Thermal-Hydraulic Phenomena - June 12, 2001


                Official Transcript of Proceedings


Title:                    Advisory Committee on Reactor Safeguards
                               Thermal-Hydraulic Phenomena Subcommittee
                               Issues Associated with Core Power Uprates

Docket Number:  (not applicable)

Location:                 Rockville, Maryland

Date:                     Tuesday, June 12, 2001

Work Order No.: NRC-250                               Pages 1-244

                   NEAL R. GROSS AND CO., INC.
                 Court Reporters and Transcribers
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                          (202) 234-4433                         UNITED STATES OF AMERICA
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                               JUNE 12, 2001
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                            ROCKVILLE, MARYLAND
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                       The ACRS Thermal Phenomena Subcommittee
           met at the  Nuclear Regulatory Commission, Two White
           Flint North, Room T2B3, 11545 Rockville Pike, at 8:28
           a.m., Dr. Graham Wallis, Chairman, presiding.
                 DR. GRAHAM WALLIS, Chairman
                 DR. AUGUST CRONENBERG, ACRS Senior Fellow
                 DR. F. PETER FORD, Member
                 DR. THOMAS S. KRESS, Member
                 DR. GRAHAM M. LEITCH, Member
                 DR. VIRGIL SCHROCK, ACRS Consultant
                 DR. ROBERT E. UHRIG, Member           ACRS STAFF PRESENT:
                 PAUL A. BOEHNERT, ACRS Staff Engineer
                 JOHN HOPKINS, NRR
                 RALPH CARUSO, NRR
                 DONNIE HARRISON, NRR
                 JACK ROSENTHAL, RES
                 TONY ULSES, NRR
                          AGENDA ITEM                      PAGE
           I.    Introduction . . . . . . . . . . . . . . . . 4
           II.   NRC Staff Presentations:
                 John Hopkins, NRR. . . . . . . . . . . . . . 5
                 Ralph Caruso, NRR. . . . . . . . . . . . . . 9
                 Donnie Harrison, NRR . . . . . . . . . . . .66
                 J. Rosenthal, RCS. . . . . . . . . . . . . 140
           III.  ACRS Fellow Presentation
                 Dr. Cronenberg . . . . . . . . . . . . . . 161
           IV.   G.E. Nuclear Energy Presentation
                 Introduction . . . . . . . . . . . . . . . 211
                                                    (8:28 a.m.)
                       CHAIRMAN WALLIS:  The meeting will come to
           order.  This is the meeting of the ACRS Subcommittee
           on Thermal-Hydraulic Phenomena.  I am Graham Wallis,
           Chairman of the Subcommittee.
                       In attendance are ACRS Members Peter Ford,
           Graham Leitch, Robert Uhrig, and Thomas Kress; and the
           ACRS Consultant, Virgil Schrock.  We miss Novak Suber,
           who is usually at these meetings, and  we think maybe
           he is here in spirit, and at least we will try and
           make up for him.
                       The purpose of this meeting is for the
           Subcommittee to discuss potential issues for
           consideration by the NRC staff pertaining to its
           review of applications for core power uprates.
                       The Subcommittee will gather information,
           analyze relevant issues and facts, and formulate
           proposed positions and actions as appropriate for
           deliberation by the full Committee.
                       Paul A. Boehnert is the cognizant ACRS
           Staff Engineer for this meeting.  A portion of this
           meeting will be closed to the public to discuss
           General Electric Nuclear Energy proprietary
           information.  That will be this afternoon.
                       The rules for participation in today's
           meeting have been announced as part of a notice of
           this meeting previously published in the Federal
           Register on May 30, 2001.
                       A transcript of this meeting is being
           kept, and will be made available as stated in the
           Federal Register notice.  It is requested that
           speakers first identify themselves and speak with
           sufficient clarity and volume so that they can be
           readily heard.
                       We have received no written comments or
           requests for time to make oral statements from members
           of the public.  Now, we are going to discuss the power
           uprate program and I simply note that these are one of
           the events in this year and the near future which is
           likely to have a significant effect upon nuclear
           generation in this country.
                       Last week, we heard that the industry
           plans to go for something like 10,000 new megawatts of
           uprate power.  So we are really looking forward to
           hearing about this, and I will call upon Mr. John
           Hopkins, from the NRC's Office of Nuclear Reactor
           Regulation to get us started.
                       MR. HOPKINS:  Thank you, Mr. Chairman.  I
           am John Hopkins, Senior Project Manager in NRR. With
           me at the table are Mark Rubin, Donnie Harrison, and
           Ralph Caruso; and we have more staff members seated
                       I appreciate this opportunity to come and
           talk to the subcommittee about power uprates.  We are
           mainly going to focus on extended power uprates today. 
           Let me briefly again show the main agenda.
                       As you can see, Ralph Caruso, for Reactor
           Systems, will talk about our efforts so far in Duane
           Arnold inspection; and Don Harrison will then talk
           about PRA risk considerations.  Again, mainly focused
           on Duane Arnold, but additional.
           And Jack Rosenthal, from the Office of Research, will
           give a presentation.
                       We are prepared to answer other questions
           that may arise that specific presenters do not cover. 
           As you mentioned, Mr. Chairman, there are many power
           uprates that are going to be coming in.
                       The staff has reviewed several smaller
           uprates, but now the really extended power uprates are
           starting to come our way, and Duane Arnold is the
           first big one really, a 15 percent.
                       And as you can see by the review
           schedules, all of these reviews are fairly aggressive. 
           The staff anticipated in a review of our topical
           reports that it would probably take us  12 to 18
           months to do a power uprate review, and we are trying
           to beat that by a few months.
                       CHAIRMAN WALLIS:  And an aggressive review
           is one that goes quickly?
                       MR. HOPKINS:  Yes, that's right I meant.
                       CHAIRMAN WALLIS:  Well, it probably should
           be aggressive as well.
                       DR. HOPKINS:  Our staff is competent and
           I am sure they will be.
                       CHAIRMAN WALLIS:  Thank you.
                       MR. HOPKINS:  Clinton is the last one
           mentioned, and that is expected to come in next week
           and will be at 20 percent.  Additionally, there are
           other plants that have expressed interest in extended
           power uprates that we expect to come in at the end of
           the year, and that have not -- that I have not
           bothered to list.  Again, Duane Arnold --
                       DR. LEITCH:  These are all boilers, or all
           they constant pressure uprates?
                       MR. HOPKINS:  Yes, to my knowledge, these
           are all constant pressure uprates.
                       DR. BOEHNERT:  John how many more are you
           expecting?  Do you have any idea on that?
                       MR. HOPKINS:  I can't recall.  Maybe
           Mohammed Swaybe could comment on that.
                       MR. SWAYBE:  My name is Mohammed Swaybe.
           We are generating -- we have a survey underway right
           now, and we will be giving that information to ACRS
           hopefully this week.
                       DR. BOEHNERT:  Thank you.
                       CHAIRMAN WALLIS:  Are these all similar
           kinds of boilers, or are they different kinds of
                       MR. HOPKINS:  They are really different
           kinds of boilers.  Dresden, Quad Cities, and Duane
           Arnold are all fairly similar.  But Clinton is
           different from them.
                       DR. UHRIG:  That is a later generation?
                       MR. HOPKINS:  It is just the later
                       MR. UHRIG:  It is a Mark 3 containment.
                       CHAIRMAN WALLIS:  Okay.
                       MR. HOPKINS:  And Clinton is BWR-6 and the
           others are I believe BWR-3s, and that's all.  If there
           are no further questions for me, I would like to start
           with Ralph Caruso.
                       CHAIRMAN WALLIS:  What do all those T's
           mean up there?
                       MR. HOPKINS:  Target.
                       CHAIRMAN WALLIS:  Oh, target.
                       DR. SCHROCK:  The extended uprate program,
           have these same plants had smaller uprates previously,
           or these will be the first?
                       MR. HOPKINS:  Duane Arnold, I believe, has
           had a smaller uprate previously.  I don't believe that
           the others, Dresden and Quad, or Clinton, have had
           smaller uprates.
                       MR. CARUSO:  Good morning.  My name is
           Ralph Caruso, and I am the Chief of the BWR Nuclear
           Performance Section and Reactor Systems Branch in NRR. 
           I am talking to you this morning about the audits that
           were performed in March of this year regarding the
           Duane Arnold power uprate.  If I could have the
           background slide.
                       To describe the background here, the Duane
           Arnold power uprate was submitted in the fall of last
           year.  The staff has been performing a review since
                       The staff review is focused primarily on
           determining compliance with the topical report, known
           as ELTR2.  That is one of the two licensing topical
           reports that General Electric has submitted and that
           the staff has accepted for use in doing these power
           uprates on a generic mission basis.
                       DR. KRESS:  Your title says that this is
           an audit result.  I am not sure that I know what an
           audit is in this sense.
                       MR. CARUSO:  Well, this is an audit
           because it was done in conjunction with an ongoing
           licensing action, and I will explain a little bit more
           as I go along about what the individuals did.
                       And the idea is that we are trying to
           approve a licensing action, and as part of that
           approval, we can go to the vendor or to the licensee
           site and audit their calculations and their methods,
           and their results.
                       DR. KRESS:  Okay.
                       MR. CARUSO:  Rather than relying upon
           their submittals, we can actually look at the actual
                       DR. KRESS:  Okay.  Good.  Thank you.
                       MR. CARUSO:  And as I said, this was done
           in support of the power uprate, and I think at several
           earlier meetings I made a commitment that the staff
           would be doing these audits for all of these power
           uprates that involve large power increases on the
           order of 20 percent.
                       The audit was performed the week of March
           26th by a team of four staff members, and I see three
           of them here in the room today, and they are here if
           I get into trouble.
                       CHAIRMAN WALLIS:  Ralph, you were auditing
           what the vendors do.  Is the NRC making independent
                       MR. CARUSO:  It would depend on the issue.
           We have the ability to do that, but it all depends on
           what we find and what we determine is necessary to
           complete the review properly.
                       CHAIRMAN WALLIS:  But you have not done
           any yet then?
                       MR. CARUSO:  I can't think of any.  No, I
           don't believe we have done any for this.  That's
           interesting.  I have my staff shaking their head no,
           and I have a licensee shaking their head yes.
                       MR. ULSES:  The containment systems branch
           is performing an audit.
                       MR. CARUSO:  The containment systems
           branch.  I don't do the containment portion of it, and
           on the reactor system side, we are not doing it.  But
           I believe the containment people are.a
                       DR. CRONENBERG:  Ralph, is the
           documentation on the audit and what your staff finds,
           is it part of a particular license application by
           Duane Arnold, or will you be documenting it in a
           separate report a general audit of calculational
           procedures, or is this going to be tied to each
           particular plant?
                       MR. CARUSO:  The calculations that are
           audited for each licensee will be reported as part of
           the SER for that licensee, okay, because the audit is
           done to support that application.
                       We may find issues that have generic
           applicability, and we will deal with them
           appropriately, but they are properly dealt with for
           each licensee as they come up because they are done as
           part of that review.  The next slide, the audit scope.
                       This audit considered five issues.  The
           first was the SAFER/GESTR LOCA methodology, which is
           the licensed approved methodology for LOCA at Duane
           Arnold.  It looked at the implementation of what is
           called long term stability operation IV.
                       BWR stability is an issue that has been
           looked at for at least -- well, since BWR's were
           developed, but over the past 10 years, a number of
           options have been identified for plants to address the
           issue of stability, and the detection of stability,
           and the suppression of it.
                       And there are a large number of options,
           depending upon the manufacturer of the detection and
           suppression equipment that licensees install in their
                       Duane Arnold has chosen Option 1-D, which
           I believe is the GE Solomon on-line stability
           monitoring system; and what we did was that we looked
           at how that was implemented for Duane Arnold.
                       We also looked at the GELX14 correlation,
           which is used for GE12 and GE14 fuel, and heat
           transfer correlation as part of the design of the
                       We also looked at reactor cordizine
           issues, and the methodology and uncertainties used in
           the safety limit MCPR establishment, Minimum Critical
           Power Ratio.
                       CHAIRMAN WALLIS:  When you looked at these
           did it turn out that stability or fuel design were
           important issues for operates?
                       MR. CARUSO:  Well, I will give you the
           findings for each one of these, and then some of the
           issues that came out of them.  Actually, these
           significant issues.  Let's go to the next slide.
                       For the SAFER code, generally, we found
           that the analyses for the rated conditions complied
           with the SER, and the codes were appropriately
           applied.  We looked at the actual calculations, and we
           looked at the results, and we looked at the inputs.
                       DR. KRESS:  Are there for the Chapter 15
           type design basis accidents?
                       MR. CARUSO:  These are the SAFER/GESTR
           LOCA calculations, the licensing basis calculations
           for design basis access.
                       DR. KRESS:  Just for the LOCAs?
                       MR. CARUSO:  The LOCAs, SAFER/GESTR;
           that's what that is used for.  One of the findings was
           that there was a question about the use of
           uncertainties that are derived from some TRAC
           calculations and from full power operations.
                       These uncertainties were developed for
           normal operating conditions, but then they were
           applied to analyses of the single loop operation,
           which we don't think is necessarily appropriate.
                       However, when you look at how they applied
           them, and the conservative penalty factors that they
           apply to single loop operation, we don't think that
           this is a significant issue.  We will be discussing
           this with the licensee and with G.E., but this is not
           really a significant issue.
                       DR. KRESS:  How about the LOCA analysis? 
           They showed that they were still below the limit on
           peak clad temperature and oxidation amount?
                       MR. CARUSO:  Yes.
                       DR. KRESS:  But did they approach it very
           closely, or did they change --
                       MR. CARUSO:  You mean how close they came?
                       DR. KRESS:  Yes.
                       MR. ULSES:  This is Tony Ulses of the
           staff.  I can't recall the exact numbers, Dr. Kress,
           but I believe there certainly was an increase in the
           actual PCT, but I don't know that I would really
           attribute that to the actual power uprate itself, as
           much maybe to the fuel design change, if anything else
           I would say.
                       But they certainly had a lot of margin to
           do the PCTs is my recollection for the Duane Arnold
                       DR. KRESS:  Yes, the reason that I asked
           the question is that if they were already well below
           the PCT, and changed 15 or 20 degrees, I am not
           worried much about it.
                       But if they were pretty close to it, and
           got even closer, then I might worry about the
           reduction of margins beyond something that might be
                       DR. KRESS:  It sounds like it wasn't much
           of a change.
                       MR. ULSES:  Yes, sir, that is my
           recollection.  It wasn't much of a change, and I
           believe they still have quite a bit of margin as I
                       CHAIRMAN WALLIS:  Maybe we can get the
           answer from GE this afternoon.
                       MR. CARUSO:  This is realized. This was
           not or is not a simple straight power uprate.  I mean,
           they are changing fuel types as part of this change,
           and that will induce its own changes in analysis
           results for all sort of different accidents.
                       DR. KRESS:  Plus, we are changing flow,
           and are they doing anything to the turbine generator?
                       MR. CARUSO:  I believe they are making
           significant changes to the secondary side in order to
           be able to use the power that is coming out of the
                       DR. KRESS:  So, you know, you get a lot of
           things that could affect the whole thing?
                       MR. CARUSO:  That's correct.
                       DR. SCHROCK:  The original licensing of
           Duane Arnold was on the old evaluation model prior to
           the new rule in '89.
                       MR. CARUSO:  SAFER/GESTR is a -- no,
           actually, I believe it is an '83.472 method.  It is an
           anomaly in Appendix K evaluation model.
                       DR. SCHROCK:  That was my recollection,
           but what is the significance --
                       MR. CARUSO:  It is a little bit more
           complex than that.
                       DR. SCHROCK:  -- of your second bullet
           here; uncertainties derived from TRAC?  That conjures
           up the new rule in which you have to evaluate the
                       MR. CARUSO:  Tony, can you explain the
           details of that?
                       MR. ULSES:  The best way to describe the
           SAFER/GESTR model is that it is sort of a hybrid I
           would say, Dr. Schrock.  Really, what it is, and just
           like Ralph said, is that they are conforming with
           Appendix K, but that they are trying to demonstrate a
           little more realistically what the actual margins are
           in the LOCA calculation by trying to use the code more
                       And when we were working on the review and
           approval of the code, one of the ways that they
           attempted to try and demonstrate the accuracy of the
           method was to compare to some TRAC calculations, but
           that certainly was not the only thing that they did.
                       But they also did the calculations to the
           available experimental data, and what really came out
           of the TRAC SAFER/GESTR calculations was really
           basically the uncertainty term which they are adding
           on to the SAFER/GESTR methods as a penalty if you
                       So I guess I would say that the reliance
           on TRAC and the  SAFER/GESTR method is actually
           reasonably minimal.  But I certainly see where you are
           coming from.  This is not a best estimate LOCA
           methodology by any means.
                       DR. SCHROCK:  Well, that is what I am
           getting at, is what is it and where are we in terms of
           the -- well, I get a little confused on these
           acronyms, and SAFER/GESTR gets muddled up in my memory
           with GESTAR.  Was it that GESTAR came later?
                       MR. CARUSO:  It is all muddled up together
           with GESTAR.
                       DR. SCHROCK:  It is, yes.  And I remember
           that we had an extensive review of the GE methodology,
           which was approved in the '80s, late '80s sometime. 
           I don't remember the date exactly.
                       But it would be helpful to me to
           understand what it is that they are doing now, brand
           new core configuration, and how is this new license
           going to be qualified against an old Appendix K
           approach, and against a new approach, which is the one
           that was reviewed by the ACRS some 12 or 13 years ago. 
           What is it?
                       MR. CARUSO:  This is the approved
           methodology as it was reviewed and discussed with the
           ACRS back in the '80s, subject to modifications that
           have been made over the years to correct errors, and
           to make changes as is allowed under 50-46 and Appendix
                       So it is the approved model, and that
           model --
                       DR. SCHROCK:  The model that G.E.
           developed was in response as I remember it to a SCS
           paper which allowed the first step in applying the
           best estimate methodology in licensing.
                       And it was before the rule change, but it
           essentially attempted do something like the -- I am
           having trouble coming up  yet with another acronym.
                       In any case, a best estimate application,
           as opposed to the old Appendix K.  Now what I am
           hearing is that, no, this is an Appendix K approach.
                       MR. CARUSO:  No, I think Tony explained
           that I think the topical report that you are referring
           to, or the Commission paper that you were referring to
           was SCS 83.472.  That was the Commission paper that
           allowed this to be done, and SAFER/GESTR is an 83.472
                       DR. SCHROCK:  And wasn't Arnold licensed
           before that took place?  When was Arnold originally
                       MR. HOPKINS:  I'm sure it was in the 
                       MR. CARUSO:  That's correct, and it was
           licensed before those methods, but it has since
           started using the SAFER/GESTR methodology.
                       DR. SCHROCK:  So the new license will be
           on the new basis then?
                       MR. CARUSO:  Yes.
                       DR. SCHROCK:  Okay.  Thank you.
                       MR. ULSES:  Well, actually, they are
           currently licensed for SAFER/GESTR, Dr. Schrock.  They
           would have come in with a plan specific licensing 
           topical report, and I would say sometime in the '90s
           probably to actually make the change fro the old
           evaluation into the SAFER/GESTR method.
                       MR. CARUSO:  We don't know offhand when
           they made the change.  I don't know if there is anyone
           from Duane Arnold who knows that.  If someone there --
                       MR. BROWNING:  My name is Tony Browning,
           and I am from Duane Arnold.  Yes, we converted to the
           SAFER/GESTR LOCA methodology in 1986.
                       MR. CARUSO:  Okay.
                       DR. LEITCH:  The term rated conditions as
           used on this viewgraph, is that -- are you referring
           to the present license level or to the uprated
                       MR. CARUSO:  The uprated conditions.  When
           I say uprated, that means not the nominal full-power
           rated conditions.  With single-loop operation, you
           generally can generate full-power on a single-loop
                       DR. LEITCH:  These comments all refer to
           the uprated conditions?
                       MR. CARUSO:  Yes.  These were audits of

           the calculations that are used to support the power
                       CHAIRMAN WALLIS:  And what is a single
           loop operation with a BWR?
                       MR. CARUSO:  BWRs have two recirculation
           loops and it is possible --
                       CHAIRMAN WALLIS:  You mean the pumps?
                       MR. CARUSO:  One of the recirculation
           pumps will stop.
                       CHAIRMAN WALLIS:  Okay.  So it is not
           really a loop.  It is part of the one loop?
                       MR. CARUSO:  No, there are two loops, each
           has a --
                       CHAIRMAN WALLIS:  Oh, they are actually
                       MR. HOPKINS:  Yes.
                       MR. CARUSO:  Yes.
                       CHAIRMAN WALLIS:  Okay.  There is some
           baffles or something that separates the loops?
                       MR. CARUSO:  No, they have --
                       MR. HOPKINS:  The loop really does not
           isolate.  It is just two loops and one pump goes off.
                       DR. KRESS:  And two pumps.
                       CHAIRMAN WALLIS:  The pumps pump through
           both loops don't they?
                       MR. CARUSO:  No, one pump in each loop.
                       CHAIRMAN WALLIS:  They are separate,
           absolutely separate??
                       MR. CARUSO:  Yes.
                       CHAIRMAN WALLIS:  I'm sorry.  But it is
           the same circuit?  The loop is external, and it is the
           external look that you are talking about, and insider
           the reactor vessel, there is just one loop, right?
                       MR. CARUSO:  That's correct.
                       CHAIRMAN WALLIS:  So it is different from
           the usual idea of a loop in a BWR situation.  Well, I
           don't know if we want to go on with this, but
           SAFER/GESTR has very different models for things like
           slip velocity, and so on than TRAC does, and I am not
           quite sure how you use one code to estimate
           uncertainties than another.
                       MR. CARUSO:  Tony, do you have any
           information about the details?
                       MR. ULSES:  Well, what they were really
           trying to do  if I recall was that they were trying to
           sort of bridge the gap between the experimental
           evidence, and down to the SAFER/GESTR methodology. 
           That is my recollection of what they were trying to
           do.  It has been a while since we actually looked at
           the methodology.
                       But the method is certainly not
           exclusively based on the TRAC-SAFER/GESTR comparisons. 
           It is one, I believe, of eight uncertainty terms that
           they add into the results from SAFER/GESTR.
                       CHAIRMAN WALLIS:  I guess what I am
           getting at is the rationale for taking the code of a
           different structure and using it to estimate
           uncertainties in some other code.  I am not quite sure
           how you justify that with some kind of logical thread
           of thought.
                       MR. ULSES:  Well, unfortunately, it is
           difficult for me to discuss what they did in 1986, or
           actually '83, because I wasn't here, but based on what
           I have read in the record, it is basically sort of --
           it is not really discussed, the actual rationale.
                       The assumption really that I made is that
           they are trying to sort of bridge like I said between
           the experimental evidence down to the SAFER/GESTR
                       CHAIRMAN WALLIS:  So they are bridging the
           gap with no rationale?
                       MR. ULSES:  Well, I think the argument
           would have been that the TRAC method would have been
           more accurate, and it would have been based on more
           fundamental principles.  But that is a little bit of
           speculation on my part.
                       CHAIRMAN WALLIS:  Thank you.
                       MR. CARUSO:  The next item that I am going
           to talk about is stability, and the auditor, the staff
           member who did the audit, looked at the implementation
           of Option 1-D to Duane Arnold.
                       And generally he found that it was still
           applicable and still acceptable for use of Duane
                       DR. UHRIG:  Could you describe what you
           mean by Option 1-D?  What is involved?
                       MR. CARUSO:  Well, once again I am going
           to call on my staff because there are a lot of
           differences between the different options.  Tony, do
           you --
                       MR. ULSES:  Yes, sir.  The fundamental
           principle behind Option 1-D is that you make the
           assumption that the reactor will not have an out-of-
           phase instability due to the small reactor size.  In
           other words, it is going to remain tightly coupled.
                       And so all they do really is they apply an
           administratively controlled exclusion region, which
           basically tells the operator that you cannot operate
                       And then they use an on-line monitor, in
           which we are referring to in the second bullet, which
           is basically a backup, which will tell the operator if
           they had an indication of the onset of an instability. 
           And that is basically the option in a nutshell.
                       DR. KRESS:  And that is a core wide
           monitor, and it is not a local monitor?
                       MR. ULSES:  Well, actually what it does is
           that it will tell them whether -- it is actually going
           to give them an indication of an out-of-phase or an
           in-phase instability.
                       DR. KRESS:  But they could see an out-of-
           phase instability?
                       DR. UHRIG:  They could see an out-of-phase
           instability from something.  Actually, what they are
           doing is they are actually doing a calculation.  It is
           not actually looking at the LPM  signals themselves.
                       What is doing is they are taking those as
           an input, and it is using the Odyssey code, which they
           use for calculating the K ratios to actually make a
           prediction of what it would be.
                       So it is not actually looking at the
           signals themselves, which is usually an input into an
                       DR. KRESS:  Does it call for a SCRAM?
                       MR. ULSES:  No, it does not.  It does not. 
           But they rely on the operator to take action in this
           particular scenario.
                       DR. UHRIG:  And the fact that this is a
           smaller core compared to, let's say, LaSalle, where
           there was as I recall a stability incident a few years
           ago, is a favorable indication here that there is less
           likelihood of an instability?
                       MR. ULSES:  Well, what it tells us is that
           there is less likelihood of an out-of-phase
           instability, yes, sir, due to the core size. 
           Actually, in 1988, the LaSalle incident was actually
           a core-wide instability.
                       We had an out-of-phase instability in 1992
           in WMB2 as I recall, which again is a larger size
           reactor, but if you look at all of the evidence that
           we have up to this point, all the evidence will tend
           to suggest that the reactor size is a large
           contributor to whether or not you have an out-of-phase
                       DR. UHRIG:  What are the inputs to the
           stability monitor?  Is it pressure?
                       MR. ULSES:  It is going to take reactor
           flow and reactor power, are the primary inputs to the
           Solomon system.
                       DR. UHRIG:  Is there a core monitoring
           system of any sort of this, a new Trans-lex
                       MR. ULSES:  Yes, sir, it uses in-core
                       DR. UHRIG:  Is this a series of detectors
           at different levels?
                       MR. ULSES:  Yes, sir, and also radially
                       DR. UHRIG:  And what might the total
           number be?
                       MR. ULSES:  I can't recall the actual
           number.  I would say in the order of 50 max, and that
           is an estimate.  It is going to depend obviously on
           reactor size.
                       DR. KRESS:  When you uprate the power and
           up the flow also, does it change the instability
                       MR. CARUSO:  Yes.
                       DR. KRESS:  It does that in an absolute
           sense, but does it on a relative sense, relative to
           percent power and --
                       MR. CARUSO:  Yes, it does, and that was
           one of the findings, was that the instability region
           would increase relatively for this reactor, and
           therefore, the operator, or this finding that I have
           got here, the next finding that I have got here, is
           that operators will have to rely more on this on-line
           stability monitoring system.
                       DR. KRESS:  And do you have to change the
           tech specs also?
                       MR. CARUSO:  I don't know.  Well --
                       MR. ULSES:  This would not impact the tech
           specs at all, Dr. Kress.
                       MR. CARUSO:  But one thing that is
           important is that the operators, because they are
           going to have to rely on this system more, they need
           to be better trained in its use.
                       They need to believe it more and they push
           a button to get the results and the recommendations of
           the system, but they have to start believing that,
           because they will find that the --
                       DR. KRESS:  Does that mean that they
           didn't believe them before?
                       MR. CARUSO:  No, it is a matter of --
           well, how can I explain this.  The calculations to
           determine the power to flow the regions of instability
           are done using a lot of very conservative results.
                       The on-line stability monitor is actually
           using the way the plant operates.  The operators may
           find themselves in an area where the map says you may
           be in trouble, and they will push the button.
                       And they will have the on-line stability
           system tell them, no, your decay ratio is much lower
           than those design engineers told you it was going to
           be, and they may not believe that.  And actually what
           they might do is that they come to not believe the
           Solomon system because it conflicts with the written
           down design details.
                       So we want to make sure that the operators
           use this, and that they believe it when it tells them
           that there is a problem, and that they believe it, and
           that they do something about it.
                       DR. UHRIG:  Now, is Solomon a brand name,
           or is it a specific type of --
                       MR. CARUSO:  Yes, it is the G.E. system
           that is installed at Duane Arnold.
                       DR. UHRIG:  Is this a common system
           throughout many of the BWRs?
                       MR. CARUSO:  I would have to ask G.E. how
           many plants have it installed.
                       MR. ULSES:  It would only be used in the
           Option 1-D plants, which is a very small percentage of
           the fleet.  I believe there are only four plants that
           actually would qualify for Option 1 to the reactor
                       DR. UHRIG:  So because this is a small
           plant, it is a simpler system than is used in the
                       MR. ULSES:  Yes, sir, because they can
           demonstrate that they will have a high likelihood for
           having a core wide instability, as opposed to an out-
           of-phase instability.
                       DR. UHRIG:  There is an indication here
           that the operators are going to have to pay more
           attention to this.  Does this mean an increase in
           their load and the things that they have to do?
           Do they monitor this every hour, every day?
                       MR. CARUSO:  No.
                       DR. UHRIG:  Or when there is an alarm?
                       MR. CARUSO:  No.
                       DR. UHRIG:  How do they know to go push
           the button?
                       MR. CARUSO:  This is not really a matter
           of monitoring on a continuous basis because the only
           time they have to worry about stability is when they
           are in the region where the instabilities might occur.
                       And this would be during a power increase,
           power ascension, or a power descension, when they are
           maneuvering the plant.  Normally when they are
           operating at full power, they will be far away from
           these regions.  So they won't have that as an issue.
