1、An American National StandardPublished by the American Nuclear Society 555 N. Kensington AveLa Grange Park, IL 60526ANSI/ANS-1XFOHDU3RZHU3ODQW5HVSRQVHWRDQ(DUWKTXDNHANSI/ANS-ANSI/ANS-2.23-2016 American National Standard Nuclear Power Plant Response to an Earthquake Secretariat American Nuclear Societ
2、y Prepared by the American Nuclear Society Standards Committee Working Group ANS-2.23 Published by the American Nuclear Society 555 North Kensington Avenue La Grange Park, Illinois 60526 USA Approved April 7, 2016 by the American National Standards Institute, Inc.American National Standard ANSI/ANS-
3、2.23-2016 American National Standard Designation of this document as an American National Standard attests that the principles of openness and due process have been followed in the approval procedure and that a consensus of those directly and materially affected by the standard has been achieved. Th
4、is standard was developed under the procedures of the Standards Committee of the American Nuclear Society; these procedures are accredited by the American National Standards Institute, Inc., as meeting the criteria for American National Standards. The consensus committee that approved the standard w
5、as balanced to ensure that competent, concerned, and varied interests have had an opportunity to participate. An American National Standard is intended to aid industry, consumers, governmental agencies, and general interest groups. Its use is entirely voluntary. The existence of an American National
6、 Standard, in and of itself, does not preclude anyone from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standard. By publication of this standard, the American Nuclear Society does not insure anyone utilizing the standard against liability a
7、llegedly arising from or after its use. The content of this standard reflects acceptable practice at the time of its approval and publication. Changes, if any, occurring through developments in the state of the art, may be considered at the time that the standard is subjected to periodic review. It
8、may be reaffirmed, revised, or withdrawn at any time in accordance with established procedures. Users of this standard are cautioned to determine the validity of copies in their possession and to establish that they are of the latest issue. The American Nuclear Society accepts no responsibility for
9、interpretations of this standard made by any individual or by any ad hoc group of individuals. Inquiries about requirements, recommendations, and/or permissive statements (i.e., “shall,” “should,” and “may,” respectively) should be sent to the Scientific Publications and Standards Department at Soci
10、ety Headquarters. Action will be taken to provide appropriate response in accordance with established procedures that ensure consensus. Comments on this standard are encouraged and should be sent to Society Headquarters. Published by the American Nuclear Society 555 North Kensington Avenue La Grange
11、 Park, Illinois 60526 USA Copyright 2016 by American Nuclear Society. All rights reserved. Any part of this standard may be quoted. Credit lines, should read “Extracted from American National Standard ANSI/ANS-2.23-2016 with permission of the publisher, the American Nuclear Society.” Reproduction pr
12、ohibited under copyright convention unless written permission is granted by the American Nuclear Society. Printed in the United States of America This document is copyright protected. American National Standard ANSI/ANS-2.23-2016 Inquiry Requests Inquiry Format The American Nuclear Society (ANS) Sta
13、ndards Committee will provide responses to inquiries about requirements, recommendations, and/or permissive statements (i.e., “shall,” “should,” and “may,” respectively) in American National Standards that are developed and approved by ANS. Responses to inquiries will be provided according to the Po
14、licy Manual for the ANS Standards Committee. Nonrelevant inquiries or those concerning unrelated subjects will be returned with appropriate explanation. ANS does not develop case interpretations of requirements in a standard that are applicable to a specific design, operation, facility, or other uni
15、que situation only and, therefore, is not intended for generic application. Responses to inquiries on standards are published in ANSs magazine, Nuclear News, and are available publicly on the ANS Web site or by contacting the ANS Scientific Publications and Standards Department. Inquiry requests sha
16、ll include the following: (1) the name, company name if applicable, mailing address, and telephone number of the inquirer; (2) reference to the applicable standard edition, section, paragraph, figure, and/or table; (3) the purpose(s) of the inquiry; (4) the inquiry stated in a clear, concise manner;
17、 (5) a proposed reply, if the inquirer is in a position to offer one. Inquiries should be addressed to: American Nuclear Society ATTN: Scientific Publications and Standards Department 555 N. Kensington Avenue La Grange Park, IL 60526 or standardsans.org American National Standard ANSI/ANS-2.23-2016
