ML19259C532

Petitions for Formal Hearings Re Plant Shutdown,Mod & Reopening. Generic Problems W/B&W PWRs & Certificate of Svc Encl

ML19259C532
Person / Time
Site:	Rancho Seco
Issue date:	05/15/1979
From:	Christopherson, Reiss J, Vandervelden M FRIENDS OF THE EARTH
To:	Chilk S NRC OFFICE OF THE SECRETARY (SECY)
References
FOIA-79-98 NUDOCS 7906260073
Download: ML19259C532 (16)

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i lHIS DOCUMENT CONTAIN3 May 15 1979 POOR-QUAUTY PAGES e

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Nuclear _ Regulatory Comiscibn y

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7 Wy 1779 order of the cu ~ *cn 7;/ {

Docket Su:Ser 50-312 y'

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Attention:

Mr. Sar.uel J Chilk Secretary of the Corrission I '" '

near Mr. Chi 1E:

We b e e -s p 3iiir Tar. cal-h.-arh regg.rding the shutdown, r:odificatien, and reopep" ifs of M.anc o Seco Nuclea r Generatiivg-stat ien cpe rated by the Sacrarcate l'unicipal Utility ni:;tricq. The 7 May 19 79 Order freg the Corcist.icn to SMUD

t a t e s tha t "... eny pe rson whoDn t e

~-M 4- "? h4 sPfected by this order cay request a hearing with respect co this order." We decand that such hearing be publicly conducted here in Sacrar. ento County, California.

Last Thursday, by 3, to the d i.w.ny o f r % t en:' citizens eseethled for th-: re;ular S3;'JD 3,a r i - M in.:, the SMt:01:src ref aed,to ay.ree to pu1>lic

.e. o '. I '- 1:. Incredible that the public h.aring. un the c:s t : :: c f ree +ning hache has to go to such len.;thu far an een hearing on such a grave area of concern, end that this has to be done at a tien when public a.infider.cc in regulatory bodier,, co-hsions, and publicly elected bom-ds I. at an al.1 t1 ~ icv. Ic would seem that at some Point. the public cust be taken se riove.1) us cicircas, ratcpsycrn, taw ayers, e_nd that the system r.hould not he run for the. benefit of a few special interestr. or financial concerns.

We are aware of the rush that took plac:: to get Three F'ile Islend into co rcercial operation be. fore the end of the 1973 t.xc year.

Ino utility company garnered over $41 million in benefit - ac c reault of what now cppears to be a very prenature start-up of the facility. Uc bcte ir. Sacracu-n to do not vant a " rush j ob" and a pr emature etert-up of our nuclear reactor. We in Sacraa:nto have a public utilit'y and therefore are in a unique positica to work with our public utility, and our public-minded NRC, in an apprainsi of the current situt-lon.

Yet anatingly vc find our:;qlves in the ser.e prediccrent es the tmfortunate citizen:: in Pennsylvarda in their plight with a private corporatten, nane ly, dif ficulty in getting Dt 2 coNSIDEnATIOR and OUE PROCESS, and sirply.

M'!".R7.$ To so?.E VEnY B/. SIC QUESTIG50 !

Af ter naslyzing the NRC Staf f reports, the tran.criptr. of ?mC meetings cnd hearin s, the cc'rrerpondence between SMUD cad the NRC, the SMUD proposal (27 April 2 ?79 lettse f ees Mr. Ysttic e to Mr. E.n old penton, with enclosuree),

and the 7 tray order in quastion hern, ue are very concerned about the delrys in

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reaching ag.ren,ent, che bcsis of that agreenrat and the cubsequeut Ord

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en Str:e1 J. Chilk Ley 15, 1979

>,:co c o the cr iteria for ceperating the tents for FMUD into two li c.ts:"P ror;-tly" e r.d "Long 'Te rn. " Ve are also concerned me the diapsrity between our view of the generic deM n issues end the curions agreer ent between $WD and the NRC staff.

