ML090720822
| ML090720822 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 02/02/1977 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| FOIA-2024-000060 NUREG-0053, Suppl. 6 | |
| Download: ML090720822 (20) | |
Text
NUREG-0053 Suppl. No.6 U.
uclear Regulatory Commission Office uelear Reactor Regulation Docket os. 50-338 50-339 L. Korr~JJth,ASLBP 43P~st \\~est Tm'lers (1 )
1977
Available from National Technical Information Service Springfield, Virg1nla l~161 Price: Printed Copy
.50; Microfiche $3.00
SUPPLEMENT NO.6 TO THE SAFETY EVALUATION REPORT BY THE OFFICE OF NUCLEAR REACTOR REGULATION U.S. NUCLEAR REGULATORY COMMISSION IN THE MATTER OF VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION - UNITS 1 AND 2 DOCKET NOS. 50-338 AND 50-339 NUREG-0053 Supplement No. 6 February 2, 1977
TABLE OF CONTENTS PAGE 1.0 INTROOUCTION AND GENERAL DISCUSSION...........................................
1-1 1.1 Introduction............................................................. 1-1 3.0 DESIGN CRITERIA - STRUCTURES, SYSTEMS AND COMPONENTS.......................... 3-1 3.8 Design of Seismic Category I Structures.................................. 3-1 3.8.2 Other Seismic Category I Structures.......*....................... 3-1 5.0 REACTOR COOLANT SySTEM.......................*..*............................. 5-1 5.4 Component and Subsystem Des i gn...........................................
5-1 5.4.2 Steam Generator and" Reactor Coolant Pump Supports................. 5-1
22.0 CONCLUSION
S................................................................... 22-1
APPENDICES PAGE APPENDIX A -
CONTINUATION OF CHRONOLOGY OF RADIOLOGICAL REVIEW.................... A-l i i
1.0 INTRODUCTION
AND GENERAL DISCUSSION 1.1 Introduction On June 4, 1976, the Nuclear Regulatory Commission (Commission) issued its Safety Evaluation Report regarding the application for licenses to operate the North Anna Power Station, Units 1 and 2 (North Anna facility).
The application was filed by the Virginia Electric and Power Company (applicant). Supplement No.1 to the Safety Evaluation Report was issued on June 30, 1976; Supplement No.2 was issued on August 2, 1976; Supplement No.3 was issued on September 15, 1976; Supplement No.4 was issued on December 8, 1976; and Supplement No.5 was issued on December 29, 1976.
Supplement Nos. 1, 2, 3, 4 and 5 to the Safety Evaluation Report documented the resolution of several outstanding items, and summarized the status of the remaining outstanding issues.
The purpose of this supplement is to update our Safety Evaluation Report (and Supplement Nos. 1, 2, 3, 4 and 5) by providing (1) our evaluation of the reanalysis of the spent fuel pool, (2) our response to the ACRS recommendations related to the steam generator supports, and (3) information regarding the current status of matters that are still under review.
Each section of this supplement is numbered the same as the section of the Safety Evaluation Report, and is supplementary to and not in lieu of the discussion in the Safety Evaluation Report and supplements thereto, except where specifically so noted.
Appendix A is a continuation of the chronology of our principal actions related to the processing of the application.
A summary of the remaining outstanding issues is presented in Section 22.0 of this supplement.
1-1
3.8 3.8.2 3.0 DESIGN CRITERIA - STRUCTURES, SYSTEMS AND COMPONENTS Design of Seismic Category I Structures Other Seismic Category I Structures We stated in Section 3.8.2 of Supplement No.3 to the Safety Evaluation Report that the applicant advised us that its review of the structural design computations for the spent fuel pool gave a preliminary indication that the completed spent fuel pool may not satisfy the requirements stated in Section 3.8.1.4 of the Final Safety Analysis Report relative to the allowable stresses under (1) static plus thermal loadings and (2) static plus thermal plus seismic loadings.
We also stated that the applicant was performing an extensive evaluation to fully define the state of stress in the entire spent fuel pool under its design'loadings and that he would submit a report regarding this matter.
In a letter dated November 24, 1976, the applicant submitted the report "Structural Analysis of the Spent Fuel Pool."
The applicant also provided information in response to our request for additional information concerning this matter.
In order to reduce the stresses along the north wall to within the bounds of the allowable criteria, the applicant com~itted to construct a stainless steel lined, reinforced concrete counterfort inside the spent fuel pool against the north wall.
