Resolution of Generic Safety Issues: Task CH1: Administrative Controls and Operational Practices (Rev. 1) ( NUREG-0933, Main Report with Supplements 1–35 )
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This task, outlined in Chapter 1 of NUREG-1251,1174 called for the staff to review the administrative controls over plant operations in the U.S. to determine if adequate controls are in place to maintain plant conditions within the safe operating envelope. This review will include an assessment of procedural adequacy and compliance, approval of tests, bypassing of safety systems, availability of engineered safety features (ESF), operating staff attitudes toward safety, management systems, and accident management.
ITEM CH1.1: ADMINISTRATIVE CONTROLS TO ENSURE THAT PROCEDURES ARE FOLLOWED AND THAT PROCEDURES ARE ADEQUATE
This item consists of two recommendations that are evaluated separately below.
ITEM CH1.1A: SYMPTOM-BASED EOPs
DESCRIPTION
During the Chernobyl event, serious operational errors aggravated the emergency situation that existed and were considered to be a major contributor to the disastrous consequences that ensued. Although design and operational control protections at U.S. reactors provide assurance against the chain of events that occurred at Chernobyl, the Chernobyl experience suggests that closer attention should be paid to effective emergency procedures and the ability of operators to use them. Symptom-based EOPs and their full implementation are a key part of the necessary preparedness for effective management of emergencies. Recent audits by the NRC have identified deficiencies in the implementation of the new symptom-based EOPs. In addition, NRC examinations have identified the need for additional training in the use of these EOPs. The staff has undertaken an accelerated inspection program of EOPs which is aimed at evaluating their technical correctness and their ability to be physically and correctly carried out. This program consists of a four-team effort encompassing four units of each of the four reactor vendor types. Possible regulatory action to upgrade this program or possible further study of any inconclusive results will be considered following staff review of the results of this inspection program.
Staff stated in the Supplement to NUREG-0933 published in 1989 that this issue was directed toward integration of Chernobyl lessons into the staff's EOP effort and was expected to increase the staff's knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, it was considered to be a licensing issue.
CONCLUSION
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
ITEM CH1.1B: PROCEDURE VIOLATIONS
DESCRIPTION
Procedure violations at nuclear power plants are committed by licensed and auxiliary operators, plant technicians, maintenance personnel, and contractors. While the NRC believes that these violations are infrequent and only rarely occur with the knowledge that they are being committed, the exact nature and extent of these violations and their consequences are basically unknown. At Chernobyl, serious procedure violations were a key factor in the cause of the accident. This issue called for the staff to identify procedure violations committed at nuclear power plants, evaluate their consequences, and, if warranted, recommend options for regulatory actions to minimize future violations. The staff will focus initially on those procedure violations associated with reactor scrams or scram signals and will address the following:
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Staff stated in the Supplement to NUREG-0933 published in 1989 that in pursuing this issue, the staff was expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue was considered to be a licensing issue.
CONCLUSION
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
ITEM CH1.2: APPROVAL OF TESTS AND OTHER UNUSUAL OPERATIONS
This item consists of two recommendations that are evaluated separately below.
ITEM CH1.2A: TEST, CHANGE, AND EXPERIMENT REVIEW GUIDELINES
DESCRIPTION
Planned tests and experiments not described in licensees' SARs and changes to facilities and procedures described in these reports are required to be evaluated beforehand by licensees, in accordance with 10 CFR 50.59, to assure their safety and that the NRC is afforded the opportunity to review them where appropriate. Thousands of these reviews are successfully conducted by licensees each year; however, in some instances, these reviews have not been adequate. As a result, the NRC was not always afforded the opportunity to review those tests, experiments, and changes that involved an unreviewed safety question before they were performed. Without appropriate reviews by licensees and the NRC, tests could be performed without adequate safety provisions or some safety features could be unacceptably altered, a condition that could remain undetected for lengthy periods. The Chernobyl accident occurred during a test and the lack of adequate planning review, preparation, and implementation of the test emphasizes the need for attention to this issue.
The need for review guidance for tests, changes, and experiments was identified before the Chernobyl accident and is being addressed by a NUMARC/NSAC Working Group and by the NRC Technical Specifications Branch in the Technical Specifications Improvement Program (TSIP). Staff stated in the Supplement to NUREG-0933 published in 1989 that the NUMARC/NSAC Working Group would develop draft criteria and guidelines and provide them to the industry and the NRC for review and comment. When acceptable to the Working Group and a consensus of the industry agreed, the NRC would review the guidance document which would be made available to all licensees and might be supplemented if necessary to permit NRC endorsement. The industry and the NRC would use the guidance in their review of tests, experiments, and changes required by 10 CFR 50.59. The scope of this issue was limited to coordination to assure appropriate introduction of Chernobyl lessons into the ongoing program.
