. _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . - _ -

i c Lt.-.

p2180

{ ' {c( kgs UNITED STATES

g NUCLEAR REGULATORY COMMISSIONE WASHINGTON, D. C.,205555

.y / September 30, 1980{j+....

|

Docket Nos. 50-266and 50-301

Mr. Sol Burstet.1Executive Vice PresidentWisconsin Electric Power Company231 West Michigan StreetMilwaukee, Wisconsin 53201

Dear Mr. Burstein:.

During a recent review of the safety analysis for postulated uncontrolledboron dilution events for Millstone Unit 2, the licensee found thatsome non-conservative assumptions had been made for shutdown modes. Anextract of the Licensee Event Report is enclosed for your information(Enclosure 1).

Our review of this matter indicates that there are two plant conditionswhich may not have been conservatively considered with respect to inad-vertent boron dilution:

1. Cold shutdown with the reactor coolant system drained to the " half-pipe" level (reduced RCS volume).

2. Cold shutdown with no reactor coolant pumps running (an effectivereduced RCS volume) .

A review o'f your FFDSAR (Section 14.1.S) indicates that a boron dilutionevent under these specific plant conditions is not addressed.

Based on the foregoing, you are requested to:

1. Recalculate the boron dilution event for these plant conditions,using the reduced RCS volume and 15-minute criteria contained in theStandard Review Plan Section 15.4.6 (Enclosure 2), (Note that unlessa reactor coolant pump is continuously operating, the conservative volumeto be used is the drained down ("l/2-pipe") volume of the RCS plus thatof the residual heat removal system and connecting piping.)

2. Provide a commitment to revise appropriate plant procedures asnecessary to insure that the correct shutdown margin is maintained.

3 Propose revised Technical Specification changes as necessary.

The reanalyses and commitment to revise plant procedr es as necessaryshould be compl eted within 60 days. Proposed Technicul Specif' cationchanges should be submitted to us within 180 days.

80111'90059 THIS DOCUMENT CONTAINSof P0OR QUAUTY PAGES i

, _ _ . . _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ ._

"s, .,

.

.

Mr. Sol BursteinWisconsin Electric Power Company -2-

Please contact us if you have any questions regarding this matter.

Sincerely,,

|(Jjnl E'

Robert A. Clark, ChiefOperating Reactors Branch #1Division of Licensing

Enclosures :1 Millstone LER E0-05,

| 2. SRP 15.4.6

cc: w/ enclosuresSee next page

,.

{

I

,

-

. .*

..

\-

, -.

Mr. Sol Burstein#ff Wisconsin' Electric Power Company -

.

.

cc: Mr. Bruce Churchill, Esquire Mr. Wi.lliam Guidemond~

Shaw, Pittman, Potts and Trowbridge USNRC Resident Inspectors Office;1800 M Street, N.W. , 6612 Nuclear Road.

Washington, D. C. 20036 ,Two' Rivers, Wisconsin 54241

Joseph Mann.L5brary1516 Sixteenth. Street

~

Two Rivers, Wisconsin .54241

Mr. Glenn A. Reed, ManagerNuclear Operations -

Wisconsin Electric Power CompanyPoint Beach Nuclear Plant6610 Nuclear Road

' Two Rivers, Wisconsin 54241.

Walter L. Myer.

Town ChairmanTown of Two CreeksRoute 3Two Rivers, Wisconsin 54241

.

Ms. Kathleen M. FalkGeneral CounselWisconsin's Environmental Decade302 E. Washington Avenue -

Medison, Wisconsin 53703'

.~ ~

Director, Tech'nical Assesscent DivisionOffice of Radiation Programs (AW-459)U. S. Environmental Protection Ag'encyCrystal Mall #2Arlington, Virginia 20460

U. S. Environmental Protection AgencyFederal Activities BranchRegion V OfficeATTN: EIS COORDINATOR230 S. Dearborn Street

'

Chicago Illinois 60604-

.

Chai rmanPublic Service Connission of WisconsinHill Farms State Office BuildingMadison, Wisconsin. 53702_

; .

-

r;-..

. . .

e

o

e

&

f l.

.. . .

. .

,-

._. ,

.

-.

-.

- .

.

. - '

,ATTACHMENT 1~

-

. ,.

,

LER 20-05/lT-0 ,

Hillstone Unit 2Docket No. 50:335* *

..

Event Descriotion -. .

.

