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LER 89-029-00:on 890714,intake Canal Level Sensor Channel Not Placed in Trip within 1 H of Inoperability.Caused by Operator Personnel Error.Procedures Developed for Stop Log installation.W/890813 Ltr
	ML18153B857
Person / Time
Site:	Surry
Issue date:	08/13/1989
From:	Kansler M; VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
	89-030, 89-30, LER-89-029, LER-89-29, NUDOCS 8908180363
	Download: ML18153B857 (6)
	v • d • e

e VIRGINIA ELECTRIC AND POWER COMPANY Surry Power Station P. 0. Box 315 Surry, Virginia 23883 August 13, 1989 U.S. Nuclear Regulatory Commission Serial No.: 89-030 Document Control Desk Docket No.: 50-280 016 Phillips Building License No.: DPR-32 Washington, D.C. 20555 Gentlemen:

Pursuant to Surry Power Station Technical Specifications, Virginia Electric and Power Company hereby submits the following Licensee Event Report for Unit 1.

REPORT NUMBER 89-029-00 This report has been reviewed by the Station Nuclear Safety and Operating Committee and will be reviewed by Safety Evaluation and Control.

Very truly yours, Enclosure cc: Regional Administrator Suite 2900 101 Marietta Street, NW Atlanta, Georgia 30323

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U.S. NUCLEAR REGULATORY COMMISSION e APPROVED 0MB NO. 3150-0104 EXPIRES: 4/30/92 ESTIMATED BURDEN PER RESPONSE TO COMPLY WTH *THIS*

INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD LICENSEE EVENT REPORT (LER) COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS AND REPORTS MANAGEMENT BRANCH (P-530), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555, AND TO THE PAPERWORK REDUCTION PROJECT (3150-01041, OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, OC 20503.

l FACILITY NAME (11 DOCKET NUMBER (21 PAGE 131 Surry Power Station, Unit 1 o I s I o I o I o I 2 18 I 0 , loF o 1s TITLE 141 Intake Canal Level Instrumentation Inoperable Due to Installation of Stop Logs in the Intake Structure and Channel Not Placed in Trip EVENT DATE (51 LER NUMBER 161 REPORT DATE 171 OTHER FACILITIES INVOLVED (Ill MONTH DAY YEAR VEAR rtm SEQUENTIAL NUMBER \(? REVtslON NUMBER MONTH DAY YEAR FACILITY NAMES DOCKET NUMBER(SI o1s1010101 I I 011 11 4 8 9 sl 9 - 0 12 19

- olo 0 Is _1 I 3 819 0151010101 I I THIS REPORT IS SUBMITTED PURSUANT TO THE -R~OUIREM.ENTS OF 10 CFR §: (Chtlck on* or more of th* following) (111 OPERATING N

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LICENSEE CONTACT FOR THIS LER (121 NAME TELEPHONE NUMBER AREA CODE M. R. Kansler, Station Manager COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (131 MANUFAC- MANUFAC-CAUSE SYSTEM COMPONENT CAUSE SYSTEM COMPONENT TURER TURER I I I I I I I I I I I I I I I I I I I I I I I I . I I I I SUPPLEMENTAL REPORT EXPECTED (141 MONTH DAY YE.AR EXPECTED

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DATE (151 NO I I I ABSTRACT (Limit to 1400 spaces, i.tJ., opproxim*tely fiftetm ~inglt1-spact1 typewritten lint11) (16)

On July 14, 1989, Unit 1 was operating at 18% power and Unit 2 was in cold shutdown. At 1210 hours0.014 days 0.336 hours 0.002 weeks 4.60405e-4 months , stop logs were installed in the Unit 2 "A" Circulating Water (CW) high level intake structure. Isolation of the intake structure resulted in the inoperability of an intake canal level sensor channel.

Technical Specification 3.7 requires that an inoperable channel be placed in a "trip" condition *within one hour.

Contrary to the above requirement, the inoperable channel was not placed in "trip" within one hour. Further review of this event determined that a similar event had occurred on July 2, 1989. The cause of these events has been attributed to personnel error. Operators failed to recognize that installation of the stop logs defeated a canal level channel.