In pursuing this issue, the staff was expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue was considered to be a licensing issue.
CONCLUSION
An NRC Working Group consisting of seven members and two ad hoc members was formed in July 1987 to coordinate with NUMARC/NSAC the development of guidance for 10 CFR 50.59 reviews including tests, experiments, and changes and to recommend an endorsable product to NRC management. Regional coordinators were named to interact with the Working Group and to assist it in various requests, including comment requests on NUMARC/NSAC draft documents. Two drafts of the NUMARC/NSAC Working Group "10 CFR 50.59 Guidance Document" were forwarded to the NRC for comment.
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
ITEM CH1.2B: NRC TESTING REQUIREMENTS
DESCRIPTION
There is a potential for human error when conducting tests to assess equipment capabilities. This potential represents a risk to plant safety which can vary in severity depending both on the nature of the tests and the circumstances associated with them. Tradeoffs between the risks of not testing or of testing at a lesser frequency and the risks associated with such testing have not always been assessed. The Chernobyl accident occurred when the unit was used for a test. This issue called for the staff to determine if there are any post-startup equipment tests whose conduct presents a sufficient potential impact on plant safety to suggest either their modification, reduced frequency, or elimination.
Staff stated in the Supplement to NUREG-0933 published in 1989 that the staff would review NRC-required post-initial-startup equipment tests at nuclear power plants to identify those tests where human error could result in risks to plant safety. For this issue, "risk to plant safety" was defined as a reactor scram or scram signal, a challenge to ESF, unanticipated releases of radioactive materials, or any other evident unacceptable plant condition. The staff would quantify the potential risk for such tests and recommend a revised testing requirement for those with excessive risk. In resolving this issue, the staff will:
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In pursuing this issue, the staff was expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue was considered to be a licensing issue.
CONCLUSION
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
ITEM CH1.3: BYPASSING SAFETY SYSTEMS
This item consists of one recommendation that is evaluated below.
ITEM 1.3A: REVISE REGULATORY GUIDE 1.47
DESCRIPTION
The bypassing of safety functions by inadvertently bypassing redundant divisions of safety systems for test or maintenance purposes should be prevented. Safety system bypass was a key part of the cause of the Chernobyl accident. This issue called for the staff to recognize the lessons of Chernobyl in ongoing work to revise and improve Regulatory Guide 1.47.150 Staff stated in the Supplement to NUREG-0933 published in 1989 that the scope of this issue included improved methods for indication of individual division bypass conditions and improved administrative controls over individual division bypasses. Completion of this issue would also resolve TMI Action Plan48 Item I.D.3, "Safety System Status Monitoring." In revising Regulatory Guide 1.47,150 the staff would: (a) evaluate the implications of bypassing safety systems; (b) recommend improved procedures and methods to prevent inadvertent bypassing of safety functions during test or maintenance; and (c) prepare revised Regulatory Guide 1.47 to reflect (a) and (b).
In pursuing this issue, the staff was expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue was considered to be a licensing issue.
CONCLUSION
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
ITEM CH1.4: AVAILABILITY OF ENGINEERED SAFETY FEATURES
This item consists of three recommendations that are evaluated separately below.
ITEM CH1.4A: ENGINEERED SAFETY FEATURE AVAILABILITY
DESCRIPTION
ESF equipment needed to mitigate DBAs and transients currently have operability requirements in the TS to assure their availability for all modes of operation. In some instances, all of this equipment has not been evaluated in light of the need for its availability for plant shutdown modes. This issue called for the staff to evaluate and specify operability (availability) requirements for those ESF and support systems needed to mitigate DBAs and transients.
The issue will be addressed in the TSIP and is part of an overall program to ensure that the Owners' Groups and individual licensees specify the appropriate plant status modes for ESF equipment. In some of the older TS, mode requirements for operability may not be specified for other than the power operating mode. In the rewrite of the "Bases" sections of the TS, the reasons for LCOs will be included. Where the mode is currently absent or is inappropriately specified, the Bases will be clarified to identify required ESF equipment for each operational condition. However, ESF-required availability will only be addressed with respect to DBAs and transients and initial conditions (modes) currently analyzed in FSARs.
