Joint Meeting of the Subcommittees on Materials and Metallurgy, Thermal-Hydraulic Phenomena, and Reliability and Probabilistic Risk Assessment - March 16, 2001

                Official Transcript of Proceedings


Title:                         Advisory Committee on Reactor Safeguards
                               Joint Meeting of the Subcommittees on
                               Materials and Metallurgy, Thermal-Hydraulic
                               Phenomena, and Reliability and Probabilistic
                               Risk Assessment

Docket Number:  (not applicable)

Location:                 Rockville, Maryland

Date:                     Friday, March 16, 2001

Work Order No.: NRC-110                               Pages 1-239

                   NEAL R. GROSS AND CO., INC.
                 Court Reporters and Transcribers
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                          UNITED STATES OF AMERICA
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                                 + + + + +
                                 + + + + +
                              MARCH 16, 2001
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                            ROCKVILLE, MARYLAND
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                       The Subcommittee met at the Nuclear
           Regulatory Commission, Two White Flint North, Room
           T-2B3, 11545 Rockville Pike, at 8:30 a.m., William J.
           Shack, Chairman of the Materials and Metallurgy
           Subcommittee, presiding.
                 WILLIAM J. SHACK, Chairman, Materials and
                   Metallurgy Subcommittee
           COMMITTEE MEMBERS: (cont'd)
                 GRAHAM B. WALLIS, Chairman, Thermal-Hydraulic
                   Phenomena Subcommittee
                 GEORGE APOSTOLAKIS, Chairman, Reliability and
                   Probability Risk Assessment Subcommittee
                 MARIO V. BONACA, Member
                 THOMAS S. KRESS, Member
                 JOHN D. SIEBER, Member
                         AGENDA ITEM                       PAGE
           Introduction . . . . . . . . . . . . . . . . . . . 4
           NRC Safety Research Program. . . . . . . . . . . . 5
           Industry Presentation. . . . . . . . . . . . . . .69
           NRC Staff Presentation . . . . . . . . . . . . . 155
           ACRS General Discussion and Adjournment. . . . . 220
                                                    (8:29 a.m.)
                       CHAIRMAN SHACK:  The meeting will now come
           to order.
                       This is a joint meeting of the Advisory
           Committee on Reactor Safeguards, Subcommittees on
           Materials and Metallurgy, Thermal-Hydraulic Phenomena,
           and Reliability and Probabilistic Risk Assessment.
                       I am William Shack, Chairman of the
           Subcommittee on Materials and Metallurgy.  Graham
           Wallis is Chairman of the Subcommittee on Thermal-
           Hydraulic Phenomena.  And George Apostolakis is
           Chairman of the Subcommittee on Reliability and PRA.
                       Subcommittee members in attendance are
           Mario Bonaca, Thomas Kress, and Jack Sieber.
                       The purpose of this meeting is to discuss
           the status of risk-informed revisions to the technical
           requirements of 10 CFR 50.46 for emergency core
           cooling systems.  The subcommittees will also discuss
           the proposed final report on the NRC Safety Research
           Program.  The subcommittees will gather information,
           analyze relevant issues and facts, and formulate
           proposed positions and actions, as appropriate, for
           deliberation by the full committee.
                       Michael T. Markley is the cognizant ACRS
           staff engineer for this meeting.
                       The rules for participation in today's
           meeting have been announced as part of the notice of
           this meeting previously published in the Federal
           Register on March 1, 2001, and later amended to
           provide for discussion of the report on the NRC Safety
           Research Program.
                       A transcript of the 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 they can be readily heard.  
                       We have received no written comments or
           requests for time to make oral statements from members
           of the public regarding today's meeting.
                       For those who came to attend the 50.46, we
           will be taking about an hour.  That will -- we'll
           start the discussion of 50.46 at about 9:35.  
                       At the moment, I'll turn it over to George
           Apostolakis to discuss the Safety Research Report.
                       MEMBER APOSTOLAKIS:  Thank you, Bill.
                       As the members know, we have a new version
           of the report to the NRC on the Reactor Safety
           Research Program, and we would like to discuss some of
           the outstanding issues today and possibly vote on it.
                       So, Dr. Kress, would you lead us, please,
           through this?
                       MEMBER KRESS:  Yes.  Members should have
           a handout, the new draft version, which fortunately
           now has page numbers on it.  And there are a number of
           items of disagreement or contention, and what I'm
           proposing we do is you have a sheet -- I think you
           should have a sheet that looks like this.  These are
           the page numbers where those items are.
                       There's only really a few of them, but
           some of them are more contentious than others.  And my
           proposal is that we take up the two most contentious
           ones first, and see if we can discuss it and come to
           some sort of agreement.  That would be pages 11, 12,
           13, and 15.
                       MEMBER APOSTOLAKIS:  Okay.  So you are
           skipping the others?
                       MEMBER KRESS:  Well, not yet.  But we'll
           come back to them.
                       MEMBER APOSTOLAKIS:  Oh, okay.
                       MEMBER KRESS:  I just want to start with
           these --
                       MEMBER APOSTOLAKIS:  All right.
                       MEMBER KRESS:  -- because I think the
           others are probably relatively easy.
                       MEMBER APOSTOLAKIS:  Okay.  So you're
           saying 11?
                       MEMBER KRESS:  Pages 11, 12, 13, and shut
           down --
                       MEMBER APOSTOLAKIS:  Okay.
                       CHAIRMAN SHACK:  This whole thing?  We
           have two versions.
                       MEMBER APOSTOLAKIS:  It is an alternate to
           what.  To the previous paragraph?  The one on page 10?
                       MR. EL-ZEFTAWY:  The one on 12 was a
           recommendation to scratch the whole section of the
           standard for PRA.
                       MEMBER APOSTOLAKIS:  Oh, oh, wait a
           minute.  Wait a minute.  So up to page 10, line 198,
           there is nothing, there is no change.
                       MR. EL-ZEFTAWY:  Right.
                       MEMBER APOSTOLAKIS:  So then you have one
           paragraph versus the standard for the PRA.
                       MR. EL-ZEFTAWY:  Right.  The one that's
           starting in -- on page 11, that's a new paragraph.
                       MEMBER APOSTOLAKIS:  So line 199, line
           220, those would be the alternatives.
                       MR. EL-ZEFTAWY:  Right.  And then you have
           to decide if you're going to scratch from 220 all the
           way to 236.
                       MEMBER APOSTOLAKIS:  Yes, and adopt 199
           through 218.
                       MR. EL-ZEFTAWY:  Correct.
                       MEMBER KRESS:  That's the issue.
                       MEMBER APOSTOLAKIS:  Okay.  Okay.
                       MEMBER KRESS:  Now, should we let members
           have time to read both of these first and then discuss
                       MEMBER WALLIS:  Well, what's that page? 
           It seems to be the one from --
                       MEMBER KRESS:  That's the problem.  The
           alternate has a much different thought process and
           much different than the other one.
                       CHAIRMAN SHACK:  Well, actually, what I
           proposed for the alternate was it would replace the
           lines from 184, starting on the risk management tools
           used by industry, through 198, so it's --
                       MEMBER APOSTOLAKIS:  See, that's what I
                       CHAIRMAN SHACK:  It's an alternate that
           replaces a fair chunk of that paragraph, rather than
           an addition.
                       MEMBER KRESS:  So that replaces 184
           through 198.
                       MEMBER WALLIS:  Well, that makes some
           sense but that really changed the subject.
                       MEMBER APOSTOLAKIS:  Yes.  I thought the
           issue of standards for PRAs is an entirely different
                       CHAIRMAN SHACK:  That's a different --
           yes, it just happens to come together here, but --
                       MEMBER APOSTOLAKIS:  Oh, okay.  So the
           alternate, then, in our report would replace the risk
           management tools.  Because I thought when I saw the e-
           mail that this was really a rephrasing of that --
                       CHAIRMAN SHACK:  Right.  It's a rephrasing
           of the 184 to 198 section.
                       MEMBER APOSTOLAKIS:  Well, I'm for the
                       CHAIRMAN SHACK:  I would also just suggest
           that from reading last night the 177/179, I would take
           out the "It can be argued that licensees are
           adequately managing risk during planned outages."  And
           just go directly to "The nuclear industry has made
           substantial efforts."
                       MEMBER APOSTOLAKIS:  Wait a minute.
                       MEMBER KRESS:  I think I would support
                       MEMBER APOSTOLAKIS:  Where is that?
                       CHAIRMAN SHACK:  It's on 177.
                       MEMBER KRESS:  Now, let me tell you --
                       MEMBER APOSTOLAKIS:  And then you would go
           directly to where?
                       CHAIRMAN SHACK:  I would take that
           sentence out and then take off the introductory
           phrase, "It is certainly true that," and just say,
           "The nuclear industry has made substantial" --
                       MEMBER KRESS:  And start there.  But let
           me -- now, I was against this change.
                       CHAIRMAN SHACK:  Completely.
                       MEMBER KRESS:  Completely.  That was the
           word.  And let me tell you why.  The major message in
           these lines 184 down can be found in lines 184 and 185
           and 186 and part of 187.  And that major message has
           been done away with, and that's a message I think
           needs to be said because it -- to me, it is the -- it
           highlights the major difference between what the
           industry does and needs and what the regulatory agency
           does and needs.
                       So I didn't want to lose that message,
           which the alternate -- the alternate proposal loses
                       CHAIRMAN SHACK:  Deliberately.
                       MEMBER KRESS:  Deliberately, of course.
                       MEMBER WALLIS:  Why did you want to lose
                       CHAIRMAN SHACK:  Because I personally
           think that, you know, we've made that argument in our
           '99 letter, that there was this distinction between
           what the NRC was interested in and what the licensee
           was interested in.  I think that's a false
           distinction.  You know, if we're out here to just --
           to computer this number, I don't think that's
                       MEMBER KRESS:  It's not a false
           distinction, because there are two reasons for having
           shutdown risk assessments.  One of them is to manage
           that shutdown risk, as it is ongoing, and that -- the
           tools for that are what the industry uses and they're
           good tools.  NRC needs to know about those tools and
           needs to be able to do that also.
                       But that doesn't help them at all when
           they go to risk-inform the regulations.  Those tools
           tell them nothing.  It just gives them a little -- a
           few insights.  This tells them nothing about the risk
           contribution of shutdown.  That's the problem.
                       And if you want the risk contribution due
           to shutdown to factor in to your risk-informing the
           regulations, you have to have this difference.  And
           it's a different animal.  It's not easy to do.  And
           that's the reason it hasn't been done; it's not easy. 
           And that's why some research is needed.
                       But that's my whole problem.  If you want
           to risk-inform the regulations, you have to have this
           component in there.  And that's my problem.
                       CHAIRMAN SHACK:  I mean, I will argue that
           the reason I want to do shutdown risk studies is I
           want to be able to make the statement that we made
           that there are unlikely to be any major contributors
           to risk that have not been identified that we can make
           about normal operations.  I don't think we can make
           that statement about shutdown risk.  I don't think we
           can make it about fire risk.
                       MEMBER KRESS:  I don't mind making that
           statement also.  I just don't want to lose this
           distinction, though, because to me it's the major
           distinction.  I wouldn't mind adding --
                       CHAIRMAN SHACK:  Being the major one is,
           in fact, that you want the assurance that you've
           identified to measure the contributors to this.
                       MEMBER KRESS:  Well, I think this is
           equally important.  I think they have equal
                       CHAIRMAN SHACK:  That's why we completely
                       MEMBER WALLIS:  I don't understand really
           why there's so much disagreement.  Can't you retain
           the sentence -- two sentences that Tom would like to
           retain?  Is there something offensive about them?
                       CHAIRMAN SHACK:  What's offensive about
           it, of course, is it was stuffed the last time we sent
           it up.
                       MEMBER KRESS:  Well, you know, that
           shouldn't be any reason why we -- we shouldn't give
           good advice.
                       CHAIRMAN SHACK:  I think it puts the wrong
           emphasis on why you're doing it.
                       MEMBER APOSTOLAKIS:  I don't see the two
           points of view being very different, and I don't see
           why you would have to say which one is more important
           than the other, although I tend to agree with Bill. 
           I think, you know, if there is a question of not
           knowing of some vulnerability, that is really the most
           important thing you would like to know about it.
                       But why do we have to say what's more
                       MEMBER KRESS:  Well, I don't think you
           have to.  I would be in favor of keeping both
           sentences.  I just don't want to lose this thought.
                       MEMBER WALLIS:  I think you could keep one
           of these, you can just take it on the end of that
           section.  It's not incompatible, is it?
                       MEMBER KRESS:  That would suit me.
                       MEMBER APOSTOLAKIS:  Okay.  So somebody
           will do that?
                       MEMBER WALLIS:  Tom will do that.  Tom has
           dictatorial authority.
                       MEMBER APOSTOLAKIS:  Editorial or
                       MEMBER WALLIS:  It's one of those Latin
           terms that you would have to -- the concept is
           probably unknown in --
                       MEMBER KRESS:  Okay.  Now, that sort of
           gets us on the road for maybe resolving that one.  The
           next one is this section on -- starting on line 219. 
           And I think the proposal there was to just zap that
           section all together.  That's the question.  Do we
           want to zap that section?
                       MEMBER APOSTOLAKIS:  Well, since I
           proposed that, it's not that I'm against the agency
           spending resources to support the development of
           standards for PRA.  It's just that I thought that this
           is something that the agency has committed to do. 
           It's something that they will do.  And I don't view
           that as research.  So I didn't think it belonged
           there, but I didn't really --
                       CHAIRMAN SHACK:  Well, there is research
           in lines 231, 232, 233, where you essentially define
           necessary features of PRAs.
                       MEMBER APOSTOLAKIS:  Well, but that's part
           of this activity.  This is not where we talk about
           necessary and sufficient, is it?
                       MEMBER KRESS:  No.  We'll get to that.
                       MEMBER WALLIS:  I thought we ought to
           retain it, because this is a major issue with the --
           it's on the Commission's radar screen.  They are
           worried about PRA quality and how to respond to
           critics.  The quality is so lousy you can't use it,
           and --
                       MEMBER BONACA:  We can put in a statement,
           George, that affects your point of view.  This has
           already been dealt with in large part.  We recognize
           that.  But it's as important --
                       MEMBER KRESS:  Well, let me tell you what
           my take is on this.  My take is is the industry and
           the agency are on divergent courses.  Industry is
           going out to -- through a certification process to
           certify the plant-specific PRAs.  And the agency is
           going forth with this development of standards.
                       And I see the two as somewhat similar but
           not completely compatible.  And what I think will
           happen is the agency will have this set of standards
           to look at, but the industry will come in for some
           request for an exemption or a change or rule --
           rulemaking or whatever, and the plant that comes in
           will bring his certified PRA certified by the industry
                       And the staff will be sitting there with
           another whole set of standards.  And they will have to
           somehow reconcile the two, and that's what I'm asking
           for here is to give some thought to how they're going
           to reconcile the two and see if there is some
           relationship between the standards and the
           certification, and maybe even adopt one or the other
           or both of them, show how they're related to each
                       So I thought we needed a section on
           standards to deal with what I see as an upcoming
           issue.  And that's why I didn't want to zap this
                       CHAIRMAN SHACK:  But I thought they
           already had a program in place to --
                       MEMBER KRESS:  Yes, they have --
                       CHAIRMAN SHACK:  -- at how good -- you
           know, whether the peer review was a grade 3 -- is
           adequate for Option --
                       MEMBER KRESS:  Well, I'm sorry, I didn't
           see --
                       MEMBER APOSTOLAKIS:  And also, didn't the
           staff also report some time ago where they had the
           necessary features?  That was really nice, where they
           also had Appendix B and we recommended that they
           expand the --
                       MEMBER KRESS:  They had necessary but not
                       MEMBER APOSTOLAKIS:  But it's not
           sufficient here either.  In fact, it says sufficiency
           is very difficulty.  So all of these things either
           have been done or are in the process of being
           completed.  That's all.
                       MEMBER KRESS:  Well, you know, everything
           we talk about is -- I don't know why this one should
           be different.
                       MEMBER WALLIS:  They don't want to --
                       MEMBER APOSTOLAKIS:  I don't see it as
           research.  But, anyway, I'm not going to --
                       MEMBER KRESS:  Well, research is a good --
           has got a broad envelope in this agency.
                       MEMBER APOSTOLAKIS:  All right.  Well,
           that's fine with me.  We can keep it.  I didn't feel
           strongly about it.  It's just that I thought it was
           something that was being done anyway. 
                       But this also is nice because it says
           clearly that you cannot define "sufficiency"
           requirements, which we will remember a little bit
                       MR. EL-ZEFTAWY:  That word has been taken
           out, the 242 -- line 242.  When it comes to
           sufficient, we took the word "sufficiency" --
                       MEMBER APOSTOLAKIS:  Where is 242?  That's
           on -- what do you mean?
                       MR. EL-ZEFTAWY:  But, I mean, originally
           we had "sufficient and necessary," and we took the
           word "sufficient" out.
                       CHAIRMAN SHACK:  On 242, it was "necessary
           and sufficient features of probabilistic risk
           assessment" once upon a time.  That -- we nailed that
                       MEMBER APOSTOLAKIS:  Okay.  So that's an
           old letter.
                       CHAIRMAN SHACK:  Yes.
                       MEMBER WALLIS:  So as long as the PRA
           methods are insufficient, that would be okay?
                       CHAIRMAN SHACK:  Yes.
                       MEMBER APOSTOLAKIS:  Okay.  So we could --
           so we keep that.
                       MEMBER KRESS:  So we keep this, and that
           resolves that issue.  Well, we're making headway. 
           These other things I think --
                       CHAIRMAN SHACK:  Well, I think there's a
           question why George wants SPAR out.
                       MEMBER KRESS:  Yes, that's on 13.
                       MEMBER APOSTOLAKIS:  Because it's --
           really, the whole thing addresses the issue of codes. 
           SPAR is a model.  I mean, they are taking the IPs and
           putting them on SAPPHIRE, right?  Is that what SPAR
           is, essentially?  No?
                       MR. KING:  Well, it's not taking the IPs. 
           It's taking our own models, which in many cases are
           better than what the IPs had.
                       MEMBER APOSTOLAKIS:  Right.  Right.
                       MEMBER KRESS:  But they are in a sense
           PRAs.  They're very --
                       MR. KING:  No, plant-specific now.  We've
           got -- we're developing SPAR models for each plant.
                       MEMBER KRESS:  But they could not --
                       MEMBER APOSTOLAKIS:  But the whole point
           of this paragraph was to address the need to peer
           review the fundamental tool of SAPPHIRE.  Now, whether
           you use SAPPHIRE to do other things, I mean, I would
                       CHAIRMAN SHACK:  Well, I thought it was
           more risk assessment tools.  I was going to suggest
           changing lines 241 and 242 to read, "An agency effort
           to define the kinds of risk assessment tools needed to
           support regulatory processes might well provide the
           agency" --
                       MEMBER APOSTOLAKIS:  In my mind, the
           important recommendation is 244.  The SAPPHIRE code
           has reached a stage of development that the public
           deserves to see a comprehensive peer review of this
           code.  This is the message here.
                       MEMBER KRESS:  Yes.
                       CHAIRMAN SHACK:  But I think Dana has been
           adamant that they need better risk assessment tools,
           and so I think he would look at both the --
                       MEMBER APOSTOLAKIS:  But we say that
           somewhere else.  This is not the place.  This is -- he
           doesn't discuss SPAR.  He just mentions them in
                       MEMBER KRESS:   That's the only place in
           here we say anything about SPAR.
                       CHAIRMAN SHACK:  Well, I mean, you might
           say we ought to say more about SPAR, but I'm not sure
           we should argue we should say less.
                       MEMBER BONACA:  I agree with that.
                       MEMBER APOSTOLAKIS:  Look at the first
           sentence.  "The NRC risk assessment codes and models
           continue to undergo development, and the vision of
           this code" --
                       CHAIRMAN SHACK:  These codes and models.
                       MEMBER KRESS:  I think it's --
                       MEMBER APOSTOLAKIS:  I think it dilutes
           it.  I think it really is the SAPPHIRE thing that
           needs the review.
                       MEMBER KRESS:  Do you want to take us --
                       MEMBER APOSTOLAKIS:  I mean, we're asking
           them to do a peer review of a SPAR model?
                       CHAIRMAN SHACK:  No.  No, no.  All we're
           saying is they should continue the development, and
           we'd just like a little better, more organized picture
           of what they really intend to get to with the SPAR
           models.  How good do they need to be?  How good are
           they?  How good --
                       MEMBER APOSTOLAKIS:  Where does it say
           that?  It doesn't say that?
                       CHAIRMAN SHACK:  Well, it's -- if we say
           an agency -- you have to define the kinds of risk
           assessment tools needed to support regulatory process
           -- might well provide the agency with a more scrutable
           strategy for the development of these models and
                       MEMBER KRESS:  Yes, I wouldn't be against
                       CHAIRMAN SHACK:  You know, changing the
           words a little bit.
                       MEMBER APOSTOLAKIS:  Sometimes asking for
           too much means you are getting nothing back.  I think
           if you have a specific recommendation, take this code
           and peer review it.  It's very hard to say, "There are
           ways around it."  Developing better models, yes, we
           are development better models.  What do you want?  I
           think it dilutes the message.  The message is breaks
           of power are so important to have some sort of peer
           review to -- I don't care about the --
                       MEMBER KRESS:  Let's take the -- the
           proposal is to remove the word "SPAR" from here and
           just have this paragraph focus specifically on
           SAPPHIRE.  Those in favor of that, please raise your
           right hand.  Those opposed?  So it passed three to two
           to -- so we're going to remove that "and SPAR," and
           this paragraph is just going to --
                       MEMBER APOSTOLAKIS:  Now, what are we
           going to do about line 241?  The necessary features of
           probabilistic risk assessment support -- are you still
           leaving that there?  I think it's okay to leave it. 
           I mean --
                       MEMBER WALLIS:  Let's leave it.
                       MEMBER APOSTOLAKIS:  -- it's sort of a
           model for --
                       MEMBER KRESS:  Let's leave it.  Let's
           leave it.
                       MEMBER APOSTOLAKIS:  Okay.
                       MEMBER BONACA:  It's mentioned as part of
           the -- from your report?
                       CHAIRMAN SHACK:  I believe so.
                       MR. EL-ZEFTAWY:  So it's even from line
                       MEMBER APOSTOLAKIS:  Yes, the SAPPHIRE
                       MR. EL-ZEFTAWY:  Okay.
                       MEMBER APOSTOLAKIS:  Right.
                       MEMBER KRESS:  Okay.  That takes care of
           that problem.  Now, where should we go?  Let's see
           what's on page 25.  Let's look at 15.  That's the next
           one.  That's the next contentious issue.  That's the
           quantification of uncertainties.
                       MEMBER APOSTOLAKIS:  I was the one getting
           kind of --
                       MEMBER WALLIS:  No, it's very important
           that we do that.
                       MEMBER APOSTOLAKIS:  Well, my point was
           that this is also too dilute.  Let's --
                       MEMBER WALLIS:  Be stronger about it?
                       MEMBER APOSTOLAKIS:  We worry about
           uncertainty, and so on.  I think our message is that
           in the context of these new thermal-hydraulic codes,
           we'd like to see statement of model uncertainty.
                       MEMBER KRESS:  This had to do with PRA.
                       MEMBER WALLIS:  We'd like uncertainty
           evaluated everywhere, including PRA, as a separate --
                       MEMBER APOSTOLAKIS:  Well, I mean, if you
           do that there, that's PRA.
                       MEMBER WALLIS:  Yes, well, this is a PRA. 
           We're talking about PRA.
                       MEMBER APOSTOLAKIS:  And what they say in
           the PRA context, "Please address the issue of
           uncertainties and quantify them," again, is a
           motherhood statement.  Because PRA is supposed to do
           that.  If you don't do an uncertainty calculation, you
           are not doing a PRA.  So I thought the message was
           clearer in the other sections.
                       MEMBER KRESS:  Yes.  But what this makes
           a point is that the uncertainty development in PRAs is
           mostly epistemic and they don't deal with the
           aleatory --
                       MEMBER APOSTOLAKIS:  And they don't know
                       MEMBER KRESS:  Well, we're saying here the
           only place you have both of those combined is in the
           NUREG 1150.  And you need to somehow separate the two
           out and use some generic measure of the aleatory and
           let the codes go ahead and develop the epistemic.  But
           at the end you add the two together some way.
                       You have to deal with both uncertainties
           some way in your development.  Either -- either you do
           it in your -- how you make your decision using the
           results, or you make an assessment of them some way. 
           But it says you need to deal better with
                       And it also makes an interesting point
           that -- to be careful somewhat with the Bayesian
           process because it knocks off details.  And that's an
           important message, too.
                       MEMBER APOSTOLAKIS:  I wrote that.
                       MEMBER KRESS:  You wrote that?
