ML20150D950

Status of Commission Readiness to Process HTGR CP Application

ML20150D950
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Issue date:	02/29/1988
From:	NRC
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NUDOCS 8803250229
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O Enclosure STATUS OF COPMISSION READINESS TO PROCESS AN HTGR CONSTRllCTION PERMIT APPLICATION February 1988 1

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l 0803250229 880302 PDR COMMS NRCC CORRESPONDENCE PDR l

4 TABLE OF CONTENTS PAGE I. Introduction and Summary 3 II. Background 3 A. HTGR Regulatory History 3 B. Activities of Office of Nuclear Regulatory Pesearch 3 C. Fort St. Vrain Experience 4 D. Foreign Reactor Experience A III. Current Activities 5 A. Interactions Between NRC and 00E 5 B. Interactions with ACRS 5 C. Technical Assistance and Staffing 6 l

0. Regulatory Preparation 6  :

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!Y. Conclusion 7 l

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3 I. INTRODUCTION AND

SUMMARY

This report is in response to a request by the House of Representatives,

.Comittee on Interio: and Insular Affairs, to sumarize the Comission's readiness to process an HTGR Construction Permit application. In the report, which is an updated version of a report that we provided to you in February,1986 on the sare subject, we examine current activities and related background for HTGR licer. sing and conclude that, if and when an HTGR Construction Permit Application is received, the Comission will redirect sufficient resources to process it, consistent with other Agency I priorities. l

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II. BACKGROUND i

A. HTGR Regulatory History i 1

The regulatory staff and the ACRS have a long history of HTGR review and licensing activity beginning in the early 1960's with the 40 Mwe Peach Bottom I reactor. The Peach Bottom I reactor was the first HTGR in the U.S., and it operated successfully from 1967 to 1974, when it was shutdown for economic reasons. Following the Peach Bottom experience, the principal events and experiences were the licensing and continuing supervision of the Fort St. Vrain reactor, the Construction Permit reviews of the Sumit and Fulton power plants in the mid 1970's, and the partial review of the standard plant HTGR 1 j (the 1160 Mwe, GASSAR design) in the late 1970's. Also in the mid i 1970's, the regulatory staff completed a review of a conceptual design of a gas cooled fast breeder reactor which did not use HTGR fuel but was of interest to HTGR technology because of component l development issues and the use of natural circulation for emergency l I

core cooling. It should be noted that other than the Peach Bottom I reactor, all of the HTGR designs reviewed by the Comission in the ,

past were of the large plant type using a prestressed concrete reactor vessel. These two features represent major differences from the HTGR concept currently being pursued by DOE and, as such, raise new issues which may require additicnal study, research, and code development prior to licensing. In addition, all but Fort St. Vrain included a containment building in the design. The Fort St. Vrain design was accepted without a conventional containment building because the concrete reactor vessel contained the reactor and prinary cooling system, which is a practice in comon use in European gas cooled reactors.

B. Activities of the Office of Nuclear Regulatory Research NRC's Office of Nuclear Regulatory Research (RES) began contributing to NRC's cumulative HTGR experience in 1974 with the initiation of research on graphites, fuels, high temperature metals, therinal and fiuid-mechanical design, containment design, fission product release and transport, safety instrumentation, seismic and structural design, and safety analyses, including accident code developrsent and validation. Following the GASSAR review, RES became the hRC lead

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4 office for advanced HTGRs, and it also investigated certain technical issues in support of Fort St. Vrain operations. In 1981, RES developed a long range plan for HTGR safety research based upon the reference 2240 Mwt large plant design.

With the recent change in emphasis by DOE from the large plant design to the small modular design, RES suspended its HTGR research activities. This work will be resumed, subject to availability of funds, when our review of the modular HTGR design is sufficiently complete to identify further independent regulatory research needs and when it becomes clear that an application for a construction permit will be submitted. At the present time, we are also reviewing the research which an applicant would need to perform to justify the modular HTGT. design to minimize the research burden on NRC.

C. Fort St. Vrain Experience Experiences with the Fort St. Vrain plant have contributed to HTGR licensing readiness. Significant technical, safety, and licensing information has been developed and is generally well documented.

Performance information developed to date has been generally favorable for the fuel, the prestressed concrete reactor vessel, most I instrumentation and control systems, the steam generators, and the l fuel handling systems. Resolutions and pending resolutions of j performance and licensing concerns over the years have lad to '

important information concerning flow induced motions of the fuel I elements, improved understanding of corrosion and themal stress potentials of structural graphites, improvements in accident analysis anu computer modeling, and better definition of inservice inspection ,

requirements for HTGRs. l 1

A second and equally important benefit to licensing readiness has l oecn the resulting acquisition of practical knowledge of HTGRs by the i regulatory staff members and basic data and techniques by NRC l contractors who have participated in Fort St. Vrain activities over j the years. While the number of staff members involved with Fort St. j Vrain has not been large, they represent a cadre of knowledge ard  ;

experience which could be made available for the licensing of HTGRs l if the priority of this activity were sufficiently high. NRC '

contractors represent an additional source of knowledge and experience that would be available, if needed, for current and anticipated HTGR activities.

i D. Foreign Reactor Experience j Britain Japan, and Germany have strong backgrounds in gas reactor l l

design, operation, and safety analysis which have influenced.

supported, and confirmed domestic HTGR designs and research activities. Information in these foreign programs has generally been available under umbrella agreements and through the HTGR technical comunity.

