ACRS

i 2005-08 Action Plan

Advisory Committee on Reactor Safeguards

U.S. Nuclear Regulatory Commission
The Advisory Committee on Reactor Safeguards (ACRS) was established as a

statutory committee of the Atomic Energy Commission (AEC) by a 1957

amendment to the Atomic Energy Act of 1954. The functions of the Committee are

described in Sections 29 and 1 82b of the Act. The Energy Reorganization Act of

1974 transferred the AEC's licensing functions to the U.S. Nuclear Regulatory

Commission (NRC), and the Committee has continued serving the same advisory

role to the NRC.

The ACRS reports directly to the Commission, providing independent reviews of,

| and advice on, the safety of proposed or existing NRC-licensed reactor facilities and

the adequacy of proposed safety standards. The ACRS reviews powver reactor and fuel

* cycle facility license applications for which the NRC is responsible, as well as the

safety-significant NRC regulations and guidance related to these facilities. On its own

initiative, the ACRS may review certain generic matters or safety-significant nuclear

facility items. The Committee also advises the Commission on safety-significant

, policy issues, and performs other duties as the Commission may request. Upon

request from the U.S. Department of Energy (DOE), the ACRS provides advice on

U.S. Naval reactor designs and hazards associated with the DOE's nuclear activities

and facilities. In addition, upon request, the ACRS provides technical advice to the

Defense Nuclear Facilities Safety Board.

ACRS operations are governed by the FederalAdvisory Committee Act (FACA), which

is implemented through NRC regulations at Title 10, Part 7, of the Code of Federal

Regulations (10 CFR Part 7). ACRS operational practices encourage the public,

industry, state and local governments, and other stakeholders to become involved in

Committee activities.
THE ADVISORY COMMITTEE ON REACTOR SAFEGUARDS

2005-2008 ACTION PLAN, PRIORITIES, AND ACTIVITIES

This plan provides guidance and direction for the Advisory Committee on Reactor Safeguards

(ACRS) for the years 2005-2008 to focus the Committee on the issues that are most important

to the U.S. Nuclear Regulatory Commission (NRC) in carrying out its mission to protect

public health and safety, promote the common defense and security, and protect the environment. It also defines the mission, goals, objectives, and priorities of the ACRS, consistent with

the NRC's Strategic Plan. In addition, this plan provides ACRS as well as the criteria that the

ACRS uses to select issues for review.

SCOPE OF ACRS ACTIVITIES

The Committee reports to and advises the Commission on technical matters related to

nuclear reactor safety and safeguards. The bases of ACRS reviews include Title 10 of the Code

ofFederal Regulations (10 CFR), Parts 20, 21, 26, 50, 51, 52, 54, 55, 70, 72, 73, 76, and 100,

as well as other applicable legislation and regulations. Current regulatory activities that are

within the scope of ACRS responsibilities include license renewal, application of risk-informed

and performance-based regulations, reactor operations, rulemaking, codes and standards,

generic safety issues, research, power uprates, advanced reactor design reviews, facility

application reviews, and other regulatory issues as requested by the Commission. To fulfill its

responsibilities, the ACRS provides a forum for the discussion of technical safety issues by all

affected parties, including the NRC staff, the interested public; the U.S. Department of Energy

(DOE); the NRC's Advisory Committee on Nuclear Waste (ACNW); other Federal agencies;

state, tribal, and local governments; and private, international, and other organizations,

as appropriate.

ACRS MISSION

The mission of the ACRS is to provide the Commission with independent and timely

technical advice on issues of public safety related to nuclear reactors and reactor safeguards.

In so doing, the ACRS supports the NRC in conducting an efficient regulatory program

that enables the Nation to safely use nuclear power for civilian purposes.

ACRS VISION

The ACRS envisages safety regulation of nuclear power plants on the basis of a coherent

set of requirements that are securely founded on science, engineering, and quantitative

risk assessment.

I
I

ACRS OPERATING PRINCIPLES

The ACRS ensures that the priorities of the Commission and its Executive Director for

Operations (EDO) are understood and adequately considered in setting the Committee's agenda. It makes its letters and reports clear and concise. The ACRS continues to believe that early

involvement is, on balance, the best approach for resolving complex issues, and that it allows

the ACRS to provide input when it is most effective and efficient. The ACRS also believes that

the Committee is most effective when it involves itself in the resolution of broad technical

issues. The Committee will continue to maintain its independence as it reviews issues.

OUTCOMES AND COMMITMENTS

The Committee aspires to achieve the following outcomes:

1. Provide useful advice in adequate time for consideration by the Commission in making

regulatory decisions.

2. Alert the Commission to potential challenges that may be averted by taking

interim action.

3. Forewarn the Commission regarding emerging issues that may require action at a

later time.

4. Ensure that the Committee's advice reflects state-of-the-art technology; is practical;

and allows for incorporation into the NRC's technical approaches, regulations,

and guidance.