                       I don't know offhand what the actual text
           spec requirement is when you are operating at full
           power whether they have to monitor stability to use
           this system.  Do you know, Tony?
                       MR. ULSES:  Well, I guess I would defer
           more to the reactor operators themselves, but I would
           say no, because it wouldn't make a lot of sense to be
           looking at this system when you are at full power,
           because it is not going to give you any information
           that you can really use.
                       But again I would say that I would have to
           defer to Duane Arnold for the answer specifically to
           what they do.
                       CHAIRMAN WALLIS:  Do you have something?
                       MR. BROWNING:  This is Tony Browning again
           for Duane Arnold.  Yes, when you are at full power,
           there is not requirement to do the monitoring.  As
           Ralph said, it is primarily used when you are doing
           start-ups and shut-downs.
                       The system will also automatically
           initiate if there is a dramatic change in power.  For
           example, if a pump trip occurs, the system will turn
           itself on, and will start performing the calculations
           at that time when it sees a Delta-N power or flow of
           greater than a certain magnitude.
                       DR. LEITCH:  Let me make sure that I
           understand then.  What we are saying is that there is
           a region of the power flow map where the operators are
           trained to be sensitive to issues of stability,
           particularly so when they are in single loop; that is,
           when they have lost a recirc pump.
                       And the Solomon system takes no action,
           but just confirms to the operator that he is doing the
           right thing.  And with this core power uprate, this
           region of the power flow map, this region of
           sensitivity is somewhat larger than it would be at the
           current power levels.
                       MR. CARUSO:  That's correct.
                       DR. LEITCH:  Is the Solomon system -- is
           there just one of these, or is there any redundancy in
           the system?
                       MR. CARUSO:  I believe there is only one.
                       DR. LEITCH:  And what about its
           reliability or availability?  Do we know anything
           about that?
                       MR. CARUSO:  QA --
                       MR. ULSES:  Well, again, I would have to
           defer to the Duane Arnold folks, because the system
           has been in use for several years, and based on all
           the information that I have, it is a fairly reliable
           system.  Basically, it is there when they need it.
                       However, for actually any specific
           information, I would say I would have to refer to the
           Duane Arnold folks, because they have been using it
           for several years.
                       DR. LEITCH:  I guess what I am saying is
           that we are saying there is an increased dependence on
           it, and there is a bigger area of the core power flow
           map that may be -- where stability may be a concern.
                       I am just wondering about the reliability
           of the instrumentation if the operator is going to be
           dependent on it to make operating decisions more
           frequently than in the past.
                       MR. CARUSO:  Realize that the -- that when
           we say that the operator is more dependent upon it, we
           mean that during these periods, such as during power
           increases and power decreases, which is a relatively
           small percentage of the time that the plant is
           operating, the operators will have to be more
                       And this is one of those tools that they
           use during those time periods to make sure that the
           plant is operating safely.  It is a relatively small
           window of time, and this is a tool to help them.
                       DR. UHRIG:  Is this a safety grade system?
                       MR. ULSES:  I would say no, but again i
           would have to defer to the Duane Arnold folks for a
           specific answer.
                       MR. BROWNING:  No, it is not, but the
           primary mechanism that the operators use for detect
           and suppress are their in core neutron monitoring. 
           Because we are a 1-D plant, we only see the
           fundamental mode of oscillation.
                       They will see it readily on their core
           wide detection system, and that is their primary means
           of instrumentation that they will use to take operator
           action when they believe they have an instability
                       DR. UHRIG:  So if this system failed, the
           operator still has the means of --
                       MR. BROWNING:  Right.  This is only a
                       DR. UHRIG:  It is a only a backup and a
           convenient system because of being able to push the
           button and get information that would otherwise have
           to be discerned by the operator's knowledge of the
           behavior of the core?
                       MR. BROWNING:  Right.  As Ralph alluded
           to, the exclusion zone on the power flow map has a
           number of conservatisms built into it to account for
           the computer code predictions and other margins.
                       So it is a fairly large area of that
           corner of the power flow map, and a high flow, low
           power, region.  So during the startup, they have to
           maneuver -- normally they try and maneuver around it.
                       Because of the uprate and the size of the
           increase of the region, they are going to be
           challenged to be able to maneuver it.  So we are going
           to have to maneuver through it after the uprate.
                       Hence, the reason why the increased
           reliance on Solomon, because by our tech specs, we are
           only allowed to operate in the region if Solomon is
                       DR. UHRIG:  Is this a tech spec
           requirement that this instrument be available during
           the start up and running through or moving through
           this region, as opposed to maneuvering around it?
                       MR. BROWNING:  What we are allowed is that
           if the Solomon system is not available, there is an
           additional buffer region applied to the exclusion zone
           that we have to apply by the tech specs.
                       So when the back up system is not
           available, we administratively increase the size of
           the exclusion zone, where we are allowed to steady
           state operate.  We are allowed to pass through it, but
           we just are not allowed to stay there for any period
           of time.  But we are allowed to operate through it.
                       DR. LEITCH:  Must Solomon be operable
           prior to taking the load switch to run?
                       MR. BROWNING:  No, it is not.
                       CHAIRMAN WALLIS:  When they operate
           through it what happens?  You do get oscillations, but
           they never get very big; is that what it is?
                       MR. CARUSO:  You won't necessarily get
           oscillations.  It is possible and you might.  These
           are regions where it is --
                       CHAIRMAN WALLIS:  So Solomon tells you if
           you have?
                       MR. CARUSO:  I believe it measures decay
           ration, correct?
                       MR. ULSES:  Well, actually, it is not
           making a measurement at all.  It is using an
           algorithm, and so it is making an actual analysis
           calculation, a prediction of what it thinks the core
           decay ration will be.
                       CHAIRMAN WALLIS:  It is testing something
           about the stability of the magnification?
                       MR. ULSES:  Yes, sir, and I guess I would
           say that I wouldn't expect to see a power loss or
           oscillation during a power ascension.  That is not the
           normal mode of operation for a BWR.
                       DR. UHRIG:  As long as you keep moving
           through it, then there is very little likelihood of
           any significant difficulty?
                       MR. ULSES:  Yes, sir.
                       DR. UHRIG:  And if you stopped while you
           were in this region and operated for a period of time,
           then there might be the possibility; is that the
           implication here?
                       MR. ULSES:  Well, it is an implication,
           but I would say that due to the number of variables
           that you have to put into this analysis that there are
           a lot of things that you would have to do wrong in
           order to have a power oscillation under these
                       DR. KRESS:  I don't think it is related
           how long you are in there, and the time constant for
           setting up this instability is very, very short.
                       MR. ULSES:  Yes, sir.
                       DR. KRESS:  But there has to be a lot of
           other things.
                       DR. UHRIG:  At what power level do you hit
           this regime; is it 20 percent, or 30 percent, 50
                       MR. ULSES:  I don't know.  Do you know the
           actual numbers, Tony?  I don't recall what they are.
                       MR. BROWNING:  I generally recall it in
           terms of load line than actual power level.  The lower
           end of the region is about the 75 percent load line,
           which is about 50 percent power roughly.
                       MR. ULSES:  Right.  It starts off with the
           natural circulation line, and then it works right into
           the power and up to about that power.
                       DR. UHRIG:  And Duane Arnold operates at
           full power all the time, and does not do much
           maneuvering during normal operations?
                       MR. BROWNING:  We only downpower
           occasionally to do required testing.  Our capacity
           factors have been pretty high the last few cycles,
           above 90 percent, and so we stay at full steady stay
           power most of the time.
                       DR. UHRIG:  Thank you.
                       MR. CARUSO:  Any other questions about
           stability?  If not, the next item is the GEXL14
           correlation.  This is a correlation used to determine
           boiling transition and DWR fuel bundles, and
           specifically G.E. 14 and G.E. 12 fuel.
                       And the staff reviewed the development of
           this correlation, and during the course of the review,
           we identified that G.E. had used some data generated
           by a code called COBRAG, which is the G.E. version of
           COBRAG, or COBRA, to add to the GEXL14 database to use
           in the correlation.
                       We are not entirely convinced of the
           appropriateness of this data, and we are conducting
           discussions with GE right now about whether it is
           appropriate and whether it is acceptable, and what has
           to be done as a result.
                       CHAIRMAN WALLIS:  Code generated data?
                       MR. CARUSO:  That's why we have a concern.
                       CHAIRMAN WALLIS:  Well, maybe this is the
           new world, and codes generate data.
                       MR. CARUSO:  That's why we have a concern.
                       CHAIRMAN WALLIS:  When you say in boring
           transition, you mean transition to  --
                       MR. CARUSO:  Dryout.
                       CHAIRMAN WALLIS:  DNB; is this what we
           call DNB?
                       MR. CARUSO:  No, it is DNB.  It is dryout.
                       CHAIRMAN WALLIS:  So it is reduced heat
                       MR. CARUSO:  Yes.  We also did a review of
           core design methods, and the reviewer there determined
           that the methods that are being used for cord design
           are appropriate, and we also looked at the Safety
           limit MCPR which we determined were being used
                       DR. BOEHNERT:  Ralph, before you leave
           that, on the GEXL14, what is the outcome of this if
           you guys don't like what they are doing by the code
           generating data?  What happens then?
                       MR. CARUSO:  It would be possible that
           -- I mean, I don't want to get into the details of the
           discussion between us and G.E., okay?  Some of the
           potential outcomes are that we could possibly approve
           the use of COBRAG to generate data for GEXL.
                       I think that would require us to do a
           review of the code and the way that it is applied. 
           Another possibility is that G.E. could remove the data
           from the database, and that would cause them to take
           some sort of a penalty in using the correlation, and
           it would increase uncertainty by a certain amount, and
           that would be applied.
                       DR. KRESS:  What data are we talking about
           that this COBRA is generating?
                       MR. CARUSO:  It is trying to predict
           dryout in a fuel bundle.
                       MR. KLAPPROTH:  Ralph, can I make a
           statement?  This is Jim Klapproth.  So that there is
           no confusion, there is a lot of test data on GEXL14. 
           Basically, it is an issue of the power shape.  We do
           a lot of thermal-hydraulic testing to develop
           hydraulic very brisk bundles, using some power
                       What COBRA does is then extend that
           database for a different power shape.  So it is not
           just that we have the code data.  We have a bunch of
           -- thousands of data points from hydraulic testing,
           and we are just extending that data to predict the
           response, the GEXL correlation to other power shapes.
                       DR. KRESS:  I am not sure I understand how
           the power shape affects this at all.  With BWRs, you
           have the channels, and so it is not radiation heat
           transfer, and --
                       MR. KLAPPROTH:  Well, as we move through
           the cycle, our power shape changes, and it will move
           from a low of --
                       DR. KRESS:  I understand that, but I don't
           understand what that does to the correlation at all.
                       MR. CARUSO:  The correlation takes into
           account the nominal code signing shape and whether it
           down skews or up skews, where the power has peaked
           higher at the outlet or peaked higher at the bottom of
           the channel.
                       DR. KRESS:  But doesn't that just
           determine the location of where you can do these
           things?  It doesn't affect the correlation at all.
                       MR. CARUSO:  I have my experts here to
           give you some more --
                       MR. ECKERT:  I am Tony Eckert from the
           Reactor System Branch.  Usually when they develop a
           correlation, they take data in what they consider the
           operational range of the fuel, and so they look at co-
           signed data basically and all down-skewed data, or
           they look at the power shape at the bottom end of the
           core and at the top end of the core.
                       And then they correlate to all that data,
           and typically what every vendor does, okay?  It is
           typically what every vendor does.  And in this case in
           particular, it is important in the top part of the
           core because this fuel has poplin rods (phonetic) that
           stop about 8 feet up the core.
                       So you would really like to know what is
           going on up there with regard to all kinds of face
           changes going on and so forth.  So what we found is
           that there was no data taken specifically in that part
           of the core.
                       And so what in essence they did is that
           they used COBRAG to predict the behavior of the fuel
           in what we consider to be a very critical region of
           the fuel, which we had not seen there before.
                       DR. SCHROCK:  Isn't the correlation
           necessarily employment a subchannel analysis
           methodology, which becomes an integral part of the
           correlation?  Isn't that the way that this works?
                       MR. ULSES:  Well, it has the concepts of
           a subchannel code because it does attempt to deal with
           the radio power distribution.  But what we have seen
           in the past is that these correlations have always
           been based strictly on experimental data that was
           taken from their facility.
                       But this is the first time that the staff
           has specifically encountered the use of a code to try
           and augment the data.
                       DR. SCHROCK:  The experiment is incapable
           to giving localized thermal-hydraulic conditions
           within the rod bundle, and in order to accomplish the
           correlation, I think there is a need to operate a
           subchannel analysis code, together with -- and put
           that together with the experimental data to get what
           is the GEXL correlation.
                       DR. KRESS:  That is exactly what was
           confusing me.
                       DR. SCHROCK:  So it is a little unclear to
           me what the new thing is that COBRA is doing.  What is
           the subchannel analysis code that normally is a part
           of the G.E. correlation scheme, and how this COBRA
           application different from that?
                       MR. ULSES:  Well, actually, Dr. Schrock,
           I would say that what they do is that they test an
           actual prototypical bundle and use electrical heaters.
                       And when they do that, they can actually
           vary the actual local subchannel conditions in the
           experimental facility itself.  So they are relying on
           the experimental data.
                       DR. SCHROCK:  But there is no way in the
           world that they would have sufficient instrumentation
           to know thermal-hydraulic conditions locally within
           the rod bundle and throughout the bundle?
                       MR. ULSES:  Well, that is not what they
           are after.  All they are after is they are after --
           when they see the boiling transition on the thermal
           couples, with that, they can tell at what axial and
           radial location that happens, and that is what they
           are trying to find out out of this correlation.
                       And they are using information from the
           in-let of the channels; is that right?
                       MR. CARUSO:  That's right.
                       DR. SCHROCK:  And correlated against what?
                       MR. ULSES:  It is correlated against the
           in-let conditions of the fuel channel, which is a
           known quality.
                       DR. SCHROCK:  I think you need to clarify
           what the scheme is, and then discuss it in terms of
           this COBRA TRAC generated data.
                       CHAIRMAN WALLIS:  Is there some way we can
           get the evidence to Dr. Schrock so that he can look it
           over and so that he can understand what is really
           being done?
                       MR. ULSES:  Well, we don't have it here
                       DR. SCHROCK:  I thought what I did hear
           and what I am hearing and that I understand it to be
           is that it is not consistent with what I hear.
                       MR. CARUSO:  I don't know how much time
           you want to spend on explaining GEXL14 and now it is
                       CHAIRMAN WALLIS:  Well, if it is
           important, and I don't know what yet is important, and
           what are the important issues in uprates, but if it
           turns out that this is an important issue, then it
           should be resolved.
                       MR. CARUSO:  We don't think this is an
           important issue for power uprates, per se.  It is an
           issue for G.E. 14 and G.E. 12 that is used wherever it
           is used.
                       But we don't think that this is a power
           uprate specific issue.  This is one of those issues
           that I mentioned which has generic applicability.
                       CHAIRMAN WALLIS:  Unless in some way the
           power uprate was pushing the limits of applicability
           of some method.
                       MR. CARUSO:  That we don't think is the
           case here.  I'm sorry, Tony.
                       MR. ULSES:  Well, what we are seeing with
           these new G.E. fuel bundles is that they have more
           thermal margin, and they are basically using that for
           these power uprates.
                       So in a sense, it is hard to say in actual
           real specific terms whether the power uprate itself is
           actually driving this, or whether, say, an operator
           who is not using a power uprate might seek to use some
           of this margin to minimize the number of bundles they
           have to buy, for example.
                       So I guess I would agree with you that it
           is not a power base specific issue, but it has
           implications in that direction.
                       MR. CARUSO:  Let us talk about what we can
           provide to you, and can I get back to you a little bit
           later in the day on this?
                       CHAIRMAN WALLIS:  Sure.
                       DR. SCHROCK:  Is this the new fuel?
                       MR. CARUSO:  Yes.
                       DR. SCHROCK:  This is 14?
                       MR. CARUSO:  Yes.
                       CHAIRMAN WALLIS:  There is nothing in your
           list about neutron flux here?  Are you getting enough
           power to operate?  This is achieved presumably by
           greater neutron fluxes at various places, and this
           changes the fluents and things like value dense?  You
           have not said anything about those issues.
                       MR. CARUSO:  No, vessel fluids.  Is that
           what you were --
                       CHAIRMAN WALLIS:  Whatever, but there is
           greater neutron flux associated with presumably
           greater power.
                       MR. CARUSO:  That's correct.
                       CHAIRMAN WALLIS:  And in some places,
           depending on how they flatten the power into the flux
           and so on.  Are there any effects that need to be
                       MR. CARUSO:  I believe that that was
           considered to some extent in the reactor core design
           issue.  Ed, did you look at flux shapes and flux
                       MR. KINDER:  This is Ed Kinder, Corrective
           Systems Branch.  In our review of both the equilibrium
           cycle, which is full G.4. 14 core, and the transition
           cycles, which go from the current fuel design, we
           looked at flux shapes and power shapes.
                       And as was mentioned, the G.E. 14 bundle
           is designed with more thermal margin.  It is also
           designed so that the bundle of power itself, and the
           radial core power is flatter.  And each cycle has a
           design enrichments, vendable poisons, and core
           loading, to essentially flatten the power.
                       One of the neutron flux is higher, and the
           vessel fluence is an issue which is also looked at in
           this area.
                       DR. FORD:  Could I ask a further question? 
           There is a whole range of materials degradation issues
           which could potentially impact on this; fluence use
           corrosion, vibration, and there was mention of the
           flux at the core shroud, and pressure vessel.  Are
           these going to be audited at all?  Are we going to
           hear about that today?
                       MR. ELLIOTT:  Excuse me.  This is Barry
           Elliott, of the Materials and Chemical Engineering
           Branch of the NRR.  The issue of neutron irradiation
           and embrittlement affects the stainless internals and
           the alloy steel pressure vessel.
                       For the pressure vessel, alloy steel
           pressure vessels, the neutron fluence affects the
           pressure temperature limits and the upper shelf
                       But those evaluations are evaluated by our
           staff and calculations are done in order to assure
           that the pressure temperature limits in the upper
           shelf energy for the reactor vessel meets Appendix G,
           10 CFR 50 requirements.
                       As far as the internals are concerned, the
           BWR VIP program is carried forward, and whatever the
           program has for the fluence and for the vessel would
           be the program that we would use for the power uprate.
                       MR. CARUSO:  We have existing programs in
           place that account for whatever fluence is generated
           by the vessel, by the core, on various structural
           components, whether it is internal or the vessel, and
           those are accounted for.
                       At the higher power levels the flux or the
           fluents accumulates faster, and that is taken into
                       DR. FORD:  And would the current VIP
           methodologies attack, for instance, a radiation that
           is cracking at H-4 weld?  Would it attack that, and 
           fluences be expected to have the power uprate and
           license renewal?
                       MR. ELLIOT:  The BRR VIP programs are what
           they are.  I mean, they were approved for -- and as
           you run the plant, they are approved for the life of
           the plant.
                       We have approved power uprates and we have
           approved license extension 20 years so that it is
           built into the program.
                       DR. FORD:  So we are taking into account
           the synergistic effect of increased fluents with
           license renewal?
                       MR. ELLIOTT:  Yes.
                       DR. FORD:  Plus, increased flux?
                       MR. ELLIOTT:  The documents are evaluating
           the impact of fluents, and have an inspection and
           repair programs accordingly.
                       DR. FORD:  And how about fluence with
           accelerated corrosion and vibration use corrosion,
           which have been problems?  For instance, Susquehanna
           and Calloway power outrates?
                       MR. ELLIOTT:  I have to say that I don't
           know all the details that you are describing, but with
           irradiation, and since there is this stress corrosion
           and cracking issue, it is built into the BWR VIP
                       DR. FORD:  And that is taken into account
           in the VIP documents?
                       MR. ELLIOTT:  Radiation assisted stress
           corrosion cracking is.
                       DR. FORD:  Yes, but I am talking about
           fluence assisted corrosion?
                       MR. ELLIOTT:  I would have to look that
           up.  I don't have that information.  With flow
           assisted corrosion, I would have to find out how we
           evaluated it as part of the BWR VIP program.  I would
           have to look at that, at flow assisted corrosion.
                       DR. FORD:  Okay.  And the zircloid-F
           swelling be a problem?
                       MR. ELLIOTT:  That is considered.  It is
           part of the BWR VIP program.
                       MR. CARUSO:  You were asking about
           zirculoid corrosion of fuel cladding?
                       DR. FORD:  Yes, cladding.
                       MR. CARUSO:  Fuel cladding is considered
           as part of the fuel design, and the fuel design --
           well, actually, that is a matter of fuel burnup.  And
           fuel burnup limits are not changing as a result of the
           power uprates.
                       So the fuel that is rated to a certain 
           burnup level will not be allowed to go any higher than
           that as a result of the power uprates.  So we are
           working within the existing database, and it doesn't
           matter if they raise the power.
                       They might burnout fuel elements faster,
           but they still can't burn them beyond where they are
           currently allowed to burn them and where the
           experienced database ends.
                       DR. FORD:  I am showing my ignorance on
           this particular part, but when they come up with a
           design criteria, that was made at the time of
           licensing, and maybe we didn't understand some of the
           phenomena that have since come to the fore.
                       MR. CARUSO:  Are you talking about in
           terms of fuel?
                       DR. FORD:  Fuel, or ISEC, for instance. It
           was not a known phenomena when these things were --
           when the design basis was --
                       MR. CARUSO:  I can't address the issue of
           the ISEC, but I can talk about fuel, and I do know
           that we are not using fuel acceptance criteria now
           that were used in 1972 when the plant was licensed. 
           We are using current knowledge-based acceptance
           criteria, and current standards for fuel.
                       DR. FORD:  Is there going to be a
           presentation on these specific TLAs later on today or
                       MR. CARUSO:  No, not on fuel.  No.
                       DR. FORD:  Well, on any materials or
                       MR. HOPKINS:  Well, that's why we had
           Barry Elliott here to respond to questions.  We didn't
           have a specific presentation planned for that area.
                       DR. FORD:  It is a fairly important area
           though isn't it, given the fact that for the last 20
           years we have had a pretty abysmal record in terms of
           materials integrity.  We have now started to change
           two things, license renewal and power uprate, which
           can be synergistic.
                       We are going to be attacking those two
           things in that format, in that synergistic format,
           aren't we?
                       MR. ELLIOTT:  I would say that this is a
           power uprate portion, and the fluence for the power
           uprate is going to be much less than the fluence for
           BWRs who have license extension.  I mean, that's just
           the way it is going to be.
                       DR. FORD:  I guess my question --
                       MR. ELLIOTT:  Ultimately, we are going to
           have both added on, and when get to our license
           extension, we will address both of those things when
           it occurs, but right now we are just power uprate.
                       And I think the BWR VIP program would
           encompass all these issues that have come up within
           the last couple of years, and would not be impacted
           significantly by the power uprate.
                       DR. FORD:  I guess my frustration is that
           I keep hearing these terms, but I don't see any data
           and that is my frustration.
                       MR. CARUSO:  Would you like a presentation
           on fuels?
                       DR. FORD:  No, not particularly fuels, but
           any materials of construction.  I would love to hear
           an analysis of the expected degradation, time
           dependent degradation of the materials of
           construction; core-shroud, pressure vessel, weldments,
           as a function of increased power uprates.
                       CHAIRMAN WALLIS:  Well, I guess it applies
           to all of these issues, and we keep being told that
           the methods are being used approximately, and it would
           be good if there could be a technical presentation or
           something, and where here is a graph of X versus Y.
                       And this is what you have without power
           uprates, and this is where you might be pushing some
           limit, and this is where you go with the power
           uprates, and sort of a quantitative comparison in some
           technical terms.
                       MR. CARUSO:  Actually, I believe you are
           going to get some of that later on today from GE.
                       CHAIRMAN WALLIS:  Okay.  We will look

           forward to that.
                       MR. CARUSO:  Let me see.  My last slide is
           conclusions, and unfortunately, Dr. Wallis, I am going
           to give you a conclusion without any details.  That
           the approved methods continue to be used appropriately
           at the uprated power levels.
                       That the GEXL14 correlation database
           evaluation issue we are continuing to discuss with GE
           and the licensee, and we hope to resolve that soon. 
           We would like to resolve that as soon as possible.
                       We intend to continue to do these audits
           for Dresden and Quad Cities later on, I believe, this
           month, and for Clinton later on in the year once the
           Clinton application has been received.
                       CHAIRMAN WALLIS:  I don't think it has
           come in yet has it?
                       MR. CARUSO:  And we find these to be
           particularly useful.  And we will probably vary the
           areas that we do audits on.  This time we did
           SAFER/GESTR, and we did stability.
                       Dresden and Quad Cities will probably do
           a different stability option, because I believe that
           they may be using a different stability option.  We
           will look at maybe ATWS, and we will look at other
           scenarios.  We will look at other issues.
                       CHAIRMAN WALLIS:  I think we are going to
           ask questions about ATWS this afternoon, and is that
           when we will get the answers?
                       MR. CARUSO:  I see G.E. nodding yes.
                       DR. UHRIG:  This work that you have done
           so far has been exclusively Duane Arnold?
                       MR. CARUSO:  It has been focused on Duane
           Arnold, but realizing that some of the things that we
           look at have generic applicability, like the GEXL14
           correlation is not just for Duane Arnold.
           It applies to anyone who has G.E. 12 or GE 14 fuel.
                       CHAIRMAN WALLIS:  And the follow on
           plants, Duane Arnold, as I understand, is one of the 
           smallest plants of BWRs, and if not the smallest, and
           then the next sort of size up is the Quad Cities, and
           then it goes on to Clinton as the biggest.
                       And size then, is there anything else
           besides stability, core stability, that is related to
           size?  Are there any new issues that you expect to
           come up in the later plan reviews that is not inherit
           other than the difference in the stability issue?
                       MR. CARUSO:  Off the top of my head, I
           can't think of anything, but possibly ATWS
           performance, or ATWS response, might be an issue. 
           Containments.  Containment is probably one area where
           we should look because that is very plan specific.
                       The relationship between the size of the
           containment and the decay heat loads is very much plan
                       DR. UHRIG:  It is pretty much related to
           whether it is a Mark III or Mark II?
                       MR. CARUSO:  I think it probably depends
           on whether it is a Mark I, Mark II, or Mark III, but
           it also depends on the actual size, because I don't
           think that all Mark IIs are the same size, or the same
           sized relative to the power well.
                       CHAIRMAN WALLIS:  If all these methods
           continue to be used appropriately, how much uprate is
           tolerable, and what limits -- when do we first hit a
           limit if we set an uprate to 30 percent or 40 percent,
           50 percent?  When do we say you can't go any further?
                       MR. CARUSO:  I have a sense of deja vu
           when I hear that question.
                       CHAIRMAN WALLIS:  Well, you see, the 
           methods can still be used appropriately.
                       MR. CARUSO:  Well, I think you will get a
           chance to ask G.E. that question this afternoon, and
           I think you should ask them that, because we have
           asked them that question and they tell us, well, the
           first thing or limit that you run into is the turbine
           because you can't use the power.
                       CHAIRMAN WALLIS:  So you put in a bigger
           turbine.  That is not really an issue.
                       MR. HOPKINS:  Let me mention for Clinton
           briefly.  I mean, they have not made their application
           yet, but they are going for 20 percent, and they will
           be basically changing out the high pressure and low
           pressure turbines, and getting a new main power
           transformer, and new reserve alt transformers, and
           doing feed water heater work, and doing main generator
           work for more efficient cooling.
                       And doing main condenser work, and all
           this is a constant pressure uprate, but all of this is
           try to get 20 percent, and it is a substantial amount
           of modifications.
                       CHAIRMAN WALLIS:  It is not really an
           issue with the right to safety.
                       MR. HOPKINS:  I know, but it has an effect
           on dollars and now much you spend for how much you
                       DR. KRESS:  I think the question is more
           philosophical along these lines.  As you do things
           like the power uprates, and license extensions, et
           cetera, you do change the margins.
                       And the Chapter 15 margins on certain
           figures of merit and even risk acceptance margins on
           things like CDF and LERF, they are changed.  Now, the
           question that I would have is that I think there is a
           question to ask, and that is, is there a significant
           decrease in the margins is a question that one would
                       Well, what is meant by the word
           significant in there?  Is the view that as long as you
           meet these figures of merit at all, then the change or
           decrease in margin is acceptable, and thus not
           significant.  Is that the staff's philosophical view
           on this, or is there more to it than that?
                       MR. CARUSO:  I guess I am jumping to the 
           middle of Donnie Harrison's presentation, but the
           simple answer to that is yes.  We have limits that
           come from regulations, and we have a 2,200 degree
           limit, and we have limits that come out of approved
           topical reports, where we approve methodologies.
                       DR. KRESS:  And as long as you meet those
           limits --
                       MR. CARUSO:  As long as you meet those
           limits, that is the important thing.
                       CHAIRMAN WALLIS:  So that is the answer,
           it is not really a philosophical question.  You can
           keep operating until you hit one of those limits.
                       MR. CARUSO:  Until you hit one of those
           limits, yes, and the question is which limit are you
           going to hit first.  I mean, there may be other limits
           that are not necessarily regulatory limits.
                       I imagine that there are probably internal
           design constraints on fuels that people might run into
           before they run into any regulatory limits.
                       CHAIRMAN WALLIS:  But 20 percent seems to
           be according to the story here so easy, you wonder why
           it is not 30 percent.