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Fur theimre va believe the citiu.na of the Sacratento area have the right for this pt htic rd rit-w 3nd disetts sion to be held before the ctsrt-up of the Rancho Seco Nuc1ce.r C:cerdt'i.n; '5fstion. ( l'Icase find our ene-ration of generic cc: cerns a z At ta t chun t No. 1, vhich is attached hereto and incorporated herein by this

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tefetunce.)

. I'rtenda of the Earth it a nr.ticeally recognized public inteccst environ-acntal.

2 vi r/nN t ica. M ends of clie Rrth has a long-standing rec.ord of concern over the tmy 1:,3ces gurrounding the developunt of nuclear pwee generation, in -

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partf ular.re have publiched widely on reactor safety cr.d hazards. One interest in the Ordur ir, established by our grave concern for the heslth, anfety, and e temcoic vr 11-h-f ng of our rx.=bers nad others itving in r*:e Sacrn:mato Wiley, who n e r..bject to er:traordimry rick of a t.e rious accidc-mL at Rancho Seco. l'he Or6 r, in our view, inadequately addre.:ses the range of F-.actic safety relr.ted

aciated uith Eabcc.v. and Wilcox reactor cyste:rs, which heve energed p obic=c In the uke of the Three fille Island accident.

N E:r.irce.mntal Cret:ncil of Gaererento (ECOS) is cegrised of 14 u er o: E ai..:a:Icn rith conM ned renbersh3p of cve r 20,000. n: se or.5aniraticus are

.ui dive r:,e.:s the Sacrc: wo Fan Sureau, :'e x o reple.tica G r c.w th, the Lecg te of. h ra Votern, Sacra:wnto Lung Association, and the SccTament.o Ldical Aurillary.

ECOS has e.crively participated in SlCD proceedings for tha past 5 ycarr.. Ecos concerns with reupect to the Order are isc.nes related to c--neric design defic _tencies i n tab e.cz imd k'ilc ox r e c.c t o r r.y c t e cs, and the nqed for due process in anergy 62ciStoa-I.d ing.

'ne DalGIN\\L SMUD " stepayer. k.socist. ion was fotrec in'197I. to ::coitor r.he a c t iv it i es o the Sacra::ence Municipal Utility D is t r.1c t. Two central asneerns related to the order eru, 1) financial and rate icplicatiens of a serious safety reinted accident at Rancho seco which tay be the result of generic dasign de ficicacie.:, and,2) due process with reprd to fell public disclamire.. -..

of potential health, safoty, and econaarc repe.rcusions for mr.bers itving is the viciutty of Enucho Seco Nuclear Generating Station.

He a ra no t ob r.t rue :. Lop is t s, but in fact represent a brend-based sagmt.

of pnopic in the Snemento region that wish to h.ve c hessing. The Sectaranto City Council r.nd the Sac' ne:nto30ard of Supervisors hav.3 pused resoluticas tegt.mtlug iach hearings.

Covernr.2.tal bodies in currounding cotmties' have

. tics voiced concern. Sirtce the refusal of the SFUD scard to hold hearings, sigunturer hwa be:n pcherad a 1 petitions demanding these hearinga be held, it we.:]d be u.we.ticionchie fue you to igacre thia request.

Uo respectfully subuit this petition for ycur cocaideration.

L'c pre:uma the iccues c.re c' Lear and that needed action wil be taken.

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-2 qr s From TNI-2 Acci dent:

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Possible Generic Prob em -

on 4/3 and 4/4/79s Wi th the desi

.g hi ch may

.The ACRS and NRC reviewsdisclosed several pr C A, 8

and control for DC ceneric implications. major items d

'ington

'd operation, suce other PWR's.

have nod possibia a list of thecorroborating The folleviing isf rom the TMI-2 reviews pl us s ou rces..

o the r to Have Excessive n ts :

The S T.N Desion Appearsto F ee cm te r T rans t feedwate l

and cur.iliary an ef fect

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5ensi t ivi ty has or lack of cainof any Pl!R th e B &W

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!!ou c v e r,to the excesssteam generatorscoolant.s e ns i ti v e requirer ex-An primary core the and therefore the plant to more design _ appears to befeeducter flowactiun to E th e keep state on rator Darryl tremes ofcritical opeThe I;RC'S more con t rol.the April ? meeting: '

they occur, d.

under s

C durine once on.B &W pl ants..