During a review of the safety analysis itiwas discovered that an -'

*

incorrect assumption had been made in the analysis of the borondilution event. The analysis of this event while in Mode 5 (coldshutdown) had assuced a full reactor coolant system and a 1% shutdewn

nts resulted in a time to beceme critical of 20 minutesmargin. iwhich satisfied the requirement for the 15 minute maximum time-

assumed for the cperators to raccgnte the situation and takeaction. However, the analysis had not considered the fact thatoperation is possible with the reactor ceciant system drained tothe centerline cf the hot leg. Including this reduced volume ofreactor coolant to ha diluted in the analysis resuits in a time toreach criticality of less than 15 minutes.

. Cause Descricticn and Corrective Actions'

At the reduced system volume the time te reach criticality duringthe Mode 5 dilution avent would have been less than the 15 minutesallowed for the cperator to teminate the event. By increasing therequired shutdcwn cargin in Mode 5 to 2%, a time to criticality ofgreater than 15 minutes is reestablished. l'ntil the necessary

Technical Specification changes can be appr:ved, the unit willadministrative 1y maintain a shutdewn margin in excess of 2% in Mede

~

5. In the past it has been standard practice t; maintain the Mede4 shutdown boron concentration requirement while in Mode 5, whichprovices reasonable assurance that a greater than 2% shutdownmargin has been maintained during previcus Mode 5 operatien.

...-

ee e 9 6 4 8 SW e p & g g , ,

4 9

* * 9e e*

'h O 4 e , ,

9

* e 9 9 .Ge ee e v- o .

O

e

e @

9

e

4

* e

&

J

a, .-_ _ _ _ _ _

,v

.----.- =....::3, ,,,,% * :=-.

-

#1

. [-p.e,g ! STANDARD REVIEW PLAN s-k 'U.S. NU CLEAR REGul.ATORY COMMISSION A,etach..ent 2

'

".M. =. e

*f M7T- OFFICE Or NUCLEAR REACTOR REGULATION {*

+

=.-% <<

'..=:u.

. ..

1*CTICN 13.t.6 C:-:.NICA'. AC VCLUw.E CCN 7.0L SYSTDi FN. FUNCTION 5,

TF.AT RE!"LT5 IN A CECRE;5E IN SCECN CCNCENITdTICN ~;.

IN THE REACTGR CCCf. ANT (F'a''.) 17.' "

=iEElI W TI.S C 515tLTTIES hErir.ar/ - Faaet:r Systs:s Branch (RS3) h=-

*

.

. . --

Se: ndary . Auxiliary and Fewer Conversion Syste-s Branch (AFC53) EE

Core-Perferr.ance Branch (C73) i-

Electrical Instrumentatien and *ontec1 Syste-s Bran:h (EICSE) i~L: ,

':-

E|[5

f I. M E:.5 C7 K rife *.1- .:.~

U.bcrated uter can be added to the rea:ter coolant syste=, via the *emical volume and yc::t.-ci syste: (CYC5), to increase cere reactivity. This c.ty hap;en inadvertently, because j

#!.cf c;-erater er cr or CVCS calfun: icn, and cause an unwanted increase in rea:tivity and*

a decnase in shutdown margin. The c;trater must step this un:lanned dilution before the -|

sh:t.dr n :.a ;ih is eliminated. .Since the setuer.:es of events that may c::ur depend en _,

plar.: c:nditiens at the tire of the unplanned m: terat:r dilutica, the review incluces ]|--

c:nditi ns at the time of the ut;1anned dilutien, such as refueling, starta:, power?:.

nd:"2 c:e-atten (aute.,matic cent ci and r.anual c.: des), het staneby, and cold shut:r.m. -

. ~ . . ~ = . .--

y-'zu-rTr.e revie.' cf p:stulated caderat:r dilutien eve .ts considers causes, initiatin; eve nts,

tre se:vence of events, the analy-ical model, the values Of parameters uset in the ana- k' .=

1.cical ceedel, and predicted cor.setuen:es of the event. [,r."

Tr.e se:vence cf events des:ribed in the a;;,licant's safety analysis re; rt (SAR) is fr vie.-e.d by bc .h the RS5 and EI5*55. The R$5 revie.er c:n=entrates en the need for the jta: :. ; ::ection system and the c;eaater a:tien re:uired to se:ure and maintain the rea:ter f

ir. a stfe c:ndition. The !! CSS reviewtr con:entrates en :ne instrumentatier, and centrols -

ti;e:ts of the se:ven:e described in the SAR te evaluate whether' ?.he rea:::t and plant f;r tection and safeguard: centrols and instruser.tation syste=s will functica as assumed in [the safety analysis witn regard is aut:c.atic actuation, ren:te sensing, indication, control, [

t

and ir.:erle:ks with auxiliary or shared systecs. EIC55 also evalua es p:tential by; ass rt

: des and the ; ssibility :f c.anual c:ntrol by the cperat:7. [:!..

