ML19340B846

LER 80-071/03L-0:on 801009,safety Injection Accumulator 1A Boron Concentration Found Too High.Caused by Stratification of Stagnant Solution.Accumulator Placed in Recirculation W/Unit 2

ML19340B846
Person / Time
Site:	North Anna
Issue date:	11/05/1980
From:	Cartwright W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19340B845	List: ML19340B844 ML19340B846
References
LER-80-071-03L, LER-80-71-3L, NUDOCS 8011120440
Download: ML19340B846 (2)

Text

. . _

o U.S. NUCLEAR REGULATORY COMMISSION e

LICENSEE EVENT REPORT i

CONTROL BLOCK / / / / / / / (1) (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

/0/1/ ./V/A/N/A/S/2/ (2) /0/0/-/0/0/0/0/0/-/0/0/ (3) /4/1/1/1/1 (4) / / / (5) i LICENSEE CODE LICENSE NUMBER LICENSE TYPE CAT

[L/_(6) /0/5/0/0/0/3/3/9/ (7) /1/0/0/9/8/0/ (8) - /1/1/0/5/8/0/ (9, DOCKET NUMBER EVENT DATE REPORT DATE

, EVENT DESCRIPTION AND PROBABLE CONSEQUENCES (10)

/0/2/ / On October 9,1980, with the unit at 49% power, at time 1030, sample analysis /

/0/3/ / of SI accumulator _'A revealed the boron concentration to be 2179 ppm. At time /

/0/4/ / 1520, accumulato r IC boron concentration was found to be 2168 ppm. This is /

i

/0/5/ / contrarv to T.S. 3.5.1 and reportable pursuant to T.S. 6.9.1.9.b. Upon dis- /

/0/6/ / coverv of high boron concentration, each accumulator was returned to within the/

/0/7/

/ limits of the specification within the time required by the action statement, /

/0/8/ / thus the health and safety of the general public were not affected. /

SYSTEM CAUSE CAUSE COMP. VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE P ' i/, /S/F/ (11) /X/ (12) /Z/ (13) /A/C/C/U/M/U/ (14) /_Z/ Z (15) /Z/ (16)

SEQUENTIAL OCCURRENCE REPORT REVISION LER/R0 EVENT YEAR REPORT NO. CODE TYPE NO.

(17) REPORT NUMBER /8/0/ /-/ /0/7/1/. /\/ /0/3/ M /-/~ /0/

ACTION FUTURE EFFECT SHUTDOWN ATTACHMENT NPRD-4 PRIME COMP. COMPONENT TAKEN ACTION ON PLANT METHOD HOURE SUBMITTED FORM SUB. SUPPLIER MANUFACTURER

@ (18) @ (19) /.ZL (20) /Z/ (21) /0/0/0/0/ (22) /Y/ (23) /N/ (24) /N/ (25) /D/1/0/0/ (26)

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS (27)

/1/0/ / The high sample concentration is believed to have been caused by stratification /

/1/1/ / of the stagnant solution in the accumulator. Immediately upon discovery of the/

/1/2/ / high boron concentration in SI Accumulator 1A, it was placed in recirculation /

/1/3/ / with the Unit 2 RWST until boron concentratio'n wn within specification. Later,/

/1/4/ / similar action was performed on Accumulator 1C when found out of Spec. /

FACILITY METHOD OF STATUS  % POWER OTHER STATUS DISCOVERY DISCOVERY DESCRIPTION (32)

/1/5/ (El (28) /0/4/9/ (29) / NA / (30) /_BL B (31) / Routine Sample /

ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY (35) LOCATION OF RELEASE (36)

/1/6/ /Z/ (33) /Z/ (34) / NA / / NA /

PERSONNEL EXPOSURES NUMBER TYPE . _ DESCRIPTION (39)

/1/72 -/0/0/0/ (37) /Z/_ (38) / NA /

j PERSONNEL INJURIES 4

NUMBER DESCRIPTION (41)

/1/8/ /0/0/0/ (40) / NA ,,

/

p LOSS TYPE OF OR DAMAGE TO FACILITY (43)

DESCRIPTION 1 /1/9/ /Z/ (42) / NA /

PUBLICITY-ISSUED DESCRIPTION (45) NRC USE ONLY

/2/0/ /N/ (44) / NA /////////////

NAME OF PREPARER W. R. CARTWRIGHT PHONE (703) 894-5151 l

-8011120""I4 0_

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Virginia Electric and Power Company North Anna Power Station, 'init 2

Attachment:

Page 1 of 1 Docket No. 50-339 Report No. LER 80-071/03L-0 Description of Event On October 9,1980, with the unit at 49% power, at time 1030 sample analysis of SI accumulator 1A revealed the boron concentration to be 2179 ppm. Accumulator 1A was immediately placed in recirculation with the unit 2 RWST which has a known boron concentration between 2000 ppm and 2100 ppm. At time 1345, accumulator IA was determi, u to be within the required specification limits.

At time 1520 accumulator IC was sampled and the boro- .ncentration was found to be 2168 ppm. It was immediately placed on reciteJ!= tion with the RWST and, at time 1640, was found to be within the limits of Technical Specification 3.5.1 which stipulates that the concentration be maintained between 1900 and 2100 ppe.

Probable Consequences of Occurrence Since the boron concentration was brought back within specification in the time required by the action statement, the health and safety of the general public were not affected.

Cause of Event The only source of borated water for the SI accumulators in the past has been the RWST, which contains a known concentration of barated wate- No other sources of makeup or fill have been used for the SI accumulators. The samples obtained from these accumulators contain higher concentration of boron than that contained in the RWST. For this reason, the high sample concentration is believed to have been caused by stratification of stagnant boric acid in the a cumulator.

Immediate Corrective Action The accumulators were recirculated with the RWST until the proper boron concentration was achieved.

Scheduled Corrective Action Technical Services has been requested to develop an analysis to support a wider tolerance band for accumulator boron concentration. a Actions Taken to Prevent Recurrence d It in believed that this is a sampiing stratification problem.

Therefore we have no reason to believe that the bulk accumulator concen-tration was out of spec. No action, other than pursuing a Technical Specification change, is required.

Generic Implications

{

g Stratification of boric acid in stagnant tanks is a generic pre 'em.

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