ML20052G505
| ML20052G505 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 05/04/1982 |
| From: | Papay L SOUTHERN CALIFORNIA EDISON CO. |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| Shared Package | |
| ML20052G495 | List: |
| References | |
| NUDOCS 8205180417 | |
| Download: ML20052G505 (3) | |
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P. O. BOX 800 2244 WALNUT GROVE AVENUE
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ROSEMEAD, CALIFORNIA 91770
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May 4, 1982 U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596-5368 Attention:
Mr. R. H. Engelken, Regional Administrator Docket No. 50-206 IE Inspection Report 50-206/82-10 San Gnofre - Unit 1
Dear Mr. Engelken:
Your letter of April 9,1982 forwarded IE Inspection Report No.
50-206/82-10 and a Notice of Deviation resulting from the March 1-31, 1982 routine monthly inspection by L. F. Miller.
Enclosure (I) of this letter provides our response to the Notice of Deviation contained in Appendix A of the subject report.
I trust the enclosure responds adaquately to all aspects of the Deviation.
I understand that notarization of the response is not required in the case of a Deviation.
If you have any questions or if we can provide additional information, please let me know.
Sincerely, Enclosure I cc:
L. F. Miller (NRC Site Inspector - San Onofre Unit 1) i 82 0 518 0 W 7
ENCLOSURE _I Response to the Item of Deviation identified in Appendix A to IE Inspection Report 50-206/82-10.
ITEM "The Final Safety Analysis, Paragraph 2.6.2.3, states, 'Each of the two flushable, mixed-bed demineralizers are designed to maintain reactor coolant purity through one core cycle with one percent defective fuel rods... Local pressure gauges are provided to measure pressure drop, which is designed to be a maximum of 35 psi, across the demineralizers.'
Contrary to this design maximum differential pressure value, the inspector observed the north mixed-bed demineralizer in operation on February 10, 1982, with a 46-47 psi differential pressure across the demineralizer as measured by local pressure gauges PI 1107A and 1107B.
Furthermore, the inspector determined through interviews of licensed operators on February 12, 1982, that operation with differential pressures as high as 80 psi has been customary for several years.
This is a deviation."
RESPONSE
1.
CORRECTIVE STEPS WHICH HAVE BEEN TAKEN AND RESULTS ACHIEVED The following actions have been taken in response to the identified deviation:
a.
Immediately upon notification of the existing deviation, the Unit 1 Superintendent directed that the demineralizer differential pressure be restored to within the specification stated in the Final Safety Analysis Report (FSAR).
This action was accomplished on February 10, 1982. Additionally, the Unit 1 Superintendent counseled all Watch Engineers on the necessity and importance of operating plant systems in accordance with design limits as specified by the FSAR, Technical Specifications, and Operating Instructions.
b.
On February 25, 1982, Station Engineering issued a memorandum l
specifying further guidelines to be used in the operation of I
the Mixed-Bed Demineralizer System.
This memorandum emphasizes l
the provisions of Operating Instruction S01-4-11, " Letdown Demineralizer System", and outlines specific actions which should be taken in the event the demineralizer differential pressure exceeds thirty-five pounds per square inch, gage.
c.
An engineering evaluation issued March 24, 1982 examined the potential consequences of demineralizer operation at excessive differential pressure.
The analysis shows that even in the event of failure of the internal resin retention screen, plant operation is maintained without endangering the health and safety of the public.
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4 2.
CORRECTIVE STEPS WHICH WILL BE TAKEN TO AY0ID FURTHER DEVIATIONS 6F THIS TYPE Tdo long-term measures have been initiated to ensure the proper operation of the Letdown Domineralizer System:
a.
This event and its ramifications on plant operations will be addressed in future operator requalification training.
b.
On March 3,1982, Station Engineering issued a three-part action plan to address the Mixed-Bed Demineralizers:
i (1 ) To determine if decreasing letdown flow is 1 viable method a
for maintaining demineralizer parameters within design limits, letdown flow has been reduced to approximately 4
forty-five gallons per minute until the necessary data has been obtained.
(2)
Special Procedure 501-SPE-530, " Mixed-Bed Demineralizer l
Differential Pressure Test", has been prepared to l
determine if resin retention screen blockage or damage has resulted from previous operation.
This test will be performed in approximately six to nine months, when the next Mixed-Bed Demineralizer is in need of resin replacement.
(3) Data obtained from the results of actions (1) and (2) above will be incorporated as necessary into existing operating procedures.
The necessity for demineralizer repair and/or design modification will be evaluated.
Letdown flow will be maintained within the guidelines of the Station Engineering memorandum of February 25, 1982 pending the outcome of the evaluation.
3.
DATE WHEN FULL CONFORMANCE WITH THE CITED FSAR COMMITMENTS WILL l
BE ACHIEVED t
Full conformance with the FSAR was achieved on February 10, 1932 when the Letdown Demineralizer System parametet's were restored to the values of the FSAR.
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