Reactor-vendor-based Owners' Groups will be permitted to remove those specifications in current STS that do not meet Commission criteria for what should be included in the TS. Requirements remaining in the TS will be rewritten and improved. Each rewritten and improved TS must have a Bases section that not only explains why a TS is needed, but also explains the plant conditions for which it is needed. This need will be evaluated for all of the operating modes of the plants.
Licensees will be encouraged to convert to the new STS and conduct similar upgrades for plant-unique specifications that meet the NRC criteria for the TS. These plant upgrades will be done on a voluntary basis. Those licensees participating will have appropriate ESF operability requirements specified for plant conditions where equipment could be needed for accident mitigative purposes. Upgraded plant-unique TS will also be evaluated. If significant ESF availability disparities are disclosed in this upgrade, they will be recommended for backfit on non-program participants' TS as the need arises.
In pursuing this issue, the staff is expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue is considered to be a licensing issue.
CONCLUSION
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
ITEM CH1.4B: TECHNICAL SPECIFICATIONS BASES
DESCRIPTION
Current TS Bases do not always provide a clear and comprehensive discussion linking specific requirements to the safety analysis assumptions they are derived from. This can result in operators not being as aware as possible of the safety significance of certain types of TS violations, an issue that may have had a counterpart at Chernobyl. It can also result in TS changes being proposed without adequate consideration of all the relevant safety issues. This issue called for the staff to develop an upgraded set of Bases for the STS to provide a clearer link between requirements and the safety analysis. The upgraded standard Bases will be made available to individual licensees for the purpose of adapting them to their plants as part of a voluntary industry-wide program to improve the TS.
It is planned that a separate set of upgraded standard Bases will be developed for each LWR design. The upgraded Bases will be developed as part of an ongoing joint NRC/Industry Technical Specifications Improvement Program (see SECY-86-310) that was initiated prior to the Chernobyl event. This is a program whereby the industry/utility owners' groups will completely rewrite the STS (including the Bases), making improvements in both format and content.
Once the new STS are developed, it is expected that most utilities will voluntarily elect to adopt them for their plants. Any decision to require an individual licensee to convert to the new STS will be made in accordance with the Backfit Rule (10 CFR 50.109). This issue is limited to the introduction of Chernobyl lessons into the staff's ongoing work and no separate work beyond that already started under the TSIP is planned. The Bases rewrite part of the Improvement Program will be comprehensive. A clear one-to-one relationship between TS requirements and the safety analysis will be documented in a carefully formatted Bases section for each TS. Separate Bases subsections will be written to address separate parts (i.e., LCOs, Action Statements, and Surveillance Requirements) of each plant's TS.
In pursuing this issue, the staff is expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue is considered to be a licensing issue.
CONCLUSION
As reported in the Supplement to NUREG-0933 published in 1989, no incremental work attributable to Chernobyl lessons would be necessary to complete this issue. The only additional resources necessary would be those required to report progress against the Chernobyl Follow-up Research Plan and write a closeout report.
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
ITEM CH1.4C: LOW POWER AND SHUTDOWN
DESCRIPTION
The Chernobyl event occurred when the unit was in a state of low power. In contrast, most regulatory attention and virtually all PRAs have focused on a state of full power operation. This issue called for the staff to perform an analysis of the core damage frequency and risk associated with a plant being in a state of low power or shutdown. The staff will examine the probabilistic risk from potential accidents initiated during shutdown and low power conditions at the Surry nuclear power plant.
In pursuing this issue, the staff is expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue is considered to be a licensing issue.
CONCLUSION
As reported in the Supplement to NUREG-0933 published in 1989, the contract work on this task was being done as a part of the Accident Sequence Evaluation Program. Potential reactivity accident sequences that could originate at low or zero power were included in the scope of Item CH2.1A, "Reactivity Transients," the results of which might provide input to this issue.
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
ITEM CH1.5: OPERATING STAFF ATTITUDES TOWARD SAFETY
DESCRIPTION
A significant aspect of the Chernobyl accident involved operator decisions and actions that reflected an apparent loss of the sense of vigilance toward safety and ultimately led to operators allowing operations outside the safe operating envelope. Some potential causes of this unacceptable attitude were: (1) pressure on the operators to complete a test during the reactor shutdown as the next opportunity would have been more than a year away; (2) test delay may have aggravated operator impatience and contributed to a "mindset" that led to imprudent safety actions; (3) operators, being so intent on establishing acceptable power level for the test, may have ignored the unstable state of the reactor; and (4) a clear failure to appreciate the basic reactor physics of the RBMK reactor. The accident raised the question whether licensed operators, senior operators, and other staff at nuclear power plants in the U.S. have and maintain an acceptable level of vigilance toward safety when operating commercial nuclear power plants.
