488th Meeting - December 6, 2001

                Official Transcript of Proceedings


Title:                    Advisory Committee on Reactor Safeguards
                               488th Meeting

Docket Number:  (not applicable)

Location:                 Rockville, Maryland

Date:                     Thursday, December 6, 2001

Work Order No.: NRC-132                                Pages 1-98

                   NEAL R. GROSS AND CO., INC.
                 Court Reporters and Transcribers
                  1323 Rhode Island Avenue, N.W.
                     Washington, D.C.  20005
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                                 + + + + +
                            488TH ACRS MEETING
                                 + + + + +
                             DECEMBER 6, 2001
                                 + + + + +
                            ROCKVILLE, MARYLAND
                                 + + + + + 
                       The Advisory Meeting met at the Nuclear 
           Regulatory Commission, Two White Flint North, Room 
           2B3, 11545 Rockville Pike, at 8:30 a.m., Dr. George E.
           Apostolakis, Chairman, presiding.
                 DR. GEORGE E. APOSTOLAKIS, Chairman
                 DR. MARIO V. BONACA, Vice Chairman
                 DR. DANA A. POWERS, Member
                 DR. STEPHEN L. ROSEN, Member
                 DR. WILLIAM J. SHACK, Member
                 DR. THOMAS S. KRESS, Member at Large
                 DR. JOHN D. SIEBER, Member
                 DR. F. PETER FORD, Member
                 DR. GRAHAM  B. WALLIS, Member.           ACRS STAFF PRESENT:
                 DR. NOEL F. DUDLEY, Executive Director
                 HOWARD J. LARSON, ACRS
                 SAM DURAISWAMY, Designated Federal Official
           .                                 I-N-D-E-X
                       AGENDA ITEM                         PAGE
           Opening Remarks by ACRS Chairman . . . . . . . . . 4
           NEI 97-06 Steam Generator Program Guidelines . . .10
           Proposed Rulemaking for Risk-Informed. . . . . . .75
                 Revisions to 10 CFR 50.44
           Adjourn. . . . . . . . . . . . . . . . . . . . . .98
           .                           P-R-O-C-E-E-D-I-N-G-S
                                                    (8:30 a.m.)
                       VICE CHAIRMAN BONACA:  Good morning.  The
           meeting will now come to order.  This is the second
           day of the 488th meeting of the Advisory Committee on
           Reactor Safeguards.  
                       During today's meeting the Committee will
           consider the following: NEI 97-06, Steam Generator
           Program Guidelines; Proposed Rulemaking for Risk-
           Informed Revisions to 10 CFR 50-44; Standards for
           Combustible Gas Control System in Light-Water Cooled
           Power Reactors; ACRS/ACNW Office Retreat; and Proposed
           ACRS Reports.
                       This meeting is being conducted in
           accordance with the provisions of the Federal Advisory
           Committee Act.  Mr. Sam Duraiswamy is the designated
           Federal official for the initial portion of the
                       We have received written comments from Mr.
           Bob Christie of Performance Technology regarding
           proposed rule-making for Risk-Informed Revisions to 10
           CFR 50.44.
                       You all have received a copy of Mr.
           Christie's statements, and this document would be made
           part of the record of this meeting.  We have received
           no requests for time to make oral statements from
           members of the public regarding today's sessions.  
                       A transcript of portions of the meeting is
           being kept, and it is requested that the speakers use
           one of the microphones, and identify themselves, and
           speak with sufficient clarity and volume so that they
           can be readily heard.
                       Before we move to our agenda, I would like
           to make an announcement.  I am sorry to announce that
           Jack Sorensen's term with the ACRS expires on December
           31st, 2001.  So, Jack will be leaving us.  We will
           miss him, because Jack over the past four years has
           made significant contributions to the ACRS.
                       He has done work for the ACRS in a number
           of areas, including defense in depth, risk informed
           regulations, safety culture, and human performance
                       The latest paper that he developed for us
           was regarding risk-informing the GDCs, and we thank
           him for all his contributions.  Fortunately, Jack is
           not going to move far away.  He will be working with
           the Office of Nuclear Materials Safety and Safeguards,
           which is in this building.  
                       So we will have hopefully many
           opportunities to meet again with Jack over the next
           year or whatever period that you have with that
                       I want to especially thank you from George
           Apostolakis.  He really wanted to be here and
           recognize you, but unfortunately had a conflict, and
           I am sure that he will be sitting down with you and
           thank you personally.  
                       I don't know if you have any statement
           that you would like to make.
                       DR. SORENSEN:  Well, thank you for the
           acknowledgement.  I have thoroughly enjoyed the four
           years that I have spent here.  I certainly have had
           experiences that I would not have had otherwise, like
           writing a joint paper with Dana Powers, and Tom Kress,
           and George Apostolakis, and a number of other
                       I do thank you for the opportunity to work
           with you, and I hope that I will see you periodically
           over the next year or so.
                       VICE CHAIRMAN BONACA:  Okay.  With that,
           I think we will move to our agenda, and the first item
           on the agenda is NEI 97-06, Steam Generator Program
           Guidelines.  I will now turn to the Chairman of the
           Subcommittee, Dr. Peter Ford.
                       DR. FORD:  Thank you, Mario.  The last
           time the full ACRS subcommittee was briefed on the
           industry steam generator program guidelines, and that
           is NEI 97-06, was in April of 1999.
                       Sine then, there has been a hiatus in the
           staff's review to the emerging issues associated with
           Indian Point, Unit 2, tube failure event, and a
           differing professional opinion.  The staff's planned
           actions in response to the steam generator integrity
           issues  have been reflected in the Agency's steam
           generator action plan, in which we had a part.
                       In the last six months there have been a
           significant number of constructive discussions between
           the staff and NEI at all management levels.  These
           discussions centered around, first, the staff's
           comments on EPRI guidelines referenced in NEI 97-06,
           steam generator program guidelines; and that was dated
           January of 2001.
                       And, secondly, the NEI generator license
           change package, dated February of 2000, which
           addresses irregularity aspects of changing the
           technical specifications.  
                       There is now substantial agreement between
           the staff and NEI.  The staff believes that the
           revised generic license change package can be
           submitted that would offer sufficient regulatory
                       Some issues have to be resolved.  For
           instance, management's inspection intervals need to be
           justified, and suitable language needs to be included
           in the administrative technical specifications in a
           change package to provide necessary regulatory
           controls on inspection intervals.
                       However, these issues are not seen as
           show-stoppers.  Presentations were made to the
           Materials and Metallurgy Subcommittee on September
           26th, and again on November 29th.  
                       Given that the NEI plans to submit a
           revised generic license change package in mid-2002,
           and that the staff plans to review and approve the
           change package by the end of 2002, we thought it was
           timely that a full ACRS committee should be exposed to
           the regulatory approach and to the remaining technical
           issues, so as to offer advice to the staff and NEI as
           they go into the home stretch.
                       We have specifically asked that the
           presentations have data to back up the opinions and
           conclusions, and at this point, I will hand it over to
           Louise Lund to start off with the staff.
                       DR. SHACK:  Before Louise starts, I would
           like to state that I do have a conflict of interest in
           this area, because Argonne is doing work on some
           generator programs for the NRC.
                       MS. LUND:  Okay.  Can everybody hear me? 
           Okay.  Good morning.  As Dr. Ford indicated, I am
           Louise Lund, and I am the section chief of the
           Component Integrity and Chemical Engineering Section.
                       And what I had hoped to present this
           morning is an overview of NEI 97-06, Steam Generator
           Program Guidelines, and give you kind of a basis for
           which you can understand the next few presentations,
           which one is going to be given by EPRI.
                       And then Jim Riley of NEI is going to make
           some comments, and then Emmett Murphy of the NRR staff
           is going to also get into more detail in some of the
           issues that are in my slides.
                       Okay.  This slide presents a little
           history of the staff's activities in the past years in
           the steam generator regulatory framework.  I think
           that most of you are familiar with that, and I am not
           going to spend much time on this, because I think that
           the committee is aware that there has been a
           rulemaking generic letter on different things that we
           worked through.
                       But I wanted to make a quick few points
           germane to today's discussion.  NEI informed the NRC
           in December of 1997 of the industry's intent to commit
           to a formal industry initiative called NEI 97-06, with
           all PWRs implementing at no later than the first
           refueling outage, starting after January 1st, 1999.
                       What this means is that the industry is
           currently implementing NEI 97-06 with the current tech
           specs.  In the next few slides, I will discuss the
           components of the industry initiative of the NEI 97-06
           document, the generic license change package, and the
           EPRI guidelines, and how these all fit together.
                       And to then discuss which parts the
           industry is currently implementing and what we are
           trying to move to.  The other thing is that another
           reason that I put this together is to kind of give you
           a sense for the dates on this, too.
                       Okay.  As promised, here is what the
           current framework looks like, and right now as you can
           see the current plant tech specs, and the NEI 97-06
           steam generator program guidelines that I just
           mentioned, what it is, is that it is high level
           guidance for utility steam generator programs.
                       And there is lower tier EPRI guidelines
           which give you more of a detailed day-to-day guidance,
           and it is referenced in the NEI 97-06 program
           document.  So the question is what are we moving to. 
                       Okay.  This is where we are going, having
           the NEI 97-06 program document the EPRI guidelines,
           and a generic license change package, which is the new
           part of it.  
                       And what it does is that it formalizes the
           NEI 97-06 into the NRC regulatory framework via new
           tech specs.  And how it is envisioned is a generic
           license change package will provide a framework for
           taking advantage of the flexibility envisioned by NEI
                       As proposed the tech specs and the generic
           license change package provide a framework for a fully
           performance-based approach.  Currently, NEI 97-06 and
           the EPRI guidelines are implemented in conjunction
           with the existing tech specs which are prescriptive,
           with the expectation that soon they will be
           implemented with the new tech specs in the new generic
           change package.
                       The advantage to the generic license
           change package to industry is a streamline process for
           gaining NRC approval of longer steam generator
           inspections strategies, alternate tube repair
           criteria, and new tube repair methods.
                       For example, licensees will be able to
           implement performance based strategies for determining
           inspection intervals which have been reviewed and
           approved generically by the staff, without the need
           for submitting changes to the tech specs.
                       The NRC also benefits, in that it is
           assured that the steam generator programs will be
           focused on tube integrity, rather than simply
           following prescriptive surveillance strategies.  
                       And just to kind of give you a sense for
           what is in the 97-06 document, the program
           incorporates a balance of these items -- prevention,
           inspection, evaluation, repair, maintenance, and
           leakage monitoring.
                       And I will discuss also a little bit about
           what the generic license change package incorporates,
           but it is also important to realize that --
                       DR. POWERS:  Can I ask a question?
                       MS. LUND:  Sure.
                       DR. POWERS:  You say a balance. 
           Presumably any mix of those things is a balance.  Is
           there some significance to the word balance?
                       MS. LUND:  Well, I think -- well, you
           know, I am not exactly -- I don't think there is
           really a terrific amount of significance to the
                       DR. POWERS:  That's what I thought.
                       MS. LUND:  But I think that there is --
           that as you look at it, none of these exist
           independent of one another, you know, I guess is
           probably a better way to put it.  
                       All of these, as far as your evaluation,
           your inspection, and what you repair, all of these
           don't exist independent of one another.  So you really
           need to consider all of them within the same context. 
           Does that make sense?  Do you understand where I am
           going?  Maybe the wording threw you off.
                       DR. POWERS:  It seems like the most
           hopeless -- I mean, there is nothing that I am going
           to take home with this.  I mean, I am not going to
           remember this particular slide for any significant
           period of time.  Maybe I wasn't intended to.
