ML17305A730
| ML17305A730 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 05/02/1990 |
| From: | James M. Levine ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 1-SR-89-009, 1-SR-89-9, 192-00657-JML-T, 192-657-JML-T, NUDOCS 9005080083 | |
| Download: ML17305A730 (10) | |
Text
ACCELERATED ISTIUBUTION DEMObRATION SYSTEM l
REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)
ACCESSION NBR:9005080083 DOC.DATE: 90/05/02 NOTARIZED:
NO DOCKET FACIL:STN-50-528 Palo Verde Nuclear Station, Unit 1, Arizona Publi 05000528 AUTH.NAME AUTHOR AFFILIATION LEVINE,J.M.
Arizona Public Service Co.
(formerly Arizona Nuclear Power RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
SUBJECT:
Special Rept 1-SR-89-009,Suppl 1:on 890907,radiation monitoring unit inoperable in excess of 72 h.
DISTRIBUTION CODE:
IE22D COPIES RECEIVED:LTR ENCL SIZE:
TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.
NOTES:
05000528 RECIPIENT ID CODE/NAME PD5 LA PETERSON,S.
INTERNAL: ACNW AEOD/DOA AEOD/ROAB/DSP NRR/DET/ECMB 9H NRR/DET/ESGB 8D NRR/DLPQ/LPEB10 NRR/DREP/PRPBll NRR/DST/SICB 7E NRR/DST/SRXB 8E RES/DSIR/EIB EXTERNAL: EG&G STUART,V.A LPDR NSIC MAYS,G NUDOCS FULL TXT NOTES:
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1 RECIPIENT ID CODE/NAME PD5 PD CHAN,T ACRS AEOD/DSP/TPAB DEDRO NRR/DET/EMEB9H3 NRR/DLPQ/LHFB11 NRR/DOEA/OEAB11 NRR/DST/SELB 8D NRR/DST/SPLB8D1 RG 'I E "'
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1 NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASIEI CONTACT THEDOCUMENTCONTROL DESK, ROOM PI-37 (EXT. 20079) TO ELIMINATEYOUR NAMEFROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEEDl TOTAL NUMBER OF COPIES REQUIRED:
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)J f'I' I
Arizona Public Service Company PALO VERDE NUCLEAR GENERATING STATION P.O. BOX 52034
~
PHOENIX. ARIZONA85072-2034 JAMES M. LEVINE YtCC >RESIOENT NCC<5AR PAOOVCTION 192-00657-JML/TRB/SBJ May 2, 1990 U.
S. Nuclear Regulatory Commission NRC Document Control Desk Washington, D.C.
20555
Dear Sirs:
Subject:
Palo Verde Nuclear Generating Station (PVNGS)
Unit 1 Docket No.
STN 50-528 (License No. NPF-41)
Special Report 1-SR-89-009 File'9-0 0-404 Attached please Supplement Number 1 to Special Report 1-SR-89-009 prepared and submitted pursuant to Technical Specification 3.3.3.8 ACTION 42(b) and 6.9.2.
This report discusses a radiation monitor inoperable for greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
Additionally, a copy of this report is being sent to the Regional Administrator.
If you have any questions on this matter, please contact Mr. Thomas R.
- Bradish, Compliance Manager at (602) 393-2521.
Very truly yours, JML/TRB/SBJ/tlg Attachment CC:
W. F.
Conway J. B.'Martin D. H.
Coe T. L. Chan A. C. Gehr A. L. Gutterman INPO Records Center (w/attachment) 9005080083 900502 PDR ADOCK 05000528 C;
I
PALO VERDE NUCLEAR GENERATING STATION Radiation Monitoring Unit Inoperable for Greater Than 72 Hours License No. NPF-41 Docket No.