                       MR. CARUSO:  I think that is what I was
           trying to answer.  I think there are practical
           considerations for how much you can get.
                       CHAIRMAN WALLIS:  So apparently there is
           no limit on the reactor side.
                       MR. CARUSO:  Not yet.  My speculation
           would be that they will probably run into containment
           limits first, because that is not something that is
           changeable, and I have seen the curves for containment
           performance, and they are very close to the limits.
                       CHAIRMAN WALLIS:  And what has changed
           them?  Why is it that years ago these were designed,
           or they were approved at a lower power level?  Has
           there been some great new insight into fuel design or
           materials behavior, or thermal-hydraulics which makes
           it now possible to uprate by 20 percent?
                       MR. CARUSO:  I am not sure which Tony
           mentioned it, as there are three Tonys in the room who
           have spoken.  One of the Tonys mentioned the fact that
           we have gone through -- that G.E. has gone to this
           better fuel.
                       CHAIRMAN WALLIS:  Is it better fuel?
                       MR. CARUSO:  It is better fuel.  It is
           designed in a way which allows them to get more steam
           out of this bundle.
                       CHAIRMAN WALLIS:  Better fuel in terms of
                       MR. CARUSO:  Yes, part-length rods,
           cleverness in using thermal-hydraulics.
                       DR. FORD:  My guess is that you are going
           to come across a materials degradation problem, which
           is going to be limiting, and it scares the pants off
           me when I think --
                       DR. KRESS:  Well, the trouble is that
           there is a very limited or lack of knowledge on how
           power affects what you are talking about, except with
           the acceptance of the fluence problem.  But the other
           degradation problems you can't relate to power very
                       MR. CARUSO:  I know about the fluence
           issue because the fellow that does the fluence
           calculations used to work for me, and he educated me
           on this.  And it is -- we do account for that.
                       DR. KRESS:  Yes, it is fairly
                       MR. CARUSO:  They have this bucket, and
           they keep throwing fluence into it every year, and
           they have to measure the height of the level in the
                       DR. KRESS:  That's exactly right.  It is
           pretty straightforward.
                       MR. CARUSO:  And if you raise the power
           the bucket gets full faster, and there is a limit on
           how much you can throw in the bucket.  And if they run
           out of space, that's it.  You have to go out and kneel
           the vessel or they will have to do something else.  I
           don't know what.
                       DR. KRESS:  And then when you get to other
           materials degradation issues, like intragranial or
           stress corrosion cracking, that is hard to relate that
           to power.
                       MR. CARUSO:  That I don't know.  That is
           out of my area of expertise.
                       CHAIRMAN WALLIS:  The thermal-hydraulics,
           the outside of the fuel is at about the boiling
           temperature and the heat transference is so good.  And
           if you go to a higher power, does that mean that you
           get a higher set of center line fuel temperature, or
           is it something done to make that better?
                       MR. CARUSO:  That is a good one.  I don't
           know the answer.
                       CHAIRMAN WALLIS:  It is a big temperature
           drop from on-line fuel to the wall, a huge drop.  What
           is happening inside this fuel at these higher powers?
                       MR. CARUSO:  I don't know what center line
           fuel tempers do.
                       CHAIRMAN WALLIS:  Is that another
           criterion of some sort, that it cam go to any value it
                       MR. CARUSO:  As far as I know, that is not
           a regulatory criteria, but I would imagine it is
           probably a design criteria that the fuel vendor uses.
                       DR. UHRIG:  But it pushes you towards  the
           2,200 limit --
                       MR. CARUSO:  Probably, yes, higher lineal
           heat generation, right, is going to reduce the margins
           if you assume that everything else stays the same, and
           it is going to reduce margins, yes.
                       CHAIRMAN WALLIS:  And it makes products
           more mobile inside the fuels so they can move around
           and accumulate in places?  And maybe move to the
           outside and maybe holds the cladding?
                       DR. KRESS:  That is one of our questions,
           is does the gap inventory increase, for example, and
           the thinking was that thermal diffusion might -- in
           the first place, you are going to have more inventory
           because of the higher uprate of some of the gap --
                       MR. CARUSO:  Actually, inventory depends
           on burnup.
                       DR. KRESS:  Yes.
                       MR. CARUSO:  And the burnup limits hasn't
                       DR. KRESS:  Yes, but normally you reach
           the equilibrium with some of the shorter lives, and
           things that you worry about, like the iodines, and the
                       MR. CARUSO:  Maybe the distribution will
           be slightly different.
                       DR. KRESS:  But I don't know of any data
           that relates to center line temperature, operating
           temperature, to the gap.  For example, where you have
           might have thermal diffusion pushing things in that
                       So that was the nature of one of the
           questions that we asked, is there some evidence or is
           there a need for additional research on what is
           actually in the gap that relates to these higher
           temperatures of the fuel.  And then the higher burnup.
                       CHAIRMAN WALLIS:  Well, this has been done
           before and we know all the answers.
                       DR. KRESS:  Right, or is there some data
           that tells us not to worry about it?  And is it
           important to know what is in that gap from a risk
                       MR. CARUSO:  I don't have an answer for
           you on that.
                       MR. HARRISON:  But we will have a slide
           for that half-way through mine.
                       DR. KRESS:  Okay.
                       CHAIRMAN WALLIS:  You are taking too long,
           Ralph, and we need to move on.
                       MR. CARUSO:  I can talk all day.
                       CHAIRMAN WALLIS:  But talking isn't the
           issue.  It is transferring information.  We could all
           talk.  Try to get a sufficient transfer of
           information.  Would it be best to move on, you think?
                       MR. CARUSO:  I think so.
                       CHAIRMAN WALLIS:  I'm sure that we will
           come back to many of these questions when we talk to
                       MR. CARUSO:  I think so.  I would like to
           hear G.E.'s answers to some of these questions.
                       CHAIRMAN WALLIS:  We thought you had asked
           all these questions before and didn't get answers.
                       MR. CARUSO:  A lot of them, yes, but some
           of them -- the fuel center line temperature is one
           that I have not heard before.
                       CHAIRMAN WALLIS:  So maybe we should move
                       DR. LEITCH:  Just before we leave, I would
           like to go back to the Solomon and the instability
           issue for just a moment.  If the operator lacks
           confidence in this system, it is usually with some
           justification if the operator lacks confidence.
                       Are we saying that this is a training
           issue or is Solomon's ability to predict instability
           in question?
                       MR. CARUSO:  I am not sure I would say it
           is necessarily an ability of the system.  I used to be
           an operator, and I am a former Navy operator, and I
           think about the instruments that we used all the time;
           and you watched them go up and you watched them go
                       You believed them because they moved a lot
           and you had ways to check them.  The ones that you
           never really believed were the ones that sat there in
           the corner and never used until the one time that they
           went off, and you said wait a minute, that never goes
                       And you hit it hard.  You hit it with
           something, and make sure that there is nothing wrong
           with it.
                       DR. KRESS:  And which ACRS member is that?
                       MR. CARUSO:  The classic example is the
           water level instrument in a PWR.  You know, for 30
           years it reads peg high, and then one day is comes
           down off the peg, and the operator says, wait a
           minute, no, no, no, that can't be.  It is never like
           that.  And they don't believe that they have lost the
           water level in the core.
                       CHAIRMAN WALLIS:  That's the problem. They
           don't believe.
                       MR. CARUSO:  But I don't know how you can
           solve that problem except to educate the operators to
           think about what it means, and say, well, maybe there
           is some other way that I can check this.
                       And as the Duane Arnold people say, this
           system is not the only way that they use to determine
           instability.  They are supposed to use this system to
           tell them when they are likely to have an instability,
           and then they are supposed to go look at the actual
           power range instruments to determine whether they do
           have an instability.
                       DR. LEITCH:  I seem to recall that Duane
           Arnold has a plant specific simulator.  Is Solomon
                       MR. CARUSO:  I see Tony noddiNg his head
           yes.  I don't know how to address your -- I think it
           is a valid question.  It is something that we really
           have brought up as part of this, and we think it will
           be up to the licensee to try to get the operators to
           use the equipment that they have got.  And the
           operators do strange things.  I know because I used to
           be one.
                       DR. LEITCH:  I know that it is difficult
           getting folks to rely on instrumentation that is
           normally out of range, let's say.
                       MR. CARUSO:  Right.  But if that
           instrumentation is reliable and believable when it
           comes down into range, then the operators ought to
           believe in their instrumentation.
                       DR. LEITCH:  They should.  And I guess my
           question is whether it is believable or is it
           something that if it doesn't work, then we are
           confusing data in front of the operators.
                       MR. CARUSO:  We think it is believable. 
           We think it is good instrumentation.  We think it
           should be there.
                       DR. LEITCH:  Okay.  So training the
           operators to rely on that when it is in range?
                       MR. CARUSO:  Yes, to use it.
                       DR. LEITCH:  Thanks.
                       CHAIRMAN WALLIS:  Would it be best to take
           a break now or move on?
                       MR. HOPKINS:  This would be a good time.
                       MR. HARRISON:  We will be moving on to PRA
           issues next.
                       CHAIRMAN WALLIS:  How long is that going
           to take?
                       MR. HOPKINS:  Oh, 2 or 3 minutes.  We
           could just mow through it.
                       CHAIRMAN WALLIS:  Let's take a break until
                       (Whereupon, the meeting was recessed at
           9:51 a.m., and resumed at 10:00 a.m.)
                       CHAIRMAN WALLIS:  The meeting will come to
           order.  We are looking forward to hearing about risk
           in the next topic.
                       MR. RUBIN:  Good morning.  I am Mark Rubin
           from the PRA branch.  I have someone new to introduce
           you to this morning, Donald Harrison, who joined our
           branch, the PSA branch of NRR a number of months ago.
                       And sine the previous reviewer, Sam Lee,
           has been made an offer that he can't refuse, he has
           moved on to another assignment, and Doug Harrison will
           be one of the people working on the risk PRA reviews
           for the power uprate plants.
                       MR. HARRISON:  I just want to let you know
           what the scope of my discussion will be, will be to
           walk through first just some slides on Duane Arnold,
           and let you know the information we received from
           them, the topic areas.
                       And then we will proceed right into the
           topics and the six questions that were provided by the
           ACRS.  We are still reviewing Duane Arnold.  I just
           want to make it clear that this presentation part is
           essentially the Duane Arnold information that we have
           received, either directly in their submittal, or in
           response to questions the staff has asked.
                       I do want to put us into a perspective
           that Duane Arnold in their submitted as made it very
           clear that this was not submitted as a risk-informed
           licensing action.  However, the staff is reviewing it
           using the criteria of Delta-CDF and Delta-LERF that is
           Reg Guide 1.174.
                       If we look at the question on PRA quality,
           it is really a question of do you reflect the design
           and operation of the plant, and Duane Arnold has
           submitted that it does reflect their plant
                       They have been through a BWR owners group
           peer review, and the staff is considering if we need
           to take a look at the peer review to get a good feel
           for the areas that we typically look at.
                       DR. KRESS:  Is that peer review different
           from the certification process?
                       MR. RUBIN:  No, it is the identical BWR
           certification peer review, yes.
                       MR. HARRISON:  There are four areas that
           we typically look at; initiating event frequencies,
           and success criteria, component reliability, and
           operator actions.  So we will walk through those four,
           and the responses that Duane Arnold has provided.
                       On initiating event frequencies, Duane
           Arnold doesn't expect any changes to that frequency
           for those things that would cause reactor SCRAMS or
           set point pump failures, and that type of thing.
                       They have stated that they feel that they
           have adequate margin so that they don't expect there
           to be any kind of an increase in that area.  They are
           making modifications and design changes to the -- I
           think it is the main transformer, and some electrical
                       And that is to capture margin or extend
           the margin that they already have, and because of
           that, the potential for, say, a plant loss of all site
           power is believed to be not effected either.
                       DR. LEITCH:  Are they taxing the margin in
           BOP equipment such as condensate pumps, reactor feed
           pumps, such that -- well, let me come at my question
           another way.
                       Often times a plant has enough margin in
           those that when you are operating at a hundred percent
           power that you can lose a major auxiliary like that,
           a condensate pump, for example, and get down under the
           capacity of the remaining condensate pumps, and ride
           it out without a SCRAM.
                       Whereas, it seems to me that if you are
           operating further up on the capability of those major
           auxiliaries that if you lost one of those that you
           might be more inclined to take a SCRAM.
                       And I guess I am wondering is that the
           case as you see it at Duane Arnold?
                       MR. HARRISON:  At Duane Arnold?  I don't
           -- from my part of the review, I have not seen that. 
           I know at other plants that require, say, adding
           another operating condensate pump to get the flow they
           need -- and then you may have a run back design change
           that you have had to install, that would be an area
           where you would then have to look at what is the
           effect of a spurious trip, and that would be a new
           condition.  And I don't believe that Duane Arnold has
           that condition.
                       DR. LEITCH:  But by saying there are no
           changes in the initiating event frequency, you don't
           see any change in that?  For example, in the SCRAM
           frequency, in the situation that I described.
                       MR. HARRISON:  Right.  The projection is
           that the SCRAM frequencies would stay essentially
           where they are at.
                       DR. CRONENBERG:  What about small break
           LOCA, like Susquehanna and the recirculation line
           after they had the power uprate there?  The initial
           interpretation of that even was that it was a flow
           induced vibration effect, and hence, in the
           recirculation line, and that caused that rupture in
           the recirculation line.
                       Also, to come back to Peter's question,
           all of this due to corrosion, and this is a direct
           cycle plant, and the main steam line is higher post,
           and did you find it that there was a no change
           anticipated, and do you find that a little suspect?
           How did they calculate the small break LOCA
                       MR. HARRISON:  I don't believe -- and may
           I can ask Duane Arnold to correct me if I am wrong
           here, but I don't believe that they necessarily went
           out and recalculated new LOCA numbers, considering an
           increased flow for like -- well, the argument on the
           primary system LOCAs is that you have got condition
           monitoring programs, and you have got a fact program.
                       And those programs are being relied on to
           maintain the system.  Now, you may expand that program
           monitor for that, but I don't believe that would
           affect the LOCA numbers.
                       MR. ECKERT:  This is Gene Eckert from G.E. 
           Can I just make one comment and we will talk again
           this afternoon, but in the Susquehanna case, they made
           two changes, and a little contrary to what our
           standard programs have been, that they came in with a
           power uprate.
                       And with an increase in their maximum core
           flow allowed for the plant; and then the things that
           they got into appeared to be associated with that
           increase in core flow above where they had run before.
                       All the plants like Duane Arnold and the
           ones that you saw on the list up here today are coming
           into the uprate program without increasing their
           maximum core flow, and they are keeping the same
           limits on what their external drive loop flows will be
           in the recirc loops.
                       DR. KRESS:  Speaking of incidents, has
           there been any look at past upgrade uprates?  Of
           course, none have been as significant as this, but to
           see if -- well, for example, the AEOD people, would
           they have looked to see if there was any change in
           these initiating event frequencies due to the uprate?
                       I suspect that he experience has been the
           other way, and it has gone down, but for other
                       MR. RUBIN:  We have not looked directly. 
           I did talk to the AEOD section chief, Steve Mayes, and
           his view was that there wasn't going to be enough time
           history to establish anything.  So we have not
           proceeded on that.
                       MR. HARRISON:  We will touch on that
           towards the end of the presentation as part of one of
           the questions.
                       DR. FORD:  Could I just make a comment,
           and it is more for education on my part.  When you are
           talking about initiating event frequencies, as I
           mentioned before, there is a lot of potential 
           material degradation issues.
                       And I say potential, because we haven't
           had them occurring so far.  But history unfortunately
           has told us that it can occur in the future.  Does
           that proactive future possibility, which can be
           analyzed, does that come into your methodology?
                       Do you understand what I am saying?  Such
           as the large cracking of large pipes was not
           anticipated before they occurred, and then they
           occurred, equally you can expect in the future that
           there is to be some occurrences of, let's say,
           vibration induced or flow induced vibration effects,
           and an effect on the CUF.
                       If you expect there to be increases in
           flux, and therefore on fluence, and that might have an
           effect, a predictable effect, how does that proactive
           thinking come into your decision making?
                       MR. RUBIN:  Well, clearly, there is not a
           one to one mapping into the risk models.  They don't
           have a scope like that.  As Donald said, we are
           relying on the condition monitoring programs, the in-
           service inspection programs, the augmented inspection
                       What I would reflect on though is that
           -- well, two items.  The mechanistically determined
           break frequencies on these plants through probablistic
           fracture mechanics are generally far below the assumed
           LOCA frequencies in the models.
                       If we started to see a large swing that
           would encroach on those differences, I think it would
           be probably picked up.  But it certainly is an area
           beyond the current modeling, and in a sense beyond the
           state of the art.
                       But I have not -- well, I will ask Donald
           to reflect on where the small LOCA contributions came
           in the risk profile of Duane Arnold.  I think it is
           probably pretty low.
                       MR. HARRISON:  Yes, there was -- there
           wasn't a driver in any of the change in risk that they
           reported as part of the power uprate.
                       MR. RUBIN:  How about the residual, the
                       MR. HARRISON:  I don't recall.  I would
           have to look that up.
                       MR. RUBIN:  Would expect it to be quite
           small.  There are other things driving the risk at the
           plant.  So it certainly is something that could
           conceivably occur, and hopefully through the programs
           in place to watch for performance in those areas, it
           would be caught and an appropriate response would be
                       But of course I am hypothesizing there,
           but I think the primary issue is that right now with
           the current plant profile that the LOCA frequencies as
           they are in the model aren't controlling risks, or
           aren't driving risks, or other things that are much
                       DR. FORD:  Just to take Gus' comment a bit
           further.  For instance, fatigue usage factors.  There
           will be presumably some flow induced vibrations, and
           that will affect the fatigue u sage factor, which will
           be even more exacerbated if you go to license renewal. 
           Now, has that thought process come into these
                       MR. RUBIN:  I think it certainly comes
           into the analysis from our colleagues in the division
           of engineering in assessing the uprate.
                       DR. FORD:  Okay.
                       MR. RUBIN:  And if they would care to
           comment on that.  Do we have anyone still here?
                       MR. WU:  Yes.  My name is John Wu from the
           chemical engineering branch.  I would like to comment
           on this.  The flow induced vibrations has been --I
           think the gentleman from G.E. mentioned that for this,
           20 percent power uprates, and the maximum rate does
           not change at all.
                       So for flow induced vibrations, we have
           been closely looking at this phenomena.  The maximum
           flow rate does not change and so we don't have that
           from the flow induced vibration concern.
                       And the only concern is probably that the
           flow goes through the main steam in the free water
           line, because of a 24 percent flow increase, and in
           this case, there are some vibration concerns because
           flow induced vibrations which is proportionate to the
           density of the root, also is proportionate to the
           square of the velocity.
                       But for this program, they have some kind
           of monitoring program, and so they will monitor this
           program very closely, such as inside the containment
           there are remotes, and some kind of monitoring device,
           vibration sensor.
                       And outside, they have people walking
           around and probably use hand-held monitors to monitor
           the vibration level.  And their criterion is that any
           vibration that occurs besides the audit, then they are
           to make sure that the vibration level, the insurance
           level, is below the endurance limit.
                       And the endurance limit is the limit that
           the material can vibrate and that there is no concern
           about the vibration.  And also I think Peter's
           comments about the collation between the power break
           and license renewal problems.
                       The license renewal, we have now the 10
           limit aging analysis, and it has been very closely
           reviewed by the chemical engineering branch.  So
           nobody is very small, especially for a big usage
           factor and it is below .5 and so it is very small for
           the intent of the component.  And for others, those
           are small, and normally we don't have a problem, you
                       DR. LEITCH:  I have another question in
           that area.  Even with core flow staying constant, the
           separator and dryer will see different flows or at
           least different quality steam as it comes up there. 
           Have you taken a look at the impact on the dryer and
                       MR. WU:  Those separators are -- I think
           this is probably alleged, but the point of view is
           that it is very, very small with the separator.  So we
           don't have a big usage problem.
                       Even the steam flow is higher than the
           power uprates.  But because there are separators out
           there, the insurance level is very, very small.
                       DR. LEITCH:  And how about the dryer?  Is
           it the same thing?
                       MR. WU:  The dryer is the same thing.  The
           dryer and the shroud top, they are together and the
           same thing, right, and is very small.  They combine
           with others, and it is very small.  So it is not a
                       DR. LEITCH:  Again, it is a question of
           quantification of very small.
                       MR. WU:  I do not recall the numbers of
           the quality usage factor, but they did calculate the
           usage factor based on the power uprates and especially
           for the dryer, and for this higher presentation of the
           power uprates.
                       CHAIRMAN WALLIS:  We can get numbers from
           G.E., I expect, this afternoon.
                       MR. WU:  Right.  It is very small.
                       DR. LEITCH:  Thank you.
                       CHAIRMAN WALLIS:  Again, I would like to
           know what very small is, too.
                       DR. FORD:  An initiating event, I assume
           that operational performance also comes into that
           particular category; is that true?
                       MR. HARRISON:  Actually, not as much as --
           you will have a separate look strictly at the operator
           response to initiating events.  But typically we are
           talking about the occurrence of a LOCA, or --
                       DR. FORD:  But the response time will be
                       MR. HARRISON:  The response time will be
           shortened, and that is on my next viewgraph, or the
           one after that.
                       CHAIRMAN WALLIS:  We have spent longer on
           the first bullet of the whole presentation than we
           were promised the whole presentation would take.
                       MR. HARRISON:  If we can proceed then.  On
           success criteria, Duane Arnold ran thermal-hydraulic
           evaluations, and the result of that rerun was to
           establish and confirm that their success criteria was
           still the same.
                       They did not identify any impacts on their
           success criteria as used in the PRA.
                       DR. KRESS:  These are things like how many
           ECCS pumps get started?
                       MR. HARRISON:  And how many pumps do you
           need, and how many RSVs do you need for
                       DR. KRESS:  Right.
                       MR. HARRISON:  Right.
                       DR. KRESS:  And things associated with
           containment, like the suppression pool, and --
                       MR. HARRISON:  The heat and the
           suppression pool.
                       CHAIRMAN WALLIS:  And temperatures.
                       MR. HARRISON:  Right.  They did  recognize
           plant parameters were changing, and that you will have
           more decay heat, and you will be producing more net
           than the model.
                       DR. KRESS:  Essentially when you ask the
           question about the PRA and how many pumps start and
           things like that, the same number would do the same,
           would prevent a core melt.
                       MR. HARRISON:  Right.  You still end up
           with the same success criteria, and you need -- there
           could be a change, and like in SRVs, you could go from
           needing 3 out of 6 to 4 out of 6.  They didn't find
                       I think that their deterministic analysis
           that they do on the DBAs actually did change that. 
           Their PRA though success criteria shows that 3 out of
           6 was still adequate for that.
                       DR. KRESS:  Is there some analysis that
           you guys had planned to do with something like the
           SPAR models that says that if I had a power uprate of
           this much, and X is an unknown quality, then my
           success criteria would change so that I have some pre-
           conceived notion of when to start really worrying
           about success criteria, that is really when you get an
           impact on CDF, is when you change those success
                       MR. HARRISON:  And actually that is an
           observation where at Duane Arnold that they held the
           success criteria, and where they would not give them
           the power uprate.
                       DR. KRESS:  But that was actually their
           condition on it?
                       MR. HARRISON:  That was their condition,
           and they saw that as a key point to hold.  We don't
           have that criteria necessarily, but if the success
           criteria did change, we would take a stronger look at
           that particular area to make sure what the effects
           were and what the change was in the CDF.
                       DR. KRESS:  It would be reflected in your
           CDF changes for sure.  Okay.
                       DR. LEITCH:  I noticed that the
           expectation is that in certain situations that the
           suppression pool temperature would be higher.
                       MR. HARRISON:  Higher, yes.
                       DR. LEITCH:  In some plants, I believe
           that suppression pool water is used to cool bearings
           and other support equipment for ECCS systems.  Did you
           take a look at whether that impacts the reliability of
           IPSY-RIXY or -- well, in other words, is that higher
           temperature water from the suppression pool adequate
           to provide appropriate cooling for IPSU and RIXY
                       MR. HARRISON:  I have not looked at that,
           and that is something that I could take back and look
                       DR. LEITCH:  And in fact I am not a
           hundred percent sure that at Duane Arnold that is the
           source of water for those bearings, but I think it may
                       MR. RUBIN:  I am not familiar with that
           cooling mode.  If they did employ anything like it,
           the suppression pool temperature limits should be
           constrained by the design basis requirements for
           cooling those systems.
                       And within that perimeter, I would expect
           no impact on reliability, and certainly you would
           exceed the qualified temperatures of components, and
           then you still have margin to failure off of it, but
           I think if you are still within the design basis, and
           they would have to be to get approval for the uprate.
                       I wouldn't expect to see an impact, but if
           we started to see it, it would be picked up by the
           performance monitoring or the performance indicator
                       DR. LEITCH:  But that supply to the
           bearings though, if it exists, is an subtlety that I
           just want to be sure has not escaped us in our
                       CHAIRMAN WALLIS:  Do seals get involved in
           this, too?
                       DR. LEITCH:  Yes.
                       MR. HARRISON:  Bearing seals, yes.  As was
           indicated, there are impacts to operator response
           times.  Again, they run the thermal-hydraulic codes to
           establish what those times are.  Typically what you
           see is impacts on the ATWS sequences in dealing with
           SLIC initiation, or inhibiting ADS.
                       As an example, for Duane Arnold that time
           changed from -- for early SLIC initiation, it changed
           from 6 minutes to 4 minutes, and the human error
           probability changed from about 10 to the minus 1 to
           about almost .2.
                       DR. KRESS:  They used 10 to the minus 1
           for their human error probability on that?
                       MR. HARRISON:  On that one.
                       DR. KRESS:  Good.  They didn't use 10 to
           the minus 3.
                       DR. LEITCH:  Right.
                       DR. KRESS:  And is this a plant that copes
           with ATWS by reducing the water level going into the
           core pretty far?
                       MR. HARRISON:  Yes.  I don't know how far,
           but they do lower water level to control power level.
                       CHAIRMAN WALLIS:  This 10 to the minus 1,
           is this just somebody's guess or is there some
           evidence on which it is based?
                       MR. HARRISON:  It is using a --
                       DR. KRESS:  Do they use the EPRI model?
                       MR. HARRISON:  I am getting a shake of the
           head.  Yes, they use an EPRI model for that.
                       CHAIRMAN WALLIS:  Because every time I see
           a round number like 10 to the minus 2, or to the minus
           1, I assume it is error, and that it is a factor or 2
           or 3 anyway.
                       MR. HARRISON:  But I am rounding off. 
           Their numbers were really 1.1 and 1.8, but --
                       CHAIRMAN WALLIS:  Oh, I see.  So they
           weren't just one-tenth of something.
                       MR. HARRISON:  Right.
                       DR. KRESS:  Which is false and misleading
           in terms of the --
                       MR. HARRISON:  Right.  When you are
           dealing with these limited times, you either make it
           or you don't make it.
                       CHAIRMAN WALLIS:  When they evaluate this
           do they actually talk to operators?
                       DR. KRESS:  Well, the models are based on
           operator simulation.
                       CHAIRMAN WALLIS:  Simulation responses?
                       DR. KRESS:  Yes.
                       CHAIRMAN WALLIS:  So it is real data then?
                       DR. KRESS:  It is a data based model, but
           it really has not been quantified very well, and they
           treat them as if there is no error in them.
                       DR. LEITCH:  I assume that Duane Arnold
           doe snot have automatic SLIC initiation, or are these
           numbers --
                       MR. HARRISON:  Right.  These are manual
           initiation of SLIC, and they have an early and they
           have a late.  So if they don't do it early, within the
           first four minutes of the power uprate, then they have
           until about 12 minutes, which is late for SLIC
                       As part of this, I indicated that it was
           driven by the operator actions of an increase in their
           CDF of about 10 to the minus 6, and an increase in
           their LERF value of 1.39 to the minus 7 per year.
                       DR. KRESS:  Just out of curiosity, what is
           the Duane Arnold CDF and LERF?
                       MR. HARRISON:  The CDF at Duane Arnold, 
           post-uprate, is 1.29, 10 to the minus 5 per year; and
           the post-uprate LERF is 9.9 to the minus 7 per year. 
           So you are getting about a 9 percent increase in CDF,
           and approximately a 16 percent increase in LERF.
                       CHAIRMAN WALLIS:  And most of that is due
           to ATWS is it?
                       MR. HARRISON:  Most of that is driven by
           ATWS.  There is some contribution from the transient
           non-ATWS, where you have high pressure failure and the
           operator fails to depressurize.
                       CHAIRMAN WALLIS:  What is the uncertainty
           in the prediction of this water level during the ATWS?
                       DR. KRESS:  It is pretty uncertain because
           it is tied into the actual calculation of what power
           you have got, and its relationship between power and
           water level.
                       CHAIRMAN WALLIS:  And maybe G.E. can
           respond to that this afternoon.
                       DR. KRESS:  Well, in fact, there has been
           a big argument over the years about how to make that
           calculation and what it actually ought to be.  So
           there is a lot of uncertainty there.
                       DR. LEITCH:  There is also uncertainty in
           how the water level is measured in those situations as
                       DR. KRESS:  Yes.
                       DR. LEITCH:  And whether where the water
           level is measured is indicative of what is really
           happening inside the core is another question.
                       MR. HARRISON:  The final bullet on this
           slide is just to recognize that they did look at
           external events, such as fires and earthquakes.  The
           same operator actions carry through into that
           analysis, but it has a minuscule contribution.
                       DR. KRESS:  Yes, I guess that is not
                       MR. HARRISON:  Right.
