ML19220C941

Handouts from 790405 Briefing

ML19220C941
Person / Time
Site:	Crane
Issue date:	04/05/1979
From:	Levine S NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES)
To:	NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES)
References
NUDOCS 7905160083
Download: ML19220C941 (10)

Text

{{#Wiki_filter:- 50-320 Handoutsat brieri"9 00 spril 5' 1979 given by saul Levine 118 154 7 90sie oog3 o i

S

• es.

== o** g (, +; 5 I I.'% m -} s ~ ,) n s. t M N k _e py NN kk s N( s j bq e w O, m 1 g>t Q, R" R. g I 8 k. -g w 4e' 'd 118 155

THREE MILE ISLAND 2 PARTIAL SEQUENCE OF EVENTS Backcround This sequence of events is based on information av"' ,e in the Field Ccimunicaticn N;tes at the ICE incident center, draft c.aterial prepared by Region V & communications with NRR staff at TMI. 1. Sometime between 3 and 4 am, Wednesday, March 28, 1979, while cperating at 95% power, a problem occurred in the feedwater polishing system (full ficw condensate dcmineralizers to remova condensate impurities to preclude their entry into 5/G) causing all S/G feedwater pumps to trip. > i 2. The loss of feedsater flow to the S/G caused a turbine trip. (Steam flow / feed flow mismatch). Turbine bypass valves opened to dump steam to condenser (automatic action). 3. The transients on the primary system caused by inadequate S.G. cooling resulted in RCS pressures in excess of RCP trip pressure (2355 psig) and reactor trip.- 4. The RCS pressure increased to the'setpoint of the pcwer operated relief valve which opened at 2255 psig pressurizer the code safety )\\0 t

): relief valve cpened at 2435 psig at approximately.2 min. The pressurizer began relieving steam at this time to the Reactor Ccolant Drain tank inside containment. 5. The rupture diaphragm to the Reactor Coolant Crain tank ruptured due to continued steam ficw through the pressurizer safety relief valve. 6. Contair. ment pressure increased due to venting through the ruptured diaphragm in the reactor ccoiant drain tank. the power c;erated re!ief valve is designed to close at 2230. It s. appears tnat the code safety re!ief vaive On the p essurizer stuck cpen during the transient. 8. When the RCS pressure dropped so approximately 1600 psig, HPCI injection was automatically initiated. The trace of pressurizer pressing indicates that this occurred at between 2-2.5 minutes. The pressurizer level was observed to be increasing. 9. On response to the less of level in the pressurizer during the transient the operator tripped the RC pumps. This is required because of NPSH concerns. 118 157

91v 10. Betwein six and eight minutes into the transient the level in the pressurizer indicated'the system was coing eclid. The Operator reset the SI signal, halted HPCI infectio 1. 11. To turn of the HPCI pumps, its necessary to reset the SI signal and clear the ccntainment isolation. Tnis resulted in the aut: 2 tic pumping of RCS water frca the reacter ccciant drain tank to the Auxiliary Bldg. This water was pumped to the rector bleed holdup tanks (Radwaste storage tanks). 12. Cue to thic c: tion, the pressurizer le.el dropped and at approximately 10 minutes HPCI was restarted. Once HPCI was restored, the operator maintained level in the pressurizer 13. with HPSI flow. It is assumed the code SRV was stuck open during this period. Folicsing HPC'I Restart Operators maintained pressure in R:S w/HPCI ficw and adjustments to A. Appears difficult to maintain (info not clear). PZR level PORV. with code safety vahe apparently stuck. Sometica af ter 1030, stuck valve apparently reseated allcaing plant B. to increase pressure to 2000 psi and maintain PZR level. 118 158

): -4 C. In early ef ternoon operators tried to reduce pressure to permit normal decay heat remtval. Problems th high radiation level, pumping of high levels to Aux. Bldg. o!.)er precluded this. D. At approximately 7:03 pm the operators to 22:0 psig in an attempt to collapse any btbble. At 7:53 pm the 1A reactor coolant pt p was restarted. 1. Auxiliary feedsater was ret available early c.. b l dl :nv.i u:kt m w .a.._.-. ru...a s 2. When Aux feedsater did start apparently cold water as pumped to dry S.G. 2csult was tube dansge particularly in S.G. 5 which was isolated. (tLbe failures assured in view of rad levels) I 8 J/

4 a s /f i STEAR i i GENER ATOR i s_L STEA5 N 4 4 I I CEHERATOR i \\ fi t i i 8 8 /~ ,l ) i,= ,7 8 I i REACICR - i c: l' / I" l l M ' -2; A-j* v i 3 7_E~j j h l i I T , 'E b i }. j;D 8'-0" ) d r, " i j k __ i