                       MEMBER APOSTOLAKIS:  But I'm proposing to
           eliminate it, because I think it's --
                       MEMBER KRESS:  No, no, it's an important
                       MEMBER WALLIS:  George, it's not as if
           they don't know it.  If they know it, we're simply
           reinforcing it.  And the fact that we wrote it in our
           report will help them.  So --
                       MEMBER KRESS:  The staff probably knows
           99 percent of everything that --
                       MEMBER APOSTOLAKIS:  Can we get -- well,
           it's not a matter of that.  Well, one thing we don't
           do right now is send the reader to other sections
           where similar things are discussed.  Like here I think
           it would be very appropriate on line 301 if we
           actually send them to the thermal-hydraulic section.
                       MEMBER WALLIS:  That would be fine.  That
           would be fine.
                       MEMBER APOSTOLAKIS:  That would make me
                       MEMBER WALLIS:  That would be fine.
                       MEMBER KRESS:  I wouldn't be opposed to
                       MEMBER APOSTOLAKIS:  Yes.  I mean, this
           thing about -- as you know, we sent many e-mails to
           Dana back and forth.  When I discussed this issue of
           updating the distributions it was in a very different
                       MEMBER KRESS:  Yes.
                       MEMBER APOSTOLAKIS:  So I thought it was
           a little bit out of the blue.  But it's okay.  I mean
                       MEMBER KRESS:  Well, it fits you.  I guess
           the word fits.  So we'll retain this, and maybe add a
           sentence at the end that refers to the thermal-
           hydraulic section that deals with this same issue.
                       MEMBER APOSTOLAKIS:  Now, if we retain it,
           look at 294.  "Uncertainness in the models used for
           the analysis are seldom discussed."  Is that correct? 
           I don't think it's correct.
                       MEMBER KRESS:  That one we might want to
                       MEMBER APOSTOLAKIS:  They may not be
                       MEMBER WALLIS:  We should take that out.
                       MEMBER APOSTOLAKIS:  But they are
           certainly discussed.  So let's take that out.
                       MEMBER KRESS:  I thought we could deal
           with those kinds of things later.  Well --
                       MEMBER APOSTOLAKIS:  Also, on 293, of
           propagating parameter uncertainties, we don't need the
           word "epistemic" there.
                       MEMBER KRESS:  293?  Yes, you're right. 
           It's redundant.  
                       MEMBER APOSTOLAKIS:  Now --
                       MEMBER KRESS:  Besides, anywhere I can
           mark out the words "epistemic" and "aleatory" I am
           willing to do --
                       MEMBER APOSTOLAKIS:  291.  Yet careful
           quantification of the -- it's not -- there's a typo
                       MEMBER KRESS:  Yes, there are a couple of
                       MEMBER APOSTOLAKIS:  Yes.  Of
           uncertainties seldom appears in risk-informed
           regulatory discussions.  Do we all agree with that?
                       MEMBER KRESS:  Well --
                       MEMBER APOSTOLAKIS:  Quantification.  Yes,
           probably right.  Quantification is correct.  The
           discussion was incorrect.  
                       Okay.  So just make sure that at the end
           we put "see also Section 6."  Go to the end of the
           paragraph, and --
                       MEMBER WALLIS:  Is it only in Section 6
           that we want to --
                       MEMBER APOSTOLAKIS:  Well, that's where
           the thermal-hydraulic is.  Is there another place?  I
           think that's the main place.
                       MEMBER KRESS:  I think that's the main
           place it's in here.
                       MEMBER APOSTOLAKIS:  See Section Roman
           II.6.  Thank you.  Okay.  Let's keep it.
                       MEMBER KRESS:  Good.  Let's go to page 25. 
           That's another simple one.  Oh.  The suggestion was to
           delete that -- what should be the -- at the end of
           that.  I oppose that suggestion because --
                       MEMBER APOSTOLAKIS:  Well, isn't the
           second bullet -- sub-bullet -- where is it?  Oh. 
           Asking the same thing?  When is human performance at
           the nuclear plant good enough?  In fact, I prefer that
           than what it should be, and that was what dictating --
           the human error contribution should be 30 percent.  So
           that's why I proposed to take it out.  Personally --
                       MEMBER KRESS:  I think you're right,
                       MEMBER BONACA:  I think so.
                       MEMBER KRESS:  I think you're right. 
           Let's zap that.
                       MEMBER APOSTOLAKIS:  You win a few, you
           lose a few.
                       MEMBER KRESS:  Yes.
                       MEMBER APOSTOLAKIS:  You lose a lot, you
           win a few.
                       No, no.  No.  Delete, "What should they
           be?"  The red.
                       MEMBER KRESS:  Okay.
                       MEMBER APOSTOLAKIS:  Then, you want us to
           go to 33?
                       MEMBER KRESS:  Yes, we might as well go
           right down the line here.  Then we'll get back to six,
           eight, and nine.
                       MEMBER APOSTOLAKIS:  So this is alternate
           now to what again?
                       CHAIRMAN SHACK:  Hold on a second.
                       MEMBER APOSTOLAKIS:  To all the bullets?
                       CHAIRMAN SHACK:  Yes.  Yes.  
                       MR. EL-ZEFTAWY:  Yes.  It's all the --
                       MEMBER KRESS:  The suggestion was to zap
           out all of --
                       MR. EL-ZEFTAWY:  Actually, it's line 631.
                       MEMBER KRESS:  Yes, and replace it with
           this tiny little sentence.  Yes.  And I think Bill
           Shack could -- could discuss why he thinks this is a
           good idea maybe.
                       CHAIRMAN SHACK:  Okay.  I just felt that
           basically you had better -- there were better points
           made in the discussion of the specific topics than
           there were here.  I mean, these bullets didn't really
           -- couldn't even make the case.  You know, whether the
           model is -- doesn't have the technical sophistication
           that you have at NIST is not really the question.  The
           question is, is it good enough?  
                       I don't know that it's, you know,
           specialized activities that can't be done by the
           regional staff and require -- you know, it does --
           this didn't strike me as very forceful arguments for
           why I needed research.  I had much more forceful
           statements I thought in the discussion of the specific
           tools.  And so I thought it actually strengthened the
           argument to get on with it.
                       MEMBER KRESS:  And my feeling was that
           these are relatively true statements, all of them --
           the bullets.  So it didn't hurt much to leave them in
           to set in -- give a context for the -- it didn't hurt
           to leave them in.  And Dana -- they were close to
           Dana's heart, and so my feeling was it -- if it didn't
           hurt to leave them in, why not just leave them in?
                       CHAIRMAN SHACK:  Well, for example, in
           631, this his what -- you know, we argue about when
           the staff should be doing things and when the industry
           should be doing things.  It's not at all clear to me
           that this is a -- you know, that it's something that
           shouldn't be done by the industry, for example.
                       MEMBER KRESS:  Well, if you're going to
           risk-inform it -- the process, then it's something
           that the agency ought to do.
                       CHAIRMAN SHACK:  I think the industry
           should be -- you know, required to analyze
           consequences of the accidents.
                       MEMBER KRESS:  Maybe what you -- how you
           risk-perform it is --
                       CHAIRMAN SHACK:  Well, to facilitate the
           circuit analysis sounds to me like a licensee --
                       MEMBER BONACA:  You know, I don't think,
           though, the bullets here are created equal.  I think
           we should look one by one, because some of them, for
           example, I agree to retain.  That first one -- it's an
           important observation.  I think the fact that, you
           know, the NRC to have the technical sophistication of
           -- developed by -- it's an observation of --
                       MEMBER KRESS:  I think we've used up our
           hour.  Should we defer this to --
                       CHAIRMAN SHACK:  No, we've got until 9:30. 
           We've got half an hour.
                       MEMBER KRESS:  Oh, do we? 
                       MEMBER BONACA:  Yes.
                       MEMBER KRESS:  Okay.  Thank you.  
                       CHAIRMAN SHACK:  We're doing good.
                       MEMBER BONACA:  Yes.  The second bullet,
           for example, I could do without.  I mean, so what's
           the problem?  If you need to obtain a specialist for
           the important stuff, I mean --
                       MEMBER KRESS:  I wouldn't want to be
           without that second bullet.
                       MEMBER BONACA:  What?
                       MEMBER KRESS:  I wouldn't want to be
           without that second bullet.  Neither would Dana.
                       MEMBER SIEBER:  Neither would I.
                       MEMBER KRESS:  I've got two votes.  If I
           raise my left hand, it's Dana.  If I raise my right
           hand, it's --
                       MEMBER BONACA:  No.  I mean, I think we
           should walk through the bullets now and discuss --
                       MEMBER KRESS:  Yes.
                       MEMBER BONACA:  -- them all.  I think some
           of them I agree with and some of them I don't agree
                       MEMBER KRESS:  Well, I certainly wouldn't
           want to get rid of bullet number three.  I might be
           willing to get rid of bullet number four.
                       CHAIRMAN SHACK:  Okay. 
                       MEMBER KRESS:  And five.  I would like to
           retain the first three bullets and get rid of --
                       MEMBER BONACA:  I can go with that.
                       MEMBER APOSTOLAKIS:  How many?
                       MEMBER KRESS:  The first three.
                       MEMBER APOSTOLAKIS:  The first two?
                       MEMBER KRESS:  The first three.
                       MEMBER APOSTOLAKIS:  And replace them by
           the alternate or just --
                       MEMBER KRESS:  Well, the alternate might
           be something we'd want to replace them with.  No, no,
           the alternate would -- we said that to some extent in
           the --
                       MEMBER APOSTOLAKIS:  Right.  So eliminate
           the first three bullets.
                       MEMBER KRESS:  Yes.  No, the last two.
                       MEMBER APOSTOLAKIS:  Wait a minute.  Wait
           a minute.  You are eliminating --
                       CHAIRMAN SHACK:  The last two.
                       MEMBER APOSTOLAKIS:  The significance of
           the termination process?
                       MEMBER KRESS:  Yes.  But read the whole
           thing, George.  I mean, what -- I mean, I don't think
           that's very helpful to the --
                       MEMBER APOSTOLAKIS:  Right, right, right.
                       MEMBER KRESS:  You know, the important --
                       MEMBER APOSTOLAKIS:  I would say it is
           based on evaluations that are not at all transparent
           to the public.
                       MEMBER KRESS:  Well, I would probably
           agree with leaving it in if you --
                       MEMBER APOSTOLAKIS:  Yes.
                       CHAIRMAN SHACK:  Transparency to the
           public is --
                       MEMBER APOSTOLAKIS:  Or transparent,
                       CHAIRMAN SHACK:  Until we've gone through
           the STP, I'm -- you know, that's sort of my thing, is
           that we --
                       MEMBER KRESS:  We haven't really reviewed
           the --
                       CHAIRMAN SHACK:  -- we haven't reviewed
                       MEMBER APOSTOLAKIS:  Well, but in that
           spirit, have you really reviewed the NIST code?  And
           do you know that it's much better than --
                       CHAIRMAN SHACK:  Hey, I voted for
           eliminating all of the bullets myself.
                       MEMBER APOSTOLAKIS:  I think something
           about the STP is important.  I mean, you can say they
           are not at all transparent, but, you know --
                       CHAIRMAN SHACK:  It would be helpful if I
           had read it and I knew what it was.
                       MEMBER APOSTOLAKIS:  It would have been
           helpful, yes.
                       MEMBER WALLIS:  I think Dana has read it.
                       CHAIRMAN SHACK:  Yes.  But my comment was
           that I think Dana may be the only one that has read
           it.  And, you know, this is a committee position.
                       MEMBER BONACA:  This could be a true
           statement and transparent -- and much of the
           regulations are transparent to the public.
                       CHAIRMAN SHACK:  right.
                       MEMBER APOSTOLAKIS:  So why would we say
           "not at all transparent to the public"?  But it
           doesn't matter?  Because the other regulations are the
           same way.
                       MEMBER KRESS:  Yes, that's my point.  I
           don't think it has to be transparent.
                       MEMBER WALLIS:  Well, I'd be happy to
           remove it.  We don't really seem to be certain that we
           want to say --
                       MEMBER KRESS:  Let's zap those two.
                       MEMBER APOSTOLAKIS:  Yes.
                       MEMBER KRESS:  Yes.
                       MEMBER APOSTOLAKIS:  I'm not sure about
           the first bullet.
                       MEMBER KRESS:  Okay.  Let's go back to --
                       MEMBER APOSTOLAKIS:  Is it the case of the
           grass being greener on the other side?
                       MEMBER KRESS:  Well, I think it's a case
           of --
                       CHAIRMAN SHACK:  But even if it's not, it
           doesn't -- you know, I'm sure there are lots more
           technical sophisticated ways to do lots of things. 
           The question is, you know, is it good enough?
                       MEMBER APOSTOLAKIS:  And I'll submit the
           overall fire risk assessment methodology that is used
           by the fire community is not as sophisticated as ours. 
           Maybe individual tools are a little better.
                       MEMBER BONACA:  But given the significance
           of fire risk, okay, given the significance of fire
           risk, I think that, you know, that's a statement that
           says we have expectations that the NRC had the better
           -- had these available, acknowledge that it's not
           being used right now.
                       MEMBER APOSTOLAKIS:  Well, really, the
           message should be that the technical sophistication of
           our tools is behind that of the state of the art. 
           That is more accurate I think.
                       MEMBER KRESS:  Yes, why don't we say that.
                       MEMBER APOSTOLAKIS:  But to compare now
           with NIST and --
                       MEMBER KRESS:  Yes, I think you're right,
           George.  Let's do it that way.
                       MEMBER APOSTOLAKIS:  Okay.
                       MEMBER KRESS:  Give her the --
                       MEMBER APOSTOLAKIS:  Huh?
                       MEMBER KRESS:  Give her what that --
                       CHAIRMAN SHACK:  We'll work on it later,
           and we'll -- just move on.
                       MEMBER APOSTOLAKIS:  The technical
           sophistication of models that appear in the
           literature --
                       MEMBER KRESS:  I think we're going to zap
           the red part of it.
                       MEMBER APOSTOLAKIS:  We're zapping what?
                       MEMBER KRESS:  This.
                       MEMBER BONACA:  The alternate?
                       MEMBER APOSTOLAKIS:  Oh, the alternate. 
           Yes, that goes.
                       MEMBER KRESS:  Okay.  We will work on that
                       MEMBER APOSTOLAKIS:  Okay.  And we're
           keeping everything else?  What?
                       CHAIRMAN SHACK:  Did you take out -- the
           last two bullets went.
                       MEMBER APOSTOLAKIS:  Oh, the
           significance --
                       CHAIRMAN SHACK:  The significance of
           termination and --
                       MEMBER SIEBER:  And the first one gets
                       MR. DURAISWAMY:  Hey, Tom, excuse me.  You
           just took out the last two bullets?  The last one,
                       MEMBER KRESS:  Yes.
                       MR. DURAISWAMY:  But the last one I think,
           you know, they've got some problems between the
           industry and the staff. 
                       MEMBER KRESS:  But that's why --
                       MR. DURAISWAMY:  I don't think you should
           take it out.
                       MEMBER APOSTOLAKIS:  No.  But I agree with
           Bill here.  It's not obvious to me that there are
           computational methods that could be developed to
           facilitate it.  Have we ever investigated that?  Is it
           obvious to everybody else?
                       MR. DURAISWAMY:  Well, that's why I think
           we've got to set up a subcommittee to --
                       MEMBER APOSTOLAKIS:  Yes.
                       MR. DURAISWAMY:  -- talk about that and --
                       MEMBER APOSTOLAKIS:  I cannot say right
           now that obvious computational methods could be --
                       CHAIRMAN SHACK:  The "obvious" has to go,
           if nothing else goes.
                       MEMBER WALLIS:  If you're going to say
           this, I would have a period after "fires," and cut out
           this and simply start, "Computational methods should
           be developed to" --
                       MEMBER APOSTOLAKIS:  That makes me much
                       MEMBER KRESS:  Well, do we want to put --
                       MEMBER APOSTOLAKIS:  Take out "when
           obvious."  And capitalize "computational."
                       MEMBER WALLIS:  But a period here, too.
                       MEMBER APOSTOLAKIS:  Where are you now? 
                       MEMBER WALLIS:  No, no, no.
                       MEMBER APOSTOLAKIS:  We zapped it.
                       MEMBER KRESS:  Let's put it back in.
                       MR. EL-ZEFTAWY:  So you're just taking out
           one "obvious"?  Is that the only thing you're going to
           take out?
                       MEMBER WALLIS:  "Computational methods
           should be developed."  Should instead of could.
                       MR. EL-ZEFTAWY:  And there's a period
           after "developed."
                       MEMBER WALLIS:  To facilitate the --
           analysis, risk-inform the--
                       MR. EL-ZEFTAWY:  Okay.
                       MEMBER KRESS:  I would put a statement
           when --
                       MEMBER APOSTOLAKIS:  Is it really a
           controversy with the licensees?
                       MEMBER WALLIS:  Yes, I think you might
           want to change that, too.  I would say something --
           "Staff finds itself disagreeing with licensees" or
           something like that.
                       MEMBER APOSTOLAKIS:  Yes.
                       MEMBER WALLIS:  Or in disagreement with --
                       MEMBER APOSTOLAKIS:  Yes, finds itself in
                       MEMBER WALLIS:  Or it simply disagrees. 
           Do we need to "find itself in disagreement"?
                       MEMBER APOSTOLAKIS:  Disagrees.  That's --
                       MEMBER KRESS:  Get rid of "finds" in that
                       MEMBER APOSTOLAKIS:  So you go to fires,
           put a period, on the second line?
                       MEMBER KRESS:  Yes.
                       MEMBER APOSTOLAKIS:  Delete "when obvious"
           and capitalize C.
                       MEMBER WALLIS:  And then have "should"
           instead of "could."
                       CHAIRMAN SHACK:  And we'll leave it to the
           highly paid arbitrator to straighten out the
           constructions of the other bullets.
                       MEMBER KRESS:  Yes, Sam can do that.
                       MR. DURAISWAMY:  Not highly paid, but --
                       MEMBER KRESS:  Let's go to 36.  This is
           a --
                       MEMBER APOSTOLAKIS:  Oh, you're going to
           another page?  Oh, I had a question on line 640.
                       MEMBER KRESS:  640?
                       MEMBER APOSTOLAKIS:  Yes.  The ACRS has
           reviewed the plan and the concurs with the research
           program -- that the plan sets forth.  When did --
                       MEMBER KRESS:  Oh, we did that.  Yes, that
           was -- we did that a couple of weeks -- months ago. 
           That was --
                       MEMBER APOSTOLAKIS:  A couple of months
           ago we wrote a letter?
                       MEMBER KRESS:  Steve Arntz.
                       MEMBER APOSTOLAKIS:  The fire protection
                       MEMBER KRESS:  No, it wasn't.
                       MEMBER APOSTOLAKIS:  Yes, that was --
                       MEMBER WALLIS:  Wasn't this a Jack Sieber
           thing or --
                       MEMBER KRESS:  Yes, that was --
                       MEMBER SIEBER:  We all got copies of
           the --
                       MEMBER WALLIS:  Did we actually agree on
           it.  There's a huge fat thing that came out and --
                       MEMBER SIEBER:  Yes, three-eighths of an
           inch thick.
                       MR. DURAISWAMY:  Did you write a letter,
                       MEMBER SIEBER:  Pardon?
                       MR. DURAISWAMY:  Did you write a letter?
                       MEMBER SIEBER:  No.
                       MR. DURAISWAMY:  So then you can't say
           ACRS completed the --
                       MEMBER SIEBER:  We never got it
                       MEMBER APOSTOLAKIS:  Okay.  Why don't we
           delete the sentence?
                       MEMBER KRESS:  Just zap the last sentence. 
           Thank you, Sam.
                       MEMBER APOSTOLAKIS:  Keep going.  Keep
           going.  Is it longer or shorter now?
                       MEMBER KRESS:  Keep going to the -- whoa.
                       MEMBER APOSTOLAKIS:  Wait.  No, no, no,
           no.  We are in the next section now.  Go back.  Well,
           it's not 640 anymore.  Go back more.
                       MEMBER KRESS:  Okay.  There it is.  641. 
           No, it's --
                       MEMBER APOSTOLAKIS:  Go back some more.
                       MEMBER KRESS:  Okay.  Thank you.
                       Now, let's look at page 136.  George, I
           think this is a debate between you and Mario.
                       MEMBER BONACA:  Yes.  I would say that the
           statement we had before that says "would surely" is
           too strong.  I agree with that.  The words I had
           originally was "is likely to."
                       MEMBER APOSTOLAKIS:  Sorry?  What were the
                       MEMBER BONACA:  "Is likely to."  It might. 
           So I would change "would surely" to "is likely to" and
           Bill is proposing "could."  I just wanted to make sure
           it wouldn't be too --
                       MEMBER APOSTOLAKIS:  I would say "could"
           is more neutral, isn't it?
                       MEMBER KRESS:  Yes.  "Is likely to" means
           it is likely to.  "Could" means there's --
                       MEMBER BONACA:  That's my judgment.  At
           this stage it's a judgment.  Certainly, if it is just
           a might --
                       MEMBER APOSTOLAKIS:  No, the "might" I
           think is too weak.  
                       CHAIRMAN SHACK:  "Could" is stronger than
           "might" and weaker than "is likely to."
                       MEMBER KRESS:  "Could" is so weak that it
           always applies.  "Could" is about as weak as you can
                       MEMBER APOSTOLAKIS:  Replace "might" by
                       MEMBER BONACA:  I don't know. 
                       MEMBER APOSTOLAKIS:  No?
                       MEMBER BONACA:  Are you sure?  You don't
           think about "is likely to"?  I understand that we're
           implementing a regulation and that affects --
           therefore, you know, PRA, you may have --
                       MEMBER WALLIS:  Well, I sort of support
           Mario that this is old, and surely something has
                       MEMBER BONACA:  If you make it too weak,
           the whole section becomes into question.  Why have a
           full section proposing something if you're really
           making a statement that is so weak that says "so
           what?"  I mean, if really aging is not an issue, and
           you can have this plant at 600 years of age, I mean,
           why propose --
                       MEMBER KRESS:  Well, we could say results
           could show increases in risk metrics.  That's almost
           certain.  I don't think they're going to go down.
                       MEMBER WALLIS:  It implies that we think
           it's likely.
                       MEMBER KRESS:  Yes.  But even if it's
           likely, this doesn't address the question of whether
           George's statement that it's already so low that an
           increase doesn't make much difference gets lost in the
           noise.  I think that's a significant statement.
                       MEMBER BONACA:  I think George was
           focusing mostly on main components for the vessel
           rather -- I'm thinking about total -- I'm thinking
           about those nozzles that we saw cracked, and the UT
           failed to detect it.
                       MEMBER WALLIS:  Well, I suggest no word at
           all.  PRA that could account for aging of structures,
           systems, and components.  Oh, I see.  I'm sorry.  I
           screwed up on that.
                       MEMBER BONACA:  I agree that, you know,
           the statement "would surely" was too strong.  But I
           think that -- I think I believe it's likely to show
           some -- I think it surely would --
                       MEMBER APOSTOLAKIS:  The end part program
           of several years ago did not find any significant
           failures due to aging.  It found partial degradation,
           things like that, but, hence, to see the impact of
           aging on failure rates have reached no conclusions. 
           There is no evidence that the failure rates increase.
                       When we did the small study at MIT, again,
           we were hard pressed to really find a significant
           change in probabilities of core damage, and so on. 
           That's why I'm reluctant to be very positive that,
           yes, we will find an impact.  On the other hand, I'm
           not ready to say, no, there will be no impact.  So, I
           mean, what --
                       MEMBER BONACA:  So this is -- I've been
           thinking about the experience we had from industrial
           facilities other than LOCA, is that when it reaches
           end of life, even with the proper maintenance it
           becomes so troublesome that they get shut down just
           for economic reasons.
                       Now, here the implication is that those
           kinds of, you know, compounding failures you see more
           leaks here and there, some problems, are not going to
           create a problem from a safety standpoint.  It will
           only create a problem from an economic standpoint, so
           the plants would be retired.  That's really the
           conclusions we are reaching.
                       Well, I think it's a stretch to reach just
           a conclusion.  There is complexity that says, you
           know, common sense is telling me that it could affect
           those there.  If I use "might" -- a section of this
           size, it would be -- 
                       MEMBER APOSTOLAKIS:  I am with you on the
           "might," but do you disagree on using "could"?  Is
           that too weak?
                       MEMBER BONACA:  "Could" is a little weak. 
           I mean, I -- you know, I thought that -- I really
           believe it is likely to show, but I have never made it
           -- we are assuming that --
                       CHAIRMAN SHACK:  But you have Tom's
           problem -- is that surely there are increases.  The
           question is whether they're significant or not.
                       MEMBER BONACA:  Yes, I understand.  Well,
           whatever it says, we believe in fact that they are not
           insignificant because of the --
                       MEMBER WALLIS:  I have a different way of
           putting it.  A PRA that could account for aging of
           structures would provide measures of increases in -- 
                       MEMBER BONACA:  That's not the meaning of
           this.  What we intended to say is that we would see
           some increase due to the fact that you have increased
           failure rates of some type, and then the discussion of
           how you would contribute to those increases.
                       MEMBER WALLIS:  But I think your
           colleagues object to the distinction that there are
           going to be increases.