5. Ensure that the Committee's advice reflects an understanding of inherent risks, and

considers first the need for adequate protection and defense-in-depth, and secondly, the

need to balance risk, cost, and benefit in all of the NRC's decisions.

6. Provide advice that is valued by the Commission, the NRC staff, the DOE, and

the public.

7. Earn the public's trust by providing frank, open advice, and by offering a forum for

public participation in the regulatory process.

8. Assist in resolving conflicts between the NRC and other stakeholders by encouraging

communication and providing a neutral forum for interaction.

To accomplish its mission, the Committee will carry out the following commitments:

1. Focus on nuclear safety.

2. Be responsive to the Commission's needs for technical advice to support

Commission decisions.

2
3. Maintain technical excellence.

4. Focus on risk by asking what is the risk, what are the important contributors to risk,

and what are the uncertainties associated with the risk.

5. Foster an atmosphere of mutual problem solving with the NRC staff.

6. Remain unbiased, be responsive to change, and consider various options and

contingencies.

7. Identify, in advance, those issues that could impact the NRC's ability to achieve

its mission.

8. Keep abreast of international trends and developments that could affect the NRC's

regulatory practices or approaches, and factor international experience into the

Committee's advice, where appropriate.

9. Provide timely public notification of ACRS meetings in order to provide opportunities

for stakeholder participation.

GOALS AND OBJECTIVES

In keeping with its mission, the ACRS has developed the following goals and objectives, which

are consistent with the performance goals in the NRC's Strategic Plan and reflect current regulatory needs:

Goal 1 Provide useful advice to support the Commission in responding to

the evolution of and challenges to the safe use of nuclear power.

Objective I Advise the Commission in a timely fashion on issues of a technical nature

that may impact public health and safrty andprotection of the environment

in the following areas:

implementation of risk-informed and performance-based safety regulations

* the reactor oversight process

* safety issues related to age-related degradation

* research efforts that provide the technical bases for the NRCS

regulatory decisions

* safety issues associated with new nuclear designs

* changes in the nuclear industry

* prioritization and resolution ofgeneric safety issues (GSIs)

* rulemaking and regulatory guidance

* emerging operational issues

technical issues associated with regulatory safeguards

3
Goal 2 Support the NRC in ensuring openness by involving the public in the

ACRS' process of reviewing nuclear power safety and safeguards issues.

Objective I Provide opportunities for meaningfidl public involvement in the regulatory

process by implementing the FederalAdvisory Committee Act (FACA) and by

fostering an open, accessible, and clear, yet independent review process.

Objective 2 Assist the NRC in ensuring that agency decision making is a transparent

process by noting whether agency documentation reviewed by the Committee

is thorough. clear, and readily understandable.

Goal 3 Support the effectiveness, efficiency, and timeliness of NRC operations.

Objective I Advise the NRC on how to increase its reliance on risk insights as a basis for

decision making, including using risk assessment methods for the safe use of

nuclear power. that (1) implements a risk-informed approach, (2) quantifies

and reveals uncertainties, and (3) is consistent across programs, where possible.

Objective 2 Propose approaches that provide a better understanding of the inherent

risks associated with nuclear power and the relationships between safety,

regulations, and cost.

Objective 3 Provide technically sound, realistic, and timely approaches for resolving new

and emerging issues related to the safe operation of nuclear power plants.

Objective 4 Advise the Commission on opportunities for improving agency reviews.

Goal 4 Support the NRC's use of good science in resolving key safety issues.

Objective I Keep abreast of the challenges associated with changing regulatory demands,

as well as the new technologies that are being developed and utilized

throughout the world.

Objective 2 Recommend ways to utilize risk-informed andperformance-based approaches

to ensure effectiveness and efficiency.

Objective 3 Advise the Commission on the effectiveness of the reactor oversight process

with respect to the safety of nuclear power plant operations.

Objective 4 Advise the Commission ofprojected needs for additional NRC technical

capabilities that could enhance the agencys ability to effectively address

safety issues.

Objective 5 Promote the use ofgood science to support staffpositions and regulations.

4
Goal 5 Improve the effectiveness and efficiency of ACRS operations.

Objective I Seek opportunities to increase the value of/ACRS advice to the Commission

and the NRC staff

Objective 2 Maintain innovative and sound business practices thatfocus on outcomes,

andprovide effective toolsfor establishing goals.

Objective 3 Improve and modify operationalproceduresfor reporting on program

accomplishments and matters of accountability.

Objective 4 Enhance the effectiveness of the revietv process by building upon mutually

beneficial relationships with the NRC staff and stakeholders.

PROACTIVE INITIATIVES

In accordance with its charter, the ACRS takes the initiative to proactively investigate issues

that have not yet been presented to the Committee. These issues have emerged as a result of

the broad and far-reaching involvement of the Committee members in their respective areas

of expertise, both domestically and abroad. The following list of proactive initiatives may be

supplemented as new issues arise.

