ML20012C681

LER 90-010-00:on 900216,containment Radioactive Iodine Monitor Radiation Monitoring Sys Channel Failed Low.Caused by Design/Equipment Concerns.Sys Design Mods Will Be Implemented to Eliminate ESF Actuation signals.W/900314 Ltr

ML20012C681
Person / Time
Site:	Salem
Issue date:	03/14/1990
From:	Miller L, Pollack M Public Service Enterprise Group
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-90-010, LER-90-10, NUDOCS 9003230049
Download: ML20012C681 (4)

Text

, g ,; ,e 7 l

~

~

Public Service Electric &nd Gas Company P.O. Box 236 Hancocks Bridge, New Jorsey 08038 Salem Generating Station l[- )

p March 14, 1990 I i

c j.

U. S. Nuclear Regulatory Commission f'V a ' Document Control Desk li-1, Washington ~, DC 20555 '

j,

Dear Sir:

SALEM GENERATING STATION- ,

LICENSE NO. DPR-75 DOCKET NO. 50-311 UNIT NO. 2

' LICENSEE EVENT REPORT 90-010-00 This. Licensee Event Report is being submitted pursuant to the requirements of the Code of Federal Regulations 10CFR

' 50.73 (a) (2) (iv) . This report is required within thirty (30) days '

of-discovery, i

,e b

Sincerely yours,

.y a e S L. K. Miller General Manager -

Salem Operations

g. MJP:pc -

Distribution 9003230049 900314 PDR ADOCK 05000311 9

b S PDC

{f The Energy People IN f68bune es s

une ses va muetsAn neou6Avon, esmeemmes.

• • ', Annoveo one no sim.eim

• '"*"8'"

UCENSEE EVENT REPORT (LER) ease 6ery masse m oocart numeen m re Saleen Generating Station - Unit 2 0l5l0l0l0l3l1l1 1 lOpl 0l 3 i vrrte see ESP Actuation: Containment Ventilation Isolation Due To Equitument/ Design Concerns eveert mate e Lea muusen e mesent oAtein ornen enciLmes urvolveo si es0effM OAV YEAR vtAR "$In'6 $ e#04tn ' Dav vtAn . ACittiv hans.e D0Catt? Nuesotatoi 0l5l0l0l0 1 l l

~ ~

Ol2 1 l6 9 0 cil 0 0 l 1l0 0l 0 0l3 1l4 9l0 0 l 510 l 0 l 0 l l l

,,,,,,,,,, two asecar is suomitreo evneuAnt to twc neouinewswis oe se Cea 6 <Cn e w .a == sel=-aw nn  ;

esos e g ,,,,,, , , , , , ,,,,,n., ,,,,,,

gnei _

se.esemmin so.aswm es3swen s 7 Jiw 1 l 0go se anwmm _

m seweni ,,,,,,

nesseinen.c

_ gj,a7,7,ja,g,,,

se asswmiw so.tswano sessman.mnAi ,isens

g. _

se asswn H=i maswmm _

essowan snoi w menwmm waswanw eesswan.i  !

' LICatete C0stT ACT 90A TMie Llh till Ae.t vit.. 0 t .v se. l ARiaCODE M. J. Pollack - 1.ER Coordinator 6l 0 l9 3l3l9 l- 1 201 1 2l 2 C0esPLif t Oest List poa E ACM CoasPoweNT F AiLURE oneC#eto IN TMao Repont tisi  !

T d CAUet Sv8?tu COMP 0htNT $"[g A C. R o pp g CAust 8 STtw COMP 0hth? "#Mf r 87d"l,'E ,Y : g y, B I lL DlEIT l V il 1 1l5 Y l l l l l l l .

I I I I l l l l l t t l l l M eupplemtN' AL mtPont EMPtCT80 tie' MONTH DAY vpAR ,

YES t!! pen. remoen LKPLCTRO $Ventt$$lON DA tti kO l l l A . .C, _ . . .w _. . . . _.._. _. w _ _ .i e i On February 16, 1990 at 1053 hours0.0122 days <br />0.293 hours <br />0.00174 weeks <br />4.006665e-4 months <br />, the 2R12B (Containment Radioactive Iodine Monitor) Radiation Monitoring System (RMS) channel failed low.

This resulted in an Engineered Safety Feature (ESP) actuation signal for Containment Purge / Pressure-Vacuum Relief (CP/P-VR) System isolation. The channel was declared inoperable. The root cause of this event has been attributed to design / equipment concerns.