                       CHAIRMAN SHACK:  Graham gets us around
           that problem.  I think his says --
                       MEMBER WALLIS:  Yes, I had a time where
           there's going to be increases or not.
                       MEMBER BONACA:  Could you repeat your --
                       MEMBER WALLIS:  I said -- well, take what
           we've got.  A PRA that could account for aging
           structures, systems, and components, would provide
           measures of increases in risk metrics, such as core
           damage frequency.  We don't even need to say
                       MEMBER APOSTOLAKIS:  It's a neutral
                       MEMBER BONACA:  I agree.
                       MEMBER APOSTOLAKIS:  It's more neutral.  
                       MEMBER BONACA:  I agree.
                       MEMBER APOSTOLAKIS:  It says we want to
                       MEMBER BONACA:  Right.  I agree.  And
           that's important for the --
                       MEMBER WALLIS:  Without trying to guess if
           it's going to be --
                       MEMBER BONACA:  I agree with that.
                       MEMBER APOSTOLAKIS:  All right.  So will
           you tell Sheri what to do there?
                       MEMBER WALLIS:  Where are we?  Take out
           all the red.  Take out the "might."  Take out the red
           stuff.  Okay.  And then take out "show."  Would
           provide measures of --
                       MEMBER APOSTOLAKIS:  No, "would surely"
                       MEMBER WALLIS:  Would provide -- instead
           of "increases," which occur -- okay.  Take that out. 
           Okay.  Would provide measures of -- a long sentence. 
           Increases in -- has aged.
                       MEMBER APOSTOLAKIS:  And I would put a
           period there and say, "These increases are due to" --
                       CHAIRMAN SHACK:  Yes, the sentence is too
                       MEMBER APOSTOLAKIS:  Go back.  Not right
           there.  You want to put it after "operations" comma. 
           As aged from 40 years to 60 years of operation.  And
           then this increase would be expected due to increases
           -- there are too many "expecteds."  
                       MEMBER WALLIS:  Just take out the second
                       MEMBER APOSTOLAKIS:  Yes. 
                       MEMBER WALLIS:  The second "expected." 
           Well, due to a higher failure probability.
                       CHAIRMAN SHACK:  An increase in failure
           probability along with components.  Good enough. 
           That's okay.  Is that --
                       MEMBER WALLIS:  Should we leave up to the
           "highly" --
                       CHAIRMAN SHACK:  Yes.
                       MEMBER APOSTOLAKIS:  So, essentially, what
           we're saying is that even though the plants meet the
           requirements of the license renewal rule, the risk
           will increase as they're allowed to operate from 40 to
           60 years.
                       MEMBER WALLIS:  And we want to know.  And
           we want to -- they should find out.
                       CHAIRMAN SHACK:  But George has a comment
           on page 37 about some -- you know, the -- we didn't
           say anything that, you know, people are trying to
           manage this.
                       MEMBER BONACA:  But the statement before
           says the risk increase is found to be small because of
           the implementation of requirements which are -- 
                       MEMBER APOSTOLAKIS:  Where is that?
                       MEMBER BONACA:  The statement right before
           that.  It gives credit to -- like 137.  I mean -- has
           extensive modeling programs in place.  That's implicit
           in that statement that --
                       MEMBER APOSTOLAKIS:  Where is that
           sentence that it says --
                       CHAIRMAN SHACK:  137.
                       MEMBER APOSTOLAKIS:  I know the page, the
                       CHAIRMAN SHACK:  The line is 2536 on your
           printed copy.
                       MEMBER KRESS:  538.
                       MEMBER APOSTOLAKIS:  The risk increase is
           small because implementation reserves regulatory
           margins.  Where does it say about --
                       CHAIRMAN SHACK:  Well, I was going to
           change that line to read, "The risk increase may well
           be found to be -- may well be found small because the
           license renewal process is intended to provide
           insurance that aging management programs preserve
           regulatory margins," duh, duh, duh, duh, duh, duh,
                       MEMBER APOSTOLAKIS:  Good.  That's what --
           sounds good.  That's good.
                       MEMBER BONACA:  So give it to Sheri?
                       CHAIRMAN SHACK:  I'll just give it --
           while we're on that page, too, I thought Tom -- we
           focus on the other metrics for power uprates.  That
           sentence on 137 that starts at 2544, I was going to
           suggest changing to, "Assessments of the increases in
           risk associated with license and renewal and power
           uprates may need to consider risk metrics other than
           CDF and LERF."
                       MEMBER KRESS:  Oh, great.  I love that.
                       MEMBER BONACA:  What is the line?
                       CHAIRMAN SHACK:  It's this line.  We just
           focused it purely on power uprates, and I think Tom
           would say that you really need to look at that in a
           broader sense.
                       MR. EL-ZEFTAWY:  If we were to leave the
           last one -- if you look at page 139, line 2579, can
           you tell me if you agree on that change?
                       MEMBER APOSTOLAKIS:  Where?
                       MR. EL-ZEFTAWY:  Page 139.
                       MEMBER APOSTOLAKIS:  Yes, it was approved,
           I thought.
                       MEMBER KRESS:  Yes.
                       MR. EL-ZEFTAWY:  So that's approved?
                       MEMBER APOSTOLAKIS:  Yes.
                       MR. EL-ZEFTAWY:  The e-mail exchange.  All
                       MEMBER APOSTOLAKIS:  Yes, I have no
           problem with that.
                       MEMBER KRESS:  Okay.  Now, I suggest we
           look at -- 
                       MEMBER APOSTOLAKIS:  Any corrections?
                       MEMBER KRESS:  No, not yet.  We'll save
           that to last.  But look on pages 8 and 9, and let's
           deal with those.  I think Bill's suggestion was to
           move some of this around and delete some of it.  He
           wanted to delete the lines highlighted in 140 and 141
           and move lines 152, 153, and 154 up to replace them --
           I think was the suggestion, wasn't it, Bill?
                       MEMBER WALLIS:  What we have is actually
           the new 140/141.  That's an addition to -- the
           highlighted 140/141 is an addition.  It comes from
           152, which has been --
                       MEMBER KRESS:  That's just -- you're
           right.  And my suggestion was to not do that.
                       MEMBER WALLIS:  Okay.
                       MEMBER KRESS:  Is to -- is to delete that
           line 140/141 and retain 152 and --
                       CHAIRMAN SHACK:  Right.  Yes.  I wanted to
           insert that line up there, but I didn't know where to
           put it is all.
                       MEMBER KRESS:  Yes.  My feeling was that
           that sentence doesn't belong up there, because it's an
           entirely different subject matter than the rest of the
                       CHAIRMAN SHACK:  Yes, but read the
           sentence before that, starting on 137, and then look
           at the sentence that starts on 152.  "One would expect
           that the Commission would -- would have available
           comprehensive state-of-the-art assessment tools.  One
           would expect that site-specific risk information would
           be readily available to line organizations
           implementing risk assessment process."  To me they're
           saying exactly the same thing.
                       MEMBER WALLIS:  Yes, it is.  I think
           you're right.  I thought this was okay, sort of a
           compression of the idea.
                       MEMBER KRESS:  Yes, but I would want to --
           I'd still want to get rid of that statement that risk
           assessment remains an activity that --
                       MEMBER WALLIS:  Do you want to remove it
           all together?
                       MEMBER KRESS:  Yes, that part of it I'd
           like to get rid of.
                       CHAIRMAN SHACK:  But would you then retain
           any part of 152 and 154, or that just all goes?
                       MEMBER KRESS:  I would get rid of all of
           it, yes.
                       CHAIRMAN SHACK:  Less is more.
                       MEMBER KRESS:  Yes.  Now, on page 9, Bill
           had added in the shaded part, and I suggested that we
           not add it in.  And his reasoning I think was that
           this is something we're leaving out of the statement
           that's of use, but I -- my feeling was that these
           limited numbers of shutdowns are not useful at all to
           shutdown risk.  I don't even want to refer to them,
           because I think they're useless. 
                       CHAIRMAN SHACK:  For your purposes,
           they're useless.  You know, if you're looking for
           insight, I think they are useful.  You know, they
           don't allow you to compute the average lifetime risk.
                       MEMBER KRESS:  I think they're -- I think
           the statement that they're -- I mean, I think it's
           overly strong to say that you've got scoping
           assessments of shutdown risk at two representative
           plants.  Period.
                       MEMBER WALLIS:  I think they need more
           than that.  They used more information than that.
                       CHAIRMAN SHACK:  That, to me, is just, you
           know, a -- we didn't do it; therefore, we ain't going
           to look at it.
                       MEMBER KRESS:  Well, I'm not strong about
           -- you're right.  I can go along with leaving it in. 
           It doesn't hurt to say this.
                       MEMBER WALLIS:  It's not a lie, is it?
                       MEMBER KRESS:  No.  Well, it's a very
           limited --
                       CHAIRMAN SHACK:  Put in a very --
                       MEMBER APOSTOLAKIS:  Let's leave it in.
                       MEMBER WALLIS:  They did use this
           information.  I mean, it --
                       MEMBER KRESS:  Yes, let's leave it in.
                       Okay.  Now, I didn't have a chance to send
           everybody the suggestions that Graham Wallis had on
           what to do with the -- 
                       MEMBER WALLIS:  I sent them to all of the
           ACRS --
                       MEMBER KRESS:  So you got some suggestions
           from Graham on what to do with the -- with some things
           that may be wrong with the introduction.  And what I
           did was you have before you something that looks like
                       MEMBER APOSTOLAKIS:  Oh, this is Graham's?
                       MEMBER KRESS:  No.  This is my response to
           Graham's suggestions.
                       MEMBER APOSTOLAKIS:  Oh.
                       MEMBER KRESS:  Before you look at it, I
           want to make one correction.  Under two on page 2,
           there's supposed to be an introductory sentence that
           says the examinations of the research programs by the
           ACRS then did not focus on the initial need for the
           research results.  Instead, the exemptions focused on
           the questions.  And then --
                       MEMBER APOSTOLAKIS:  Right.  That's fine.
                       MEMBER KRESS:  That's supposed to be --
                       MEMBER APOSTOLAKIS:  That's fine.
                       MEMBER KRESS:  But this is my -- what I've
           done is just rearranged things.
                       CHAIRMAN SHACK:  Well, you've wiped out
           the whole user needs stuff.
                       MEMBER KRESS:  No, it's supposed to be in
                       CHAIRMAN SHACK:  Did it move somewhere?
                       MEMBER WALLIS:  It wasn't supposed to.
                       MEMBER KRESS:  It just moved.
                       MEMBER WALLIS:  It should be removed
           because --
                       MEMBER KRESS:  Well --
                       MEMBER WALLIS:  -- as it was.
                       MEMBER SIEBER:  Well, I just moved it
           because I wanted you to look at this and see how it
           read and then make a decision whether to black out the
                       MEMBER WALLIS:  Well, you put it in now
           with your added sentence under two.  You said we
           didn't refer to the user needs.  We used these other
           criteria, and that clarifies it.  I don't think we
           need to talk about user needs again, do we?  Because
           we sort of take a swipe at them which isn't justified.
                       MEMBER KRESS:  Where is the user needs
           part in here?
                       MEMBER WALLIS:  On page 5.  Nevertheless,
           motivation -- did not -- we could remove that because
           we've already said that.
                       MEMBER KRESS:  Yes, that's the question. 
           Do we want to leave that in or --
                       MEMBER WALLIS:  Let's take that out
           because it sort of takes a swipe at something we never
           expand upon in any way.
                       MR. EL-ZEFTAWY:  You're talking page 5,
           line -- the paragraph at the top?
                       MEMBER KRESS:  Paragraph in the middle on
           page 5.
                       MR. EL-ZEFTAWY:  Yes. 
                       MEMBER WALLIS:  Actually, we're talking
           about concerns about using the process at the top of
           page 5.
                       CHAIRMAN SHACK:  Right.  It's the first
           paragraph 5.
                       MEMBER WALLIS:  I would like to remove
           both of those paragraphs.
                       CHAIRMAN SHACK:  Yes, I don't think it
                       MEMBER WALLIS:  It says -- it sort of says
           the user needs process is in place, but we've ignored
           it completely because we think it's pretty lousy.  I
           don't think that's what we want to say.
                       CHAIRMAN SHACK:  I'm sure that's what Dana
           wants to say.
                       MEMBER WALLIS:  Is it?  But I'm not sure
           that's what we want to say, is it?
                       MR. LARKINS:  I think Dana's point was
           that, you know, all of the research shouldn't be
           driven by the user need requests, that it should be
           some portion or percentage of the work that's done
           outside of this process, research on its own.
                       MEMBER KRESS:  I suspect everybody would
           agree with this statement.  So I don't know why we
           don't --
                       CHAIRMAN SHACK:  But I thought it was
           cryptic enough as it was written.
                       MEMBER KRESS:  Yes, it is pretty cryptic,
           isn't it?
                       CHAIRMAN SHACK:  I mean, I had a rewrite
           of the paragraph that says,  "As now constituted, the
           user needs process may lead to an overemphasis on
           short-term work to support immediate needs and not
           result in adequate support for research needed to
           improve line organization capabilities."
                       MEMBER KRESS:  Is that a rewrite of the
           first paragraph?
                       CHAIRMAN SHACK:  Yes, that's a rewrite of
           that first paragraph.
                       MEMBER WALLIS:  You need something like
                       MEMBER KRESS:  Yes, that sounds pretty
                       MEMBER WALLIS:  I would support that and
           keep the first paragraph.  I'd support that.  And then
           the second paragraph I'm not sure we need that because
           they've already said that in the sentence that you
           added earlier.
                       MEMBER KRESS:  I would go along with both
           of those suggestions, Bill's rewrite of the first
           paragraph and --
                       MEMBER WALLIS:  And removing the second
           one on page 5?
                       MEMBER KRESS:  Yes.
                       MEMBER WALLIS:  Okay.  So, Bill, are you
           going to --
                       CHAIRMAN SHACK:  I'll give you some words,
           and you can figure out how to work them in.
                       MEMBER APOSTOLAKIS:  So you all agree with
           the third bullet here on this page, too?
                       MEMBER KRESS:  Oh, yes, that's another
                       MEMBER APOSTOLAKIS:  That was the ACRS
                       CHAIRMAN SHACK:  Well, I think we did try
           to consider that.
                       MEMBER APOSTOLAKIS:  Some place.
                       CHAIRMAN SHACK:  Some place.
                       MEMBER APOSTOLAKIS:  Not really -- it was
           not a uniform --
                       CHAIRMAN SHACK:  Nothing is ever uniform. 
           We have no criteria, George, no process.  We --
                       MEMBER KRESS:  No privatization. 
                       CHAIRMAN SHACK:  In fact, I had a
           paragraph if you'll look on the back of that, that
           says we -- can you give me that thing back?
                       MEMBER KRESS:  No.
                       CHAIRMAN SHACK:  I was going to put --
           following the three bullets, I was going to add
           something like, "In previous reports, we have argued
           that processes and criteria need to be developed to
           address such questions.  These have not been
           developed, and our current assessment is based on our
           own intuitive judgments."
                       Get into the Jocelyn-Graham job there.
                       MEMBER WALLIS:  I'd like to remove the
                       MEMBER APOSTOLAKIS:  Isn't it true that
           the whole risk-informed revision of the regulations
           really should be done by the licensees?  Who is
           benefitting from all of that?  Why do we have to do
                       MEMBER KRESS:  What did you say?
                       MEMBER APOSTOLAKIS:  Yes.  Why do we have
           to do it?  Why do we have to develop performance
                       MEMBER KRESS:  That's the job of the
                       MEMBER APOSTOLAKIS:  Why?  Who is
           benefitting from it?  I would argue that the licensees
           are benefitting and we --
                       CHAIRMAN SHACK:  We all benefit, George. 
           Benefit is not -- benefit is not the criteria.  That
           may be one of the elements of the thing.
                       MEMBER APOSTOLAKIS:  I don't know.  Is
           this work that needs to be done independently by the
           NRC?  Why is the revised oversight process something
           that we need to do?  They should propose all -- we
           review and approve.
                       CHAIRMAN SHACK:  That's why we need
           criteria and judgment for doing that.
                       MEMBER APOSTOLAKIS:  But that's not what
           it says.  It says that we actually use this.  
                       CHAIRMAN SHACK:  We tried to think our way
           through that based on our own judgment of when things
           needed to be done independently, and when we could
           just review the license --
                       MEMBER APOSTOLAKIS:  I think it was done
           in a very awkward way.
                       CHAIRMAN SHACK:  Of course.  Of course it
                       MEMBER APOSTOLAKIS:  We could put it front
           up here that -- I mean, I understand the first two
           bullets.  I mean, that we really did.  
                       MEMBER KRESS:  I think we've exceeded our
           one hour now.  So we can put it on the agenda --
                       MEMBER WALLIS:  Well, I do want to make
           some resolution about this question of by what
           criteria is this decided.
                       MEMBER APOSTOLAKIS:  Yes.  And that is
           something that bothers me, too.  I mean, the only
           thing we didn't put are those little angels around the
                       MEMBER KRESS:  Well, I think we would just
           indent it and not bold it.
                       MEMBER APOSTOLAKIS:  Huh?
                       MEMBER KRESS:  I think we would just
           indent it and not bold it and --
                       CHAIRMAN SHACK:  We already have it as one
           of the three bullets.  Why repeat it again?  Is sort
           of my theory.  You know, it's the same as this -- this
           work that needs to be done independently by the NRC
           rather than depending on information supplied by the
           licensee.  We've said it once.  We don't have to say
           it again.
                       MEMBER WALLIS:  Well, it's said again in
           response to this tension and competition.  I want to
                       CHAIRMAN SHACK:  Well, it's mentioned in
                       MEMBER WALLIS:  Why don't we black that
           whole thing about tension and competition?
                       MEMBER APOSTOLAKIS:  Although the
           identification?  This paragraph?  This paragraph?
                       MEMBER KRESS:  I might be in favor of
           that, particularly because there is something in the
           wind and we may want to add some more to this in --
                       MEMBER APOSTOLAKIS:  You're talking about
           the paragraph that starts, "Although there are" --
                       MEMBER KRESS:  Yes.
                       MEMBER APOSTOLAKIS:  Oh, that would make
           me very happy to take that out.
                       MEMBER WALLIS:  That until the end or the
           whole thing?
                       MEMBER APOSTOLAKIS:  Until the end, the
           present end.
                       MEMBER WALLIS:  The present.
                       MEMBER APOSTOLAKIS:  There would be
           another end.
                       MEMBER WALLIS:  There would be another
                       MEMBER APOSTOLAKIS:  Yes.
                       MEMBER WALLIS:  You're rewriting the end
           of the story?
                       MEMBER APOSTOLAKIS:  Shall we move on now
           and --
                       CHAIRMAN SHACK:  We have to move on now. 
           We have --
                       MEMBER APOSTOLAKIS:  I think we have to
           take action here and vote.  But the thought occurred
           to us earlier that perhaps we should add a few
           paragraphs to this as to where the agency -- what are
           the challenges in the future, in particular with new
           reactors.  We have some of that in Roman 3, but we
           should move it up maybe from last year.  
                       So what I would propose is that Tom and
           Dana -- Dana will be back on Monday -- add a few
           paragraphs and circulate them by e-mail, but we take
           a vote today, subject to that condition. 
                       Tom, is that correct?
                       MEMBER KRESS:  Yes.  I was under --
                       MEMBER WALLIS:  I think it would be very
           appropriate if we can do it well.  I think it should
           be in this report.  We're not going to --
                       MEMBER APOSTOLAKIS:   Okay.  So that's why
           we are assigning Tom to do it.
                       MEMBER KRESS:  It says I have to do it
                       MEMBER APOSTOLAKIS:  Yes.
                       MEMBER KRESS:  I didn't agree to that.
                       MEMBER APOSTOLAKIS:  I move that this
           report be accepted by the committee, subject to this
           condition that Dr. Kress will supply a few paragraphs
           to be added to the introduction regarding future
                       MEMBER BONACA:  And the last paragraph? 
           The introduction is scratched?
                       MEMBER APOSTOLAKIS:  That has been a --
                       MEMBER KRESS:  And I also met something
           that -- if you'll let me raise this with --
                       MEMBER APOSTOLAKIS:  That's part of the
                       CHAIRMAN SHACK:  Yes.  Dr. Kress has full
           power to do the cleanup work.
                       MEMBER KRESS:  Okay.  Good.
                       CHAIRMAN SHACK:  He's the cleanup man.
                       MEMBER APOSTOLAKIS:  Yes. 
                       CHAIRMAN SHACK:  Second.
                       MEMBER APOSTOLAKIS:  So there is a motion
           on the table and it has been seconded.  Any
           discussion?  Hearing none, those in favor of the
           motion raise your hand, please.  The research report
           is approved.
                       CHAIRMAN SHACK:  We're running a little
           bit late.  I think I still want to take a five-minute
                       MEMBER APOSTOLAKIS:  Yes.  Maybe we can
           shorten the lunch break.  Okay?  So we will be back
           when, at quarter of?
                       CHAIRMAN SHACK:  Quarter of.
                                   (Whereupon, the proceedings in the
                       foregoing matter went off the record at
                       9:36 a.m. and went back on the record at
                       9:45 a.m.)
                       CHAIRMAN SHACK:  We'd like to come to
           order now and begin our discussion of the 50.46.  And
           I believe we'll start with the industry presentation
           by Mr. Heymer, assorted support from a wide variety of
                       MR. HEYMER:  Good morning.  My name is
           Adrian Heymer.  I'm a project manager at NEI dealing
           with risk-informed regulation under Tony Petrangelo,
           who's our director, and I've been following the option
           three as well as some of the option two activities.
                       This morning what we're going to talk to
           you about is 50.46, and specifically what we believe
           the most important element to look at in 50.46.  And
           the one with the highest priority from a safety
           enhancement as well as a resource benefit is
           redefining the large break LOCA.
                       And I have with me here Lewis Ward from
           Southern Nuclear; Bob Osterrieder, Westinghouse Owners
           Group; Dave Bajumpaa, Millstone and the CEOG; and
           Terry Rieck from Excelon and representing the BWR
           Owners Groups.
                       We did have another representative from
           the B&W Owners Group, but something happened and he
           couldn't make it this morning.  Otherwise, we would
           have had the complete spectrum of the owners groups
                       And I think one of the messages we want to
           provide today, that this is an industry-wide activity. 
           The owners groups are on board, and I'm going to go
           over some of those issues and the industry structure
           and background as we move forward with this
                       So what we are really focusing on today is
           redefining the large break LOCA.  I will go over some
           background information how we got here and the general
           approach that the industry sees to improving this
           aspect of the regulation.  Then, the Westinghouse
           Owners Group will talk about a specific approach and
           some of their activities.
                       And then we'll have an example from the
           CEOG of what we call an application, what flows from
           redefining the large break LOCA to give you an idea of
           where the benefits are, and then Terry Rieck will say
           a few words on behalf of the BWR Owners Group.
                       I guess where we started off on risk-
           inform in the regulations was several years ago with
           SECY98-300, and at that time we were using this slide
           of what we believe is the important aspect of risk-
           informing NRC technical requirements, which was the
           improved efficiency and effectiveness of the NRC
           regulatory regime, to provide an increased focus on
           those issues that are safety significant while
           reducing unnecessary burden.
                       And that's the sort of fundamental element
           that we've looked at as we've moved forward.  And,
           obviously, to do that, you've got to look just not at
           the regulations but also at the guidance documents and
           at the industry codes and standards activities.
                       MEMBER WALLIS:  Well, there's another one
           of their objectives which is maintain safety.
                       MR. HEYMER:  Well, yes, but I --
                       MEMBER WALLIS:  Remember, that's one of
           the constraints.
                       MR. HEYMER:  Yes.  Yes.  I mean,
           increasing the focus on safety-significant issues
           should -- we believe should enhance safety.
                       And I guess as we went through this,
           following the Commission's SRM on 98-300, we went
           through and we looked at the technical requirements
           and we came up with a list, and there was an NRC
           workshop and we discussed some of those things with
           the NRC.  And we went out to the industry with a
           survey, and we included the list of regulations but we
           said, "What do you, the industry, think that we should
           focus on to improve our focus, focus on the safety-
           significant issues, and provide some benefit?"
                       And we got a list back from the industry,
           and we provided that list to -- the results of that
           survey to the Commission in January of 2000.  And in
           that, there were three specific areas.  One was -- the
           first priority was focus your activities on finishing
           what you've already started, which was things like the
           oversight process, fire protection, and the technical
           specifications, and then look at 50.46 and 50.44.
                       And the reason why they put 50.44 up there
           was that they felt with the amount of work that had
           gone on on 50.44 that was something that we could move
           forward fairly expeditiously.  But on 50.46, there was
           a number of issues why we came up with 50.46, and it
           just wasn't really associated with financial issues.
                       The initial 50.46, it has a large number
           of tentacles that go out.  Throughout the regulations,
           there's a number of issues that are linked to 50.46,
           and it was felt that if we could identify some of the
           items that perhaps don't have the same degree -- high
           degree of safety significance and where we perhaps
           could better focus our activities, we could make
           improvements both in safety and in -- and in the
           financial profile of the plant by looking at 50.46.
