ML19257C640

LER 79-040/03L-0:on 791203,while Performing Maint on Backwash Line for Svc Water Pump Strainer,Execessive Erosion Noted in Pressure Boundary Piping.Caused by High Water Velocity & Solids Content of Backwash Line

ML19257C640
Person / Time
Site:	Cooper
Issue date:	01/02/1980
From:	Doan P NEBRASKA PUBLIC POWER DISTRICT
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19257C635	List: ML19257C634 ML19257C640
References
LER-79-040-03L, LER-79-40-3L, NUDOCS 8001290529
Download: ML19257C640 (1)

Text

.

NRC FORM h U. S. NUCLE AR REGULATORY COMMISSION f7 77)

LICENSEE EVENT REPORT CONTWL BLOCA. l l l l l  ! l (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATioN) i e l l I o I i l l N lLICENSEE 1 d 3 E l CCODE l P l Rl 1l@l 0 Ol- l 0LICENSE 14 15 l 0 l NuveER0 l 0l -l 0l 0 Ol@l J$ 26 4 l 1LICENdtl 1 lTvPE 1l 1]@lJO di ' A T 2d @

CON'T o ' ,"% !Ll@l0l5 0j0l0l2 9 [ 8 l@l1 l2 l0 [ 3 l 7 l 9 @l 0 l 1l 01 2l 8l 0l@ NO 1 60 b' DOcx E T NLYBE R bd 63 EVENT OATE 74 15 REPCRT CATE EVENT DESCRIPTION AND PROB ABLE CONSEOVENCES h o < [During normal operation, while performing maintenance on the backwash line for the I fo i 3 @ rvice Water pumps strainer, excessive erosion was noted in niping which formed I o a kart of the Servise Water cressure boundarv. The occurrence cav have le3 to opern- 1

[o ition in a degraded m.:de as permitted by (T.S. 3.12.C.2). Had the line failed,the a 16 gtrainer could have been bypassed and the redundant Service Water loop was availablel.

, j, lThis occurrence presented no adverse consequences from the standpoint of public l

, .,, i health and safety. I s > "

Sv5TEY CALSE CauSE COVP VAL %E rCLE COCE CL9 CODE CO"PCNENT CODE SL8 CODE SLBCCCE W l mA l@ W@ l X l@ l P l Il P l El Xl X @ y@ [Z_J @

,, ,, ., ,- 1, .,

' E JL E N TI AL tx ( L N 4t Ntt HErDHT "E V ' DON

• .T<faA 4E'QH T NO CODE TYPE NO l 7l 9l -

l0l4l0l l/l 10l 3! lL l [-j l 0l 4-b N;f' ,_.1A E

i% FuT-il cFFECT JJ AT OCn .

J4 J6 2' 23 ATT AC MY E N T

?>

NPRD4 30 PRIVE Coup 31 JJ COVPONENT

'Am . Ac i W. ON PL ANT YEinco -OuRs .. sysveTTED FORM 3y9 $(PP L s E R YANUFACTURER L1]SLEJ@

- J4 l_;;J@

A 6 zl@ l010 Ji 01 01 40 L2]@

4l l

42

@ lAl@ l44Al 51 11 Ol@ 47

J LSE DESC AiPTICN AND CORaECTIV E ACTIONS lThe cause of the failure is high water velocity and solids coni;ent of the backwash [

i lline which accelerated pipe erosion. The p,ioe is 3 inch schedule 40 which operates I g g lat 50 psig and river temperature. Pipe was replaced. Thewal; thickness of the I i , ibackwash line will be periodically eval.cated to determine whether a change in de- 1 i 4 Isien is warranted. . I 4 1 80 F ACILt Ty UETHOD OF STAfus POWER OTHE R STATM 015COVERY O!SCOV iRY DESCRIPTION 3' '

d @ l 0l 9l 8l@l NA l l Al@l Maintenance Observation l ACTivlT V TENT AE LE ASEC N dELEASE AVOUNT OF ACTtVITY LOCATI IN CF RELE ASE

> e La @ t_zj@i 10 m I i i 4 ) it 44 46 60 PfO' 1NNE L f M P!)$L A E5

'9FR TYPE DESCRIPTION

' 7 4

10 0101@lzl@l" N ao I

PmO,NJ'..ou'iEs D l0 101@l r h l

& m ihPd - @ ff $"* Q

' ! ', [ 2.j@l u

., io ,

ldi.Lj hs[@l i "o'Oc.oP ,,o~ @ 8 0 0129 0 5 ;t 9 NRc u a im 'r , __

m i ll l1l iII Il}

d 3 40 os sa 80. ;

Paul F. Doan 402-825-3811 o NAYE OF PREPARER PHONE $