ML18136A187
| ML18136A187 | |
| Person / Time | |
|---|---|
| Site: | Surry, North Anna  |
| Issue date: | 11/05/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Proffitt W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| References | |
| NUDOCS 7911160170 | |
| Download: ML18136A187 (6) | |
Text
e UNITED STATES NUCLEAR REGULATORY COMMISSION REGION II In Reply Refer To:
RII:JPO 50-338,-50-339
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50-405
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50-281 101 MARIETTA ST., N.W., SUITE 3100 ATLANTA, GEORGIA 30303 NOV 5 1979 Virginia Electric and Power Company Attn:
W. L, Proffitt Senior Vice President, Power P. O. Box 26666 Richmond, Virginia Gentlemen:
23261 This Information Notice is provided as an early notification of a possibly significant matter. It is expected that recipients will review the information for possible applicability to their facilities.
No specific action or response is requested at this time.
If further NRC evaluations so indicate, an IE Circular, Bulletin, or NRR Generic Letter will be issued to recommend or request specific licensee actions.
If you have questions regarding the matter, please contact the Director of the appropriate NRC Regional Office.
Enclosures:
- 1.
IE Information Notice No. 79-26
- 2.
List of IE Information Notices Issued in the Last Six Months Sincerely,
~-z\\.~
James P. O'Reill~--
Director
Virginia Electric and Power Company cc w/encl:
W.R. Cartwright, Station Manager Post Office Box 402 Mineral, Virginia 23117 P. G. Perry Senior Resident Engineer Post Office Box 38 Mineral, Virginia 23117 W. L. Stewart, Manager Post Office Box 315
~urry, Virginia 23883
- e UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D. C.
20555 November 5, 1979 SSINS:
6870 Accession No:
7908220133 r
IE Information Notice No. 79-26 BREACH OF CONTAINMENT INTEGRITY
- Description of Circumstances:
On September 14, 1979, the Consumers Power Company (CPC) notified the NRC of discovery at the Palisades Nuclear Generating Plant of a valve misalignment that had resulted in containment integrity being breached for an indeterminate length of time.
While preparing to perform a Type "C" leak test between two manual valves in a 3" bypass line around the main 48" containment purge valve, plant personnel dis-covered that both of these manual isolation valves were locked in the open posi-tion.
These valves should have been locked closed.
Investigation by the licensee indicated that the valves may have been improperly positioned since April, 1978, when an efficiency test of the bypass line filters was performed.
The plant has operated at power for the major portion of that time period.
The valve misalignment had no actual impact on the public health.
However, in the event of a design basis accident wherein fuel damage and release of primary coolant inside the containment are postulated, the open valves would provide a significant path for a radioactive release from the containment.
The initial design purpose for the bypass system was to provide a long term hydrogen controJ1capability for the containment atmosphere following a design basis accident.-
It was intended that after approximately 30 days following an accident, when containment pressure and activity levels dropped sufficiently to permit venting, this system would be manually valved to vent the containment atmosphere, through high efficiency and charcoal filters, to the exhaust stack.
Thus the components in the bypass line beyond the two manual isolation valves were not designed for the severe service they would be exposed to with the valves open during the initial pressure surge of the design basis ac~ident, and signif-icant uncontrolled release would result.
High radiation in the vicinity of the bypass line would also make immediate closing of the manual isolation valves, even if identified as the source of leakage, an extremely hazardous operation.
The principal cause for this event was inadequacy of the procedures addressing proper use and positioning of these valves. The master containment integrity valve line-up checklist, which is performed prior to each startup from cold
!/ Current NRC requirements call for the use of hydrogen recombiners to control hydrogen buildup.
Palisades has recombiners installed.
IE Information Notice No. 79-26 November 5, 1979 Page 2 of 2 shutdown, did not include these valves.
- The filter efficiency test for the 3" bypass line did not adequately specify the final position of these valves, and t_his is the probable cause for the valves being left incorrectly positioned.
The valve misalignment represents a case where human factors in the form of inadequate procedures resulted in a loss of safety system function.
CPC has updated the above mentioned procedures to assure that proper positionin~
of these valves is addressed.
Concurrently, CPC is reviewing other paths from containment to assure that procedures and checklists are complete.
CPC has also hired a qualified consultant to perform an independent review for the same
___ purpose.
This Information Notice is provided as an early notification of a significant occurrence. It is expected that recipients will review the information for possible applicability to their facilities.
No written response is required.
If you desire additional information regarding this matter, contact the Director of the appropriate NRC Regional Office.
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e IE Information Notice No. 79-26 November 5, 1979 Information Notice No. 79-26 79-25 79-24 79-23 79-22 79-21 79-20 (Rev. 1) 79-20 79-19 (Correction -
Enclosure) 79-19 79-18 LISTING OF IE INFORMATION NOTICES ISSUED IN LAST SIX MONTHS Subject Breach of Containment Integrity Reactor Trips at Turkey Point Units 3 and 4 Overpressurization of Containment of a PWR Plant After a Hain Steam Line Break Emergency Diesel Generator Lube Oil Coolers Qualification of Control Systems Transportation and Commer-cial Burial of Radioactive
, Materials NRC Enforcement Policy NRC Licensed Individuals NRC Enforcement Policy NRC Licensed Individuals Pipe Cracks in Stagnant Borated Water Systems at PWR Plants Pipe Cracks In Stagnant Borated Water Systems At PWR Plants Skylab Reentry Date Issued 11/5/79 10/1/79 10/1/79 9/26/79 9/17/79 9/14/79 9/11/79 9/7 /79 8/14/79 7 /18/79 7/17/79 7/6/79 Enclosure Page 1 of 2 Issued To All power reactor
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facilities holding OLs and CPs All power reactor facilities holding OLs and CPs All power reactor facilities holding OLs and CPs All Holders of CPs and OLs All Holders of CPs All Holders of OLs All Licensees as Supple-mental Information to IE Bulletin Nos. 79-19
& 79-20 All Holders of Reactor OLs and CPs and Production Licensees with Licensed Operators All Holders of Reactor OLs and CPs and Production Licensees with Licensed Operators All Holders of Reactor OLs and CPs All Holders of Reactor OLs and CPs All Holders of Reactor OLs
IE Information Notice No. 79-26 November 5, 1979 Information Notice No. 79-17
- -*79-16 79-15 79-14 LISTING OF INFORMATION NOTICES ISSUED IN LAST SIX MONTHS Subject Date Issued Source Holder Assembly Damage 6/20/79 Damage From Misfit Between Assembly and Reactor Upper Grid Plate Nuclear Incident at Three 6/22/79 Mile Island Deficient Procedures 6/7/79 NRC Position of Electrical 6/11/79 Cable Support Systems Enclosure Page 2 of 2 Issued To All Holders of Reac~or OLs and CPs All Research Reactors and Test Reactors with OLs All Holders of Reactor OLs and CPs All Power Reactor Facilities with a CP