..... transients, ts,

re.severeon Hostinghouse pl

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unique-somehow mo lates to the(T r.

are

~'than th(y areand I think that resystem."

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ness of the i seric at p.13) thi nk i t is dca sn' t Al though Ei senhut states:

generic defect, he i t' s mo re (Tr. 4/ 4/ 79 m se nsi ti ve......

think hd "E1's less forgivi ng, "I j ust fecdua ter '

at p.30) ienced '73

'74, D.

SLU plants have exper Rancho (i.e. Oconee'78), butd:. T 1.

the i n the past lfost sients ' 77 Rancho limits being reache seco t

am generatorsa bo th feedWatar bofied both ste Gesse e ve nt showed feet,ater prig:ary hea t si nk,facd J. ;;-:

y".f ' ' ]i; of Q.r. O losi ng the caused a (Ref, and vessel.

31, of a c' d ti o ninjection (HPI

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primary coolantd SMUD s a fe ty cee tino at p.13 anMa tti mo e_t_o s

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of the k

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7.. f I'.25 Var. s i. ri O U.: p t 0-i. i.~.. J r i r i c r. !

oec a us e many o f the ft tors unicn control tnis se nsi ti vi ty a re th e b c s i c vo l u.T.e s, construction and flow rates of the p ri ma ry anc secondary

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1he B6WS P re s s u ri ze r.Ta nr. ( And Fossibly-tha -.

.Q ue n c h T a n k s Tla y d.e Un de rs i ze o.

to Handle Laroe E r.E enss~-

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i In hic.lannary Ic70 momn.

an r' R T T TJ i n <t a r t n,-

., nar.ed Cresswell documented his concern about generic problems wi th BLU plants.

As part cf his memo, he raised the following concern:

"Beca use of press uri zer level cai nten-a nce problems, the sizing of the ressu req ui re f ur the r review."

p(memo ri ze r may l'8/79,

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Cresswell to Streeter, P-2) lie s i tes as e vi de nce of this problem, (1) the fact that p res s u ri ze r level vent of fscale fo r approximately 5 minutes during t h e f.' o v. 29, 1977 Davis-Sesse loss of of fsi te power e vent and (2) tha t loss of fe e dwa te r at 100% power wi th the reactor cool an t pumns running the p res s uri zer Uq

.g., M rev vo i d c c..ip i a t s i v.

7.- the T"!-? a c ci de n t. the

?m r 'I:- s s u r i Ic r i c-n '

'i :.d i c a :i o r.

.:3r c'# scale fr core

_. e n 7 mi n u te s, whi cr. acy be dus to sizing,or bl e tas _s u ch as l e v e l....i n s t r una n ta ti.o n cies i gn. _.

.o th e r p.roEl e' i ndi c& t i on s a ppa re n tly, The offsc v i ol a'te th.e.

r'e g u l a ti 0n s 'a n d 9 0i de s in 10 CFR 50; Appandix T - -

C ri te ri a 13, and Reg. Gui de 1.97. '

_3.

P res s uri ze r Level Indications May B e Mi s l e a di n g.t o_

t he Ope ra tors :

The opera to r of TMI-2 a ppe a rs to have i n t'e r p re t e d '

the ri s i ng p re s s uri ze r level signal e a rly in the accident as a sign that the reactor was re turning to a s ta bili ze d con di ti on.

Perceiving that the signal was telling him the press uri ze r was about to o verfill, and being aindful of the recent PWR i

experiences wi th ove rp ras suri za tion caused by a

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" solid" press urize r wi th puras t ry i n g to feed in liquics, the ope ra to r f c 1 ; r.:c d what would be good practice and shu: cff ont of th: high pr2ssure e

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POS S I BL E _ CO0t. AN T S T AT US D U R I N G T H I - 2 A C C I D E li_T,.