                       DR. KRESS:  Did they include any shutdown
           considerations in that?
                       MR. HARRISON:  We will get to that.
                       DR. KRESS:  Oh, okay.
                       CHAIRMAN WALLIS:  The next page.
                       DR. KRESS:  I'm sorry.  I didn't read
                       MR. HARRISON:  Okay.  The next category is
           component reliability, and again they don't expect any
           changes.  They maintain functionality reliability by
           monitoring programs, and they identify the few there,
           such as maintenance rule, erosion and corrosion
           program, condition monitoring, similar to the
           initiating events, such as the frequency discussion.
                       On shutdown risks, they did not do a
           shutdown risk model.  What they did talk about was the
           fact that they followed the guidance of New Mark
           91.06, where they control the five conditions.
                       They monitor to get heat removal
           capability, and inventory control, and availability of
           electrical power, containment control, and reactivity
                       And they just talk about maintaining those
           controls and being aware of the condition they are in
           before they remove equipment out of service.  The
           other point they did make was that at the increased
           power level and decay heat, you are going to take
           longer to shut down.  You are going to have to run
           your decay heat removal system longer.
                       DR. KRESS:  That was one of my questions
           was going to be; is are they going to use their same
           schedule for shutdown maintenance, or are they going
           to extend it out based on the new power limits?
                       MR. HARRISON:  The number of hours in
           order to get down.
                       DR. KRESS:  So if they wait long enough,
           then they are back to the same risk level essentially?
                       MR. HARRISON:  If you wait long enough for
           the decay heat to go away, then yes, and that just
           seems to be straightforward.
                       DR. CRONENBERG:  Under RAI ability, you
           accept that there is no change anticipated, or do you
           have additional information pending, or what is the
           status of your review on the component reliability?
                       MR. HARRISON:  In the are of component
           reliability, we have noticed this I think in the other
           reviews that we have done, that there really doesn't
           tend to be an impact in this area from these uprates,
           and so we have not pursued any additional questions in
           this area.
                       DR. CRONENBERG:  Including the balance of
           the plan?
                       MR. HARRISON:  And for Duane Arnold, that
           is correct.  For our other submittals, we are pursuing
           as part of initiating event frequencies and related
           component reliability of the uprates that they are
           doing to the balance of plant site, that could impact
           the PRA model.
                       MR. RUBIN:  This is an area where we
           really need to see some data if there is an impact,
           and we can't identify a mechanistic change, like a
           variation success criteria or fluid conditions.
                       It is really is not possible to predict it
           in a way to build it to the risk model.  However, if
           we do start to see changes, most of these items, or I
           think all of these items will be captured by 
           observations in other programs.
                       Plant trips will be caught by the firm's
           indicator program, and they will be monitored for the
           assessment program, and the reliability and
           availability of safety systems is monitored through
           the maintenance rule as was mentioned, as well as by
           the performance indicator program.
                       I certainly would be very interested to
           see the impact, and as was mentioned before, we should
           probably at some point in the future follow up to see
           if there is a change.  But it is not envisioned that
           there is right now,.
                       DR. CRONENBERG:  Your response relies on
           the monitoring program and after the fact as an
           indicator, when you know you have uprates of 17
           percent, and 15 percent, and 20 percent, you know that
           you are doing changes to your balanced plan before the
           systems and so forth.
                       It seems to me that I would have things on
           corrosion and erosion for plants that are 30 years
           old, and I would have some questions at to those.
                       MR. RUBIN:  I am sure there are questions
           in that area from the division of engineering.  It is
           not an area where the risk assessment would have it in
           the model.
                       DR. CRONENBERG:  Okay.  I am asking the
           wrong people then, I suppose?
                       MR. RUBIN:  In a sense, yes.
                       MR. HARRISON:  And keep in mind that the
           information that I am sharing is strictly a PRA
           perspective.  You are going to see it on another slide
           as to plant systems, and other groups will be tracking

           things that we don't track.
                       This is just a transition slide, and the
           next things that we are going to talk about is that we
           will quickly talk through PRA quality, and we will
           just give you a quick information dump on what we see
           as the risk impact that shuts down operations.
                       And then we will jump directly in to the
           six questions from the ACRS.  PRA quality seems to be
           a topic that is catching everyone's attention these
           days, and I do want to point out again that at least
           with the Duane Arnold submittal that they made it very
           clear that they were not a risk-informed licensing
                       The staff is reviewing the risk and
           pursuing that angle, but just to understand that the
           licensees don't necessarily see this as risk informed.
                       DR. KRESS:  Their PRA license
           certification process, that gives it some level of
           assurance that it is a pretty good PRA.
                       MR. RUBIN:  The certification isn't a
           pass/fail.  It is a --
                       DR. KRESS:  It gives you a classification
           and that these can be used for these things.
                       MR. RUBIN:  It gives you evaluations in
           various areas, and I am not sure which -- well, there
           is no overall assessment I guess is the way that I
           would like to leave it.
                       DR. KRESS:  Well, did you guys go to the
           certification review findings just to see what they
                       MR. HARRISON:  That is the last bullet on
           this page.  We are talking there about possibly
           sitting down and taking a look at the peer review that
           was performed.
                       DR. KRESS:  I'm sorry, but I didn't read
                       MR. HARRISON:  Shame on you for jumping
                       CHAIRMAN WALLIS:  I guess our view of
           quality in peer review is how much you can rely on the
           answers you are getting, and that is within a certain
           context.  So it is a measure of how uncertain are your
           answers compared with how certain you need to be in
           order to make a decision.
                       MR. RUBIN:  Right.
                       CHAIRMAN WALLIS:  I don't see that at this
           point in your discussion on PRA quality.
                       MR. HARRISON:  The point that I am making
           is that I am trying to make that point with the second
           one, is that the licensees are still meeting their
           deterministic requirements, and they are still 
           meeting the regs.
                       They are saying essentially, if I can put
           words in their mouth, that they are not relying on the
           PRA to make these decisions for that.
                       DR. KRESS:  So you are constrained to have
           to go by that, but you have one panel to get a hold
           of, and that is that there is a significant risk
           associated with that.
                       MR. HARRISON:  We have a way in.
                       DR. KRESS:  You have a way in, and so you
           need to see if there are significant risk changes.
                       MR. HARRISON:  Right.
                       DR. KRESS:  You need some sort of PRA.
                       MR. HARRISON:  And that is my third
           bullet, that the staff is assuring there is no
           significant risk change, and that there is no new
           vulnerability identified that we didn't know before.
                       We want to make sure that we are not on a
           cliff and a power uprate takes us from being in a safe
           condition to being in an unsafe condition.  So that is
           a perspective.
                       DR. UHRIG:  Does Duane Arnold have an on-
           line risk monitor like some plants do?
                       MR. HARRISON:  They have -- is it ORAM? 
           I don't think that is on-line, but that is a shutdown
           part of the model.  I don't think -- I really don't
                       DR. UHRIG:  That is just part of the PRA.
                       MR. RUBIN:  I guess we don't have the
           answer to that question.  We would have to check with
           the plant if they have a real time --
                       DR. UHRIG:  There are some plants that do
           have it and use it extensively.
                       MR. RUBIN:  There are also plants that
           have fast running models that they can requantify
           every morning in addition to the ones that have actual
           real time monitors, and I don't know where Duane
           Arnold falls.  Perhaps we could ask them if they know.
                       MR. BROWNING:  Again, this is Tony 
           Browning of Duane Arnold.  We are closer to the middle
           category.  We use the PRA to do our on-line
           maintenance planning surveillance testing, and we get
           a field there for where we are in risk space.
                       And then it is color-coded, and it is part
           of the plan every day when we go out and do
           maintenance so that we know exactly where we are at. 
           And emergent issues that come up can be factored back
           into the model and tell us do we need to make changes
           from what we planned.
                       But, no, we don't have the full-blown
           continuous on-line risk meter if you will.
                       DR. UHRIG:  This will be upgraded with the
           increase in power?
                       MR. BROWNING:  Yes, the models will be
           upgraded as we make the changes, and in particular
           like they said on their slide, we have a living PRA,
           and as the modifications are put into place those
           effects will be modeled.
                       DR. UHRIG:  Thank you.
                       MR. RUBIN:  If I could give an observation
           that when we were doing the baseline maintenance
           inspections, the plants that had the capability for a
           quick running quantification PRA model, it was
           certainly a significant strain in their ability to
           monitor the plant operations.  A number of plants
           essentially rerun the model every morning.
                       DR. FORD:  If I could make a comment.  The
           PRA, I recognize that there are limitations with the
           PRA methodology, especially when it comes to time
           dependent phenomena.  And when in the last couple of
           months, it has been drummed into us time and time
           again that the public perception of this whole
           business is very important obviously.
                       It just concerns me when you look at time
           limiting  and aging events, which we know historically
           occur, and the public knows that it occurs, that I am
           not hearing crisp answers to these particular issues
           when it comes to aging concerns, and when it comes to
           these particular out uprates.
                       I guess my question is more a comment, but
           my question is at what time do we hear crisp answers
           to these aging concerns?  Like, for instance, an
           informed person in the technical public could say that
           you should have a concern for fluence corrosion, or
           you should have a concern for flow induced vibration.
                       You should have a concern for irradiation
           effects on core shrouds, for instance.
           These are all reasonable topics, and they can all be
           put to rest.
                       MR. RUBIN:  Well, they certainly are. 
           They are in the areas of materials, chemical
           engineering.  We have a group that is involved in the
           review, I think, and perhaps we should get their views
                       DR. FORD:  I guess my question is when do
           we hear it.
                       MR. HOPKINS:  I guess I thought we had
           already made a presentation on erosion and corrosion
           previously to the subcommittee.
                       DR. FORD:  I apologize to the group then.
                       DR. KRESS:  He was not here during that,
           but you did make such a presentation.
                       MR. HOPKINS:  I think a better answer is
           the staff has to complete its review of Duane Arnold's
           submittal before we can really give that answer to
           you, per se, and we are still reviewing that.
                       DR. KRESS:  I think that your answer is
           that you are concerned with those things, and you have
           programs to look at them.  There are concerns for
           operating reactors that aren't being upgraded, but the
           question is does an uprated power do significant
           change to those.
                       And the answer that I am hearing is
           probably not, but we don't have good data to back that
           up on some of them.  Some things like chemical
           effects, we don't know if a power uprate is a
           significant effect.
                       We know how to deal with flow accelerated
           corrosion to some extent, and we know how to deal with
           fluences, but intergranular stress corrosion cracking,
           I don't know power uprate would do that.
                       So the answer is that I think that you are
           concerned with it, and you have programs looking at
           them, and the power uprate may not significantly
           change the concern.  You are still concerned, and I
           don't know what else you can say about it.
                       MR. HOPKINS:  Well, to some extent a power
           uprate is different from license renewal.  I mean,
           they each have the same concerns, but some are more
           concerned about power uprate than they are with
           license renewal, let's say.
                       So there are separate concerns, and in
           each case we look at those issues, be they time aging,
           or increase in fluence, or a small increase in
           fluence, and increase in flows, and that sort of thing
           for each review, to reach a satisfactory answer.
                       Duane Arnold is the first extended power
           uprate review, and we are not complete.  So I guess I
           am still back to when we complete the Duane Arnold
           review, that is when we are in a better position to
                       DR. FORD:  I guess it is a question of
           timing that I was bringing up, you know.  I don't
           doubt that these questions are being addressed that we
           brought up, but you are saying that this is going to
           be finished in the year -- well, later this year,
                       MR. HOPKINS:  Yes.
                       DR. FORD:  So when it comes to this
           committee, is it not a wee bit late for us to be
           saying suddenly, well, what about this, or what about
           that?  Doesn't that completely put a stone in the
           works as far as timing is concerned?
                       MR. HOPKINS:  Yes, it may.  But I don't
           see any way around it.  The staff has to do its review
           when we do our review.  The fact that the licensee may
           have requested a schedule and trying to meet it, and
           how much time we have to present to the ACRS, I think
           the ACRS should take its time to consider things that
           they can.
                       But we can't work faster than we are
           working.  So I'm sorry about that.
                       CHAIRMAN WALLIS:  I am not suggesting
           that.  I was wondering when you were asking for crisp
           answers if you were asking about the confidence in the
           expertise of the staff in evaluating things.
                       DR. FORD:  No, I am not questioning the
           competence of the staff.
                       MR. WU:  I will try to answer Peter's
           question.  This is John Wu again.  I think I mentioned
           before, sir, about life extensions in the power rates,
           and the corrosion between them.  Peter mentioned the
           corrosion and erosion, and also mentioned the flow
           induced vibrations.
                       In the life extension programs, the review
           includes, for example, the corrosion and erosion, and
           also review the aging management program, which is
           management controlled or managed by inspection, and
           also the chemical control.
                       And in flow induced vibrations, we look at
           the usage factor.  Say the usage factor now and then
           for 60 years, and see how much it is going to be, and
           what is the factor and we are including that in the
           review.  So that has been done.  The review has been
                       DR. CRONENBERG:  Why don't do you a
           cumulative usage factor for power uprates?
                       MR. WU:  We do have the cumulative
           factors.  You mean including the lab extension?
                       DR. CRONENBERG:  No, not for lab
                       MR. WU:  For the power uprates, yes.
                       DR. CRONENBERG:  As part of the review
           procedures for licensing, do you have to do a time
           aging analysis.
                       MR. WU:  If they have the power uprates,
           they also include in the reviews for the time limiting
           aging reviews, aging analysis.  They include it in the
           usage factor.
                       DR. CRONENBERG:  I looked at a number of
           reviews, like in the '90s when we did 4 or 5 percent
           type of increases, and I never saw a cumulative usage
           factor estimate in those reviews.  It is something new
           for these major, major increases.
                       DR. CRONENBERG:  Is this something that
           you knew that the licensee is required to do for the
           15 percent?
                       MR. WU:  Are you talking about the
           extension, the lab extension?
                       DR. CRONENBERG:  The time limitation on
           the CUF factors or estimates, cumulative usage factor
           estimates.  I never saw them before.
                       MR. HOPKINS:  I don't know.  We don't have
           Barry Elliott here anymore, and this may be more in
           his bailiwick.
                       DR. CRONENBERG:  They certainly weren't in
           the SERs that were talked about.
                       MR. WU:  I will find out about the lab
           extension on this cumulative factor, but for the power
           uprates, we have reviewed the cumulative usage factor.
                       DR. CRONENBERG:  And it is based on --
                       MR. WU:  On 40 years.
                       DR. CRONENBERG:  -- historical data and
           number of plants, and --
                       MR. WU:  Yes.
                       DR. CRONENBERG:  -- all those sorts of
                       MR. WU:  Yes.  Yes, that's right.
                       DR. CRONENBERG:  And that is impacted by
           the uprates?
                       MR. WU:  Yes, sir.
                       MR. HOPKINS:  Well, I think we got a
           little sidetracked, but I am back to the staff trying
           to review Duane Arnold and the staff is doing that as
           efficiently and as fast as we can.  And I think maybe
           to give you more specifics, we have to complete that
                       DR. KRESS:  Do you have a standard review
           plan for power uprates?
                       MR. HOPKINS:  No, we do not.  We
           considered that and at this time we have not felt it
           to be worth the effort, but no.
                       DR. KRESS:  But with all these predictions
           about what might come in for power uprates, are you
           thinking about reconsidering that?
                       MR. CARUSO:  Dr. Kress, BWRs have approved
           topical reports when you describe the uprate process.
                       DR. KRESS:  Well, actually we reviewed a
           couple of those.
                       MR. CARUSO:  Right, and those serve the
           same purpose as a standard review plan for BWR power
           uprate reviews.  They identify the key issues, and
           they identify what has to be looked at, and what has
           to be done by the licensee by the vendor, and by the
                       So to a certain extent, for the BWRs, yes,
           we do have -- we don't have an actual standard review
           plan, but we have a surrogate.
                       DR. KRESS:  This almost looks like a
           standard review plan.
                       MR. CARUSO:  That's why I say it is really
           the substitute surrogate.
                       DR. KRESS:  And you don't expect this
           magnitude of power uprate for PWRs do you?  Aren't
           there limitations there that keep them down a little
           lower maybe?
                       MR. HOPKINS:  Yes.  I think most PWR
           uprates will be on the order of five percent and it
           maybe if they replace steam generators, it might be 10
           or something.
                       DR. BOEHNERT:  Yes, some are coming in at
           10 or thinking about 10.
                       MR. HOPKINS:  But aren't those that have
           replacements involved?
                       DR. BOEHNERT:  I think so.
                       CHAIRMAN WALLIS:  We seem to be falling
                       MR. HARRISON:  Okay.  I will pick up the
           pace.  The last part is just to let you know that the
           staff is looking at the change in CDF and the change
           in LERF.
                       Most of these -- some of those we expect
           them to have peer reviews done on them at some level,
           and there is always the option for us to review either
           the peer review or the PRA itself.
                       MR. RUBIN:  Perhaps I should ask the
           committee if they want to go through each of the
           questions, or do you just want to select some that you
           want to hear?  We were planning to go through them, of
           course, but to save time --
                       DR. KRESS:  There are some interesting
           questions here.
                       CHAIRMAN WALLIS:  Well, I guess since we
           asked them, and you can answer if you like.
                       MR. HARRISON:  Okay.  I will run you
           through shutdown real quick, and then we will jump to
           the questions.  You are going to get increased decay
           heat and so that is going to extend the time the KE
           heat removal system is going to have to run, and
           remain in service.
                       As a result of the increased decay heat,
           you are going to have reduced upper response times.
           There is going to be a lower time to boiling.  The
           main effect is to PWRs that have a mid-loop operation,
           where the time is restricted to start with.
                       Those operations would be a higher risk
           than for BWRs that tend to have more inventory and
           more time to respond to things.
                       CHAIRMAN WALLIS:  Is this a significant
           change in the stored energy?
                       MR. HARRISON:  In the stored energy?
                       CHAIRMAN WALLIS:  Well, the fuel is
                       DR. KRESS:  It is almost a percent change,
           and not quite, but you can almost do it that way.
                       DR. SCHROCK:  What I heard them say is
           that the linear power is not changed.  They are just
           getting a higher power through flattening.  So if the
           linear power is unchanged, then the center line
           temperature is unchanged.
                       CHAIRMAN WALLIS:  But there is more stuff
           on the outside that is hotter than it was before.  So
           there is integrated decay and also integrated --
                       DR. SCHROCK:  The average temperature is
           higher than it was, right.
                       MR. HARRISON:  And I believe it is
           considered proportional to decay heat.
                       DR. KRESS:  The decay heat is
                       CHAIRMAN WALLIS:  And so all the effects
           are the same.
                       MR. HARRISON:  Right.
                       CHAIRMAN WALLIS:  Because it is a shorter
                       MR. HARRISON:  Right.  I will skip the
           next slide.  It just lists the six questions that the
           ACRS asked, and I will jump to the first question.
                       The first question basically was asking if
           we needed additional acceptance criteria to address
           the frequency of releases of all magnitudes, and just
           to state that Reg Guide 1.174 philosophy is that
           increases in CDF and risk are small and consistent
           with the Commission's safety code policy.
                       DR. KRESS:  Well, the intent of the
           question was to challenge the Reg Guide 1.174
                       MR. HARRISON:  I think we were aware of
                       MR. RUBIN:  Well, we certainly concurred
           with the advisory committee when they endorsed the
           criterion in the reg guide.  To look at it now for
           uprate, I don't think we see anything that calls the
           reasonableness of those criteria to question.
                       DR. KRESS:  Well, let me ask a couple of
           questions about that since this is one of my
           questions.  Let's talk about LERF.  Now, LERF was in
           the Reg Guide 1.174, and there is an acceptance
           criteria that is based on the actual absolute value of
                       You know, the closer that you get to the
           absolute value, the more regulatory attention one
           pays.  And that absolute value that they stuck in
           there was a surrogate for fatalities.
                       Now, if you uprate the power by, say, 20
           percent, and if you also have maybe three plants or
           two on a site, that is a 40 percent uprate on site
                       So to me that means that the consequences
           or the probability of -- well, they are not exactly
           linear, but the probability of fatalities has gone up
           to 40 percent at that site.
                       And it would make sense to me to reduce
           the acceptable LERF value to be a surrogate for that
           by 40 percent.  So I am questioning, number one, here
           you have a fixed LERF as the acceptance criteria, when
           in reality the LERF ought to depend on the power.  So
           that is question number one.
                       And question number two is LERF and CDF
           don't capture all your risk matrix, and it doesn't
           capture any suicidal risks, in the sense of total
           deaths or land contamination.  And it doesn't capture
           releases of fission products of all frequency, short
           of causing deaths.
                       And one of the studies in Europe showed --
           and I forget which plant it was for, but it showed
           that there was a significant increase in fission
           product release at lower frequencies, although it
           would not have affected LERF at all.
                       It was a significant concern to them, and
           so those were the nature of the questions that were in
           my mind when this was formulated, and it is actually
           challenging the 1.174 guidelines and criteria, and not
           that I don't think that they are relatively good, and
           I do support them.
                       But I am not sure that they are
           universally applicable under all conditions is my
                       MR. HARRISON:  I think we would agree that
           of course they are not universally applicable.  But
           within the bounds of the issues that were considered
           when the criteria were developed, I think they are
           still applicable for a power uprate of this kind, and
           I will be more specific.
                       When the 1.174 criteria were developed,
           whether with absolute criteria, or really guidelines
           rather than criteria, but absolute guidelines,
           percentage guidelines.
                       A lot of things were debated, and a number
           of members here were in on those debates.  And the
           ultimate decision was  to have guidelines that were
           site and plant independent.
                       And within the spectrum of the currently
           operating power plants, we have plants at 700
           megawatts, electric, and ones at almost 1,200.  And
           the risk between those two plants will be -- the
           differential will be larger than what we are talking
           about here for the uprated plant.
                       Does that mean that we are not considering
           the relative risks?  Well, there is a lot of margin in
           the safety goal between many of the plants with the
           frequencies of large release and core damage.
                       I think that you will find that a lot of
           the boilers have themselves on the lower end of the
           spectrum on overall core damage frequency.  Sometimes
           initial containment failure tends to be somewhat
                       But we still are seeing a lot more
           variability on just the range of currently operating
           plants than in the change that we would be applying
                       DR. KRESS:  That was another debate that
           we had.  The line that was drawn through the pump
           fatality scattered curve was the mean, and we wondered
           whether that might not be somewhat higher.  I mean,
           not to capture more of the plants.  But that was the
           -- it ended up being the mean.
                       MR. HARRISON:  But I think the underlying
           assumption is that regardless of where your plant is
           sited, and regardless of what your  base risk is, that
           the increases need to be small.
                       DR. KRESS:  And I think that is a good
           guideline, and the other that I was actually expecting
           you to say is that the rest of 1.174 says that you
           meet all the other regulations.
                       And since this was a non-risk informed
           submission, clearly it meets all the other
           regulations, because that is the philosophy behind
                       And that would control in my mind these
           lower frequency releases for this particular
           application.  But the question was more general; that
           if you actually had a risk informed application would
           you have problems along those lines somewhere.
                       MR. HARRISON:  I think if we started to
           see power uprates well beyond the upper range of
           currently operating plants, and well above 3,900
           megawatts, that might be the time to maybe take
           another look at the LERF guideline to see if it needed
           to be reassessed.
                       And in fact if you look at the upcoming
           revision to Reg Guide 1.174, you will see that concept
           reflected in that.
                       DR. KRESS:  That's right.  We are dealing
           with a revision aren't we?
                       MR. HARRISON:  Yes, sir.
                       DR. KRESS:  And I look forward to seeing
           that.  But anyway essentially 1.174 is all you have
           now, and so you are pretty much constrained to say
           that is what we would use.
                       MR. HARRISON:  And if you want, we can
           jump to the very last slide on the study that you --
                       DR. KRESS:  I think that was the one that
           I referred to.
                       MR. HARRISON:  It is the very, very last
           page of the package there.  They did a 15 percent
           power uprate and they stayed the same four areas as
           the NRC does in the area of PRA upper reactions, and
           success criteria, issuing event frequency, et cetera.
                       The one thing that the regulator did was 
           put a hold on success criteria and said that it will
           not change.  You will lower your power level if it
           does, and so that was one condition that they put on
                       DR. KRESS:  What do you think about that? 
           You don't have a position on that?
                       MR. RUBIN:  No, but if it was a
           significant change, it would be reflected in the risk
           analysis, and then we would be in a position at least
           to know what the impact did, and to make an educated
                       DR. KRESS:  Rather than just absolutely
           making --
                       MR. RUBIN:  It could be a trivial change,
           and it could be a significant change.  I think
           modeling it and looking at the impact makes more
                       CHAIRMAN WALLIS:  But that's if LERF stays
           the same, but the release goes up, and the overall
           risk does go up by something like -- well, more, and
           how do you assess that?
                       MR. HARRISON:  What this study gave was a
           frequency, a time, and it wasn't really a frequency. 
           It was a time period of a period content, and so the
           inventory goes up, and it gets released a little
                       So you have a shift, and so what they did
           find was none of the release categories changed.  So
           late stays late, and early stays early, and small
           stays small, and large stays large.
                       Everything just kind of shifts a little
           earlier, and you are getting a 15 percent increase in
           inventory.  So, yes, there is an absolute --
                       CHAIRMAN WALLIS:  So with the effect of
           public safety, what is the measure of small?  It's not
           that it goes up by 25 percent, but it goes up by
           something, and integrates overall frequencies and so
           on to get some measure of change in public risk, and
           how much does it go up?
                       MR. HARRISON:  This study did not take it
           to that level.  It did not take it to a dose
                       CHAIRMAN WALLIS:  Then how do they know it
           was small then?
                       MR. HARRISON:  We are talking about --
                       CHAIRMAN WALLIS:  The overall risk, and
           looking at all possibilities and all frequencies, and
           all releases, what is the net change by some measure? 
           They don't do that?
                       DR. KRESS:  There is no acceptance
           criteria that I know of.
                       CHAIRMAN WALLIS:  Well, there might be one
           in this one.
                       DR. KRESS:  Well, the Swedes have an
           actual acceptance criteria based on frequency of
           release of all risk, and there you have something to
           gauge to, but we don't have anything like that.
                       MR. HARRISON:  Right.  What they did show
           was that when you go through the level two analysis
           that the binning stays the same, and so your release
           categories don't change.  Your exit sequences don't
           change.  It is a matter of timing and just basic
                       CHAIRMAN WALLIS:  Well, when you have 
           release increases of 25 or 30 percent, what does that
           -- how does that affect your conclusion about overall
           risk?  There must be some mathematical way of going
           from 25 to 30 percent to something which you think is
                       DR. KRESS:  Well, it is not linear, and
           the consequences are -- well, this is related to
           consequences, and they have already said the frequency
           is not going to change very much.
                       So it is frequency times consequences, and
           the consequences of that kind of increase is not
           linear at all, but you could almost say that it is
           bounded by 25 or 30 percent.
                       CHAIRMAN WALLIS:  So it couldn't be bigger
           than 30 percent?
                       DR. KRESS:  It can be, but it is not much
           bigger.  It is all in your consequence model, and what
           iodine does to you, and things, but it is going to
           increase at least 30 percent and you can say that, but
           that is not much of an increase if you are already
           down to 10 to the minus 7.
                       And a 30 percent increase in 10 to the
           minus 7 is not --
                       CHAIRMAN WALLIS:  I would like to have
           that sort of rationale than just a statement that it
           is small.
                       MR. HARRISON:  And again I would say that
           the definition that they use for risk is increase of
           source term, and it is not necessarily a dose to
           somebody.  It is really just a stretch of the level
                       DR. KRESS:  Yes.
                       CHAIRMAN WALLIS:  Yes, but I think the
           answer should be crisp rather than discursive.  That
           there is some sort of rational mathematical model that
           gets you from the 30 percent or whatever you use as a
           button line --
                       DR. KRESS:  It is a delta-LERF is what it
                       CHAIRMAN WALLIS:  -- to say that he
           overall risk is small.
                       DR. KRESS:  Well, they  use delta-LERF and
           that's it.
                       CHAIRMAN WALLIS:  And it is not affected
           at all by the release.
                       DR. KRESS:  It's probably not, that's
                       MR. RUBIN:  That is the point of the
           question, Dr. Kress.
                       DR. KRESS:  And that is basically the
           point of my question.
                       MR. RUBIN:  In a sense, it is a limitation
           of the method, but it also reflects the reality that
           the source term is just the same as a source term for
           a similar power plant next door that was running at 70
           megawatts higher of power.
                       DR. KRESS:  But I don't like that
           question, because a source term is fraction of
           inventory, and that is not a good answer I don't
                       MR. HARRISON:  And the overall result of
           that study was basically the conclusion that they were
           -- that this risk increase is still within the
           uncertainty band of the phenomenology.
                       DR. KRESS:  That's for sure.
                       MR. HARRISON:  So we are going to have to
           have a much larger increase impact than that to even
           get outside of the --
                       CHAIRMAN WALLIS:  So what you are saying
           then is that you apply the rule that everything is now
           fine, and you are a little bit uncertain about how you
           take care of this thing, which is not really accounted
           for by the rule, but you are not really too worried
           because the effect is not really big as far risk is
                       DR. KRESS:  And they still meet all the
           figures of merit in Chapter 15, which is a level of
           comfort to some extent with respect to this.
                       CHAIRMAN WALLIS:  So question two.
                       MR. HARRISON:  We will go back to question
           two.  Question Number 2 dealt with margins.
                       DR. KRESS:  I think you basically answered
           my question on that one, and that is the bottom line,
           that you can use margins all the way up to the limit.