In pursuing this issue, the staff increased its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Thus, the issue was considered to be a licensing issue.
CONCLUSION
The staff believes that safeguards against unacceptable operator and plant personnel attitudes toward safety are adequate. This conclusion is based on the significant increase in the quality of training, industry initiatives in accrediting training programs, and regulatory and industry oversight inspections. Thus, this Licensing Issue has been resolved.
ITEM CH1.6: MANAGEMENT SYSTEMS
This item consists of one recommendation that is evaluated below.
ITEM CH1.6A: ASSESSMENT OF NRC REQUIREMENTS ON MANAGEMENT
DESCRIPTION
Management oversight at all levels must be effective to ensure that tests, maintenance, and operations are conducted safely and that NRC requirements are enforced. The NRC is developing improved methods of monitoring licensee management performance to give early warning of management problems and to initiate enforcement mechanisms. It is also important to ensure that the monitoring and evaluation of management systems consider management capability to handle emergencies and the immediate effects of an accident. Issues of importance include management measures to ensure the availability of personnel capable of handling emergencies, planning for the operation of plant controls and systems with severe core damage, and plant staff training for operation under severe emergency conditions. At the same time, it is important that NRC-imposed requirements on management be reasonable and without excessive burdens that could divert from critical responsibilities. Management failure to recognize and respond appropriately to hazardous conditions was a major factor in the Chernobyl accident. This issue called for the staff to ensure that NRC research programs involving the review or evaluation of utility management include the management issues arising from the Chernobyl event, with particular attention to matters important to safety and to avoidance of excessive burdens that could divert that attention.
The staff will coordinate activities of the following research programs that focus on the performance of utility management to ensure that the concerns of this issue are being addressed cohesively: (1) Management/Organization Influence on Human Error Rates; and (2) Programmatic Performance Indicators. Activities of any new research programs in this area, e.g., Severe Accident Management, will be coordinated for the same purpose. The staff will also coordinate the development of the following evaluation techniques:
(a) Management capability to handle severe accidents of the Chernobyl scale; (b) Management measures requiring the availability of personnel capable of handling emergencies of the type experienced at Chernobyl; (c) Management programs for training personnel to handle emergencies; and (d) Management plans for the operation of plant controls and systems to cope with severe core damage. Coordination will be extended to the following identified user needs as these needs are translated into research programs: (1) Operator Performance Under Stress of Emergency Operations; and (2) Severe Accident Management.
In pursuing this issue, the staff is expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue is considered to be a licensing issue.
CONCLUSION
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
ITEM CH1.7: ACCIDENT MANGEMENT
This item consists of one recommendation that is evaluated below.
ITEM CH1.7A: ACCIDENT MANAGEMENT
DESCRIPTION
The consideration of severe accidents in current symptom-based procedures typically does not go beyond the area of inadequate core cooling. This issue called for the staff to coordinate NRC research activities and programs dealing with severe accident management to ensure the appropriate incorporation of insights gained from the Chernobyl event. This may involve the review of severe accident management programs that may be implemented at existing nuclear power plants. The staff will: (a) assist in scoping the training, organization and habitability elements of new research programs addressing severe accident management to incorporate the Chernobyl lessons learned; (b) review ongoing NRC severe accident management programs and recommend modifications as needed to include the insights gained from the Chernobyl event; and (c) participate in NRC reviews of individual plant severe accident management programs and determine the extent to which these programs have taken advantage of the insights gained from the Chernobyl event.
In pursuing this issue, the staff is expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue is considered to be a licensing issue.
CONCLUSION
As a part of the improvements to NUREG-0933, the NRC staff clarified in SECY-11-0101, "Summary of Activities Related to Generic Issues Program," dated July 26, 2011,1967 that the Generic Issues Program will not pursue any further actions toward resolution of licensing and regulatory impact issues. Because licensing and regulatory impact issues are not safety issues by the classification guidance in the legacy Generic Issues Program, these issues do not meet at least one of the Generic Issues Program screening criteria and do not warrant further processing in accordance with Management Directive 6.4, "Generic Issues Program," dated November 17, 2009.1858 Therefore, this issue will not be pursued any further in the Generic Issues Program.
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