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Of recent interest is information from West Germasy, which has started and operated a 15 Mwe and a 360 Mwe pebble bed type HTGR and is currently designing a 500 Mwe follow-on plant for future comercialization. Two companies in West Gemany are also developing designs for a modular HTGR concept. The NRC has been and will continue to use available applicable information from these foreign HTGR programs in our review of the U.S. HTGR design.

III. CURRENT ACTIVITIES A. Interactions Between NRC and 00E DOE selected a 350 Mwt modular design c1ncept as the reference HTGR plant to be reviewed by NRC. Meetings and correspondence between NRC and DOE have been underway since mid 19% and have dealt with project planning, familiarization of the NRC st. " with the HTGR concept under development, the identification anc resolution of major safety issues associated with the HTGR concept, a probabilistic risk assessment, and a supporting technology development plan for the HTGR concept. The NRC staff is nearing completion of its review of these issues and submittals and is currently preparing a safety evaluation report (SER) on the conceptual design. The staff plans to issue its 4

SER and a statenent on the licensability cf the conceptual design in FY 88. The technical review done by the staff on the conceptual HTGR design will lay the groundwork and form the basis for our review, if and when an actual application is received. The staff review will also identify any additional areas where the NRC should put resources to be ready for an actual application. Based upon cur review to date, we believe that certain specific issues, unique to the modular HTGR concept, will require further study, research, and code 7

' developrent before we could process a Construction Permit application in a timely fashion and without undue conservatism or burden on the

applicant. Hewever, due to the priority of our responsibility for ensuring the safety of cperating reactors and our current budget constraints, we would plan to initiate work on these new specific issues only when it becomes apparent that a Construction Permit Application will be submitted.

B. Interaction with ACRS The NRC, with DOE and its contractors, have inet several times with the Advisory Comittee on Reactor Safeguards (ACRS) to discuss the advanced HTGR. These meetings were held with both the full comittee and the subcomittee on Advanced Reactors. A letter on the licensability of the conceptual design is expected from the ACRS in FY 88.

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I 6 I C. Technical Assistance and Staffing I i

The staff has contracted with ORNL and BNL for technical assistance in the review of the conceptual HTGR design to develop and utilize l analytical tools for independent calculations, to assess key safety concerns, and to aid in the review of DOE submitted material.

Funding for technical assistance in the review of the HTGR conceptual design has been:

FY 86 450 K FY 87 600 K However, due to budget constraints and the safety research priorities )

associated with operating reactors, HTGR technical assistance work in 1 FY 88 and FY 89 has been reduced. Although we still plan to complete i our SER on the modular HTGR concept in FY 88, it is not likely that funds will be available in FY 88 or FY 89 to complete development of  !

the desired basis or independent analytical tools needed to address I the key safety issues associated with the modular HTGR identified in l our review of the conceptual oesign. Additicnal funds may have to l be redirected from other activities, if and when an HTGR Construction l Permit Application is received.

Currently, the NRC staff assigned to the conceptual design review l consists of a lead senior reactor engineer in RES and part-time specialists in structural and seismic design, thermal and fluid  !

I mechanical design, containment, instrumentation, control and electrical systems, auxiliary systems, probabilistic risk assessment, l safeguards, security, and emergency planning. The total NRC staff effort for each fiscal year from FY 86 to FY 88 has been approximately two professional staff years. NRC staff resources will continue to be applied to complete the review of the conceptual design of the modular HTGR. Review of an HTGR Construction Permit application would require 25-30 Nuclear Reactor Regulation office staff for approximately 2 years. This resource allocation is not in our current budget projections.

D. Regulatory Preparation The NRC will continue to prepare its general regulatory basis for review of advanced reactors in anticipation of future review requests. As part of this preparation, the Connission has issued the following policy statements:

• Policy Statement on Severe Reactor Accidents Regarding Future Designs and Existing Plants published August 8, 1985, 50 FR 32138,

• Policy Statement on Regulation of Advanced Nuclear Power Plants published July 8, 1986, 51 FR 24643, Policy Statement on Nuclear Power Plant Standardization published September 15, 1987, 52 FR 34884.

7 The NRC staff is currently preparing proposed regulations on design certification (10 CFR 52) and guidance on severe accident implementation for future plants. While much of this work is being done to support the on-going reviews of the advanced LWR standard plant applications, it should be generally applicable to HTGRs.

IV. CONCLUSION Our current budget constraints and priority of our responsibility for the safety of operating reactors have limited the resources available to prepare for the processing of an HTGR Construction Permit Application. If and when a Construction Permit Application is received, additioral resources in the areas of licensing review support, code development, and independent research would be redirected from other activities, consistent with Agency priorities, in order to process the Application in a timely fashion without undue conservatism or burden on the applicant.

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