ML25196A512
| ML25196A512 | |
| Person / Time | |
|---|---|
| Issue date: | 06/11/1975 |
| From: | Kerr W Advisory Committee on Reactor Safeguards |
| To: | Anders W NRC/Chairman |
| References | |
| Download: ML25196A512 (1) | |
Text
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS NUCLEAR REGULATORY COMMISSION WASHINGTON. D. C. 20555 June 11, 1975 Honorable William A. Anders Olairman
- u. s. Nuclear Regulatory Commission Washington, D. C.
20555 subject:
REPORT 00 WASHING'ION PUBLIC PCXrmR SUPPLY SYSTEM NUCLFAR :E'CMER STATIONS WNP 1 and 4
Dear Mr. Anders:
At -its 182nd meeting, June 5-7, 1975, the Mvisory Committee on Reactor Safeguards completed its review of the application of the Washington PUblic ?ower Supply System for permission to construct the Washington Nuclear Power (WNP) Stations 1 and 4.
'lhese plants were previously considered at a Subcommittee meeting on May 16, at Richland, Washington, and the site was visited on May 15, 1975. niring its review the Cormtittee had the benefit of discussions with representatives of Washington Public Power Supply System and consultants, the Babcock and Wilcox Company (B&w), and the NRC staff. '!he Comnittee also had the benefit of the documents listed.
'!he WNP Station site is located on the Energy Research and Developnent Administration's Hanford Reservation in Benton County, Washington, eight miles north of Richland, Washington, the nearest population center (1970 population 26,290). '!he exclusion radius is 6400 feet. '!he low population zone is four miles in radius.
In 1970 there were 38 residents within the low population zone.
'!he Fast Flux Test Facility and WPPSS Hanford-2 (WNP-2) Reactor are the only installations within the low population zone.
'!he safe shutdown earthquake is 0.25g horizontal acceleration at the foundations. '!he operating basis earthquake is 0.125g.
For shutdown heat removal the plant has two sources of water, the operating water supply from a river intake on the Columbia River, which is not Seismic Category I, and Seismic Category I spray ponds designed to provide a 30 day emergency water supply for each unit.
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Honorable William 'llle nuclear steam supply system supplied by B&W is identical in design to that of Bellefonte Nuclear Plant,Units 1 and 2, previously reported on in the ACRS letter of July 16,1974.
'!be design operating power is 3600 MW(t). '!be reactor core June 11; 1975 will use 205 B&W Mark C (17xl7) fuel assemblies. 'llle Conmittee reconmended in its report of January 7, 1972, on Interim Acceptance Criteria for OC'CS, that significantly improved ECCS capability should be provided for reactors for which construction permit applications were filed after January 7, 1972. 'Ibis position was repeated in its report of September 10, 1973, on Acceptance Criteria for ECCS. '!be Mark c fuel assemblies are responsive to this reconmendation. '!be new fuel assemblies will be operated at lower linear heat generation rates and are expected to yield greater thermal margins for f.uel design limits and improved safety margins in the analyses of the loss of coolant accidents, An extensive program has been initiated for determining the mechanical and thermaljhydraulic characteristics of the new fuel assemblies. A program of control rod tests also
- is proposed, incltxling testing of trip times and control rod wear. Should modifications become necessary as a result of the control rod tests, retesting ~f the entire control rod drive would be undertaken. While many of the details of the proposed design are available, complete analyses of the performance of the Mark C fuel are not yet available, and the NRC Staff has not completed its review. '!be Comnittee reserves judgment concerning the final design until the required performance information is presented and has been reviewed. '!be Committee reconrnends that the applicant continue sttxlies directed at further improvement in the capability and reliability of the ECCS. '!be Corrmittee wishes to be kept informed.
'!be NRC Staff has determined that the ECCS performance evalua-tion for WNP Stations 1 and 4 meets the Interim Acceptance Criteria of June 1971. In addition the Applicant's ECCS performance evaluation, using an approved B&W model, to show compliance with the Final Acceptance Criteria of 10CFRS0.46 and Appendix K~ must be reviewed and approved by the NRC Staff. '!be Comnittee wishes to be kept informed.
'!be applicant proposes to utilize a new reactor protection system designated as RPS-II. '!be system, a hybrid using both analog and digital techniques, represents an evolution from the analog system, RPS-I, currently in use*in the Q::onee reactors.
'llle applicant has proposed a series of environmental, reliability, and in situ tests for qualification of this system prior to 1786
Honorable William its use in Bellefonte Units 1 and 2, the lead plant. 'Ibis matter should be resolved in a manner satisfactory to the NRC Staff.
A problem considered to be generic by the ACRS is the environ-mental and seismic qualifications of Class I instrumentation and electrical equipnent.
An important aspect is that of defining what represents an acceptable aging procedure for multi-component systems. 'Ibis issue should be resolved by the applicant and the NRC Staff. '!be Committee wishes to be kept informed.
A question has arisen concerning loads on the vessel support structure for certain postulated loss-of-coolant accidents in pressurized water reactors. 'Ibis matter should be resolved for the WNP 1&4 Plants, in a manner satisfactory to the NRC Staff.
G:!neric problems relating to large water reactors have been identified by the NRC Staff and the ACRS and discussed in the COltmittee*s repo~t dated March 12, 1975. 'lbese.
problems should be dealt with appropriately by the NRC Staff and the applicant.
'!be Mvisory Comnittee on Reactor safeguards believes that the items mentioned above can be resolved during construction and that, if due consideration is given to the foregoing, the Washington Public Power SUpply System Plants WNP 1 and 4, can be constructed with reasonable assurance that they can be operated without undue risk to the health and safety of the public.
References Attached.
Sincerely yours, William Kerr Chairman 1787 June 11, 1975
Honorable William June 11, 1975 References
- 1.
Preliminary safety Analysis Report, Washington Nuclear Projects 1 and 4.
(Including Amendments 1 thru 17).
- 2.
"Safety Evaluation of the Washington Nuclear Projects 1 and 4", NOREG - 75/036, Docket Nos. 50-460, 50-513, May, 1975, ONRR, u. s. Nuclear Regulatory Commission, Washington, D. C.
- 3.
WPPSS Letter dated May 14, 1975, J. J. Stein to Angelo Giambusso, DRL, ONRR, USNRC,
Subject:
WPPSS Nuclear Projects Nos. 1 and 4, en-site Meteorological data.
- 4.
SUpplement l to the safety Evaluation Report, Letter from voss A. ~'bore, Asst. Dir. for Light Water Reactors, Group 2 Division of Reactor Licensing, USNRC to Dr. William Kerr, Oiairman ACRS dated June 2, 1975.
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