INTERNATIONAL ACTIVITIES

* Quadripartite Hosts 2006

Host the fifth Quadripartite meeting in the United States, as scheduled. The

Quadripartite is a consortium of senior advisory committees on nuclear safety, whose

membership consists of France, Germany, Japan, and the United States (with Sweden and

Switzerland as observers). Meetings are held every 4 years on a rotating basis in the country of the host. The ACRS is scheduled to host the 2006 meeting in the United States.

* Divergence In Regulatory Approaches

Consider, as a part of the Committee's normal reviews, development and treatment of

similar technical issues in other countries, as appropriate.

Maintain an awareness of reactor safety research being conducted in other countries.

ADVANCED REACTOR DESIGNS FOR HYDROGEN PRODUCTION

| Identify potential safety issues for DOE advanced reactor activity to generate hydrogen

from nuclear heat.

* Identify long-term research issues that would require new analytical tools or infrastructure.

5
PROBABILISTIC RISK ASSESSMENT MODEL UNCERTAINTY

* Identify major model uncertainties in Level I and Level 2 probabilistic risk assessments (PRAs).

* Identify methods that have been used or proposed to handle model uncertainty.

* Document examples of model uncertainties that were important in regulatory decisions,

as well as the importance of various phenomenological uncertainties associated with PRAs

and how they have been addressed, with emphasis on Level I and Level 2 PRAs.

POWER UPRATES

* Review the impact of power uprates on the safety of nuclear power plants in light of other

ongoing changes (e.g., aging, longer fuel cycles, higher burnup).

* Review the expanding application of techniques, such as probabilistic fracture mechanics,

to identify and manage margin in systems and components.

MATERIALS

* Review the progress being made in the NRC's "Proactive Materials Degradation

Assessment" program, in response to incidences of corrosion related failures in operating

plants both domestically and abroad.

CRITERIA FOR SELECTING PRIORITY ISSUES

The following criteria are used to identify the priority of issues that the ACRS reviews:

* Does the issue have an immediate impact on nuclear safety?

* Is the issue required by law or regulations?

* Is the issue risk-significant, or does it affect adequate protection of health and safety?

* Are there potential long-term issues requiring continuous attention by the agency?

* Is the issue requested by the Commission?

* Is the issue requested by the EDO?

* Was the issue raised by the public?

* Did the ACRS initiate the review of an issue that may or may not currently be worked on

by the NRC staff?

* Can the issue impact the effectiveness or efficiency of the NRC regulatory process?

6
PRIORITY ISSUES

A list of ACRS priority issues is provided below. This list will be augmented, as necessary, to

support the changing needs of the agency and to deal with significant emerging technical and

safety issues.

LICENSE RENEWAL

* 10 CFR 54.25 requires that each license renewal application be referred to the ACRS for a

review and report. An ACRS review is essential, given the potential safety implications of

extending power operation of a significant number of plants for 20 years beyond their current

licensed terms. ACRS involvement is also important because Congressional and industry interests have made license renewal a high-priority item for the Commission. This places significant

pressure on the NRC staff to expedite the review process, and to reduce demonstration and

documentation requirements. The ACRS has reviewed the improved guidance, and will continue to monitor the implementation of the guidance on individual license renewal applications. ACRS involvement will help in the ongoing development of a standardized license

renewal process. The ACRS will play a valuable role by assuming the following responsibilities:

Participate in the development of revised standardized license renewal processes to ensure

that detailed requirements for license renewal applications are sufficient to provide reasonable assurance that plants will operate safely throughout the period of extended operation.

. I dentify significant issues and focus attention on the ways that these issues are addressed

in individual applications.

Provide to the Commission independent views on contested interpretations of the rule,

such as the issue of credit for existing programs.

Identify issues, as appropriate, that may be outside the narrow confines of the License

Renewal Rule, such as using risk information to further improve the license renesval

process.

i Evaluate the impact of concurrent actions, such as power uprates and/or operational

issues, on licensing renewal commitments and requirements.

The ACRS has performed thorough reviews of the license renewal applications for 27 nuclear

power plants, and has provided timely advice to the Commission. The ACRS has also reviewed

and provided comments on the staff's review process. Six of the reviews were completed in calendar year 2003 and 7 revie vs are scheduled for completion in 2004. The Committee also

provided comments to the staff on the current application review process. The Committee has

completed reviews for the following plants:

Ginna . McGuire 1, 2 . Turkey Point 3,4

* Summer . Catawba 1, 2 . Oconee 1, 2, 3

* Robinson . North Anna 1, 2 . Calvert Cliffs 1, 2

* Fort Calhoun . Surry 1, 2 . Dresden 2, 3

. Saint Lucie 1, 2 . Peach Bottom 3, 4 . Quad Cities 1, 2

7
The ACRS will continue to play a significant role in the license renewal area through the

following activities:

Review each license renewal application.