Investigation did not identify any specific problem (s) which would have directly caused the 2R12B channel failure. The type detector system used for the Salem Unit 2 RMS channels is manufactured by Victoreen. Periodic problems with this system have been experienced as indicated in prior LERs (e.g., 311/89-002-00, 311/90-001-00, and 311/90-009-00). The 2R12B channel was successfully functionally tested and the channel was declared operable on February 21, 1990. As indicated in LER 311/90-009-00, Engineering has investigated the concerns with the Unit 2 RMS channels. It is anticipated that several

-Dystem design modifications will eliminate the spurious ESF actuation signals. One of these design modifications is the installation of an uninterruptable power supply (UPS), currently scheduled for June 1990. The plans for completion of these modifications are included in the current PSE&G Living Engineering Plan for the RMS system.

O?*"' **

0  !

m LICENSEE CVENT REPORT (LER) TEXT CONTINUATION l i-Salen Generating Station DOCKET NUMBER LER NUMBER PAGE I Unit 2 5000311- 90-010-00 2 of 3 PLANT AND___ SYSTEM IDENTIFICATION:

Westinghouse - Pressurized Water Reactor j Energy Industry Identification System (EIIS) codes are identified in j the text as lxxl l

IDENTIFICATION OF OCCURRENCE:

Actuation of an Engineered Safety Feature, Containment Purge .

L Pressure-Vacuum Relief isolation, due to design / equipment concerns L i Event Date: 2/16/90 1 Report Date: 3/14/90 This report was initiated by Incident Report No.90-125.

CONDITIONS PRIOR TO OCCURRENCE:

l Mode 1 Reactor Power 100% - Unit Load 1160 MWe DESCRIPTION OF OCCURRENCE: i On February 16, 1990 at 1053 hours0.0122 days <br />0.293 hours <br />0.00174 weeks <br />4.006665e-4 months <br />, the 2R12B (Containment Radioactive Iodine Monitor) Radiation Monitoring System (RMS) (ILI channel failed low. This resulted in an Engineered Safety Feature (ESP) actuation signal for Containment Purge / Pressure-Vacuum Relief (CP/P-VR) System IBFI isolation. The channel was declared inoperable.

APPARENT CAUSE OF OCCURRENCE:

The root cause of this event has been attributed to design / equipment concerns. Investigation did not identify any specific problem (s) which would have directly caused the 2R12B channel failure.

The type detector system used for the Salem Unit 2 RMS channels is manufactured by Victoreen. Periodic problems with this system have been experienced as indicated in prior LERs (e.g., 311/89-002-00, 311/90-001-00, and 311/90-009-00).

l ANALYSIS OF OCCURRENCE:

l l'

The 2R12B RMS channel monitor's the radioactive iodine gas content of the Containment atmosphere. By design, either a "high" alarm signal or a low channel failure will cause the automatic isolation of the CP/P-VR System.

Air samples are pulled from the Containment atmosphere through a filter paper which continuously moves past the 2R11A (Containment Radioactive Particulate Monitor) detector. The air sample then passes through a charcoal cartridge (monitored by the 2R12B monitor) and is then mixed into a fixed shielded volume where it is viewed by

x-

. . 4' ----

A 4 l * . , LICENSEE EVENT REPORT (LER) TEXT CONTINUATION S21em Generating' Station DOCKET NUMBER LER NUMBER PAGE l Unit 2 5000311 90-010-00 3 of 3 i- .

ANALYSIS OF OCCURRENCE: (cont'dl f

the 2R12A (Containment Radioactive Noble Gas Monitor) monitor. The air sample is-then returned to the Containment.

Several area radiation monitors, in addition to the 2R11A and 2R12A l monitors, are.used to corroborate the 2R12B channel's indications.  !

The corroborating area radiation monitors do not have isolation l capabilities; they only have alarm capability. None of these channels indicated any abnormal activity during this event. ,

l  !

The 2R12A Containment Radioactive Noble Gas monitor is the channel ,

, taken credit for by the accident analysis for monitoring containment '

airborne activity in order to mitigate the consequences of an accident. The 2R12A monitor has the capability of automatic isolation of the CP/P-VR System. It remained operable during the course of this event and did not indicate any abnormal Containment i airborne activity, g During this event, RCS leakage within containment did not increase nor was-there any indication of increasing Containment activity as .

indicated by the 2R12B corroborating RMS channels. Therefore, this. )

event did not affect the health or safety of the public. However, i due to the automatic actuation of an ESF system, this event is ]

reportable in accordance with Code of Federal Regulations 10CFR 50.73 (a) (2) (iv) .

CORRECTIVE ACTION:

The 2R12B channel was successfully functionally tested and the channel was declared operable on February 21, 1990.

As indicated in LER 311/90-009-00, Engineering has investigated the concerns with the Unit 2 RMS channels. It is anticipated that several system design modifications will eliminate the spurious ESF actuation signals. One of these design modifications is the installation of an uninterruptable power supply (UPS), currently ,

scheduled for June 1990. The plans for completion of these modifications are included in the current PSE&G Living Engineering >

Plan for the RMS system. t

, General Manager -

Salem Operations MJP:pc l SORC Mtg.90-022 i

e - . --__ _ _ _ - - _ _ _ _ -