                       DR. FORD:  Well, maybe a better word might
           be interrelationship between these various parts? 
           They are synergistic to a certain extent.
                       DR. POWERS:  I guess I would understand it
           better if I thought I was working with steam generator
           tubes that are roughly intact, and don't have lots of
           cracks in them.  Is this directed towards Alloy 800
           tubes, or is this directed towards some better type or
           different type of tubes?
                       MS. LUND:  It is intended for all of the
           different types.
                       DR. POWERS:  Every one of them?
                       MS. LUND:  Every one of them, and I think
           that you need to have a program that makes sure that
           not only you consider the inspection and repair, and
           leakage monitoring.  
                       It is really a whole package, regardless
           of what type of tube material that you are talking
           about.  It is to make sure that you have a strategy
           for dealing with the as-found condition.
                       DR. POWERS:  So if I had a strategy on
           repair on detect, I would be okay, right?
                       MS. LUND:  As far as repair on detection
           for --
                       DR. POWERS:  Tubes?  Let's say I find a
           flaw.  Fix it.
                       MS. LUND:  Well, that has been one
           strategy for doing it in the past.
                       DR. POWERS:  Well, I think the difficulty
           with -- I mean, the repair on detection strategy, I
           would find that completely unacceptable, because it is
           what happens between the time that I fixed everything
           and the next time I look that becomes important.  
                       MS. LUND:  Yes, which I think is a key to
           this and why we are going away from just looking at
           surveillance intervals, and going to more of an
           approach where we do look at the condition, and we do
           look at what has been determined and evaluated as far
           as what the operational assessment -- you know, what
           the condition of the tubes are and what we predict the
           condition of the tubes to be at the end of the cycle.
                       And so I think that is certainly part of
           the new approach, and I think that Emmett is going to
           discuss this in more detail when he gets up here.  But
           that certainly is an important part of it.
                       DR. POWERS:  Okay.
                       MS. LUND:  Okay.  And I think that this
           one is another thing, and which we will discuss in
           more detail later, is that if it does establish
           performance criteria that define the basis for steam
           generator operability.
                       And which the performance criteria include
           the structural performance criteria, accident leakage
           and operational leakage criteria.  Now, the generic
           license change package, the utilities are to submit
           revised tech specs based on NRC approved generic
           license change package.
                       And the generic license change package
           will contain a commitment to follow NEI 97-06, and the
           licensee's submittal, as you will identify these three
           items -- the performance criteria and repair methods,
           and inspection interval criteria.
                       And we will be talking in some detail
           later about the inspection interval.  How we will do
           this is through revised tech spec and bases, and a new
           spec with new technical specification steam generator
           tube integrity, and a new administrative tech spec,
           which is the steam generator program.
                       This will include revised limiting
           conditions for operations specification, and for
           operational leakage, and a new limiting condition for
           operational steam generator tube integrity.
                       The new admin tech spec states that the
           steam generator program must be implemented to ensure
           that tube integrity performance criteria are
                       The licensees will be explicitly required
           to assess the conditions of the tubes, versus the
           performance criteria, and that shall be performed at
           each steam generator inspection outage.
                       Changes to performance criteria, tube
           repair criteria, and repair methods, are subject to
           NRC review and approval.  Now, just to give you a
           little bit of overview as to where we are.
                       This is the review status, is that the
           industry had requested inspection intervals beyond the
           current requirements, and where this is going to come
           in is actually in Rev. 6 of the APRI steam generator
           examination guidelines.  
                       Mohamad Behravesh from EPRI is going to
           discuss that in some detail.  In the initial part of
           the staff review, both the industry and the NRC were
           intending a review of performance based inspection
           intervals, and as we became aware of changes to the
           guidelines, it was apparent that the predictive
           methodologies to support performance based inspection
           intervals had not been fully developed.  
                       However, the industry is proposing a
           reference inspection interval strategy for the newer
           steam generator tube materials, and what I am talking
           about is 600 thermally treated and Alloy 690 than
           those currently allowed in the tech specs.
                       The industry is currently addressing both
           NRC comments and internal industry comments with
           respect to this proposal.  And the staff believes that
           this approach must ensure that tube integrity
           performance criteria will continue to be met and that
           tubing conditions not meeting the performance criteria
           will be promptly detected.  
                       So based on that the staff concluded that
           regulatory controls on the inspection intervals were
           needed, and what we proposed was incorporating
           provisions in the administrative tech spec regarding
           the use of NRC approved inspection intervals.
                       And we have reached agreement with
           industry on this approach.  So where we are now is
           that now that we have reached agreement with industry,
           we had a meeting to work out a schedule to reach a
           conclusion of the review of the generic license change
                       So one of the items that we have been
           asked to discuss is the schedule and based on recent
           meetings, we expect the industry submittal in mid-
                       After the submittal is made, we will use
           the process of issuing the safety evaluation that we
           previously informed the Commission that we would
           follow, and that was in SECY-00-0078, and sending it
           out for public comment, resolving comments, briefing
           the Commission, publishing it in a regulatory issue
                       And we anticipate that this will take
           approximately six months after we get the industry
                       VICE CHAIRMAN BONACA:  Ms. Lund, during
           the Subcommittee Meeting that we had last week, we
           really had some difficulty with the issue of going to
           a performance based, because the ability to determine
           tube integrity was not convincing at this stage.
                       And I think that the NRC is not convinced
           either yet.  And so we had some concern about this
           package coming, and then we had a presentation from
           EPRI that said that this is going to be far in the
                       Right now we are going from a prescriptive
           inspection interval process to a better and more
           conservative prescriptive process, or something of
           that kind.
                       MS. LUND:  Kind of a reference interval is
           what I think Emmett is calling it.
                       VICE CHAIRMAN BONACA:  Yes, it was
           specific to certain types of steam generators and so
           on.  And now when I look at your presentation, I get
           the message that actually this new package within 2002
           will also contain new criteria, new performance based
                       MS. LUND:  Well, it is going to include
           performance criteria, but the performance criteria,
           some of it is just more explicitly called out than
           what was called before.
                       But what I would suggest is that Emmett is
           going to actually discuss some of the components of
           it, and more of the details of what the performance
           criteria are.  So that would probably -- and not
           wanting to steal his thunder, maybe -- well, would
           that be acceptable?
                       VICE CHAIRMAN BONACA:  Sure.
                       MS. LUND:  Okay.
                       DR. FORD:  One of the conclusions from the
           meeting last week, Louise, was that if you take away
           the conclusion that I came away with, which was that,
           yes, in the long term -- and exactly what Mario was
           saying, that in the long term, yes, you are heading
           for performance based criteria.
                       But if we don't have the data quality to
           get that by the end or the middle of this year, and
           that we are going to a prescriptive --
                       MS. LUND:  To an interim stage.
                       DR. FORD:  That has not changed?
                       MS. LUND:  Right.  What we are doing is
           that as far as inspection intervals, we are going to
           have an interim step.  Do you want to address that,
           Emmett?  It looks like --
                       DR. FORD:  Well, so far, you have only
           been talking about -- in the words you have been using
           or saying performance based.
                       MS. LUND:  That's right, and the
           performance based is more on the way that the program
           is constructed, and the intent at the beginning was to
           make it performance based, including the inspection
                       But the actual issue that we have been
           wrestling with has been that we are not ready for the
           inspection interval part of it to be performance
                       DR. FORD:  So is it fair to say that the
           overall plan that you are proposing is going to be
           adaptable enough so that it can take a performance
           based, but right now practically it is sticking with
           a prescriptive --
                       MS. LUND:  Right, for that issue, because
           the program itself based on the condition monitoring
           the operational assessment, and looking at the
           conditions of your tubes, and looking at how they are
           going to perform for the next cycle, and doing all
           that evaluation, that is a performance-based part of
           the program right now.
                       And the part that we are still trying to
           iron out is this inspection interval strategy.  So
           does that make sense?
                       DR. FORD:  Yes.  
                       MS. LUND:  So I have just one more slide
           and then I am going to hand it over for you to get a
           lot more details on this.  In our long term action for
           review status is to resolve outstanding issues with
           the EPRI guideline documents, and this will have
           future benefits, such as permitting the use of
           intended performance based approach for inspection
           intervals, in lieu of these reference prescriptive
                       If there is no questions on this overview
           part of it, I would like to go ahead and turn it over
           for more specifics in the next couple of speakers.
                       MR. BEHRAVESH:  Good morning.  I am
           Mohamad Behravesh from EPRI, and before I go further,
           I would like to get an idea of how much time do I have
           for this presentation?
                       DR. FORD:  The whole time that we have is
           until 10 o'clock, and Emmett, it depends on how long
           you need.
                       MR. MURPHY:  I prepared a presentation
           that is very short, and so your questions will drive
           the length of it.
                       DR. FORD:  So you are the only two
                       MR. BEHRAVESH:  Well, Jim Riley from NEI
           will have some concluding remarks.
                       DR. FORD:  How long do you need?
                       MR. BEHRAVESH:  I think it would be a
           luxury to have about 25 minutes to 30 minutes.  If I
           could have that much, that would be good.  If I take
           less of that, then we will have time for questions.
                       DR. FORD:  Okay.  So, 25 minutes with
           questions would be perfect.
                       MR. BEHRAVESH:  As Louise mentioned, this
           entire framework of NEI 97-06 stands on these various
           pillars called guidelines, and the strength of this
           framework really depends on the strength of these
                       And one of these guidelines is the
           inspection guideline.  A lot of the issues related to
           steam generators, at the end it sort of culminates in
           inspection questions.  
                       So I would like to spend some time telling
           you about this industry document that details
           inspection requirements, and where it came from, and
           what it all involves.
                       The steam generator inspection guidelines
           goes way back to 20 years or so, and the reason for
           it, the impetus for it, was that there really wasn't
           any recommendations or any guidance on how to do steam
           generator inspections.
                       And unlike pressure vessels, and unlike
           piping, steam ASME was somewhat silent, and to this
           date it is still somewhat silent as it relates to
           steam generating inspections.  
                       So utilities took the initiative back in
           '80, putting a set of requirements together, and over
           the years that has continued, and from time to time
           they have revised it, and formalized it, and brought
           input from vendors to the process.
                       And they added some very important topics
           to it, namely performance demonstration, and it went
           on to a prescriptive sampling, and somewhat even
           changed the language 2 or 3 years ago that it is
           really no longer a recommendation or guidelines, but
           rather that it is requirements.
                       Everything has attached to it the word
           "shall" and it is sort of a de facto requirement for
           the utilities.  So the point that I want to make with
           this slide with you is that the set of guidelines that
           the industry used for conducting steam generator
           inspections is very mature.  
                       It is time tested, and it is field tested,
           and it has gone through a whole series of reviews, to
           the point that it brings us to Revision 5, and that
           has been what utilities have been using for the last
           3 or 4 years.
                       And in the guideline it also says that
           every two years it is required that we assess the need
           for revision of these guidelines.  That is that
           Revision 5 of the guidelines, based on utilities input
           and other input that we have received, have actually
           been pretty good. 
                       It has brought a lot of improvements to
           the practice.  However, it did lack one thing, and
           that is that as utilities went and replaced steam
           generators, and went to better materials, this
           revision, this addition of the guideline did not make
           any distinction between 600 mill annealed material and
           600 thermally treated, and 690, the newer material.
                       And so there was a lot of impetus for
           revising this, and for allowing for these new
                       DR. POWERS:  Is Revision 5 the 1997
           version, with all the strong language, the one that
           was enforced at Indian Point at the time that they had
           their tube rupture?
                       MR. BEHRAVESH:  It was one that they
           should have followed when they had the tube rupture.
                       DR. POWERS:  Oh, they should have? 
                       MR. BEHRAVESH:  Yes.
