ML20052F322

Addendum to Wi Environ Decade 820503 Motion for Reconsideration of Part II of ASLB 820422 Memorandum & Order Re Motion to compel.NUREG-0909 Re Ginna 820125 Tube Rupture Adds & Strengthens Motion.Certificate of Svc Encl

ML20052F322
Person / Time
Site:	Point Beach
Issue date:	05/07/1982
From:	Patricia Anderson WISCONSIN'S ENVIRONMENTAL DECADE
To:	Atomic Safety and Licensing Board Panel
References
NUDOCS 8205120346
Download: ML20052F322 (5)

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e 00C verp, 09;b WED-05/07/82-P3:50266NRC.P43 UNITED STATES OF AMERICA E2 thYt y Ald:59 L .=r NUCLEAR REGULATORY COMMISSION - . ,YU 006.M.[itk[pf,7 2.4, , H'.i .

Before the Atomic Safety and Licensing Board

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& 'b Wisconsin Electric Power Company POINT BEACH NUCLEAR PLANT UNITS 1 & f ggCEW60 DOCKET NOS. 50-266 AND 50-301 - 4 gg l'1 NW

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Operating License Amendment ~

(Steam Generator Tube Sleeving Progr. g. 'gf }

ADDENDUM TO DECADE'S MOTION FOR RECONSIDERATIO c xF BOA}03 #

MEMORANDUM AND ORDER COMCERNING MOTION TO C E

%i ns By filing dated May 3, 1982, Wisconsin's Environmental Decade, Inc. ("Dec ade ") moved the Atomic Safety and Licensing Boa rd (" Boa rd") for reconsideration of Part II of the Memorandum and Order Concerning Motion to Compel, entered April 22, 1982.

In that Motion, we argued that certain actions taken to ameliorate thermal shock could increase the consequences of a tube rupture following a loss-of-coolant-accident ("LOCA").

Subsequent to filing that Motion, we have received and reviewed a recent document issued by the_ Nuclear, Regulatory-Commission (" Commission") describing the a nu'a r y 2 5, 19"8 2 ' tiub e ,

rupture at Ginna Nuclear Plant. NRC Task Force, HRC. Reoort an ibn January 2h 1181 Steam Generator Tube Rupture A_t; R L Ginna Nuclear Power Plant (Apr. '82), NUREG-090 9 ("Ginna Repo r t") .

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~950 q That Report raises new questions concerning the thermal j g shock problem that strengthen our earlier Motion, and, for that reason, the Decade makes this addendum to it). original. filing to 8205120346 820507 PDR ADOCK 03000266 G PDR

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.. 4 reflect these new facts.

Specifically, the original Motion contended, among other things, that recongifuration of the reactor core of Point Beach by the Licensee could increase the cooling requirements of the core at the same time as tube f ailures during LOCA would reduce rerlood rates. This is due to secondarv-to-primary in-leakage.

The Ginna Report points out that thermal shock is related to tube failures from an entirely separate sequence of events due to p_ Lim a rv-to-seconda ry leak age. At Ginna, the accident was not precipitated from a break in the reactor coolant piping that caused instantaneous pressure reversal followed by collapse of steam generator tubes and in-leakage of steam. Rather, the Ginna accident was initiated by the tubes themselves rupturing, followed by otner serious consequences, as are described in the .

Ginna Report:

" Based on Task Force analysis of available data f rom the instrumentation installed at Ginna, sionificant thermal shock nf the reactor pressure vessel has not been ruled Alt.

Significant thermal shock to the reactor pressure vessel wall could ocen; as a result of its exposure to the approximat aly 90 F water f rom the saf ety injection system after the reactor coolant pumps were tripped. During this event, the indicated temperature transient in the reactor coolant system cold-leg loop piping attached to the intact -

steam generator and the calculated magnitude of natural f j circulation flow precludes significant thermal shock to the i j reactor pressure vessel from safety injection flow into that I

loop. However, the indicated temperature transient in the cold-leg loop piping attached in the f aulted stean cenerator does nni by itself oreclude the oossibility nf sionificant thermal shock from safety injection 12 this loop. II.e Task l Force was able to closely approximate the indicated -

temperature transient of the f aulted steam generator loop g with a model which assumed flow toward the break location. y The results of this model suggested that safety injection flow to the f aulted loop may not have caused significant thermal shock to the reactor vessel."

Ginna Report, at p. 1-11.1 [ Emphasis added]

i That is to say, the NRC Task Force investigation of the Ginna accident concluded that an event initiated by the rupture-of a single tube could lead to thermal shock of the reactor vessel.2 .ld.