18、American National Standard ANSI/ANS-2.23-2016 i Foreword (This foreword is not a part of American National Standard “Nuclear Power Plant Response to an Earthquake,” ANSI/ANS- 2.23-2016.) This standard describes actions a utility should take preceding and immediately following an earthquake felt at a
19、 nuclear power plant site to determine the need to shut the plant down and, if shutdown is required, actions to determine the power plants readiness to restart. The plant operator makes the decision to shut down the nuclear power plant based on U.S. Nuclear Regulatory Commission (NRC) regulations th
20、at require shutdown in the event that the plants design operating basis earthquake (OBE) is exceeded or damage is found during post-earthquake inspections. In some cases shutdown requirements are part of the plants licensing basis (e.g., condition of license, final safety analysis report commitment,
21、 or technical specifications). An industry/NRC consensus criterion that defines OBE exceedance is presented in Electric Power Research Institute (EPRI) report NP-6695, “Guidelines for Nuclear Plant Response to an Earthquake” (1990); ANSI/ANS-2.10-2003 (withdrawn), “Criteria for the Handling and Init
22、ial Evaluation of Records from Nuclear Power Plant Seismic Instrumentation”; and NRC Regulatory Guide 1.166, “Pre-Earthquake Planning and Immediate Nuclear Power Plant Operator Post-earthquake Actions,” issued in 1997. It should be noted that Sec. 4, “Overview of Nuclear Power Plant Response Actions
23、,” in this standard does not specify any requirements or recommendations. Requirements referred to are those that are mandated by long-standing NRC regulations such as the requirement that nuclear power plants have installed seismic instrumentation and that they shut down any time a felt earthquake
24、exceeds the plants OBE. It is only a summary listing of the topics and actions covered in the standard. The sections that specify requirements and recommendations of the standard are Secs. 5 through 9. These sections have been carefully written to implement the use of the American Nuclear Society (A
25、NS) policy to use “shall” and “should” for requirements and recommendations, respectively. Clarifications of this criterion and conditions applicable to its implementation are included in this update of ANSI/ANS-2.23-2002 (R2009). The standard addresses the required sequences of response to an earth
26、quake. It defines pre-earthquake actions, immediate actions, post-shutdown actions, and long-term actions. The findings at each post-earthquake stage indicate the need for, and the level of, any additional effort. The standard specifies that plant personnel perform initial inspections, gather seismi
27、c recordings, and reach decisions on the need for plant shutdown and plant readiness for shutdown. If the plant is shut down, the standard defines procedures for near-term actions by plant operators to determine the earthquake effects, with engineers performing focused inspections and tests to deter
28、mine if structures have sustained significant damage or if operating systems are in any way impaired. The standard then defines actions necessary to establish the readiness of the plant to restart. Finally, the standard provides for long-term, confirmatory evaluations that, in most cases, can be per
29、formed after plant restart. Specifically, the standard specifies actions in five main areas: (1) pre-earthquake preparatory actions; (2) post-earthquake short-term actions; (3) determination of the earthquake damage level, earthquake level, and recommended action level; (4) post-shutdown inspections
30、 and tests; (5) long-term evaluations. In the years following the issuance of ANSI/ANS-2.23-2002 (R2009), a significant amount of experience has been gained on the effects of earthquakes on nuclear power American National Standard ANSI/ANS-2.23-2016 ii plants worldwide, in particular, during events
31、affecting plants in high-seismic-hazard areas such as Japan. International Atomic Energy Agency (IAEA) Safety Reports Series No. 66, “Earthquake Preparedness and Response for Nuclear Power Plants” (2011), documented lessons learned from all significant earthquake ground motions affecting nuclear pow
32、er plants pre-2010. Of interest are three multiunit nuclear power plants in Japan that experienced beyond-design-basis earthquakes over the past several years and one domestic plant (Dominion Energys North Anna plant in Virginia) that recorded an earthquake with measured ground motion accelerations
33、that exceeded its design safe shutdown earthquake level. None of these plants had comprehensive earthquake response procedures; none had implemented pre-earthquake preparations for a beyond-design-basis earthquake; and none had visible damage to safety-related structures, systems, or components. Nev