                       DR. POWERS:  Okay.
                       MR. BEHRAVESH:  This slide pretty much
           says what I mentioned to you, that the guideline
           delineates the hows and whats, and all those things as
           a result of using an assessment.  It is a utility
           developed document, and we have started work on
           Revision 6 in March of 200, and we expect to finish it
           by the middle of next year.
                       It has lots of things in it, but I am
           going to concentrate basically on a couple of issues. 
           The highlights of Revision 6 is these prescriptive
           examinations, and then some issues related to data
           quality which came out of the Indian Point 2, as a
           result of the experience at Indian Point 2.
                       We have a new addition of the new draft of
           this guideline out for draft out for review, and we
           should be receiving --
                       DR. FORD:  Mohamad, could you just expand
           a little bit on what you mean by data quality?  Is
           this laboratory data quality, field data, and what
           sort of scatters are we looking at?  What are the
           quality issues specifically?
                       MR. BEHRAVESH:  Sure.  
                       DR. FORD:  If you could go briefly over
                       MR. BEHRAVESH:  Yes.  Briefly, it is on-
           line monitoring of the data as you are collecting it
           to determine whether has the data quality, has the
           data deteriorated to the point that it can no longer
           be trusted for collecting and making decisions.  So
           changes have to be made.
                       And so it is on-line such that you would
           know that the data that you have used can be -- that
           the data that you have collected can be used, and if
           that is not the case, then remedies must be made.
                       DR. FORD:  So it is inspection data that
           you are talking about?
                       MR. BEHRAVESH:  Inspection data quality
           while you are collecting it.
                       DR. SHACK:  Sort of signal-to-noise?
                       MR. BEHRAVESH:  Signal-to-noise would
           certainly be the number one element, yes.  Data
           quality are other things, too.  For example, are you
           in the right tube.  I don't want to get mundane, but
                       DR. WALLIS:  Does it say what you do with
           the data once you have got it?
                       MR. BEHRAVESH:  Well, what you do with the
           data is that you do a whole lot of other things based
           on your analysis procedures.  But collecting it, and
           before you take the instrumentation out and leave the
           place, you want to make sure that what you have got is
           acceptable and useable.
                       DR. WALLIS:  But you are not addressing
           what you do with the data.
                       MR. BEHRAVESH:  Not at this stage, no. 
           There is a whole set of guidance on what to do with
           the data.
                       DR. FORD:  And on your graph beforehand,
           or you slide beforehand, you said when.  So there is
           a time component to this?
                       MR. BEHRAVESH:  Not to the data.  A time
           component to the data quality, but what I said by when
           had to do with prescriptive inspections; when do you
           do and how often.
                       DR. WALLIS:  It sounds like a ritual.  
                       DR. POWERS:  That is not a bad
                       VICE CHAIRMAN BONACA:  Yes, if that is a
           condition that is a ritual.
                       DR. POWERS:  You get to anoint a brief to
           it, and collect the data, and then they bless it.
                       VICE CHAIRMAN BONACA:  Yes.
                       DR. WALLIS:  Once a day and twice on
                       DR. POWERS:  And every day during a
                       VICE CHAIRMAN BONACA:  Then you hope and
                       DR. POWERS:  Twenty-four hours a day,
           three shifts.
                       VICE CHAIRMAN BONACA:  And then you hope
           and pray.
                       DR. POWERS:  And hope and pray that your
           probability of detection is high enough.
                       VICE CHAIRMAN BONACA:  Yes.
                       MR. BEHRAVESH:  Now, let's wait a minute
           now.  You have to consider the following.  It used to
           be that you would go there and collect a bunch of
           data, and go home, and then worry about what to do
           about it.
                       What is being done now is that know what
           it is that you are collecting, and is it what you
           intended to collect, and can you use it, and does it
           have all the attributes, before you leave the place. 
           It may sound like a ritual, but it is a good ritual.
                       DR. WALLIS:  Well, did someone go through
           the exercise of what you are going to do with the
           data, and how much data do you need in order to
           satisfy the needs of whatever the process is for
           processing the data?
                       MR. BEHRAVESH:  Yes.
                       DR. WALLIS:  And the questions which are
           being asked by the whole process?
                       MR. BEHRAVESH:  Yes.  There is a whole set
           of tables, and the rationale, and tables that says
           this is the data that you collect, and this is where
           you collect it from, and this is how many times you
           collect it, and how much you collect.
                       DR. WALLIS:  And you should deduce that
           from your needs for whatever it is or whatever the
           questions are that you are asking.  The process for
           collecting data seems to become lost once you have
           figured out what questions you are asking, and how
           much data you need, and on what frequency in order to
           answer the questions.
                       MR. BEHRAVESH:  That is correct.
                       DR. WALLIS:  Am I right in assuming there
           was a process of that type that you went through?
                       MR. BEHRAVESH:  Yes.  Now, in a nutshell,
           the big changes that are happening in Revision 6 of
           the guideline, in comparison to Revision 5, is that
           the distinction that has been made in inspection of
           600 mill annealed thermally treated, and 690 thermally
                       And those distinctions are that for 600
           mill annealed material that you inspect it at every
           outage.  For 600 thermally treated, it must be
           inspected at least every other outage.
                       And for 690 thermally treated, it must be
           inspected at least every third outage.  And this means
           that you cannot skip more than two times, and this
           means that you cannot skip more than one outage.
                       DR. FORD:  Last week, we discussed this,
           and there are two issues, practical issues.  
                       MR. BEHRAVESH:  Yes.
                       DR. FORD:  One is the probability of
           detection, and the other one is what is the database
           to give you those --
                       MR. BEHRAVESH:  I can get to that and
           these are all experience base.  This material has
           failed in service and is being looked at at every
                       In this material, there are, oh, 15 or 16
           plants in the U.S. that have this material, and they
           have gone without any cracking in them for as long as
           15 years.
                       DR. FORD:  And did I understand that there
           are some incidences of cracking of 600 TT?
                       MR. BEHRAVESH:  Well, two things.  There
           are alleged cracking in the U.S. that have not been
           confirmed.  For example, what they thought was
           cracking in the Braidwood and Bryon plants that are
           600 thermally treated, and they took three tubes out.
                       And after a destructive assay, they
           decided that those were really manufacturing flaws,
           and they were not cracks, and they were basically what
           is called OD groups.  This is in those two plants.
                       They thought that they had the same or
           they thought they had what appeared like cracking at
           Turkey Point 3 and 4, and then they went and did an
           additional examination with the ultrasonics, and in
           reviewing the data and comparing it with the other
           similar indications, they again have concluded that
           those are not cracks.
                       Now, there are facts that have been
           confirmed in this material in foreign plants, and
           there is an explanation for them.  For example, in
           France, they have quite a few of these, but their
           expansion are all very different, done differently,
           and what is called the KISS rule, which has introduced
           additional residual stresses.
                       And in those cases, the ones in France,
           they have failed in the cracking mode.  No such
           expansions do exist in the U.S.  There may be cases in
           Japan where again the thermal treatment has been
           different than in the U.S. based on everything that we
           know today.
                       Again, I need to add that this study is
           ongoing and we have a study under way to get all of
           these details in one place to support these things for
           the NRC review. 
                       That in everything that we know today,
           this material in the U.S. has not failed in the
           cracking mode, and the experience with it in the
           field, the number of plants are 13 effective full
           power years, and up to 15.
                       And there are two 30 plants, both of them
           are at 15 plus effective power years.  So this one is
           new and there have been no evidence of failure of it
           in the cracking mode in the field.  So there is data
           being collected for all of this.
                       DR. POWERS:  Your slide implies that the
           800 Alloy will be treated the same as the 600
           thermally treated?
                       MR. BEHRAVESH:  Pretty much.  That is what
           we are considering.
                       DR. POWERS:  Is there a reason for
           treating 800 the same as 600?
                       MR. BEHRAVESH:  Nothing that I can
           elaborate on. 
                       DR. POWERS:  I mean, the Germans seem to
           be pretty enthusiastic about 800.
                       MR. BEHRAVESH:  Yes, and 600 has not been
           bad here either.
                       DR. POWERS:  Yes, apparently not.
                       DR. SHACK:  Do we have any 800 plants in
           the U.
                       MR. BEHRAVESH:  Not fully, no.  Things are
           made with 800 material, but not fully steam generated
           plants.  Anyway, this is in a nutshell what the
           changes are.  Now, let's look and see --
                       DR. FORD:  Mohamad, you are going to get
           to this question about why these specific multiples in
           the inspection periodicities.  You are going to get to
                       MR. BEHRAVESH:  Well, I would come to it. 
           Again, I would come back to it and hopefully be able
           to answer your questions.  So when we go to 600 mill
           annealed, the requirement is that you inspect all of
           the tube in every steam generator within 60 effective
           full power.  And also it means that mechanical -- 
                       MR. ROSEN:  You are talking about full
           power months?
                       MR. BEHRAVESH:  Months, effective full
           power months, 60 effective full power months.  Steam
           generators shall be inspected at every outage, and
           every time you do an inspection, you must do at least
           20 percent random samples.  
                       If you do samples of less than 20 percent,
           this is really no change.  This is the way that we
           have been doing it in the Revision 5 as well.
                       DR. WALLIS:  Typically, how many months
           are there between outages?
                       MR. BEHRAVESH:  It depends on the outages,
           which are often times dictated by fuel cycles, and so
           you can assume about 12 months, all the way to 24
           months, but typically 18 to 22 months or so.
                       DR. WALLIS:  And this is 20 percent
           guessed at by some experts or where does it come from?
                       MR. BEHRAVESH:  Well, 20 percent is sort
           of the optimum sampling that if you do less, you are
           not going to get a lot more information.  And if you
           do more, it is not going to give you a whole lot more. 
           So it is backed by -- in fact, it was based on the
           study that was done -- 
                       DR. WALLIS:  So 20 percent if you do it,
           say, three times between the time that you inspect
           everything, and the chance of missing a cracked tube
           is pretty high.  Just take the probablistic thing. 
           You do three measurements of only 20 percent, there is
           probably a 50 percent chance --
                       MR. BEHRAVESH:  Well, the idea is that it
           doesn't matter how many cracks you have in tubes.  You
           need to catch one of them to have knowledge of the
           tubes being cracked.
                       DR. WALLIS:  But there is quite a chance
           that you wouldn't catch a particular cracked tube if
           you did that?
                       MR. BEHRAVESH:  A particular cracked tube,
           that is correct, but if you find a cracked tube, then
           you must expand your inspection all the way to a
           hundred percent, which would allow you to catch every
           cracked tube. 
                       DR. WALLIS:  I am just trying to get the
           rationale for it.
                       DR. POWERS:  Graham, do you think that is
           true that if I inspect 20 percent randomly selected,
           that I have a high probability of having missed a
                       DR. WALLIS:  Yes.
                       MR. RILEY:  This is Jim Riley from NEI. 
           Mohamad, would you take a couple of minutes and
           explain the degradation assessment?  That might help
           answer this question I think.  The selection of tubes
           is not completely random.  
                       MR. BEHRAVESH:  Well, as part of this
           whole process, you select the tubes to inspect, and
           also at the end you must inspect all of them.  You
           select them based on the knowledge of at which
           locations degradation may have the strongest chance of
                       DR. WALLIS:  Oh, so it is not random
                       MR. BEHRAVESH:  No.  Within a given
           population, once you have selected a population,
           within that population is random.  It is random.  
                       VICE CHAIRMAN BONACA:  But again going
           back to the previous slide, an important bullet is
           missing, which is that if you find one, you expand
           your inspection beyond the 20 percent?
                       MR. BEHRAVESH:  Oh, yes, exactly that.
