ML20078M612
| ML20078M612 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 11/28/1994 |
| From: | Mueller J NEBRASKA PUBLIC POWER DISTRICT |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NLS940117, NUDOCS 9412020253 | |
| Download: ML20078M612 (3) | |
Text
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COOPER NUCLEAR STATION
~ Nebraska Public Power District
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g-NLS940117 November 28, 1994 U.S.
Nuclear Regulatory Commission Attention: Document Control Desk Washington D.C.
20555
Subject:
Reply to Notice of Violation NRC Inspection Report No. 50-298/94-24 Gentlemen:
The Nebraska Public Power District (District) hereby submits its response to the Notice of Violation (NOV) transmitted with NRC Inspection Report No. 50-298/94-24.
This inspection report documents the results of the NRC inspection conducted by Messrs.
R.
A.
- Kopriva, W.
C.
- Walker, T.
Reis, and R.
V.
Azua from July 31 through September 10, 1994, on activities authorized at Cooper Nuclear Station (CNS).
The NRC identified one violation during its inspection of CNS.
An explanation of the violation and corrective actions taken and planned in response to the violation is presented below.
Statement of Violation (50-298/9424-01) 10CFR50, Appendix B, Criteria V.
states, in part, that activities affecting quality shall be prescribed by documented instruction, procedures or drawings, of a type appropria te to the circumstances and shall be accomplished in accordance with the instructions.
Contrary to the above, on August 19, 1994, a loss of the no break power system occurred because prescribed instructions in System Operating Procedure 2.2.22, Revision 26, "Vi tal Instrument Power System, " were not spccifically followed, Admission or Denial of the Violation The District admits the violation.
I 91 '
9412O20253 941128 PDR ADOCK 05000298 O
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NLS940117 November 28, 1994 Page 2
,. Reason for the Violation The reason for the violation is inadequate labeling on the No Break Power Inverter Panel; I
On August 19, 1994, at 5 : 00 am, the power to the No Break Power Panel (NBPP) was lost while attempting to remove the NBPP inverter from service.
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In preparation for performing a test discharge of the 250 V 1A Station Battery,'
the NBPP inverter was transferred to its alternate source, MCC-R, per Section 8.11.2 of Station Operating Procedure (SOP) 2.2.22.
Following the discharge test and prior to performing an equalize charge, the NBPP inverter was to be removed from service per Section 8.13 of SOP 2.2.22.
During performance of that procedure power was lost to the NBPP. The procedure requires placing the MANUAL BYPASS SWITCH in the ALTERNATE SOURCE TO LOAD position followed by opening the INVERTER OUTPUT breaker. The INVERTER OUTPUT breaker is located on the lef t side of the inverter and is labeled just that. There is also a breaker labeled SYSTEM OUTPUT located just next to the MANUAL BYPASS SWITCH.
A review of the Ronan alarm printouts suggests that the SYSTEM OUTPUT breaker was opened instead of the
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INVERTER OUTPUT Breaker.
The breaker designation on the front of the NBPP inverter is ambiguous, leading the operator to believe that the correct action l
was being taken.
Inadequate labeling on the Static Inverter and the Static Switch misled the operator to open the wrong breaker.
l Also, two placards, which have startup and shutdown procedure steps are mounted on the Static Inverter, not on the Static Switch.
The breaker labeled SYSTEM OUTPUT is on the Static Switch and the Inverter Output breaker is labelad INVERTER OUTPUT.
The sixth step on the shutdown placard states, "For complete shutdown open SYSTEM OUTPUT breaker." Therefore, this step of the placard also misled the operator which contributed to the loss of power to the NBPP.
In addition, the Alternate Source AC Input to Static Switch Breaker and the System Output Breaker indicating lenses are opposite of the standard plant convention (i.e.,
red / closed and green /open).
It also contributed toward misleading the operator.
1 Immediate Corrective Actions and Results Achieved The loss of power to the NBPP.was promptly recognized by the Control Room operators and Abnormal Procedure 2.4 6.7, "No Break Power Panel Failure," was entered.
Consequently, the NBPP was restored to service at approximately 5:20 am.
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e NLS940117
. November 28, 1994 l
Page.3
,The following immediate ' actions have already been taken to correct the existing j
conditions for full compliance:
l (1)
The Static Inverter A and the Static Switch have been. relabeled.
In addition, a human factors review has been completed with the appropriate mimics installed to aid operations personnel.
(2)
Two startup and shutdown placards have been removed from. the f ace of Static Inverter A.
(3)
Station Operating Procedure 2.2.22 nas been upgraded to enhance i
Section 8.13.
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Actions Taken to Prevent Recurrence The long-term ac. ions to preclude recurrence include the following:
e (1)
The indicating lens color scheme problem for System Output Breaker and the Alternate AC Input to Static Switch Breaker will be corrected through.an appropriate design change.
f (2)
A comprehensive labeling procedure is being developed to. aid in ensuring that equipment labels are appropriate for their application.
Date When Full Compliance will be Achieved l
Presently, CNS is in full compliance with 10CFR, Part 50, Appendix B, Criteria V.
The long-term actions such as the design change and the labeling procedure development will be tracked by the CNS Nuclear Action Item Tracking System (NAITS) to completion.
If there are any questions regarding the information presented on these matters, please contact me.
A/LB/))h47 John H. Mueller Site Manager l
/nr i
cc:
Regional Administrator USNRC - Region IV f
Arlington, Texas NRC Resident Inspector Cooper Nuclear Station
~NPG Distribution
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