ML25196A330
| ML25196A330 | |
| Person / Time | |
|---|---|
| Issue date: | 02/11/1976 |
| From: | Moeller D Advisory Committee on Reactor Safeguards |
| To: | Anders W NRC/Chairman |
| References | |
| Download: ML25196A330 (1) | |
Text
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 Honorable William A. Anders Olairman U.S. Nuclear Regulatory Conmission
'Washington, DC 20555 February 11, 1976 SUbject:
REPORT CB SWESSAR-Pl, ~
AND WEBSTER ~
CORPORATICB BAIANCE-OF-PIAN'l' DESIGN
Dear Mr. Anders:
At its 190th meeting on February 5-7, 1976, the Advisory Conmittee on Reactor Safeguards reviewed the a:wlication of the Stone and webster Engineering Corporation for a Preliminary Design Approval of its SWESSAR-:1.>1, a stand-ardized nuclear balance-of-plant (BOP) design.
SWESSAR-Pl had previously been reviewed at Subcarmittee meetings held in <llicago, Illinois, on August 1, 1975, and in Washington, DC, on January 22, 1976. niring its review, the Coomittee had the benefit of discussions with representatives of the Stone and Webster Engineering Corporation and the Nuclear Regulatory Conmission (NIC) Staff. 'll1e Conmittee also had the benefit of the documents listed.
'lhe bliESSAR-Pl BOP design would interface with single unit pressurized-water-reactor nuclear islands of standardized design such as RF.SAR-41 and CESSAR-80.
'lllis review is limited to RFSAR-41.
'!he interface requirements with other standardized nuclear island designs have not yet been established.
'lhe SWESSAR-Pl containment is a conventional reinforced-concrete-steel-lined building with a flat base, a cylindrical shell, and a hemispierical dane.
It is surrounded by an annulus building extending about one4lalf the height of the containment building. 'llle contaimnent and the annulus buildings are SUJ:P)rted on a common base mat. 'llle annulus building contains portions of the engineered safety features and some auxiliaries. '!he turbine generator is housed in a separate turbine building with its axis oriented radially with respect to the containment structure. Separate buildings are provided to house the diesel generators, the control facilities, md the radioactive waste disposal equipnent.
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Honorable William February 11, 1976 A set of design parameters has been established for b"WESSAR-Pl which enable it to be applied to a range of sites without site-specific-design treatment of many features. '!he design was reviewed for a power level of 3800 MWt and 'WOuld accept seismic loadings equivalent to 0.30g horizontal ground acceleration for the safe shutdown earthquake (SSE) and 0.15g horizontal ground acceleration for the operating basis earth-quake (OBE).
SWESSAR-Pl 'WOuld be usable under meteorologic conditions prevailing in 22% of the more than 40 sites reviewed in this context by the NBC Staff.
An optional extension of the annulus building to enclose the entire containment structure 'WOuld permit SWESSAR-Pl to acocmoodate meteorological conditions at most sites thus far licensed. Other site conditions such as tornado design requirements, missile resistance, flood design limits, and postulated pipe rupture effects inside and outside containment are canparable to those now being required in licensed nuclear power plants. '!he remaining related design features such as offsite power, ultimate heat sink, and condenser cooling water supply and return, 'WOuld be individually selected to suit the site on which SWESSAR-Pl is used.
'!he arrangement of SWESSAR-Pl provides extensive physical separation of critical safety-related equipnent to protect agaL"lSt COJ1100n mode failures associated with fires or other operational contingencies. However, can-plete design details for SWESSAR-Pl have not been developed and the concept has not yet been applied to a complete nuclear power plant design.
Consequently, further review of the physical separation arrangement should be made prior to the Final Design Approval or when SWESSAR-Pl is proposed for a nuclear power plant for which a construction permit is being sought.
'!he Conmittee wishes to be kept informed.
A matter of major concern in the NRC Staff's review has been the safety-related interfaces between the SWESSAR-Pl BOP design and the Rm;AR-41 NSSS design, on one hand, and the custom-designed site-related structures and canponents, on the other hand. 'lhe responsibilities and requirements related to the SWESSAR-RESAR interfaces have been defined in detail in the safety Analysis Reports for these two standardized designs. '!he Conmittee believes that these interface requirements are satisfactory for a Preliminary Design Approval, but expects the NRC Staff and the Applicant to continue to examine them further in comection with the proposal to use these designs for an actual plant when it is reviewed for a construction permit. '!he interfaces between SWESSAR-Pl and the site-related features are defined in the SWESSAR-Pl safety Analysis Report, but have not yet been subjected to the test of a complete design for a nuclear power plant. '!he NRC Staff should review these interfaces in greater depth when a construction permit application is received.