* Review revisions to license renewal guidance documents (e.g., the NRC's Standard Review

Plan, Regulatory Guides, Generic Aging Lessons Learned (GALL) Report, and 'Industry

Guidelines for Implcmenting the Requirements of the License Renewal Rule" (NEI 95-

10) promulgated by the Nuclear Energy Institute), as necessary.

* Review selected industry topical reports.

* Visit plants, as needed and as resources permit, to gather information regarding the

changes made to the maintenance programs and inspection practices to support extended

plant operations, adequacy of the aging management programs, and other significant

activities related to license renewal.

* Hold meetings to provide a forum for public participation.

* Implement an efficient process to ensure timely completion of the ACRS review of license

renewal applications and related matters.

RISK-INFORMED AND PERFORMANCE-BASED REGULATION

The ACRS has been a strong advocate of the Agency's move toward establishing a riskinformed and performance-based regulatory system. On numerous occasions in the past, the

ACRS encouraged the use of risk information in the regulatory decision-making process, and

provided comments and recommendations regarding the consistent use of probabilistic risk

assessment (PRA), the impact of PRA results and insights on the regulatory system, and the

coherence of the regulatory process. The ACRS has also played a major role in assisting the

NRC staff and providing valuable advice to the Commission for developing a risk-informed

and performance-based regulatory approach. The ACRS has made significant contributions in

this area, including the following:

* performed a participatory review and assisted the staff in developing several regulatory

guides, especially Regulatory Guide 1. 174, "An Approach for Using Probabilistic Risk

Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Current

Licensing Basis," and Regulatory Guide 1.200, "An Approach for Determining the

Technical Adequacy of Probabilistic Risk Assessment Results for Risk-informed Activities"

* reviewed proposed final 10 CFR 50.69, "Risk-Informed Categorization and Treatment of

Structures, Systems, and Components for Nuclear Power Reactors"

* related to large-break loss-of-coolant accidents (LOCAs) and the elicitation process to

determine LOCA frequencies

8
* commented on the NRC staff's draft plan for implementing the Commission's phased

approach to PRA quality

* reviewed the proposed final performance-based, risk-informed revisions to 10 CFR 50.48,

which permits licensees to voluntarily adopt a performance-based approach to satisfy

existing fire protection requirements

* reviewed proposed final risk-informed revision to 10 CFR 50.44, 'Combustible Gas

Control in Containment'

* identified impediments to the increased use of risk-informed regulation

* commented on the role of defense-in-depth in a risk-informed regulatory system

* addressed the treatment of uncertainties in the risk-informed decision-making process

* evaluated the importance measures for risk-informing 10 CFR Part 50

commented on the use of defense-in-depth in risk-informing the activities of the NRC's

Office of Nuclear Material Safety and Safeguards (NMSS)

advised the Commission on the need to better understand the risks associated with lowpower and shutdown operations

The ACRS will continue to add value to the development of a risk-informed and performance-based regulatory framework. To do so, the Committee will review and provide timely

advice to the Commission on the activities associated with the risk-informed and performancebased regulatory system, including the following:

proposed rule to risk-inform the requirements addressing large-break LOCAs, including

the associated NUREG documenting the NRC staff's expert elicitation to determine

LOCA frequencies

proposed American Nuclear Society (ANS), American Society of Mechanical Engineers

(ASME), and National Fire Protection Association (NFPA) standards to be used in support of the Commission's phased approach to PRA quality

proposed NUREG on acceptability of alternate methods and treatments of uncertainties

implementation of regulatory guidance documents associated with risk-informed and the

need for potential revisions to these documents

proposed risk-informed performance indicators

proposed final risk-informed revisions to 10 CFR Part 50, Appendix R, which would

allow for the use of operator manual actions to satisfy current fire protection requirements

9
RULES AND REGULATORY GUIDANCE

10 CFR 2.809 states that when a rule involving nuclear safety matters within the purview

of the ACRS is under development by the NRC staff, the staff will ensure that the ACRS

is given an opportunity to provide advice at appropriate stages and to identify issues to be

considered during rulemaking hearings. A memorandum of understanding between the

ACRS and the EDO delineates the procedures for ACRS participation in the development

of rules and regulatory guidance documents [e.g., Regulatory Guides, Standard Review Plans,

and Regulatory Issue Summary Reports (Generic Letters)]. The ACRS has made significant

contributions in assisting the staff in formulating and/or revising numerous rules and

regulatory guidance documents.