34、ertheless, many months (in some cases more than a year) and thousands of man-hours of plant inspections and evaluations were spent justifying restart of the plants. A comprehensive earthquake response plan such as the one described herein could have significantly focused and reduced these efforts. B
35、ased on these events and the lessons learned in establishing the effects of the earthquakes on the plants and the actions ultimately undertaken to establish the readiness of the plants to restart, a significant update of EPRI report NP-6695 the technical basis for ANSI/ANS-2.23-2002 (R2009) was prep
36、ared and published in 2013 as EPRI report 3002000720, “Guidelines for Nuclear Plant Response to an Earthquake.” This revised ANSI/ANS-2.23 standard incorporates the significant changes and additions included in EPRI report 3002000720, which serves as the commentary for this standard. It is also cons
37、istent with IAEA Safety Reports Series No. 66. Applicability of the aforementioned documents is specifically limited to nuclear power reactortype plants. This standard might reference documents and other standards that have been superseded or withdrawn at the time the standard is applied. A statemen
38、t has been included in the references section that provides guidance on the use of references. This standard does not incorporate the concepts of generating risk-informed insights, performance-based requirements, or a graded approach to quality assurance. The user is advised that one or more of thes
39、e techniques could enhance the application of this standard. This standard was prepared by the ANS-2.23 Working Group. The following members contributed to this standard: R. Kassawara (Chair), Electric Power Research Institute D. Bhargava, Dominion Energy G. Hardy, Simpson, Gumpertz and Heger E. Hen
40、drixson, Dominion Energy J. Johnson, James J. Johnson and Associates R. Kenneally, Individual R. Kennedy, RPK Structural Mechanics Consulting W. Schmidt, W. Schmidt Consulting American National Standard ANSI/ANS-2.23-2016 iii The Seismic Subcommittee of the Environmental and Siting Consensus Committ
41、ee had the following membership at the time of its approval of this standard: Q. Hossain (Chair), Lawrence Livermore National Laboratory J. Xu (Vice Chair), U.S. Nuclear Regulatory Commission R. Carpenter, U.S. Nuclear Regulatory Commission K. Hanson, AMEC Geomatrix R. Kassawara, Electric Power Rese
42、arch Institute F. Ostadan, Bechtel Corporation J. Savy, Individual I. Wong, URS Corporation The Environmental and Siting Consensus Committee had the following membership at the time of its approval of this standard: C. A. Mazzola (Chair), CB actions to determine the readiness of the plant to resume
43、operation; and those evaluations necessary to verify the long-term integrity of safety-related (SR) and important structures, systems, and components (SSCs). It also includes a consensus definition of operating basis earthquake (OBE) exceedance, beyond which U.S. regulations require plant shutdown.
44、Application of this revised standard provides a comprehensive, balanced plan for the response of a nuclear power plant to an earthquake. This standard does not cover those operator actions that are performed in connection with safe operation and control of the nuclear power plant during and followin
45、g an earthquake. These operations are specified in plant operating procedures, emergency procedures, alarm response procedures, and other conditions of the plants license. Likewise, it does not cover required reporting and communications with the U.S. Nuclear Regulatory Commission (NRC). It is not a
46、pplicable to nuclear facilities other than licensed nuclear power plants. 2 Purpose The purpose of this standard is to specify actions that shall be included in plant-specific procedures that describe actions to be taken in preparation for and response to a felt earthquake at the plant. The objectiv
47、es of these procedures are to determine the following: the effects of the earthquake on the physical condition of the nuclear power plant; whether shutdown of the plant is required, based on observed damage to the plant or because the OBE has been exceeded; the readiness of the plant to shut down if
48、 shutdown is required due to an earthquake; the readiness of the plant to resume operation from a shutdown condition based on physical inspections and tests and the successful completion of operability tests and analytical evaluations, where required, that demonstrate that the limiting conditions fo
49、r operation as defined in the plant technical specifications are met. The combination of the preparatory, short-term, post-shutdown, and long-term actions provides a rational, experience-based approach for determining the real damage potential of a felt and recorded earthquake, a systematic methodology for assessing plant readiness for restart based on physical inspections and tests and on realistic criteria for assuring the long-term integrity of the power plant. These actions also
