ML19259D391

LER 79-032/03L-0:on 790914,leaks Discovered in Both Containment Spray Sys.Caused by Corrosion Accelerated by Galvanic Action.Matl Change in Nipple Recommended

ML19259D391
Person / Time
Site:	Oyster Creek
Issue date:	10/10/1979
From:	Ross D JERSEY CENTRAL POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19259D385	List: ML19259D384 ML19259D391
References
LER-79-032-03L, LER-79-32-3L, NUDOCS 7910180419
Download: ML19259D391 (3)

Text

CONTROL BLOCK: l l l l } l l (PLE ASE PRINT oR TYPE ALL REQUIRED INFORMATION) ,

1 6 M lSN9 l J l0 lC lP l 1 l@l 14 0

15

l. j - l 0 l 0 ] 0 l 0 l 0 l - l 0 l 0 ]@l 4 l 1 l 1 l1 l 1 l@l57 OAT LICENSE NUMBER 25 26 LICENSE TYPE 30 l lQ 58 LICEN5EE CODE CON T 011 ", "[

5 e l L l@l 01 5 l 010 l 0 l 2 } l l 9 )@l 019 A9 l 114171974 }@l1 EVENT DATg 75 l01i j0 l 7 l 980l@

REPORT DATE 8 60 61 DOCKET NUMBER 68

' ,

_. _

EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h O 2 I Durinq normal operation, a worker discovered a leak in the area of the I o 3 1 (1-3) ' containment spray heat exchanger. Investigation reveased that a 3/4" l 0 4 I nipple connected between the water box and the relief valve on the service l o 5 l water side was leaking. Additionally, slight leaks were discovered at' l

!o le l the point where the AP transmitter instrument lines tap off the ESV l lo17 I outlet pipe on the (1-1) and (1-4) heat exchangers. Safety significance j io 3 l is considered minimal since the exchangers were not inoperable. l 7 ep SYSTE M CAUSE CAUSE COYS. VALVE CODE CODE SUBCCDE COMSONENT CODE SUBCCCE SUBCODE 7

O!9 8

l SI B l h lE h lDlh 9 10 11 12 13 HITlElXIClHlh lGlh lZlh 18 le 20 OCCURRENCE REPORT REVISION SE QUENTI AL EVENT YEA R REPORT NO. CODE TYPE NO.

LE R/Ro O , reg 17 19 l-l 1013 { 2 l l/l lo 13 I ILi I-l (01

_ 21 22 23 24 26 27 28 M 30 31 32 AKEN A ON ON PLANT M HOURS S8 i FOR 6. SU PLI - MANUFA UAER lJJA l @34! X l h

.

l35 Z l@ lZl@ 36 lo l 0 l 0 l 0l 37 ' r) lY h lY Ih 41 42

[3Zjh lZl9l9l9l 4 44 4)

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS i iO l Analysis of a failed nipple from a similar event revealed that the leaks l 3 3 I were caused by corrosion accelerated by galsanic action. The previous i analysis also recommended replacernent with stainless steel nipples. In  ;

, 7 l

,,3 l addition to repairing the leaks with new nipples, the relief valve l 3 , l nipples on the (1-1), (1-2) and (1-4) exchangers were replaced. l 8 9 80

% POWER OTH ER STATUS DlS O RY D'SCOVERY DESCRIPTION STA ~

1 5 l E j@ l 0 l 9 l8 l@l NA l l A l@l Worke 's observation. l ACTIVITY CO TENT AMOUNT OF ACTIVITY LOC ATION OF RELEASE RELEASED OF RELE ASE NA 1 6 8 9 l Zl h l 2 lhl 10 11 NA A4 l l 45 go l

PERSONNEL EXPOSURES NUMBE R TYPE DESCRIPTION 1 7

• l0l0l0l@lZ!hl

NA l PE RSONNE L INJURIES NUMBER DESCRIPTION 1 s l 0 l 0 l 0 j@l NA go l

8 9 11 17

,r LOSS OF OR DAMAGE To F ACILITY lI ,I TvPE DESCRIPTION NA I J 1 9 lZjgl l 8 9 10 7 9} Q18Q y go 15 E D CRIPTION 2 n 3 9 l hl 10 Veekly news release - October 16. 1979. l 68 69 llIIllllll l1l 60

"

• NAf/E OF PREPARER _

.

1

-- - Jersey Central Power & Light Company f; [f.- ; . (f g ]

.

M U "- --

Madison Avenue at Punch Bowl Road Morristown, New Jersey 07960 (201)455-8200 OYSTER CREEK NUCLEAR GENERATING STATION Forked River, New Jersey 08731 Licensee Event Report

.

Reportable Occurrence No. 50-219/79-32/3L-0 Report Date October 10, 1979 Occurrence Date September 14, 1979 Identification of Occurrence During the normal working da- it was observed that both containment spray systems had developed small fpe leaks. This event is considered to be a reportable occurrence as deiined in the Technical Specifications, paragraph 6.9.2.b.2.

Conditions Prior to Occurrence The plant was operating at steady state power.

Power: Reactor,1889.8 MWt Generator, 638 MWe Flow: Feedwater, 7 07 x 106 lb/hr Recirculation, 15.2 x 104 gpm Stack Gas: 3.85 x 104 pci/sec Description of Occurrence On Friday, September 14, 1979, at approximately 11: 30 a.m., a worker in the area of the (1-3) containment spray heat exchanger noticed water leaking.

An investigation revealed that a 3/4" carbon steel threaded nipple connected between the water box and the relief valve on the service water side was leaking. Additionally, a slight leak was noticed at the point wnere the AP transmitter instrument line taps off the (1-1) containment spray heat exchanger emergency service water outlet pipe. At approximately 2:30 p.m., there was a similar leak discovered on the (1-4) containment spray heat exchanger at the point where the AP transmitter instrument line taps off the ESV outlet pipe.

7 r1 11 , a s Jersey Certral Power & Light Company is a Member of the General Pubhc Utihties System

.

~

Reportable Occurrence No. 50-219/79-32/3L-0 Page 2 October 10, 1979 Apparent Cause of Occurrence All three of the leaks were caused by corrosion accelerated by galvanic action between 90/10 CuNi and SA106 Grade B carbon steel.

Analysis of Occurrence The containment spray cooling system consists of two independent cooling loops, each capable of removing fission product decay heat from the primary containment. The safety significance of this eve.1t is to be considered minimal since the containment spray systems were not inoperable. The leaks discovered would not prevent the equipment from performing its design function.

Corrective Action Since this was not the first time this type of incident has occurred, analysis from a previous nipple failure resulted with a recommendation to change material selection for replacement nipples to 90/10 CuNi or stainless steel.

In addition to repairing the three leaks with stainless steel nipples, the relief valve nipples on (1-1), (1-2), and (1-4) containment spray heat exchangers were changed on September 14, 1979, to stainless steel as a preventive measure.

The AP transmitter instrument line nipples on (1-2) and (1-3) containment spray heat exchangers have been changed to stainles.s steel with approval from Generation Engineering. Also, an engineering request has been submitted to examine all lines connected to the containment spray heat exchangers to study material compatibility and make appropriate recommendations for a permanent solution.

Failure Data Similar Events: RO No. 50-219/79-04/3L-0 R0 No. 50-219/79-22/3L-O

,

_'_

-

j i i i -