T-he-deferral question- stems-from the implementation of a condition-based monitoring maintenance process.- -The licensee stated that, to the exte-ntthe undrlying culture concern raises any question -ast-th-e processes involve-d-for -addre-sing -safet issues and the openness of those processes, there have been extensive activities including numerous Condition Reports issued on the service water pump operability issues, implementation of the procedurally controlled decision-making process, the use of the Nuclear Safety Issues Program, and the differing professional opinion mechanism established by procedure. The licensee contends that the reasoned consideration of all concerns in those contexts fundamentally is reflective of a sound and positive safety culture. In addition, the extensive open discussion of the pump issues outside the procedural process belies any indication of a lack of openness or willingness to explore and listen to all perspectives on an issue.
Regarding the perception that management is gambling with station safety to meet goals associated with personal gains, nothing in these allegations supports such a perception. There was no basis for concluding that the startup following R-17 was authorized by management in the knowledge that the operability of service water pump A was in question. Further, the decision to restart following replacement of service water pump A was rational and consistent with plant procedures.
The inspector did not share the licensee's confidence regarding management's demonstration of a-sound and positive safety culture in this case. Also, no convincing evidence was presented of extensive open' discussion of the pump issues or a willingness to explore and listen to all perspectives on this issue. In general, the issues surrounding service water pumps A and B were not handled and communicated effectively and, because of this, did give the perception of management deficiencies in nuclear safety culture. However, the inspector could not condemn management's overall actual (not perceived) safety culture at the Columbia Generating Station based on this issue.