                       MEMBER WALLIS:  Are you going to enhance
           safety as well as try to reduce burden by removing the
           focus on low-risk significant events, but you can
           actually also look at the other side of the coin, that
           there are other things that are more important where
           you can enhance safety?
                       MR. HEYMER:  Other things that are more
           important that we should place greater emphasis and
           resources --
                       MEMBER WALLIS:  There's going to be a
           tradeoff.  It's not going to be all just reducing
           burden.  It's going to be actually --
                       MR. HEYMER:  Well, as has been said on
           many occasions, there's two sides to this equation,
           and we accept that.  And if there's things that come
           up that are required for safety --
                       MEMBER WALLIS:  I think for public
           reassurance, there's sort of -- there's a big drama
           associated with the large break LOCA.  And if you sort
           of want to -- not that the agency should back off on
           that.  There's going to be some good arguments that
           your -- because now your attention is focused on
           something else, you are actually improving safety. 
           Otherwise, it looks as if you're -- the agency is just
           backing off.  I don't think that's very good for
           public confidence.
                       MR. HEYMER:  No.  And I think that's the
           reason why we're couching it the way we do.  And I
           think if you look at the -- the large break LOCA, if
           you just look at some of the studies that have been
           done out there, it is a relatively low probability
                       And if you take that on as, we believe,
           negligible public risk, and -- and but we're not
           intending to sort of just throw everything away
           associated with that.  I think we've developed,
           through risk-informed ISI, a much better process of
           looking at what inspections we need to do on those
           activities.  We still have detection.  We're still
           going to carry out inspections in that regard.
                       Now, as I said, the effect from a safety
           perspective associated with redefining the large break
           LOCA is -- we think is very significant.  As I said,
           it's an essential element in the regulatory structure. 
           And if you can redefine what the break size is, then
           the follow-on activities and your resources can be
           adjusted to focus on the more probable activities and
           those matters that are of safety significance.
                       And you'll see as we go through the
           presentations here today some of the activities that
           we get involved in link specifically to the large
           break LOCA, which if you take a more realistic
           approach to it we wouldn't have to be expending
           resources in that area.  So we hope to --
                       MEMBER WALLIS:  The fact that it is a
           central and controlling element, the way you've
           identified it here, means that in the past it was
           assessed as being important enough to have this role
           of being a central and important controlling element.
                       MR. HEYMER:  That is true.  But I think as
           -- and as we started out the regulations, there was a
           very conservative approach to say it's the double-
           ended guillotine break of the largest pipe.  And
           that's why we're emphasizing it's the redefining. 
           It's not the elimination of the large break LOCA. 
           We're redefining it.
                       MEMBER WALLIS:  So it's not, though, as if
           you're asking to simply redefine something of low-risk
           significance.  You're asking to redefine something
           which is a central and controlling element.  It's a
           major step.
                       MR. HEYMER:  It is a significant step. 
           But on the other hand, it has, we believe, significant
           benefit, both in terms of safety and finance.  Having
           determined it was 50.46 and perhaps it should be
           redefining large break LOCA, Westinghouse Owners Group
           already had an activity underway and have already done
           some extensive evaluations of redefining the large
                       And through those activities, we pulled
           the other owners groups together, and I think we've
           developed over the past 18 months sort of an industry
           approach, which I'll go into and which we've described
           in several meetings and workshops with the NRC staff
           as we've moved through and discussed the options of
           what to look at first, because 50.46 is a very large
           and complex regulation.  And we think if you're going
           to look at 50.46 you need to focus on what is really
           going to provide the benefit, and to us that is
           redefining the large break LOCA.
                       We've listed some of the -- some of the
           safety enhancements that we see from here.  I think on
           a number of unnecessary plant transients it gets back
           into how many times you can sort of begin to run up
           against the limits in the technical specifications
           that are linked back to the large break LOCA.  And so
           if you don't have to have a power train, you shouldn't
           be imposing one, not only from a financial
           perspective, but also from a plant safety perspective.
                       MEMBER WALLIS:  Can you explain that a bit
           more?  You say "unnecessary plant transients."  You
           mean deliberate transients.  You have to run the plant
           through some transient under the regulations.
                       MR. HEYMER:  Because of the regulation.
                       MEMBER WALLIS:  It means you have to test
           things or something?
                       MR. HEYMER:  On a testings or come down in
           power or shut down or come to a halt -- shut down
           while you fix something, or even go to a cold
           shutdown.  So the number of times you exercise -- move
           through those -- those plant states --
                       MEMBER WALLIS:  Is all motivated because
           of the large break LOCA?
                       MR. HEYMER:  Or linked to requirements and
           technical specifications or other -- that are linked
           into the large break LOCA.
                       MEMBER WALLIS:  It would be nice if you
           could have some numbers associated with that, and let
           us know what's the number and the cost or something.
                       MR. HEYMER:  Yes, we can get back in
           subsequent presentations on that.
                       MR. OSTERRIEDER:  We do have a couple of
           examples later in the presentation.
                       MR. HEYMER:  Yes.  We'll speak to that.
                       We speak here about improved worker safety
           profile, and I guess the potential to rebalance the
           ECCS system so that we -- we focus on more probable
           events, such as the small break LOCA or the breaks of
           a smaller size, intermediate and small, I think that
           once you come up with whatever the new break size
           would be and you start running that through the PRA,
           your safety assessments and your PRA assessments
           become even more meaningful and just improves the
           general process.  So --
                       MEMBER WALLIS:  So you're claiming that
           because of the focus on large break LOCA we have some
           requirements for ECCS that may actually be detrimental
           in the case of other kinds of LOCA?
                       MR. WARD:  Yes, sir.
                       MEMBER WALLIS:  Yes?
                       MR. WARD:  The particular example that
           we've discussed several times is the balancing of the
           ECCS system so that when you have a large break LOCA
           all of the water does not go to the broken loop, that
           there is a certain amount of it that goes into the
           intact loops and then goes to the core.  And those --
           we put orifices in typically to do that and balance
           them to prevent runout on the pumps in that condition.
                       But what that does is if we had, for
           example, a smaller loss of coolant accident or a small
           leak, that -- those orifices are still in place and it
           throttles back the amount of water that would be
           delivered to the loops in that condition.
                       If we were designed to some intermediate-
           sized break, then you could decide -- you could open
           up the orifices, provide more flow to the core for the
           small break than we do now, because you would not have
           the pump runout concerns on the high end.  That's one
           example that we thought about.
                       MR. HEYMER:  Our overall approach for
           redefining the large break LOCA takes into account
           that we have varying designs out there and varying
           designs -- we have boilers, we have pressurized water
           reactors, we have CEABB plants, we have Westinghouse
           plants, we have B&W plants.
                       And, therefore, what our approach is is a
           relatively straightforward rule change.  At the
           moment, the regulations say that you will analyze with
           the double-ended guillotine break of the largest pipe. 
           And we think the add-on would be you would just add a
           phrase "or alternative break sites as approved by the
                       And to the extent of the rule change,
           there would be some other conforming changes where in
           other parts of the regulations, perhaps the general
           design criteria, you'd define what a loss of coolant
           accident is, so that there would be some conforming
           changes there.
                       And having done that, and having started
           to progress with the rulemaking, each owners group
           would develop and submit what they believe would be
           the justification for redefining the break size for
           their particular designs.  And that would be an owners
           group specific activity.
                       But just redefining the break size alone
           doesn't really get you there, and so you start looking
           at applications.  And so once there is a good
           understanding on what the break size would be as we
           begin to focus down and reach an understanding with
           the staff on what the break size would be, you can
           then start looking at the specific applications, be it
           diesel generator start times, balancing ECCS that we
           spoke about.
                       And they would be done, again, on an
           owners group basis, generic as much as we could for
           each owners group, so that when the licensee came
           along they could just submit a license amendment based
           on the topical reports that have already been approved
           by the staff.  And we think that would be the most
           efficient use of resources of moving through this.
                       So it's really simple that the initial
           step is -- is to move forward with a rule change that
           would say -- as I've said, allow an alternative break
           site as approved by the Commission, but don't define
           that break size and leave that from the -- for the
           technical interactions between the owners group and
           the staff to come to some conclusion on what that
           break size is.
                       MEMBER WALLIS:  Wouldn't you still have to
           analyze the large break LOCA anyway in order to show
           that it's not significant?  You have to do something
           with it.  You can't just ignore it.
                       MR. HEYMER:  Well, no, you just don't
           ignore it.  That's some of the issues that we're going
           to be --
                       MEMBER WALLIS:  But you'd still have to do
           an analysis and convince the Commission that this
           break is not important or something.
                       MR. HEYMER:  Well, as we --
                       MEMBER WALLIS:  Wouldn't that just be a
           risk analysis?  Or would that be a technical analysis?
                       MR. HEYMER:  Well, we will continue --
                       MEMBER APOSTOLAKIS:  Mechanistic, you
                       MR. OSTERRIEDER:  We would continue with
           large break LOCA in the risk models for the plants. 
           But, you know, so that -- it wouldn't be taken out, so
                       MEMBER WALLIS:  So it would still be in
           the risk models, but it wouldn't be in the sort of
           technical requirements.
                       MR. OSTERRIEDER:  Right.  It's like other
           things in the risk models that aren't necessarily part
           of your design basis.
                       MEMBER WALLIS:  Yes.  But in order to do
           the risk model, you have to do a thermal-hydraulic
           type analysis and everything.  You have to look at
           consequences and all that.
                       MR. OSTERRIEDER:  Right.  You need to do
           appropriate success criteria analysis.
                       MEMBER WALLIS:  So it wouldn't go away. 
           You'd have --
                       MR. OSTERRIEDER:  That's correct.
                       MEMBER SIEBER:  Well, it's an interesting
           thing.  If you enlarge the size of the orifice, which
           you said was going to be an advantage to having a
           smaller break size, then if you actually did have the
           large break the pumps would run out, and the outcome
           would be different than you currently have now.  So
           the risk numbers and consequences would go up.  Is
           that not true?
                       MR. OSTERRIEDER:  Right.  Yes, they
           would --
                       MEMBER SIEBER:  In other words, you could
           not handle the --
                       MR. OSTERRIEDER:  Right.  The risk of that
           occurring would be assessed into the plant's risk
           model, since it --
                       MEMBER SIEBER:  That's right.  But if it
           did occur, whatever the probability, the ECCS couldn't
           handle it.
                       MR. OSTERRIEDER:  That's right.
                       MEMBER SIEBER:  Under those circumstances.
                       MR. OSTERRIEDER:  Well, we'd assess with
           the success criteria -- certainly more likely less
           success probability, certainly.
                       MR. HEYMER:  And as we get into the
           discussions here, I think you'll also hear that our
           emphasis isn't necessarily doing extensive
           modifications based on this, but allowing for
           operational margin to -- for us to operate with that
           margin so you don't have to get involved in some of
           these evaluations and activities that Dave here will
           talk about from the CE perspective -- so perhaps
           ultimately the sink calculations, containment, heat
                       So we're not talking about ripping out
           pumps and replacing pumps.  What we're talking about
           is, okay, we don't have to -- perhaps the engineering
           specification is going to be the same, but the actual
           licensing and technical specification may be a little
           bit different.
                       MEMBER KRESS:  Why shouldn't I view this
           from the perspective of Reg. Guide 1.174 and say
           here's a suggested change in the licensing basis for
           lots of plants, not just one.  That will result in
           these changes to specific plants, the listed changes. 
           I suspect you have those.  And then that will change
           the risk status of each of these plants by this much,
           and looking at the guides in 1.174 say whether that's
           acceptable or not.  Why isn't -- I don't see a
           perspective -- well, it seems like we're viewing this
           strictly from the design basis accident space and not
                       MR. HEYMER:  Well, I mean, the initial
           step coming out of this isn't to say, well, we want to
           redefine the large break LOCA because we want to have
           a different pump size there.  But on the other hand,
           if somebody then wanted to go and implement a
           modification, they would then use the 1.174 as the
           guideline.  And the guideline and the baseline for the
           plant would be adjusted based on whatever the new
           break size came out to be.
                       So, I mean, I think what you're saying is
           that, yes, okay, once you've redefined it, you may
           some stage down the road want to perform a
           modification, and, yes, you would use 1.174.
                       MEMBER KRESS:  I see.  So that would come
           in at the point where the plant decided -- a specific
           plant decided that --
                       MR. HEYMER:  Yes.
                       MEMBER KRESS:  -- take advantage of the
           new definition and make some changes.
                       MR. HEYMER:  That's right.  Within the
           confines of 1.174 and the new rule and the guidelines
           and the technical documents, but not as a direct --
                       MEMBER KRESS:  Why couldn't they do that
                       MR. OSTERRIEDER:  I think it's more simple
           than that.  We are planning to use the 1.174 framework
           and assess the risk significance of large break LOCA. 
           So I think the answer is simply, yes, we are intending
           to do what you're suggesting that we should be doing.
                       MEMBER KRESS:  Yes.
                       MR. OSTERRIEDER:  As you'll see it in my
           summary of what we've been able to do.  I think we're
           doing that.
                       MEMBER KRESS:  Maybe I should wait until
           we hear that.
                       MR. OSTERRIEDER:  Or tell me if we're not
           answering the question, certainly.
                       MEMBER WALLIS:  Adrian, you talk about
           alternative break size.  This is really in the old
           deterministic world where you have sort of specified
           things you have to consider.  But in a risk-informed
           world, you really ought to look at all break sizes,
           including large break LOCA.
                       MR. OSTERRIEDER:  We do.  And we will --
                       MEMBER WALLIS:  Make an assessment --
                       MR. OSTERRIEDER:  Yes, we do.
                       MEMBER WALLIS:  -- and if you change your
           orificing, then your consequences change and your risk
           assessment changes for all of them.
                       MR. OSTERRIEDER:  That's correct.
                       MEMBER WALLIS:  And you don't -- there's
           no real change.  You have to look at the complete
           spectrum of breaks.
                       MEMBER KRESS:  There's only a change if
           they make modifications to the plans and procedures.
                       MEMBER WALLIS:  Right.
                       MEMBER KRESS:  I think that's what you
           have to look at.
                       MEMBER BONACA:  Probably to do that I
           think they only leave -- they can assign a very low
           probability to that event.  So, no, that -- so they
           are going to consider that.
                       MEMBER KRESS:  Well, that's almost
           irrelevant.  I think what the relevant thing is is
           what modifications and what changes will result from
           the change in the definition.
                       MEMBER BONACA:  Yes.
                       MEMBER KRESS:  It doesn't matter how low
           the probability is.  It's what --
                       MEMBER BONACA:  What I'm saying is that
           they're not going to eliminate the possibility. 
           They're going to consider it still.  They're only
           saying that the likelihood of the large break LOCA,
           the way he's --
                       MEMBER KRESS:  It may still not contribute
           much to risk --
                       MEMBER BONACA:  That's right.  They're
           saying --
                       MEMBER KRESS:  -- for that sequence, but
           the changes to the plant that result from the change
           -- you see, the tentacles of design basis accident go
           beyond a specific sequence you look at or --
                       MEMBER BONACA:  That's obvious.  But I'm
           saying that -- that they are not neglecting that. 
           That's all I'm saying.  I'm only saying that since it
           is assuming low probability most likely, then it
           should not be the design basis event you are designing
           it for.  And then there are tentacles we have to look
           at.  I agree with that.
                       MR. HEYMER:  And, in fact, what we're
           getting into here is some of the more detailed
           discussions, and I think it's a good point at which we
           can hand over to the Westinghouse group to get into
           some of the more specifics of the technical approach. 
           And I'll ask Lewis Ward to lead off on that.
                       MR. WARD:  Yes.  I'm Lewis Ward with the
           Southern Nuclear Operating Company of Bogle, Farley
           and Hatch.  I'm the Chairman of the Westinghouse Large
           Break LOCA working group.
                       This project started off within the
           Westinghouse Owners Group a little over two years ago. 
           We had an invitation from Commissioner Diaz to each
           identify the most single important program that we
           could work on that would help our fleet of plants. 
           And the WOG identified large break LOCA elimination,
           I believe is the way it was phrased at that time.
                       Shortly after that we put together a
           steering committee to start through the process of
           following up with that letter to Commissioner Diaz,
           and really deciding what approach we would take on
           going about a rule change.  We looked at the rules
           themselves as very simple.  There's about three places
           in Appendix K and Appendix -- in 50.46 and Appendix A
           that, you know, we need one sentence basically.
                       But as we realized right off, there is
           much, much more to it than that.  There are numerous
           Reg. Guides and other documents below that that spin
           off from that.  So we internally worked for about a
           year to try to put together a framework within our
           owners group on how we would get our owners to fund
           such a program, realizing it was going to take a big
           commitment of resources on our part to even launch off
           into that.
                       About a year ago we also got all three of
           the other owners group involved with us, and NEI
           started doing a coordination role with us.  And right
           now, all four of the owners groups representing all of
           the plants in this country are on board with us on
           this project.
                       What we have done is tried to think
           through many of the questions that you're asking and
           -- and put some thought behind how we would go about
           addressing those issues.  
                       One of the program approaches that we've
           put together in our framework is that we really need
           an implementation plan that would be exactly what
           you're asking about, so that, you know, once we get a
           rule change, what do we -- what do I as a licensee --
           how do I go about implementing a particular change on
           a particular system or component or design basis with
           my plant?
                       And the approach that we are looking at is
           to come up with an implementation guideline that is an
           industry-wide guideline.  Each of our owners groups
           feels like, you know, we would put together a
           guideline, have it reviewed and agreed to by the
           staff, and possibly endorsed by a Reg. Guide, and
           probably have a predefined list of the things that we
           could go about doing once we got the rule change.
                       Now, there may be many, many other things
           that we did not think about as we went through that
           we'd then follow up with the normal licensing process,
           either under 1.174 tech spec submittals and that kind
           of thing.
                       That's the general approach we've been
           working on.  Over the last year, we have had numerous
           internal meetings with all of the owners groups to get
           this plan more or less laid out.  We've started
           gathering data to support the specific analysis for
           the Westinghouse fleet.  And we have proceeded
           forward, and we -- we've kept the staff fully
                       I believe we've met six times with the
           staff over the period of the last year or two, to lay
           out our game plan and to get staff's feedback.
                       The safety benefits -- I'll go over part
           of this and Bob will go over part of it.  The safety
           benefit -- I think all of us recognize that safety has
           to be our first priority.  We, as owners, investors,
           and operators, and citizens who live next door to
           nuclear power plants, do not -- did not want to go
           down any path that we did not feel like was right from
           safety.  And so that has been our first focus.  
                       We believe that doing this process will
           allow us to put our limited resources on other
           activities that have greater risk significance.  Right
           now, we spend a lot of engineering time, we spend our
           highest level of engineering expertise on areas such
           as large break LOCA.  Our training staff spent a lot
           of time on large break LOCA.  If you're a licensed
           operator, which I had an SRO license at Farley, you
           can expect a large break LOCA on one of your requal
           drills on the simulator.  
                       As we've seen an event within the last
           year not having to do with LOCA, there are more subtle
           accidents that are more realistic that the operators
           need to learn to deal with more than the "here's the
           big one," "I know how to deal with this one," and we
           go on.
                       Surveillance testing -- we do a tremendous
           amount of surveillance testing for tech spec
           surveillance requirements that are directly hinged to
           large break LOCA, such things as accumulator level
           transmitters in containment, very, very tight
           tolerance bands, extremely time-consuming dose
           activities that would go away or be extensively
                       There's a considerable amount of
           maintenance.  We do fast starts on diesel generators
           every month or more often.  It puts wear and tear on
           diesel generators; we have to tear them down, overhaul
           them, and keep them in shape so they will pass the
           surveillance over and over again in the event that
           they are needed for the LOCA with a station blackout.
                       There are design issues that we have to
           resolve.  We work on design issues every day.  There's
           a current issue on containment sumps that all of you
           are aware of.  There are other issues that we have to
           deal with on a design basis every day in the plants to
           try to get resolved for this very unlikely event.
                       MEMBER KRESS:  Now, if I had two
           categories and one of them was safety benefits and
           burden reduction, it seems to me like most of those
           things you just talked about would fall under burden
                       MR. WARD:  They are burden reductions
           which, recognizing we have limited resources in terms
           of technical expertise --
                       MEMBER KRESS:  Is this a zero-sum
           activity?  So those resources -- the money and
           activities actually go into other things?
                       MR. WARD:  Yes.
                       MEMBER KRESS:  You save money that way.
                       MR. WARD:  No.  We don't -- I don't
           envision any of us laying any people off.  I think it
           would allow the people that are doing these activities
           to focus on something else.
                       MEMBER WALLIS:  I think he's saying that
           the operators would be better trained if they were
           trained to face up to real events and not have so much
           emphasis on LOCAs.  Actually, the plant would be
           better.  It's not just reducing burden.  It's better
           use of people and resources.
                       MEMBER KRESS:  I'm not so sure that
           redefining the large break LOCA has anything to do
           with the training process.
                       MEMBER WALLIS:  Well, I think that's what
           you're saying is you have a lot of people spending
           time on something which is just very unlikely to
                       MR. WARD:  Yes, that's correct.  And that
           was my point.  
                       MEMBER KRESS:  You shouldn't do that.  I
           mean, I don't see that that has anything to do with
           this definition.
                       MEMBER BONACA:  But isn't the bigger issue
           that -- from what I've seen is that the requirements
           of the large break LOCA on equipment are forcing a
           very tight margin on equipment.  I mean, simply there
           isn't time on diesels to wait.  You have to start them
           and you have to test them cold.  And so that's because
           you have such a strict requirement coming from the
           largest demand, which is the LOCA.  
                       That's true of HVAC systems.  They would
           have to be reconfigured in -- with them in, like the
           clock or -- isn't that issue of marginality of the
           equipment that is really the bigger driving issue? 
           You're bumping limits, you're bumping the tech specs,
           you have to find out because you are so marginal in
           that your -- the demand is maximum for this, isn't it?
                       MR. WARD:  Yes, that's correct.  So when
           we hit one of those limits, the -- our expertise works
           on that problem, not something else.  And that's the
           -- it's a zero net sum, I think, but it's -- where do
           you want to put the focus?  On something that's most
           likely never going to happen or something that is
           likely to happen.
                       MEMBER BONACA:  Yes.  From my experience,
           I mean, the problem is always that the plant is just
           barely making those requirements of the LOCA. 
           Therefore, it's easy to bump into, you know -- the
           diesel start is 10 and a half seconds, and the diesel
           is not starting in -- it starts in 10.6 seconds.  And
           that one-tenth of a second is just killing you if you
           have to do all kinds of jumping around to show that
           you can come out.  That's really where I see a
           significant impact.  I mean, from the requirement you
           are making.  Okay?  Just the equipment barely makes it
                       MEMBER KRESS:  So that's one change.  And
           there must be a list of these changes.  And the
           question I have is:  do those particular changes have
           any significance in maintaining the risk profile of
           plants to an acceptable level?  Somehow I haven't seen
           that case made yet, but I --
                       MEMBER BONACA:  I agree totally with you. 
           That's my thought process, too.  I would like to see
           at some point in all these presentations the list of
           the benefits and what they mean.
                       MEMBER KRESS:  Yes.  You know, I --
                       MEMBER BONACA:  And then I could decide --
                       MEMBER KRESS:  Well, it's clear that there
           would be some benefits with this.  And it's not
           exactly as clear that the -- that this thing doesn't
           have safety significance.  But, you know, it looks --
           I mean, the implications is that it doesn't, but I
           haven't really seen the case made yet.  I've seen, you
           know, assertions to it.
                       MR. WARD:  There is a list of benefits on
           toward the back of the page that we'll get to in a
           little while, and there are many that are -- that's
           just a partial list.  But I think what we wrestled
           with for the qual was the -- it's going to take quite
           a bit of effort on all of our parts to work through
           this program to develop the list of benefits and the
           approach on how we could benefit or how we can achieve
           those benefits with the rule change.
                       And that's why we've been working real
           closely with the staff on a -- you know, before we go
           commit all of our resources and put together a 100
           percent complete package, and then no assurance that
           -- that anybody is going to listen to it, you know,
           that's why we've been having a continuing dialogue
           with the hopes of moving forward on that basis.
                       But we do have a list, and Bob will go
           over them a little while later.
                       Another point is the consistency within
           the regulations.  Right now, leak before break is an
           approved methodology for certain actions --
           elimination of whip restraints, baffle -- reactor
           vessel internal -- it's a baffle bolt issue.  So it's
           been recognized by the Commission for 15 years that
           this is approved technology for certain uses.
                       And it presents us a problem by having one
           set of requirements for one application and a
           different set of requirements for different
           applications.  And what we are proposing is something
           that would clean up that inconsistency within the
                       Okay.  Bob, I'm going to turn it over at
           this point to Bob Osterrieder with Westinghouse, who
           is our lead manager.
                       MR. OSTERRIEDER:  Okay.  What I'm going to
           do is try to briefly summarize what our approach is in
           redefining the large break LOCA, and then we'll move
           on, after I talk about that a little bit, to some of
           the example applications that you're asking about.
