ML18093B432

LER 89-002-00:on 890105,radiation Monitoring Sys Spiked High Resulting in Actuation Signal for Containment Purge/Pressure Vacuum Relief Sys Isolation.Caused by Equipment Problem. Channel Back Plane Contacts on Modules cleaned.W/890201 Ltr

ML18093B432
Person / Time
Site:	Salem
Issue date:	02/01/1989
From:	Miller L, Pollack M Public Service Enterprise Group
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
LER-89-002, LER-89-2, NUDOCS 8902090480
Download: ML18093B432 (4)

Text

NRC For"' 3111 U.S. NUCLEAR REGULATORY COllWllllON 19-83) Al'PROVED OMll NO. 31 ll0--01 CM EXPIRES; 8/31 In LICENSEE EVENT REPORT (LERI FACILITY NAME 111 DOCKET NUMllER 121 I ..... (31 Salem Generating Station - Unit 1 TITLE l*I

!o 15 Io Io Io I 217 I ii 1 !oF o I 3 ESF Actuation, Cont. Purge/Pressure - Vac. Relief_ Isolation, Due T-0 An Equip. Problem

~VENT DATE 1111 LER NUMBER 1111 REPORT DATE 171 OTHER FACILITIES iNVOLVED Ill MONTH DAY YEAR YEAR it SE~~~~~~AL \t ~~~':.~ MONTH DAY YEAR FA.Cl LITY NAMES DOCKET NUMBERISI 0151010101 I 'I o I 1 ol s s 9 s 19 - o lo I 2- o I o o 12 ol 1 s 19 THll REPORT II IUIMITTED PURIUANT TO THE REOUIREMENTI OF 10 CFR §: IC/tock one or mOl"f of th* following) 1111 OFERATING MODE Ill 73.71lbl ll0.3111cll1 I ll0.311cll21 -- ll0.73llll21M ll0.731111211*111 73.711*1 OTHER (5/>>0/fy in Ab,,,..,t l>>low *ntl In T*llt, NRC Form

• litlll=

20.-11111111111 ll0.73111121111 ll0.73llll2lMllllAI 366AJ 20.-11111111¥1 20.-l11111M ll0.731111211111 ll0.73111121°11111 -

LICENSEE CONTACT FOR THIS LER 1121 ll0.7311ll21Mllllll ll0.7311112llxl NAME TELEPHONE NUMBER' AREi!. CODE M. J. Pollack - LER.Coordinator *61 0 19 3 I 3 1 9 1..:. 1 4 1O 12 i2 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DEICRllED IN THll REPORT 1131

. CAUSE SYSTEM COMPONENT MANUFAC*

TUR ER B I1L Yes I I I I I I I I I I I I I I I I I I I I I IUl'PLEMENTAL REPORT EXPECTED 1141 MONTH DAY Y~AR EXPECTED n YES llf yn, *complm EXPECTED SUtlAllSSION DATE/

SUllM1$SION DATE 1161 I *I I ARTRACT (Limit ta 1400 _ . , I . *.. *PPrDlllm*lfly fiftHn 1/ng/1*,,,.<0 ty,,.writron /inn) 11111 On January 5, 1989 at 0419 hours0.00485 days <br />0.116 hours <br />6.92791e-4 weeks <br />1.594295e-4 months <br />, the 1R41C (Plant Vent Noble Gas Monitor) Radiation Monitoring System (RMS) channel began spiking high (offscale). This resulted in an actuation signal for Containment Ventilation !~elation as well as automatic closure of the Waste Gas Decay Tank Vent Cont~ol Valve, 1WG41. Technical Spe~ification Table 3.3-13 Action Statement 31 was subsequently entered. The root cause of this event has been attributed to an equipment problem. The channel back plane was found corroded~ the gold contacts were discolored. The back plane contacts on all the modules in both the local and remote 1R41C channel monitors were cleaned. The channel was subsequently returned to service, but not declared operable for two days while close observation of the channel func.tioning was conducted. Technical Specification Action Statement 31 was exited on January 7, 1989 at 2200 hours0.0255 days <br />0.611 hours <br />0.00364 weeks <br />8.371e-4 months <br /> when the channel was declared operable.

Engineering had inititated, prior to this ev~nt, an investigation to provide a permanent fix to the problem(s) associated with the Victoreen model back plane. This investigation is continuing.