Since its inception, the ACRS has reviewed all safety-significant rules and regulatory guidance

documents that are within its purview, including the General Design Criteria. Recently, the

ACRS played a major role in assisting the staff in developing or revising several important

rules and regulatory guidance documents, including the following:

* proposed amendment to 10 CFR 50.55a, "Codes and Standards," regarding elimination

of the requirement to update inservice inspection and inservice testing programs every

120 months

* proposed rule, regulatory guide, and Standard Review Plan section associated with the use

of an alternative source term at operating reactors

proposed revision to 10 CFR 50.59, "Changes, Tests, and Experiments"

* proposed final revision to 10 CFR 50.65, 'Requirements for Monitoring the Effectiveness

of Maintenance at Nuclear Power Plants"

* proposed rulemaking for shutdown and fuel storage pool operations at nuclear

power plants

* proposed revisions to 10 CFR Parts 50 and 100, and proposed regulatory guide related to

reactor siting criteria

* proposed rule and regulatory guide for fracture toughness requirements for light-water

reactor (LVWR) pressure vessels

proposed rulemaking for reporting reliability and availability information for risk-significant systems and equipment

The ACRS will continue to review and comment on proposed rules and regulatory guidance

documents, as well as revisions to existing rules and guidance documents, including those associated with a risk-informed and performance-based regulatory framework.

10
SAFETY RESEARCH PROGRAM

In a Staff Requirements Memorandum dated September 9, 1997, the Commission requested

that the ACRS provide an annual report to the Commission regarding the NRC's Safety

Research Program, documenting its views on the need, scope, and balance of the research program; whether the research program provides the needed information to the research user

offices; anticipation of research needs; and prioritization and planning of research in the

changing regulatory and technological environment. Since receiving the Commission's request

in 1997, the ACRS has provided five reports (NUREG-1635, Volumes 1 through 5, "Review

and Evaluation of the Nuclear Regulatory Commission Safety Research Program"), which

included valuable advice to the Commission and the staff, as follows:

* NUREG-1635, Vol. 1, dated July 1998, only included ACRS comments and recommendations resulting from the Committee's comprehensive review of the NRC's Safety

Research Program. It included ACRS comments and recommendations on engineering

the reactor safety research program, as well as several specific research activities, including

those related to PRA, human factors, fire protection, severe accidents, containment

integrity, thermal hydraulics, advanced instrumentation and control, reactor fuels, reactor

pressure vessel integrity, and plant aging. The NRC's Office of Nuclear Regulatory

Research (RES) was generally responsive to the ACRS' comments and recommendations.

* In NUREG-1635, Vol. 2, dated July 1999, the ACRS provided additional comments and

recommendations on significant research activities addressed in NUREG-1635, Vol. 1.

This volume emphasized the need to develop PRA models in the areas of severe accidents,

human factors, fire protection, low-power and shutdown operations, and instrumentation

and control systems. Also, the ACRS addressed the need for maintaining an in-house

capability for independent verification of regulatory criteria and resolution of complex

technical issues associated with the integrity of reactor vessel and steam generator tubes.

The Committee also reiterated the need for a strong research program to support the

transition to a risk-informed and performance-based regulatory framework. In general,

the RES agreed to consider the ACRS' comments and recommendations.

* In NUREG-1635, Vol. 3, dated March 2000, the ACRS examined the internal and external contexts that together determine the needs for research and the corresponding

responses of the agency. The ACRS also discussed how the NRC's research has evolved,

and how it may develop in the future. In addition, the Committee presented specific evaluations of research requirements in response to more significant future issues. The

Committee's comments and recommendations were very well received by the Commission

and the RES.

* In NUREG-I635, Vol.4, dated May 2001, ACRS Provided an assessment of the research

programs focusing on the continuing need for various research activities, whether certain

research could or should be done by the industry, and whether the NRC could enhance

efforts to use information developed through cooperative international research activities

instead of performing research in certain areas. The ACRS also attempted to identify

long-range NRC research needs. The RES was generally responsive to the ACRS' comments and recommendations.

11
* In NUREG-1635, Vol. 5, dated June 2003, the ACRS provided its comments and advice

on the RES document entitled "Advanced Reactor Research Infrastructure Assessment,"

which identified gaps in technology that need to be filled prior to the potential certification of a number of new reactor designs. The Committee provided specific advice as to

the direction of the NRC staff work in the areas of generic regulatory framework, human

factors, thermal-hvdraulics, neutronic analysis, severe accident progression and source

term, fuels, and computer capabilities.

• In NUREG-1635, Vol. 6, dated March 2004, the Committee provided its observations

and recommendations concerning the ongoing and proposed research activities. This

report focused on that portion of the NRC research program dealing with the safety of

existing nuclear reactors and advanced light water reactor designs. In its review of the

NRC research activities, the Committee considered the programmatic justification for the

research as wvell as the technical approach and progress of the work. This review attempted

to identify research crucial to the NRC mission. This review also attempted to identify

research activities that have made valuable contributions to the agency mission in the

past, but now have reached the point where additional research is not needed for efficient

and effective safety regulation.