                       Essentially, you know, we view this as a
           risk-informed initiative based on SECY98-300, Option
           3, and as part of that we're envisioning this to be an
           optional implementation where you could return your
           current licensing basis in regard to large break LOCA.
                       Adrian already mentioned that there is
           essentially three key places where the definition of
           LOCA is in the regulations, that it has to be a
           double-ended -- if they analyze up to a double-ended
           rupture of the largest primary piping, and we're
           envisioning changing that in these three places --
           Appendix K, Appendix A, and 50.46.
                       What we intend to do is redefine the
           maximum size and the attendant consequences while
           maintaining an acceptable margin of safety.
                       MEMBER APOSTOLAKIS:  But let me understand
           here -- the issue -- the question was asked earlier
           regarding 1.174, and now we have Option 3.  I mean,
           how do these things play against each other? 
                       Tom, you raised the question of 1.174.  I
           mean -- yes, go ahead.  I'm sorry.
                       MR. OSTERRIEDER:  I was going to say,
           we're going to be -- you'll see on the next slide
           we're actually looking at 1.174.  That's just part of
           the Option 3 approach.  I think they're all --
                       MEMBER APOSTOLAKIS:  Okay.  Well, if you
           come to it later, we'll wait until then.
                       MEMBER KRESS:  One of the places where the
           double-ended rupture shows up is in the general -- in
           the design basis accident, the containment.  You know,
           that doesn't affect -- hey, guys, you're going to go
           in and weaken your containment just because of this
           change in rule.
                       But it might affect future plants if we
           did something like this.  You know, a future plant
           could have a new -- are we going to exempt
           containment, or are we going to keep that -- give the
           -- make a new design basis for containment?  Is that
                       MR. OSTERRIEDER:  Well, what we've
           discussed to date is, as you indicated, not changing
           the actual physical containment but allowing some
           operational flexibility.  You know, you may be able to
           change some --
                       MEMBER KRESS:  You can change your leak
           range measurement --
                       MR. OSTERRIEDER:  Yes.  And --
                       MEMBER KRESS:  -- for one thing.  I see
           where that --
                       MR. OSTERRIEDER:  Right.
                       MR. HEYMER:  The CE Owners Group is going
           to -- the specific application where they talk about
           containment -- and I think that they will be able to
           really get into that situation.  With regard to new
           plants, we think that Option 3 should be kept separate
           from new plants.  And if you're going to go forward
           with new plant regulations and thinking about a
           framework for the regulatory regime --
                       MEMBER KRESS:  Try to do --
                       MR. HEYMER:  -- you need --
                       MEMBER KRESS:  -- another -- Option 4
           maybe or --
                       MR. HEYMER:  You'll have a totally
           framework and you're going to start off with a clean
           sheet of paper and really -- really go through it.
                       MEMBER KRESS:  I agree with that.  An
           Option 4 type thing.
                       MR. HEYMER:  Yes.
                       MEMBER KRESS:  Okay.
                       MR. OSTERRIEDER:  Again, the approach
           we're looking at is on the technical justification
           slide.  We will be using risk-informed technology to
           show the low-risk significance of the large break
           LOCA.  Utilizing Reg. Guide 1.174, we're going to be
           assessing the likelihood and the consequences of large
           break LOCAs to demonstrate that they're of low-risk
           significance and that these --
                       MEMBER APOSTOLAKIS:  And, again, 1.174
           utilizes the current CDF and LERF, right?  I mean, and
           the delta CDF and delta LERF.  Are you going to do
           this in a generic way?  And if you do, what kind of
           CDF are you going to use?
                       MR. OSTERRIEDER:  We're doing some generic
           work.  Each of the owners groups is looking at the
           risk significance of large LOCA.  We, in fact, have
           calculated some new initiating event frequencies for
           large LOCA, but even if we hadn't what we are
           intending to do in assessing the risk significance is
           look at all of the plants, the importance of large
           break LOCA, and --
                       MEMBER APOSTOLAKIS:  For each plant.
                       MR. OSTERRIEDER:  For each plant.
                       MEMBER APOSTOLAKIS:  Oh.
                       MR. OSTERRIEDER:  And we're containing
           that in a -- at least for the Westinghouse Owners
           Group, we're going to put that into one risk
           significance document that's going to explain how risk
           significant is large break LOCA in terms of core
           damage frequency and large early release frequency,
           and then addressing the -- the five principles of
           1.174.  That's what our plan is, and we intend to
           submit that for review.
                       MEMBER KRESS:  Well, let me ask you a
           question about that.  I could envision that -- that
           this change would allow you to go to a higher leak
           rate from the containment, possibly, because, you
           know, you're holding the pressure down lower.  And so
           for you applying this -- the source term that you have
           to apply, you could end up with a lower leak rate.
                       That implies to me that for other
           accidents, other sequences, that it's possible, then,
           that in the -- if you shift now to the PRA, that the
           frequency which you exceed certain releases of
           activity in the low level for -- you don't break
           containment.  You don't have a LERF.  But you still
           have core damage of some sort.
                       Those frequencies are going to increase,
           although you wouldn't see that at all in CDF, and you
           wouldn't see it in LERF.  And it seems to me that
           those things are of interest at least.  They are to
           me.  And how would that be dealt with in a 1.174
                       MR. OSTERRIEDER:  Well, I'm not sure about
           in the 1.174 sense, but we will be looking at the
           effects of any plant changes.  If we do do a change to
           the leak rate parameters, then we need to assess does
           that affect the calculated dose rates for other events
           that use those parameters in the analysis.
                       MEMBER KRESS:  Yes.  But that would be in
           the deterministic space, in the Chapter 15 space.
                       MR. OSTERRIEDER:  Right.  It would --
                       MEMBER KRESS:  Which doesn't, you know --
           you have to meet those surely, but -- but it doesn't
           show up in 1.174 anywhere, which wouldn't -- you know,
           the only place it shows up in 1.174 is a little
           sentence that says, "You will also meet the rest of
           the requirements, the rest of the regulation."  
                       But I'm worried that CDF and LERF doesn't
           capture small releases and doesn't capture late
           releases and doesn't deal with things like injuries to
           workers and injuries to the population, that there are
           less deaths.  I worry about those things that it seems
           to me like 1.174 doesn't properly capture.
                       MEMBER SIEBER:  Well, there's other
           requirements besides 1.174.  You have 50.2 that has a
           dose-limited defense line, and 50.35, and other
           general design criteria which you have to meet anyway. 
           And that's in a deterministic and absolute sense.
                       MR. HEYMER:  Yes.  I mean, at the moment,
           we're just focusing on 50.46 and redefining the large
           break LOCA.  And I agree that those -- those
           requirements are still in place, and we would still
           have to show that we meet those requirements.
                       MEMBER SIEBER:  That's right.
                       MR. HEYMER:  And the same for OSHA and
           other worker safety requirements that -- that are
           there.  We have to meet those.  So we're not looking
           at changing those, and so that's what we would still
           be governed by, regardless of what you might be --
                       MEMBER KRESS:  Yes.  The problem I have is
           those other requirements are not necessarily risk-
           informed.  And we're trying now to go to a risk-
           informed process.
                       MR. OSTERRIEDER:  Okay. 
                       MEMBER KRESS:  But, anyway, that's a
           personal problem I have.  I don't want to --
                       MR. OSTERRIEDER:  One other --
                       MEMBER KRESS:  -- dwell on it.
                       MR. OSTERRIEDER:  One other point. 
           There's no guarantee that you can reduce your leak
           rate testing because a lot of plants are governed by
           steam line break pressures for --
                       MEMBER KRESS:  Yes, that's right.
                       MR. OSTERRIEDER:  You know, so if you have
           to look at the entire picture for your plant and
           decide --
                       MEMBER KRESS:  So it'll be plant-specific.
                       MR. OSTERRIEDER:  Sure.  You need to
           holistically evaluate any potential plant changes.
                       Okay.  The second part of -- after we
           evaluate the risk significance, and demonstrate how
           risk significant the event is, then we'll also be
           relying on a deterministic piece of looking at leak
           before break analysis to justify the break size that
           we'll be submitting to the staff for approval as the
           new maximum break size.
                       And then we'd have to do further analysis
           to evaluate real plant changes as a result of the rule
                       MEMBER KRESS:  That's what I want to see.
                       MR. OSTERRIEDER:  And just to kind of
           follow up on what we mentioned before, we're already
           allowed to use leak before break and not analyze
           certain aspects of the plant for the full double-ended
           guillotine break.  And that is, GDC4 allows for
           application of leak before break to high energy piping
           to -- involved with the evaluation of the dynamic
                       And a number of plants have applied this
           for main coolant piping, pressurizer surge line, and
           a few other examples here.
                       MEMBER KRESS:  Has leak before break been
           approved for the big-sized pipes that we're talking
                       MR. OSTERRIEDER:  We've had leak before
           break approved for certain applications down to and
           including I believe we even have a six-inch approved
           for the plants.
                       MEMBER SIEBER:  But that's just for
           Westinghouse, the combustion plants, right, and B&W? 
           But not for --
                       MR. OSTERRIEDER:  Well, it's not a generic
           approval.  Each plant may have different --
                       MEMBER SIEBER:  Right.  Gets it on its
           own, right.
                       MR. OSTERRIEDER:  Right.  And submitted
           their own, you know, work and gotten it approved for
           that particular plant.
                       Okay.  What we intend to do is take the
           existing leak before break work that's already been
           accepted for certain applications and extend that to
           other applications beyond the dynamic effects.  And
           what we have envisioned was using the same methodology
           that was used in those cases.
                       And then what we would do, depending on
           the maximum size that the -- that you're looking to
           put as the largest LOCA size you must analyze, we'd
           perform -- potentially perform leak before break on
           additional lines, if you hadn't already covered those
           lines with your existing leak before break work.
                       And we're intending to consolidate and
           make more efficient the review by justifying one
           maximum size, at least for the owners -- Westinghouse
           Owners Group, and each owners group is going to
           decide, you know, how do they want to approach that.
                       MEMBER KRESS:  I guess implied in that
           approach, then, is if you can just -- if you can
           invoke leak before break, that that renders the
           frequency of failure of those pipes that you invoke it
           for to a low enough value that they wouldn't show up
           significantly in the risk profile?  Is that the
                       MR. OSTERRIEDER:  Not -- I believe it's
           slightly different than that.  I believe it's more the
           -- the leak before break is a -- a demonstration that
           you will detect this before you get large LOCAs, and
           the large LOCA may never --
                       MEMBER KRESS:  Plus, you reduce the
           frequency way down, because you're going to detect it
           in the --
                       MR. OSTERRIEDER:  Well, because it's based
           on frequencies and propagation of cracks and to
           potential leaks, and then the leak detection
           capabilities of the plant.  But the frequency itself
           that you would use in your PRA, we have recalculated
           frequencies using fracture mechanics.  But you
           wouldn't have to do that.
                       I mean, the main purpose of the leak
           before break analysis is to support the idea that we
           show that large LOCAs are not risk significant, and
           then we show that we have some mechanism to evaluate
           the actual plant and that we will not have a large
           break before you would detect it.
                       It sounds like I'm not answering your
                       MEMBER KRESS:  Well, it sounds like you
           answered it -- yes, to what I said, but I guess --
                       CHAIRMAN SHACK:  But I think you will end
           up essentially calculating a frequency of rupture as
           a function of pipe -- that will -- that will go into
           your PRA evaluations of delta CDF and delta LERF.
                       MEMBER KRESS:  My question is if that
           number is below, say, 10-6, then you say, "Well, we
           won't worry about that pipe."  If it gets above --
           around 10-6, we'll say, "Okay.  That may be the size
           we're dealing with for large break LOCA."  I was
           wondering if that was the rationale.
                       MR. OSTERRIEDER:  Well, that's part of the
           approach that we've done in the Westinghouse Owners
           Group and we're going to be submitting is looking at
           the probability of all these different pipes in the
           plant leaking above a certain amount, which, you know,
           that will define the size.  And we're looking at all
           the pipes and, yes, that's exactly what we're doing.
                       MEMBER KRESS:  Okay.  That was the nature
           of my question.
                       MR. OSTERRIEDER:  Okay.  Again, one aspect
           that, you know, we've talked about, if -- if you
           change your maximum LOCA break size, the question has
           come up, "Do we need to identify other events that we
           possibly don't analyze now?"  And we believe that you
           should currently be analyzing all of the significant
           events for different plant systems, but we do need to
           make sure if we lower the maximum size that we haven't
           in the past said we don't need to analyze a certain
           event because it's bounded by this.  
                       We need to make sure that we don't now
           have that resurface, and then we -- you know, so we
           may end up having to do additional analysis.  That
           we're looking to do that as part of our comprehensive
                       Adrian already mentioned that following
           the rule change plant-specific changes to the maximum
           size would require a submittal and approval of the
           NRC.  So you'd start with the rule change, allowing
           you to change the maximum, and then you would have to
           get approval from the NRC to --
                       MEMBER KRESS:  So the rule wouldn't
           specify the size.
                       MR. OSTERRIEDER:  That's correct.  We're
           envisioning a broad rule, and each owners group would
           need to decide on what size is appropriate based on
           their designs.
                       MEMBER KRESS:  So this could be a plant-
           specific size, depending on --
                       MR. OSTERRIEDER:  Yes.  We'd envision each
           plant submitting with a certain size, and we would
           envision a lot of plants may submit with the same
           size.  But it depends on the plant design and the --
                       MR. WARD:  Really, we're looking at fleet
           size, the Westinghouse fleet.  We would -- we are
           doing a scoping study now, just have one size for the
           whole Westinghouse fleet.
                       MEMBER KRESS:  One size fits all
                       MR. WARD:  Yes.  And that is --
                       MEMBER KRESS:  One size for --
                       MEMBER WALLIS:  Can we talk about what you
           mean by "size" now?  If you say -- say, a six-inch
           break, do you mean a six-inch pipe break, or do you
           mean a break of an area in a bigger pipe, or what kind
           of thing are you thinking of?
                       MR. OSTERRIEDER:  We are envisioning a --
           we pick a certain break flow rate, and then we would
           analyze any leaks in any piping sizes to begin --
                       MEMBER WALLIS:  It ought to say that
           you've sort of got a six-inch pipe breaking and
           snapping off or something.  It's the same thing as the
           equivalent area somehow opening up mysteriously in an
           18-inch pipe or whatever, 30-something-inch pipe or --
                       MEMBER KRESS:  It seems --
                       MEMBER WALLIS:  They seem to be completely
           different beasts.
                       MEMBER KRESS:  Well, it seems like the --
           the concept ought to be leak -- how fast you leak.
                       MEMBER SIEBER:  Yes.
                       MR. OSTERRIEDER:  Right.  And I think I
           was trying to say that.  We're looking at how much
           your leakage rate is.  In fact, if you look at double-
           ended guillotine ruptures, the risk significance is
           really low, really low, for the double-ended ruptures
           of any -- the initiating event frequencies are orders
           of magnitude lower.
                       When you look at the leakage rates, at a
           certain leakage rate for all of the different sizes,
           then it does raise the frequency up.  So that's what
           we're looking at -- that, not just the double-ended
           rupture of all of this piping.
                       MEMBER KRESS:  Yes.  It seems to me like
           you ought to get away from that concept, and the rule
           ought to specify a limiting leak rate, or something
           like that.
                       MR. OSTERRIEDER:  Right.  Although we
           think the rule should specify that you're allowed to
           justify and determine what the leak rate is based on
           your design.
                       MEMBER KRESS:  Based on the design.  Yes,
           that's --
                       MR. OSTERRIEDER:  I mean, we really
           wouldn't want to have the leak rate in the rule
                       MEMBER KRESS:  Yes, that's what I had in
                       MEMBER WALLIS:  It matters where the leak
                       MEMBER KRESS:  Well, it certainly would,
           yes.  But that would be part of the rule, too. 
           Somehow that would be captured as --
                       CHAIRMAN SHACK:  It's part of their
           justification for the size that they pick, yes.
                       MR. OSTERRIEDER:  That's correct.  Where
           we think the breaks are, and so forth.  That's
                       MEMBER KRESS:  Your justification would
           have to be in terms of risk some way.
                       MR. OSTERRIEDER:  Well, we're doing a
           justification based on the risk, and then we're
           supporting it with the leak before break deterministic
                       Okay.  Once you would have a specific size
           approved for your plant, the licensee then -- any
           additional plant changes or benefits they would go to,
           and we're going to give a few examples here in a
           minute, would follow the appropriate plant change
           control processes, because we've had a discussion, you
           know, do the plants -- do the licensees need to submit
           future changes?  And we believe that the processes in
           place should dictate that.
                       And if you're falling -- say you want to
           change something in the technical specification,
           certainly you need to submit that or a current
           guideline.  So you may be able to allow the change in
           technical specification, and I'll show -- well, we
           might as well just go to the examples on the following
                       Many of these are technical specification
           numbers.  So approving the rule change and even
           accepting the new break size for that plant does not
           mean the plant can go in and just make these changes. 
           They still have to follow all of the rules.
                       And we've talked about increased diesel
           generator start time.  You know, that's typically in
           the tech specs, and this would allow you --
                       MEMBER KRESS:  Explain to me, once again,
           why they can't already do that.
                       MR. OSTERRIEDER:  Because there's a limit. 
           They have to show that they're meeting the design
           basis requirements, which includes large break LOCA,
           which that's the event driving the quick diesel start
                       MEMBER KRESS:  I mean, could it -- when
           they come in for a change to the licensing basis,
           couldn't they -- couldn't that be part of the change
                       MR. OSTERRIEDER:  It could if they had a
           basis.  But if you have to analyze large break LOCA,
           depending on which methodology you're using, you may
           not be able to justify much longer start times.
                       MR. WARD:  Right.  And I have to get flow
           to the core in 40 seconds, or whatever, to meet a
           large break LOCA, which means diesel has got to start
           at 10, the pump has got to sequence on in the next
           five, come up --
                       MEMBER KRESS:  And what I was saying, you
           come in for -- request to increase that start time,
           and your justification is not that it meets the
           requirements, the justification is I don't need it
           because of these risk considerations.  And 1.174 plus
           the other --
                       MR. OSTERRIEDER:  Well --
                       MEMBER KRESS:  -- it seems like that's a
           perfectly legitimate thing to do under the --
                       MR. OSTERRIEDER:  Well, we felt in
           assessing the different options that the rule change
           was a more holistic approach that would also
           consolidate review times, etcetera.  We could come in
           with a bunch of exemption requests.
                       MEMBER KRESS:  Okay.  Now that, to me, is
           a different reason and probably a valid one.  It gives
           everybody a start on the same page.
                       MR. OSTERRIEDER:  Right.
                       MEMBER KRESS:  So that's --
                       MR. OSTERRIEDER:  Right.
                       MEMBER KRESS:  Okay.
                       MR. OSTERRIEDER:  Again, I'll just --
                       MEMBER APOSTOLAKIS:  Didn't we just say,
           though, that they would still get to come back and
           request changes on individual units?
                       MEMBER KRESS:  Yes.  But at least it gives
           them all sort of a systematic and consistent approach
           to it, I think.
                       MR. WARD:  I would have to come in and get
           an application for my unit to apply the new rule as my
           design basis.  Now, as part of that, if -- if I could
           change my diesel start time, and if it was in the tech
           spec, I would have to have that in as the tech spec
                       If I had already taken that specific
           number out because I had adopted the approved tech
           spec, and the specific number is not in the tech spec
           but it's in the bases, then I would not have to come
           in for that specific approval after I got the design
           basis approval.  That's how we envision it.
                       MEMBER APOSTOLAKIS:  And I guess a lot of
           the generic technical work will be done by the owners
           group rather than individual --
                       MR. WARD:  Yes.
                       MEMBER APOSTOLAKIS:  -- licensees.  That's
           really a great benefit.
                       MR. WARD:  Right.
                       MEMBER APOSTOLAKIS:  I mean, in principle,
           one could use 1.174 to come and request all of these
           changes.  But then each application would have to go
           through a reevaluation of the large break LOCA
           essentially.  That's what you're saying.
                       MR. OSTERRIEDER:  Right.  That's right. 
           And there is justification, and I'm not sure if you'd
           need an exemption request each time or not.  You
           would.  You would, I guess, versus allowing you in the
                       MEMBER SIEBER:  You would need a very
           extensive exemption request because of all these other
           deterministic rules that are out there as part of your
           license conditions or, you know, if you have a --
           well, a 104-type license, you have that, and so that
           would not be a simple thing.
                       MR. OSTERRIEDER:  I really -- I'll just
           point to a couple of examples here.  I guess in the
           interest of time I won't go through them all unless
           you have specific questions.  
                       The third item on here -- we've talked
           about the second item, which is flow balancing.  We've
           talked about -- you know, this list of some of the
           things that we were looking at that plants may do or
           desire to do after this rule changes.  
                       And in the area of accumulators, for
           instance, we're looking at potentially some relaxation
           in the tech specs where now if you're outside of a
           spec on boron concentration or -- or water volume, you
           may have to shut the plant down and do a plant
           transient, whereas it's not a risk-significant event. 
           These are essentially relied on for the large break
                       So we're looking at some, again,
           relaxation of operating parameters to avoid
           potentially plant shutdowns, which -- obvious economic
           benefit, but we believe there's a safety benefit of --
           of the thermal cycling on the plant when -- when it's
           not a risk-significant reason to be shutting down.
                       MEMBER SIEBER:  Is that a real phenomenon? 
           I can't ever remember a plant shutting down because
           accumulators were out of spec.
                       MR. WARD:  The shut down is not such a big
           risk as the startup.
                       MEMBER SIEBER:  Well, you have to fiddle
           -- you have to fiddle on startup to get it right.
                       MR. WARD:  On one of my units we had a
           two-day delay on startup last year with one
           transmitter, trying to get it within a quarter of an
                       MEMBER SIEBER:  Yes, it's pretty tough. 
           On the other hand, I can't remember a plant being shut
           down because of that.  Of course, I don't -- I don't
           know every event that has happened in the last 30 or
           40 years either.
                       MR. OSTERRIEDER:  But even if they don't
           shut down, there may be a lot of work spent at the
           plant if they're on the edge as far as, you know, the
           volume spec.  You know, you certainly need to meet
           their specs, but they may be doing -- spending effort
           in dealing with the idea that they're close.
                       MEMBER SIEBER:  My point is your slide is
           sort of misleading to me.
                       MR. OSTERRIEDER:  Well, the intent of the
           slide really is just to give you some idea of the
           things we're looking at.  These -- you know, we need
           to assess these down the road, and I agree with you. 
           I don't want to mislead you, but I don't want to
           mislead you and not put something like an accumulator
           spec change and then have you come back later and say,
           "Geez, if he was thinking about that, we should have
           put it on the list."
                       So we just -- we're trying to get it on
           here to give you some examples.  And, really, I guess
           I wasn't planning on talking any specifics on this
           anymore unless you have a specific example you'd like
           us to talk about because I think we're going to get
           into some more examples.
                       MEMBER WALLIS:  But if the large break
           LOCA went away, would the fan cooler water hammer
           problem go away?
                       MR. OSTERRIEDER:  We would have to assess
           the fan cooler water hammer problem.  We would have to
           assess what's driving some of these issues and whether
           or not they're prudent --
                       MEMBER WALLIS:  You haven't gotten that
           far yet to reach a conclusion?
                       MR. WARD:  I think there's a high
           likelihood that one may go away or get -- get better
           anyway.  We've added a number of relief valves on
           containment penetrations for that reason.  That could
           have been avoided.
                       MEMBER KRESS:  When the agency was
           redefining the source term for use with the design
           basis accidents, what they did was speculated on what
           possible changes might result if a plant opted for the
           new source survey.  And then they took those changes
           and calculated the risk impact of those, and then made
           the decision whether or not that risk impact was
           significant enough to do or allow a new source survey. 
           This sounds like it's very similar to that.
                       MR. OSTERRIEDER:  It's the same thing. 
           What you don't see here is part of our activities
           throughout this program is to identify and assess,
           from a risk perspective and from a deterministic
           perspective, some of these changes that we have on
           this list.  We fully intend to do that as part of our
           demonstration analysis, but we --
                       MEMBER KRESS:  That's down the road some.
                       MR. OSTERRIEDER:  Well, we need to get
           endorsement that we think that the -- that the
           philosophy of the rule change makes sense.  We believe
           it fully does, and we're hoping to get endorsement so
           that we could go ahead and proceed with that work. 
           But, you know, we have to evaluate the risk, but
           that's what is currently planned in our activities.
                       MR. HEYMER:  I'd also like to point out,
           as Bob said before, that there are specific control
           requirements imposed on licensees for making changes
           today, and that if you move forward with the large
           break LOCA, then want to go and do a change, you have
           to meet those control requirements which may or may
           not require you to go to the NRC staff to seek prior
           review and approval.
                       And under the current process, you've got
           1.174 from the plant-specific basis that would govern
           that, so --
                       MEMBER KRESS:  And we've got 50.59, of
           course, so --
                       MR. HEYMER:  So I think you're covered as
           regards, can you overstep demand?