:

USNRC StANO AR|| RIV1EW Fla.N

s . ,. a e w . . .e c. e c . , a... ., anu.......,,c..,.,,, ,

. - - N......--. - . .. aew.c.- ... , . .., ,i,, .

. . . N n . .. - - . . . .. a - s o e m. s ... e . v.. r -. - ..s-.....=.wii...........,

, e , ,.c. . e se. o . n. .

,,-

1~ , . w P.-a. . e .4 ai. .* w S t.-e t '. . '"**.***** -*'-- .*.A

/- . ..i. -- .. - ... ..-,,,

c.,..., - .a . .=2ua., c..so.1

wr. - . e.egu.g 3.C.=uuL

}$ kmm}'9. . . .

.-~~...:..=:~..:.....:2............. . - ...

"~ * " ~ ~ - - 7 - . - , , , , , ,

....:-',.'*:.... . . . . . "~"""" ~""'--

..- . ".?.."."."."""*e-

_-~

-- - " ~ " " ~ "

. .2,----- -

__p-m , . - - - . . - - . . .

_ _ _ _ _ _ _ _ _ -

. 1

.

. .- . . . . ._ -

. The analytical n:thods are' reviewed by RSS to as: rtain whether the ma5hematical m:deling . . .g

." and c::; uter codes have been .previously reviekt and acce;ted by the suff. If a reftrenced - i.E.$..*

=

| . anaiy ical enthod has not been previously revit-ed, the revie-er retuasts C?5 to ir.itiate h.:). .. E..E. .'

a generic evalua:i:n of the new analytical rrtel. APC53 reviews the fun:ticnal and 5_5~~.

c;t.-ational characteristics and potential fat!:re modes of the CVCS, as described in EE|'

Standard Eeview Plan (SRP) 9.3.4. ,ine F.53 reviewer cakes use of this review to evaluate fj[5[= . . =initiating causes and the expected sequence cf events.

..

r..

. The predicted results of moderator dilution events are revie.ed to assure that the ${c:nse:uen:es meat the acceptan:e criteria give. in Se:tien II of this SK7. Further,

' the results of the transients are reviewed to ascertain that the values of pertinent E:: |r. .: ;

system parameters are within ranges expected fer the type and class of reactor under [:_:E:==

' t==review. w=.====:=

II. A:CI?TANCE CRITERIA ;==.

1. Tne general cbje::ive of the review of c,:.derater dilutica events is to confim that g. . = - -

either of the following c:nditiens are met: =.:

= = . . !,

'The consecuences of these events are less severe than the consequences of ancther f*a.

transient that results in an une:nt :lled in:rease in reactiv,ity and has the same .rii:,= .

anticipated frequen:y classification. 5=.

= _ ._ . . .-'

-

b. The plant res;cnds :: the events in such a way that the criteria recarding fuel, e. g.;da;-. age and system pressure are met and adecua:e ti=e is allowed the c; erat:r to -

[Eteminate the dilutien before *he st;td:en car;in is eliminated. ( =-- 5

2. ine specific criteria for :noderater dilu:f on events are: 5=.5..,.

.==P. essure in the rea:::r c clant and r. tin steam systems should be maintained below Ea.

11Ct cf the design pressures (Ref.1). h---

..:.

b. Fuel clad integrity should be maintaine-d by ensuring that Se: tion :I, A::eptance i:=

Criterien 1 cf SR? 4.a is satisfied th-: ugh ut the transien:. =

=.T;

.:

:. Such incidents will not senerate a r.:re sericus ;1 ant ::ndition without other faults E.-

cecurring indepencently. :3::

:=

.-e- tne tiee en e h- - bs the e e-at:- awe-e :' um i -s ~ d=- ?- enud e , the"

::. ='511cain; minimum ti:e intervals =;s. 54 avaiiatie bef:re a less of shutdec :

E-:margin c::urs:-:*

::(1) During refuelir.;; 20 minutes.E:.

