ML20209E400

Requests Info Re Operability of 12-inch Vacuum/Overpressure Relief Valves Per TMI Item II.E.4.2.Util Should Choose Opening Angle to Demonstrate Operability.Info Demonstrating Ability of Valve to Close Against LOCA Requested

ML20209E400
Person / Time
Site:	05000000, Diablo Canyon
Issue date:	04/29/1985
From:	Bosnak R Office of Nuclear Reactor Regulation
To:	Novak T Office of Nuclear Reactor Regulation
Shared Package
ML082410749	List: ML20209A984 ML20209B531 ML20209B624 ML20209B724 ML20209B847 ML20209B894 ML20209C131 ML20209C225 ML20209C292 ML20209C320 ML20209C516 ML20209C643 ML20209C669 ML20209C675 ML20209C698 ML20209C705 ML20209C710 ML20209C715 ML20209C720 ML20209C836 ML20209C847 ML20209C848 ML20209C876 ML20209C881 ML20209C908 ML20209C921 ML20209C969 ML20209C975 ML20209C981 ML20209C993 ML20209D004 ML20209D012 ML20209D018 ML20209D030 ML20209D038 ML20209D044 ML20209D045 ML20209D071 ML20209D089 ML20209D114 ML20209D127 ML20209D130 ML20209D135 ML20209D139 ML20209D146 ML20209D154 ML20209D211 ML20209D218 ML20209D230 ML20209D235 ... further results
References
FOIA-86-197, RTR-NUREG-0737, RTR-NUREG-737, TASK-2.E.4.2, TASK-TM NUDOCS 8505060164
Download: ML20209E400 (2)

Text

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UNITED STATES s

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Docket Nos:

50-275/323 MEMORANDUM FOR:

Division of Licensing FROM:

Robert J. Bosnak, Acting Assistant Director Components & Structures Engineering Division of Engineering

SUBJECT:

SER FOR DIABLO CANYON 1 AND 2 ON CONTAINMENT ISOLATION DEPENDABILITY BY DEMONSTRATION OF CONTAINMENT PURGE AND VENT VALVE OPERABILITY NUREG 0737. ITEM II.E.4.2(6)

(DOCKETNOS. 50-275/323)

Plant Name:

Diablo Canyon Units 1 and 2 Docket Nos.:

50-275/323 Licensing Stage: OR and OL Responsible Branch: Licensing Branch No.3 Responsible Project Manager:

H. Schierling Review Status: Complete

Reference:

PG and E Letter No. OCL-85-145 dated April 10, 1985 to G. W. Knighton from J. C. Carroll regarding NUREG-0737 PGaG has not interpreted correctly the intent of the staff with regard to NUREG-0737, Item II.E.4.2 (6) in SSER-14. As PG&E has not provided information that demonstrates the operability of the 12 inch vacuum / overpressure relief valves at Diablo Canyon 1 and 2, the staff proposed an interium position with regard to the use of these valves. This interium position was to block the valves by mechanical means to an opening angle of 50' or less. The interium position was not meant to be a final resolution with regard to the demonstration of operability of the valves. The staff intended that PG&G provide infonnation that demonstrates the ability of these valves to close against the build up of pressure in containment during a LOCA.

In the interium it is acceptable to the staff to use the valves if they are limited to opening angles of 50* or less.

Contact:

R. Wright Ext. 28209 h0[0h D o

2

APR z a Nbl5 Thomas M. Novak PG8E should provide information that demonstrates the operability of these 12 inch valves. PG8E should choose the opening angle for which they want to demonstrate operability. The angle could be fully open (90*) or partially open ( 90').

If the information is not provided before the first refueling outage, then aftur start-up from the first refueling outage these valves should be closed and sealed shut during operating modes 1,2, 3 and 4.

Ro t. Bosnak, Acting Assistant Director Components & Structures Engineering Division of Engineering cc:

J. P. Knight V. Noonan G. Bagchi E. Reeves G. Knighton H. Scherling R. Perch 4

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