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S t e t ra gene ra tors 7

shown cut-away t-1; AC expose press.orit and OTSG heat ed-

%:e te r tubes.

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" /. s the fio.. VSi,-i ty i n th s RCS.till

,1 remain normal. cbout 25 f t/ sec, s tea m wa ter separation will tend 'no t t0 cccur.

Some lic.i t'ed s team a ccumul a ti on cay. occur in the upper hea d of the reactor vessel i n tha t s p e ci fi c l'oc a ti on o f the Rts, asvel oci ty i s low. "

(Cresswell to S treeter.

1/8/79, Enc. 3,

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Eecause th ey' h a d n o t calculited 'any f uel f a i l~-

ure, they ha d no t considerad Hg gas might.also collect in the ves sel' hea d.

S i mil a rly, their a s s ump ti on that the coolant pumps c on ti nue to ope ra te did not allow for steam voids collectinn

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.at the hydra uli c hi gh points of the s ys tem and ultimately leading to pump c a vi t a ti on'/vi b rati on and neces si ta ting thei r shutdown.

At TMI-2. the pucps we re shut down due to vibration in an attempt to save them from more serious dana ge which might render them to tally un a va l l a bl e.

This may ha ve been the correct action for a fille d p ri ma ry loop, but the large voids in the TMI-2 pri mary ic op appear to have prevented natural convection cooling.

The prosonce and e r. t e n t of these vo i ds an d s t' am buco!es ieare la rcely unic _.- t L l c by t.T 0 0c ra 50r5.

The e f fe.ct of turning of f ali reactor coola.nt f

. Pumps d u ri n g, a. t ra n s.i e n t..may even_ occur with2.ut 77~ 4 the. ope ra tors a ction.

I,f all o f f.s i t e p ow e r i.'s lost, th e four S000 hp coolant pumps will be chut down (es will the make-up and main feedwater' In light of the TMI-2 accident sequence, the loss of all reactor coolant pumps during a t ra nsi en t where p ri :na ry system voids are present, is a generi c concern. for all B 5W pl ants.

5.

A c t'i d e n t Consequence Mi ti ga tion is Cn mpl i c a t e d-by Plant oesign:

The RHR heat excha nger has not been put into a c ti on at TMI-2 becaise (1) it recuires the hi ohly ra di oa cti ve ccolant be ci rc ula ted outside the containment and (2) the concern that deb ri s in the cool t.nt woul d cl o g t i. c R M P. heat e x ch a nge r.

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b Both of these condi ti on s a re lil.ely to be nvo l vi ng si:bs tan tial i

present i n any.a cci de n t fuel f ailure or melting isnd should nave been a'.desien c o n s i de ra'ti on..

A s i c:ila.r p robl em e xi s ts wi th th e hyd'ro. gen

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re c o c.b i n e rs.

These systems are also loca ted o uts i de-the containment and, once co n tami na ted ui +.h.ti. con ta i ome n t ra di o a c t i vi,ty, wi ll create l9 c o ri ous.Jna i nten ance a nd s u r vei lla nce p ro b l'e ns~.

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At THI-2, tons of lead b ri cks h a d t o b e b ro tigh t "

in to buil d a shield fo r these sys tems. M

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A third system design problem involves the steso

gene ra to rs whi ch vent to the a tmos phe re.

There ?

has been a chronic probl em with leaks in PWR s team gene ra tors.

( Re f.

h' U R E G- 0 410, Rev.

1, May

• 78, Tasks A-3, A-4 and A-5).

When the p ri ma ry loop is contami na ted with ra di oa c ti ve me te rial, s team genera tor leaks allow the ra di a tion and radioactivc gases to be t ra ns ferre d to t h.e s e c o n d a ry a n d e v e n t u a l l y ve n t e d t o the atmosphere.

ilhen Ste am Gene ra tor B a t TMI-2 began leaking, it was i solated and the cool a nt pumps sh ut down.

This left only on e s te a m --ge pa ra to r a s a p ri na ry heat sink.