In turn, we know that thermal shock can cause a crack in the brittle steel of a reactor, Memorandum from D. G. Eisenhut to All  ;

Licensees, dated April 20, 1981, re Thermal Shock to Reactor l Pressure Vessels (Generic Letter 81-19), and that the design of a i nuclear plant doe:h not provide any protection against reactor vessel failure, Resolution af tJ1g Reactor Vessel Baterials Touchness Saf ety Issue (1981), NUREG-0744, at p. A-1.

The Licensee has only been able to provide assurances concerning adequate reactor vessel f racture toughness at Point Beach Nuclear Plant through October 1985. Letter from C. W. Fay to Harold R. Denton, dated January 15, 1982.

A Ginna-type accident has happened three times previously in this country, including once before at Point Beach. Ginna Report, at p. 3-4 4. Sleeving intended to counteract tube corrosion has been shown to weaken tubes and cause them to leak. Office of ,

Nuclear Reactor Regulation, Items nf Interest, Week Ending March s f

26, 1982, San Onofre Unit 1.

Therefore, Commission documents indicate that a tube rupture at Point Beach from a sleeve induced failure could lead to a reactor core meltdown at Point Beach were it to occur after p October 1985.

e The Decade believes that~ these newly reported facts l=

l demonstrate that the scope sf this hearing must be expanded to ,[

n l embrace all embrittlement issues so that all significant safety y l D

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concerns related to sleeving will be considered. This means not .

only reconsidering the Board's April 22 Memorandum and Order Concerning Motion to Compel, but also granting the Decade permission to expand the preliminary contentions set forth in its letter dated January 18, 1982, to include the following in addition to 19:

"(9a) Sleeve induced tube f ailures may cause thermal shock and reactor vessel f ailure."

DATED at Madison, Wisconsin, this 7 th day of May,1981.

WISCONSIN'S ENVIRONMENTAL DECADE, INC.

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by '

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PETER ANDERSON Director of Public Affairs 114 North Carroll Street Suite 208 Madison, Wisconsin 53703 (608) 251-7020 fitsLtnotes 1 With regard to the last sentence of this quotation, it may be noted that the carefully guarded statement that thermal shock may not have occurred is predicated upon a series of complex and unverifiable assumptions derived from inferred, not actual, data concerning the possibility of a reverse flow rate in the cold leg over a significant period of time.

Ginna Report, at 3-39. In any event, it should be emphasized the question in the case at bar is not whether thermal shock occurred in fact at Ginna or was narrowly averted on this occasion, but rather whether it is possible thermal shock could occur at Point Beach during a tube failure event in the future.

2 This is because recirculation through the steam generator without a tube rupture will have the cold safety injection water mixed with sufficient hot water that has been heated by the core to raise the temperature of the emergency core cooling water above the level at which thermal shock is a problem. But, in the cold leg that leaves the steam generator with a major tube rupture, a significant part of the heated recirculating water will have leaked out of the ruptured tube. Thus, there will be less hot water to mix with the cold safety injection and the water reentering the core may be sufficiently cold to crack an embrittled reactor vessel. Ginna Report, at p. 3-39.

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UNI'IED S'IA'IES OF NERICA NUCIFAR REGUINIORY COM4ISSI0ti

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..* y Wisconsin Electric Power Conpany POINT BEICI NUCIEAR PINiT UNI'IS 1 & 2 ;F:

GCM 'd1NC

.; '. i3[Iky Ibcket Nos. 50-266 and 50-301

CERTIFICNIE OF SERVICE I certify that true and correct copies of the foregoing docment will be served this day by depositing copies of the same in the first class miils, i postage prt% and correctly adama=~1, to the following: ,

Peter B. Bloch, Chaintun Atomic Safety & Licensing Board U. S. Nuclear Pegulatory Cr=niacion Washingttsn, D. C. 20555 Dr. Hugh C. Paxton  !

1229 -41st Street Ios Alanca It ' Mexico 87544 Dr. Jerry '.L Kline Atomic Safet.'y & Licensing Board U. S. Nuclear Ibgulatory Crmniasion Washington, D. C. 20555 Ibcketing & Service U. S. Nmlear lbgulatory Comnission Washingtcn, D. C. 20555 Mr. Richard Bachnunn Office of Emcutive Iagal Director U. S. Nuclear Beguliitory Ctrominairvi Washingtcn, D. C. 20555 Mr. Bruce W. Churchill Shaw Pittwn Potts and Towbridge 1800 M. Street N.W.

Washington, D. C. 20036 Barton Cowan 42nd Floor 600 Grant Street Pittsburga, PA 15219 j Ju-l)uku.

Carol Pfeffdrkorg MM: f'7"id

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