The affected channel was identified as being inoperable and was placed in trip. The stop logs were subsequently removed from the 2A intake structure and the level sensor channel was restored to normal operation. Procedures will be developed for stop log installation.

NRC Form 366 (6-891

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NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (6-89) APPROVED 0MB NO. 3160-0104 EXPIRES: 4/30/92 ESTIMATED BURDEN PER RESPONSE TO COMPLY WTH THIS LICENSEE EVENT REPORT (LER) INFORMATION COLLECTION REQUEST: 60.0 HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH lP-530), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20565, AND TO THE PAPERWORK REDUCTION PROJECT (3160-0104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (1) DOCKET NUMBER. (2) LER NUMBER (8) PAGE 13)

YEAR ,',',',',' SEQUENTIAL .:::::::::* REVISION

,',:,',',' NUMBER :::::::::: NUMBER Surry Power Station, Unit 1 TEXT (If,,,,,,. /IIMC9 ia 19quir..t, u.. tlddltioM/ NRC Fann 31564 '*I 1171 1.0 Description of the Event On July 14, 1989, Unit 1 was operating at 18% power and Unit 2 was in cold shutdown. At 1210 hours0.014 days 0.336 hours 0.002 weeks 4.60405e-4 months , stop logs were installed in the Unit 2 "A" Circulating Water (CW) high level intake structure (EIIS-NN).

T~installation ~aS-..c.optrolled and documented by a Temporary M o d i f i ~ (TM) log. Intake canal level

~ __ sens.or channel III, for the CW intake canal (EIIS-CNL)

~level protection system (EIIS-JE), is located in the 2A intake structure. Isolation of the intake structure results in the inoperability of the level sensor. Technical Specification 3.7, Table 3.7-2, requires that if either unit is above 350 degrees Fahrenheit and 450 psig that an inoperable intake level channel be placed in a "trip" condition within one (1) hour. Contrary to the above requirement, the inoperable channel was not placed in "trip" at the time of the stop log installation. However, at 1521 hours0.0176 days 0.423 hours 0.00251 weeks 5.787405e-4 months , the 2A level trip intake structure was dewatered to below the level trip setpoint and the channel automatically generated a trip signal. At 1910 hours0.0221 days 0.531 hours 0.00316 weeks 7.26755e-4 months on July 14, the channel was manually placed in trip.

Further review of this event determined that a similar event had occurred earlier. On June 25, 1989, stop logs were installed in the 2A intake structure to support Unit 2 maintenance activities and were not removed until July 5. At the time of this stop log installation, both units were in Cold Shutdown (CSD).

Therefore, the operability of the canal level

'protection system was not required and the affected channel was not manually placed into the tripped condition. However, on July 2 Unit 1 conditions exceeded 350 degrees Fahrenheit and 450 psig. At this time, the 2A intake structure had already been dewatered which caused the channel to trip. However, it had not been manually placed in trip as required by Technical Specifications.

2.0 Safety Consequences and Implications The intake canal level protection system consists of four (4) safety-related level sensor channels installed in four of the eight high level intake NRC Form 366A (6-89)

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NFi'c FORM 386A U.S. NUCLEAR REGULATORY COMMISSION (6-89) APPROVED 0MB NO. 3150-0104 EXPIRES: 4/30/92 ESTIMATED BURDEN PEA RESPONSE TO COMPLY WTH THIS' LICENSEE EVENT REPORT (LERI INFORMATION COLLECTION REQUEST: 50.0 HAS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH (P-530), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555; ANO TO 1'HE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)

YEAR ,:::::::::: SEQUENTIAL ::::::::::: REVISION

NUMBER :::::::::: NUMBER Surry Power Station, Unit 1 TEXT (If man, 11pac. i& mquimd, uu additionM NRC Form 35S4'a/ (17) structures, one channel in each intake structure. Two intake structures with the level sensors are located on Unit 1 and the other two are located on Unit 2.

Actuation of three out of four channels on a low canal level of 23.5 feet will trip .both unit's turbines, close the CW and Service Water (SW) valves to the Component Cooling and Bearing Cooling Heat Exchangers (EIIS-HS), and close all condenser CW inlet and outlet valves (EIIS-ISV). These actuations are designed to ensure adequate intake canal inventory to provide SW flow to the Recirculation Spray Heat Exchangers. Each channel is provided with the capability of being placed in a tripped mode to allow for testing or continued unit operation with an inoperable channel while maintaining the required degree of redundancy.