                       MR. CARUSO:  One of the questions that you
           raised during the earlier session was about fuel
           center line temperature.  We talked a little about
           that at the break and these power uprates are not
           raising fuel center line temperatures.
                       What they are doing is they are flattening
           power profiles throughout the core so that you don't
           -- so that the limiting bundle is still operating
           where it was before.
                       But what you are having is that you are
           having other bundles which were previously well below
           that operating much closer to that limiting value.
                       And the other question you raised about
           operating.  Even if you were operating with a higher
           center line temperature, fuel melting is not allowed. 
           There are design criteria that prevent that, and we
           were also thinking about the fact that even if you
           were operating with higher fuel temperatures, realize
           that through its life that the fuel doesn't maintain
           its monolithic character.  It fragments quite a bit.
                       So it is not clear to us how much
           additional release of fission products you would have
           from the fuel because you are operating a little bit
           hotter, because I would have to go back and see how
           much additional fragmentation would occur.
                       And I am not sure that the increase in 
           that temperature really would increase the fission
           product release into the gap by that much other than
           the linear race due to the fact that you are burning
           up faster, and so you would have a higher inventory.
                       And other than that, I am not sure that
           the power uprates are really changing gap activities.
                       DR. KRESS:  The gap activity is probably
           not risk significant anyway.  I mean, it has to do
           with operational things, and how fast you close
           isolation valves and stuff like that.
                       But it is probably not a risk significant
           thing, unless you are talking about PWRs, and if the
           gap inventory actually has some effect on the iodine
           spike, and you have a steam generator to rupture,
           which is all speculation on my part that it would. But
           I can't see any problem with BWRs frankly.
                       MR. HARRISON:  And we will hit that
           portion, and I think that is question number four on
           the gap fraction of the iodine spiking.
                       DR. KRESS:  The other thing about the
           margins that occurred to me when we asked this
           question was you have margins now for these figures of
           2,200 degrees, and that are met generally well below
           the value, and it has been deemed an acceptable margin
           because you have some idea that the calculations to
           get those involved build in conservatisms.
                       And as you approach that margin more and
           more, I think that your level of comfort about what
           those built-in conservatisms do for you, since they 
           have never really be quantified about how much
           conservatism there is added into the calculation, that
           your level of comfort about having conservatisms in
           your calculations is eroded somewhat.
                       And to me it says that when we get closer
           and closer to those margins, maybe we ought not to
           rely on Appendix K, and ought to go to the best
           estimate approach.  And actually quantify the
                       MR. CARUSO:  That is what is happening.
                       DR. KRESS:  And once you quantify the
           uncertainties, then I see a missing element, and that
           is how to factor that in to how close you can get to
           these many figures of merit.
                       I don't see that missing link, you know. 
           I have got the conservatisms, and I have got a
           calculation of the mean or the distribution and how
           close it is to the margin.  So now what is acceptable
           to me.
                       CHAIRMAN WALLIS:  Well, you are getting at
           the bottom line here.  I think what the bottom line
           says is that they control up to the -- well, it is not
           really limits on margins.  The limits are on things
           like temperature, like 2,100 degrees.
                       But there is nothing that says that you
           have got to have a margin of so much, which is in some
           approved way.
                       MR. CARUSO:  Margin was used to establish
           the limit.
                       CHAIRMAN WALLIS:  Margin simply means that
           the prediction is below the limit, that's all.
                       MR. CARUSO:  The prediction is below the
                       CHAIRMAN WALLIS:  And there is no
           quantification of margin whatsoever in the
                       MR. CARUSO:  It depends on what it is that
           you are calculating.  As I said, we are seeing more
           and more people trying to do statistical
                       The SAFER/GESTR method actually is a very
           early attempt to do that, and if you look at the
           SAFER/GESTR methodology, you will find that they meet
           the 2,200 degree limit, but the staff has imposed
           actually I believe a 1,600 degree limit on SAFER/GESTR
           on a separate non-licensing calculation as part of
           SAFER/GESTR, which is called the upper bound PCT,
           which includes a certain uncertainty factor.
                       So it is a way of -- I don't want to get
           into the details of explaining this, but they have two
           limits; one which is much lower, and which is where
           they actually believe the plant operates.
                       But then they take a penalty because of
           difficulties in quantifying the uncertainty to make
           sure that they stay below 2,200.
                       CHAIRMAN WALLIS:  So does anything change
           with uprates then?  This is what you have been
           accepting.  Is there anything different about uprates? 
           Are their margins significantly reduced or anything?
                       MR. HARRISON:  They are coming closer to
           these limits.
                       CHAIRMAN WALLIS:  But not by much.  Are we
           going to hear that from G.E.?
                       MR. HARRISON:  I think so.
                       CHAIRMAN WALLIS:  From my reading of it,
           it didn't look like much of a change, but I am not the
           regulator.  You are much more experienced than me
           about whether it is significant or not.
                       MR. HARRISON:  Well, one of the things
           that -- well, remember what I said when I started just
           now was the peak limiting bundles on changing, and
           what they are doing is flattening the power shape
           throughout the core.
                       And so there are lots of areas in the core
           right now that aren't carrying their loads so to
                       CHAIRMAN WALLIS:  I guess the think that
           -- the question really to ask is not what the
           licensees and vendors are doing, but what you will
           decide to accept as a margin.  What is your criterion
           for accepting a margin, and not what the licensees and
           vendors are controlling.
                       MR. HARRISON:  Well, we have one li mit in
           Appendix K, and the other limits come from reviews of
           the topical reports.  We had some old limits that were
           very deterministic, and very conservative, and now we
           depend on the vendors and the licensees to come to us
           with proposals and we talk to them.
                       CHAIRMAN WALLIS:  And you negotiate?
                       MR. HARRISON:  And we negotiate.
                       CHAIRMAN WALLIS:  And you use your
                       MR. HARRISON:  That's right.
                       CHAIRMAN WALLIS:  But you don't have a
           sort of spelled out --
                       MR. HARRISON:  And we call on our friends
           in the Office of Research to help us, and we call on
           our friends in the ACRS to help us.
                       CHAIRMAN WALLIS:  But you have not got
           spelled out criterion for margin approval?
                       MR. HARRISON:  You would have to look at
           the details of each individual topical report.
                       DR. SCHROCK:  Is it true that the limiting
           bundle power isn't changed?  That implies that all the
           flattening is radial and none axial.
                       MR. HARRISON:  I think there is also
           flattening in the axial direction.
                       DR. SCHROCK:  Then there would need to be
           a higher bundle power.
                       CHAIRMAN WALLIS:  We will get that from
           G.E., I guess.
                       MR. HARRISON:  I am hearing only radial.
                       CHAIRMAN WALLIS:  Well, it's not too
           obvious from this material here.  I mean, if that is
           what they are doing, then it needs to be said up
           front, because then you stop asking all the questions. 
           We probably need to move on.  We are not making much
           progress with margins.
                       DR. SCHROCK:  Marginal progress.
                       MR. HARRISON:  Question Number 3 was a
           question relating to the need to reflect the increase
                       CHAIRMAN WALLIS:  There isn't any
           increased burnup is there?
                       DR. KRESS:  There is an increase in the
           average burnup, but they are still within the limits.
                       MR. HARRISON:  And also if you changed
           your operating cycle or whatever, and to extend the
           cycle, then that would have an effect on your burnup
           as well.  But it is indirect, and not a direct effect
           of the power uprate.
                       The use of the thermal-hydraulic codes
           that are used to establish the success criteria and
           the operator timing, the staff feels that should be
           reflected what your core is.  That is part of PRA
           quality; do you reflect your current design or your
           projected design in operating conditions.
                       However, I will point out, and as I think
           you are all aware, that the delta-LERF will probably
           not reflect the increase in inventory and that is the
           prior question.
                       DR. KRESS:  That is the same thing you
           said before.  I was wondering if -- well, it does give
           a potentially bigger insult to the containment.
                       MR. HARRISON:  Right.
                       DR. KRESS:  And that is calculated.
                       MR. HARRISON:  That would be calculated.
           That would be passed through from --
                       DR. KRESS:  So, delta-LERF would reflect
                       MR. HARRISON:  Right.  And actually on
           Duane Arnold, even though the CDF went up by 9
           percent, the LERF went up by 16 percent, and it had to
           do with the predominance of it being ATWS events.  So
           that pushed you -- you had a disproportional amount of
           the scenarios being pushed earlier.
                       DR. KRESS:  And ATWS is the dominant
           sequence for doing Arnold isn't it?
                       MR. HARRISON:  Yes, it is.
                       CHAIRMAN WALLIS:  I am sort of assuming
           that you are going to be finished by 11:30, and then
           we can have Jack Rosenthal so that we can get to lunch
           before noon?
                       DR. KRESS:  It all depends on us.
                       MR. HARRISON:  We only have two more
           questions really.  So we if can walk through them
           quick.  And question four had to do with the impact on
           the design basis analysis source term.
                       As we said before the fission product
           inventory will increase.  There was a question on gap
           fraction, and it is considered -- well, the power
           uprate has no direct impact on the gap fraction.  It
           is a function of the burnup of the fuel.
                       DR. KRESS:  And it doesn't have any effect
           on the gap fraction, but it does have an effect on the
           total amount.
                       MR. HARRISON:  On the inventory.  And on
           the second part of that dealing with the iodine, I
           think it was mentioned earlier that the appearance
           rate and spiking factor are based on the tech spec
           equilibrium activity, and I believe the staff 
           believes that the 500 times multiplier that is used
           compensates for any uncertainty that is in the iodine
                       DR. KRESS:  Well, that is one of the
           things.  This was Dr. Powers' question, that part of
           it anyway, and that is one of the things that he will
           stand up and make a few statements about.
                       We had a lot of discussion about this 500
           with respect to the differing professional opinion,
           and we weren't very pleased with it.  But that is all
           you can have is what is in the books, and it is not a
           question related to Duane Arnold.  It is something for
           the future.
                       MR. HARRISON:  I think there is a plan to
           reevaluate the iodine spiking.
                       DR. KRESS:  Yes.
                       MR. HARRISON:  The last two slides. 
           Operator time required.  I think we have made it clear
           before that this is the one area that really does get
           impacted by a power uprate.  You end up with shorter
           response times that are available, and that results in
           a larger error probability for the operators.
                       DR. KRESS:  And when I heard  you
           generally using .1 for the error probability, that
           gave me a lot of comfort with respect to this
                       MR. HARRISON:  Okay.
                       CHAIRMAN WALLIS:  You get confident when
           the probability of error is 10 percent?
                       MR. HARRISON:  No, it gives him confidence
           that the results aren't artificially low.
                       DR. KRESS:  That's right.
                       CHAIRMAN WALLIS:  I would hate to be an
           airplane with that sort of human error probability.
                       MR. HARRISON:  Again, that particular
           scenario was the early initiation of SLIC.  I think
           you only had under the uprate, there is only four
           minutes, and that's why you get --
                       DR. KRESS:  It was originally six.
                       MR. HARRISON:  It was originally six and
           so you didn't gain that much.  You didn't lose that
           much, but you still have that.  Are there any
           questions on operator actions?
                       CHAIRMAN WALLIS:  Well, to solve this
           problem could it be reduced by better training?
                       MR. HARRISON:  In the modeling?
                       CHAIRMAN WALLIS:  No, in reality.
                       MR. RUBIN:  They are trained.  They are
           trained well, but it is a very short period of time,
           and to diagnose an ATWS is, I guess, somewhat complex
           in a cognitive sense, and that's reflected in the
                       CHAIRMAN WALLIS:  So you are reaching the
           limit of human capabilities here, and it is not a
           question of better training?
                       DR. KRESS:  You are getting close.  You
           have four minutes to decide if you have an ATWS, and
           go to the emergency guidelines and do what it says to
           do for an ATWS.  That is getting pretty close.
                       DR. LEITCH:  They are trained on it on
           almost every training cycle.
                       DR. KRESS:  It is training as soon as you
                       DR. LEITCH:  I think the problem is as was
           indicated, that it is relatively short time, and also
           somewhat counterintuitive, in spite of your training.
                       DR. KRESS:  It is one of those places
           where instead of saying get water on the core, it is
           going ahead and lower the water level.
                       MR. CARUSO:  Well, I guess it is figuring
           out if you have an ATWS or something else going on,
           and diagnosing what is happening.
                       DR. KRESS:  That is part of it, but I
           think that ATWS gets to be pretty clear very fast.
                       CHAIRMAN WALLIS:  You would say a minute
           maybe that you know that you have got an ATWS?
                       DR. KRESS:  Less than that.
                       MR. RUBIN:  The first thing they do is
           check the bottom lights.
                       DR. KRESS:  That is a pretty good
                       MR. HARRISON:  And given that you do know
           that you have shorter time, there is actually almost
           an argument that it has got your attention.  For
           example, in shutdown operations, if you are in mid-
           loop shutdown operations, you know you have only got
           a few minutes to do things and you are going to watch
           it a little closer.
                       So you can almost have an improvement on
           operator performance in some situations.
                       DR. LEITCH:  In some plants, ATWS is
           automatically initiated, where there is a SCRAM
           signal, and if the power is not down in five seconds,
           in goes SLIC.
                       MR. HARRISON:  I just put up this last
           slide on question 6A, which was the need to assess
           operational data.  Again, licensees currently track
           and trend their operational data, and they have the
           maintenance rule, and they have a corrective action
           program, and they have condition monitoring programs.
                       The staff believes that any significant
           impact resulting from a power uprate would be self-
           revealing.  If Duane Arnold starts getting 3 or 4
           trips a year, it is going to catch someone's
                       If all of a sudden pumps start becoming
           unreliable, it is going to get somebody's attention. 
           And the staff is --
                       DR. KRESS:  How many trips per year is in
           the performance indicator now?
                       MR. RUBIN:  I didn't bring the little
           chart with me, but to get red, you need 20.
                       DR. KRESS:  And to go out of the green,
           you need three?
                       MR. RUBIN:  Yes, three.  I think it is
                       MR. HARRISON:  But the point is that the
           staff is trying to figure out a way to use the
           performance indicators and the monitoring programs to
           look back and see are there any impacts.  We don't
           expect there are, and the PRA says there is not, but
           we still need some kind of confirmation to look back.
                       So we are talking and discussing on how we
           can use that to get an early indication that maybe
           there is an impact that we hadn't expected to see.
                       DR. KRESS:  That is a great idea, I think.
                       DR. LEITCH:  I think the -- if I am not
           mistaken, I think the present criteria is a three year
           rolling average, too.  So you may early on in the
           process want to take a look and see whether there is
           something more immediate happening.
                       Sometimes a three year rolling average can
           sort of disguise something that is going on.
                       MR. HARRISON:  And we do have the -- I
           believe in looking at the cute little charts that you
           can actually get where they are at that point.  So you
           can break down the data to see that Duane Arnold is
           going from 1-to-2-1/2, or 1 to 2.
                       It is really not the initiating events
           that would be -- those I really do believe would be
           self-revealing.  The harder ones would be component
           reliability, where you may be taking a pump down for
           maintenance more than you were before, and that is a
           harder one to get the information to track.
                       MR. RUBIN:  But they do have the
           maintenance rule on availability criteria, the A1A2
           demarcation, and maintenance unavailability will be
           flagged directly if they exceed their goal.
                       CHAIRMAN WALLIS:  Are we at the end of y
           our presentation?
                       MR. HARRISON:  I am at the end.
                       CHAIRMAN WALLIS:  I would ask Mr. Hopkins
           if we can have a summing up from you, and would you
           prefer to do it now before we hear from RES or do we
           need to hear from RES before we hear from you again?
                       MR. HOPKINS:  I could do it now and it is
           very short.  I understand the questions and mainly
           from our perspective in reviewing Duane Arnold, and
           that is the first extended power uprate, that we are
           trying to work the Duane Arnold schedule of completing
           it by October, which would be a full committee
           briefing in September.
                       And so we are trying to have as much
           communication with ACRS to get this done as we can,
           and I understand some of the concerns and questions
           here today.
                       CHAIRMAN WALLIS:  Well, it's not really
           where the ACRS is on this.  It seems to me that you
           are still reviewing and some of these questions have
           not been resolved, and until we see something more
           definite, I am not sure that we want to write a
           letter, because your opinion may change.
                       And we don't want to write something on
           this that is not based on something that is -- well,
           that is based on something that is too uncertain at
           this point.
                       MR. HOPKINS:  Right, and I wasn't trying
           to insinuate that.
                       CHAIRMAN WALLIS:  And so you don't want a
           letter from us.  I think it would be inappropriate for
           us to write a letter now until perhaps you have
           reached some firm conclusions on these points.  Is
           that a correct assessment?
                       MR. HOPKINS:  I agree with that
           assessment, yes.
                       CHAIRMAN WALLIS:  And so you are going to
           appear before the full committee?
                       MR. HOPKINS:  Yes.
                       CHAIRMAN WALLIS:  Is that what we plan to
           do?  And do you somehow have to shorten this
           presentation to something that the rest of the
           committee needs to know?
                       DR. BOEHNERT:  We can discuss what we want
           to do as far as having them come before the committee
           next month.  There are some issues that --
                       CHAIRMAN WALLIS:  You do need to focus on
           some other issues that we need to worry about.  That
           is the important thing.  Otherwise, it is really a
           question of whether you are on track with your review,
           and that is more of a management issue for you folks
           than it is for us.  We may have an opinion, but it is
           not really our job to plan your activities.
                       MR. HOPKINS:  Yes.
                       CHAIRMAN WALLIS:  We may catch you in the
           hallway and say something about that and say whatever.
                       MR. HOPKINS:  I understand that it is a
           management decision, and new priorities are looked at
           continuously.  All I can say is that the Duane Arnold
           power uprate is a high priority.
                       CHAIRMAN WALLIS:  I think we need to be
           somehow assured that the bases are properly covered
           and that things are done by October and something is
           not overlooked, and that is the sort of thing that we
           worry about.
                       MR. HOPKINS:  I appreciate that.
                       CHAIRMAN WALLIS:  Is there anything else
           from the other members of the committee at this point? 
           Can we move ahead then.  Is this Jack Rosenthal?
                       MR. HOPKINS:  Yes.
                       CHAIRMAN WALLIS:  Thank you very much.
                       MR. ROSENTHAL:  My name is Jack Rosenthal,
           and I am the newly appointed branch chief of the
           safety margins and systems analysis branch.  Farouk L.
           Quila (phonetic) is my division director.
                       DR. KRESS:  Is that a new branch?  I have
           never heard of that branch?
                       MR. ROSENTHAL:  No, it is Farouk's branch. 
           Farouk was promoted to be the division director.
                       DR. KRESS:  I knew that and we need to
           congratulate him I guess.  Did you change the branch
           name or --
                       MR. ROSENTHAL:  No, no, the branch has
           always been the same, but it was Farouk's branch. 
           This is a reorganization from a year ago March, and
           about every two years we reorganize.  So Farouk became
           the acting division director, and I became the acting
           branch chief for a while.
                       DR. KRESS:  And how it is no longer
                       MR. ROSENTHAL:  Right.  And I am not
           pretending either.  And although I am speaking from a
           branch perspective, I did coordinate what I have to
           say with the risk assessment people, and also with the
           division of engineering.
                       And we do fuels, thermal-hydraulics, and
           severe accidents, and consequence analysis.  And I
           don't mean this to be -- I won't dwell on the point,
           and I don't want to be overly scholastic, but we see
           lots of system interactions that we can think of, and
           I have yet to come up with what I consider synergy.
                       And let me explain what I meant.  I went
           to my fuels expert, and he says, gee, if you run the
           fuel a little bit harder, or a little bit hotter
           temperature, don't you release more fission and gas,
           and he said, yes, we have known that for 35 years, and
           it is a sensitive function of the temperature.
                       And if you go to higher burnup, core
           average burnup, because you still want the same
           overall fuel cycle, don't you end up with a bigger
           fission -- and he said, yes, we know that also.
                       And I said, well, is there a situation
           where 3 percent and 3 percent ends up as 9 percent
           rather than 6 percent, and the answer was no.  So that
           we sort of know these effects.
                       And so I have yet to come up with what I
           consider a synergy.  And distinct from that, we know
           of lots of interactions.  I mean, we clearly know that
           the fluents goes up and the effect on the vessel,
           which is small for a boiler --
                       DR. KRESS:  Was this Ralph Myer that you
           were talking to?
                       MR. ROSENTHAL:  Yes, sir, who is part of
           the branch.  Some of the phenomenological interactions
           are things like the effect on the core instabilities
           that would be the result of -- well, as it turns out,
           if you have an ATWS, you trip the recirc pumps.
                       And once you trip the recert pumps,
           automatically you fall into the unstable breaches as
           it turns out, but what that would mean in terms of
           fuel performance is an outstanding question.
                       DR. CRONENBERG:  Let me give you a synergy
           there, Jack.  Flow assisted corrosion.  Corrosion by
           itself will take a certain amount of time.
                       MR. ROSENTHAL:  Right.
                       DR. CRONENBERG:  And flow by itself would
           rip away material from a piping wall.
                       MR. ROSENTHAL:  Right.
                       MR. CARUSO:  But corrosive products with
           added flow could be a compounding effect.  So you
           asked Ralph for a quick answer, and maybe you should
           have asked some materials people, and you might have
           gotten a different answer.
                       MR. ROSENTHAL:  Fair enough.
                       DR. KRESS:  And I think that Ralph is
           basically correct on those things that you said.
                       MR. ROSENTHAL:  Okay.  It is also somewhat
           of a management challenge for us, which we will
           address, to face up to some of these issues, because
           they are truly interdisciplinary, and I will give you
           an example.
                       Yesterday, I was talking with a true
           expert in thermal-hydraulics, and I said, you know, if
           you push harder on the generator and you have not
           changed the generator, you will get more power and
           fewer BWRs, and he said what is a BWR.
                       So I raised my right hand and I said a BWR
           is -- and he said, oh, I remember.  Okay.  And the
           point is that what we need to do in this search for
           interaction synergies is to go across disciplines, and
           I will get back to that specific example in a moment.
                       And what I am trying to do is describe in
           fact researcher's plans, and that we are not currently
           doing a project, although I do owe my boss a formal
           memorandum of plan with tasks, and I owe that this
                       We intend to be quantitative in our
           assessment, and we have the ability to run codes like
           TRAC and we have coupled three, or it is now a module
           of TRAC, and so we can do 3-D based on kinetics.
                       And we intend to use that capability for
           things like ATWS, and it is because we believe that
           when we do the analysis that we learn a lot by doing
           some quantitative work.
                       CHAIRMAN WALLIS:  So when will you do
                       MR. ROSENTHAL:  In Fiscal 2002 and 2003.
                       CHAIRMAN WALLIS:  But they want an answer
           by November of this year.
                       MR. ROSENTHAL:  This is a generic, and not
           a --
                       CHAIRMAN WALLIS:  So it is a long term
           anticipatory research?
                       MR. ROSENTHAL:  Yes, sir.  We will start
           with boiling water reactors.  I think if there are
           some questions on PWRs and again involving ATWS, where
           there is the potential for more positive MPCs that we
           would like to look at.
                       But to the extent that we are dealing with
           real boiling water reactors, we are asking for
           extended power uprates, and that is where we should
           look first.  But we will do some PWR work later on.
                       We are going to not focus on the Chapter
           15 analysis.  The licensee, the vendor, and NRR are
           pressing those issues; but rather to at least have our
           focus being on success criteria in --
                       DR. KRESS:  I think that is really a good
           choice for you guys, because I think you can rely
           mostly on this staff's review of the licensees for the
           design basis stuff, and this is added value here.
                       MR. ROSENTHAL:  Thank you.  And we also
           would like to look at some of the generic issues and
           severe accident issues that would be part of -- or may
           not be part of and addressed otherwise.  As I said,
           this is a two year effort.
                       Farouk did speak before this committee
           several months ago, and we have been through a budget
           cycle, and it is now as we see it a currently budgeted
           activity.  We do intend to do the work, and distribute
           it at least amongst three branches.
                       So how will I -- well, this is a search
           for issues, and there may not be any.  I do not have
           a smoking gun, and if I did, it would be my obligation
           to notify NRR.
                       So if we could look at this list, and we
           will look at blackout and loss of heat removal, and I
           think we will look at loss of coolant, because it is
           of interest to us, even though we recognize that in
           most PRAs that loss of coolant actions are not
                       We want to also -- and I will say review,
           less significant accident sequences, and ask ourselves
           the question could these sequences -- because the
           success criteria may change -- become more important.
                       And the example that I could use, and it
           is only as an example in my thought process, is large
           break LOCA and boiling water reactor is clearly not a
           risk dominance sequence.
                       If we were to somehow conclude that with
           the flatter power distributions, core spray now is
           very important, and the core spray distribution is
           very important, and if there is a problem with it,
           then --
                       DR. KRESS:  How would you look at that? 
           Would you just go in with your code and arbitrarily
           say or do some power metric studies on the
           distribution and see what it does to success?
                       MR. ROSENTHAL:  It is a capability that we
           have developed with TRAC, and put in a flat power
           distribution which we think is representative of what
           is going on.  We won't know anything more about core
           spray distribution.
                       DR. KRESS:  No, but you could arbitrarily
           vary that.
                       MR. ROSENTHAL:  Yes, sir.
                       DR. KRESS:  And the bypass amount that you
           get is okay.
                       MR. ROSENTHAL:  And see if it affects the
           results.  And it is conceivable, although I don't
           expect, that there is some problems with the success
                       If it were, then it would make something
           that is not risk dominant, and make it very important. 
           That is the type of search we would like to do.
                       DR. KRESS:  I think where your problems
           are going to be are in the carryover term, and I don't
           know how you deal with that.  When you increase and
           flatten out the profile, I don't know what that does
           to carryover.  But that is the only place I see where
           that could make a lot of difference.
                       MR. ROSENTHAL:  Yes.  But we think we
           ought to be looking at those, and not just -- well, at
           least do some looking, and we will do definitely some
           quantitative analysis, and we will do some reviewing
           of the less sequence and think our way through it.
                       I think we want to also review some of the
           prior generic issues.  We put in this power/flow
           stability issue in that category, but there were other
           things that the agency faced and resolved in the past,
           like the hydro-dynamic loads on the Torus, which would
           be different now.
                       And we would intend to go back and look,
           and in fact what I intend to do is go down the list of
           generic issues that we have resolved and think our way
           through which things might be different at the higher
                       CHAIRMAN WALLIS:  Do you know you have the
           -- coupled with the neutrionics code, does it predict
           flow stabilities?  Do we know that yet?
                       DR. KRESS:  I don't think it does.
                       MR. ROSENTHAL:  I don't know.
                       DR. KRESS:  I don't think it does.
                       MR. ROSENTHAL:  As I said, what I have
           brand new is this 3-D spaced on kinetics capability
           that we now have.
                       DR. SCHROCK:  What is the name of that?
                       MR. ROSENTHAL:  Well, it is a module, and
           we have made it into a module of TRAC and its parts,
           and that is from Purdue.
                       CHAIRMAN WALLIS:  So one success that you
           could establish would be that you could model power
           flow stabilities with these codes, that would be a
           success if it hasn't been done before.  I don't know.
                       DR. KRESS:  Well, they have models.
                       CHAIRMAN WALLIS:  And if you have a model
           and the codes can't do it, that's not so good.  It
           would be better if the code did it by itself.
                       MR. ROSENTHAL:  Well, then you have to
           know whether you trust what you have got.  But in that
           case, it is an area that we would like to explore and
           we think it is appropriate to explore this area.
                       I have a related area, and that is that
           again it is ATWS, where the concern is to have a
           rewetting of the clad, and will the temperature of the
           clads go up.  And for that, we are actually looking at
           -- we have a fuel code called PROCTRAN (phonetic), and
           we are working with of all things the Fins on a
           subchannel code called GENFLO, and that will allow us
           to look at that phenomena.
                       And we can couple that with the TRAC work,
           but we want to look at other potential generic issues.
                       DR. LEITCH:  I assume -- and not to pick
           on the words, but when you say Torus, I suppose that
           applies to other kinds of suppression pools as well?
                       MR. ROSENTHAL:  Yes, to the extent that it
           was an issue.
                       DR. LEITCH:  And so pool snow and all
           those hydrodynamic effects are also in Mark Iis?
                       MR. ROSENTHAL:  Yes.
                       DR. LEITCH:  Okay.
                       MR. ROSENTHAL:  And we would also like to
           go back and revisit some of what I will term severe
           accident issues.  You have the Mark I liner melt
           issue, and you are now potentially putting down more
           material with more decayed heat in it, and will it
           move out further across the floor and affect the
                       That is something that we ought to look at
           as an example of a severe accident issue that we put
           to bed and that we could take a look at.
                       DR. KRESS:  That was put to bed by the
           peaponus (phonetic) methodology.
                       MR. ROSENTHAL:  Yes.  I doubt if you could
           factor into that the increase through the power level. 
           It is well -- well, the uncertainties are well beyond
           what you get out of that.  I don't know how you would
           do that, but that is your problem.
                       CHAIRMAN WALLIS:  They can try.
                       MR. ROSENTHAL:  I know what you are
           referring to, but I think we have an obligation to try
           to look at the sphere of consideration.
                       DR. KRESS:  Well, you quantify how much
           melt is going to come down.
                       MR. ROSENTHAL:  Right.
                       DR. KRESS:  So you might change that by a
           ratio of 20 percent.
                       MR. ROSENTHAL:  But once it is on the
           floor, it has got more decayed heat.
                       DR. KRESS:  Yes.
                       MR. ROSENTHAL:  And the severe accident,
           the containment venting size for certain power, and we
           can go back and look if it sized with greater power as
           being representative issues that we thought that we
           would rethink.