                       VICE CHAIRMAN BONACA:  Okay.  That's
                       MR. BEHRAVESH:  In 600 thermally treated,
           if the steam generators are free from cracking, and
           that is a big if, you must inspect all of them first
           within 120 effective full power months, and --
                       DR. WALLIS:  If you know that they are
           free from cracking, you don't have to do anything.  
                       MR. BEHRAVESH:  Pardon me?
                       DR. WALLIS:  It seems to me that if you
           know that they are free from cracking, you don't have
           to inspect anything. 
                       MR. ROSEN:  Really, what is being said
           there is that if they have been free from cracking in
           the past.
                       DR. WALLIS:  If they were free from
                       MR. ROSEN:  Yes.
                       VICE CHAIRMAN BONACA:  If no cracks had 
           been identified yet.
                       MR. BEHRAVESH:  Once we get back here, if
           this material is cracking, you don't go through this. 
           You don't go through this.  The first time around is
           120 months, and 120 months is effectively about 10
                       And what I mentioned to you is that there
           are a number of plants that have 15 years of crack
           free experience.  So that is part of the rationale for
           this 120.  
                       Now, the second time around, the
           prescriptive methodology is getting more conservative,
           and you drop to 90, provided that you live through 220
           orderly and completely trouble free. 
                       If you live through that, then the next
           period would be 90, and after that, 60 and 60, and 60,
           and so forth.  
                       DR. FORD:  Mohamad, again looking at this
           graph, and the following graph, I come back to my
           original question.  What is the database upon which
           presumably a statistical analysis has been done to
           come up with these periodicities?  Where is that
                       MR. BEHRAVESH:  That database is the
           collection of 15 or 16 plants that have this material
           in them, and they have been operating for periods that
           exceed this number.  So, this number has been taken as
           a conservative representation of that experience.
                       If you have an experience that says 15
           years, I would say that at 10 years would be a
           conservative representation of that.
                       DR. FORD:  And maybe we are not playing
           fair, but have the staff seen that data, and have they
           confirmed that those are significant? 
                       MR. BEHRAVESH:  Those are public data, and
           those are all the -- 
                       DR. FORD:  Well, has the staff examined
           these data?  You can have publicly available data, but
           have they examined the data?
                       MR. BEHRAVESH:  There has not been a table
           that in one page that we have handed it to them, but
           they periodically get reports from all of the -- they
           continuously get reports from all of these plants that
           they know their operational experience.
                       And the other part of the answer to your
           question is that as I mentioned, we are embarking on
           a study that is ongoing now to formalize all of this
           information; that on one hand appears to be obvious,
           and on the other hand, doesn't appear to be obvious to
           the uninitiated.
                       DR. FORD:  I guess I am going away with
           the impression from this graph and the next one, and
           indeed the previous one, that these inspection
           periodicities are completely empirical.
                       MR. BEHRAVESH:  Empirical?
                       DR. FORD:  Yes.  Is that a fair statement?
                       MR. BEHRAVESH:  Yes, it is, experienced
           based.  So there is no closed form formula that I can
           put some input in it, and out comes on the other side
                       DR. WALLIS:  You could.  You could say
           that you want to be sure that there is some 99 percent
           probability that if there is a crack that you detect
           it before it becomes serious, and you determine from
           some technical basis how long you can allow it to be
                       DR. FORD:  Maybe we can cut this one
           short.  Emmett, are you going to discuss it?
                       MR. MURPHY:  I don't have viewgraphs that
           speak directly to your question.
                       DR. FORD:  But this is one of the concerns
           that you have, correct?
                       MR. MURPHY:  Yes.  
                       VICE CHAIRMAN BONACA:  Okay.  I'm sorry,
           but I would like to ask a question of clarification
           here.  Is the 120 90-60 starting from the
           implementation of the tech specs, or from the
           construction of the steam generator?
                       MR. BEHRAVESH:  From the replacement or
           construction of the steam generator, with a caveat
           that after the first cycle of operation -- because
           what happens is that once you start, at the end of the
           first cycle of operation, you do a hundred percent
           examination of everything to make sure that everything
           is okay.  And from that point onward, this clock
                       VICE CHAIRMAN BONACA:  Okay.  Very good. 
           Thank you.  
                       DR. FORD:  I keep coming back to where
           there is data out there, statistical data, and Staehle
           has done a lot of this sort of stuff.  Does this come
           into your argument?  I mean, that is scientific data.
                       MR. BEHRAVESH:  Those are all of the ones
           that we -- well, we thought that it was obvious, but
           apparently they are not.  We are collecting it to make
           this case as you are mentioning, and that is what I
           keep saying, is that it is ongoing now.
                       VICE CHAIRMAN BONACA:  But since you have
           no history of cracking whatsoever in the 650, and how
           could you possibly have a probablistic basis?  I mean,
           I don't understand that.  
                       DR. FORD:  Some of that is based on the
           laboratory data that --
                       VICE CHAIRMAN BONACA:  I'm sorry?
                       DR. FORD:  Some of it is based on the
           laboratory data.
                       VICE CHAIRMAN BONACA:  Okay.
                       MR. ROSEN:  Well, just because you have no
           failures doesn't mean that you can't do statistics. 
           You have thousands and thousands of tubes that have
           been in service for many years.  
                       VICE CHAIRMAN BONACA:  I am talking about
           the fact that you are changing from 1210 to 90 to 60,
           okay?  And you would have to have some criteria of
           understanding of how, for example, how cracks initiate
           and develop to the point where you can detect them.
                       I mean, it is not an easy task to simply
           understand -- well, all right.  Why don't we just hear
           from Mohamad further on this.
                       MR. RILEY:  This is Jim Riley again from
           NEI.  Let me talk a little about where we are going
           here.  This is a draft document and I would like to
           remind everybody of that.  The values that have been
           put into this document initially are based on
                       We have got a bunch of folks who are
           working on the documents that are experts in the
           field, and they have a good idea of what is going on
           out there, both within our country and outside.
                       And they have put together what they
           believe are achievable inspection intervals.  The
           industry is involved in a study to develop the basis
           for these intervals to back up what we are putting in
           this document.
                       Please, right now, these are what we have
           in a draft document.  We are developing the basis to
           prove that they are indeed the right intervals, and we
           will have that done before this document is issued in
           final form.  
                       There are lots of other things that I
           think Mohamad is going to go into that explains not
           only the basis, but why these values, even where they
           are, are quite conservative.  
                       We have what is called a degradation
           assessment, and we have briefly touched on it.  A
           degradation assessment is required before every steam
           generator inspection, and it is required every time
           you shut down your plant for a refueling outage, and
           you take a look at what is going on in my steam
           generators, and even if I am not doing an inspection.
                       And that degradation assessment looks at
           what is going on around the industry, and what is
           going on around the world.  Do I have anything, any
           mechanisms that are going on.  If I do, I need to
           evaluate how that affects me.
                       It may change the time that I have until
           I do my next steam generator inspection, and it may
           change what I look at when I do my inspections.  These
           degradation assessments plan.  
                       They plan what you are going to look at,
           and how you are going to look at it, and what
           techniques you are going to use.  And they, along as
           you are going through your conditions and looking back
           and determining what your steam generator looks at,
           affects your sampling.
                       How much do you sample, and what do you
           look at, and how do you look at it.  All of that then
           is rolled up into this operational assessment. The
           operational assessment looks at where am I now, and
           what is going on, and how long can I go before I have
           to worry about exceeding the performance criteria.
                       That establishes your next inspection
           interval.  All these values have to be supported by an
           operational assessment.  So there is a lot of things
           that are going on behind the scenes that back up these
                       DR. FORD:  And that's why those things are
                       MR. RILEY:  Yes.  
                       DR. FORD:  Sorry, Mohamad, that we got off
           on a different subject.
                       MR. BEHRAVESH: So if they are free from
           cracking, and you inspect a hundred percent of them in
           these periods -- and again these go way into the
           future, and these guidelines are supposed to get
           revised every two years, which means that if new
           information comes up any time within these, that these
           recommendations will change.
                       DR. WALLIS:  I don't understand how that
           -- how is that compatible with this bottom bullet
           about no SG can operate for more than two refueling
           cycles without being inspected.  There are lots of
           refueling cycles within 120.
                       VICE CHAIRMAN BONACA:  That is confusing,
           and I was speaking to that last week, because if it is
           a hundred percent of the tubes within 120 months, but
           every other cycle you have to inspect some.
                       DR. SHACK:  You inspect a 20 percent
                       VICE CHAIRMAN BONACA:  So, I guess --
                       DR. FORD:  I guess these are
           uncertainties, and I was trying to move it along here,
           guys.  My feeling is that all of these questions are
           tied up with the statistical evidence.
                       DR. WALLIS:  Sure.  Of course, they are.
                       DR. FORD:  They haven't shown us that it
           will be developed.
                       DR. WALLIS:  Well, I think these numbers
           ought to be deduced from something else.  Let these
           numbers be "X" and you solve from "X" by working out
           some other --
                       DR. POWERS:  Well, if it helps at all, if
           I assume that the probability in any given tube cracks
           is one in a thousand, and I take a sample of a fifth
           of the tubes, there is about a 50 percent chance that
           I am going to find any cracks.
                       If it goes up to five out of a thousand,
           there is only about a five percent chance that I am
           going --
                       DR. WALLIS:  There is one in a thousand
           that what you are looking for, or one in 10,000 for
           what you are looking for.  Are you looking for one
           tube or are you looking for 10 tubes typically before
           you do anything?  It is all tied to your action, and
           I want you to find and detect.
                       MR. SIEBER:  Right.  Three thousand.
                       MR. BEHRAVESH:  In a steam generator where
           you have two or three thousand, or something about
           that number of tubes, when you do 20 percent sampling,
           if you have 11 tubes in there that are cracked, this
           20 percent sampling allows you to catch at least one
           of them.
                       DR. WALLIS:  Yes, but is 11 tolerable is
           the question.  I mean, what is the threshold were you
           do something I think is the key question there.
                       MR. SIEBER:  Well, you something when you
           get the 40 percent through all, and detect that, and
           a single tube in a steam generator isn't going to
           corrode and crack all by itself.
                       The whole steam generator starts to go
           back the very day it is born, okay?  So when you take
           a 20 percent sample, you are going to take a sample of
           tubes that are beginning to corrode and crack and so
                       And that gives you the confidence to say
           I generally know what the condition of the steam
           generator is, even though you may not have found a
           defective tube, but you will find a corroded tube
           after a few years.
                       And once you find a defective tube, then
           all of a sudden --
                       MR. BEHRAVESH:  Well, if expansion comes
           into place, then you look at all of them, as opposed
           to --
                       MR. SIEBER:  And you look at them and
           everything that you can get to.
                       MR. BEHRAVESH:  Yes.  The objective is to
           detect the onset of degradation.  All you need to find
           is one degraded tube, and not even defective.  One
           tube that you believe to be degraded, that puts you in
           the expansion of your sampling.
                       Again, these periods must be supported by
           degradation assessment and operational assessment, an
           acronym for degradation assessment and operational
           assessment, which means that if your degradation
           assessment says that you are more likely to have
           degradation in your plant, then these things do not
           hold.  They must be revised.  
                       This is where the industry experience
           comes in.  You must also satisfy all of the secondary
           side requirements, meaning that foreign objects and
           things of that sort.
                       There is also a safeguard in there such
           that you don't inspect all of the tubes at the
           beginning of the period, and then go on for 10 years
           not looking at something, or inspect all of the tubes
           at the end of the period, going for 10 years and not
           inspecting everything.
                       And at least 50 percent of them must be
           done by about the mid-point within the period, and the
           other 50 percent towards the end.  And in all of
           these, no steam generator can go for more than two
           cycles without being looked at.