(2) Durin; starte; =cid shutde .. n:t stan::y, tr.: ;;wer o; era:ien: 15 minutes. ;:

-~0:

E.'~ " " * ..e....~,

1 :, . , . :, ,4 :...-

.....#NQ

11/2:/75

._---:..==-.. ---

. ._.

.. ._- ...-: :. . . . _

r ,

*.

* a-3. The applicant's analysis of coderator dilution events sh:uld be ;:rfer=:d using an .]

._

' tc:eptable analy,tical m del. The~equatio'ns, sensitivity studies, and c:dels des- g'

., .

cribed in References 2 thr: ugh 4 are a:ce;:able. Sh:uld other analy:ical meth:ds M.._*

- .. . . .

.

te proposed, these ce:heds east be evaluated by the staff. For new ger.eric methods, E..~

3_.' .:the reviewer requests an evalcati n by'C?5. .*:

:=_ =..

All of the follodng plant initial conditiens sh:uld be c:nsidered in the analysis: {refue'.ing, startup, power c;eration (aute:atic centrol and =anual c: des), het _5--

,

..standby, and c:1d shutdown. =_=._

=_ -=

' Be parameters and assu=pti:ns used in the analytical e,: del sh:uld be suitably con- :]=s erva tive. The following values and assu:;; ions are considered acceptable: $

. - -=.':~

Fcr analyses durin; ;:.er ::eratien, the initial p:-er level is rated cutput isa. .:.

(Itcensed c:re thereal ;cwer) plus an allowance of 2 te a:::un: fer power j5t==measurement uncertainty.

:=b. The boren dilutien is assu=ed to oc:ur at the e.aximum possible rate. *E

a_. t.=

The core burnup and corres;ondin; b:r:n concentra:ica are sele: ed to yield the 3c.most limiting c::bination of moderater tem;trature cesfficient, veid coefficient, jg0:ppler c: efficient, axial ;: er ;r: file, and radiai power distribution. This 55

==will usually be the be;innici.:f-life (50'.) conditicn. !E

===::=

' Ei d. All fuel assemblies are installed in the core. gC.*.

5.=re. A c:nservatively low value is assumed fer the rea:::r cooler.: vol =e. =.:-E

f. Fer' analyses during refuelin;, all cent-ci rods are withdrawn fr:m the core. @7.==

;. For analyses during ;:-er c;eratten, the minitu shutscwn margin alicwed by {,

the technical spacifications (usually 1%) i: assumed to e.xis: price to the =.=-

initiation of beren dilution. =.=-:==

h. For each event analy:ed, a c:nservatively high reae:fvity additi:n rate is 3assumed takin; into ac:cun: the effe:: cf increasin; boren worth with dilution. @

-..:-==

i. Conservative scra: characteristics are assced, i.e., maxt== tire celay with E=

:ne mes reactive rod neid Out cf tne ::re. E_.=.=.

I n. . :. .. .e. :. g ::.v..eme rs = . .. . _ -

De :-::edures below are used during both the c:nstruction pe-=it (C?) and coeratin; license-

(r.} . eviews. During tr.e CF review, ne values of system :arameters an: sa: ; ints use-d in gtr.e a .alysis will be preliminary in ..atu.-e and sub.de:: :: enan;e. A: :ne C'. review, finai

.}.vai es will be used in ne analysis, anc the revie.<er sh:uid ::::are taase 7 :ne limitin; g

saf t:y system se::ings in:luced in the pr:: sed te:hnical s:e:ificatier.s. _g='

-- 15. .: .6 3 g=;-

$.-.-

;{*n /24'75

>

-

b - .-ex>~._.. 2 . . . . . . . . . . . . . . . _ , __ _ ,_ __

_

.

e

Metropolitan Edison Companyy.c:e .- - ar ,

j- ) Post 0+t.c. Bo. '80i l ! . , '- *6

. a...IL ! /J T.; .I. t.

M n:Heine. . Pr nt . .a 2 170E-'

ec.t . , p.r c. p y % .