2' 3 7

. ANT 4, [ l 4 i l (( t F L + 1' j ..t _d.u \\y. k Jl g s 3 ' n!t-S MN., I f 31'-C" E'a ' -0 " i g 81 [ i 29'-3 5 i I g i j 1 4 7 \\ l i 9 f \\ i %/ I 5'-0" i_- f 3 Q 9'-0" tc}~T -- / p p g-,q-118 160 REACTCR CCCLANT SYSTEM ARRAS 0 M -e u, - 'c r. x 0 r a;c*.L.r. 5-m.C:4 f.'2;T I

.1 t' l" /~ ' ' ' '" ' ' " ' " ' " REntTcR PRE 550RlIER ] Q r COCLANT \\ 8 / PUwP P Q,, s. e/-(G A._ -m@j r- ~I i M .~09 i =.7.. p I( I \\ ,/

U mG my-7 j v y a

::a t

3/ 's Sj(g'h [-0 4W y ,<\\ /

c -7 a

,' / .i I/D M" e n d.1aw ~ r ..e,,r a a 1 q t %l i N ai- ,,u -- 8~ J4 ~

• 11' - 10 ;

2s- %, if'-6j} ~ / 118 161 REACTCR CCCLA. " 5YSTEM ARP.ANGEMENT - PLAN Til: E E LC LI 'S' C " 't ' " \\} ';T.' T'.C:-i 'O. I 2

A, e -a e M ess Mh 3., p..N ~ ..e ~ - - o 5 A ,3 a ~ = = - s T- _: =r n ) ( - - ~. = e._ s O. o - ( ~ _= o - ~ g~~ ~ o.. a - - e ann P J~ .d 87. M ~ L 'L ci "8 2-- d., 5 w1 ed %ed ea= n. ~o O =9 .I } = ,, a

3. \\

n a >, = 5 N v u ,e. C3 n I f M j gx h ,1 = h, 2 ~. m. ~o

o; I

u

- u. x i 4 .J J. / a 66 '= de

/

E*; = w .o = N he. O, .e f=. 8'9 g t . ~n A. o-h._ o m o/ Lh = o ~ -- M C M g a n., m. nn a a s e D r, m-ss = oO =, ~ a a. a LA.W.S =,, 3 C) 6md n o s ~

,

= uu a =- o--

== s. n o o~a gg u ga s _ _ _ _ _ = _ _ = --- --- ) \\ N J 't ,f ,?a.- ~.- i n / 7) o ,-.z n c. as }4l0 Um ^ ~ a i REACTOR COOLANT SYSTEM FLCW DIAGRAM AT FULL PCwER STEADY STATE CCNDITICS ~ m u.a a s,,n mmr.n.=, e- :

'h'

• ?l-0 kW
• jA&k

., ? W3CWIDM [MLMM3.iXi'.? Ii;d.mGs hs.'.. :L...BRMM!L2 MZNiD : d= bh T +,oJ.- W:.:. L.L:%a:-. .W. a.2' t :G 1.M en.s.L.1:..,au ?Y. A q =v'.'.~ y y :y; f < 3. r' ~.,'m- ~~ ' ~~~w 7 'g.5'"~~ c :cK; 7.~,g '- "--- d N * * '- @' D..?,',l_ '...'rf,;',,".Q, ,'g;^. /W pM.'./1 Q f /JMr""*** \\r" %( W.:1..; m. 2 : 5 1.h. saw ; - '^ Rad:C.1C:ks.s team 5 % :. w. :. i, g M r s. V. y - ,f' ;. s ~f 'I' Radiation under dome ( .,,) nr- = w m y t.,fl/ ' "- y:.S 'f. %.L s-

1. l ;}

V:

\\ \\4*Q u p.c wmy?s., r

%.; y

'.,::p-. _. ". r-m m.u..w^% W G.h-m G \\ R,J.5'nx :~c....",W.m ). n A x y'}g &l2, ~. -o.-, _y - \\ 'T;:W.%k, I & ~ \\ f,/'- l ' ': ' ^ ^ ' ~ K .'" ~.

'*-*%* y-C' Y

- h .7 ?I' 7 NORET - , \\ [h h . / Q./ 7 GHIELDS (/ -@ T q--Q,,@ye. Ct9,,... m s' , W--w. j 2'4 ; e pr***=. W.. m. ". *\\hw q ' f-{/ . j,.- l t ,,,,Ja% q

., S;, " *7 :fQ? ',

U i}l N W-6: 7 N i*' Q w A., : K. - i. i r *, - -- s p,, -C,,_ -~7 g ,.1 ~ k Nf Y I Y!,,e, ' ' \\ b A W \\ t Y d ,: !N ' ^ f Q = n) {m> *( nf,lr-H. ! b. 1l l, >s % v N:lfp/ ph'9rii 5.:- y: Y VV/ ,b 4 r 4:x ' < * .,q \\\\ \\;

• ?