                       And then if cracking is discovered in any
           time along here, then these things will not hold, and
           you go to 600 mill annealed requirements, which means
           to look at every steam generator at every refueling
                       DR. WALLIS:  I could suggest that you skip
           this one, and it is exactly the same, but it is just
           different numbers.
                       MR. BEHRAVESH:  Different numbers.  Now,
           the basis for this is that you have 15/16 600
           thermally treated, and you have about the same number
           of 690 more oncoming on line, and if you look at the
           industry as one aggregate of so many steam generators,
           you will find out that with more steam generators with
           new materials, experience of every one of them must be
           considered in the collective experience.
                       And such that although a steam generator
           may not be looked at, although your steam generator
           may not be looked at at this time, someone else is
           looking at this, and someone else is looking at this,
           and all of that information must be considered.
                       And also if cracking is detected the
           inspection interval has to revert back to the 600 mill
           annealed, and the second requirement must be met, and
           of course this is a considerable enhancement over what
           is currently the law of the land, which is the
           technical specification, which says that you must do
           three percent in about every 40 months.
                       And it doesn't even say that that has to
           be a different three percent.  Effectively, you could
           go and look at the same three percent sample of tube
           within 40 months.  So it is a big improvement.
                       VICE CHAIRMAN BONACA:  When you are
           looking at this collective experience, I imagine you
           are also tracking differences in chemistry, and so on
           and so forth?
                       MR. BEHRAVESH:  Yes.  That is all part of
           the degradation assessment.
                       DR. WALLIS:  Now, the basis for being more
           conservative than the current tech spec is presumably
           experience, and statistics, or something?  Is there
           some reason why you have made it more conservative?
                       MR. BEHRAVESH:  Well, if you look at this,
           these are plans that have 600 mill annealed material
           that have all degraded, and 3 percent would have been
           hardly sufficient to detect the onset of that.
                       DR. WALLIS:  So then you can do so kind of
           math which says three percent leads ot something
                       DR. POWERS:  You need another term that we
           just don't have I think, Graham, to answer the
           question; and that is that given that there is a crack
           in a tube that you don't know about, what is the
           probability that that tube will rupture during a cycle
           of operation.  And that is a number that I just don't
                       MR. BEHRAVESH:  That's right.
                       DR. WALLIS:  Yes, but apparently his
           experience has led him to change the inspection, and
           so there must be some kind of qualitative connection
           between what you expect and what you --
                       MR. BEHRAVESH:  Yes.  The operational
           experience.  Remember that I said these guidelines,
           and these recommendations have been evolving over a 20
           year period.
                       And so once you started seeing a cracking
           through this type of material, it was obvious that the
           three percent was not the right number.  And I doubt
           that it has been exercised by anyone.
                       On the matter of data quality, is that the
           question is the data getting noisy to the point of
           effecting detectability and sizing, and this is really
           a synopsis of all the objectives for data quality.
                       And then these examination techniques
           specification sheets are all those attributes of a
           technique and system and those parameters that you
           need to follow.  
                       And then if data gets to get noisy and
           affects these parameters, and affects your probability
           of detection, and so the question again is to have the
           bounds of these examination technique specification
           sheets, and if performance has been exceeded such that
           the performance indices have been degraded, these are
           the basic questions that are being asked.
                       And as a result, the guidance provides
           frequency, location, acceptance criteria, and
           corrective action for each of the listed quality
           parameters.  And these are some of the attributes of
           Revision 6 of the guideline.
                       Currently as I mentioned, too, the draft
           of the guideline is outside for review, and we expect
           to get comments by December 18th, and start evaluating
           those comments early in January, with the hope of
           getting this revision out by the middle of the year.
                       VICE CHAIRMAN BONACA:  That is the same
           question that we had during the subcommittee meeting,
           and again you presented to us a plan that is going
           from a description inspection intervals to
           prescriptive inspection intervals.  
                       MR. BEHRAVESH:  Okay.  Let me take a
           minute to answer that.
                       VICE CHAIRMAN BONACA:  You didn't say
           anything about changing to --
                       MR. BEHRAVESH:  Sure.  I was looking at
           the time.  Let me take a minute to address that. 
           Everyone talks about prescriptive versus performance
           based, and most of them are saying that ultimately we
           have to go by way of performance based, where the
           prescriptive methodology is not good.
                       What you need to do in order to do
           performance based is that you need two things to do
           performance based.  You need data and you need
           methodology.  You can sit around the table and discuss
           methodology as long as you want until you agree upon
           methodology and put it aside.
                       When it comes to data, you can't
           manufacture data.  You can manufacture history, and
           you have the data that you have.  Now, if you take
           that data and put it through the methodology, then are
           you willing to accept the outcome.
                       If the outcome is very good, chances are
           that the outcome will be more credible.  If the data
           is questionable, then the outcome would not be very
                       The industry recognizes that the NRC
           recognizes that the way to go about this performance
           based, but right now if you don't have sufficient data
           as we have had an example, you put the data that you
           have in the methodology, and it comes out and says
           here you can go for about 22 years and not look at
           this thing.
                       And everybody says, whoa, wait a minute. 
           Do I really want to go 22 years without looking at
           this, and then you step back, and then the question is
           asked, well, what is the problem.  Why don't you
           accept this.  
                       Is it the methodology that you don't
           accept, or is it the data that you don't accept. 
           Well, data is what you got.  There are 690 and there
           are two plants in the U.S. that have the experience of
           about 8 years or so.
                       Is that sufficient information, and you
           can debate that.  Is that good enough information, and
           you can go along with it and accept it, and so as
           experience, as this collective experience is
           accumulated for all these plants, the industry as a
           whole will be in a much better position to use that
           data and put it in an acceptable methodology to come
           up with performance based.
                       And we have provisions for performance
           based within Revision 5 of the guideline, as well as
           within Revision 6 of the guideline.  In Revision 5, no
           one had taken it up.  
                       In Revision 6, some people have sort of
           experimented with it, and they are sort of discussing
           it, and discussing whether they want to go along with
           it or not.
                       And we anticipate that there will be more
           exercises in that arena and with the new agreements
           that are being discussed with NRC, there will probably
           be some limitations on the maximum interval that the
           utility can go without getting that approved by the
                       And I think Jim Riley had some concluding
           remarks as part of our collective representation.  
                       MR. ROSEN:  Well, I had something to say
           on a different issue.  
                       DR. FORD:  I will allow 10 minutes at the
           end here to ask the Committee here their advice as we
           move forward on this.  So between the two of you can
           you take 10 minutes?
                       MR. RILEY:  I think it is going to take me
           longer to walk up there than it is to tell you what I
           have to tell you here.
                       DR. FORD:  All right.
                       MR. RILEY:  I am kind of jumping subjects
           on you here a little bit.  My name is Jim Riley, and
           I am NEI's project manager for steam generator issues.
                       And I came here to talk about another item
           that we are addressing as an industry, specifically on
           an application of safety factors in one of our
           performance criteria.
                       Now, this is issue has not come up today,
           but I will go ahead lay it on you anyway.  We are you
           know have been working on this generic license change
           package for a number of years, and as it is getting
           nearer to its completion, we have asked the NSSS
           vendors to take a look at what we are putting down
           here to make sure that we are consistent with the
           design basis requirements.
                       Let me step back a little and put this
           into context.  As you have already been told, NEI 97-
           06 is the overall document that governs steam
           generator programs.  Its details are handled through
           a whole series of EPRI guidelines.
                       NEI 97-06 establishes what are called
           performance criteria to make sure that your steam
           generators continue to operate properly.  There is
           three of them.  
                       There is a structural integrity
           performance criteria which is what its name implies,
           and which ensures that the tubes are capable of
           withstanding the forces that they are going to need to
           withstand in order to prevent their failure.
                       There is an accident-induced leakage
           performance criteria that addresses how much they can
           leak, which again is based on design basis
           requirements and exposures, and those kinds of things.
                       And then there is an operational leakage
           performance criteria, which is one that you can
           actually measure real time while you are operating,
           and it is basically just a leakage requirement, a
           primary-secondary leakage requirement.
                       The three of them together act to ensure
           or to maximize the probability that you will maintain
           tube integrity between steam generator inspections. 
           And that is the whole goal of what we are doing here.
                       You know, the old tech specs were very
           prescriptive, and very small sample sizes, and they
           were based on surveillances that you did every time
           you shut down the new steam generator for inspection.
                       This whole program is set up much more on
           maintaining tube integrity.  It includes not only a
           look back at what my condition is right now, but it
           includes methodologies to look forward, and to make
           sure that the next time that you shut down and do an
           inspection, there is a very high probability that you
           will continue to meet your performance criteria.
                       So within all of this mixture, performance
           criteria are very important.  They are central.  As we
           were reviewing the performance criteria this summer,
           we found an issue that needs to be addressed, and
           right now it is an open issue, and I am not going to
           be able to give you much detail at all on the
           specifics because we are still looking at it.
                       But this is a performance criteria for
           structural integrity.  I won't read the whole thing. 
           The underlying portion of this is the portion that we
           have some questions about, and it has to do with what
           safety factor you apply to the loads during an
           accident condition.
                       The current performance criteria says that
           you apply a safety factor of 1.4.  It turns out that
           when we asked the NSSS guys to take a look at it,
           there was some questions about how that 1.4 is being
           applied under the different designs, and whether that
           criteria is accurate for everybody.
                       Now, all I can tell you at this point is
           that we are undertaking some work internal to the
           industry to take a look at how this 1.4 is applied,
           and may possibly end up revising the performance
           criteria to make sure that what it states can be met,
           will be met, for all the NSSS designs for the
           different steam generator designs that are out there.
                       We will incorporate that change, that
           generic license change package revision as we proceed
           for its final submittal to the staff at the middle of
           this year.
                       And we will involve the staff in our
           discussions on what we come up with on this
           application for safety factors and as we come up with
           something more concrete.  But this is another open
           issue.  That's really all that I have to say in the
           interest of moving things forward.
                       DR. FORD:  Thank you.
                       MR. RILEY:  If you have any questions on
           NEI 97-06, or how this all fits together --
                       DR. WALLIS:  Well, it seems to me that the
           testing has got to be related to the performance
                       MR. RILEY:  It certainly is.
                       DR. WALLIS:  And somewhere or another
           there must be a link that is explicit.
                       MR. RILEY:  The testing that we do is
           called condition monitoring, and it is done every time
           you do an inspection, and the testing includes all the
           stuff that Mohamad was talking about, or that his
           guidelines talk about.
                       DR. WALLIS:  He didn't explain how it is
           related to the performance criteria.
                       MR. RILEY:  No, there is a different
           guideline that is called the integrity assessment
                       DR. WALLIS:  But they must be linked.  You
           don't want to assure the others.
                       MR. RILEY:  Yes.  And the results of the
           testing gets fed into an integrity assessment that
           actually does an analysis of whether or not you meet
           the performance criteria now, and whether you will in
           the future.
                       DR. WALLIS:  Good.  Thank you.
                       MR. RILEY:  You're welcome.  
                       MR. MURPHY:  Okay.  I am Emmett Murphy of
           the Materials and Chemical Engineering Branch, NRR,
           and I have a relatively short presentation, but I am
           going to go out of sequence right from the get go.  
                       I want to first talk about performance
           sine what I say here I think will serve as useful
           background purposes for subsequent discussion about
           inspection interval issues.  
                       During the briefing that we provided to
           the subcommittee last week, questions were raised with
           respect to the basis and the adequacy of performance
           criteria that are being proposed for inclusion as part
           of the generic license change package.
