ML25197A089

12-11-75 Report on the Tyrone Energy Park, Unit 1

ML25197A089
Person / Time
Issue date:	12/11/1975
From:	Kerr W Advisory Committee on Reactor Safeguards
To:	Anders W NRC/Chairman
References
Download: ML25197A089 (1)

Text

ADVISORY COMMITTEE ON REACTOR SAFEGUARDS NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 December 11, 1975 Honorable William A. Anders Oiairman u.s. Nuclear Regulatory Corrmission wasbingt:co, OC 20555 SOBJOC'l':

RElQa' Ol 'lBE TYROm mERGY PARK, UNIT 00. 1

Dear Mr. Anders:

D.tring its 188th meeting, December 4-6, 1975, the Advisory Co:rmnittee on Reactor: Safeguards reviewed the application of the Northern States Power Conpany of Wisconsin and the Northern States Power Company of Minnesota (Applicants) for a permit to construct the Tyrone Energy Park, Unit No. 1. A visit to the site of the pro:EX)sed plant was made on Noveni:>er 20, 1975, and a Subcoomittee meeting was held at F.au Claire, Wisconsin on November 21, 1975. 'Ihe "Standardized Nuclear Unit Power Plant System* (SNUPPS), to be utilized at the Tyrone Energy Park site and at three other plant sites, was reviewed at Subcorrmittee meetings held at washington, DC, on August 19, 1975, and at Emporia, Kansas on Septeni>er 26, 1975, and at the 185th meeting of the Conmittee, September ll-13, 1975, and the 186th meeting of the Conmittee, October 9-11, 1975. blring its review of the Tyrone Energy Park Unit I, the Comnittee had the benefit of discussions with the Nuclear Regulatory Comnission (NRC) Staff and representatives and consultants of the Applicants, the Westinghouse Electric Cor:EX)ration, the Bechtel Power Corporation, and Comoonwealth Associates, Inc. 'Ihe Comnittee also had the benefit of the documents listed.

'Ihe TyrC>IE unit will be located on a 4597-acre site of partially \\t,OOC]ed rural land about 19 miles southwest of F.au Claire, Wisconsin, the nearest

EX)pulation center (1970 :EX)pulation: about 45,000). 'Ihe exclusion area has a minimum boundary distance of 1470 meters from the reactor centerline.

'Ihe radius of the low population zone is 2.5 miles.

'!be SNUPES will utilize the RESAR-3 Consolidated Version, four-loop, pressurized water reactor with a core power output of 3411 MW(t).

'Ibis design is similar to that utilized at the Comanche J?eak Steam Electric station, Units 1 and 2, reported on by the Committee in its report of <ktober 18, 1974. 'Ihe Corrmittee's review of the SNUPPS was reported on in its ca11away letter of September 17, 1975, and is furthec reported on in this letter.

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Honorable William '!he NRC staff has identified several items in the Tyrone application the reviews for which are not yet completed. '!he Conmittee rec<X111ends that any outstanding issues which may develop in the course of completing these reviews be dealt with in a manner satisfactory to the NRC Staff.

'!he Conmittee wishes to be kept informed on the resolution of the following items:

1. '!he analyses of the effects of anticipated transients with-out scram.

2. '!he evaluation of the plant design to meet the requirements of Appendix I of 10 CFR Part SO.

'!he RESAR-3 Consolidated Version nuclear design utilizes assemblies with the l 7xl 7 fuel rod array. tEstinghouse has completed an integrated test program to confirm safety margins associated with this design. '!he last of a series of reports on this program is expected soon. '!he RESAR-3 reactor core design has been analyzed by l\\estinghouse with respect to stability against radial xenon oscillations. 'i'Estinghouse has agreed to verify this stability in startup physics tests for a 193 fuel assembly core similar to SNUPPS.

'!he Corrmittee will continue to review these matters as appropriate documentation is submitted.

'!he Committee reconmended in its report of September 10, 1973, on accept-ance criteria for ECCS, that significantly improved ECCS capability should be provided for reactors for which construction permit requests are filed after January 7, 1972. '!he SNUPPS design is in this category.

'lhese units will use assemblies with a 17xl7 fuel rod array similar to those to be used in Comanche Peak Steam Electric Station, Units 1 and 2.

Although calculated peak clad temperatures in the event of a postulated LOCA are less for assemblies with a 17xl7 than with a '!SxlS fuel rod array, the Committee believes that the Applicants and the reactor vendors should actively pursue studies that are responsive to the Conmittee's September 10, 1973 report. If studies establish that significant further ECCS improvements can be achieved, consideration should be given to their incorporation into the Tyrone mit.

Although the NRC Staff has concluded-that the Applicants will comply with the Final Acceptance Criteria for the Emergency Core Cooling Systems, the Conmittee wishes to be kept informed on the resolution including possible effects from rod bowing.

'!he Corrmittee believes that the Applicants and the NRC Staff should continue to review the Tyrone plant design for features that could reduce the possi-bility and consequences of sabotage.

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Honorable William 'lhe Committee recorranends that the NRC Staff and the Applicants review the design features that are intended to prevent the occurrence of damaging fires and to minimize the consequences to safety-related equip-ment should a fire occur. 'lhe Corrmittee wishes to be kept informed.

Generic problems relating to large water reactors are discussed in the Conmittee's report dated March 12, 1975. 'lhese problems should be dealt with appropriately by the NRC Staff and the Applicants.

'lhe Advisory Corrmittee on Reactor safeguards believes that the items mentioned above and the items mentioned in its Callaway report, which are relevant to the Tyrone application, can be resolved during construction and that if due consideration is given to the foregoing, the 'fyrone Nuclear Energy Park, Unit No. 1 can be constructed with reasonable assurance that it can be operated without tmdue risk to the health and safety of the public.

References Sincerely yours, IJJ1uN.-

w. Kerr Olairman

1. SNUPPS Preliminary safety Analysis Report with Revision 1 through 13 and the 'fyrone Site Addendum Report with Revision 1 through 6.

2.

RESAR-3 Consolidated Version, Westinghouse safety Analysis Report with Amendments 1 through 6.

3. Safety Evaluation Report, NUR00-75/102 related to the Construction of 'fyrone Energy Park, Unit No. 1, tx>cket No. SIN 50-484, October 1975.

4. letter dated November 21, 1975, from Mrs. Galen C. Radle to Advisory Committee on Reactor safeguards, Nuclear Regulatory Corrmission.

5. SUpplernent No. 1 to the safety Evaluation Report, NUR00-75/076 related to Construction of callaway Plant Units 1 and 2, lbcket Nos. SIN 50-483 and S'l'N 50-486, November 1975.

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