ML20072N070
| ML20072N070 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 08/24/1994 |
| From: | Helwig D PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9409020310 | |
| Download: ML20072N070 (3) | |
Text
a David R. Helwig
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%ce Prestaent Lirnerick Genereng staan
~h=y PECO ENERGY
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PECO Energy Corryony LNock Genereng Sunuq PO Bos P300 Sanatoga. PA e4644020 6t0 3271700, Ext 3000 i
August 24, 1994 Docket Nos. 50-352 50-353 License Nos. NPF--3 9 NPF-85 U.S.
Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC' 20555
SUBJECT:
Limerick Generating Station, Units 1 and 2 Response to Request for Additional Information NRC Combined Inspection Report Nos. 50-352/94-15 and 50-353/94-15 Attached is PECO Energy Company's response to a request for additional information for Limerick Generating Station, Units 1 and 2, which was contained in your letter dated July 26, 1994.
Your letter discusses a situation where it appeared that there was a mismatch between procedural requirements and actions taken which was not properly resolved.
Your letter indicated that this situation appeared to be similar to a previous event which was documented in NRC Combined Inspection Report 50-352/94-02 and 50-353/94-02, and resulted in a cited violation.
As a result, your letter requested a 30 day response detailing any additional corrective actions taken to prevent recurrence based on this more recent situation.
The attachment to this letter provides PECO Energy's recponse.
If you have any questions or require additional information, please contact us.
Very truly yours, 3 -
Attachment cc:
T.
T. Martin, Administrator, Region I, USNRC w/ attachment N.
S. Perry, USNRC Senior Resident Inspector, LGS 9409020310 940824 PDR ADDCK 050003S2 o
PDR 0
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Docket Nos. 50-352 and 50-353 Attachment August 24, 1994 Page 1 of 2 Response to Request for Additional Information Summary Description of Event No. 1 (NRC Violation 50-352/94-02-03)
The details of the event description, root causes and corrective actions for this event were provided to the NRC by PECO Energy's Reply to the Notice of Violation dated May 9, 1994.
This event involved a loss of shutdown cooling event which occurred i
as a result of personnel error.
An Instrumentation and Controls j
(I&C) technician performing a
surveillance test procedure incorrectly implemented a procedure step.
The incorrect action resulted in an unexpected response from the equipment being manipulated.
No adverse consequences resulted from the event as the logic associated with the equipment had been previously disabled.
The technician recognized a mismatch between the expected response and the actual response and discussed the condition with a supervisor.
Technical guidance was given to allow manipulation of the equipment to resolve the apparent discrepancy.
The technician proceeded to manipulate the equipment and continued on with the test.
Several steps later, a similar sequence of events occurred resulting in an isolation of HV-051-lF015B which caused a loss of shutdown cooling. Again the technician recognized a mismatch between expected and actual response.
Administrative procedure A-3,
" Temporary Changes to Approved Procedures and Partial Procedure Use," provides clear direction as to required actions to take when a mismatch such as this occurs.
In this case, procedure A-3 was incompletely implemented in that the surveillance test procedure was not changed to correct the mismatch in the response received prior to proceeding with the j
test.
As such, PECO Energy acknowledged non-compliance with procedure A-3 in our May 9, 1994 Reply to the Notice of Violation.
This event was discussed with all I&C personnel to reinforce the expectations concerning procedure A-3.
Summary Description of Event No. 2 (Inspection 50-352(353)/94-15i The details of the event description, root causes and corrective actions for this event were provided to the NRC by Licensee Event Report (LER) 2-94-006 for Limerick Generating Station, Unit 2,
dated May 9, 1994.
This event involved failure to stroke the 2B inboard and outboard main steam isolation valves (MSIVs) for surveillance required in accordance with Technical Specifications Section 4.0.5.
This event
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Docket Nos. 50-352 and 50-353 Attachment August 24, 1994 Page 2 of 2 occurred as a result of inadequate implementation of procedural requirements recently added to an existing I&C procedure.
The procedure revision was intended to incorporate testing requirements contained in other procedures to eliminate redundant stroking of the MSIVs.
However, the procedure which was revised specifically allowed technicians to not stroke the aforementioned valves due to the control logic being in an abnormal condition.
Although the procedure purpose and acceptance criteria specified that the valves must be stroked to satisfy Inservice Testing (IST) requirements, the technicians performing the test believed that they had performed the test satisfactorily since the test allowed them to skip steps which stroked the valves.
Although some ambiguity may have existed, the technicians perceived no mismatch in conditions, and therefore, did not implement any of the courses of action specified in procedure A-3.
The technicians' actions were not inconsistent with their understanding of the procedural requirements. The primary cause of this event was identified to be inadequate understanding of the procedural requirements due to unclear procedural guidance.
Corrective actions as a
result of this event focused on clarification of the procedural guidance.
Conclusion After reviewing all circumstances related to these two events, we have concluded that there is no clear link between them.
The first event involved a recognized mismatch in conditions which clearly should have prompted action in accordance with procedure A-3.
The second event resulted from inadequate procedural guidance which allowed technicians to misinterpret the intent of a procedural signoff step.
This is supported by the fact that several I&C technicians made the same error when performing similar surveillance tests.
L Regardless, additional discussion of the event has been conducted with I&C technicians to reinforce the expectation to involve supervision to determine appropriate course of action when procedure ambiguity exists.
We have determined that this additional action, in conjunction with the corrective actions identified previously in PECO Energy's May 9, 1994 Reply to Notice of Violation and LER 2-94-006 are sufficient to preclude recurrence of either of ther^ events.
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