One c a n'- co n j e c t'u re' a b o u t the p robl ems t 5. a t would hcve bee n c r e a te d i t S t ea m Ge ne ra ter A aise had or ceveloped l e a i:..

MI.5 *-

In ger.aral, it cppears many systens for use in' normal as.well as accident situations ha ve been

..d.e s.i g n e.d w i t h i n s u f_f i c;i.e n't:.c on s i,d e ra ti o'n of accident co ndi ti c'n s' i n vol vi n g 'l a rgs amou n ts of'

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ra dioac ti ve con tnmina ti on. -

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~i I mol ica ti on e.

f o r _ P.a n c h o S e co e nd Othe r 1.M y c,ci. dent _

g. g75 Th e re a re._.-10 B Lh' rea c tors in the U.S.,

one of which is pf_rma n e n tl y s h u t dow.

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l hTt i c d e s i o n o f the B&W portion of these pl a n ts h a 's been s ta ndardize d and mos t have a nominal 800-900 Elle ra tin g (Indian Point is a major exception).

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' As. a res ul t of s tan ca rdi fa ti on., the me jor com.conen ts o f the Nuclear Steam Supply Sys tem are be sically the same,.

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for TMI cnd Ran cho Sa cc.

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Se vera l impo rta n t s imila ri ti es - be tween P.ancho S eco e,nd

. TMI-2 are i,mp o r t e n t. t o.. n o,t e :

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Steam Generator Desian: -

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BaW plants a re the only PWR's to use the once-through s teca 'ge ne ra tor de:ign.

While the design has technical adva n ta ges in providi ng s uperheet in the go ne ra ted s te am, they appear to be vu,lnerable to bcdling dry or over-cooling the re a c to r coolant unde,r certain feedwater 19 7 8.), Ra n cho S e co,. "li gh t condi ti ons ( fo r e,x a mp l e,

re fer to (d bulb i nci de n t" of Ma r. 29.

OB.. Reac tor _ Ves sel Coolant Level:

i The PWR relies on the fe ct tha t the entire primary loop is no rma lly pa i ntaine d full o f wa te r and a t a pressure hi gh enough to precluds boiling.

LTh e o n e area where a void is mai n ta i ne d is in th e p res s uri 2 e r.

By hea ti ng or sp raying the s teem bubble in the pres suri zer the r esrure is cor t rl' e e wi th a noninal fluctuation in the W6 te r level within che pressurizer _ tank.

This p-uater.leval c2asurecen: is relied apen as an i ndica ter of need to add water..

IM gh Pressu re injection. (. PI)

S is a utoma ti cally turned. on for low coolan.t pressure,' -

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There is no di rect mea surement.of the wa ter' level in the reac tor vessel at TMI-2 or Rancho Seco.

I ns te a d, the level must be inferred f rom the me a s ureine n ts o f inle t' Ys exit tempera tures,. cool an t pres s ure. Vnd flow condi-ti ons.

As shown at THI-2, these condi tions may be C '

i nadequate or misleading i n di ca ti on s to the operator of the reactor coolant l e vel during the time a transient is o cc u rri n g.

This is a s e ri o u s de fi ci e n cy.

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P res suri ze r I,e vel P.e a s u r eme n t :

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III of this report. th e re As men;i oned. in Secti on ability of the pressurizer about the accura te rea dings durinc.

is a c:ncern It is' level instrument to provide a blowdow'n and/or rea ctor cool ant transient.

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pi. pi n g not cl c a r i f the ins trume'n'ts a nd i ns trument those arrangcments a t Rancho Seco are the same as shoul d be.i nves ti ga ted,

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y at IMI-2.

This:

. an'd Sa f e tv Svi ems _:

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Se ca ra ti on of Con trol sancho Seco in March of 1978 at The light bulb event of non-nuclear (and non-control equipnent on thd^

vividly showed the impa c t S a fe ty ) i ns trumen ta ti on and d safety opera tor knowl edge of plan t condi tions analso showed how the a cci de nt f u nc ti on s.