The ACRS plans to continue reviewing the ongoing and proposed research activities as part of

its biennial reports, in which the Committee will provide comments and recommendations to

the Commission on how well the RES program is addressing the agency's needs. The ACRS

also intends to interact with similar advisory committees of other countries, as appropriate and

as resources permit, to remain well informed of the developments in the international research

arena, and to bring those developments to the attention of the Commission, as needed.

The ACRS has also agreed to assist RES in evaluating the effectiveness and utility of the NRC

research programs. This evaluation is mandated by the Government Performance and Results

Act (GPRA) and needs to be in place during fiscal year 2005. The Committee review will

focus on assessing the quality of the NRC research programs. The ACRS plans to provide an

evaluation of the quality of selected research projects to be used in the annual RES performance report and in supporting RES' quality improvement activities. The result of this evaluation will be in the form of a letter report to the Director, RES, providing a quantitative metric

and a narrative evaluation of a selected number of research projects.

GENERIC SAFEYr ISSJES

The ACRS has had a long-standing role in advising the Commission on the staff's prioritization and resolution of GSIs. For several years, the ACRS maintained a separate list of the GSIs

that the Committee identified during its review of significant operating events and applications

for construction permits and operating licenses. Recognizing the additional burden on the staff

in keeping track of the GSls identified by the ACRS and those identified by the staff, the

ACRS and the NRC agreed in the early 1980s to combine the ACRS list of the GSIs with the

list compiled by the NRC staff.

12
The ACRS made significant contributions to the GSI process, including the following:

l played a major role in assisting the staff in developing the methodology for prioritizing

GSIs, which is included in NUREG-0933, "A Prioritization of Generic Safety Issues"

. reviewved the adequacy of the priority rankings (HIGH, MEDIUM, LOW, and DROP)

for more than 800 GSIs (in most cases where the ACRS disagreed, the staff reassessed the

priority rankings and resolved the ACRS concerns)

l reviewed the resolution of essentially all of the unresolved safety issues (USIs) and most of

the GSIs (the staff resolved the ACRS concerns and disagreements regarding the adequacy

of the resolution through additional and/or improved analyses which, in turn, resulted in

a technically sound resolution)

* pushed for the resolution of several GSls that were prioritized about 15 years ago, but still

remained unresolved (subsequently, schedules for resolving these GSIs have been included

in the Chairman's Tasking Memorandum, which is now submitted to Congress every year

and, since the ACRS expressed its concern, several of these GSIs have been resolved, and

the GSI process has been revised)

The ACRS will continue to add value to the GSI process by reviewing the following aspects:

* support staff activities to resolve GSIs in a timely manner, using good science

* adequacy of the proposed priority rankings and resolution of GSIs

* effectiveness of using Management Directive 6.4 and the associated Handbook to

implement the revised GSI resolution process

* validity of the assumptions and analyses used in prioritizing and resolving GSls

* operational events (to determine whether they warrant reassessment of those GSIs that

were previously assigned a "LOW" priority ranking and those that were classified as

"RESOLVED")

* adequacy of the resolution of certain GSIs by the licensees through programs involving

individual plant examination (IPE) and individual plant examination of external events

(IPEEE)

* adequacy of the resolution of the GSIs identified by the Multiple System Responses

Program (MSRP)

* effectiveness of the revised GSI process

13
REACTOR OPERATIONS

The ACRS has made significant contributions in the area of reactor operations by reviewing

safety-significant issues associated with operating plants and several other related matters,

including the following:

continuing review of the reactor oversight process (ROP)

proposed improvements to the inspection and assessment programs, generic communication process, and enforcement policy

differing professional opinion (DPO) issues associated with steam generator tube integrity

* steam generator tube and reactor pressure vessel integrity and steam generator tube repair

limits

* spent fuel pool accident risk

* insights gained from risk-informed pilot applications, including those from pilots for

inservice inspection (ISI), extension of allowed outage times, and online maintenance

* strainer blockage in boiling-water reactors (BWRs)

* reliability of emergency ac power at nuclear power plants

IlE and IPEEE programs

* safeguards issues

* lessons learned from the investigation of significant operating events (e.g., steam generator

tube rupture event and reactor trip and loss of offsite power event at Indian Point Unit 2,

and reactor trip event at Hatch Nuclear Plant)

* improvement of the review process for extended power uprates through a revised standard

review process

highlights of events that occurred at foreign nuclear plants and their associated safety

significance

* power uprate review guidance for licensees and staff

* loss of spent fuel cooling following a loss-of-coolant accident at the Susquehanna

Nuclear Plant

* effectiveness review of NRC's Operating Experience Program

14
The ACRS will continue to make significant contributions to the safe operation of nuclear

plants. To do so, the Committee plans to review several matters in this area, including the

following, and provide valuable and timely advice to the Commission:

use of performance indicators (PIs) in the ROP (to ensure that they provide meaningful

insight into aspects of plant operation that are important to safety)

enhanced NRC training material for inspecting the licensees' corrective action programs

(CAPs)

continuing review of the Significance Determination Processes (SDPs), and its technical

adequacy relative to these processes

a significant operating events

* safety management

materials degradation (cracking, corrosion, etc.), which potentially impact safety and the

economics of nuclear power generation.