This counterfort will extend from the top of the mat up to the top of the north wall.
We have reviewed the applicant's report and response to our request for additional information and have determined that the method of reanalysis of the spent fuel pool for the loading combinations cited above are acceptable.
The design criteria for the modification, i.e., the addition of the counterfort, ~eet our requirements stated in Section 3.8.4 of the "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants" (NUREG-75/087).
The technical specifications will restrict the storage of spent fuel in the spent fuel pool until the modification is completed.
Our Office of Inspection and Enforcement will verify that this modification is completed in accordance with our requirements before the restriction will be removed.
Therefore, we have concluded that the design of the spent fuel pool is acceptable and therefore consider this matter resolved.
3-1
5.4 5.4.2 5.0 REACTOR COOLANT SYSTEM Component and Subsystem Design Steam Generator and Reactor Coolant Pump Supports In a partial report dated October 26, 1976, prepared by the Advisory Committee on Reactor Safeguards on the North Anna Power Station Units 1 and 2, the Committee stated, in part, the following with respect to the steam generator and reactor coolant pump supports:
"The toughness of the A36 steel was good, but the toughness of the A572 steel was relatively poor at an operating temperature of 80 9 F.
The Applicant, therefore, proposes to operate so that all A572 material is at 180°F or above.
He also plans periodic inspection of the A572 members to the extent that they are accessible.
The Committee believes that increasing the operating temperature is an acceptable solution, but recommends that the operating temperature of the A572 material be substantially above the proposed temperature.
The Committee believes also that it would be prudent not to permit pressurization of the primary system to substantial levels while temperatures of the supports might be well below the operating temperature M, By letters dated November 19 and December 16, 1976, the applicant has committed to employ auxiliary electrical heat to supplement the heat derived from the reactor coolant loop (passive heat sources) as necessary to assure obtaining a 225 degrees Fahrenheit minimum operating temperature for the ASTM A572 material in the support structures.
The applicant further committed that the.temperature of the structures will be elevated to the required minimum operating temperature prior to pressuriza-tion to levels above 1000 pounds per square inch.
Extensive test data were developed during the review of these structures.
Based on our review of these data we conclude that the adoption of the above cited ~easures for supplying supplementary heating to maintain the required temperature is acceptable.
This will result in all materials of which the steam generator and reactor coolant pump supports are fabricated being in or very near the fully ductile condition prior to pressurization of the primary system to a substantial level.
We therefore find the applicant's commitment in this matter acceptable and in consort with the recom-mendation of the Advisory Committee on Reactor Safeguards.
The specific temperature limitations and operating restrictions referenced in the above paragraph will be included in the North Anna Unit Nos. 1 and 2 Technical Specifications.
5-1
We stated in Section 5.4.2 of Supplement No.3 to the Safety Evaluation Report that our evaluation of the repair and nondestructive examination report for the Unit 2 steam generator and reactor coolant pump supports was not complete.
Since then our Office of Inspection and Enforcement has completed its review of this matter and has determined that the repair of the Unit 2 steam generator and reactor coolant pump supports has been completed in accordance with approved procedures.
Accordingly, we conclude that the repair of the steam generator and reactor coolant pump supports for Unit 2 is acceptable and therefore consider this matter resolved.
5-2
22.0 CONCLUSION
S In Section 22.0 of Supplement No.5 to the Safety Evaluation Report, we stated that several items were still outstanding, and that satisfactory resolution of these items would be required before operating licenses for North Anna Power Station, Units 1 and 2 could be issued.
One of these has been resolved, as reported in Section 3.8.2 of this supplement.
The remaining outstanding items which must be resolved and their present status are summarized below.
Resolution of each item will be discussed in a future supplement to the Safety Evaluation Report.
(1)
The design of the system of well points for groundwater control has recently been submitted.
We have reviewed this design and have requested additional information that we have determined necessary for the completion of our review (Section 2.6 of Supplement No.2 to the Safety Evaluation Report).
(2)
The applicant must provide additional information regarding the dynamic analyses of the effects of a postulated loss-of-coolant accident on fuel elements (Section 4.2.4 of the Safety Evaluation Report).
(3)
The applicant has provided additional information on the seismic and environ-mental qualification of seismic Category I instrumentation and electrical equipment.
We have reviewed this information and have requested additional information that we have determined necessary for the completion of our review (Section 3.10 of the Safety Evaluation Report and Section 3.10 of Supplement No.3 to the Safety Evaluation Report).