                       MR. OSTERRIEDER:  Right.  And just to kind
           of try to bring this to closure here, our part, the
           safety margin area, we've talked about most of these
           items.  As part of the risk-informed approach, 1.174
           Reg. Guide, I mean, you're assessing defense in depth. 
           So that's going to maintain defense in depth.  
                       And what we're doing, we've already
           mentioned that, you know, we're going to be looking at
           the CDF, the LERF, the effects on the health and
           safety of the public.  From that perspective, we're
           not eliminating LOCA from these designs; we're looking
           at, you know, retaining LOCA, just defining what the
           maximum size is allowable.
                       And we believe that other design basis
           accidents continue to maintain adequate margin.  You
           know, the idea of, do we need to look for additional
           accidents?  I mean, these accidents should already be
           on the table, and that's what we're going back to look
           at and make sure that we're not increasing the
           importance of some event that we said was bounded
                       And, again, we feel this focuses our
           resources on greater risk-significant activities.
                       MR. WARD:  So just to quickly wrap up our
           part of it, we believe that this approach will
           maintain the typical margins of safety.  We do believe
           this will bring consistency within the regulations. 
           It will help -- if we can follow this approach, it
           will help reduce the amount of resources that the
           staff and us have to spend on Option 3.  And that
           helps our efficiency, our manpower efficiency, and
           effectiveness of the regulatory process.
                       We believe large break LOCA redefinition
           is the preferred industry approach on Option 3.  We
           have looked at the other options that have been
           floated around, and large break LOCA is the only one
           that really makes sense to us to approve.  And we do
           have industry consensus on this one, on this one. 
           This is one we would like to move forward with.
                       But like Bob said, we need some assurance
           that before we do another two years of work and invest
           a tremendous amount of money in it that we're going to
           have a success path to get there.
                       MEMBER WALLIS:  Well, it seems to me you
           read some -- I mean, this sounds reasonable, but then
           I haven't seen the numbers.  And it may be that some
           of the gains may turn out to be small, other ones may
           be bigger than you thought, and so on.  Until we
           really get an evaluation of them, it's hard to make
           the decision.
                       MR. WARD:  They put so many tentacles into
           everything that I don't think any of us can envision
           what all it may impact down the road.  We'd like to
           lay out a framework on how to use it.
                       MR. OSTERRIEDER:  But we are doing the
           quantitative work regarding risk significance.  This,
           in the near term -- we're currently scheduled for a
           July submittal of the risk-significant arguments, at
           least from the Westinghouse Owners Group.
                       MR. HEYMER:  Okay.  With that, we get on
           to a presentation from the Combustion Engineering
           Owners Group.  Dave Bajumpaa from Millstone will go
           over some of the --
                       MEMBER APOSTOLAKIS:  Adrian, just a
           second.  Are we going to go until 12:00 with the
           meeting with industry?
                       CHAIRMAN SHACK:  Yes.
                       MEMBER APOSTOLAKIS:  I thought maybe we
           should take a break, then.
                       CHAIRMAN SHACK:  Yes.  I think there seems
           to be a groundswell for a five-minute break here -- a
           10-minute break.
                                   (Whereupon, the proceedings in the
                       foregoing matter went off the record at
                       10:56 a.m. and went back on the record at
                       11:06 a.m.)
                       MR. BAJUMPAA:  Good morning.  I'm Dave
           Bajumpaa.  I'm a Senior Engineer in the Nuclear Fuel
           and Safety Analysis Group at Northeast Nuclear Energy
           Company, Millstone Nuclear Power Station.
                       I'm here this morning to -- actually, I
           work in the deterministic thermal-hydraulic analysis
           area, which includes the FSAR Chapters 14 and 15
           accident analyses.  I'm here this morning to present
           the CEOG position on large break LOCA definition.  
                       And as we talked about earlier, large
           break LOCA -- by "large break LOCA" redefinition we
           mean to -- we mean the use of leak before break
           technology to really define a maximum mechanistic
           break size that we need to analyze in a design basis
           space, and then continue to analyze the spectrum of
           LOCAs up to and including that maximum break size.
                       As we've talked about already this
           morning, and as you well know, GDC4 currently allows
           for the application of leak before break analyses to
           eliminate dynamic effects associated with the large
           break LOCA.  And as part of risk-informing 10 CFR Part
           50, we would -- we endorse extending this science to
           the remainder of the 10 CFR Part 50 regulations.
                       As we talked, GDC4 doesn't specify a
           specific break size.  It generically -- essentially
           allows a -- it's a generic statement to the effect of
           essentially  having the individual licensees justify
           a maximum break size that needs to be analyzed.
                       We at the CEOG support the consistent
           application of this large break LOCA redefinition
           through both the Appendix K and the containment-
           related analyses.
                       Adrian, Lewis, and Bob talked this morning
           about -- identified I think some of the safety
           benefits and the programmatic approach for the large
           break LOCA redefinition.  The CEOG approach that we
           would take would be very similar to what -- the WOG
           approach as has been discussed previously already.  We
           would continue to use risk-informed technology to show
           the low risk of large break LOCA, use leak before
           break analysis to justify a maximum break size, and
           then continue to analyze the spectrum of LOCAs up to
           this maximum break size.
                       The next slide, please.
                       There's, again, two major areas where we
           see extending the application in this redefinition of
           large break LOCA to 10 CFR 50.46, the ECCS performance
           analysis, and then to the containment-related analyses
           that offshoot from the 10 CFR Part 50 regulations.
                       And this morning I'd like to just present
           -- for the remainder of my presentation, I'd like to
           just discuss -- focus a little more on the containment
           area, as those areas tend at times to be a little more
                       Next slide, please.
                       I think the first two bullets on this
           slide are pretty obvious to -- the most obvious here
           is that we look at containment-related LOCA design
           limits.  We're looking from the perspective of peak
           containment pressure and inside containment EQ
           temperature profiles.
                       The next few bullets there are dealing
           with the -- a more subtle analysis that we have to do. 
           We analyze -- as for peak containment pressure, we'll
           analyze to maximize containment pressure and
           temperature.  But we also have to perform an analysis,
           a separate LOCA analysis, that looks to maximize the
           close cooling water system temperatures.  
                       It's a similar kind of containment LOCA
           analysis, except that we'll -- instead of using a
           fouled set of CAR coolers to maximize the containment
           temperature and pressure consequences, we'll actually
           use clean CAR coolers to put as much energy into our
           closed cooling water systems as possible.  And you
           continue to use a fouled heat exchanger on our closed
           cooling water to service water; that's our ultimate
           heat sink.
                       So we do two distinctly different large
           break LOCA containment-related analyses.  The analyses
           that we do to maximize the RBCCW -- I'm sorry, I use
           RBCCW because that's reactor-building, closed cooling
           water system.  That's what I call it in my plant, so
           I apologize if I stumble through that.
                       Some of the key parameters we analyzed,
           design limits we analyzed for peak RBCCW temperature-
           related effects are the -- our containment -- our
           safeguards rooms, our ECCS and containment spray pump
           temperature profiles.  They're for the room
           temperature profiles that are in a building, and
           that's going to affect the EQ of our HPSI/LPSI
           containment spray pumps -- safety injection and
           containment spray pumps.
                       Other design limits that we have to
           analyze  with this peak -- related to this peak RBCCW
           analysis are closed cooling water inlet and outlet
           temperatures at the different components in the closed
           cooling water system at the containment air recirc
           coolers, the shutdown cooling heat exchangers, and the
           spent fuel pool cooling heat exchangers.
                       Again, it was brought up a little earlier,
           the generic -- other issues related to containment
           design limits, issues related to the Generic Letter
           96-06, potential water hammer loads associated with
           the LOCA with the concurrent LMP, and the potential
           for voiding in the car coolers.  And then, once you
           resequence your closed cooling water pumps on, you
           will get some significant hydrodynamic loads in the
           CAR coolers.
                       Some of the other components -- the
           subcompartment pressurization analysis.  That's a
           traditional design basis analysis where we looked at
           the double-ended guillotine, and we looked to apply
           this large break LOCA redefinition effort in order to
           -- to limit the maximum break size we analyze.
                       Another issue -- the last bullet on that
           slide is I've got a relatively significant issue
           that's still out in the Generic -- I guess it's
           Generic Safety Issue 191 dealing with debris
           generation in the transport over to the -- with
           regards to the containment sump screens and our
           containment sump design verification.
                       We believe that the application of large
           break LOCA redefinition is appropriate in this arena
           as well as the rest of the containment design areas
           and 50.46.
                       Looking at the next slide, the -- if we're
           looking at the containment-related design limits, we
           typically have very little analytical margins of these
           design limits.  What I will calculate for a peak RBCCW
           temperature, say at the outlet of my CAR cooler, is
           the actual limit that our CAR cooler piping can
                       I don't have any margin in many of the --
           related to many of these design limits.  Changing
           these design limits is costly.  For example, the CAR
           cooler outlet temperature, if I have to increase that
           containment temperature, I have many, many, many
           calculations of structural supports and many stress-
           related calculations that have to be redundant.  
                       It's very expensive to us, so it's --
           analytic margin is a very good thing to have.  So if
           we have increase analytic margin, we can accommodate
           some unforseen plant problems that we run into on a
           day-to-day basis at our plants.
                       And looking at -- you know, trying to
           quantify some of the margin, you know, if we look at
           the containment pressure design limit, the containment
           pressure, we'd expect a reduction if we're allowed to
           limit our -- apply -- redefine our large break LOCA. 
           We'd expect about a 10 percent increase or a 10
           percent reduction in containment pressure, which would
           increase our analytic margin by that 10 percent.  
                       We wouldn't look to change any of the
           design -- containment design, you know, thicknesses or
           any kind of structural integrity of the containment. 
           But we'd use it for -- use it to get that and
           establish the analytic margin.
                       Next slide.
                       I'd like to look at a little more detail
           on containment design pressure here, just to show you
           what typically is out there.  This is actually related
           to my plant at Millstone.  These specific numbers are
           related to my plant at Millstone but are very similar
           to the rest of the CEOG fleet.  
                       The containment design pressure I have is
           a 54-pound containment design.  My peak calculated
           containment pressure falling in my LOCA is 52.9 psi. 
           Peak calculated pressure falling in the main steam
           line break is 53.8.  So I'm actually steam line break
           limited at Millstone, at this point -- Millstone II at
           this point.
                       So redefinition of large break LOCA is not
           going to directly gain the --
                       MEMBER KRESS:  Do you consider those two
           numbers significantly different?
                       MR. BAJUMPAA:  No, I do not.
                       MEMBER KRESS:  Okay.  So both of them
           limit the --
                       MR. BAJUMPAA:  Right.  Right.  But we
           would certainly advocate the redefinition of large
           break LOCA to get more margin for the LOCA.  If we can
           get that extra 10 percent or so margin, it would
           certainly simplify our design change process to -- to
           perhaps allow us to do -- right now, if I had proposed
           a design change, because I'm so close to the limits,
           I have to look at both accidents.  If I had more
           analytic -- and I have to look at both accidents
                       If I was able to get a little more margin,
           analytic margin for my LOCA, perhaps I could look at
           that one qualitatively.  But I would still have to
           look quantitatively at the steam line break.
                       So there's not a different benefit on
           containment pressure here, but it is certainly -- it
           does simplify my life in the -- maintaining my plant's
           configuration and our design change process.
                       Some of the other -- next slide, please.
                       Some of the other areas -- the inside
           containment EQ profile.  Again, increased analytic
           margin between the post-accident calculated
           temperature profile and the EQ temperature envelope of
           equipment inside containment, that's -- again, we're
           going to get some increased analytic margin here if we
           are allowed to redefine the large break LOCA.
                       Similarly, the ECCS room temperature
           profiles, if I have a -- if I am able to limit my
           break size, for example, to something as large as
           branch line break, up to something like that, that
           would get me some additional temperature margin, so
           that I could -- so it's just an increase in margin
           there as well.
                       And the same thing between the CCW
           temperature when it might have increased analytic
           margin between what I calculate post-LOCA with clean
           CAR coolers versus my coolant CCW temperature when
           it's in my design limits right now.
                       MEMBER SIEBER:  With respect to the EQ
           limits on electrical equipment, how does that benefit
           you since you already have the equipment qualified to
           the original profile?  Is it in replacement parts or
           aging life, or how does that come up in -- in some
           cases, you may be able to recall.
                       MR. BAJUMPAA:  Yes, there is some
           equipment that actually has -- I have in my plant
           right now that -- it's definitely an aging issue.
                       MEMBER SIEBER:  Okay.
                       MR. BAJUMPAA:  It also comes from the
           perspective of showing the long-term LOCA profile
           compared to the test profile and actually analytically
           proving that the test profile that the equipment is
           tested to bounds the actual predicted LOCA profiles.
                       I actually have some equipment that is
           very marginal that we have to do a pretty
           sophisticated analysis internally to demonstrate that
           with the double-ended guillotine LOCA that our
           equipment would survive that for the 30-day time of
           the accident and including them in a four-year life. 
           So there would be some equipment potentially that we
           could avoid having to replace.
                       MEMBER SIEBER:  I think I'll ask no more
           questions about that.  
                       MR. BAJUMPAA:  Okay.
                       MEMBER SIEBER:  Thank you.
                       MR. BAJUMPAA:  Sure.  So I've sort of
           established to this point, hopefully, that what we're
           trying to do here is increase the analytic margins to
           our design limits.  Now, what would we do with that
           analytic margin?  And this next slide sort of leads
           into some of the areas in the containment-related
           design benefits that we would get here.
                       One area, we would look to relax perhaps
           the CCW flow limits through our CAR coolers.  Right
           now at my plant I have a very, very small window in
           which I can set my CAR cooler flow outlet valves to
           get the proper flows.  I have to make sure that I have
           enough minimum flow through the CAR coolers, so that
           I am assured to pull off enough heat removal so that
           I don't exceed my containment design pressure when I'm
           looking to maximize my containment design pressure.
                       But I also to make sure that I don't have
           too much CCW flow going through my CAR coolers.  If I
           start having too much flow, I might -- with a clean
           CAR cooler, then I might actually increase my peak
           calculated RBCCW temperature following the LOCA.  And
           so I actually have a very tight constraint right now
           that I have at my plant to maintain a minimum flow
           that ensures the containment pressure is met and a
           maximum flow that ensures that I don't exceed the peak
           CCW temperature limits.
                       MEMBER SIEBER:  Do you have service water
           temperature limits?
                       MR. BAJUMPAA:  Yes.  We do have service
           water temperature limits.  Primarily, with the
           containment-related analysis, that comes in from the
           ultimate heat sink, the --
                       MEMBER SIEBER:  Okay.
                       MR. BAJUMPAA:  -- sound temperatures, yes.
                       MEMBER SIEBER:  And do you also have RWST
           temperature limits?
                       MR. BAJUMPAA:  That is correct.
                       MEMBER SIEBER:  Which often is hard to
           meet in the summertime?
                       MR. BAJUMPAA:  That is -- yes, that is
                       MEMBER SIEBER:  Okay.  And those would be
           relaxed if you had a smaller break size?
                       MR. BAJUMPAA:  That would -- it would
           certainly -- it would help.
                       MEMBER SIEBER:  Okay.
                       MR. BAJUMPAA:  I'm not sure on the RB we
           have to look, you know, in an integrated fashion
           through all of the -- but, yes, that would certainly
           help the containment.
                       MEMBER SIEBER:  I know that Farley had
           those problems, correct?
                       MR. BAJUMPAA:  Right.
                       MEMBER SIEBER:  Okay.
                       MR. BAJUMPAA:  Right.  So I should have a
           bigger window as far as CCW temperature to flow -- to
           set a bigger window in my plant right now.  I think
           I've only got a 25 gpm target window to set through a
           CAR cooler, so that I don't have a minimum flow.  When
           I take the minimum flow, I also have to drop off to
           account for pump degradation and instrument
                       So I have a very tight window.  It's only
           like 25, 30 gpm that I can set my CAR cooler outlet
           valves within, which is a bit of a challenge and we do
           have to fiddle with the valves from time to time to
           make those -- to maintain our configuration
                       MEMBER WALLIS:  Fiddling with the valves,
           is that done remotely?
                       MR. BAJUMPAA:  No.  These are actually
                       MEMBER WALLIS:  Someone has to go in there
           and turn them?
                       MR. BAJUMPAA:  Yes.  Somebody would go in
           there and turn them, not during an accident, but
           during the refueling outages and stuff when -- or
           whenever we do anything that might change the
           configuration of our CCW system we'd have to go back
           and do a flow balance.
                       MEMBER SIEBER:  Well, you end up having a
           range of adjustments because as you operate the plant
           the CAR coolers become fouled and flow goes down.
                       MR. BAJUMPAA:  Yes.  We typically --
                       MEMBER SIEBER:  To some extent.
                       MR. BAJUMPAA:  To some extent, that is
           true I guess perhaps for some plants.  But on our
           plant we currently do cool our CAR coolers with a
           closed cooling water system and maintain pretty decent
           chemistry there.
                       MEMBER SIEBER:  So you're better off.
                       MR. BAJUMPAA:  We typically don't have
           issues with car cooling, fouling.
                       MEMBER SIEBER:  Okay.
                       MR. BAJUMPAA:  Yes.  Other potential
           applications that we use for this increased analytic
           margin we'd get with our potential large break LOCA
           redefinition here, I might be able to increase my tube
           plugging limits that I have to maintain in my
           configuration right now on my CCW to service water
           heat exchangers, my shutdown cooling heat exchangers,
           and the CAR coolers.
                       The service water areas, being a raw water
           system, that's probably the area where I'd be most
           sensitive about tube plugging.  Other areas -- as
           alluded to a little earlier, I have actually made
           submittals on our docket, and we just received a
           license amendment regarding the increase in our
           ultimate heat sink temperature limits.  Actually, it's
           more of an issue there that I just went through on my
                       Another potential area of use for this
           increased margin would be to accommodate any future
           potential power upgrades.  Because I'm so close right
           now with the LOCA on containment pressure, increasing
           the power, that event turns out to -- that may
           actually put the LOCA containment calculated pressures
           higher than the design pressure containment.
                       If I were to do a power upgrade in the
           future with a double-ended guillotine steam line break
           there, even though it's up there right up and close,
           that's actually limited by my zero power case by the
           additional water inventory and the steam generators.
                       I guess the next slide -- this next slide
           really is a summary of actually when Millstone was
           going through its 54(F) configuration management
           related outages, this is a listing of the areas where
           we had analytic problems that we had to straighten out
           our configuration.  And that resulted in us having to
           reanalyze our containment pressurization analysis
           associated with the large break LOCA.
                       We had increased safety injection.  We had
           to increase our safety injection pump flows.  We had
           to increase the spent fuel pool cooling heat loads
           that were assumed in the analysis.  We had increased
           containment spray header fill times when we looked at
           in more detail.
                       Small -- very, very small issue here
           obviously, the containment paint thickness, but that
           does play into -- I have to -- I have a maximum paint
           thickness that I have to assume on my passive heat
           structures inside containment.  And during the 54(F)
           outage we identified that the paint micrometer was
           thicker than what we had assumed in the analysis.
                       So that was another contributor to making
           us reanalyze that event and in the increased refueling
           water storage tank temperature.  That's -- those are
           things that we had to deal with during our 54(F)
           outage, and now we have a solid configuration in our
           running well.
                       Another area where we just wanted to make
           one point with this slide, that we really feel -- the
           CEOG feels that we should consistently redefine the
           large break LOCA across the entire spectrum of the 10
           CFR Part 50 requirements.  We think that is the way to
           go.  It's currently acceptable to use LOCA
           redefinition for GDC4, and to extend that application
           through both the 50.46 and the containment-related
           areas, we think that will allow us to take advantage
           of some of the potential safety benefits.
                       I throw up as an example on this slide the
           emergency diesel generator start times to -- to try to
           enhance the diesel reliability.  But that diesel
           generator start time is driven by a lot of things. 
           It's driven by the 10 CFR 50.46 ECCS performance
           analysis, where we are looking at getting our high
           head and low head safety injection pumps up to speed
           in the adequate time to combat the double-ended
           guillotine LOCA.
                       But I also have to have my CAR fans start
           my closed cooling water pumps for the containment-
           related areas.  They need to sequence on the diesel
           generator and start to accommodate these double-ended
           guillotine LOCAs.
                       If I am going to increase this diesel
           start time, it's a major effort on behalf of my plant
           from a design change perspective.  I have to look to
           make sure that my steam line break containment
           performance does not now become more limiting than the
           LOCA with regards to maximizing the water hammer loads
           on the CAR coolers, the RB temperatures, and things
           like that.
                       So it's -- to -- to -- right now, on
           Millstone, my diesel start is tied in right now to --
           in order to prevent too many -- too large hydrodynamic
           loads on my CAR coolers, I need to start my diesel in
           the same -- I can't relax that directly right now
           unless I get -- unless I'm able to redefine the LOCA. 
           Then I will not be able to increase my start time, if
           I just apply it to the -- if I apply LOCA redefinition
           to the 50.46 area only.
                       So it's got to be an integrated overlook,
           and I've got to look at not only the containment-
           related LOCA analysis, I've got to look at the ECCS
           analysis, and I've got to look at all the rest of the
           Chapter 14/Chapter 15 accident analyses to make sure
           I'm not affecting aux feedwater start times for my
           loss of normal feed analysis in Chapter 14.  So it's
           got to be a big integrated look to get this increased
           diesel start time and yet still maintain the proper
           configuration at my plant.
                       And I guess the last slide is just a
           summary that the CEOG -- as I have indicated and
           alluded to in earlier slides, the CEOG does support
           the consistent application of the large break LOCA
           redefinition throughout the entire 10 CFR Part 50
                       CHAIRMAN SHACK:  Let me catch up one thing
           back to Mr. Ward.  Something slipped through that I'd
           sort of like to understand.  Although we're doing this
           under Option 3, is your selection of the maximum pipe
           size going to be basically a deterministic argument
           based on the 1061 kind of arguments, that you're going
           to have some margin to leak and then some margin on
           crack size?  Or are you going to go through and look
           at the risk significance of various leak sizes?
                       MR. OSTERRIEDER:  It's a combination. 
           We're considering the risk significance and the
           deterministic piece.
                       CHAIRMAN SHACK:  Okay.
                       MR. WARD:  Yes.  And, historically, we had
           started this before Option 3 became a program.  We
           wanted to get into redefining the LOCA.  So I guess we
           have been doing this in conjunction or in support of
           the staff's effort to come up with some options under
           Option 3.
                       MR. HEYMER:  Terry Rieck from Excelon will
           talk to you about the BWR perspective.  He's
           representing the BWR Owners Group.
                       MR. RIECK:  Good morning.  For those of
           you who don't know who Excelon is, we're now in the
           merged organization of Con Ed and PECO, so -- I know
           a lot of you don't know how much we're changing out
           there in the industry.
                       But I'm here representing the BWR Owners
           Group.  Excelon does own 10 BWR units, and so we are
           a big part of that owners group.
                       We formed a committee recently, a
           technical committee, to look into Option 3 risk-
           informing Part 50, the technical requirements. 
           Frankly, we were behind on where the PWRs were, PWRs
           having started a year and a half ago or so to look
           into this.  We are behind because we saw we had some
           margin in large break LOCA, and we saw where the PWRs
           were going and -- and didn't jump in right away.
                       But within the last few months, we felt we
           needed to get more involved to see where the benefits
           might be for us.  And we formed this technical
           committee.  We've now met a couple of times, and we
           started talking about the same things that the PWRs
           were doing.
                       Very quickly, we got into determining that
           redefining the large break LOCA should be our highest
           priority.  As I said, we kind of dismissed that a year
           ago or so, but once we started talking about it we saw
           that it met the criteria, the framework, that the
           Commission was talking about in terms of Option 3. 
           That is, there was some significant safety
           enhancements that could be made on our plants, but
           also have a burden reduction for us, and there was
           some cost that we had to incur to get there.
                       So when you looked at it, when we looked
           at it in terms of the PWR approach, we saw the same
           safety enhancements that the PWR saw.  We talked about
           diesel generators starting in 30 seconds instead of 15
           seconds, and what would that mean to the reliability
           of the diesels to the reliability of the electrical
                       And we saw that our CDF for our large
           break LOCA was way down in the weeds, very low, and
           our small break LOCA was higher and other -- other
           actions that relied on loss of -- relied on offsite
           power were higher, and, thus, the diesels are very
                       So we ended up with the same safety
           benefits and felt we didn't meet the safety of the
           plant significantly.  And, you know, as we talked more
           and more about it, the members of our committee from
           the various utilities said, "Well, of course, you
           know, the setting up of valves in certain ways and the
           ECCS pumps would all enhance the small break LOCA." 
           And the large break LOCA was so low in CDF, you know,
           it might, as mentioned here, increase its CDF.  But it
           was so low it was an insignificant increase.
                       We very quickly said, "Yes, we can gain
           the safety benefit, and the burden reduction could
           also be significant."  The same thing is talked about
           on the PWR side.
                       As I mentioned, we do have more margin in
           the large break LOCA, so it kept us from getting in as
           quickly.  And we realized also that we haven't delved
           in as much into fracture mechanics probability and
           leak before break like the PWRs, so our cost might be
           more to get into this than the PWRs.