                       Now, to whatever degree that has already
           been rethought, we don't have to instill again.  But
           that was the scope of the kind of places that we
           thought that we would look to identify issues within
           the success criteria, and within the previously
           resolved generic issues, and within some of the severe
           accident issues.
                       And let me go outside my branch a little
           bit, and some of these things I found interesting. 
           Let me get back to the generator again.  If I am
           pushing more power through VARS, and in fact I have a
           somewhat less stable system electrically.
                       And if I am tripping 120 percent power
           offline rather than a hundred percent offline, that
           potentially also affects the grid.  So I discussed
           that with the PRA people, and they said, yes, those
           things are true, but we don't know how to quantify
           them, or at least now we don't know how to quantify
                       It would be something that we ought to
           look into, and that the risk may be dominated, a
           blackout, by harsh weather events, or external events,
           like seismic events in the past, and so these things
           may not be important.
                       But that is a good illustration of where
           the -- of the feedback between the electrical
           discipline and the thermal hydraulic systems.
                       CHAIRMAN WALLIS:  VARS are reactive -- you
           have kept us in suspense by saying that some thermo-
           hydraulists don't know what VARS are.
                       MR. ROSENTHAL:  We also would like to look
           at the possibility that just electrical equipment is
           going to be running hotter throughout the plant.  So
           the division of engineering is interested in that.
                       And the division of engineering is
           interested in loads and vibrations, and fatigue, and
           thinning, and corrosion, although just as you heard
           just a little while ago, we don't have a good link
           between those issues and the ability to quantify them,
           which maybe be a capability that we would like to
                       With the primary system, we will look at
           things like the vessel, and we will attempt to think
           our way through on piping loads.  On containment
           systems is where I meant to have the cable, and where
           we already have experience.
                       I remember Pilgrim ended up baking a lot
           of cable up in the upper head and having to replace
           cable.  Now, on one hand, just as you heard earlier
           from NRR, there were programs in place to monitor, and
           when people find that stuff no longer works, or it
           gets changed down, that doesn't mean that there is a
           safety issue.
                       But nevertheless we think there are going
           to be issues of thermal fluences and running hotter in
           containment.  I meant to have a bullet under
           containment on the cables specifically.
                       And then of course we are interested in
           the higher pool temperatures and the effect on NPSH of
           equipment.  There may be control systems issues that
           we didn't recognize, in terms of things like steam, to
           condensers, and if that fails, you are pulling more
           steam out and how does that affect the thermal-
                       And the PRA people will look at the human
           response times.  So that is for the human error rate. 
           So that is the scope of the considerations that RES
           would like to do.
                       CHAIRMAN WALLIS:  It sounds big to me.  It
           sounds like a large scope.  What is the funding that
           is anticipated?
                       MR. ROSENTHAL:  The scope of the FY '03
           budget is not out yet.
                       CHAIRMAN WALLIS:  Is this going to be done
           in-house or are you going to hire some consultants?
                       MR. ROSENTHAL:  I have an FTE in the
           branch and some contract dollars that would be a
           little more outside than inside, but yes, we will do
           some of the work inside in-house, through the other
                       CHAIRMAN WALLIS:  Do you have the
           capability to model these systems with your codes and
           computers and it is not a big struggle to get all the
           information that you need to do that?
                       MR. ROSENTHAL:  There is always a loop
           around, and there is always the struggle to come up
           with DAECs.
                       CHAIRMAN WALLIS:  Is G.E. going to give
           you DAECS, or is something going to give you DAECs?
                       MR. ROSENTHAL:  We are planning on using
           an existing one, and for some of these other issues
           that involve that involve either the PRA group or the
           division of engineering, it is obvious that there are
           concerns, and I don't know how we are going to go
           about quantifying them.
                       CHAIRMAN WALLIS:  I think you have a
           management concern.  You have got so many issues that
           you might involve, let's say, a dozen people.
                       MR. ROSENTHAL:  Yes.
                       CHAIRMAN WALLIS:  And you are going to ask
           for a few hours of a dozen people to make an
           assessment which is not superficial, and which is then
           going to be coordinated by some people who can put it
           all together and figure out if it means anything.
                       DR. KRESS:  Jack can do it.
                       CHAIRMAN WALLIS:  So you are going to be
           the guy doing the work and not managing it?
                       MR. ROSENTHAL:  Within the branch which I
           control, we do intend to do it.  I have somewhat
           dedicated resources to work, on at least the thermal-
           hydraulic issues.
                       CHAIRMAN WALLIS:  And when they come in
           front of this committee are they going to give crisp
           answers and not waffle?
                       MR. ROSENTHAL:  The intent is to give yo
           numerical answers.
                       CHAIRMAN WALLIS:  Good.
                       MR. ROSENTHAL:  The last part, you had a
           discussion in terms of the source terms and
           consequence analysis,and we do have the capability to
           generate source terms, and we do have the capability
           to run consequence analysis using math and that was
           not in my mental larva of what we would do at this
                       CHAIRMAN WALLIS:  I think we should keep
           this piece of paper.
                       MR. ROSENTHAL:  And you are going to hold
           me to it?
                       CHAIRMAN WALLIS:  Absolutely.  I will put
           it up on my wall.  When are you going to come and tell
           us, in 2002 or 2003, and we will have a reorganization
           by then, and you won't be in charge.
                       MR. ROSENTHAL:  I would prefer that the
           next time that we would come before the committee
           would be sometime in late Fiscal 2002, when we had
           results of something to show you.
                       CHAIRMAN WALLIS:  Yes, this is a very
           ambitious program.
                       MR. ROSENTHAL:  As distinct from a -- you
           know, I can share the -- well, as I said at the
           beginning, I have to write a program plan, and that I
           would be perfectly willing to do.
                       CHAIRMAN WALLIS:  Well, we see a lot of
           plans, and results are what really matter.
                       DR. KRESS:  I would like to see your
           plans, too.
                       CHAIRMAN WALLIS:  Oh, I know that we would
           like to see plans, but --
                       DR. CRONENBERG:  But this is really one
           FTE, right?
                       MR. ROSENTHAL:  No, no, no.  My branch is
           one FTE, and --
                       DR. CRONENBERG:  And so all the other
           branches have some money for this?  What is the total
                       MR. ROSENTHAL:  As Farouk said, it would
           be 850K and --
                       CHAIRMAN WALLIS:  That's big.
                       DR. CRONENBERG:  That is significant.
                       CHAIRMAN WALLIS:  So it is going to be a
           big fat new Reg report that addresses all these
                       DR. KRESS:  Well, that can be decided
                       CHAIRMAN WALLIS:  Well, there is the
           opportunity to do something like that, and put
           together some really authoritative report which
           addresses all these issues, and finds out the ones
           that are important and gives us some good answers.
                       MR. ROSENTHAL:  I just hope that I have
           not been overly enthusiastic enough.  The thermal-
           hydraulic analysis we can clearly attempt to do, and
           we will do it and get the results, and we will write
           the report on that.
                       CHAIRMAN WALLIS:  Is that first?
                       MR. ROSENTHAL:  On some of the other
           issues like if there is a small incremental change in
           the grid reliability can you actually ever quantify
           what that is, and can you put that back in your PRA,
           I can't make promises on that.  That is really state-
                       And putting in pipe degradation back in
           the PRA is state-of-the-art stuff.  So that is much
           harder for me to make promises on that.
                       DR. LEITCH:  Professor Wallis, I think we
           can deal with additive things intuitively, but I would
           hope that if there are some subtle synergistic effects
           that come to light that we would be made aware of
           those prior to late 2002.
                       And if there are such things that surface,
           that we be notified, because we have been doing a lot
           of thinking about these things ourselves, and we have
           a concern, but I am not sure that we have identified
           any specific synergistic issues.
                       But should there be some, I for one would
           like to be aware of it as soon as you have a sense as
           he does.
                       MR. ROSENTHAL:  At the beginning, I said
           that I have no smoking gun.  If we found a technical
           issue, we would feel obligated to --
                       CHAIRMAN WALLIS:  Well, I don't know if it
           is a smoking gun.  Smoking guns are usually after the
           event.  It is more like a smoldering fire or
           something.  It is something that could grow into
           something important.
                       So thank you very much, and you have
           helped us to get to go to lunch before 12:00 noon.  So
           we will reconvene at one o'clock.
                       (Whereupon, the meeting was recessed at
           11:58 a.m.)
                                A-F-T-E-R-N-O-O-N  S-E-S-S-I-O-N
                                                    (1:01 p.m.)
                       CHAIRMAN WALLIS:  We are now going to hear
           a presentation by ACRS Fellow Gus Cronenberg, who has
           studied the matter of power uprates for a period of
           time and is going to give us some insights on his
                       DR. CRONENBERG:  Okay.  I have two
           presentations, Graham.  I went through this last week
           at a full ACRS meeting, and so what I plan to do is go
           through the margin reduction estimates fairly quickly,
           and then go to the review of some LERs operating
           experience for power uprates for a number of
           incidents, such as the Wolf Creek incident, and Maine
           Yankee, and some of the pipe ruptures that we saw.
                       And some safety implications of those
           operational events.  So I will run through this fairly
           quickly, but this was a chart that ACRS gave me at the
           beginning of the year to try to figure out what are we
           talking about, and their concern about margin
           reductions for the significant power uprates that were
           coming in this year.
                       My overview is basically a little bit of
           margin reductions in the regulatory process, and I
           will go through that real fast; Estimates for power
           uprates, and estimates for renewal, and findings.
                       I think everybody here knows what we are
           talking about when we talked about margins, and it is
           always used in a general sense.
                       For example, when a design criteria in
           10CFR50, it says reactor core and associated coolant,
           control, and protection systems shall be designed with
           sufficient margin to assure acceptable design limits.
                       And we have other various criteria
           throughout Appendix A of 10CFR50.  Again, in
           containment also, including access openings,
           penetrations, et cetera, shall be designed without
           exceeding leakage rates and with sufficient margin.
                       So that basically the rule of law says
           that there shall be some margin that shall not be
           exceeded in nuclear power plant designs.
                       These margin requirements are more
           explicitly spelled out in regulatory guidance and the
           standard review plan, and basically the standard
           review plan for the construction permit essentially
           defines what the margin shall be.
                       Basically, there are pressure limits,
           pressure temperature limits, stress limits, ductility
           limits on cladding, and allowable materials that can
           be used, and then those go down into the ASME, for
           example, and --
                       CHAIRMAN WALLIS:  Gus, limits are not the
           same as margin though are they?  I always thought they
           were two distinct things.
                       DR. CRONENBERG:  Well, basically there is
           allowable margin if you don't exceed these limits.  It
           is basically what the regulatory inspection says, and
           that if you don't exceed a design parameter, then they
           say you --
                       CHAIRMAN WALLIS:  Well, yes, that is one
           view of margin, that it is built into the limit, and
           the other view of margin is that even if you stay
           below the limit, then you have some extra margin, and
           that is the margin that is often discussed; is the
           margin between where you are and where this limit is,
           which itself has a margin.
                       DR. CRONENBERG:  Well, maybe the best
           thing is by example then, and basically a licensee
           will come in with an application and say I have a
           pressure in this -- that my pressure in this piece of
           piping is a thousand psi, and the design limit for
           that by the ASME pressure vessel code is 1,250 psi. 
           Therefore, I have adequate margin.
                       And that is basically all that he will
           say, and the same thing with ductility limits on
           cladding.  I predicted for this amount of burnup and
           I will not exceed 14 percent cladding oxidation, and
           the cladding limits are 17 percent on station limit,
           and I have sufficient margin.
                       DR. KRESS:  But I anticipate that they are
           going to come in and say that the design pressures --
           I don't remember what number you said, but --
                       DR. CRONENBERG:  Well, 1,250.
                       DR. KRESS:  And I anticipate that they are
           going to come in and say that our calculations show
           that our pressure is 1,249.  Therefore, we have
           adequate margin.
                       DR. CRONENBERG:  Well, they will never get
           quite that close, but they will always say in the
           application that we have adequate margin.
                       DR. KRESS:  But that is an example of what
           I think is going to happen, and what should be the
           response to that is that they probably do have
           adequate margin because it is built into the design
           limit like you said.
                       DR. CRONENBERG:  Well, that is for you
           people and the staff to negotiate what that should be
           if it came that close.  And I will show you an example
           where the margin was exceeded in the design.
                       DR. KRESS:  And my own feeling is that
           whether that is adequate margin or not depends on the
           uncertainty of the calculation.  There is a large
           uncertainty in that calculation.
                       Maybe they don't have adequate margin, and
           I think the staff tended to agree with that view and
           said that's why they want to see more, and the closer
           you get to that margin, they want to see more
           uncertainty analysis.
                       Or the flip side of that coin is the
           design pressure for a piece of pipe that is 1,250 psi,
           and yet that piping broke at a thousand psi because it
           had the flow assisted corrosion or something.
                       So, you know, those things do happen, and
           we just passed Aconie, and said there was plenty of
           margin left in the control rod housing, and six months
           later they found cracks.  So even when we think we
           know everything, sometimes we don't.
                       Okay.  Impact of power uprates on plant
           operating conditions and margins.  Basically, for a
           power uprate, you have a coolant enthalpy changes, and
           flow rates, and coolant temperatures, and fuel
           temperatures, and then you have usually some major
           changes to operating conditions on the secondary side.
                       Here are some examples, and as I said, I
           am going to run through this quickly because ACRS has
           already seen this.  What we are talking about here is
           a fleet of aging plants, 25 or 30 years old, that are
           coming in for major power uprates.
                       So this is why the ACRS asked me to look
           at this question of what we are talking about as far
           as pushing these plants further out for license
           renewal, and power uprates, the same fleet of plants
           that have been around for quite a while.
                       And what are we talking about in terms of
           margins.  I used as a case study, and I only looked at
           one, and I am not talking about Duane Arnold today.
                       I looked at a case study, the Hatch,
           because the Hatch had two power uprates.  Hatch is
           under current review for license application, and
           Hatch was also a lead plant, Monticello and Hatch, for
           the G.E. extended power uprate program.
                       It is an older plant, an early '70s
           vintage plant, BWR-direct cycle Mark-I containment,
           two power uprates in '95 and '97.  And it is also
           under current review for license application.
                       So I looked at what the impact of those
           two separate actions on the plant, and basically we
           have a direct cycle plant, and so what I did was march
           around the primary system, and the secondary system,
           and see what I could see as far as design parameters,
           and changes in design parameters, and therefore
           changes in margins.
                       For recirculation, piping, the feed water
           piping, the primary steam piping, and that sort of
           thing, and what was the impact of the power uprates
           and the license renewal on those kinds of systems.
                       Okay.  Here is -- and I don't know if you
           can see that clearly, but these are the powers for
           unit one and unit two.  They are sister units, and
           essentially the same power, and what was changed.  For
           example, the steam flow rates were increased from an
           original 10 to 10.6, to 11.5; and steam dome pressure,
           the original was 1015 and then it jumped to 1050, and
           then a constant pressure type of uprate to 1050 again
           on the second power uprate.
                       The temperatures changed from the first to
           the second, and of course the feedwater flow rates and
           temperatures increased progressively as you went up in
                       There were two types of margins, and I
           wrote down operational conditions, and then also what
           are the changes in margins for design basis LOCA
           conditions; and that I also looked at fatigue
           estimates for the license renewal from the time
           limited aging analysis.
                       My margin was based on what I would call
           a definition of -- well, it doesn't say there shall be
           adequate margin, and that is what the rule says, 10
           CFR 50.
                       Basically, I said that you can't exceed
           the design limit from the ASME pressure vessel code. 
           So the operating parameter scaled to the design
           pressure, or design temperature, or whatever.
                       Okay.  The main steam line pressure, we
           saw that increase from 1015 to 1050, and the design
           limit for that piece of piping is 1250 psi.  So we had
           a margin of 18 percent when we built the plant, and
           reduced to 16 percent.
                       So there is a 2 percent degradation in
           margin, and one would say that is not much of a
           decrease in margin.  The same with steamline pressure. 
           The design pressure or design limit for that piece of
           piping is 1575, and we go from 546 to 551.
                       So we go from 5 percent to 4 percent
           margin, and of course, from what Dr. Kress said, there
           is also excess margin above the ASME allowable design
                       Feed water piping, and 1650 is the design
           limit, and we go from 1130 down to a lower pressure,
           and then the feedwater piping temperature we increase. 
           So we go from 30 percent margin to 28 percent margin.
                       So nothing major so far here as far as
           operational conditions.  However, if we start looking
           at LOCA conditions, things change a little.  The
           reductions in predicted margins become greater, and
           when I get into my next set of slides, we will look
           at, for example, the Maine Yankee experience, which
           was not a very pleasant experience.
                       But that was as you know related to a
           power uprate for Maine Yankee.  They could not quite
           satisfy their LOCA conditions, and I will get into
           that story in a little while.
                       DR. SCHROCK:  And when you are talking
           about percentages, they are based on what?
                       DR. CRONENBERG:  Just the design limit
           over the value, and how the value changed as a
           function of power.  We went from whatever it was --
           well, from 392 to 4000.
                       DR. SCHROCK:  And do you need sort of an
           absolute number denominator?
                       DR. CRONENBERG:  Yes, it is.  It is the
           562.  It is the design limit.
                       CHAIRMAN WALLIS:  And we could make it
           degrees --
                       DR. SCHROCK:  Yes, that is what I was
           getting at.  You can get a different answer if you use
                       DR. CRONENBERG:  Oh, I see.  I just used
           -- it is specified in terms of degrees fahrenheit, the
           design limits, and so that is what I used it as.
                       DR. SCHROCK:  You probably shouldn't
           express it as a percentage.
                       DR. CRONENBERG:  Well, this is just a
           signature.  I am trying to give a feeling for what
           things are changing, and --
                       DR. SCHROCK:  I know what you are trying
           to do, but the significance of the number should not
           be dependent on an arbitrary choice in the system of
           units that you want to use.
                       DR. CRONENBERG:  Well, margin is in and of
           itself kind of an arbitrary term used in the
           regulatory process, and we will never find a
           definition of you can't exceed a parameter by .2
           percent or something.
                       You do have things in terms of allowable
           dose limits, and that sort of thing.
                       The only things that we have are design
           parameters in the boiler and pressure vessel code, or
           curies, or dose, or something like that.
                       Okay.  Here is some predictions for the
           Hatch plant on the design of LOCA calculations.  For
           example -- I wanted to go to the primary system  first
           -- here is one for the vessel shroud and support weld,
           the vessel shroud and head bolts, and the access cover
                       All right.  The vessel access cover plate,
           et cetera.  Now, all these numbers I got from the
           licensee's own submittal, okay?  The safety analysis
           report, the SAR, and the SER.  I didn't go beyond
           that.  I just used the licensee's own numbers.
                       And, for example, the predicted stress at
           the original power at the support welds was 8.9
           kilopounds per square inch, and it jumped to a 9.05. 
           So not much change in margin there.  The same for a
           head bolt.
                       Now, this access hole cover plate is an
           interesting comparison, because it looks like with an
           8 percent power uprate; that between the first uprate
           and the second uprate that there was an 8 percent
           power increase.
                       The predicted stress jumped from 64 to 90,
           but that is a little unclear because -- and one of the
           conclusions that I am going to  make in  my
           presentation today is that I don't think either the
           safety analysis report, nor the NRC's safety
           evaluation report, the SER and the SAR, give you
           enough detail and enough information to do a good job
           on margin assessment.
                       I don't know if it is the number one bolt
           in the first calculation, and the number six bolt in
           the second calculation.  I don't know if you had
           superimposed loads.  I don't really know if one was a
           seismic induced and one was not a seismic induced.
                       You don't get in the SAR a picture of the
           EISO bars for the stress predictions for all the
           components.  All you get is a little summary table
           saying that these were my predicted stresses for these
           5 or 6 components.
                       And then the SER basically says that we
           had no problems or we requested information on this
           particular number.
                       So if ACRS is asking for a detailed
           assessment of the impact of a power uprate on margins,
           I can't pull it out from the data that I worked out
           from the historical FSARs.
                       And there is no defined criteria; that
           this piece of information shall be given for this
           component every time you do an uprate, so that you can
           compare apples and apples, and so you can get an
           historical picture of what is happening to this
           reactor over time, and for the various licensing
                       Also, you change models and you change
           calculational procedures, and there is not enough
           detail in what we get I believe from the applicant, or
           what I can find out in the evaluation report by the
                       So I don't know how we are going to get a
           good handle on margins if that is what this committee
           is concerned about, and that will be one of my
           conclusions.  The information base to me is sketchy.
                       DR. FORD:  Just to go back through that,
           did you ever resolve the question of whether the --
                       DR. CRONENBERG:  No, I looked back and I
           couldn't tell which bolt it was for, and I couldn't
           tell the exact details of the boundary conditions on
           the stress calculation.  There was not enough detail.
                       What I can tell you is, and what I told
           you before, that access plate was replaced because of
           what was found at Peach Bottom.  They found stress
           corrosion cracking in the welding of that plate, and
           then the NRC required that they do inspections at each
                       And the licensee, because the inspection
           program was going to cost them so much, they decided
           to just replace that access cover plate.  I don't
           think it resulted from these kinds of numbers.
                       But from my reading, I couldn't get a good
           indication of what are the boundary conditions in the
           stress calculations.  They are not discussed in the
           submittal, and they are not really discussed in the
           evaluation report.
                       But all I saw was tables and these are the
           numbers, and it is probably hard to go back to
           something in '95 and ask for that contractor report. 
           Sometimes it is not even the licensee.
                       The licensee will go to G.E., and G.E.
           will go to Structural Analysis Associates, and I will
           show you some of what you have to backtrack to pull
           the information out when we get to the time limited
           aging analysis.
                       It was not easy to pull information to get
           these numbers.  And then we had the same thing on the
           margins on the LOCA conditions for the containment,
           and for the drywell pressures, we go from a 14 percent
           margin down to a 10 percent margin.
                       In some cases the peak drywell gas
           temperature exceeds the design limits, but you look at
           the calculations, and it is for a short period  of
           time.  So the NRC says that's fine.
                       It is only for a short period of time, and
           it is basically a few seconds in this calculation
           during the flow-down, and the exemption is still
           granted, and you can't go up in power.
                       And then the same suppression pool
           temperature, of course, and the temperature goes up
           because you have higher power, and the margin goes
                       But there is nothing major here so far,
           except for what we saw for that access cover plate. 
           Since I am interested in the license renewal, I think
           you can get a better handle on margins.  There is more
           requirements that go into a license renewal
           application going from 40 to 60 years operation
                       We have a standard review plan that is
           based on several years of agency efforts between the
           staff and ACRS going back and forth on what will be
           required for an adequate submittal on license renewal.
                       And there is a lot of calculations there,
           and you can calculate margin, and it is more clearly
           documented.  It is easier to pull out something on
           margin reductions if it is more clearly documented.
                       Basically, I looked at the time limited
           aging analysis, and we talked about this this morning,
           and the cumulative usage factor for the questions of
           fatigue that Peter was bringing up.
                       And we heard a response from the NRC staff
           that for these uprate applications that the staff is
           requiring some cumulative usage factor estimates.
                       And then I said that was the first time
           that I had seen from the applications that I looked at
           in the past, and I never saw any cumulative usage
           factor estimates for pipes or any real components.
                       And this was new to me, and I think it is
           a good way to at least get a handle or a feeling for
           degradation and the effects of increased flow, and
           increased vibration, aging, and that sort of thing.
                       And accumulative usage factor is just a
           fatigue estimate, and basically it is based on
           historical data, and then projecting that out in time.
                       And we can see what the estimates are for
           the heat removal suction piping at 40 years, and
           basically you can't exceed one, and if you calculate
           one, then you have to do something for that component.
                       It is essentially from the agency's point
           of view it has filled up its bucket as far as fatigue
           in Ralph's analogy of a bucket.  So we have some
           buckets for irradiation induced embrittlement, and we
           have buckets for fatigue, and so forth.
                       We have some buckets that we fill up for
           pressure temperature limits, and for license renewal,
           I don't know how many buckets we look at for the power
           uprate.  It is not as clearly defined for me.
                       And then you can estimate it for 60 years,
           and so your residual margin here went from 43 to 23,
           and feedwater piping has a margin of 39 percent down
           to 17 percent.
                       It looks like if this is an accurate
           prediction of what is happening over time, then you
           did increase your fatigue on that piping, and you
           reduce margin.
                       It is something anyway, but to get these
           estimates, these cumulative usage factors will not or
           are not part of the licensee submittal.  They are not
           a part of appendix material.
                       This was referenced in Appendix C of the
           license submittal.  I asked for these numbers from the
           staff, and we couldn't find them.  I had to go back
           and go through Brent Busher, and he had to go back to
           the licensee.
                       And the licensee had to go back to the
           subcontractor, to G.E., to get these numbers.  That's
           why I am saying that sometimes it is hard to pull this
           information out.
                       If this committee wants to know something
           and this agency wants to know something about margins,
           it is going to have to define what is required and
           what kind of information we are going to keep.  Right
           now we don't have a clear definition of that.
                       The pressure temperature limits were in
           the Appendix E of the license renewal application for
           the Hatch plant, and we did have those numbers in-
                       And basically that if you have a certain
           pressure of a piece of piping, you have to have a
           certain temperature to keep that pipe ductile enough.
                       And because of irradiation embrittlement
           the ductility is going down with irradiating dose and
           time, and so the temperature has to get and higher,
           and higher, and higher.  So these are estimates in
           Appendix E of the license renewal for 36 effective
           full power years, 40, 44, 48, 50.
                       We go from a margin of say about 30 to
           half that at 60 years.  So to me there is a clearer
           indication of margins and how they are affected for
           the license renewal, because we thought about it, and
           we thought it through over a number of years, and we
           know something about aging, and fatigue, and flow
           assisted corrosion.
                       And we asked the licensee this is what you
           have to submit to us to show that this plant will be
           good for another 60 years, and have we clearly thought
           that through for significant power uprates for an aged
           fleet of plants, and that is the kind of question that
           I think is really before this committee.  What does
           this agency need to be looking for.
                       Okay.  These are just data sources. 
           Again, I wanted to really indicate to you that you
           have to look at a lot of different data sources.  It
           is not easy to pull all of this together, because
           every licensing action is an individual action.
                       We look for a power uprate in an
           individual way.  We look for extended fuel burnup as
           an individualized licensing action.  We look for a
           license renewal in that individual licensing action.
                       No one puts this all together in terms of
           margins for the plant as a whole.  The point of this
           slide is that this is all the information that I got
           out and it was proprietary information as an appendix
           to the LOCA calculations for the Hatch SAR, and these
           were the stress calculations.
                       It is a summary table and very little is
           told you about the boundary conditions, the models,
           and so forth that I used in there.  So it is hard to
           predict from one power uprate to another, because they
           will give you different components or different bolts,
           or whatever.
                       So the task that you asked me to do was
           almost an impossible task to give you a clear answer,
           because we don't have clear dictates on what is
           required on calculational results.
                       It is just tell me what the maximum stress
           is for a couple of components, and that is basically
           what you get in a summary report.  The analogy to me
           is when we went to the IPEEE process.  We didn't ask
           for the dependency tables in the PRA.
                       All we asked for is a summary report, and
           then we tried to glean information out, and it was
           hard to pull, and then we started asking questions. 
           Well, what does this mean.  Well, we only have summary
           reports and we don't have dependency tables.
                       DR. FORD:  So do the stresses change?
                       DR. CRONENBERG:  The loads are different
           because the blowdown loads are different because of
           the power increase.  The coolant enthalpy is increased
           and the blowdown loads are increased.
                       DR. BOEHNERT:  Gus, you should probably
           pull that slide.  That is proprietary material and we
           are in an open session.
                       DR. CRONENBERG:  Okay.  Sorry.  And a lot
           of this information is also proprietary.  All right. 
           Summary and observations to date.  Safety margins are
           used in a very broad sense and in the regulatory
                       And there is a lot of difficulty in
           getting consistent data to assess the margin impact.
           Different models change, and things that are looked at
           change from one uprate to another.
                       There was some success nevertheless from
           Hatch, and that's why I titled my talk "Signatures of
           Margin Estimates and Margin Reductions."  We get some
           sign posts here and there of what is going on but we
           don't have a good integrated assessment of what the
           margin impact is for that whole plant.
                       You can't tell if it is a synergy and you
           get it for a piece of pipe or a bolt, or something,
           but it is not the plant as a whole.  Generally though
           as you might expect from the start before we even
           looked at this, that there is some reduction in
           margins because you increase power and you increase
           LOCA based stresses.
                       And you increased pressures and
           temperatures on piping and that sort of thing.  So
           there is some indication of a degradation in margin
           from design limits.
                       And also I believe the SARs, and what we
           are requiring in the SARs and the SERs do not appear
           to be of sufficiency, detail, and consistency to make
           a good assessment of a margin impact on this
           particular licensing action.
                       I think that the data is too sketchy to
           give you a good feeling for margin.  Basically you
           will see in the SER and what -- and basically all the
           agency is required to do is to assess the current
           regulations are satisfied.  That is what we regulate.
                       The kinds of concerns that this committee
           has, you go, well, will we be caught in the Maine
           Yankee situation, and you look at it in a little
           broader sense.
                       What is the real safety impact, and so the
           questions asked by this committee are probably a
           little different than the questions asked by the
                       And to answer the questions that the
           committee has asked me to look at is -- well, you
           can't get a clear answer as to that.  I do have some
           suggestions on power uprates, and these are
           observations, personal observations and suggestions
           that tell me what should be asked for.
