ML20126A603
| ML20126A603 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 01/11/1980 |
| From: | Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | |
| References | |
| NUDOCS 8002150122 | |
| Download: ML20126A603 (2) | |
Text
l PHILADEl.PHIA ELiiCTRIC COMPANY i
Poach Bottom Atomic Power Station bolta, P c n n s y a v:e n t ns j
L13th January Jl, 19s0 Mr.
boyce n.
Grt a r Office of inapuction and Enforecuent Region 1 i
United States Nuclear Regulatory Coumission 631 Park Avenuo King of P r u a r, i a, PA 19406 i
S ti nJ ECT :
R E P O M T A ti L E OCCU R R EN Cli P RO*4 P T NOTIFICATION
'l Con fi rmin g W.
T.
011 rich's conversation with Mr.
- Grounman,
^
' Region 1,
United Stato. Nucicar uegutatory C o wim i a z i o n on January 10, 1960.
R e f o r u n c e :,
Docket No.
50-277 and 50-278 Peach Buttom Unita 2 and 3 Technical Spe ci fi c at i on Reference >:
o.9,2.a(9)
Ruport Nu, 2-50-2/!P Occurrence Date, Janua ry 10, 19 ts o i
Identification of Occurrence:
Misapplication or a hard seated chuck valve in the ADS safety reliof valvo.ir s u p p.l y piping.
Apnaren-Cause of Occurrence:
In a pprop ri a t s design.
Analysis u_f Occurrunce:
]
Leak tostang on the Ais S >afoty-4oisaf va1vu alr uupp1V p161ng identified chuck valves in the pipanu that ornibited through-loakage an tne rov e rs e ( e tt e c k i n g ) direction Each chock valve lholutos an ADS mafety-reliof valvo air operatur and I L., a a m o c i a t, u d str accumulator froni
- t. h e air supply s y s t u as.
The air piping at the con tainment punotration and the piping at the ADS safety-relief valvon 13 designed solAute C l a n :,
l'.
n 'l t h o u g h the tutorsenton pipin, in the dryaoll was not doaigned as s c i a m. l c Cluss 1,
it la all small piping not subjected to large torces during a seismic ovent.
The air s upp ly :.ys t em e x t.e rn a l to thu drywell is not seisale Clu.ss I ti t t.h the lomkage of tne att from tit e accumulators through the hard seated check valve, long term upc4abiltty of the ADS s, n i e t y - r e l i e f valveu cannot ti o aa,surud.
Thi.
- n. a y complicate the couldown of the ruautor in the event. o t' an carthquake. c o u.ti a n e d with a total losa of off-site po.or, The AUS lunction af thouu - valvus during a small break L.O C A whuru tiP C ) 23 i n opu r a b '! c 1.
not affected because they asi used carfy in
- t. h e transient befuse thu Joakage can affect their operability.
3 8002150
l
)
2 Corrective Action:
Unit 2 has baan shut down fo r inspnction or enn p t s. i n c i n a t ele the drywell ro determine acismic class and to replace the h a rit w an t ant check valvas with soft s ea t eil on e s,
fin i t 3 hn* bnen esi n i p p c<l with j
a se.lsmic Class t backup supp.ly external to
- t. h e d rywe l I at the containment penetration to ensure the capeibility o f ADS s a f e t y - r e l i e f' valve operations fo r an e x t e n d ait p e r t oil of time in the event _of u total loss of outside power coupled with an earthqunie.
If the inspection of tin i t 2 reveals.that the intervening air supply system within the drywett is not seismic Class T.
Unit 3 will be shut down to replace the check valves.
Previous Faltures:
None.
Vary truly yours.
}7~J Xgg*X.*.... Lf N.
T.
Uttrich Station Superintendent WTU:lla
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