NoveFrer 14 , 1C

T. u .. .e, c. A.t

'D:I Proc rn-- OfficeAt:n: Mr. John T. Collins, Denut'. Director

U. S. Suclear Regulatory Coccission

c/o Three Mile Island Nuclear StationMiddletown, Pennsylvania 17057

Dear Sir:

. , . ,-

Three Mile Island Nuclear Station, l,nl: (t.u.. ->Operating License No. DPR-73

Decke: No. 50-320Status of Proprietarv Documente

Two proprietarv d ec ur.en t s relatinc to the EPICOR Radraste F"Ete wer-

f orwa rde :' to the ''TC as follows:

TLL 3 9, cared 7/16/50 " EPIC 0F, II Resin Irradiation ?atc""

TLL ':: . dat e d 9 '0 5 /8 0 "Evaluat ion of EP ICnR II '..~a s t e -

Deter-ination of ';RC acceptance of these documents as beinc croprietar.has net been received. It is recuested the ':RC provide a status of, and

a date when thi.a deternination will be made. The status of TL 3 0 i: c'

particular i . tere s: since this letter has been in : "RC'.c pec c e s s ir-

for fcur (4) cor.:' c

Sincerelv,

!s| : n Hy e-

c . R. Nevev i c e..vrcs1 >: .- v-

Direc:ar, T ::-:

G"H:R2': dad

cc: r.ernara :. sr 2 :

Tms DOCUMalT CGIIT''-}IISi

;

POOR Q.UWTY Wsuo 1-.

I

\

8 011250 '2,h.

: - ..

=g

b

1 J

___-

'' TMI-2 Corrsspondenem

(bec list)'

Mr. E. L. Blake, Jr. Dr. Steven Long, Director

Sh!.w, Pittman, Potts, & Trowbridge Power Plant Siting Program

1800 M Street, N.W. Department of Natural ResourcesW2thington, D.C. 20036 Tawes State Office, Building B-3

580 Taylor AvenueMr. A. S. Dam Annapolis, Maryland . 21401Burns and Roe, Inc.

650 Winters Avenue Mr. Thomas Gerusky, Director

Paramus, New Jersey 07652 Bureau of Radiation ProtectionPA Department of Environmental Resources

Mr. T. F. Hartley, Jr. Fulton National Bank BuildingMarsh and McLennan, Inc. Harrisburg, Pennsylvania 17120

1221 Avenue of the AmericasNiw York, New York 10020 Mr. Kent Hamlin

American Nuclear InsurersMrs. Pat Higgins The Exchange - Suite 245Edison Electric Institute 270 Farmington Avenue1111 19th Street, N.W.

' Farmington, Connecticut 06032

Wxshington, D.C. 20036w - C_r d % s}on ]w__ -

Mr. George Kulynych c/o Document Management BranchBabcock and Wilcox, Inc. Washington, D.C. 20555

P.O. Box 1260Lynchburg, Virginia 24505 LERs ONLY

Mr. Bill LavalleeH Nuclear Safety Analysis Center.

d P.O. Box 10412.0. Box 88 Palo Alto, California 94303

Middletown, Pennsylvania 17057

*******

G. K. Hovey, Director TMI-2, Admin. Building W. F. Schmauss, TMI-2 GRC Chm., ParsippanyP. R. Clark, GPUSC Parsippany A. S. Bell, TMI GORB Sec., ParsippanyR. Fenti, Trailer 22 - QA M. A. Nelson, THI-l PORC Chm., Trailer 60J. J. Barton, TMI-2 Admin. Building M. A. Shatto, TMI-1 PORC Sec., TMI-IL. W. Harding, TMI-1 Licensing, Trailer 68 G. A. Kunder, TMI-2 PORC Chm. , Adm. Bldg .N. Kszanas, Parsippany - QA D. C. Carl, TMI-2 PORC Sec., Admin. Bldg.J. F. Wilson, TMI-2 Admin. Building B. A. Hockley, Discovery rm., Crawford St.J. G. Herbein, Trailer 118 J. Theising, Bechtel, green buildingB. Ballard, Trailer 16 R. L. Rider, Bechtel, TMI-2 Admin. Bldg.G. P. Miller, TMI-1 P. S. Walsh, GPU Parsippany

R. C. Arnold, TMI-2 Admin. Bldg., and D. Buchanan, TMI-2 Admin. Buil/ingParsippany B. D. Elam, TMI-2 Admin. Building

D. G. Mitchell, Trailer 68 J. J. Chwastyk, TMI-2 Admin. BuildingS. D. Chaplin, TMI-2 Admin. Building G. J. Troffer, Trailer 198

R. A. Knief, Trailer 118 G. Mencinsky, Parsippany

J. C. DeVine, TMI-2 Admin. Building J. Brasher, TMI-2 Admin. BuildingR. W. Heward, Parsippany W. N. Moreau, Parsippany

J. T. Collins, NRC Trailer 1 E. G. Wallace, Licensing, ParsippanyR. F. Wilson, Parsippany L. Smith, Parsippany - DDCC

FILE (7)

54

J