                       Basically, the NRC uprate review process
           centers on the assessment of current regulatory
           requirements are satisfied.  There is no requirements
           for risk impact, margin reductions, or impact of
           multiple licensing actions and synergies.
                       It is just that the current regulatory
           requirements are satisfied, and that is rightly so
           what the staff should be looking for.  Nevertheless,
           I endorse prior recommendations from the Maine Yankee
           lessons learned report.
                       You know about the Maine Yankee history
           here, and one of the principal conclusions of the
           lessons learned was that we need a standard review
           plan.  We need some sort of guide post, and the G.E. 
           uprate and extended power uprate is one step in that
                       And basically for the PWRs, the last thing
           we had on the power uprates was for guidance, and we
           never had a guidance from CE, and we never had
           guidance from BWR, and we only have a W-Cap report
           from 1984 for the Westinghouse.
                       And that is the last time that we had
           guidance come in from vendors on what it takes to do
           a power uprate for a PWR.  PWRs still follow the W-Cap
           guidance from 1984 that Westinghouse provided, which
           is a very minimal -- it is like a 10 page report.  It
           just lists the kinds of things that you might look at.
                       Also, Scitech did a review for research,
           or it was for NRR or research, but it was a contractor
           report, and to do a review of the uprate applications
           to that time, and the Scitech conclusion also
           concluded that this agency would be better served if
           it had a standard review plan.
                       It looked at large variances for one
           upgrade application to another, and the review
           procedures, and there was no clear definition of
           acceptance criteria, and why you looked at this
           control rod drive.
                       In one case, you didn't look at control
           rod drive calculations, and on another you looked at
           fuel behavior effects, and on another you did not. 
           Scitech's conclusion was basically that there was no
           clear guide posts for a review of uprate applications.
                       And they also endorsed a standard review
           plan, and the same with my 1999 recommendation, I also
           thought that this agency would be better served if it
           had a standard review plan in place for power uprates.
                       DR. LEITCH:  In spite of all those
           recommendations, we seem to be moving forward without
           such a standard review plan.
                       DR. CRONENBERG:  Partly because most of
           them, I guess, are for G.E. so far, and G.E. is ahead
           of the other plants.
                       DR. LEITCH:  Yes, but the recommendations
           stemmed largely from Maine Yankee, which -- and as you
           said, it is more applicable to BWRs.
                       DR. CRONENBERG:  Again, an uprate standard
           review plan might include a standardized listing of
           all system structuring and components subject to an
           uprate review.  It kind of mirrors the kinds of things
           that we have in a license renewal application.
                       Assessment of impact on system structures
           and component margins for both operational and DBA
           conditions.  A clear definition of methods to be used
           and acceptance criteria that the staff will review
           that application.
                       That is the kinds of things that we have
           in the license renewal application.  We don't have a
           clear definition of, for example, acceptance criteria
           for the staff to review.
                       We have input from G.E. on what they will
           submit, but do we have a clear definition that this
           committee is comfortable with as far as acceptance
           criteria for the review of that application.
                       I also talked about something that I
           called the legacy tables, and it is some sort of time
           line or history of what is happening with that plant
           as you go on in time, and as you uprate power.
                       Right now we don't have that a licensed
           application for an uprate will include what was on the
           prior power, and what was on the original FSAR, and
           what changes were made as far as fuel burnup, and how
           that might have impacted the same components, and
           structures, and systems that are impacted by the power
                       And a standardized table for DBA predicted
           loads.  We do have these kind of standardized formats
           that one has to follow in our license renewal process. 
           We don't have it for the proper uprate process.
                       So that is basically what I wanted to say
           about margins, and then I have a second talk that I
           was asked to do on looking at uprates, and past uprate
           applications, and events that occurred for plants that
           had received uprate approvals.
                       And so are there any questions at this
           point on margins?  Now, this work I did back in '99,
           and again I was asked to review uprate applications
           and see if there was a potential synergistic safety
                       And the way I approached that is that I
           looked at operational events for uprated plants.  I
           will review some of those applications and NRC review
           procedures, and altered plant conditions, events noted
           for uprated plants, potential synergistic safety
           issues, and observations and recommendations.
                       And some of this I guess I can skip here. 
           These are the uprate applications up until the early
           or mid-1990s.  I think there was something like 21
           uprates, and most of them are 4 or 5 percent power.
                       Those are the kinds of applications we
           used to see in the mid-1980s and early '90s.
                       DR. FORD:  You have Oyster Creek there and
           there are three really quite big ones.  Any reason why
           those are big ones and how they got through at that
                       DR. CRONENBERG:  Well, Maine Yankee was
           one, and Indian Point.
                       DR. FORD:  Indian Point was PWRs and that
           was 10 or 11 percent?
                       DR. CRONENBERG:  Some of them, and I am
           not sure, because it has been a while, Peter.  But
           some of them were asked to go to a certain power
           level, even though the design base or the FSAR
           calculations were all based upon higher power levels.
                       And I would have to go back and look and
           see which of those plants were, but some of them --
           all the FSAR calculations were done at a certain power
           level, and their original operating license was for a
           lower power level than their design basis
           calculations, and they are allowed to step up to
                       DR. BOEHNERT:  Certainly Oyster Creek was
           one of those, and I bet you that the other two were as
           well.  Indian Point was the other one, and Maine
                       DR. CRONENBERG:  I don't need to go
           through that plant.  Okay.  What I am going to
           concentrate on are the power uprate events.  Now,
           maybe I shouldn't use this term, but these events that
           happened for power uprated plants, whether they were
           due to the uprate or something else.
                       It is not always an easy story to pick
           out.  The first one you know about, the Maine Yankee
           one, and that went for two power uprates.  There was
           a deliberate faulty LOCA analysis submitted by the
           licensee that involved the critical heat flux and
           alteration of the decay heat models.
                       It was a whistle blower type of notice
           that came before the agency.  The whistle blower went
           to the State Agency, and the State Agency came to the
           NRC after the uprates had been approved.  There was
           two of them.
                       Both incorporated faulty analysis, which
           was not caught by the NRC and only after we received
           insider information from the whistle blower.
                       Wolf Creek and North Anna, both of those
           had uprates, and there were control rod insertion
           problems noted in high power hot, and high burn up
           assemblage.  And we will go through that.
                       There was the Callaway and Susquehanna,
           which were pipe ruptures, and a long history of all
           kinds of pipe ruptures in nuclear power plants, and I
           will go through some of that.
                       Brunswick was a faulty use of DBA
           criteria, and then we have Limerick instability
           problems.  Okay.  In Maine Yankee, we had allegations
           of a deliberate faulty LOCA analysis submitted by the
                       The DBA declared limit of 2,200 was
           exceeded for uprate conditions, and the LOCA analysis
           was performed for altered decay heating critical flow
                       The NRC did not question the licensee's
           analysis, and there was no really audit calculations
           using our own audit codes of the licensee submittal. 
           However, after the allegation was submitted to the
           agency, we did an internal study and we verified that
           indeed there was a faulty analysis submitted by the
                       Maine Yankee was shut down and never
           operated again.  The lesson learned from Maine Yankee
           was a need for independent staff analysis or audit
           calculations, some of which Ralph talked about this
           morning, and that the NRC at this time is aggressively
           doing some audit calculations for these type of power
           uprates, and which was not done during the time frame
           of the Maine Yankee.
                       DR. LEITCH:  Just one point of fact.  When
           you say it was shut down and never operated again, it
           was reduced to the pre-uprate power level and did
           operate at that power level for quite some time.
                       DR. CRONENBERG:  Okay.
                       DR. LEITCH:  And for quite some time I
           mean a year perhaps.
                       DR. CRONENBERG:  A year, and then they had
           to upgrade their ECC and they decided not to do it for
           one reason or another and the plant was shut down.
                       DR. UHRIG:  I thought it was steam
                       DR. LEITCH:  There were a number of
                       DR. CRONENBERG:  And I think that the
           injection system was not adequate for the LOCA.
                       DR. LEITCH:  Yes.
                       DR. CRONENBERG:  Wolf Creek and North
           Anna.  Wolf Creek had a --
                       MR. ROSENTHAL:  Can I just interrupt for
           just a moment, please.  Jack Rosenthal.  I was on the
           Maine Yankee independent safety assessment, and I led
           the team at Yankee Atomic while most of the team was
           up at Maine Yankee.
                       And we reviewed all different sorts of
           analyses, the higher scope of Chapter 15 analyses, and
           were generally satisfied with a broad range of
                       And I believe, or from what I understand,
           that the reason that Yankee did not ultimately
           continue operation were questions concerning its steam
           generators, and it had done a hundred percent plugging
           of the sleeving of the steam generators.
                       And they were faced with a financial
           question about replacing the steam generators, and
           cable separation issues that dated back a long period
           of time, and they were faced with a large cost of
           replacing the steam generators.
                       It was in a State in which there had been
           referendums in the past on whether the plant would be
           allowed to run a lot.  So there was a great deal of
           financial uncertainty associated with the plant, and
           so they made a business decision to shut down the
                       And in fact if it was only the LOCA
           analysis, that would have been readily overcome by
           either them doing the analysis or going to still a
           third party.
                       And their large break LOCA analysis was
           always a combustion evaluation model.  It was a small
           break LOCA issue.  So I think in the characterization
           of Yankee, it would be fair to say that they
           ultimately made the decision to shut down the plant
           for commercial reasons.
                       DR. CRONENBERG:  My point was that the
           small break LOCA calculations were submitted, and we
           accepted them, and then after we had the allegation,
           we audited those calculations and found that, yes,
           indeed the models were altered.
                       And we didn't catch that in the review,
           and that was my main point.  The Wolf Creek and North
           Anna, we had an uprate in 1996, and this is PWR plant,
           with Advantage 5H type of fuel assemblies, and
           basically they had a control rod insertion problems
           for the high power, high burn-
           up assembly, and basically the thimbles swelled due to
           irradiation growth mode, and then the control rod
           couldn't be placed down into those thimbles again.
                       I would like to read you what was -- well,
           because it happened in high power, high burn-up
           assemblies, it could have been reviewed as part of the
           power uprate application and I just wanted to read
           here what was in the SER on the control rods.
                       The only thing that was looked at was the
           control rod drive mechanisms as far as the
           documentation of the review.  The licensee evaluated
           the adequacy of the control rod drive mechanisms by
           comparing the design basis input parameters with the
           operational conditions for the proposed uprate.
                       The licensee stated that he uprate
           conditions would have an insignificant impact on the
           original design basis analysis for the control rod
           drive mechanism.
                       The staff has reviewed the licensee's
           evaluation and concurs with the licensee's conclusion
           that the current design of the control rod drive of
           the control rod drive mechanism would not be impacted
           by the uprate.
                       That is the only thing on control rods
           themselves, and at least from the review procedures
           the thimbles the irradiation growth.  There is nothing
           telling me in here, and it just says the staff
           reviewed the licensee applications.
                       I had no idea of what the acceptance
           criteria of that is.  It just said we reviewed it and
           find it acceptable.  I think with a little more
           tightened review procedures, where we define what the
           acceptance criteria are, just like we do on a
           construction application.
                       And that we would be better served, and
           that the staff will have a better guidance as to what
           is acceptable and what isn't acceptable.  So we had an
           incident at Wolf Creek, and all you can say that it
           did happen, and with the high power assemblies it
           might have been a review question, but we looked
           mostly at the control rod drive mechanism.
                       We didn't say anything about irradiation
           and induced swelling of zurcoroid guide thimbles.  And
           maybe if we had a standard review plan we would say
           that this is what you have to look at, and these are
           the kinds of calculations that you have to make with
                       And you have to monitor and this is the
           acceptance criteria, and you shall not have such
           swelling, and so forth, and so on.  On North Anna, we
           had -- and this is again a PWR, and we couldn't insert
           new rods into assemblies that were being stored in the
           spent fuel pool.
                       They tried to bring in some new control
           rods, and insert them into the assemblies that they
           had in the spent fuel pool, and those guide thimbles
           were also warped, and we couldn't temporarily store
           the new control rods into those assemblies.
                       Neither uprate SER addressed changes in
           fuel rod or control rod performance for high burner,
           high power conditions.  The lesson learned here again
           is that maybe we need something -- a tighter review
           process for power uprates.
                       Okay.  Pipe ruptures.  We talked about
           corrosion and erosion problems, flow assisted
           corrosion.  We had many pipe ruptures.  We have 53. 
           There is an IPEEE report, a detailed IPEEE report on
           pipe ruptures, and we have 53 pipe rupture events for
           pipings greater than 2 inches in diameter.
                       Most of those were attributed to an
           erosion/corrosion mechanism as Peter noted this
           morning, and erosion is a flow, a flow synergism, and
           corrosion is an aging phenomena, and here we have a
           synergism or a linkage with enhanced degradation of
           flow assisted corrosion process.
                       Empirical evidence for flow/aging effects,
           lessons learned, is a need for a staff review of
           potential synergisms, and this is --
                       DR. FORD:  The 53, is that 53 between how
           many plants?
                       DR. CRONENBERG:  I have a table coming up
           on that.  Basically, I just took that from an EPRI
           report.  It is not anything that I did.
                       Nucleonics Week.  I just wanted to talk
           about the Susquehanna shutdown, and this just came up
           this morning, and there were some statements that it
           was more than just maybe a flow associated vibration
                       But I just wanted to quote the headlines
           from Nucleonics Week with respect to Susquehanna.  "A
           recent Susquehanna-2 forced outage could be the result
           of weld fatigue from increased vibrations from a power
           uprate in 1995, and NRC is looking at potential
           generic implications for other uprated BWRs."
                       "BWR uprates have increased the speed of
           recirculation pumps and caused increased vibrations in
           the recirculation systems, said the NRC resident
           inspector at Susquehanna."
                       The reason that I put this slide up is
           that this is the only time that I see anyone really
           stating what they believe is a direct linkage between
           an uprate and a pipe rupture.
                       MR. KLAPPROTH:  This is Jim Klapproth with
           G.E.  I would like to comment on that.  We saw that
           article come out and we do not agree with that
           position.  Really, there was an increase of flow, and
           Susquehanna moved to an increased core flow
           concurrently with the power uprate, but it was not
           specifically a power uprate issue.  It was increased
           core flow.
                       DR. CRONENBERG:  Okay.  But the --
                       DR. FORD:  Well, 53 is an astounding
                       DR. CRONENBERG:  And 53 isn't just from
           flows.  I put this up because this was a statement by
           an NRC official that an event, an LER to uprate.
                       MR. KLAPPROTH:  I understand, but I would
           just like to go on record as saying that G.E. does not
           agree with that position.
                       DR. CRONENBERG:  I understand, but you do
           agree that it was a flow enhanced flow, but the flow
           was not dictated by the power uprate?
                       MR. KLAPPROTH:  It was not due to power
           uprate, yes.
                       DR. CRONENBERG:  And here is a piping
           rupture mechanisms through 1995, and basically EPRI
           did this for the Swedes.  The Swedes wanted some
           information on pipe ruptures, and what are the
                       And so they did it for a range of piping
           sizes.  It was according to small piping, larger than
           2 inch piping and that sort of thing.  Erosion and --
                       DR. LEITCH:  This surely isn't primary
                       DR. CRONENBERG:  No, this is all piping in
           the plants.
                       DR. LEITCH:  This is piping in nuclear
           plants that ruptured?
                       DR. CRONENBERG:  Yes.  And the EPRI report
           is a real detailed report on pipe ruptures in nuclear
           power plants, but you can see the highest here for
           vibrational fatigue and erosion/corrosion, both of
           which one might expect vibrational fatigue for
           increased flows, and erosion/corrosion for higher
           powers and higher flow rate that might accompany a
           power uprate.
                       To me, this indicates that most from our
           experience to date, that most of our ruptures for
           large piping, and this is 2 inch and above piping, are
           for kinds of phenomena that we would see in an uprate;
           vibrations due to flow, and flow assisted corrosion.
                       DR. KRESS:  If I have got a hundred plants
           out there, and I look at vibration frequency, and
           there is one a year?
                       DR. CRONENBERG:  Yes, one a year.
                       CHAIRMAN WALLIS:  I am trying to relate to
           your previous thought.  You said it was erosion
           problems, and presuming it was carbon steel pipes,
                       DR. CRONENBERG:  Yes.
                       CHAIRMAN WALLIS:  And yet you said there
           were 53 events of erosion/corrosion of carbon steel
                       DR. CRONENBERG:  Well, 53 events for pipe
           ruptures greater than two inches.  That could e all
           types of ASME type designations of all kinds of
           piping.  Basically, it is steel piping, but 53 large
           pipe breaks.  Now, on this slide --
                       DR. LEITCH:  And worldwide presumably,
           because you have a foreign plant listed there.
                       CHAIRMAN WALLIS:  That's right.
                       DR. CRONENBERG:  Yes.
                       DR. KRESS:  And if I add up all of those
           listed over there, I don't get 53.
                       DR. CRONENBERG:  This is just the
           breakdown of where you see these breaks, okay?
                       DR. KRESS:  But those are just U.S.
                       DR. CRONENBERG:  I have to go back.  I
           don't know if they are just U.S. plants, Tom.  I have
           to go back into the EPRI database.  They did it for --
           I can get you a copy of that.  They did it for the
           Swedes.  It might have included other plants.
                       DR. KRESS:  But if you add it up and
           multiple it by a hundred plants, it doesn't add to
           very many.
                       DR. CRONENBERG:  No.
                       CHAIRMAN WALLIS:  Three a year.
                       DR. KRESS:  I forgot about multiplying it
           by the number of years.
                       DR. FORD:  Previously, you said that
           Callaway and Susquehanna, and I assume you are
           referring to erosion/corrosion problems in the carbon
           steel pipeline, and you said Guillotine pipe failures?
                       DR. CRONENBERG:  Yes.  Well, no.  Did I
           say Guillotine?
                       DR. UHRIG:  Yes, you did.
                       DR. CRONENBERG:  Sorry.  Susquehanna was
           not a Guillotine.  Susquehanna was on a line to the
           recirculation system.  Callaway was a large pipe --
           somehow will have to help me.  Do you know what the
           Callaway was again?  I will have to go back and give
           you an answer on Callaway.
                       DR. FORD:  Maybe you could relate to how
           many gallons per minute you are losing in heat.
                       DR. UHRIG:  It is Callaway and Susquehanna
           guillotine pipe rupture.
                       DR. CRONENBERG:  Yes, Guillotine should be
           out of there.  And in the DBA analysis of the wet weld
           design limit is 220 and NRC did not challenge the
           licensee's evaluation at 220.  However, the real
           number should have been 200.
                       So it was just an oversight that got
           through, and the licensee then came back and said,
           sorry, it should have been 200 and not 220.  It is
           just an example of something that we didn't catch.
                       Where if we had a more detailed or
           checklist, and again I am trying to say that we would
           be better served if we had a tighter process, a
           standard review plan, and maybe these kinds of numbers
           would be in there, and we would not have been caught
           in this type of situation.
                       And where we didn't catch it and the
           licensee had to come back and say that we didn't catch
           it, and you didn't catch it, and we did catch it.
                       And then Limerick, and we have these --
           well, when we restart, we have these instabilities
           that we see for BWRs, where the predicted Delta-K over
           K is different from the measure, and it gives the
           operator a little bit of heartburn when he sees that.
                       And then we have to back off on power, and
           then find out what was wrong with our calculations,
           and then start up again.
                       DR. UHRIG:  I didn't understand that. They
           are not determining a design limit are they?
                       DR. CRONENBERG:  Which one do you have
           questions on?
                       DR. UHRIG:  On Brunswick.  You had
           licensee based on wet weld design limit of 220, and
           NRC did not challenge the 220.  I thought the NRC
           would set the limit.
                       DR. CRONENBERG:  In the FSAR, the design
           limit for the wet weld for that plant was 200 degrees
           F.  The analysis was based at if the design limit was
           220, and it was submitted by the licensee.
                       We believe that our design limit for a wet
           weld is 220, and NRC went and said, yes, we reviewed
           the application, and you are below 220.  It is fine. 
           A couple of months later, the licensee came back and
           said, oh, sorry, I told you the wrong number for the
           design limit.  The design limit was 200.
                       What I gleaned from looking at some of
           these LERS, license events for uprated plants besides
           the generic implication of a need for a tightened
           review process, and a standard review plan, is that
           maybe there are synergisms.
                       For example, rod fretting, and flow
           induced rod vibration, leading to contact wear  with
           adjacent structures, and increased core flow at
           uprated powers, and zry-irradiation growth.  We know
           that there is irradiation growth, which may lead to
           some fretting problems.
                       Axial power offset.  We know about the
           axial power offset problem, and boron added to
           compensate for excess reactivity for high burn up and
           high enrichment, crud buildup for long fuel duty
           times.  And boron is gettered.
                       There seems to be evidence of boron
           gettering by the crud, and we have an axial power
           offset.  The effect is compounded, and it seems to be
           the evidence that it is compounded at high-power core
                       DR. UHRIG:  Where is that evidenced?  I
           have not heard that before.
                       DR. CRONENBERG:  The boron?
                       DR. UHRIG:  No, the effect that it is
           compounded by high-power.
                       DR. CRONENBERG:  Mostly, they find it at
           the high-power central locations and don't find it at
           the lower power assemblies.  It is something that we
           look at for high burn up assemblies.
                       Other synergisms, and Jack talked about
           these, and looking at cable degradation, insulation
           breakdown due to irradiation effects, and that is
           exacerbated by elevated temperatures.
                       We do have cable aging type of things in
           our license renewal requirements.  However, if we are
           talking about higher temperatures for power uprates,
           and for plants that are 30 years old, maybe we should
           be looking at those sort of things on power uprates,
                       And so forth and so on.  And of fluid
           mechanical components, and degradation of elastomers
           at higher temperatures, and those are the kinds of
           things that maybe if we had a more detailed assessment
           of the impact of power uprates on a checklist, or a
           standard review plan, we might need to look at it.
                       So I had some recommendations which are
           not too dissimilar from looking at margins, and
           looking at licensee event reports, and current
           application review processes, and reevaluation of
           design basis conditions, and uprated conditions, and
           there is essentially no requirements to look at
           synergistic effects.
                       We review based upon current regulatory
           requirements.  Events show indirect evidence of
           potential synergisms, and the agency, I believe, would
           be better served if we had a standard review plan for
           power uprates for BWRs.
                       And G.E. goes a long way to that goal, and
           the NRC needs to do something on acceptance criteria,
           I believe, for the PWRs.  It has been a long time
           since a licensee or a vendor did anything on power
           uprates, and basically we are still dealing with the
           1984 W-CAP report.  And that is basically all I want
           to say.
                       DR. LEITCH:  Gus, your third bullet down
           there says that that standard review plan for power
           uprates is in progress.  These slides are a couple of
           years old.  Is that still true?
                       DR. CRONENBERG:  The standard review plan
           is still an on-the-burner sort of issue that -- well,
           at this point, the agency is not doing a standard
           review plan, and maybe the staff can answer that.
                       CHAIRMAN WALLIS:  Did you have a comment
           on that, Ralph?
                       MR. SWAYBE:  This is Mohammed Swaybe
           again.  No, we are currently pursuing a standard
                       DR. KRESS:  I am intrigued by your bottom
           bullet, and intrigued by the fact that you added QHO
           in parentheses there.  Do you have any ulterior motive
           for that?
                       DR. CRONENBERG:  I just put that in for
           you, Tom.
                       DR. KRESS:  Thank you.  I appreciate that.
                       DR. CRONENBERG:  We don't have any
           requirements for license renewals particularly, but
           anyway something about that.  PRAs can give you --
           well, you know, you believe in PRAs, and it gives you
           some sense of a holistic integrated assessment of what
           things are.
                       We talked about a raw risk aversion LERF,
           and not a risk aversion LERF for a component, but a
           risk aversion LERF for a system, and all these issues
           are before the ACRS.  And some thinking needs to go
           into how we get a better assessment of how systems
           behave as a whole, rather than components, or how the
           plant behaves as a whole.
                       DR. KRESS:  You know, the reason that I
           wanted that QHO over there is you are actually talking
           about power uprates, and you ought to refer back to
           the QHO itself rather than LERF, because what we are
           doing is changing the source term.
                       And LERF is dependent on the source term,
           and of course I think there is enough site dependence
           of things that we really ought to revert back and see
           what we are really doing instead of using LERF.
                       DR. CRONENBERG:  Well, maybe we should
           like at something like a QHO, and the source term is
           changing, but core damage frequency doesn't tell  you
           always the whole story as you know.  It doesn't tell
           you anything about consequences.
                       DR. KRESS:  And I don't think that LERF
           tells you enough of the whole story.
                       DR. LEITCH:  I have heard a couple of
           times today that the G.E. topical reports are to
           perhaps stand in place of the standard review plan. 
           Yet, there are a number of the issues that you talk
           about here as being potential effects that are really
           behind G.E.'s scope of supply; electrical cables, and
           cement control systems, and so forth.
                       So I guess I just don't understand that. 
           Also, I don't understand why the real recommendation
           coming out of Maine Yankee is that there be a standard
           review plan for power outrates, and why aren't we
           doing that.
                       You know, we are looking at a whole bowel
           wave of power uprates here, and what are we going to
           do to them?  Is it on an individual basis, and looking
           at them as though each one is a new case?
                       Isn't there some benefit that could be
           achieved by having a standard review plan, rather than
           considering each one as a separate issue?
                       MR. SWAYBE:  This is Mohammed Swaybe
           again.  I can't speak too much on a standard review
           plan, but I know that was considered and right now we
           are not pursuing a standard review plan.
                       However, as far as future power submittal
           applications, and what we are doing, and the ones that
           are ongoing right now, for the major extended power
           uprate applications, we are considering the Quad
           Cities, Duane Arnold, Dresden, as first of a kind.
                       We are going through those and we will be
           having a public workshop after the completion of
           those.  We are also going to be looking for ways to
           get information out to industry, in terms of how they
           should be submitting these applications, and format,
           and getting the information that we need out to
           industry so that they know what to submit.
                       It is not a standard review plan, but it
           will provide some guidance.
                       CHAIRMAN WALLIS:  What form will it take
                       MR. SWAYBE:  I am not sure at this point. 
           We are considering several options.  It may be a RIS,
           and it may be through workshops, and it may be through
           webpage.  We are not really sure at this point.
                       DR. LEITCH:  It just seems to me that we
           all learned some pretty painful lessons at Maine
           Yankee, and we are kind of flying in the face of that
                       MR. SWAYBE:  I think one of the
           recommendations may have been a standard review plan,
           but there have also been some other lessons learned.
                       And I remember in working in the reactor
           systems branch that there was guidance given down to
           the reviewers, in terms of the kinds of things to look
           for that came out of Maine Yankee.
                       I mean, there was more than just a
           standard review plan recommendation for that. There
           were some letters that came down from management that
           said that this is what we learned from Maine Yankee,
           and be sure that you are looking for this kind of
           information when you do your reviews.
                       DR. LEITCH:  Yes, that is good for those
           specific things, but what I am saying is that the way
           that we improve is by institutionalizing some of this
           experience, and capturing it, and getting smarter as
           we go along; a little bit like we have down in the --
           well, at least I think we have done and are maybe
           continuing to do in the license renewal process.
                       But here it seems like we are starting
           each one kind of with a blank sheet of paper.
                       MR. SWAYBE:  Well, I think on the first
           few that you are probably right.  We do think of them
           as first of a kind, the first few.  You know, 15 or 20
           percent.  But I think after that, that you will see
           that we will provide some guidance and hopefully
           things will be a little more standard.
                       CHAIRMAN WALLIS:  This will be a sort of
           lessons learned from Duane Arnold, Dresden, and Quad
                       MR. SWAYBE:  Okay.
                       CHAIRMAN WALLIS:  Anything else?  If not,
           it is probably better if we take our break now before
           we hear from G.E. so we don't interrupt your
                       Well, I guess we will do your introduction
           first and then we can take our break.  Let's do that.
                       DR. FORD:  Mr. Chairman, I have to say
           that I have a conflict of interest here, being an ex-
           G.E. member, and as I understand the rules of the
           game, I am allowed to comment, but not judge.
                       DR. KRESS:  Only on factual matters and
           not expressing opinions.
                       CHAIRMAN WALLIS:  You can ask questions
           and we can judge the answers.  It would be very useful
           if you would ask the right questions.  So let's
           proceed with the open part of G.E.'s presentation.
                       MR. KLAPPROTH:  Okay.  My name is Jim
           Klapproth, and I am the manager of engineering and
           technology in San Jose, and I would like to thank the
           committee for an opportunity to come and give an
           update from our perspective on power uprate.
                       We have not been in front of this
           committee since 1998, and I think that as we have seen
           here there is a lot that has transpired in the last 2
           to 3 years, especially with the extended power uprate
                       And it is very timely for us to have an
           opportunity to have this discussion.  I have two ot
           her individuals here with me that I would like to
                       Israel Nir is on the far left, and he is
           the power uprate process project manager at G.E., and
           he will be speaking primarily about the constant
           pressure power uprate approach, which I believe the
           committee has had an opportunity to at least look at.
                       And also to my immediate left is Gene
           Eckert.  Gene is the engineering fellow for transients
           and reactor systems control, and he will be speaking
           primarily to a lot of the issues that have come up
           today relative to the special topics and synergistic
                       As an aside, I would like to note that
           this is Gene's 65th birthday today, and I couldn't
           think of a better present than to have him here today.
                       So, anyway, I will run through a quick
           introduction here.  We will have some opening remarks
           and then I will turn it over to Gene to kind of go
           through an introduction and give you a little history.
                       We have heard a lot today about the G.E.
           topical reports.  I want to step through the five
           percent stretch power uprate, and then move to the
           mid-1990s and to the extended power uprate in the 5 to
           20 percent uprate.
