ML19291A691

LER 79-018/01T-0 on 790427:PS-1-1622A & B Reactor Bldg Suppression Chamber Alarm Pressure Switches & Transmitter Were Valved Out.Caused by Personnel Error.Valves Reopened & Instrument Surveillance Procedures Reviewed

ML19291A691
Person / Time
Site:	Quad Cities
Issue date:	05/11/1979
From:	Willemsem B COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19291A686	List: ML19291A685 ML19291A691
References
LER-79-018-01T, LER-79-18-1T, NUDOCS 7905240605
Download: ML19291A691 (3)

Text

(111)

LICENSEE EVENT REPORT S .CONTROLBtCCCl l l l l l l@ (PLEASE PRINT oR TYPE ALU AEQUIRED INFORMATION) l JJIhlbl LATSdl@

l IolilIi!tl01AlD!1lhl150 7 8 9 LICENSEE CGCE 14 l0 l O! -l O!O l0 l-l0l0l O!hl LICENSE NUMdEH h 4 l1 LICENSE 20 l1 l1TYPE CON'T 7

o 1 8

3$n$ 60l L l@l 0 l 5COCK 61 l 0ETl NVV8ER 010 l2 15*A1462@l0I412I7I7lo EVENT OATE

@l0 l's REPQRT 14 75 11 11 DATE 17 Iol@ d3 EVENT DESCRIPTION AND PROB ABLE CCNSECUENCES h '

o 2 l While installino Reactor Buildino Suppression Chamber alarm cressure switches. l o 3 l PS-1-1622A and B were inadvertantly valved out for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> on April 26 and for 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> I

[T[T] l on April 27, 1979 (T.S.3.7.A.3). These switches provide the automatic mode of operation l 0 s I of the Reactor Building-to-Suppression Chamber vacuum breakers A0-1-1601-20A and B. l l o le, I l Post-Accident monitoring torus pressure indicating transmitter, PIT-1-1623 was also I o , l valved out. Orywell pressbre indicator was operational at all times. The vacuum l o g g breakers were remotely-manually operable at all times from the control room. l SYSTEM CAUSE CAUSE COMP. VALVE CODE CODE SveCODE COMPONENT CODE SUSCODE SU8 CODE g l Sl 0l@ l A l@ l Cl@ l Vl A l L lV lE lX l@ W@ y @

10 7 8 9 11 12 13 is is 20

,._ SEQUENTI AL OCCURRENCE REPORT REVISION LER EVENT YE AR REPORT NO. CODE TYPE N O.

O sug/RO 17 19 I at a'

,_ 21 22 l-l 2J l011181 24 26 1/l 27 I of il 28 29

[IJ 33 l-l 31 d

32 K N A Or CN PLANT HOURS S S iT POR 8. SUPPLIE MANUFACT RER lJJH l@l34Z l@ l35Z l@ d'@

36 l0l0l010l 31 40 lY l@

el l42 N lh l43 N lh l44 Z l 9 l 9l 479lh CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h 1 o l The cause of this occurrence was Oersonnel error. The immediate corrective action was 1

[,._j,1,j l to reopen the valves returning the Reactor Buildino-to-Sucoression Chamber vacuom I p;y q l breakers to normal operability. Routine surveillance procedures were reviewed to assurel gl that only one switch is valved out during testing. Personnel have been instructed as tol gl the consequences of this event. l 7 8 9 80 SA S  % POWER OTHER STATUS SO RY DISCOVERY DESCRIPTION 1 s (_,Ej@ l 0 l 9 l 7 l@l NA l lAl@l Ooeratlonal Event j ACTIVITY CONTENT RELEASE AMOUNT OF ACTIVITY LOCATION OF RELEASE y l Zl @D OF RELEASE l Z l@l NA l NA l 7 8 9 to 11 44 45 83 PERSONNEL EXPOSURES NUMBER TYPE DE SCRIPTtCN NA l TIT]

l 0l 0l 0l@l Zl@l

2

l PEnSONN E t iN;u'R iES NUMBER DESCRIPTION 7

1 8 8 9 l 0l 0l 0lhl 11 12 NA 30 l

LOSS TvPE OF OR DAVAGE TO FAC:L1TY @

oESCRiPTiON Q l8 Zl@l NA 7905240 f l 7 9 10 80 PUBLICITY NRC USE ONLY ISSUE D DESCRIPTION

• 7 2

o8 9l Nlhl to NA l 68 69 lllIlllIIIIIlI 83* 3

~

~~

NAME OF PREPARER B. Willemsem PHONE: 309-654-2241 ext. 171  ?,

1. LER NUMBER - LER/R0 79-18/01T-0

11. LICENSEE NAME - Commonwealth Edison Company Quad-Cities Nuclear Power Station Ill. FACILITY NAME - Unit One IV. DOCKET NUMBER 050-254 V. EVENT DESCRIPTION While installing Reactor Building Suppression Chamber alarm pressure switches, under work request number 168-79, pressure switches PS 1622A and B, and pressure transmitter PIT-1-1623 were valved out.

Pressure switches PS-1-1622A and 8 provide for the automatic mode of operation of the Reactor Building-to-Suppression Chamber vacuum breakers, A0-1-1601-20A and A0-1-1601-208. Pressure indication transmitter, PIT-1-1623, provides for post accident monitoring of torus pressure.

Subsequently, the requirements of Technical Specification 3 7.A.3 were not met when these instruments were valved out for one hour on April 26 and for three hours on April 27 VI. PROBABLE CONSEQUENCES OF THE OCCURRENCE The consequences of the occurrence were minimized by . short duration of the inoperability of the vacuum breakers and by the fact that the vacuum breakers were at all times remotely-manually operable from the Control Room, and the drywell pressure indicators were operational at all times. No events took place during this time which required the automatic functioning of the vacuum breakers, or the need to monitor suppression chamber pressure. Drywell-Torus Differential Pressure was maintained above Technical Specification limits. The reactor and containment were not placed in an unsafe condition.

Vll. CAUSE The cause of the occurrence was personnel error. The personnel on the job were unaware of the fact that the work was related to any Technical Specifications. A probable cause contributing to this occurrence was that the work request was not coded ' Safety Related' .

The work request only involved the addition of an alarm switch and the potential of an error was not forseen.

Vill. CORRECTIVE ACTION The innediate corrective action was to reopen the valves, returning the reactor building-to-suppression chamber vacuum breakers to normal operability. Other corrective action included coding the incompleted work request ' Safety Related' and to scheduling it, more appropriately, for completion during a unit outage. A review of instrument survell-lance procedure was completed to assure that only one pressure switch would be valved out during routine instrument surveillances.

The Master instrument Mechanic has instructed the personnel involved, in the ramifications of valving both suppression chamber pressure switches out. Signs will be posted instructing personnel not to valve out more than one instrument at a time while performing maintenance or surveillance work.