                       Before answering that question directly,
           I would like to just reiterate that it was the intent
           -- it was ours and the industry's intent when
           developing these performance criteria to maintain
           consistency with the original design basis, in terms
           of structural margins and in terms of accident induced
                       This is also consistent with the
           philosophy of Section XI of the Code, which in the
           absence of a specific safety margin criteria, directs
           you back to Section III of the Code.  
                       Also, these criteria are consistent with
           the current licensing basis of PWRs as embodied in the
           specification plugging limits.  But are these -- well,
           before getting on to your question then, with respect
           to the issue that Jim Riley was just discussing
           concerning the 1.4., I can't really respond to what he
           said yet until we see what they come up with.
                       All I can tell you right now is that it
           has been our intent to maintain consistency with
           design basis and with the licensing basis, and to the
           extent that we have not fully done that, then of
           course we will be open to discussing how we do that,
           and I will just leave it there.
                       With respect to the thrust of your
           question from last week, I think we have to turn to
           experience, and what does experience tell us about the
           adequacy of these criteria.  
                       We have had eight tube ruptures.  When you
           examine the circumstances of these eight tube
           ruptures, the safety margin goal that you are trying
           to maintain really was not material to the
           circumstances of the rupture.
                       Five of these ruptures took place because
           the utility was not aware of the damage mechanism
           taking place in its generators.  Irrespective of
           structural margins that you are applying to your
           analyses, if you are not aware of the mechanism, it is
           going to hit you.
                       On three of the ruptures, the licensee
           utility had some knowledge of the damage mechanism,
           but he was not adequately managing the program, either
           because of inadequate inspections, or inadequate
           assessment of how quickly the damage mechanism was
                       Again, a question or an issue of safety
           margins was not really material to the circumstances
           of the rupture.  I think we also need to consider risk
           when answering the questions that arose last week.
                       The staff has examined risk issues
           pertaining to tube integrity in NUREG-0844, the steam
           generator U.S. side program.  Also more recently, in
           NUREG-1570.  In spite of the eight tube rupture events
           to date, the risk associated with spontaneous SG-TR
           events has been found to be acceptably low.  
                       Similarly, the risk associated with tube
           ruptures which occur as a consequence of transients or
           accidents that are within the design basis again have
           been found to be acceptably low.
                       Before going on, and as background for our
           next discussion on inspection intervals, I think it is
           important to note that this risk experience reflects
           the way that steam generators have been managed
           through the years.
                       And one of the important attributes of
           that management process has been to inspect steam
           generators in general in every refueling outage.  Very
           few plants have ever had the opportunity to operate
           for more than a single fuel cycle between inspections.
                       When plants were first coming on line in
           the late '60s and early '70s, they ran into problems
           very quickly, and they didn't have the opportunity to
           take advantage of the 40 month provision in the tech
                       It has only been in very recent times, and
           I don't know how many plants with the latest
           replacement generators were able to take advantage of
           the 40 months.  I think it is only a handful; 1, 2, or
           3, something along that order.
                       And in the main through the years people
           have been examining their steam generators every fuel
           cycle, and these risk numbers reflect that practice. 
           And as we contemplate moving to longer intervals, we
           have to consider what are the risk implications.  
                       Are we able through inspection and
           analysis and tube integrity assessment to ensure that
           the necessary margins will be maintained.  And a final
           point about risk, is that the studies that have been
           performed do show that medium performance criteria are
           also important from the standpoint of minimizing
           severe accident risk beyond design basis type
                       However, severe accident risks as you,
           know, clearly there is a lot that we don't know about
           it as of yet, and it is a subject that is being
           assessed as part of the SG action plan.
                       That program addresses issues addressed or
           identified by ACRS in its DPO findings, and it is our
           objective that an approved generic license change
           package will not increase risk relative to the current
           regulatory framework.  
                       We will go now to inspection intervals,
           and let me make a couple of observations here up
           front.  I think as we sat in the back of the room
           listening to some of the proceedings it was observed
           that perhaps there is some confusion or some confusion
           between the performance-based attributes of the
           framework, the new framework that we are trying to put
           into place in the tech specs, versus a prescriptive
           versus performance based strategy for dealing with
           inspection intervals.
                       We are putting into place a framework
           which is performed based in the sense that the
           specific objective of the program is to ensure that
           you are meeting the performance criteria; rather than
           to ensure that you are inspecting every so often, and
           you are plugging tubes essentially at 40 percent.
                       But the specific objective is to or the
           main objective is to ensure that you are meeting the
           performance criteria, and that you periodically assess
           the condition of the generators relative to that
           performance criteria.
                       And in that sense we are performance
           based.  The tech specs do not include the development
           of strategies for determining inspection intervals
           that are also performance based.  That is, you have
           determined how long you can operate before you will
           exceed the performance criteria.
                       As we discussed last week, and as we have
           been talking about today, so far the guidelines are
           not sufficiently well developed to allow people to
           make these kinds of determinations accurately.  
                       And so we rely on a prescriptive strategy,
           which based on experience expects to prove corrosion
           resistance of the material, and give us reasonable
           assurance that we will be maintaining the performance
                       Time is very limited, but we have had the
           opportunity to look at the strategy, the prescriptive
           strategy that Mohamad was presenting earlier, and we
           commented on that strategy quite extensively back in
                       We identified quite a number of issues,
           and among them was the importance of receiving as much
           information as can be gathered concerning operating
           experience with the Alloy 600 thermally treated and
           Alloy 690 thermally treated tubing.
                       We were aware of reported incidences of
           cracking abroad, and we didn't know the circumstances,
           or even if it was real, or if people were just making
           conservative calls.  So, we do think that this is an
           important consideration as we consider revising the
           prescriptive strategy for determining inspection
                       The second important issue has to do with
           the definition of active degradation.  Mohamad talked
           about operating for 2 or 3 cycles, depending upon your
           tube material, to the extent that you are free of
           active degradation.
                       Well, that is not quite exactly what they
           mean.  Active degradation doesn't mean the absence of
           degradation activity under the proposal.  It does
           allow for a certain minimal or a certain level of
                       And we think that there needs to be a
           tightening up of that definition to ensure that we
           don't have significant degradation actively taking
           place, particularly cracking activity, if one is going
           to be operating for multiple intervals.
                       DR. FORD:  Just to -- Emmett, because of
           time, do I in just reading the rest of that, you
           really are reiterating the concerns that we have
           independently brought up.  Is there anything new with
           the "burst" small volumetric flaws?  What is that in
           relation to, the last bullet? 
                       MR. MURPHY:  This is an issue that is not
           uniquely related to inspection intervals.  It is a
           general issue that exists with respect to how you
           conduct condition -- as to how you conduct operational
           assessment relative to the performance criteria for
           small volume flaws.
                       It is an issue that has existed all along
           up to now, and going to a new regulatory framework
           doesn't change the significance of this issue, unless
           you are going to operate from alternate intervals.
                       To the extent that the treatment of small
           volume flaws relative to performance criteria is to
           the extent that that treatment is not appropriate,
           then if you go to longer intervals, then you can
           aggravate the potential risk associated with that.
                       So we would need -- that to the extent
           that we are going to go along with longer intervals,
           we need some interim approach for ensuring adequate
           safety margins for small volumetric flaws. 
                       DR. WALLIS:  I hate to slow you up --
                       MR. MURPHY:  Well, let me make one more
                       DR. WALLIS:  This is the first time in
           time detectable cracking that I have seen any evidence
           that this inspection procedure somehow is related to
           what you think of the actual characteristics of the
                       How does it behave is probably related to
           what you do, and this is the first time that I have
           seen any kind of mechanical term defined which you are
           actually trying to detect.  
                       And so it would be useful if there were
           some scientific basis for how you expect things to
           perform, and what you do in order to measure various
           characteristics of performance.
                       MR. MURPHY:  Well, we have a fleet of
           plants out there with advanced materials, and there
           will be plants on the leading edge in terms of the
           accumulated operating time.  
                       DR. WALLIS:  Well, I am not saying that.
           I mean, it is not a random process.  Either they fail
           randomly or there is some kind of physics which says
           that they tend to last pretty well up to certain
           times, and then they begin to crack.
                       And then they are all going to crack very
           soon after that.  That there is some kind of
           mechanical basis for how you expect them to perform,
           and which has terms associated with it.
                       And that has got to be related to what you
           actually have as a strategy to inspect, and this is
           the first time that I have seen a term actually
           brought up in the discussion.  
                       MR. MURPHY:  Okay.  Well, let me just make
           one other general point.  It is not the objective.  It
           has never been the staff's objective either with the
           old regulatory framework or with this new one to
           eliminate the likelihood of future tube ruptures.
                       The strategies that we have been
           considering are not going to accomplish that
           objective.  It is to maintain the frequency of such
           occurrences, tube ruptures or situations where we
           don't meet the performance criteria's sufficiency low
           frequency, and that the risk implications are
                       DR. KRESS:  Do you have a number for that
           sufficiently low frequency that you want to give us?
                       DR. POWERS:  If I back calculate from the
           numbers, and assuming that the past frequency is
           acceptable, which I think Emmett said, it turns out
           that they want to be 99 percent sure that tubes are
           not cracking.  And it comes out in such a round number
           that I can't believe it is an accident. 
                       DR. WALLIS:  Well, that must be based on
           some model of how they crack.
                       DR. POWERS:  It is strictly a probablistic
                       DR. WALLIS:  Yes, assuming that it is
                       DR. POWERS:  Yes.
                       DR. WALLIS:  But it ain't random.
                       DR. POWERS:  Well, I don't know whether it
           is or not, but what struck me as interesting is the --
                       DR. WALLIS:  Well, old tubes are more
           likely to crack than new ones presumably.  So, it is
           not random.
                       DR. FORD:  I'm just forgetting the time. 
           Mr. Chairman, what leeway do I have on time?  I mean,
           we can call a halt right now.
                       VICE CHAIRMAN BONACA:  Well, I was just
           pointing out that we had a goal to even shorten the
           upcoming 50.44, and so your time is very short.  I
           would say another five minutes, and then that's it.
                       DR. FORD:  So, five minutes? 
                       VICE CHAIRMAN BONACA:  Yes.
                       MR. MURPHY:  All right.  I would like to
           complete a thought.  It is not our objective to
           prevent tube ruptures entirely.  In some small
           frequency of tube ruptures and failure to meet the
           performance criteria is not going to be unacceptable.
                       With that in mind, I would argue that it
           is possible to entertain the notion of longer
           inspection intervals before you developed
           methodologies and data, and have data concerning how
           long it is going to take to develop degradation
           mechanisms that you have not seen before; new cracking
           mechanisms and I-690, for example.  
                       How long is it going to take to initiate
           those cracks before it may threaten the performance
           criteria.  So long as the industry works in a
           coordinated fashion, and everybody is aware of
           everybody else's experience, and to the extent that
           one plant is finding cracking, then that information
           is disseminated among all the utilities.
                       And then all the utilities take that
           experience into account in determining when they
           should be doing their inspections.  This kind of
           empirical or approach based on experience I think if
           properly set up and properly designed will do or will
           accomplish the objective of minimizing the frequency
           at which you're not meeting the performance criteria
           and minimizing risk at acceptable levels.
           That concludes my comments.
                       DR. FORD:  Bear in mind that the objective
           of this particular presentation was to let the full
           committee know where we stood on that particular steam
           generator program, and to give advice on any of the
           outstanding technical issues that still remain as they
           go into the home stretch.
                       Obviously, we don't have time for us to go
           around the table, and I would suggest that we do that
           when we come to the letter writing session.  Thank
                       MS. LUND:  Excuse me, but could I make one
           quick comment?  On the handout, I noticed that there
           was a typographical error, and I just wanted to bring
           that to everybody's attention on the last page.
                       Emmett, I assume that it is fuel cycles
           not to exceed 24 effective full power months, correct?