                       The third step in our progress has been
           the thermal-power uprate program, or thermal-power
           optimization, which takes advantage of the improved
           water flow on certain need characteristics so we can
           realize a 1-to-1-1/2  percent power uprate.
                       And then finally the constant pressure
           power uprate, which we will focus on.  Then we would
           like to go into closed session and really get into
           more details and specifics about what the impacts of
           power uprate are.
                       And before I turn it over to Gene, just a
           couple of opening remarks, and basically these five
           bullets are the key messages of our presentation. 
           First of all, there has been an extensive amount of
           experience with extended power uprates.
                       And there are five plants, and it says
           four here, but there are four utilities, and actually
           five plants that are currently operating under
           extended power uprate conditions; three domestic and
           two overseas.
                       And in addition, we have completed the
           analysis and it is currently under staff review, of
           power uprate programs for an additional five plants.
                       DR. KRESS:  Who reviewed the overseas
                       MR. KLAPPROTH:  KKL.
                       DR. KRESS:  Was their  review as extensive
           as the ones that our staff does?
                       MR. KLAPPROTH:  I believe so, yes.
                       DR. BOEHNERT:  Were those 20 percent or
           higher uprates?  What was the uprate on those?
                       MR. KLAPPROTH:  I think it was 117.
                       MR. ECKERT:  KKL did a five percent
           somewhere to our original uprates, and then they did
           this additional 14-1/2 percent.  So they are close to
           120.  And the KKM plant is up around 114, above the
                       DR. SCHROCK:  Is that the way that you
           calculated it; that it is based on the percentage of
           the original?
                       MR. ECKERT:  That is the way of keeping it
           in our books for sanity since they are going in
           different steps here, yes.  These are the numbers that
           they give you and they are right around 119.
           something.  They are not above 120 from originally.
                       They were 104.2,. and then 114, or
           something like that.
                       CHAIRMAN WALLIS:  And was that the
           Leibstadt one?
                       MR. ECKERT:  Yes, that was the Leibstadt
           one, the bigger one, yes.  A bigger uprate.
                       MR. KLAPPROTH:  In fact, I think we have
           a chart later in the presentation.
                       MR. ECKERT:  We have information from
           their program.
                       MR. KLAPPROTH:  The second major bullet,
           we have had a lot of discussion today about margins,
           and from our perspective, the safety margins are
                       And both Ralph Caruso, who I think back in
           December when he was in front of this committee, the
           deterministic licensing criteria are maintained for
           power uprate.  There is no request for any relaxation
           of the deterministic licensing criteria.
                       In other words, we believe that all the
           safety margins are maintained.  I think a lot of the
           discussion we have been having previously is relative
           to performance margin, and operating margin, and there
           is a slight impact in some cases on operating margin,
           and we understand that.
                       And relative to safety margins, we believe
           that there is no impact on safety margins for power
           uprates, especially under the constant pressure power
           uprate approach, which is a no pressure increase.
                       And you will see as we go through the
           presentation in the closed session the impact on plant
           systems, and on plant response to events, such as
           design basis accidents, and transients, is fairly
           benign relative to prior pressure increase power
                       So again we believe that the safety
           margins are not impacted for extended power uprates.
           and power uprates.
                       DR. CRONENBERG:  When you say that, what
           about, for example, like the feed water line?  Do you
           view that as a non-safety impact, and design loads,
           and even the operating conditions are higher flow
           rates and higher temperatures on the feed water lines.
                       MR. KLAPPROTH:  We have a specific
           example, and we will discuss that in the closed
           session, but basically our position will be that as
           long as you stay under the 1250 limit, anything
           underneath that is additional margin over and above
           the safety margin.
                       DR. CRONENBERG:  Okay.  So you are
           defining safety margin as anything above the design
                       MR. KLAPPROTH:  Exactly.  And I believe
           that is consistent.  I think if we go back 10 years,
           I believe -- and, Tony, you can help me on this, but
           in the improve tech spec role, I think NEI and others
           took a very close look at what the definition of
           safety limits and safety margins are.
                       And I think there was some guidance put
           together by NEI which was accepted by the staff on
           what the definition of safety margin is relative to
           operating margin.
                       MR. ECKERT:  And all the appropriate code
           equations were checked again for the new operating
           conditions, and any temperature change that took
           place, and the flow changes that took place, and in
           compliance with all the appropriate code equations for
           the piping was done for each small uprate or big one.
                       DR. CRONENBERG:  So when we see something
           in an SAR that says the safety margin is not changed,
           what we are really talking about is that you are below
           the design limit?
                       MR. KLAPPROTH:  Right.
                       CHAIRMAN WALLIS:  Could you say more about
           Bullet 3?
                       MR. KLAPPROTH:  The constant pressure
           power uprate bullet?
                       CHAIRMAN WALLIS:  Yes, without getting
           into something which is proprietary.  It is not just
           constant pressure.  You get your power uprate by
           flattening the power distribution of the core without
           changing to the maximum temperatures and all those
           things which -- well, if you had just taken and raised
           the power everywhere, you would be changing those
                       But you have done some clever engineering
           to keep other things constant other than just
           pressure.  Can you talk about those now or is that
           something that is more proprietary?
                       MR. KLAPPROTH:  I think we would prefer to
           talk about that in the closed session.
                       MR. ECKERT:  Well, on the pressure side,
           we control pressure independent of power.  I mean,
           they interact, but we have a pressure controller that
           keeps the pressure where we want it, and that this
           plan for our uprate, we make sure that when we get to
           the new higher power level that we have the same
           reactor dome pressure that we had before.
                       CHAIRMAN WALLIS:  Well, if we had that, it
           would just draw out more water at the same pressure.
                       MR. ECKERT:  Basically, yes.  And we have
           a control system that will hold it where we want it.
                       CHAIRMAN WALLIS:  And you achieve that by
           not -- without raising this sort of maximum fuel
           temperatures and things like that.  So there must be
           some engineering done to distribute the load more
           evenly across the core.
                       MR. KLAPPROTH:  Well, we will talk about
                       DR. KRESS:  When you say constant
           pressure, you are talking about the pressure in the
           dome or --
                       MR. ECKERT:  The reactor dome pressure,
                       DR. KRESS:  Which means that you are
           blowing more steam, and so the resistance between
           there and the turbine has to be less?
                       MR. ECKERT:  Well, it is built already. 
           The resistance is there, and so at the turbine, we
           actually drop pressure a little bit at the higher flow
                       CHAIRMAN WALLIS:  So you need an even
           bigger flow rate to get the power uprate?
                       MR. ECKERT:  We have to build the turbine,
           and the MODs get a little tougher by holding this
           pressure philosophy.  But inside in the primary part
           of our system, and the whole pressure boundary, it
           becomes much simpler, and that is what we will talk
                       DR. KRESS:  Okay.  We will wait until
                       MR. KLAPPROTH:  And in general, for
           example, on the LOCA analysis, we will show that the
           power uprate, really the effects of LOCA, the effect
           of power uprate is very minimal on LOCA analysis.
                       CHAIRMAN WALLIS:  And you still have the
           vessel at the same pressure and so you make a hole in
                       MR. ECKERT:  It is the same sized pipes.
                       CHAIRMAN WALLIS:  And that sort of
           overview needs to come forward so that someone who is
           looking in from the outside can understand how you
           achieve it without it being too proprietary.
                       MR. KLAPPROTH:  Okay.  The fourth bullet,
           the high volume EPU review request anticipated.  There
           was a question this morning on how many do we
           anticipate over the next year or so.
                       Right now the staff has Dresden and Quad
           Cities, and Duane Arnold reviews in progress.  We
           anticipate between now and the middle of next year
           that there will be another five plants submitting for
           power uprate, and extended power uprate applications,
           using the constant pressure power uprate approach.
                       And beyond that our projections are over
           the next several years that we would expect at least
           another four plants per year coming to the staff. 
           That's why we think it is appropriate to move to a
           streamline approach, which is again linked to our
           constant pressure power uprate.
                       And actually we will be meeting with the
           staff tomorrow and getting the initial feedback on the
           topical report that I believe the staff has seen on
           our constant pressure power uprate, and hoping that we
           would have a safety evaluation issue by the end of the
                       DR. KRESS:  Do you think we have reached
           the limit of power uprates, or is there a potential
           another round?  How far can we go?  I know that there
           are different things that limit --
                       DR. SCHROCK:  Isn't it limited by your
           radial peaking?  I mean, all you are doing is taking
           advantage of the fact that the older plants are more
           peaked, and now you are flattening it.
                       But there is a limit to what you can get
           if you spread it uniformly --
                       MR. KLAPPROTH:  Well, at this point, we
           are really where we want to go at this point, which is
           20 percent.  We have not really looked beyond 20
           percent in the NSSS environment to say what is the
           next limit.
                       Ralph mentioned this morning a limit. 
           However, that is based on current licensing analysis,
           and I think we have moved to more realistically track
           the analysis, and we will find that we have some
           additional margin that may allow us to go higher.
                       There may be some related issues that we
           need to worry about when we go above 20 percent, but
           we frankly have not done a study to say, well, we can
           go to 129, or we can go to 142.
                       DR. KRESS:  That is something that we
           don't need to worry about right now.  We are not faced
           with that.
                       MR. KLAPPROTH:  So, with that, I will turn
           it over to Gene to walk through some of the background
           information if there is no further questions.
                       CHAIRMAN WALLIS:  I think it will be
           interesting.  Maybe it is not G.E.'s job to look at
           one of these things and say with a pressure vessel,
           and core geometry, what do you do to get more power
           out of it, and presumably we circulate more water and
           things like that.
                       And maybe you are not asking for it and so
           you don't want to get into the details, but it is kind
           of interesting for some HD student or someone to look
           at one of these things and say, well, here are all the
           things that we could do.
                       We could get a hundred percent more power
           out or what, and I would be interested to see that. 
           Please go ahead.
                       MR. ECKERT:  And we may be asked to answer
           that question as good engineers by our managers.  This
           is a brief run through, and we have been with you
           before, and especially connected with the extended
           power uprate power program, and it is one of those
           generic topical reports that were put together back in
           June of '98.
                       We had some follow-up meetings with you in
           July, answering some questions that you asked.  It was
           built off to 5 percent in an earlier program, and
           keeping as Jim was saying the criteria for
           acceptability of the plant was to be kept the same,
           and that we were not changing the criteria that we had
           to meet.
                       We expected this to be handled pretty
           well, and it has been holding up pretty good, and we
           can see that we are getting close to some things, and
           that's probably it is not an automatic answer that we
           go beyond 20 without some changes in the NSSS.
                       The balance of the plant did need
           significant changes, and we recognize that, and the
           utilities struggle with what is it worth, and is it
           worth that investment at our plant, and many of them
           are deciding, yes, it is.
                       I have this bullet about MELLLA.  We are
           throwing acronyms out here.  This is a term that G.E.
           has used over the years to describe the operating
           domain that we use on our map.
                       We call it a power versus core flow map,
           and we have defined the range of operability at which
           we call normal operation, and it has expanded over the
           years up to this title called, "Maximum Extended Load
           Line Limit Analysis."
                       Load line meaning the rod line, flow line,
           and that if we change core flow power, it moves up and
           down with core flow, and that is a common way we
           change power in the plants.
                       We don't change our rod patterns up at
           high power generally. We change core flow to do that,
           and we will see some pictures of it in the rest of the
                       CHAIRMAN WALLIS:  Are you going to show us
           the stability and instability region?
                       MR. ECKERT:  We will talk about which
           region is most at risk for stability considerations
           and what happens there.  When we went to extended
           uprate, we constrained ourselves in the utilities not
           to go above the previously licensed boundary, and that
           was an important term relative to the stability
           question, because we did not want to push ourselves at
           that time, or now, beyond that line for these basic
           extended upright plants.
                       And so there may be some plants that were
           not licensed all the way to this line before, but the
           fleet had examples of every product line that had gone
           up to this boundary, and so some plants are moving up
           to the previously licensed boundary, but none of them
           -- and what we are calling the extended power uprate
           program -- are going beyond this previously licensed
           boundary on the power flow map.
                       And you can think about it as a power flow
           ratio kind of boundary that we have agreed to remain
           constrained within.  There is a combination of things
           that came out of this effort, which is partly generic,
           and partly plant specific.
                       And that was differentiated and defined as
           we went into our topical reports that tried to
           establish the guideline that this is needed to be done
           plant by plant because it has some unique features.
                       And that these are things that need to be
           done even cycle by cycle, which is pretty costly
           coupled to our GESTR effort for reloads, and there
           were some things that we could handle generically and
           say that all BWR4s are bounded by this one analysis,
           or all BWR6s can be bounded by this one analysis.  And
           wherever possible that was included in our generic
                       CHAIRMAN WALLIS:  So this mellow boundary
           is independent of the fuel or the flux distribution?
                       MR. ECKERT:  It is applicable to all of
           our fuel types, and plants operate up to that
           boundary, and we will look at it in detail.
                       CHAIRMAN WALLIS:  And the boundary is
           somehow independent of fuel and so forth?
                       DR. KRESS:  When you decrease flow, if you
           had the same power, you would increase the void
                       MR. ECKERT:  Correct, which unbalances the
                       DR. KRESS:  And so the reactivity comes
                       MR. ECKERT:  It pushes you back down.
                       DR. KRESS:  And this MELLLA line is the
           description of that effect?
                       MR. ECKERT:  And it is almost -- you know,
           for the first rule of thumb, it is a constant void
           fraction line.  It is not perfect, but it is basically
           that the reactor forces us to stay at the said void
           fraction when we have the same rock pattern.
                       DR. KRESS:  So it is a natural --
                       MR. ECKERT:  It is a basic physical 
                       DR. KRESS:  --  physical characteristic of
           all the reactors?
                       MR. ECKERT:  Of our wonderful machine,
                       DR. KRESS:  I think that is useful for
           this committee to understand.
                       MR. ECKERT:  We will have more detail
           later, Tom.
                       DR. KRESS:  So it would depend on your
           fuel in some way wouldn't it?
                       DR. KRESS:  Well, it really does depend
           some on that, yes.
                       MR. ECKERT:  We calculated for different
           fuels, and it is amazing how close it follows, because
           it has got the thermal-dynamics of the constant void
           fraction built into this.
                       DR. KRESS:  It is really the effect of
           void fraction on the neutrons, and it is almost
           independent of the kind of fuel it is.  Not quite, but
                       MR. ECKERT:  All of our fuels have strong
           negative void reactivity characteristics, and so it
           forces us back to very close to identical void
           fraction, which is --
                       CHAIRMAN WALLIS:  Which shuts itself down,
           and moves it around.
                       MR. ECKERT:  We submitted two different
           topicals basically.  One we call ELTR1, and that had
           followed our previous generic document LTR1, which was
           the 5 percent uprate, and this is the bigger uprate,
           but it was basically a guideline document.
                       Here is the scope of what needs to be
           looked at and here are the key criteria that we are
           going to commit ourselves to.  We reviewed that with
           the staff, and we reviewed it with you, and we reached
           agreement on that.
                       And then ELTR2 is the place where we have
           documented generic topical material that can be used
           by different plans, and as generic, we think that this
           issue can be settled this way, and a plant simply has
           to confirm that we are within the generic package that
           you have submitted before.
                       For the big uprates, obviously there were
           a few less generic things that we could do than we did
           for the smaller uprates, but we still had this
           advantage to the total program.
                       We presented this and reviewed it with
           you, and coupled very closely with the Monticello
           extended uprate.  So it was a BWR3 and then it went up
           6.3 percent above what they had started operating
           their unit at.
                       And then very closely coupled after that
           were the Hatch 1 and 2 submittals that followed this
           program.  And we had questions from you, and tried  to
           and did resolve that, and have received acceptance of
           that program.  And that has led to all the activity by
           the utilities.
                       CHAIRMAN WALLIS:  And this concluded --
           you are saying that ACRS concluded or you concluded?
                       MR. ECKERT:  Well, mutually we concluded
           it, and we are moving ahead.
                       DR. KRESS:  We actually had a letter on
                       MR. ECKERT:  The staff has given us
                       CHAIRMAN WALLIS:  Well, we certainly
           approved it, and so I was wondering if we used these
           exact words?
                       MR. ECKERT:  I think these are my words. 
           And I am not too much of a salesman, but I have a
           little.  There is some terminology that we wanted to 
           make sure that you understood, and we have probably
           since then, by using the term stretch power uprate a
           little more than we did back then.
                       And that meant this early program that was
           up to about 5 percent uprate, and it was basically
           already built into most FSARs, and it was just that we
           were not licensed there immediately, and we just went
           up to it.
                       And it is based on percent of original
           licensed in most of our discussions.  Extended means
           the step that could up to the 20 percent level above
           the original license.
                       All plants are not choosing to go that far
           based on what their economics are for their turbine
           generators, or whatever their system might be.  It
           might be that they don't have room for another pump to
           go in, or would need it, or whatever.
                       So economically each customer will look at
           that, and pick a point to shoot for.  And just
           recently you are seeing the ones that are coming close
           to saying, hey, we think we can get darn close to 120.
                       DR. LEITCH:  Gene, just a terminology
           question here.  If I say the term extended power
           uprate, that generally means that there is an increase
           in pressure; and if I say the term constant pressure
           power uprate, I understand what that means.
                       MR. ECKERT:  That's a good question.  In
           the past, our EPU program included the potential to go
           up in power and pressure, depending on the balance of
           design trade-off's that would go on.
                       And by going up in pressure, we could save
           a little bit in our turbine MODs and things like that. 
           So the general program in 1998 had the option of
           pressure increases, as well as power increases, and
           you will see those topicals discussed it.
                       The CPPU, constant pressure power uprate,
           fresh stuff coming at you now, is to constrain
           ourselves to keep that dome pressure constant, even
           though we may be going up as much 120 in power.
                       And that is the more recent path, and even
           the ones that have done power uprates we will talk
           about in a little bit.  Many of them, if they have
           gone up in pressure, they haven't gone very far, and
           then they decided to do most of their uprates without
           raising pressure because of saving lots and lots of
           extra considerations for the primary boundary.
                       CHAIRMAN WALLIS:  Do you have figures for
           the cost per installed whatever, megawatt or whatever,
           whatever the capital cost is for this uprate?  I mean,
           you are not buying a new reactor.  You are just buying
           some balance of power.
                       MR. ECKERT:  You are asking the wrong guy.
                       CHAIRMAN WALLIS:  Well, that is the motive
           for this isn't it?
                       MR. ECKERT:  Yes, it helps.  It helps. 
           Some of it is avoiding just calculational costs, and
           lots of paper, but there could well be some real hard
           work changes, too, for the pressure change.
                       And that is these extra bullets here, the
           different phases of uprate that have been coming at
           you.  There is one that we call thermal power
           optimalization, and you may know it better just as an
           Appendix K uprate.
                       In the sense where the better feedwater
           measurement and equipment could get another 1 or 1-1/2
           percent power by sneaking up closer to the analysis
           that was done traditionally at 102 of the rated power.
                       And we have a parallel program for the
           BWRs, and the staff has received a generic topical
           that tried to scope out what was involved in doing
           that type of uprate.  That is not our main discussion
           here today, but we wanted you to know that was also
           coming along.
                       DR. BOEHNERT:  Does that mean that someone
           can go to 121.4 or 5?
                       MR. ECKERT:  Well, that is a good
           question, and we haven't really faced it.  In theory,
           the answer would be yes, but in practice, most of us
           are being pretty cautious about saying that.
                       In reality, it says that if my license is
           here, and my safety analysis is here, can I creep
           closer to it because I have less power uncertainty,
           and in theory the answer is yes.
                       I already have it basically.  I do a 120,
           and it says that I am going analysis at 123-1/2
           already.  So I would vote yes, but I have more
           cautious people behind me.
                       And we are not forcing you to say, yes,
           you can go beyond 120 that way.  Some day somebody may
           come and ask for that.
                       DR. BOEHNERT:  So you have not made a
           decision one way or the other, I guess?
                       MR. ECKERT:  The topical that we have
           submitted says that if a plant is already upgraded
           five percent or whatever, they can abide this thing. 
           So in theory if somebody had really gone all the way
           to 120, we would say it is theoretically possible.
           We don't have a project pushing for that at this
                       DR. BOEHNERT:  Okay.  Thank you.
                       MR. NIR:  We recommend that the customer
           will analyze and perform the analysis at 122, or 2
           percent above 120.
                       MR. ECKERT:  All of the new ones are being
           done under the old rules with respect to power
           uncertainty, and none of the new submittals to you or
           the staff at this point are saying we are going to an
           uprate, and we are only doing it with this tiny
           uncertainty factor.
                       And in the constant pressure one, we will
           talk about more during the presentation, and we have
           already touched on that; that it just involves being
           constrained, and constraining ourselves that dome
           pressure does not go up with the power, which we can
                       That is our common control system for all
           our plants, and it is constrained by our tex specs. 
           We will talk a little bit about on-line
           implementation, which is something that maybe wasn't
           as actively on our table with you when we were here in
                       And that we have now come up with some of
           the better ways to implement uprate as we go through
           the licensing approval process, as well as the
           practical parts of doing plant MODs, and so forth.
                       CHAIRMAN WALLIS:  You don't just suddenly
           throw a switch and the power is 20 percent bigger?
                       MR. ECKERT:  Right.  These give you more
           details about these different parts of the program,
           and what was called the stretch, and the five percent
           one, and it introduced this idea of LTR1, and LTR2.
                       And there was good communication between
           us and the staff, and I thought a good exchange, and
           a good challenge to each other.  The standard was
           similar and built on it, and here are some dates at
           which these things were submitted, and when our
           plants, the lead plants for this program made their
                       I think Fermi-2 was the lead plant at the
           five percent part of it, and Monticello and Hatch were
           the lead plants on the larger ones, even though they
           didn't go all the way to 20 percent.
                       On the so-called TPO or the small uprate,
           this gives you a few details on the way that we were
           doing this, and we are in the process of reviewing. 
           We have received some RAIs from the staff and are
           responding to them and moving toward approval of this
           half we hope.
                       I think there will be some plants that
           follow this lead, or a couple that are submitting such
           submittals to you independent of our topical approach,
           and in some manner this will be merged together as the
           staff reviews the process.
                       Basically, we are trying to take advantage
           of everything that was already done at the 102 or more
           above today's license, and to identify pretty clearly
           what ought to be reviewed because it was done back at
           a hundred percent.
                       Things like ATWS were agreed upon to be
           done back at a hundred, for example, and so we talk
           about what happens if we were up a percent or a
           percent-and-a-half above that.
                       MR. KLAPPROTH:  I think the only other
           point that we should make here is that last bullet. 
           We do expect three submittals by the first quarter of
           next year on a TPO approach.
                       CHAIRMAN WALLIS:  And that involves some
           different instrumentation then?
                       MR. KLAPPROTH:  Better instrumentation and
           measuring feed water flow, which is a primary element
           in our power uncertainty calculation.
                       CHAIRMAN WALLIS:  And is there certain
           technology being used for that flow rate, flow
                       MR. ECKERT:  The technology has been
           reviewed by the staff and has gone through the ringer. 
           Caldon is one of the suppliers, and I think ABB has a
                       CHAIRMAN WALLIS:  So anyone who can prove
           itself is?
                       MR. ECKERT:  Yes, and we are saying that
           based on whatever they claim, you can creep ahead
           following this guideline of scope of work.
                       DR. UHRIG:  This is with the original
           single pass system from Caldon, and the newest X
                       MR. ECKERT:  We have written our work that
           says that we are not claiming what the improvement is. 
           We have said that if you can defend a claim of a
           percent improvement, here is the safety work that
           would be needed.
                       The CPPU you will hear us talk about quite
           a bit today, and we hope that it facilitates the
           future applications.  It takes a lot of work out of
           the process because we aren't pushing temperatures and
           pressures harder in lots of the equipment.
                       It remains functioning at the same
           pressure temperature conditions that it is operating
           at today.  It gives us another vehicle to work with,
           and our utilities to accomplish the uprates without
           extra work involved that the pressure change would
                       We have submitted this topical generic
           approach to this earlier this year, and so we are in
           the process of that review.  Tomorrow is a meeting to
           discuss this, and keep communicating about what needs
           to be done to reach agreement on what should be
           included in this approach.  We will hear more later
           and it involves some other recommended improvements
           just in the process of going through the uprate
                       This little chart talks about the on-line
           implementation IDF, which is trying to decouple the
           moment we actually have approval on an SER from the
           staff, and to say, yes, we agree, and you can go up in
                       And from when outages are for a given
           plant, and so the outages give the utility the time to
           do any MODs that are needed, and they will do that in
           a series of changes maybe for larger uprates.
                       But they would introduce some MODs and an
           outage in anticipation of getting approval during the
           cycle, and having submitted it to the staff for review
           and resolving questions, and getting approval mid-
                       They are prepared to at least take
           advantage of part of that approved new power level
           during this first cycle that the approval is received.
                       The approval doesn't have to come
           immediately at the time of a start up from an outage,
           and that helped quite a few ways.  There are some
           things that you have to wait to get changed out here
                       But part of the uprate can be taken
           advantage of right away, and it helps in the
           scheduling of all this stuff with utilities and
           ourselves, and with the staff.
                       It takes a little bit of heat off the
           staff, and they don't have to be right there on the
           day they want to pull rods and come out of an outage. 
           And so it made it more practical for all of us.
                       This chart -- we keep showing you these
           with the list of plants, and the list keeps growing. 
           The column on the left are the plants that have
           basically done uprates in the past and have included
           some pressure increase in their plant.
                       And part of our discussion with you today
           is especially aimed at helping you understand the
           constant pressure path that we think that everybody
           else will be on.
                       Some of the plants on this column even
           might have uprated or had increased pressure during
           part of their uprate, but not all of it.  Like this
           plant in Switzerland, the Liebstadt plant, when they
           did their first 5 percent uprate, they did the uprate
           and pressure as well, and it was 20 pounds or
           something.  It was some amount.
                       But then when they went to the big uprate
           that followed, they adopted our constant pressure
           thing just for practical reasons of their own.  So
           they have gone the last 15 percent or 14 percent
           without raising pressure.
                       But they did some analysis with the
           pressure increase, and they looked back and said, hey,
           I would rather try to do it without all those set
           point changes, and all the other changes that are
           needed, and they also have gone a long ways without it
           for the second half of their uprate.
                       It is a pretty big list over here of
           plants that have already or are planning to go up in
           power using the constant pressure approach.  And the
           starred ones are the ones still in process, and
           including the ones that we talked about before.
                       And Cofrentes is a plant in Spain that has
           done a small amount of uprate and are going to bigger
           uprates in the process of that.  We show the Brown's
           Ferry units on here that weren't on the previous list,
           but we have been working with them and aiming at a
           target up here, and they are present in the crowd here
                       And they are very interested in seeing the
           same program, and there are others that we are talking
           to.  The last chart there is the real benefit for all
           this that we are all seeing as an industry, and we are
           trying to accomplish wisely and safely.
                       There are pretty big numbers starting to
           add up here.  Completed uprates in the neighborhood of
           1,250 megawatts.  There is some differentiation in the
           charts here.  The first block are the five percent
           uprates, and then there is the little chunk on top of
           here that are the EPUs, the bigger uprate programs
           starting to be shown on the map.
                       CHAIRMAN WALLIS:  I don't understand that. 
           Are you referring to total megawatts of?
                       MR. ECKERT:  This is the added megawatts
           to the fleet.  It is not an individual plant, but this
           is the sum of the plants that have uprated.  And these
           are the ones in process, and these are almost totally
           the extended uprate plants that are part of our plan.
                       We are estimating from the year 2001 to
           2003 that we will get these additional uprates and a
           little bit coming in as part of what we are calling
           thermal power optimization.  Not as big, but still
           vital power for these people.
                       DR. KRESS:  Now, going from the second
           column to the third column, does the third column
           include the bottom of the second column that are in
                       MR. ECKERT:  No.  These are contracts in
           hand, and --
                       DR. KRESS:  They are expected to be
           finished before you get to this other?
                       MR. ECKERT:  Yes.  And this would be even
           our estimate out further.
                       DR. KRESS:  So those are all new
                       MR. ECKERT:  Yes, each column is
                       DR. CRONENBERG:  And is Brown's Ferry in
           the forecast?
                       MR. NIR:  I believe it is in the third
           column, 2001.
                       MR. ECKERT:  Yes, at the time that this
           chart was made.
                       CHAIRMAN WALLIS:  And that is equivalent
           to five new plants?
                       MR. ECKERT:  Five, 930 megawatt plants.
                       CHAIRMAN WALLIS:  And the problem is that
           the 930 is so close to the 960 and the 1100, do you
           think that you are talking about individual outrates?
                       MR. ECKERT:  Yes, that is what is sounds
           like, but it was just a way of expressing it.  We
           believe that we are consistent in supporting what the
           staff requirements are in terms of supporting the
           plants for additional power.
                       CHAIRMAN WALLIS:  And this is your
           contribution to the 10,000 --
                       MR. ECKERT:  We just need some longer
           extension cords to reach California though, and we
           can't avoid the fact that this is giving high volume
           work here through the process to the staff, and as
           well for us, and for the utilities, too.
                       CHAIRMAN WALLIS:  Are we through with the
           open session?
                       MR. KLAPPROTH:  That is the end of the 
           session, yes.
                       CHAIRMAN WALLIS:  So let's take a break
           and I think we can come back at five after, and that
           will give us a 12 minute break.
                       (Whereupon, the Open Meeting was recessed
           at 2:54 p.m. and the proceedings resumed in Closed
           Session at 3:05 p.m.)

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