The TMI-2 improperly isol a ted s ump pumpsa fe loca tion mal function of an from a trans fe r radioactive ma teri al nor to an unsafe area (e.g.,

con tai nmen t) can Ra ncho ve n til a ti on sys tem).

inside the (e.g.,

the a uxilia ry buildi ng and is ola ti on signal to the pump low reac tor pressure to have an Seco appea rs pump valves whi ch is ac ti va ted onp res sure condi tions.

v or high co n ta i nme n t such as non-are apparently other areasand power supplies whe HowcVer, there o f :. f : 27 n d n

-siftty G nctions can i n s t r ume n ta ti on nucicar i r. :.c r. e c e n c e.c 4 s

y sa ety in 3,g p l a n t e.,

r

c e.:.r o--i s e Actions i n Fi rs t 10 Minutes of-

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C E.

Sa f e ty-Rel a ted Opera to r

.._y..,..._

~~

'a' i ra n s i e n t :

deci s ion.

to make some cri tical

...<2-th e fi rs t' 10 mi n u t e s o f TMI-2 had The ope rators at on s a fe ty-rela ted a c tion s wi thi 6they had to decide whether For i nsta nce,

reactor or s o f ove r-p res s uri zi ng thethe pressuri ze r wen the acci dent.

" solid" to take a chance This operator decision off the HPI pumps when

. turn minutes i nto the accident.

and regula tory implia at 4 operational, considerable stress.

There invol ve d techni cal, period ofoperators eithe E believed or during a ca ti o ns d

disre ga rded some perti nent i ndica tions of the magnitu is evidence th a t the action i n maki ng thei r decisions. Such anthe "i ncreduli ty of the trouble and is re fe rred to as is predictablein WASH-1400 where they s ta te :

response'-

E b

w

~ ~r-e

9

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ollnting a LOCA, hurian reliability would.

"r

'be. low, not o nl y b'e c a u s e o f t h e s t re s s i.,vo'i ve d, but a l s o b e c a us e o f a probe bl ei

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i ncre dul i ty respon s c.

Amons. the ' opera ting personnel the probability o f occurrence of-la rge L OCA i s ' bel'i e ve d to be low to t h a,t,

a.for some. moments, a potential response would likely be to di s beli c've pa nel i ndi c a ti.ons.

~-

3 Under such conditions' it is estinated tha t t no action a t all mi gh t be taken for at least one minute and that if any action is taken ld likely be ina ppropria te.

it Wi.

.-e ga rd to the performance curve, in error ra te was assessed the study the gene {al 5 minutes af ter a larce

-1))after to be 0.9 (9 x 10-30 mi nutes, and to LOCA, to 0 1 (10 0.01 (10 I) a f te r, s e ve ra l h o u rs.

It i s es ti meted that by 7 days after a large LOCA, there would be a complete re cove ry 'to a ne raal, s tea dy-s ta te condition and tha t normal error ra tes fo r individual beha vi o r woul d apply. "

(UASH-1400 Appx. III, page 61)

The new req ui re me n ts in the NRC Bulletin is sued to Rancho Seco and othe r St.W plan ts requires the operator

n.- F v. cl ue decirir-s re g a rdi r.g the v3'idi ty of sreistrizer icvel readings,.; h i c ". ccuid 4cricusly rig a c t tne ccurse of a trcnsient cr accident.

(Sea IE Bulletins 79-05 and 05A.)

~

practice is to h u t'o'ma te a ny s a f'e ty a c t i on G'ood design reg tiire-d-\\'1Tirim tTie'~ii rs t fD mi nb te s o f a n a c'ci de r.t.

R a n c h o.. / _.j -

~

This is Trcferred to as the "10-tiinute Rule."

rule

~

Seco ope ra to rs may b e_ req _ui red to violate this

'I to compentate for possible design inadequacies.

O F.

O t h e r c o n c_e_r_n_s.:

There are additional issues to be reviewed on Rancho Seco as a resul t of the Tlil-2 experience, which are listed here for further c on s i de ra ti on -

1.

