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MAR 131974 ~
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To:
James P. O'Reilly Directorate of Regulatory. Operations k
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Region I 631 Park Avenue King of Prussia, Pennsylvania 19406 From:
Jersey Central Power 5 Light Company Oyster Creek Nucle.nr Generating Station Docket #50-219 Forked River, New Jersey 08731 4
Subj ect :
Abnormal Occurrence Report No. 50-219/74/ 16
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Thc.fo11 cuing is a prcli.11 nary report being.cubmitted in cocpliance with the Technical Specifications paragraph 6.6.2.
Preliminary Approval:
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b.T. Carroll,J.
J Date cc: ' Mr. A. Gi.aihuss o
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9604170433'960213
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osAsut957Aymsymeure t%Arrvs
- Report Date:
3/7/ 74 Occurrencc:
3/7/74 1
Initial Writi:en Time of Report Date:
3/7/74 Occurren'ce:
1000
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OYSTER CREEK NL' CLEAR GENER\\ TING STATION FORKED RIVER, NEW JERSEY 08731 Abnormal Occurrence Report No. 50-219/74/16 IDENTIFICATION.
Violation of the Technical Specifications, paragraph 3.5. A.3, OF OCCURRENCE:
failure of four torus to drywell vacuum breakers to demon-strato oper:.bility during week'1y surveil 5ance testing.
This event is considered to be an abnormal occurrence as de-fined in-the Technical Specifications, paragraph _1,1sn r, p.
CONDITIO: S FRIOR TO OCCURPENCE:
X Steady State Power Routine Shutdown Hot Staidby Operation Cold Shutdown Load Chan;;cs During Refueling Shutdown Routing Pouer Operation Routine St.artup Other (Specify)
Operation
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T' o major plant paramters at the time of the event were as h
follows:
Power:
Core,1870 !L't Elec., 653 lEc Flow:
Recirc.,15.7 x 10" gpm Feed., 7.14 x 10' lb/hr Stach Gas:
33,000 pCi/see DESCRIPTIO.k On Thuredny, March 7,1974 at approxinntely 1000, while. per-0F CCCURRE;;CE:
forning weekly surreillance testing on the fourteen torus to drywell vacuuu breakers, it was found that four of the vacuum breakers (V-26-4, 5, 6, and 12) failed to demonstrate operability.
'lhis surveillance testing was being performed to satisfy the requirc:ent s of AEC Ictter (D. J. Storholt to R.11. Sims, dated January 30, 1974). This operchility testipn basically consisted g
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Abnormal Occurrence Report:No., 50-219/74/16 Page 2 l k of (1) checking each valve to be fully closed; (2) manually,
opening each valve to the fully open position; and (3) allowing
'it to close without assistance; and then (4) checking each valve to be fully closed.
V-26-4 was found to open freely, however, some hesitation in the valve movement was observed after the valve was released in the fully open position.
Once the closing motion began, the valve appeared to move freely to the fully seated position. Valves V-26-5, 6, and 12 all opened freely but required assistance in the closing movements.
Plant shutdown commenced as soon as thesc ' discrepancies were identified since the requirements of paragraph 3.5.A.3 of the
.Technicc1 Specifications couid not be satisfied.
By approxi-
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mately 1130, these valves were determined to again be operatile followin;; the application of successive manual'actuations to each valvo. Ilowever, based on the recent history of failures of the torus-drywell vacuum breaker valves, it was decided to i
continue with the plcnt shutdown and effect more permanent repairs on the valves following the shutdoun.
It is noted here i
that Valve V-26-9 was locked in the closed position on February 28, 1974 follouing its failure to demonstrate operability. This failure uns 2cp01ted as Abnormal Occurrence Report No.' 74-15, dated February 28, 1974.
APPAIENT cal'SH X
Desi gn -
P.rocedure
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OF OCCUnt'INCE:
l'anufact ura Unusual Service Condition Installation /
1ne. Envi.conmental
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Canstsuction Cosuoncnt Failure
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- 0;'e rat or Other (Srcei fy')
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Abnormal Occurrence R,cpott No. 50-219/75/16 Page-3
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It.is believed that these failures are attributed to excess friction in the valvo hinge pins. Similar failures have been
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reported as Abnormal Occurrence Report No. 74-11, dated February 15, 1974; Abnormal Occurrence Report' No. 74-14, dated February 22, 1974; and Abnormal Occurrence Report No.
74-15, dated February 28, 1974.
ANALYSIS OF The drywell-torus vacuum breaker system is required to prevent OCCURRENCE:
water oscillation in the downcomers due to low steam flow rates in'the downcomers and to provide' protection against negative pressure conditions in the containment vessel.
The signifi-cance of this event is minimal in that the inses of the Tech-(.
nical Specifientions state that this condition hnp no deliterinus
'e'ffect on negative pressure protection, since only about 25% of the availabic vacuum relief capacity is required for this pro-to ction.
'Ihe dryucil-torus vacuum breaker valves are required to bc closed during pipe break accidents (particularly small breal.s)
- g to assure proper steam condensation and prevent torus over-a 1
pressure. 1hese valves would have performed this function if
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required.
CORRECTIVE These valves (V-26-4, 5, 6, and 12) and Valvo V-26-9 wil'1 b'c ACr10N:
inspected following plant shutdown. The nature and extent of the repair work will be determined following these inspections.
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Abnormal.0ccurrence I R; port No. 219/74/16 Pego 4 aj
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Idditional corrective action being taken is as discussed in a letter to Mr. Robert J. Schemel from Mr. D. A. Ross, dated October 8,- 1973.. In that letter it was noted that an apparent
" growing" characteristic has been experienced with the teflon bushings at several facilities, including Oyster Creek. The bushing difficulty has been discussed,with Atwood 6 Morrill Company and a long-term solution is under investigation in con-junction with General Elcetric Company."
FAILURE DATA:
Basic valve data are as' follows:
Manufacturer - Atwood 6 Morrill Type - Check Valve Vent Arca - 1.75 square feet per valve
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