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Honorable William February 11, 1976
'!he Conmittee. recoimends that, during the design, procurement, construc-tion, and startup, timely and awropriate interdisciplinary system analyses be performed to assure complete ftmctional compatibility across each interface for the entire spectrum of anticipated operations and postulated design basis accident conditions.
'!he coordination of interdepeooent instrumentation and controls in the nuclear island and in the balance of plant will require attention at the time when SWESSAR-Pl is used as a portion of a nuclear power plant license application.
'lhese matters should be included in the NRC Staff's standard review plans.
'!he proposed orientation of the turbine-generator with respect to the nuclear island is suitable for a single tmit installation. For multiple tmit power plants, the location and orientation of the tmits should be such as to yield acceptably low probabilities of damage by low-trajectory turbine-generator missiles, or suitable missile shielding should be pro-vided.
Although SWESSAR-Pl includes provisions for protection against industrial sabotage, the Conmittee believes that further steps can be taken beyond those in SWESSAR-Pl and in the custan plant designs about which the ACRS has previously expressed concern. Prior to the use of SWESSAR-Pl as a portion of an application for a nuclear power plant license, the Utility-Applicant should be required to demonstrate that acceptable industrial sabotage provisions will be incorporated into the plant design.
'!he SWESSAR-Pl design should include provisions which anticipate the maintenance, inspection, and operational needs of the plant througt,out its service life, including cleaning and decontamination of the primary coolant system, and eventual deconmissioning.
In particular, the Conmittee believes that the NRC Staff and the Applicant should review methods and procedures for removing accumulations of radioactive contamination whereby maintenance and inspection programs can be more effectively and safely carried out.
Generic problems related to large water reactors are discussed in the Conmittee's report dated March 12, 1975. '!hose problems relevant to
&WESSAR-Pl should be dealt with appropriately by the NRC Staff and the Applicant as solutions are found.
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&:>norable William February 11, 1976 1be Advisory Comnittee on Reactor safeguards believes that the items mentioned above can be resolved during the standardized plant licensing process and that, if due consideration is given to the foregoing, Pre-liminary Design Approval for SWESSAR-Pl to be used in conjunction Ylith RESAR-41 can be granted in accord with the spirit and purposes set forth in the Comniasion's policy statement on standardization of nuclear power plants as described in WAml-1341, "Programmatic Information for the Licensing of Standardized Nuclear R:Jwer Plants" and in conformance with the Regulations of Appendix Oto Part 50 and Section 2.110 of Part 2 of Title 10 of the COde of Federal Regulations.
Sincerely yours,
~v.~
leferences Dade w. lt>eller Chaiman
- 1. Pressurized water Reactor Reference Nuclear R:Jwer Plant safety Analysis Report (&WESSAR} and.ArnemDEnts 1 through 20.
- 2. Stone and Webster Engineering Corporation letters:
- a. April 8, 1975 - Containment and Subcompartment Analy~is
- b. April 18, 1975 - Subcompartment Analysis
- c. April 29, 1975 - Schedules
- d. April 30, 1975 - Steam Pipe Break Analysis
- e. June 4, 1975 - Implementation of WASH-1341
- f. June 5, 1975 - Supplementary leak Collection.and Release System
- g. September 5, 1975 - Reactor cavity Nodulization Study
- b. September 5, 1975 - Schedules
- i. September 11, 1975 - Electrical System
- j. September 29, 1975 - Boron Recovery System
- k. October 2, 1975 - Interface Data
- 1. November 13, 1975 - Supplementary leak Collection and Release System
- m.
November 21, 1975 - Resolution of Outstanding Items
- n. November 26, 1975 - Electrical, Instrumentation and Control Systems
- o. December 9, 1975 - Soil-Structure Interaction 3566
Honorable Willaim A. Anders
-s-February 11, 1976 Reference - Continued
- 3. Report to the Advisory Conmittee on Reactor Safeguards in the Matter of Stone & 'Webster Engineering Corporation Standard Safety Analysis Report PWR Reference Nuclear R:>wer Plant SWESSAR-Pl (and its relationship to the RESAR-41 Standard NSSS ~sign) I))cket No. S'lN 50-495, Published:
O:::tober 1975, u. s. Nuclear Regulatory Coomission, Office of Nuclear Reactor Regulation.
- 4. SUpplement No. 1 to the Report to the Advisory Committee on Reactor Safeguards in the Matter of Stone & 'Webster Engineering Corporation Standard Safety Analysis Report PWR Reference Nuclear :Ebwer Plant s-lESSAR-Pl (and its relationship to the RESAR-41 Standard NSSS ~sign)
Docket No. S'lN 50-495, January 1976, u. s. Nuclear Regulatory Conmission, Office of Nuclear Reactor Regulation.
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