                       MR. MURPHY:  That's correct.
                       MS. LUND:  Okay.  It says EFPY, but it is
           actually supposed to be EFPM, and so as long as this
           is transcribed, at least we have it in the record,
                       VICE CHAIRMAN BONACA:  Thank you.  Any
           other questions or comments from the members?  If not,
           we will recess now for 15 minutes.
                       (Whereupon, at 10:01 a.m., the meeting was
           recessed, and was resumed at 10:18 a.m.)
                       CHAIRMAN APOSTOLAKIS:  The next topic is
           Proposed Rulemaking for Risk Informed Revision to 10
           CFR 50.44.  Dr. Shack is the Chairman of the
                       DR. SHACK:  Okay.  We previously reviewed
           a staff feasibility study of developing a risk
           informed version of 50.44, and we now have a draft
           version of the rule, and it is presumably the first
           fruits of the Option 3 approach, and Mr. Markley will
           be giving us an introduction to the proposed rule.
                       MR. MARKLEY:  Good morning.  My name is
           Tony Markley, and I work in the Office of Nuclear
           Reactor Regulation.  I think you know one of my
           siblings here at the table.  
                       Before we get too much further, I would
           like to introduce to you our project team.  We formed
           this team back in early March.  To my left is Mike
           Snodderly, who is in the Division of Systems and
           Safety Analysis.
                       We have in the audience Jim Pulsipher, who
           worked with us on the standard review plan and other
           input; David Cullison, who worked with the regulatory
           guidance; Pete Precinas and Charlie Tinkler from the
           Office of Research; Kerri Kavanagh, who worked with us
           on tech specs; and a number of other folks who
           provided us input on new reactors and so forth.
                       Basically, we are here today to discuss
           the draft proposed rulemaking for Risk Informed 50.44,
           and we would appreciate receiving your feedback on our
           plans as we present them to you on moving forward with
           that rule making.
                       With respect to the background, as Dr.
           Shack indicated, this issue has been before the
           Committee in the past in the form of SECY-00-0198,
           where a framework for risk informing Part 50
           regulations was presented.
                       In addition, in that paper the
           presentation also included some specific
           recommendations on how we were going to proceed with
           risk informing 50.44, and we also included within that
           paper an attachment that addressed some of the issues
           that the petitioner, MR. Bob Christie, had raised with
           respect to 50.44.
                       Since that time, we have received a staff
           requirements memorandum from the Commission in
           January, that directed the staff to proceed
           expeditiously with the rulemaking on Risk Informed
                       We sent another paper to the Commission in
           August, and that was SECY-01-0162, that specifically
           indicated the staff's plans for moving ahead with
                       There were some changes in approach that
           were identified in that paper.  The first was that as
           opposed to providing a voluntary alternative rule
           making for 50.44, the staff looked at the fundamental
           mission of what RIP50, Option 3, was all about.  
                       That was going back and looking at the
           fundamental reason why we had a regulation, and what
           does it do, and how does it work.  And then once we
           had established a need for that regulation, we took
           risk insights and risk information to look at the
           relative importance of what we think we need for
           regulation in that area.
                       And then to the extent possible
           afterwards, we tried to incorporate some performance
           based concepts in he regulation, and specify more of
           what is to be done, as opposed to how to do it.
                       So this was discussed in the SECY that
           went up in August, and there was another item that
           went up and that was a major issue in that paper.  One
           of the issues that was identified in this RIP50 option
           pre-process associated with 50.44 was an issue
           associated with the MARK III blowing water reactor
           containments, and the PWR ice condensers.
                       The issue basically involves if you look
           at the risk significance sequences for those
           facilities that would get you into a severe accident,
           if it involves station blackout, then was there a need
           for independent or backup power to the igniter systems
           of those facilities.
                       This was identified as a generic safety
           issue and has been transmitted to the Office of
           Research, and the Office of Research is now in the
           process of evaluating that issue.  
                       And that is moving on an independent track
           to the rulemaking.  So we are not constrained in terms
           of moving ahead by the resolution of that generic
           safety issue.
                       With respect to stakeholder interactions,
           we have had numerous public meetings on what --
                       CHAIRMAN APOSTOLAKIS:  Are you going to
           use your transparencies or --
                       MR. MARKLEY:  I'm sorry.  I am going right
           ahead here.  We will get this up.  I had a captive
           audience here that was paying attention to my speaking
           and no watching the board here.
                       Now, we did have quite a number of
           stakeholder interactions on this subject.  We held
           meetings and workshops in 1999 and 2000, and based on
           the input and feedback that we received back from
           that, that has been taken into consideration, in terms
           of where we stand on this proposed rule.
                       We also had a Commission briefing
           associated with the Option 3 and some of the other
           risk informed initiatives in July.  In addition to
           that level of stakeholder interaction, the Commission
           also asked the staff to make draft rule language
           available to stakeholders.
                       And as of November 14th, we did have draft
           rule language for 50.44, as well as some bracketed
           information, to try and provide stakeholders some
           additional insights into where we were headed with
           that regulation, rather than just raw old language on
           the paper for them to try and guess at the meaning.
                       So we received a few comments and
           questions and so forth on that, that we have had by
           means of telephone communications and so forth, but we
           have yet to have any formal comments submitted.
                       Well, I take that back.  We did receive
           Mr. Christie's comments yesterday, which I believe you
           received as well.  So with that, let's go to the next
                       Basically where I want to take you with
           what we are doing with this rulemaking today is
           basically a summary of the changes -- where we are,
           and where we are going, and what we believe the rule
           is going to look like.
                       For currently licensed and future reactor
           licensees, this rulemaking will eliminate the design
           basis accident as a source of significant combustible
                       Based on the analysis and the work that
           was done in the framework, and previous studies, and
           so forth, the design basis LOCA accident just cannot
           produce enough combustible gas to challenge
                       The second thing that this rule will
           accomplish is that it eliminates.  Because the design
           basis accident in essence goes away, you are more
           concerned with beyond design basis, and consider
                       And you no longer have a need for
           recombiners, or purge and repressurization systems. 
           So this rule eliminates the requirements for those. 
           Once again because the design basis accident is
           eliminated, your monitoring systems and other
           combustible gas control systems no longer meet the
           definition of equipment required to be safety related.
                       So what this will in essence do will allow
           the commercial grade procurement of these items.  The
           next item.  While these are -- well, while the items
           that I have discussed already allows a significant
           level of burden reduction for current licensees and
           future licensees, there are a number of regulations
           within 50.44 that are still pertinent.  And this
           rulemaking endorses those regulations.
                       DR. SHACK:  One thing I noticed is that
           most of this is consistent with what you had in the
           feasibility study.  The one element that I found that
           was different was that you were retaining the 75
           percent hydrogen generation; whereas, the feasibility
           study talked about coming up with a combustible gas
           source term that was more mechanistically based.
                       And you seemed to have punted on that.  Is
           that a matter of time, or you just decided that it
           wasn't worth the effort?
                       MR. SNODDERLY:  Dr. Shack, let me try to
           address that.  Basically what we found was that the
           time frame that had been established for completing
           the hydrogen source term was such that it was going to
           hold up the rule.  
                       And the Commission challenged us to
           present alternatives for speeding up the rule.  One of
           the options that we presented was to use the 75
           percent metal/water reaction, and that has been
           produced to the Commission, and we have not heard from
           them one way or the other on how we should proceed.
                       But we were told to continue to proceed,
           and we have done so.  But we feel that the -- and we
           discussed the adequacy of the 75 percent metal/water
           reaction in Section 4 of the paper.  
                       And basically what we found was that the
           hydrogen source term work that was performed by the
           Office of Research -- Charlie Tinkler and Pete
           Precinas are here today from the Office of Research to
           help support us.  
                       But what we found was that the hydrogen
           generation -- that there is two key variables when
           designing a hydrogen control system.  One is the
           amount of hydrogen, and the other is the generation
                       And what we found was that the generation
           rates that were used in the design of the existing
           systems are comparable to the generation rates that
           are being calculated in the latest calculations.
                       So that gives us a level of comfort to go
           ahead and continue with the 75 percent metal/water
           reaction as an adequate basis for the purposes of this
                       MR. MARKLEY:  One thing that I would like
           to comment on is that the thought and the idea as far
           as evaluating the individual source terms, and going
           through uncertainty analysis, that effort is still
           under way, and is progressing as we speak.
                       Its function will be more to help resolve
           that generic safety issue associated with the MARK
           IIIs and PWRI condensers.  We will get some additional
           information as far as other containment types, but the
           initial indications that we have coming back from that
           is that even with this source term here, we are still
           on the mark for where we need to be with this
                       DR. SHACK:  Why embedded in the rule,
           rather than -- you know, than putting it in some
           guidance document?  
                       MR. MARKLEY:  Essentially, this is a
           historical construct.  One of the things that we are
           looking at is that we are risk informing, and we are
           trying to make the rule more aligned to the needs that
           are out there.  
                       The decision was made to utilize this, as
           opposed to trying or as opposed to waiting for perhaps
           more detailed information.  
                       DR. SHACK:  Well, I can see utilizing it. 
           But once you put it in a rule though, then it is a
           rule change, and you are going to have a Reg guide
           associated with this rule anyway.  Why not --
                       MR. MARKLEY:  Does it potentially beg
           another rulemaking down the road if we get better
           information and so forth?  Yes, it possibly does. 
           That is a risk that you do take by putting this in
                       Okay.  The last bullet on this page also
           deals with a petition that we received.  We became
           aware of this petition a little bit later in the
           process.  Another part of our organization was working
           on it, and looking at it.  
                       We had already made a decision to focus
           the applicability of this rule on the containment
           types, and the challenge to those containments, as
           opposed to using specific fuel cladding information.
                       And whether it is a Zircalloy or ZIRLO, or
           that sort of thing.  So we had already encompassed
           that when we became aware of this.  So that is another
           change to this rule.  And the next slide.  
                       DR. SHACK:  And couldn't -- well, couldn't
           that potentially affect the source term though?
                       MR. MARKLEY:  We are not so much -- I
           think in this case if we are looking at the studies,
           the source term that is out there for the large drawn
           and sub-atmospherics will not challenge the
                       The source term that is utilized in the
           MARK I's and MARK II's will not challenge those
           containments because those are maintained inerting,
           and we are maintaining the requirements for those.  
                       The question is whether the PWR ice
           condensers and the MARK IIIs.  We don't have a final
           answer yet on whether this source term would be
           significantly increased for those facilities, or it
           could be less for those facilities.
                       We are relying on this research to be
           accomplished, and that research is supporting the
           generic safety issue.  And that generic safety issue
           as I indicated earlier is on its own independent track
           for resolution.  
                       And what comes out of that could affect
           rulemaking in terms of the PWR ice condensers and BWR
           MARK IIIs, or it could affect plant specific backfits
           if you will.
                       You are looking at a very defined set of
           population with the BWR MARK III containment types. 
           I think there is four in the country, and then the ice
           condensers, I think there is eight facilities for
                       So it is a discreet population that you
           are dealing with.  So our decision at this point is to
           let the generic safety issue sort itself out, and what
           comes out of that, then we will look at the
           implications of that, and whether we need to go to
           plant specific backfits, or do we need to get back
           into the rulemaking space to adjust what we have here
           for the ice condensers and MARK IIIs.
                       On our next slide, the first bullet for
           future reactors is we took advantage of this
           opportunity at risk-informing 50.44 to try and
           consolidate a lot of the combustible gas regulations.