                       But what that meant is we would incur a
           larger cost for the burden reduction, but it might
           also mean an alternate break size, as we may not be
           able to justify as small of a break size as the PWRs. 
           And as each of the owners groups talked about here
           today, that's part of our industry proposal is that
           each vendor would have to propose their own break size
           based on what they could justify.  So we realize we
           may not be able to get the same break size.
                       So, again, just to summarize, we felt the
           -- that large break LOCA redefinition was our most
           beneficial path to go down.  But we did make this a
           committee that looked at other options, because the
           other owners groups had already done that.  But we
           hadn't had the chance to look and see what might be
           our highest priority, and, thus, we did look at other
           options and came up with half a dozen other options
           that we ought to pursue.  So we are looking other
                       So we see large break LOCA as a high
           priority.  We see a benefit for that as well as
           working with the Commission and the owners groups in
           terms of -- of the framework and how it might be
           further development through this process in the large
           break LOCA.
                       So our follow-on activities on the second
           slide here are to continue in the large break LOCA
           arena, better define the safety benefits as well as
           our burden reduction, essentially do the cost-benefit
           analysis, but also assess the various approaches on
           fracture mechanics and leak before break.  
                       So we've got a lot of work ahead of us to
           catch up to where the PWR is.  But, again, I want to
           emphasize that is our top priority in the working
           group, but we are also looking at other options.  And
           we're playing in -- or we're working in this arena to
           get more experience in that and know where our cost
           benefit might be for other options down the road.
                       CHAIRMAN SHACK:  Would you be looking at
           changes in GDC4 on the requirements that you can't
           apply leak before break, for example, to piping within
           a granular stress corrosion cracking?
                       MR. RIECK:  We have -- the BWRs have had
           IGSCC problems, and we have also done some mitigation
           to those problems over the years.  And so, in our
           discussions, we felt that we'd have to do a lot of
           justification to show that we have improved on the BWR
           pipes.  And the smaller pipe size may not be
           justified, but the larger pipe size, where we may not
           have seen that, we might be able to justify that.  So
           that's the path that we have taken.
                       That's all I have to present.  I'd be
           repeating a lot of what the PWR said, but I made the
           points.  We are moving down this path.
                       MR. HEYMER:  The B&W Owners Group couldn't
           be here today, but they have a similar program
           underway.  They are supporting this activity.  They
           support this approach, and they believe, looking at
           50.46, that redefining the large break LOCA is the
           priority that we should be looking at in this
                       And so I guess, in summary, what we've
           tried to do today is explain to you -- give you some
           background of how we reached our conclusions on 50.46
           and redefining the large break LOCA.  All owners
           groups have evaluated this and have continued to look
           at it as we've interacted with the staff over the last
           15 months or so and explained our positions and
           thoughts to the staff on where we think the emphasis
           needs to be placed in improving 50.46.
                       You heard today some discussion on the
           benefits as regards to margin, the operational margin,
           scheduling of work activities, the priority of work
           activities, and consistency in the regulation.  And we
           believe that by going down this path of redefining the
           large break LOCA we can more effectively focus our
           resources on those issues that are safety significant
           which will ultimately enhance the overall safety
           profile of the plants.
                       So that's what we came with today.  We're
           looking to go to the next step, and you heard
           Westinghouse talk about evaluations that are underway. 
           As I said, owners groups have provided funding because
           we saw recognition that if we're not going to go down
           the large break LOCA path that we need to hear about
           that, because we do really believe that it is the
           priority and the one that we should be looking at to
           get the maximum benefit, both from a resource and a
           safety perspective.
                       And before these folks go off and spend a
           lot more money, I think we've got to come to a
           resolution of the direction in which we're going.
                       MEMBER WALLIS:  So what are you hoping for
           from the ACRS at this point?
                       MR. HEYMER:  Well, we understand that this
           was really a familiarization discussion with you to
           explain our position, and we look forward to hearing
           what the staff is going to say on the matter.  And we
           understand that there are some papers going up to the
           Commission, because as you rightly said this is --
           this is a significant step and they want Commission
                       And we hope that it's -- it's the decision
           that supports what we've explained to you this
           morning, because we think that is the right thing to
                       MEMBER WALLIS:  We have to listen to the
           staff and then -- I don't know what the staff will
           say.  If the staff agrees with you, then it would seem
           we don't have much to do.  If the staff disagrees with
           you, maybe we need to get involved and --
                       MR. HEYMER:  Well, I mean --
                       MEMBER WALLIS:  -- try to sort things out.
                       MEMBER KRESS:  I think it's a question of
           whether we agree or not, not whether the staff does.
                       MEMBER WALLIS:  Yes, but we haven't seen
           that much.  And we've seen sort of the perspective of
           you're about to go down this path, and there may be
           some nice country to discover if you take the path. 
           But we haven't really seen much in the way of numbers
           or technical analysis or -- I mean, there's hopes that
           if you did this you might be able to get something
           here.  I think we need something a little more
           substantial in order to give a solid yes or no or
                       MR. HEYMER:  And I think that what we're
           looking for from an industry side is the fact that,
           yes, okay, it's worth progressing, and, yes, we can
           continue to go down this path, and we will do the
           analysis.  And we can come back once we've done those
           detailed analyses and provide you a further -- a much
           more detailed description of what we're finding and
           where we're going.
                       But we feel we should be confident that we
           can do that, and we can achieve --
                       MEMBER WALLIS:  Before you plan the
           expedition to climb this mountain, you want to know if
           there's going to be some taboo or something that says
           you can't go there anyway.
                       MR. HEYMER:  Well, yes.  And if someone
           says that whether you -- you can do what you want but
           you're wasting your time, and, you know --
                       MEMBER WALLIS:  Right.
                       MR. HEYMER:  -- then we're going to have
           to take a look at doing risk-informed, and are we
           actually risk-informing the regulation, because we
           think this is a central element and it -- it does send
           a very clear signal that this is what we want to move
           towards, improving the process.
                       MR. OSTERRIEDER:  Right.  In all the
           discussions we've had to date, we haven't heard of any
           issues brought up that we didn't feel were -- that
           were insurmountable.  We thought that all of the
           issues that were identified to us thus far are issues
           we can deal with.  And this continues to make sense
           and the most sense, but, you know, we just need to
           understand if there are issues there and get them on
           the table and move forward.
                       CHAIRMAN SHACK:  Well, I think perhaps
           this -- we really do need to hear from the staff. 
           That's the next step.  And we'll be doing that at
           12:30.  We'd like to take a break for lunch now.  Come
           back at 12:30.
                                   (Whereupon, at 11:42 a.m., the
                       proceedings in the foregoing matter went
                       off the record for a lunch break.)
           .                     A-F-T-E-R-N-O-O-N  S-E-S-S-I-O-N
                                                   (12:32 p.m.)
                       CHAIRMAN SHACK:  We're ready to restart
           the meeting, and we'll have the staff presentation. 
           I guess we're going to have an overview from Tom King,
           Mary Drouin, and Mike Mayfield, among others -- the
           usual suspects.
                       MR. KING:  My name is Tom King.  I'm with
           NRC's Office of Research.  With me at the table is
           Mike Mayfield, Division Director, Division of
           Engineering Technology and Research; Mary Drouin from
           the PRA Branch; and Alan Kuritzky from the PRA Branch.
                       If I could have the second slide.
                       What we want to talk about today is give
           you a status report on where we stand on looking at
           50.46.  We haven't sent you anything in advance. 
           We're not asking for a letter.  This is work in
           progress, but I think we've reached a point where it's
           worthwhile having some interactions, and at least
           informally getting your reactions, your feedback.  And
           we'll get to a schedule slide later on, and we will be
           back several times before this is all done.  
                       This is sort of an initial overview of
           what we've done, sort of some general conclusions
           we've reached, and some additional work things,
           follow-up things we're still working on.  And like I
           said, we'll be back later to talk about further
           progress in this area.
                       I'm going to give a little introduction
           and overview of where we stand.  Mike is going to talk
           about in more detail redefining the large break LOCA. 
           And then Alan Kuritzky is going to talk about where we
           stand in terms of some near-term conclusions or
           recommendations that we're thinking of proceeding with
           and the longer term aspects of 50.46.  If I could have
           the third slide, please.
                       As you recall, this is work being done
           under what we call Option 3, and Option 3 was
           basically an effort to go in and look at the
           regulations, technical aspects of the regulations, try
           and identify what the -- from a technical standpoint
           what things were candidates to be changed based upon
           risk insights.  And those changes could go either way. 
           They could fill gaps in the current regulations that
           risk insights say need to be filled, or they could
           remove some unnecessary burden that risk insights say
           are not very risk significant.
                       Our plan in Option 3 is to do what we call
           a feasibility study.  That is, go to the Commission,
           do enough work to go to the Commission and say, "Hey,
           here are some things that are feasible to change." 
           Not give them a rulemaking, but get them to buy in up
           front that, yes, we've done enough work to establish
           certain changes are feasible, and then the rulemaking
           would actually get into the details and the exact
           wording of the changes, and go through the normal
           process which is usually about a two-year process.
                       The rulemaking process involves a lot of
           public interaction, but we've also tried to have with
           -- to work under Option 3 public interaction as well. 
           And you heard this morning we've had a number of
           meetings with the owners groups, and they've all been
           public meetings.  We had a workshop to try and get as
           broad input as we could on this activity, and we'll
           continue to do that as we proceed.
                       MEMBER WALLIS:  Are you getting what I
           would call real public input?
                       MR. KING:  We have not gotten much from
           outside the industry, no.  We've invited people, and
           some of them attended, but we haven't gotten much in
           terms of feedback.
                       MEMBER WALLIS:  I think this is an issue
           where, you know, I would really be interested in what
           the sensible, informed public would think of about
           this sort of change, and not people who have something
           to gain by it one way or another but those who -- you
           know, whose interests you are trying to protect.
                       MR. KING:  I'd like that feedback as well. 
           I'm not sure exactly how to get it other than you keep
           asking for it and hope it comes in.
                       MS. DROUIN:  We have had at the public
           meetings real public.  They have come to some of the
                       MR. KING:  Yes, but they haven't said
                       MS. DROUIN:  They haven't said much.
                       MEMBER APOSTOLAKIS:  I don't understand
           why they are part of -- they use different names,
           means --
                       MR. KING:  Non-industry.
                       MEMBER APOSTOLAKIS:  Okay.  Non-industry. 
           Much more factual.  In fact, to protect the sort of
           public that's sitting in front of us.  Let's not
           forget that.  The public has safety.
                       MR. KING:  We're following in all of these
           Option 3 activities what we call this framework
           document, which we've discussed with the committee
           before.  It sort of lays out the ground rules as how
           we go through and look at regulations and what the
           guidelines are for making judgments on whether we'd
           make a change or not make a change, and it involves
           defense in depth, safety margins considerations, as
           well as some risk guidelines.
                       And the question came up this morning,
           well, why not use Reg. Guide 1.174?  In theory, any
           licensee today could come in with 1.174 and propose a
           change to the large break LOCA for their plant, go
           through all the analysis it would require as to staff
           review and approval.
                       Option 3 is really trying to make some
           generic changes, not require plant-specific stuff in
           every case.  And that's why the framework in Option 3
           is a little different than what's in 1.174.  1.174 is
           delta CDFs, delta LERFs.  You're making changes from
           the current plant risk profile.
                       MEMBER APOSTOLAKIS:  Let me understand
           that a little better, Tom, because it's something I
           have on my mind.  When you change a rule, you can
           still use the idea of delta CDF and delta LERF to
           evaluate the change you're about to make.  In other
           words, you are using the idea behind the 1.174, even
           though you are not changing the licensing basis of a
           specific unit.
                       MR. KING:  When you change a rule,
           particularly when it's mandatory on everybody, and you
           go through the backfit analysis, you have to show that
           the incremental improvement in safety is substantial. 
           And there are guidelines in the reg. analysis
           guidelines, delta CDF, for example, that's used to do
                       MEMBER APOSTOLAKIS:  But in addition to
           those, though, shouldn't delta CDF be small?  Or do
           you think that's covered already by the regulatory
                       MR. KING:  If we're imposing a new
           requirement, we want to make sure that the improvement
           in safety is not minuscule, that it has some
           substantial improvement in safety.  So there's a delta
           CDF guideline in the reg. analysis guidelines.
                       MEMBER APOSTOLAKIS:  I guess now I'm a bit
           more -- when you are imposing a requirement, that
           means that the delta CDF is negative, is it not?  And
           that's why the regulatory analysis applies.
                       MR. KING:  But the change is an
           improvement in CDF, and CDF goes down.  
                       MEMBER APOSTOLAKIS:  Okay.
                       MR. KING:  Yes.
                       MEMBER APOSTOLAKIS:  If, on the other
           hand, you change a rule in a way that, really, there
           is only relief, then I would expect a positive delta
           CDF.  So there shouldn't be a question of regulatory
           analysis.  But there should be a question of whether
           the delta CDF, which is not positive, is acceptable.
                       MR. KING:  Yes.
                       MEMBER APOSTOLAKIS:  Which brings into
           this 1.174 what I feel the idea is behind 1.174.
                       MR. KING:  Right.  Right.
                       MEMBER APOSTOLAKIS:  So that would be one
           where you're doing it.  But then, this morning --
           again, I'm trying to understand how this works -- we
           said that, yes, even if you change the rule, then each
           licensee will have to come to you with a request to
           actually be allowed to change it for their facility. 
           And that's not clear to me.
                       MR. KING:  Well --
                       MEMBER APOSTOLAKIS:  Why do they have to
           do that?
                       MR. KING:  It depends on the rule change
           that's made.  I guess in an ideal situation, you'd
           make a generic rule change, specify a new break size,
           and maybe people now would have to submit on their
           reload analysis to conform to that new break size. 
           But they wouldn't have to come in and justify that
           break size.
                       I think what we've kicked around is there
           is -- you know, it's not clear we can define a generic
           break size for everybody -- a new one.
                       MEMBER APOSTOLAKIS:  Okay.
                       MR. KING:  Perhaps its class of plant-
           specific or vendor-specific -- or perhaps it's plant-
           specific, in which case you -- I think you heard this
           morning that if it's plant-specific, maybe each
           licensee -- what the rule change would do, it would
           open the door for each licensee to come in and propose
           for his plant the new break size that makes sense
           based upon his risk assessment, his plant design. 
           That's one option.
                       And what this rule change would do,
           basically, then, would eliminate having to have an
           exemption to the current regulation to do that. 
                       MEMBER APOSTOLAKIS:  So they wouldn't need
           to concern themselves with Regulatory Guide 1.174 at
           all, because that's in the rule.
                       MR. KING:  What we would have to do in
           that case is put out a new Reg. Guide that says, okay,
           if you're going to come in under this new rule that
           opens the door, here's the analysis we'd want to see
           and here's the acceptance criteria.
                       MEMBER APOSTOLAKIS:  So you might repeat
           some of the requirements of 1.174 --
                       MR. KING:  Yes.
                       MEMBER APOSTOLAKIS:  -- if it is
                       MR. KING:  If people -- right, exactly.
                       MEMBER APOSTOLAKIS:  In other words, you
           may request a risk assessment, an evaluation of delta
                       MR. KING:  But today, if somebody wants to
           come in under 1.174, in this particular case, they're
           going to have to ask for an exemption to 50.46.  And,
           you know, the Commission has told us in pretty clear
           terms that if -- if you're starting to make a lot of
           exemptions in a certain area, you ought to start
           thinking about a rule change.  And that's one reason
           for not just saying, "Go use 1.174" on something
                       MEMBER KRESS:  That's the best reason --
           explanation that I've heard so far.  That's helpful.
                       MR. KING:  Okay.  Next, side 4.
                       Where we stand -- within the past four or
           five months, we've pretty much been in an information-
           gathering mode, gathering information from the
           industry, from the owners groups you heard this
           morning, in terms of what their thoughts are, what
           work they've done looking at this issue, and we've
           been doing our own work in-house looking at various
           options and the technical basis for those options,
           using our framework and looking at the risk
           information associated with those options and how it
           stacks up against the framework.
                       And we're now at the point where we've
           gathered enough information where I think we're
           settling in on some at least preliminary conclusions
           and preliminary approaches, and that's what we're
           going to talk about today.
                       We're going to talk about what we consider
           is feasible to go forward with in the short term.  By
           the "short term" I mean with a paper to the Commission
           in June, and then some things that we think are
           potential longer term improvements, but we need some
           more time to work on those.  So you'll hear about both
           of those.
                       If I can have the next slide we'll talk
           schedule a minute.
                       This is sort of the first time we've come
           forward in a public setting and talked about what
           these preliminary conclusions are and what we want to
           pursue.  So we think, clearly, we want to have at
           least another public meeting before June to talk about
           these in more detail and get some feedback from others
           besides this committee.  So that is factored into our
                       I think we want to come back to the
           committee after that and, you know, tell you where we
           stand, having factored in input from that public
           meeting and additional work we're doing.  We would
           intend to get you a draft Commission paper to look at
           in mid-May, and then we would want to come back to the
           committee at your June full committee and ask for a
           letter on this before we actually send the paper to
           the Commission the end of June.
                       MEMBER APOSTOLAKIS:  So the subcommittee
           meeting will follow the SECY paper.  We'll have an
           opportunity to read the SECY paper before the meeting,
           right?  Or is that after?
                       MR. KING:  We are proposing another
           subcommittee before you actually get the paper, and
           then give you the draft paper before the June full
                       MEMBER APOSTOLAKIS:  The reason being?
                       MR. KING:  The reason being that I thought
           it might be useful before we actually take the time to
           write this stuff down in a SECY paper to have some
           more discussion.  If, you know, the committee has
           different views and you want to adjust that schedule,
           we're certainly open to discussing it.  So we can come
           back to that maybe at the end of the day today.
                       MEMBER APOSTOLAKIS:  But isn't it
           typically too short a time?  If the subcommittee makes
           comments, I mean, May -- mid-May sounds like too short
           a time for any real changes in the document.  Should
           the subcommittee meeting be perhaps late April or --
           my feeling is with you guys that two weeks means
                       And I'm learning from --
                       MR. KING:  Is that a compliment or is that
           a --
                       MEMBER APOSTOLAKIS:  I'm not saying that,
           you know, blaming you for anything.  But I realize
           that, you know, there are reviews to be made and
           various offices to concur, and all that.  And two
           weeks is not enough.
                       MR. KING:  I don't think it's worth
           getting back together until we have our next public
           meeting.  I think after that would be the right time
           to get together.
                       MEMBER APOSTOLAKIS:  So, in essence, what
           you're saying is that this June letter might not be
           real.  It could be a July letter.
                       MR. KING:  That's always an option.  We
           send our paper forward and you follow up in July with
           a letter.  That's an option also.  But what we --
           ideally, we'd like to have a letter before our paper
           goes up so we can reference it in our paper.  And the
           steps to get to that point are negotiable, but I think
           we'd like to have our public meeting first and then
           get back and have some further interaction.
                       MEMBER APOSTOLAKIS:  Well, anyway, if you
           don't think it's a problem, that's fine.  But I
           thought it would be a problem.  You know, May -- mid-
           May, early June, I mean, it sounds like things are
           happening with lightning speed there. 
                       Now, you are committed to give something
           to the Commission by June 29th?
                       MR. KING:  Yes.
                       MEMBER APOSTOLAKIS:  Okay.
                       MR. KING:  That's our current commitment
           date, due date, to the Commission.
                       MEMBER APOSTOLAKIS:  And what is it that
           says that the public meeting cannot be in early April?
                       MR. KING:  There's nothing that says that,
           other than getting everybody's calendars coordinated
           and picking a time and scheduling it.
                       MEMBER APOSTOLAKIS:  Well, that would make
           everything else much easier.
                       MR. KING:  Yes.  And Mary Drouin will be
           setting that up.
                       MEMBER APOSTOLAKIS:  So if it's not early
           April, we know whose fault it is.
                       MS. DROUIN:  Alan's.
                       MR. KING:  Okay.  Slide 6.  As I said,
           we're going to talk basically about two things.  We're
           going to talk about the work we've done looking at
           risk-informing the definition of the large break LOCA,
           and then we're going to talk about other things that
           are on -- that we've considered beyond just redefining
           the large break LOCA.  And, again, these are going to
           break down into some near term and some longer term
                       And with that, I'm going to turn it over
           to Mike, who is going to talk about the large break
           LOCA redefinition area.
                       MR. KURITZKY:  Actually, before Mike takes
           over the large break LOCA redefinition, I just wanted
           to mention something up here which I hope after Tom
           has clarified things for you this isn't going to
           further confuse them.  But we had -- under this Option
           3 we had come up with a number of various options for
           risk-informing the technical requirements of 50.46 and
           the large break LOCA and associated GDCs, etcetera.
                       And we have about three of those options
           for various takes on redefining large break LOCA, and
           then another seven or so involve actual changes to
           just the technical -- the various technical
                       These three right here are the three that
           we have that all fall into the category of redefining
           large break LOCA.  And when I explain the difference
           between the three, hopefully that will further clarify
           what Tom was saying and not further muddy it up.  
                       But in the first -- when we were going to
           redefine the large break LOCA by plant, you know,
           except what we do there is a plant would then be
           permitted to define its own maximum design basis LOCA
           using leak before break and probabilistic fracture
           mechanics analyses.  It's very similar to what
           Westinghouse or NEI industry was discussing earlier
                       MEMBER KRESS:  Tell me, how would they do
           that?  That sounds like a task that I see has no
           relevance to this issue.
                       MR. KURITZKY:  Well, this one is focused
           on -- would be focused on the frequency of the break.
                       MEMBER KRESS:  Yes, but that's just a PRA
                       MR. KURITZKY:  No, it's actually even
           before that.  It's -- well, actually, the next thing
           I'm going to tell you about, actually bring more of
           the -- the carrying the risk.  This one would be on
           the frequency, and this --
                       MEMBER KRESS:  Well, what you're doing is
           using leak before break technology to -- to refine the
           frequencies of certain leak sizes, to the PRA issue. 
           I don't see its relevance to this issue of defining a
           design basis large break LOCA.  I mean, unless you're
           going to say something which I think is the wrong
           thing to do, that -- if that frequency turns out to be
           below 10-6 or some magic number, then we -- then we've
           screened all pipes or leakages bigger than that, which
           is -- which sounds like what it sounds like.  
                       But I think that's the wrong way to go,
           because the issue is really if I change this design
           basis LOCA definition, what changes will I expect to
           see in the plants?  And are those changes acceptable
           from a risk standpoint?
                       That really has nothing -- very little to
           do with the actual frequency of it.
                       MR. MAYFIELD:  But don't changes in the
           plant hinge on what size break you go --
                       MEMBER KRESS:  Oh, absolutely.  But that
           -- what I'm saying is you -- you make your rules say
           you will -- your large break LOCA will be a leak size
           specification that doesn't allow your plant to exceed
           these risk acceptance criteria, something like that
           1.174 but not exactly.
                       And then, they say -- all right.  And then
           use the leak before break technology to translate that
           leak size into a pipe size, but that's -- you know,
           that's sort of a detail.  And it doesn't have anything
           to do with the rule.
                       MR. MAYFIELD:  But it's a sticky detail to
           get to.
                       MEMBER KRESS:  Yes, it's not easy.  It's
           not easy.  I didn't mean to say that.  But it doesn't
           have anything to do with the rule, I don't think. 
           That's my point.  Other than if that helps define the
           frequency that goes into a PRA to do your calculations
           for risk.  It's useful there, too, but, you know,
           presumably we've already got that in the PRA to some
                       But that's my point.  I don't see how leak
           before break really plays much of a role here except
           in translating your leak size into pipe size.
                       MR. MAYFIELD:  I think that's -- why don't
           we go and then -- why don't we go ahead and walk
           through this, and then come back to it, Tom, if we
           don't address your issue.
                       We spent some time -- slide 8.  We spent
           some time thinking about what would go into the
           analysis, the probabilistic fracture mechanics
           analysis that might support this kind of change,
           whether you go at it to determine what would be an
           acceptable frequency or the analysis that you'd have
           to have to work backwards from at leak size to pipe
                       We spent some time thinking about what
           should go into that, what kinds of things would have
           to be considered.  First of all, we think service
           experience is the right place to start.  We'll talk a
           little bit about that.  Some analysis to predict
           piping failure frequency -- and, again, it's the same
           basic analysis, whichever direction you're going.
                       And the other one is to look at what kinds
           of failures -- other failures where the large break is
           currently a surrogate to cover those, and we'll talk
           a little bit about that.
                       We've had some prior analyses that have
           addressed these same kinds of subjects; it's
           probabilistic fracture mechanics kind of stuff.  Those
           have been presented to the committee going back to
           1985, '86, the changes to general design criterion 4;
           more recently, the risk-informed, in-service
           inspection programs.
                       Neither of those approaches were
           sufficiently rigorous to support the kind of rule
           change we're talking about here.  And I'll talk a
           little bit more about why we believe that.  We think
           that the analysis to support this kind of rule change
           -- and, again, whether it's going to the frequency or
           backing from leak size to pipe size -- that level of
           analysis ought to be at least as rigorous as what
           we're going through on the PPS rule change.