At all times during these events, the remaining three channels were operable and capable of performing the required actions on low canal level. With one level channel inoperable and not in the trip mode, an additional channel failure in a non-conservative direction during an event could prevent an automatic initiation of the required CW and SW isolation.

However, control room indications and annunciators exist to alert operators of a low canal level condition. Abnormal, emergency, and annunciator response procedures exist that provide operator guidance on actions to be taken to manually establish the required canal isolation in the event of a low level condition. In addition, while the stop logs were installed, the intake structure was drained during most of the duration of both events. For the

'first event, the level channel was already in the tripped condition when the unit exceeded 350 degrees Fahrenheit and 450 psig. During the second event, the level channel was not in the trip mode for approximately three hours. Therefore, the above events did not affect the health and safety of the public.

3.0 Cause The cause of this event has been attributed to personnel error. Operators failed to recognize that installation of the stop logs on the unit in cold shutdown defeated a canal level channel on the NAC Form 366A (6-89)

NRl: FORM 366A U.S. N*ucLEAR REGULATORY COMMISSION

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E'l<<'IRES: 4/30/92 ESTIMATED BURDEN PER RESPONSE TD COMPLY WTH THIS LICENSEE EVENT REPORT (LER) INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH CP-530), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20566, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20603.

FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER C&I E )

Surry Power Station, Unit 1 TEXT fH more -,,.~ la 19qul,.,J, u* addlrioMI NRC Fann 3116A 'al I 171 operating unit. The stop logs-were installed in a Unit 2 structure which was not in operation at the time. This led to an inadequate review of the safety co'nsequences of the stop log installation. The temporary modification form requires that the need for a safety evaluation be reviewed if the modification will make an inoperable system operable or is installed on an operable system. The modification was interpreted as not meeting these requirements and the need for a safety evaluation was not reviewed. ..

Several other factors were identified as contribut*;i.ng to this error. Procedures did not exist for the installation of stop logs. Installation was controlled *by the use of the temporary modification log.

Operating startup checklists had not been updated to ensure the stop logs were removed on the opposite unit prior to unit conditions exceeding 350 degrees Fahrenheit and 450 psig.

4.0 Immediate Corrective Action(s)

The affected channel was identified as being inoperable and was placed in trip at 1910 hours on July 14.

5.0 Additional Corrective Action(s)

The stop logs were removed from the 2A Mifntake structure at li57 hours on July 17, and the ~fected

'level channel was restored to normal op~ration.

6.0 Action(s) Taken to Prevent Recurrence Operators have been reminded that a high level of awareness of one unit's activities which could affect systems or components required for operation of the other unit must be maintained.

Maintenance Operating Procedures (MOPs) have been implemented for the installation of stop logs in the CW intake structure.

NRC Form 366A cs.as,

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NRl: FORM 366A U.S. NUCLEAR REGULATORY COMMISSION

' 16-89) APPROVED 0MB NO. 3160-0104 EXPIRES: 4/30/92 ESTIMATED BURDEN PER RESPONSE TO COMPLY WTH THIS LICENSEE EVENT REPORT (LER) INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH IP-530), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555, AND TO THE PAPERWORK REDUCTION PROJECT 13150-0104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20603.

FACILITY NAME 11) DOCKET NUMBER 12)

LER NUMBER 161 PAGE 13)

YEAR ********** SEQUENTIAL -:,:-:-:*:* REVISION

NUMBER :-:-:*:*:* NUMBER Surry Power Station, Unit 1 TEXT (ff mor. _ .. ii ,equired, uu eddhioMI NRC Form 31564 'a/ 117)

Startup checklists will be revised to evaluate installed stop logs which could affect the operability of any Technical Specification required system prior to exceeding the operating mode at which the systems are required.

The temporary modification (TM) process has been revised to ensure that every TM is screened to determine if a safety evaluation is required.

7.0 Similar Events None.

8.0 Manufacturer/Model Number(s)

N/A NRC Form 366A 16-89)

ML18153B857

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