NRC Form Jee 19-831 -------------------------------0i y

--- ---------------------~---**-------- - *-* ------- *------- ----- --------------------- _* __

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION Salem Generating Station DOCKET NUMBER LER NUMBER PAGE J}_:g._:i,_:t:_J.___________________________ ---- 5_0_Q_Q_?_7_~------ - ---~-<J ~_Q_Q_?_:- Q_Q________2_g~-- ----

Westinghouse - Pressurized Water Reactor Energy Industry Identification System (EIIS) codes are identified in the text as {xx}

Actuation of an Engineered Safety Feature (ESF) signal, Containment Purge Pressure-Vacuum Relief isolation, due to an equipment problem Event Date: 1/05/89 Report Date: 2/01/89 This report was initiated by Incident Report No.89-007.

~ Q_lfD J:1'~_9l'{S __e_}5_I_QR _ _T_O___Q~_ 9_TJ~-R~NC E :

Mode 1 Reactor Power 100% - Unit Load 1155 MWe DESCRIPTION OF OCCURRENCE:

On January 5, 1989 at 0419 hours0.00485 days <br />0.116 hours <br />6.92791e-4 weeks <br />1.594295e-4 months <br />, the 1R41C (Plant Vent Noble Gas Monitor) Radiation Monitoring System (RMS) {IL} channel began spiking high (offscale). This resulted in an actuation signal for Containment Purge/Pressure Vacuum Relief System {BFl isolation as well as automatic closure of the Waste Gas Decay Tank Vent Control Valve, 1WG41. Technical Specification Table 3.3-13 Action Statement 31 was subsequently entered.

Technical Specification Table 3.3-13 Action Statement 31 states:

"With the number of channels OPERABLE less than required by the Minimum Channels OPERABLE reauirement, the contents of the tank(s) may be released to the environment provided that prior to initiating the release:_

a. At least two independent samples of the tank's contents are analyzed, and

b. At least two technically qualified members of the Facility Staff independently verify the release rate calculations and discharge valving lineup; Otherwise, suspend release of radioactive effluents via this pathway."

The root cause of this event has been attributed to an equipment problem. The channel back plane was found corr6ded; the gold contacts F2re discclo:ced.

---

e LICENSEE EVENT REPORT (LER) TEXT CONTINUATION Salem Generating-Station DOCKET NUMBER LER NUMBER PAGE

!!_h_;i t---1________ _:__________________?_Q_Q_O_~J-~---________ ?~_:-_Q_Q_~_-.-_Q_Q__ _____ 3 __ Qf_ -~---- _

blJALY~J!?_Q_f_QC_<;_VJ.5.~-~_N.~E:

Isolation of the Containment Purge/Pressure - Vacuum Relief System is part of the design Engineered Safety Features (ESFs). It mitigates the release of excessive quantities of radioactive material to the environment after a design base accident.

The 1R41C channel monitors the plant vent effluent releases for radioactive noble gases via representative sampling. The ESF actuation feature of Containment Purge/Pressure Vacuum Relief System isolation is redundant to the 1R12A channel which monitors Containment noble gai activity. In addition to the ESF function, the channel will cause the isoiation of the 1WG41 valve.

As indicated in the Apparent Cause of Occurrence section, the iso}ation signal was the result of an equipment problem resultinq in a high channel spike. It was not the result of high plant vent activity. Therefore, this event did not affect the health or safety of the public. However. this event is reportable in accordance with the Code of Federal Regulations 10CFR 50.73(a) {2) {iv).

The back plane contacts on all the modules in both the local and remote 1R41C channel monitors were cleaned. The channel was.

subsequently returned to service, but not declared operable for two days while close observation of the channel functioning was conducted. Technical Specification Action Statement 31 was exited on January 7, 1989 at 2200 hours0.0255 days <br />0.611 hours <br />0.00364 weeks <br />8.371e-4 months <br /> when the channel was declare~ operable.

The back plane of the Victoreen model detector has proven to be a continuinq problem. This back plane is used in most of the Unit 2 RMS detectors. It has periodically caused detector inoperability.

Engineering had inititated, prior to this event, an investigation to provide a permanent fix to this probiem. This investigation is continuing_.

General Manager -

Salem Operations MJP:pc SORC Mtg.89-005

PS~G Public Service Elec11*ic and Gas Compa11/ P.O. Box E Hancocks Bridge, New Jersey 08038 Salem Generating Station February l, 1989 U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555

Dear Sir:

SALgM GENERATING STATION LICENSE NO. DPR-70 DOCKET NO. 50-272 UNIT NO. 1 LICENSEE EVENT REPORT 89-002-00 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.

Sincerely yours, L. K. Miller General Manager-Salem Operations MJP:pc Distribution