05000443/LER-2003-001
| Seabrook Station | |
| Event date: | 06-10-2003 |
|---|---|
| Report date: | 11-13-2003 |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 4432003001R01 - NRC Website | |
I. Description of Event
At approximately 0500 hours0.00579 days <br />0.139 hours <br />8.267196e-4 weeks <br />1.9025e-4 months <br /> on June 10, 2003, with the plant operating in MODE 1 at 100% power, the "A" Emergency Diesel Generator (EDG) -1A [EK] was declared inoperable in order to perform preventive maintenance. During the preventive maintenance, broken Belleville washers were discovered on cylinder head #3 [ENG]. Due to a potential for a common mode failure, EDG-1B [EK] was started and run unloaded at 1701 on June 10, 2003 to meet the requirements of Technical Specification (TS) 3.8.1.1, action b.
A subsequent management review on June 18, 2003 (discovery date) determined that the unloaded testing of EDG-1B did not adequately address the footnote ("1 for Surveillance Requirement (SR) 4.8.1.1.2a.5 and therefore did not meet the requirements of TS 3.8.1.1, action b. As a result of not completing surveillance requirement 4.8.1.1.2a.5, TS 4.0.3 was entered at 1700 on June 18, 2003.
The first sentence of the footnote (***) for SR 4.8.1.1.2a.5 was added to License Amendment request (LAR) 01-01 as a result of a comment received during the Nuclear Safety Audit Review Committee's (NSARC) review of the LAR. The intention of adding the sentence to the footnote was to provide additional clarification to plant operators when performing the monthly surveillance testing of the EDG units. However, the addition of the first sentence unintentionally linked the requirement to perform a loaded test of the operable EDG unit in accordance with SR 4.8.1.1.2a.6 to TS 3.8.1.1, actions b and c. Incorporation of the reviewer's comment resulted in an unintended material change to the footnote. This change in intent was not recognized by other licensee personnel and the NSARC and did not receive an additional interdisciplinary review and SORC review prior to submittal to the NRC.
In response to a February 14, 2002 question regarding SR 4.8.1.1.2a.5, Regulatory Compliance concluded that a loaded test of the diesel was not required when TS 3.8.1.1, action b or c are entered. Multiple opportunities to address the incorrect conclusion were missed prior to the event that resulted in the non-compliance with the TS action statement requirements.
Failure to complete surveillance requirements 4.8.1.1.2a.5 and 6 within the required action time defined by TS 3.8.1.1, action b, constitutes a noncompliance with the requirements of TS 3.8.1.1. EDG-1B was subsequently satisfactorily retested under loaded conditions June 19, 2003 at 0325. The duration of the noncompliance from the time of discovery (1700, June 18, 2003) until TS 3.8.1.1 action b was satisfied (0325, June 19) was 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />, 25 minutes. This event represents a condition prohibited by the Technical Specifications and is reportable pursuant to 10 CFR 50.73(a)(2)(i)(B).
II. Cause of Event
The cause of this event was a failure by Licensee personnel (licensed and non-licensed) to understand the entire affect of a change to the wording proposed in SR 4.8.1.1.2a.5, footnote ("1, originally proposed in LAR 01-01. This error was not detected due to an inadequate LAR review process that allowed a comment to be incorporated during the (NSARC) review process. The LAR review process had insufficient barriers, and did not require a complete interdisciplinary review of the LAR with the revised wording incorporated. The LAR was primarily initiated to support corrective actions associated with the December 2000 failure of an EDG. The changes to the footnote were a very small part of a larger change to Technical Specifications.
Seabrook Station 0500-0443 An additional contributing cause (management deficiency) of this event was an inadequate evaluation and response to questions on TS 3.8.1.1 by Regulatory Compliance Department personnel. There were three occasions where questions were asked regarding the need to load the engine. In each instance, the Regulatory Compliance Department personnel relied upon the initial evaluation that stated the (*") only applied to the monthly surveillance.
Analysis of Event
There were no adverse safety consequences as a result of this event. Subsequent testing of EDG-1B on June 19, 2003 indicated that a common mode failure did not exist. EDG-1B remained operable and was capable of performing its intended safety function. This event is significant because plant operators did not correctly perform the actions required by TS 3.8.1.1, action b to run EDG-1B in a loaded condition.
As described in Seabrook Station — NRC Integrated Inspection Report 05000443/200303 issued on July 29, 2003, the finding associated with this event was determined to be of very low safety significance.
IV. Corrective Actions
Root Cause
An additional interdisciplinary review will be added to the LAR review process to address material changes that are made to the wording of a Technical Specification during the SORC, CNRB, and NRC review.
Contributing Causes
- Regulatory Compliance Department personnel have been briefed on the event and the lessons learned.
- Operations Department shift crews will be briefed by Regulatory Compliance supervision to address the lessons learned from this event.
Extent of Condition
- A review of license submittals since LAR 01-01, has been performed to ensure that review comments did not materially change the intent of the Technical Specifications.
V. Additional Information
None VI. Similar Events where one EDG unit was declared inoperable due to kVAR fluctuations. As a result of this event, plant operators failed to start the operable EDG unit as required by TS 3.8.1.1, action b within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after discovery. The cause of the event was the lack of formal training given to plant operators regarding the requirements of TS 3.8.1.1, action b.