                       Part 52 has a reference in there that
           endorses the technical requirements of 50-34(f), and
           we essentially pulled those at the same level that
           they currently exist into the revised 50.44, with two
                       The exceptions of course being as noted on
           the previous page that you don't need recombiners, and
           that you are allowed a commercial grade other
           combustible gas controlled systems and monitoring
                       There were some other conforming changes
           that we had to consider when making this change.  We
           looked at that, and we made a change to -- this says
           50.43, and that should be 50.34, and that is a typo on
           my part, but 50.34(a)(4).
                       And we are revising that to make sure that
           the need for high-point vents for the reactor coolant
           system is addressed in the applicant's PSAR.  We are
           also revising adding a new paragraph (g) in 50.34 that
           will ensure all new applicants include the analysis
           required by 54 in their applications.
                       And the issue with the high-point vents. 
           This was an interesting issue that we discussed in the
           team.  It basically came down that the high- point
           vents were more associated with proper ECCS
           functioning than it really dealt with combustible gas.
                       Now, it did provide a combustible gas
           source term to the containment, which the containment
           systems have to deal with, but we felt that this
           regulation was really misplaced in 50.44, and so we
           are going to move that to 50.46, in a new a paragraph
           in 50.46.
                       Now, in moving this, I will say that there
           is an independent effort that is trying to risk-inform
           50.46.  So we chose not to try and improve the
           language or the risk basis for these high-point vents.
                       Rather, we let the team that was working
           on that project have that opportunity.  The last item
           on this page is the change to 52.47.  That is that
           reference to the technically pertinent requirements of
           50.34(f), the post-TMI stuff.
                       What we essentially did was say that
           except for X, X, and X, that would have referred them
           to the requirements if it was combustible gas control
                       And essentially that is it with respect to
           where we are trying to go with 50.44.  Now, we do have
           two other slides here that I wanted to present to you,
           because we do have two petitions for rulemaking and
           you have been apprised certainly of one, if not both
           of them.
                       The first one, of course, is Mr. Christie,
           who has made presentations here in the past.  The
           proposed rule and his petition are significantly
           consistent in terms of where he felt the regulation
           ought to go, and in terms of what we came up with, and
           where we believe the regulation ought to go.
                       There is only three areas that we differ
           a bit, and one is the functional requirement for
           hydrogen monitoring.  He didn't think that there was
           a need for monitoring.  Well, from a combustible gas
           basis, we would tend to agree with him.
                       However, the monitoring of combustible gas
           in the containment is pertinent in your response to
           the emergencies, both for the actions that the
           operators would have to take, as well as input into
           emergency planning decision makers on whether your
           containment barrier is being challenged, and do you
           need to initiate protective action recommendations to
           either evacuate the surrounding population, or have
           them sheltered.
                       And so the monitors still provide a
           significant function, but it just is not combustible
           gas control.  And since we are looking at a regulatory
           efficiency issue, would it be better to just keep all
           this monitoring here in one place, or try and put it
           in emergency preparedness and so forth, and we look
           from an efficiency standpoint to maintain it in the
           existing 50.44.
                       The other area that we differed from Mr.
           Christie's petition is the capability for ensuring the
           mixed atmosphere.  We still feel that is very
           important, and that they have either passive or active
           means to have a mixed atmosphere, and to preclude
                       We will probably still have the potential
           for the flaming or the burning of the hydrogen, but we
           would certainly like to preclude the detonation aspect
           of it.  
                       DR. SHACK:  You had indicated that you
           would accept either passive or active means?
                       MR. MARKLEY:  That is the way that it
           currently exists.
                       DR. POWERS:  Right.  When they propose the
           passive means; that is, natural circulation will
           accomplish the mixing, what standards of proof do you
           require on that?
                       MR. SNODDERLY:  Dr. Powers, I will try and
           answer that.  I think what we were trying to do here
           was to codify the fact that active systems are
           important for ensuring a mixed atmosphere.  
                       But during station blackout those systems
           are not available, and as part of the IPE process,
           licensees were requested to go through their
           containments and look for possible vulnerabilities.
                       So the answer to your question is what we
           would like to do is to formalize and put into the
           regulatory guide that guidance which is consistent
           with that which was used to implement that part of
           Generic Letter 88-20.  
                       We want licensees to be aware of places
           where possible stratification could occur, and to be
           aware of that.  And for future designers, we want them
           to keep in mind the importance of having an open
           containment and want good communication between
           compartments to assist in natural circulation.
                       DR. POWERS:  In a station blackout, you
           have steam enerting also on your site, and so it is
           not so important to have a well-mixed atmosphere
           there; is that true?
                       MR. SNODDERLY:  Yes.  But again I think
           the purpose of the rule is to communicate the fact
           that mixing is an important aspect of reducing the
           risk from combustible gas, and you can accomplish that
           by active systems, such as fan coolers and sprays.
                       But in the absence of those systems, we
           also need to look at the fact that you may be
           susceptible because of stratification.  Now, the fact
           that you have steam is also going to be on your side,
           per se, but as time goes on that steam will be
           condensing out.
                       And certainly if you engage containment
           sprays you are going to be taking the steam out of it
           to some extent, and you will have some separation of
           the hydrogen.  I think that is one of the insights
           that we have also gained from the Office of Research.
                       And that is that if you were in station
           blackout situation, and then if you did get power back
           and you decided to use the sprays, it is important --
           well, one aspect would be to bring one train on at a
           time, as opposed to two trains.
                       There was some experiments done at Sandia
           that looked at the fact that if you got sprays back
           and you quickly took out the steam, could you go into
           the detonable region.
                       And what they found was that for
           prototypical spray rates that it did not appear to be
           a vulnerability.
                       DR. POWERS:  I wouldn't think so.  I mean,
           mixing -- I mean, you turn on the sprays, and you
           condense the steam, but in doing that you do an awful
           lot of mixing.  
                       MR. SNODDERLY:  That's right.
                       DR. POWERS:  And so I guess what I am
           driving at really is that I am trying to see how this
           plays out looking at like an AP600 type design, where
           you have a feed up until a cooled dome, and you are
           relying on the flow in that dome region to keep from
           ending up with a stratified hydrogen layer at the top.
                       MR. SNODDERLY:  Yes.  We wrote the rule in
           a way that the licensee could meet it with that type
           of an approach, and we would expect the analyses that
           were done in support of AP600 to meet that
                       Now, for current plants though, we would
           not expect them to do anything more than what they
           have done --
                       DR. POWERS:  Well, you have really
           answered my question, which was were you thinking
           about AP1000.
                       MR. SNODDERLY:  Yes.
                       DR. POWERS:  And the answer is yes.
                       MR. SNODDERLY:  Yes.
                       DR. POWERS:  Okay.
                       MR. ROSEN:  Your presentation is silent on
           the impact of these activities on technical
           specifications.  Could you tell me what you think
           about that?
                       MR. MARKLEY:  I think actually that there
           is going to be a lot of benefit to technical
           specifications.  We included in the package some draft
           changes, and essentially all the text specs with
           respect to hydrogen monitors are being proposed for
           elimination because this is more in terms of the
           emergency response and that type of activity.
                       And we don't normally have emergency
           response equipment in tech specs.  With respect to the
           oxygen monitors for the inerted containments, we are
           proposing to maintain those in technical
           specifications, because how do you know if your
           containment is inerted unless you have a monitor that
           would provide that indication.
                       And so we would look for that to still be
           retained in tech specs.
                       MR. SNODDERLY:  And if I could add that we
           have Kerri Kavanagh here from the Standard Technical
           Specifications Branch, and she has been a member of
           the team and has helped us in this area.  
                       What is interesting is that if you look at
           5-36 and the four criteria for tech specs, the fourth
           criteria talks about demonstrating that the structure
           system or component is needed in tech specs because of
           risk significance.  
                       This is a criteria that is not used very
           much at all, but we used it in this case in trying to
           make the determination of what stays in tech specs and
           what doesn't.
                       As Tony mentioned, we have determined that
           an inerted environment for MARK I's and II's is risk
           significant.  That would stay in the tech specs, and
           the oxygen monitors for verifying that would also
                       But now the basis will change slightly,
           and instead of being there for design basis accidents,
           it will be there for Criteria 4, and the fact that it
           shouldn't be risk significant.
                       Now, if you look in the past, hydrogen
           monitoring was there for design basis accidents, and
           to know when to turn on the recombiners, or when you
           might have to use the vent and purge system.
                       Now what we have found is that -- and
           maybe also what was needed was to actuate hydrogen
           igniter systems in MARK IIIs and ice condensers. 
           Well, there is other indications that you can use to
           determine when you should turn those on.
                       And as Tony said, the hydrogen monitors
           now are more for core damage assessment and emergency
           planning, and to be consistent, they would not lead to
           -- hydrogen has not been shown -- hydrogen combustion
           has not been shown to be a risk significant threat to
           containments because of the mitigative features that
           have been put in.
                       So that made us say, okay, we don't need
           hydrogen monitors to actuate those mitigative
           features, but we do feel that we need them to support
           adequate severe accident management, and therefore, we
           felt that it was supported removing these from the
           technical specifications.
                       MR. ROSEN:  Well, your comments have been
           responsive with regard to monitoring, but what about
                       MR. SNODDERLY:  Control?  No changes. 
           Igniters will stay in the tech specs, and inerting
           from MARK I's and II's will stay in the tech specs
           because those systems have been shown to be risk
           significant in the absence of those systems.  So
           that's why they need to stay in the specifications.
                       MR. ROSEN:  What about -- well, control in
           large dry containments, PWR?
                       MR. SNODDERLY:  There aren't -- currently
           the only -- the recombiners are in the tech specs, and
           we proposed to remove those from the tech specs and
           large dry containments because they would not impact
           risk significant source terms.
                       The problem that you have is that the
           recombiners work at 200 standard cubic feet per
           minute, and when you talk about a large dry
           containment with a volume of 2 million cubic feet, it
           takes seven days to turn over that containment volume. 
           And so the recombiners were not shown to mitigate the
           consequences of --
                       MR. MARKLEY:  Basically, they are very
                       MR. ROSEN:  So for summary in a large dry
           containment, you would not be required to continue to
           operate the recombiners.
                       MR. MARKLEY:  That's correct.
                       MR. ROSEN:  And they could be moved from
           the plant effectively?
                       MR. MARKLEY:  That's correct.
                       MR. ROSEN:  And the control or the
           monitoring would be required to remain, but would not
           be safety grade anymore?
                       MR. MARKLEY:  That's correct.
                       MR. SNODDERLY:  Exactly.  It would just be
           a functional requirement and it would be removed from
           the tech specs and it could be met with commercial
                       MR. ROSEN:  Thank you.
                       MR. MARKLEY:  The last item on this page
           is that we did explain the basis for the exceptions
           that we took in the statement of considerations.  The
           last slide that I have is with respect to the NEI
                       And as we had stated previously, they were
           concerned about the restrictive applicability language
           of using Zircalloy and ZIRLO, claddingness, and the
           applicability entry for the existing 50-44. 
                       And as I indicated earlier, we early on
           decided that that was not an appropriate applicability
           statement for what we were trying to deal with in
           terms of the subject matter.
                       So as you have seen in our discussions
           today, the new rule as we propose it focuses on
           containment types for the applicability of the various
           technical requirements.
                       There is going to be many different types
           of fuel come up, and certainly the pebble bed reactor
           and other things of that nature, and there is other
           things that we probably can't perceive at this time.
                       So this concludes our presentation, and I
           would certainly be happy to entertain any additional
                       DR. SHACK:  Any additional questions from
           any of the Committee Members?  There being none, then
           thank you for a very clear and lucid presentation on
           the proposed rule.  
                       MR. MARKLEY:  Thank you.  
                       CHAIRMAN APOSTOLAKIS:  Okay.  So we will
           recess until 1:30.
                       (Whereupon, at 10:50 a.m., the meeting was

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