Pos t-acci de nt mo n i to ri n g i n s trumente ti o n does not

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appear to be a deq ua te.

2 Marning and evacuation plans need improveatnt.

a iI I

r E

's I

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[

(k d h dh

%[$"h,5.UM1.$Qga{QQggi).7,gg,g;t fg]'(j;[.epd-Q 3

j e

10

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3.

Gold-up tanh sizes ~for ra dioa tive gases may need to be increased.

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r'o o m radia tion. le vsls and possible contemi.

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}'-

4..

Contiol

.:. f

.~ ~ ne'.fon may be excessive during an accident.

5.

Steam genera tor vol um6 may be too small. -

6.

Ana lyses,o'f., small 1,0C A wi th. gompl ic a ti ng f a ctors -

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needs to be reviewed.

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7 Ability to handle d6bris i n p rima ry loop is que s ti on abl e '

I 8.

Follow-up of ACRS letter on possible g e n e.r i c problems discovered in TMI-2 experience-

~~

O.C.o n,c l u s..i.o._n s :

.- -.-.,..,~--

g

.e.m The details of TMI-2 have not all been determined or eleased at thi s wri ting.

However, based on the preliaina ry in forma-tion availa ble, there is suf ficient evidence of possible generic p roblems that other B&W plants such as F.ancho Seco should be shut dcwn nrO as a minimum run at ' lower power (a nd th us lower decay heat to contend wi th i n an accident condi ti or).

s e

e i

n i

E t

he 4

6

..m k

1 e

2 I m

8%*

h

-.. GF.tiEIC PEOSLEMS W.L:~;.' W-.

}

M '.

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to have a re probl ems observed a t..TUI-2 whi ch' appea r s

.eview generi.c s i gni fi.ce nce ar.d requi re con s i de ra ti on and These

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on Rancho Seco.

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to ha ve excessive sc2sitivity

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The B/W design appears O

1.

o f, f e e dw a te r trans i e n ts.

to loss

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s te am gene'ra to r, vesset and pl'umbing O

2.

P res s uri ze r, c re a tes probl ens.wi th bubbl e f9'rma ti on i n J

arrangement hydraulic hi gh points.

once-th rough-s te ar.-ge ne rato r (orsa) i cvel for other appears to be pore ' complex than O

3.

e r,w ' s meas ureme n t designs (it u s e s i rWe n to ry b a l a n c e rather than direct r

T measurement).

'ComEon-mode f ail ure pos sibili ties in fee dwa ter,sys tem and auxiliary feedwa te r sy s tems.

2, twwc.p '

G A.

have been BMl's pres surizer tank and quenc,h tank si:es G

5.

Ao questioned.

be sensitive arrangement a ppears to 6.

B T.W ' s p ri m a ry l o o p s team bubblp fo r;n tion and pump CaYi-to s team bindi ng, m,~+

w g

tation.

level are tx &pressuri ze r level /ves sel Operator data on during an accident.

s O

7.

unroliable and can Le nisleading e xi s ti ng or resulting s tea n ge ne ra to r l e a;. p ce vi a us :yreq ui re d s team gene ra "B"

i s ol a ti o r O

a.

fror: the transient and complicated he ndFing o f the transient ( ge n e ri c ' PWil

/*' '

problem).

accident was coriiplica ted by loss of (turning o f

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can also_ be caused by loss of al O

9.

The TMI-2 This all coolant pumps.

oC of fsi te power, can and do sometimes stick open ecusing i J e: -

e Relief valves small LOCA coinditiori.

(Generic problem)

O 10.

i ns trumenta ti on a nd da ta for post-TMI-2 had. i ns uf ficien t to be in non-compliance

@ 11.

accident moni toring and appenrs(Pos t-Accident Manitoring).

1.97 wi th.Ru gul a to ry Gui de is a violction of

@ 12.

Offscale readings on level i ns truments General Desi gn Cri te ria 13.

unshielded and this creates a O 13.

Hydrogen re combi ne rs a re o p e ra ti on. fw' problem in pos t-acci de nt i) s.

f k

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