STN 50-528 Supplement 1 to Special Report 1-SR-89-009 This Special Report is submitted in accordance with Technical Specifications 3.3.3.8 ACTION 42(b) and 6.9.2 for an event in which the Plant Vent High Range Effluent Monitor (RU-144) was inoperable for greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
The 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> was exceeded at approximately 0623 MST on September 10, 1989
'alo Verde Unit 1 was in a refueling outage with the core off-loaded to the spent fuel pool at the time of this event.
At approximately 0623 on September 7,
- 1989, the plant vent low and high range effluent monitors (RU-143 and RU-144) were declared inoperable because the Skid Mounted Indication and Control (SMIC) Unit for the low range monitor was not operating properly.
Pursuant to Technical Specification 3.3.3.8 ACTION 37, the Preplanned Alternate Sampling Program (PASP) was initiated at approximately 0705 MST on September 7,
1989 and continued until the radiation monitors were declared operable.
RU-143 and RU-144 radiation monitors work as a pair, with the low range monitor normally operating and the high range monitor in standby.
When the low range monitor reaches a predetermined
- setpoint, the high range monitor starts and the low range monitor goes to standby.
The high range monitor provides tracking of radioactive effluents during postulated accident scenarios.
The high range monitor must be declared inoperable when the low range monitor is inoperable.
Each radiation monitor has a detector communicating with a microcomputer.
The microcomputer for RU-143 is located in the post accident monitoring unit (PAMU).
Routine radiation information in the microcomputer can be accessed at the radiation monitor using the SMIC unit.
A portable indication and control (PIC) unit can be plugged into the microcomputer to access information, Remote access to the microcomputer is through the minicomputer.
Actuations of the radiation monitor are processed by the minicomputer.
The SMIC inability to communicate with the microcomputer was intermittent.
Maintenance monitored RU-143 SMIC performance daily after the radiation monitor was declared inoperable.
As part of the troubleshooting, the CPU board and system board for the SMIC were replaced.
After the board chargeout, SMIC again operated intermittently.
The system board was then removed and reinserted.
SMIC operated properly after this readjustment.
The intermittent inability of SMIC to communicate with the microcomputer has been attributed to the system board zero insertion connecting socket.
The connecting socket did not ensure solid contact at all times.
Since the condition does not effect the operability of the radiation monitor, no additional corrective actions for this problem are necessary.
The old sockets will be removed whenever it is necessary to replace a system board and new sockets are available.
New system boards procured have a different connecting socket.
Special Report 1-SR-89-009-01 Page 2
An engineering evaluation completed on October 10, 1989 determined that the inability of RU-143 SMIC to communicate with the microcomputer did not affect the operability of the radiation monitor.
SMIC is only used for accessing data.
The radiation monitor was capable of initiating the required annunciations and actuations (see attached drawings).
Therefore, RU-143 and RU-144 were declared operable at approximately 1300 MST on October 13, 1990.
In addition, to preclude unnecessarily declaring radiation monitors inoperable, a engineering evaluation has been completed that identifies the minimum requirements for Technical Specification radiation monitors to be operable.
l II'(
SMXC Skid Mounted Indicating Unit located at monitors MONITORS I
P. -141/1 2
Ru-143/144 Ru-145/ 146 MICRO-COMPUTER t(EPIC For'.
Ru-141/142 Ru-143/144 Indicating unit connected to micro in PAMU SYSTEM Console (DECVRXTER)
Controller/Brains of the RMS system (1 per monitor )
Ru-141/142/143/144 located in PAMU Cabinet Ru-145/146 located on 120'f Control Bldg.
I l
MXHX"COMPUTER (DEC)
NERXC For '. Ru-145/146
- only, Xndicating unit located outside Control Room 140'ccesses the Mini for shut-down/reboot operations and trend data, located in the EFF. Office Receives and stores info from each micro and sends data to DCU terminal and printer, located in Eff ~ Office SYSTEM PRINTER (TERMINET)
DCU Console CRT 8 keyboard for accessing mini-computer and providing alarm display and acknowledge Provides hard copy of all RMS events, located in C.R.
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