* human factors and human reliability analysis models

* reliability and modeling of digital instrumentation and control systems for current

and future plant designs to increase confidence and reduce uncertainty in quantitative

assessments

* issues that led to the shutdown of plants for more than a year, and the associated

corrective action programs

* strainer blockage in pressurized-water reactors (PNWRs)

* risk-based analysis of reactor operating experience and risk-based technical specifications

* pressurized thermal shock (PTS) screening criteria (reevaluation)

* power uprates and applications for extended power uprates of more than 5 percent

(e.g., Vermont Yankee, Hope Creek, and Browns Ferry)

* unanticipated effects of power uprates on BWRs, such as steam dryer degradation

* impact of deregulation on operating plant safety

* impact on safety from changes in nuclear plants (high-burnup fuel, power uprates, plant

life extension, and use of 'best-estimate" or "More-realistic" analyses), and their potential

impact on plant safety

impact from changes in grid reliability and recovery time on station blackout risk

15
In addition, each year, the ACRS will visit one of the NRC's Regional Offices and a plant

in that region, and will meet with the licensee and the regional staff to obtain information

regarding significant issues that are currently being dealt with. Insights gained from these

meetings will be used in the Committee's review of significant regulatory issues, or brought

to the attention of the EDO or the Commission.

TRANSIENT AND ACCIDENT ANALYSIS CODES

Computer codes have become the major tools used to calculate reactor system behavior

during transients and accidents. The codes in use have an ancestry that dates back some 30

years, and a corresponding development process that has not been transparent. As such, the

codes must be carefully compared to relevant experimental data, and used only within the

range of applicability of that data. Given the above, ACRS review of these codes is necessary

for the following reasons:

* The move to risk-informed regulation will result in the use of more realistic codes. Use of

such codes requires a quantitative evaluation of model uncertainties, and the development

of acceptance criteria.

* Code documentation must be acceptable to knowledgeable, impartial observers. Review

of codes to date indicates that documentation needs to be improved. In addition, code

quality must be adequate to support regulatory decisions.

The ACRS has significant interest in the transient and accident analysis codes. As a result,

the Committee has made major contributions in this area by providing formal and informal

comments and recommendations, as follows:

* reviewed several thermal-hydraulic codes and severe accident codes used by the NRC

and/or its contractors (such as RELAP5, TRACE, SCDAP, MELCOR), as well as

industry codes (such as S-RELAP5, TRACG, WGOTHIC, and NOTRUMP)

* identified shortcomings associated with several of these codes

* pointed out the inadequate and incomplete code documentation

* questioned whether the code calculations are sufficiently independent of the noding for

full-scale application

* recommended that the NRC staff should continue to independently verify the validity of

industry codes

* urged the staff to develop documents to guide the content of code submittals, and to

establish procedures for use by the staff in reviewing the industry codes

16
The ACRS is continuing the process of reviewing several codes, including the NRC TRACE

code, General Electric Nuclear Energy (GENE) TRACG, and other codes used to support

advanced reactor designs, as well as the Standard Review Plan Section and Regulatory Guide

that will guide the content of code submittals and include procedures for use by the staff in

reviewing industry codes.

ADVANCED REACTORS

10 CFR 52.53 requires that the ACRS review and report on those portions of standard design

certification applications that concern safety. The Committee has reviewed the General Electric

Nuclear Energy (GENE) application for its U.S. version of the Advanced Boiling-Water

Reactor (ABWR) standard design, the Asea Brown Boveri Combustion Engineering (ABB-CE)

application for the System 80+ standard design, the Westinghouse AP600 design, and the

Westinghouse API000 standard plant design.

The Committee will continue to review the safety aspects of the proposed nuclear power plant

(NPP) designs, and will provide independent views on the technical adequacy of the designs.

In addition, the ACRS is involved in the pre-application review of the Advanced CANDU

Reactor (ACR) 700 and the General Electric Economic and Simplified Boiling Water Reactor

(GE-ESBWR). The Committee will participate in the pre-application reviews of the Gas

Turbine-Modular Helium Reactor (GT-MHR), the International Reactor Innovative and

* Secure (IRIS), and the Simplified Water Reactor (SWR)-1000 designs.

The staff developed and the ACRS reviewed standard RS-002, "Processing Applications for

Early Site Permits," which describes the early site permit (ESP) review process and review criteria. This standard can be used for application review, as applicable. ESP applications have

been submitted by Exelon Generation Company (Exelon), Entergy Operations (Entergy), and

Dominion Generation (Dominion). The ACRS will review these applications and the staff

assessments.