  };

L <'y., % ~'-i \\ ~ / p. K.- Uv })CdNTEOL- ' ,CPR E SS U P!Z ER 'j f "1., - ( *%:e.Yf'./ 1 p j /. '- ',^g//'/ - ['. D* ') G '". l-1.C," If .t' ' C N F E3CTCR. /(PCCS' 1, /' "'% ! /[ L' 4 - i CCOL\\NT -- U -* 1 - D I I-O r* L<, / *6 it ,r. .y / T U P W. - . * - f s g i- %* y Yv,,.-.l 4 S -.. - 'i, s a s y 4 G E N E R AT O % g***^'$. f v/2 JL-J t% -\\\\ (. .. 1 - !%m_ t e I z PIPE p' 5 ./ / .f f' y pus.4p M 1[ 0

• a! [/

f ' C,, M/ - .. ELCAO!NG

• (,,,,

I-1 ^ -n  ! f f ' ~,,- A ?"A %^ ye-l i i y jlt l h,, "2 '- # /DQ [,/ / [ j[' / ~ k^ )9 i,,r$, 1 *(p "~d @i '/ \\?*[. G ]t w a !!j3, %D UN .! I

• 4 "T

I,'_. ' ' s ]o '*' [, *;. ~- E?JERGENCY I?y. jfN 7g io !e,, % g--< .~ -

• l t

6 . A *Q, A U1CH-

• *c-[ ' -..' y M
• t'.".i s 'n 0
• PHE 3 SUPE - - A O -I* sy

' n. b .~,4'. j / /' ,4 4 ' A U."'Ll A R Y 0 A W i , Mi

• h *TEL l/ 'l! /

'?UECTicN

• U*

'"/ J u n ; N r[." ' D ' SYSTE:1 pl' /, ' H,' l s E *.CTO R j !/ " / N c'"- U h I" / [ ' d"O P R M/ A'3 Y - A / I' e, j, dSUYP7'/ f, O 8,,,f P.I b \\ ' QQ,,,@'r EEACTOR SYSTE'A - V t c -D, x -<-M dPUMP a. se f c , #'Q'<Us ~ky W;.:sf N J t>e g f,,y t k / \\. :@* sv ; i1 2 ,m. I s.. -MENT

• .y

[ f C'k'%[/ */ ! NA y MUE*'OW I ^ </. s" /'-/ $ h - #- A[(k *24 - (,'s. Y[l[f', R E A C TO R-C OO LA NT d3 FLOW IN PRlM ARY Y 4 ' 9.- FUEL g 'k*,.A ' \\ / N /'.PU?.tPON =, SYSTEA \\' \\.RCCS}l 1 -D(I

• GE NER ATING

_.) 'N ~ S Y S TE?J - STE AY 1 ND WATER FLOW f IN GENER ATING SYSTEM e i y.y/AT ER ~ ..tt:.; ,, c - _ _. ~ Pump cn genera!!ng system and(oods the floor of the cnd r3d:cactive s cam is vented. shuts dc,vn, cutt.ng off aater to containment structure. Some c ste3m generator. rad:3 ton penelr3lcs w3ll 'V The next d3y, r3dicacllvc J') Rc3c!ct h eeps producing Of the structure. wa:eris durrpedinto :ne nver. de ,,7 mwy heat, r3: sing.'ne lemperature s*] The pressure and water 1 More radicactive r'3:cr:21 andpressure of:"e a3: erin levelin lhe reac!ct system dico, is released ficm 3: x!ary "'e primary reac ct system. triggering the emergency coci:rg builc.ng. The reac:ct snuts dcwn system. But an cperatcr snu:s O au!cmatic3!!y. of aff. Some fuelrccs cverhc3: O A radbactive g3s butYe and burst--crpcch3ps cven me!! 13rms at lhe !cp of lM tc3:!cr- 'k V3lde On prCSSurl.'er cpens ll r3lSCS the d3'ger C!3n ex-

== 3S pI3"ned. cut fa 'S !O C!cse. & Sump Sump (?3nsfers r3clc-pVs'Cn Cr fue' rod me:Id Nn ( R3d tactive water gushes :n:c act:ve water :c nearcy au.t:'iary on ess it can te wente)" sh:h:n) o, a few c3ys. ) quezh :ank, an en cver:icws buacing. The tultding ficxs,

n...

- n.-_. .y .,e _.,,,.-,.- -..,.n., ,,..,... c,m .g ' ^* f. '. f.;;; L'r. - E,; l- .. -i, s..'. ' ~ ~ 7 m e_ %..- n d.,,,_.--- ..iw_~ r2 m. ..,._..4

1. }}