(4)
The applicant has provided additional information on overpressurization of the reactor coolant system when in a water-solid condition.
We have reviewed this information and have requested additional information that we have determined necessary for the completion of our review (Section 5.2.8 of Supplement No.2 to the Safety Evaluation Report).
Subject to satisfactory resolution of the outstanding matters described above, the conclusions as stated in Section 22.0 of the North Anna Power Station, Units 1 and 2 Safety Evaluation Report remain unchanged.
22-1
December 16, 1976 December 16, 1976 December 22, 1976 December 23, 1976 December 27, 1976 December 28, 1976 December 29, 1976 December 29, 1976 December 30, 1976 January 4, 1977 January 4, 1977 APPENDIX A CONTINUATION OF CHRONOLOGY OF RADIOLOGICAL REVIEW VEPCO letter transmitting information concerning potential effects of a LOCA on reactor fuel for North Anna, Units 1 and 2, Staff Comment 5.78.
VEPCO requested withholding as propri etary.
VEPCO ietter concerning the minimum operating temperature of the beams of ASTM A572 material in the North Anna supports.
VEPCO letter transmitting Amendment No. 60 to the FSAR.
This amendment consists of the substitution, deletion and addition of pages.
VEPCO letter transmitting a list of the instrumentation associated with the reactor coolant pumps.
Division of Project Management letter requesting additional information on Structural Analysis of Spent Fuel Pool.
Westinghouse letter requesting a 30-day extension for justification to withhold document AW-76-28.
Division of Project t1anagement letter to the ACRS transmitting 20 copies of Supplement No. 5 to the North Anna Safety Evaluation Report.
Issuance of Safety Evaluation Supplement No. 5 to the North Anna Safety Evaluation Report.
Decision issued by the ASLAB.
The ASLAB affirmed the June 9, 1976 order allowing Sun Ship to intervene.
Meeting of NRC staff concerning the January 1976 ACRS meetings for the North Anna Power Station, Units 1 and 2.
VEPCO letter transmitting additional information requested by the NRC staff in the November 15, 1976 meeting.
A-l
January 4, 1977 January 4, 1977 January 4, 1977 Janua ry 4, 1977 January 4, 1977 January 7, 1977 January 7, 1977 January 10, 1977 January 12, 1977 January 12, 1977 January 14, 1977 January 14, 1977 January 17, 1977 January 19, 1977 VEPCO letter advising that the response to Staff Comment 3.73 will appear in the next amendment and is transmitted herewith.
VEPCO letter concerning Section 9.5 of the North Anna, Units 1 and 2 FSAR.
VEPCO letter transmitting the initial draft of the Technical Specifications for North Anna, Units 1 and 2.
VEPCO letter transmitting additional information concerning potential effects of a LOCA on the control rods.
VEPCO transmits a Certificate of Service for Amendment No. 60 to the FSAR.
Di vi s i on of Project t1anagement 1 etter transmitti ng Suppl ement No.5 to the Safety Evaluation Report to applicant and service list.
VEPCO letter requesting an extension of construction comple-tion dates for Units 1 and 2, CPPR-77 and CPPR-78.
VEPCO letter transmitting results of 1976's sampling of groundwater ~c~it8ring.
Summary of January 5, 1977 ACRS Subcommittee r1eeting and January 6, 1977 ACRS Commi ttee t1eeti ng.
Division of Project Management letter requesting Additional Information for 3.0, 3.73 and 3.74.
Division of Project Management letter concerning the extension of time for justification of proprietary information on North Anna to February 10, 1977.
Westinghouse Electric Corporation letter providing a supple-mental afftdavit for AW-76-28 submitted on July 19, 1976 concerninq the evaluation of seismic and LOCA effects on a fuel assembly for North Anna, Units 1 & 2.
ACRS issues its Report on North Anna Power Station, Units 1 and 2.
Division of Project Management letter requesting additional information concerning the Reactor Coolant System.
A-2
January 19, 1977 January 25, 1977 January 26, 1977 Division of Project Management letter transmitting a copy of the ACRS Report on North Anna, Units 1 & 2.
Division of Project Management letter concerning Fire Protection Evaluation for North Anna, Units 1 & 2.
Division of Project Management letter concerning Extension of Construction Completion Dates for Units 1 and 2.
A-3
<>U.S. GOVERNMENT PRINTING OFFICE: 1977 720-132/1 1-3