Other ACRS activities include the review of the Construction Inspection Program (CIP) and

the updates to 10 CFR Part 52 rulemaking.

Approval of new advanced reactor designs that are substantially different from existing light

water designs will involve considerably more effort than can be inferred from the AP1000

experience. The evolutionary and passive light water advanced reactor designs are built upon

an existing technology base that was familiar to the NRC staff and the ACRS. New designs

such as the gas-cooled reactors and the ACR-700 will introduce different technologies. A good

example of the difference from the AP1000 is the fuel design. The applicant plans to use existing fuel designs and analytical methods, which have been reviewed and approved by the staff

and the ACRS. For non-LWR designs, the staff and the ACRS will have to consider a large

body of data and other documentation, which in some cases (pebble-bed fuel) are still under

development, to approve the new reactor fuel designs. ACRS interactions with the applicants

and the NRC staff will be extensive and time consuming, as all stakeholders educate themselves about the technologies that are proposed, including the analytical and experimental

bases for demonstrating their safe operation.

17
The ACRS is reviewing a technology-neutral framework document for new plant licensing.

The recent efforts to risk-inform the regulations have provided insights into the value of a topdown approach for the development of a regulatory framework for new plant designs. Such an

approach could facilitate the implementation of performance-based regulations, as well as

ensure a greater degree of coherence among the regulations.

OTHER REGULATORY ACTIVITIES

The ACRS plans to review (or continue reviewing) several other regulatory activities, including

the extended burnup of reactor fuels, use of mixed-oxide (MOX) fuel in commercial lightwater reactors, the MOX fuel fabrication facility, and acceptance criteria for high-burnup fuels.

The ACRS encouraged the NRC's participation in the experimental studies being performed

at the CABRI reactor in France, and plans to follow up on those performed at the NSRR

reactor in Japan. In addition, the ACRS will review reactor pressure vessel embrittlement

issues, control room habitability, decommissioning activities, fire-protection issues, including

credit for manual actions, resolution of associated circuits issues, fire risk requantification,

and the NFPA-805 Standard, human factors, application for uranium enrichment facilities,

safeguards, and transportation of radioactive materials.

SPECIAL PROTECTS

The ACRS has performed an independent review of each major nuclear propulsion plant

(NPP) design proposed by the Naval Reactors (NR) organization of the DOE and the U.S.

Department of Defense (DOD). It is anticipated that additional reviews will be undertaken in

the 2007-2008 time frame. This review was initially requested by the NR organization, and

was subsequently required by a Presidential Directive issued under Section 9 lb of the Atomic

Energy Act.

The ACRS also reviewed the adequacy of the SEAWOLF submarine design in 1994, and

completed review of the safety aspects of the VIRGINIA class submarine during 2002. The

ACRS has added significant value, as follows:

* The ACRS reviewed the safety aspects of the proposed NPP designs, and provided independent views on the adequacy of these designs. Since these designs are classified, they are

not subject to public scrutiny. Consequently, the ACRS' independent evaluation of the

adequacy of these designs provided credibility and aided the NR organization in justifying

the technical adequacy of the designs in front of the U.S. Congress.

• The ACRS' comments and recommendations on the NRTraining Program were very

helpful to the NR organization in enhancing the effectiveness of this program.

* During its review of the Moored Training Ship Demonstration Project in 1987, the

ACRS recommended that the NR organization apply a PRA methodology and severe

accident analysis to the NPP design. Subsequently, the NR organization initiated the

practice of performing a PRA, including severe accident analysis, for all succeeding

NPP designs.

18
At the request of the Commission and the EDO, the ACRS has performed other special

technical reviews:

{ The ACRS, at the request of the EDO, reviewed a differing professional opinion (DPO)

on steam generator tube integrity and provided recommendations to the EDO on

resolution of the DPO.

0 In response to a Commission request, the ACRS completed a technical review of issues

related to spent fuel pool fires and provided recommendations for resolution of the issues.

MEASURES OF SUCCESS

An assessment of the extent to which the goals and objectives of this plan have been achieved

(including the ACRS' effectiveness, efficiency, quality, timeliness, and rate of success in

contributing to the regulatory process) will be addressed in the annual ACRS Operating

Plan and its biennial Self Assessment.

ACRS ACTION PLAN UPDATE

The ACRS will periodically update this plan, as necessary. Revisions to the plan will be

founded on ACRS' recognition of the need to update the plan, input from the Commission,

changes to the NRC's Strategic Plan, changes in the direction of NRC programs, results from

stakeholder surveys and self assessments, external events and factors, and available resources.

ACRS CONTACT

Inquiries should be directed to Maggalean W. Weston, Senior Staff Engineer, ACRS, at

(301) 415-3151 or by email to mww@nrcgov.

19
I

'I

Federal Recycling Program
'I

.I, 

I.