                       We think that's beginning to set a
           standard for the level of rigor that we think should
           be in the analyses to support these fundamental type
           of rule changes.
                       Can we have slide 9?
                       The prior staff study that, interestingly,
           was referenced this morning was NUREG CR-5750,
           estimated large break LOCA frequencies.  For the PWRs,
           that was a five times 10-6 kind of frequency, with a
           90 percent confidence interval running from 10-7 to 10-
           5 per year.
                       The recent experience at V.C. Summer,
           while it certainly wasn't a large break LOCA, did
           contribute to the same kinds of cracking that was
           looked at.  That would increase the best estimate that
           the staff has looked at to something on the order of
           seven times 10-6, which is certainly within the band
           that came out of the earlier study.
                       We think that overall these numbers are
           conservative, and then it gets to be a challenge of,
           well, how conservative are they?  And there are a lot
           of assumptions.  If the committee wants to go there,
           we've got the staff here that can talk to them.  But
           I think the point that I wanted to make is that the
           numbers aren't low enough that just out of hand you
           say the large break LOCA can be dismissed.  So it
           requires a little more looking than that.
                       MEMBER KRESS:  Where is that?
                       MR. MAYFIELD:  Sir?
                       MEMBER KRESS:  Where is that level?
                       MR. MAYFIELD:  I'm not going to try and
           pick it.  But when you're in the mid 10-6s --
                       MEMBER KRESS:  You know you're not there.
                       MR. MAYFIELD:  -- we think we're not
           there.  It may be one of these things where,
           collectively, the Commission would decide, well this
           is -- you know, some number is low enough; I don't
           think we have that target today.
                       CHAIRMAN SHACK:  It's okay for vessels to
           fail at that rate but not pipes?
                       MR. MAYFIELD:  Absolutely.
                       MR. KING:  Remember, the framework
           document had laid out initiating events, sort of in a
           frequency -- by frequency category.  And when it got
           down to rare events, then it had, you know, basically
           collectively we want rare events not to add up to be
           more frequent than 10-6 per year.  And any individual
           one ought to be substantially less than that.  
                       We sort of proposed a rule of thumb of,
           you know, at least a factor of 10 lower than the 10-5,
           which would say, really, to exclude something you've
           got to be below 10-6 per year frequency.  It's sort of
           the guideline we've been using in the framework
                       MR. MAYFIELD:  Slide 10, Alan.
                       We wanted to look at some of the other
           changes that we've made, places where we have accepted
           what's -- analyses that are put in a general class of
           leak before break.  These are basically probabilistic
           fracture mechanics analyses or determinations that
           derive from those kinds of analyses.
                       I mentioned the general design criterion
           4 change from 1986.  There we -- the underlying notion
           was that pipes will leak before they will break, and
           that was accepted for eliminating the dynamic effects
           associated with the big pipe fracture.
                       What that led to was the removal or relief
           from having to install pipe whip restraints and jet
           impingement barriers.  There were a few other spinoffs
           to that, but it -- those were the big issues at the
           time the rule was promulgated.
                       Subsequently, we've used these same kinds
           of arguments to get some relaxation on break opening
           time for the baffle bolt analyses, the risk-informed
           changes to the in-service inspection programs, and we
           used the same basic approach looking at the resolution
           to GSI-190 on environmental effects on fatigue a year
           or so ago.
                       Slide 11.  The traits from those prior
           applications -- they all seem to have both
           probabilistic and deterministic aspects.  Defense in
           depth, however, hasn't been challenged.  We were
           always still covered by the large break LOCA, the
           50.46 requirement.  So we weren't getting to
           fundamental changes in the plants.  Rather, we were
           dealing with some ancillary things.
                       The general design criterion 4 change,
           back when the staff made the presentation to the ACRS,
           they described the pipe whip restraints as the evil
           pipe whip restraints.  The notion was that, by and
           large, these devices were being contrary to safety.  
                       They were contributing to containment heat
           load, they were impeding access for in-service
           inspection, and if they didn't get shimmed up right
           you could actually introduce loadings that hadn't been
           previously analyzed, if the pipe managed to hang up on
           the whip restraint.  So there was an underlying notion
           that these were good changes.
                       Similarly, with the risk-informed ISI,
           there was the underlying notion that inspection
           resources could be better shifted to other piping
           systems, and there was also a -- both a quantitative
           and qualitative approach, and they gave similar
           results.  So in each of these cases there was
           something else that -- that supplemented the change
           rather than just the analysis.
                       And as I mentioned, we don't think those
           prior analyses, the probabilistic fracture, were as
           rigorous as what we would apply today in supporting a
           rule change, at least a rule change like this.
                       MEMBER APOSTOLAKIS:  But let me, again,
           say --
                       MR. MAYFIELD:  Sure.
                       MEMBER APOSTOLAKIS:  -- what would be the
           change of the rule under this option?  What exactly
           would be the change?  I mean, you are arguing that
           they don't have sufficient analytical basis.
                       MR. MAYFIELD:  But the notion here is that
           if you -- if, for example, you wanted to use this type
           of analysis to redefine the large break LOCA
           frequency, or -- or subsequently use this approach to
           determine what is an appropriate break size.
                       MEMBER APOSTOLAKIS:  But large break LOCA
           frequency -- do you mean the frequency per year?
                       MR. MAYFIELD:  Yes, sir.
                       MEMBER APOSTOLAKIS:  Wouldn't that be a
           fundamental change in the rule there?  Because the
           rule deals with the conditional stuff.  Given that
           there is a break, it shows this and this and that.
                       MR. MAYFIELD:  And if you -- yes.  Now,
           the notion is here -- I guess the notion I've been
           working to is that the approach would go along the
           lines of showing that the large break -- the frequency
           of the large break LOCA is so low that it shouldn't be
           the governing consideration.  And so now, what is the
           break size that is more appropriate to include in the
                       MEMBER APOSTOLAKIS:  But does the rule, as
           written now, it does not take into account the
           frequency of the LOCA at all?
                       MR. MAYFIELD:  Then, it assumes it's one.
                       MEMBER APOSTOLAKIS:  Does it?
                       MR. MAYFIELD:  By --
                       MEMBER APOSTOLAKIS:  It assumes it?
                       MR. MAYFIELD:  It just assumes it.
                       MEMBER APOSTOLAKIS:  But if you go this
           way, then you are really changing the argument here in
           a fundamental way.
                       MR. MAYFIELD:  Well, either that or you're
           saying that the frequency -- well, that's right.  This
           is --
                       MEMBER APOSTOLAKIS:  But that's what I
           don't understand.  That's a fundamental change in the
           rule.  The rest is the mechanics of doing it.  Now,
           what there is fundamental?  I mean, I read the rule. 
           I'm trying to --
                       MR. MAYFIELD:  Well, the idea is you're
           going to redefine the break size, the design break
           size, as something other than the largest pipe.
                       MEMBER APOSTOLAKIS:  So then you would go
           back to this idea of conditional that --
                       MR. MAYFIELD:  You're going to ultimately
           go back to this idea of some conditional break and use
           that as the design criterion.  And you would use this
           type of analysis to support defining that alternate
                       MEMBER APOSTOLAKIS:  Again, you know, it's
           not obvious to me why you have to switch back to that
           and not deal with the frequencies of the accident
           sequences of various LOCAs, and deal with the whole
                       MR. MAYFIELD:  Again, I think the same
           analysis schemes would come to play.
                       MEMBER APOSTOLAKIS:  That's correct.
                       MR. MAYFIELD:  Whether you did it with --
           just as an alternative to the existing conditional
           approach or deal with a spectrum.  The underlying
           analysis would be the same.
                       MEMBER APOSTOLAKIS:  But you would still
           deal with the frequency of the initiator that way. 
                       MR. MAYFIELD:  That's correct.  But
           don't --
                       MEMBER APOSTOLAKIS:  If we could get a
           listing of these changes, that would be very helpful
           to me.
                       MR. KING:  There's two parts you're going
           to hear.  Mike is talking about changing the
           definition of a large break LOCA, which is really what
           size pipe you assume.  There's another part we've
           looked at; it's all the assumptions that are made.  
                       Regardless of what pipe size you assume,
           there's a whole bunch of other assumptions that are in
           the way we do business today and we're looking at
           those as well, because of them don't make sense when
           you look at it from a risk perspective.  And Alan
           Kuritzky is going to talk about those, so there's two
           parts to this.
                       MEMBER BONACA:  So what you're talking
           about now is really addressing what has been presented
           this morning by the industry.
                       MR. MAYFIELD:  In part, yes.
                       MEMBER APOSTOLAKIS:  In part.
                       MEMBER BONACA:  And then, one thing that
           would be interesting, of course, in that respect would
           be if you define large break LOCA as a smaller break
           than the current one.  What kind of criteria, I mean,
           would -- is there a possibility of accepting some
           higher consequences for a large break LOCA that we
           have today?  Because this was to get done in the FSAR.
                       It would probably lead to more than 2,200
           degrees Fahrenheit temperature.  It would lead to some
           more percent oxidation.
                       All I'd like to say is that it seems to me
           that the only conflicts from the presentations we had
           this morning and now is abandoning large break LOCA,
           and that becomes almost like a severe accident
           consideration where you can have, you know, core
           damage to whatever extent.
                       Isn't there some possibility right now you
           are setting your target to a smaller break size, but
           you can also look at large break LOCA and see what --
           given the -- all the changes that a plant would make,
           you have some results that you might find as
           acceptable now.  See, that would allow you to deal
           with the fact that you're not abandoning completely
           some expectation for large break LOCA.
                       MR. KING:  Well, I think what was said
           this morning was the risk assessments will still have
           the large break LOCA in them.
                       MEMBER BONACA:  Yes.
                       MR. KING:  And the risk assessments are
           still going to need to show that the large break LOCA
           is a very small contributor to risk for this whole
           scheme to work.  I mean, if we make changes and now
           all of a sudden the large break LOCA is a high
           contributor to risk, then we haven't done our job.
                       MEMBER KRESS:  I think that's true, that
           if it came out to be a high contributor to risk for
           specific plants, then you need to consider it in your
           design basis.  But I don't think the inverse is true,
           that if it comes out to be a low contributor to risk,
           that doesn't necessarily mean that makes it a bad
           design basis.  
                       And the reason for that is when you invoke
           and impose a design basis, you end up with certain
           design features and certain procedures and certain
           things that help control the total risk, not just for
           that set of sequences but for all of the other
           sequences involving LOCAs, and so forth.  And you want
           that total risk to be within acceptable limits.  
                       So, you know, my perspective is your
           Option 3, if you look at -- if I go from -- to a
           specific leak rate or a specific size different than
           this, what changes will the plants make?  And are
           those changes acceptable from a risk standpoint?  And
           that, to me, seems to be the only rational way to view
                       MR. KING:  I agree.
                       MEMBER KRESS:  Not deal with, is the large
           break LOCA a risk contributor?  Maybe it is, maybe it
           isn't.  You know, if it is, you have to deal with. 
           But if it's not, I still don't think it's the right
                       MR. KING:  No, I agree with everything you
           said.  The large break LOCA probably is a surrogate
           for some other things that you don't have to worry
           about because you take care of it through dealing with
           the large break LOCA, although that has to be
                       MEMBER KRESS:  Okay.  
                       MR. MAYFIELD:  Which I think is at least,
           in part, the message here is that this is perhaps a
           tougher analysis than has been thought about. 
                       And that -- on Slide 12, the notion here
           is, again, we think that we've started setting some
           guidelines on what is an appropriate level of rigor in
           these analyses, based on what we're doing for the PTS
           rule.  And the presumption here is that we're going to
           actually be successful with the PTS rule.
                       You can look, of course, at transients, at
           thermal-hydraulic response, and so on.  There are a
           couple of these that get to be more interesting if you
           were actually going to try and do this for piping. 
           The flaw distribution is one that gets significantly
           more challenging.
                       We've actually done more work on flaw
           distributions for vessels than we have for piping. 
           The other one that we haven't gotten into for these
           kinds of analyses are the uncertainty analyses, and to
           do that rigorously dealing with both epistemic and
           aleatory uncertainties.  
                       We think that would become a significantly
           more challenging approach for this piping analysis
           than it is for the vessel.  There are more degradation
           mechanisms, there are more unknowns, there are more
           model uncertainties, and on and on.  It gets to be a
           much tougher challenge than it is for the vessel.
                       If we can have Slide 13, Alan.
                       The next several slides I don't propose to
           go through in any detail.  They are more for your
           information.  They're the kinds of things that we
           think would have to be treated, some examples of
           issues that we think haven't been dealt with very
           well.  The analyses themselves would have to deal with
           both the initiation of subcritical cracking, the
           subcritical crack growth, leak rate detection under
           normal operating loads, and the fracture during upset
           loads.  Those are just the kinds of analyses that have
           to be dealt with.  
                       The main inputs to the probabilistic
           fracture, the material property input, the crack
           morphology -- what the crack surfaces look like -- the
           loads under normal and transient conditions, the flaw
                       On Slide 15, we need to deal with the
           current and as-yet unknown mechanisms.  This is
           something, how do you know what hasn't happened yet,
           and that's part of the speculation that gets to be
           challenging in doing this.  
                       There are some kind of notable examples of
           things that we didn't think were likely.
                       MEMBER WALLIS:  It's not just what hasn't
           happened.  It's what you --
                       MR. MAYFIELD:  It's what we don't know.
                       MEMBER WALLIS:  -- are not yet aware of.
                       MR. MAYFIELD:  Yes.  Exactly.  So there
           are some examples here of the kinds of things that
           have caught us a bit by surprise in the past, the most
           recent one perhaps being the primary water stress
           corrosion cracking in the Inconel 182 welds.  It's not
           that we didn't know that material would crack.  We
           just didn't think that the loading and conditions were
           right for it to crack in that particular application.
                       There are a host of things on Slide 16
           that go into the leak rate analyses.  So if we really
           wanted to follow Dr. Kress' suggestion and take a leak
           size and work backwards to a pipe size, that gets to
           be a -- first of all, you can get a range of pipe
           sizes depending on the crack size and loading.  So it
           -- there would be a fair bit of uncertainty to deal
           with in that analysis.
                       But things like residual stresses come
           into it, the pipe to system boundary conditions, are
           you getting some restraint of free thermal expansion,
           some restraint of bending in the pipe, crack face
           pressures, some things that haven't been included. 
           And it -- as you work backwards from a leak size to a
           pipe size, those things get to be important and you
           change from a conservative approach to a non-
           conservative approach, just depending on the direction
           you're going.
                       MEMBER KRESS:  Would this analysis also be
           time-dependent, then?
                       MR. MAYFIELD:  Absolutely.
                       MEMBER KRESS:  So that's a factor we never
           really --
                       MR. MAYFIELD:  Yes.
                       MEMBER KRESS:  -- had in this design basis
                       MR. MAYFIELD:  That's correct.  That's
                       On Slide 17, the fracture mechanics
           analyses, this would go to an elastic plastic fracture
           rather than the net section collapse or limit load
           kinds of approaches.  We have historically assumed
           some idealized through wall circumferential cracks,
           nice regularly-shaped things.  But if the subcritical
           cracking caused large surface cracks, long on the
           inside surface and relatively short on the outside
           surface, it introduces another complication in either
           direction in the analysis.
                       You'd need to look at things like the
           earthquake rate -- loading rate effects on material
           properties.  These are not dynamic loading rates in
           the classic sense, but there is a phenomena known as
           dynamic strain aging that at these loading rates does
           get to be an issue.
                       One of the interesting things that we've
           discovered from some of our experimental work at
           Battelle is that if the bending plane happens to be
           different than the normal -- the primary plane for the
           crack, you can get some significantly different
           fracture behavior, and that is physically possible. 
           We've seen it.  So that gets to be an interesting
           twist to the analyses.
                       On Slide 18, the material property input,
           these are normal kinds of things that you would hear
           about, and I think you've heard about them before. 
           The difficulty now comes in quantifying them and
           quantifying the distributions on them into the
           analysis and to feed into the uncertainty analysis.
                       This is something that we met with the
           committee and talked about just on the fracture
           toughness for the vessel steels.  And that, in and of
           itself, is fairly complicated.  This expands
                       On Slide 19, the loads, looking at normal
           operating versus upset loadings, and looking at the
           actual stress levels versus the design basis levels --
           and that got to be an important consideration when we
           were looking at the environmental effects on fatigue,
           to not just roll in the design basis stresses but to
           actually come up -- try to come up with the true
           operating stresses.  And in some cases they were
           substantially lower.
                       There are some thermal gradient effects
           that I guess I hadn't been aware of until a
           conversation that was being held on the steam
           generator tube ruptures, some helical thermal gradient
           in the hot leg.  How much that changes with time, is
           it a consideration, it's not something we have rolled
           into the previous analysis; it's something that ought
           to at least be considered here.  Whether it has to be
           incorporated rigorously is something you'd have to
           decide as you went along.
                       The initial flaw distributions -- again,
           this is something that will be even more complicated
           for the piping evaluation than it was for the vessel
           because of the nature of the loadings, the potential
           for the environment to expand the number of flaws, the
           way you would have to treat the potential for pre-
           service or fabrication-induced flaws, to pick up and
           grow during operation, which is not something that we
           have seen or are able to predict in the vessel
                       So, again, the piping is a more difficult
           analysis to perform.
                       We've talked about other sources of large
           breaks where the large break LOCA or the -- at least
           the failure of the big pipe is a surrogate for these
           things.  Losing the steam generator manways, the
           potential for those few plants that have loop stop
           valves, the potential for losing the bolts that hold
           the bonnet on.  We've seen in some smaller valves some
           valve body cracking; would that be an issue here?
                       Then, there is the subject of indirect
           sources of pipe failure, and the notion here is moving
           heavy loads inside the containment during power
                       In the work that was done by -- at
           Lawrence Livermore in support of the GDC4 changes,
           these indirect sources of pipe failure -- actually,
           you got up to where that was the dominating
           contributor to pipe failure frequency.  So it's
           something that needs to at least be considered here.
                       MEMBER BONACA:  Moving heavy loads, the
           power operations, is that containment?
                       MR. MAYFIELD:  Well, at any rate, in
           summary on Slide 22, the service data alone don't
           appear to us to support eliminating a large break LOCA
           without some further evaluation.  The data, such as
           they are, with some -- potentially with some limited
           additional analysis would appear to be sufficient to
           support some other types of changes.
                       The probabilistic analyses to support
           eliminating the large break LOCA we believe would have
           to be significantly more rigorous than what we've done
           in the past, both from the staff as well as the
           industry.  And we think that active degradation of the
           piping is not the only consideration.
                       The analyses would have to consider other
           breaks, and they'd have to consider things like weld
           repair history to make sure we capture potential for
           other degradation mechanisms.
                       MR. KING:  Okay.  Now Alan Kuritzky is
           going to talk about putting the redefinition of the
           break size aside, what other things that we looked at
           in terms of potential changes in risk-informing 50.46.
                       MR. KURITZKY:  Yes.  As I mentioned
           earlier right before Mike began speaking, there was
           about 10 different options we looked at during this
           program.  The first three all involved various -- you
           know, different variations of redefining the large
           break LOCA, and now here we have seven more options. 
           And these look more specifically --
                       MEMBER APOSTOLAKIS:  Again -- I'm sorry,
           maybe it's not a good day for me.  Why are they risk
                       MR. KURITZKY:  Why are they risk informed? 
           Well, because as I go through these items that are on
           this list I'll explain the risk implications and what
           risk aspects led us to come up with these as options.
                       MEMBER APOSTOLAKIS:  And you have criteria
           for deciding that these aspects are good or bad?
                       MR. KURITZKY:  Well, what we're using
           right now, as Tom mentioned before, is based on our
           framework document.  We have about a 10-6 roughly for
           something that may be low enough that it's, you know,
           considered to be a rare event and may not need to be
           considered.  And so that's kind of like a threshold.
                       MS. DROUIN:  That's only one threshold. 
           Also remember that one of our ground rules under
           Option 3 is that when you look at the analyses, if the
           analyses are conservative, we see that in a risk arena
           you want to be realistic.  So some of the options
           might -- it may have no relationship to the
           quantitative guideline.  It's because there is excess
           conservatism, and our ground rules -- one of the
           ground rules in the framework was to be realistic.
                       MEMBER APOSTOLAKIS:  But, again, we are
           talking about a fleet of 103 units.  So, I mean if I
           want to delete loss of offsite power consideration,
           that may have different impact on CDF on different
           units.  On what basis do I decide to delete?  By the
           largest impact or when we --
                       MEMBER KRESS:  The average or --
                       MEMBER APOSTOLAKIS:  Yes.
                       MEMBER KRESS:  On a specific basis?
                       MEMBER APOSTOLAKIS:  Yes, I don't know. 
           You see, that's where I get confused.
                       MEMBER KRESS:  Yes, I had that same
                       MR. KING:  Or you set some criteria.
                       MEMBER APOSTOLAKIS:  So we don't have them
                       MR. KING:  We have not reached the point
           where we've nailed down every detail of what we're
           going to propose.  What we're talking about are
           certain areas that we think make sense for -- for
           looking at it a little further and possibly going
           forward with recommendations to the Commission.  
                       Just take the first one -- simultaneous
           loss of offsite power at the same time the large break
           LOCA occurs.  You know, you can use frequency
           information and risk information to say that that
           assumption is pretty -- pretty low in terms of
           frequency and pretty low in terms of risk --
                       MEMBER KRESS:  Well, let me --
                       MR. KING:  -- for the large break LOCA.
                       MEMBER KRESS:  Yes, let me tell you what
           bothers me about that.  Let's go back to the framework
           document where you have these categories and ranges of
           frequencies for basically specific sequence sets.
                       Now, if I look at, say, a large break LOCA
           of a given size, and it fits into one of those
           categories, that's the wrong way to use that framework
           document.  That's not what it was intended for.  What
           you need to say is, "We've defined this as my large
           break LOCA."  What does it do to the frequencies of
           all the sequences that go into the PRA, and how does
           this shift them all with respect to that framework
           document?  And is that total shift --
                       MEMBER APOSTOLAKIS:  Which means look at
           some global method.
                       MEMBER KRESS:  Some global method, yes.
                       MEMBER APOSTOLAKIS:  Like the CDF.
                       MEMBER KRESS:  Well, like the CDF.  Well,
           not exactly global because I think defense in depth
           gets involved in terms of this allocation that you
           have.  I think that's a defense in depth concept.  So
           that's one way you bring that in.
                       But I think just to say large break LOCA,
           if it's this size, that particular sequence provides
           this contribution that we have in this box, is the
           wrong way to use that framework.
                       MR. KING:  I think you have to do both. 
           I think you have to start somewhere, and you have to
           say if large break LOCAs are very low frequency, then
           maybe we ought to consider not calling them design
           basis accidents anymore.  Then you have to go and
           look, well, what does that do to my risk for the
           plant?  And if it turns out that that drives other
           things up, then maybe you don't want to do that.
                       If it turns out it doesn't drive other
           things up, that it really is a very low risk type of
           item --
                       MEMBER KRESS:  I think that's the key
           element right there.
                       MR. KING:  Yes, I agree with you.
                       MEMBER KRESS:  I think that part of it --
                       MR. KING:  But you've got to start
                       MEMBER KRESS:  Yes.  Yes, because you
           can't really do that other part yet, the second part,
           the important part, the risk -- and it's awfully hard
           to do.  You probably don't have the capabilities of
           doing that just yet.
                       MR. KING:  Well, I think you have the
           capabilities.  I think, you know, you have to take
           some time and some, you know, effort to do that.
                       MEMBER KRESS:  Each plant-specific PRA
           would have to be -- would have to decide what changes
           in a plant are made and see how that impacts the PRA,
           and do it on a plant-specific basis, and average it
           out or add it up  or something.  It's not easy.
                       MR. KING:  Everything we're talking about
           today, not just the break size, there is the question
           of how much can you do generically, and how much do
           you have to do plant-specific?
                       MEMBER KRESS:  And that's --
                       MR. KING:  And the question applies to
           everything we're talking about.  And we haven't nailed
           down where you draw that line yet, but we recognize
           that that line has to be drawn somewhere.
                       MEMBER APOSTOLAKIS:  Now, what is the
           Commission's attitude towards Option 3?  Have they
           approved it or what?  I don't remember.
                       MR. KING:  Option 3 was approved, yes, a
           couple of years ago.  Remember, 50.44 was the first
           one that came out of that, and this is the second one.
                       MS. DROUIN:  It's in the SRM in response
           to SECY98-300.
                       MR. KING:  Yes.
                       MEMBER KRESS:  Yes, 50.44 was a breeze. 
           That's one of the ones that --
                       MEMBER APOSTOLAKIS:  Mary, you live with
           those numbers.  We come here once a month.  You know,
           SRM does this and that.  It's not as alive to me as it
           is to you.
                       MR. KING:  Why don't you let Alan talk
           about these, and then we can come back and maybe talk
           about some of these generic questions.
                       MEMBER APOSTOLAKIS:  Okay.
                       MR. KURITZKY:  Okay.  One of the first
           things that we just talked about -- just momentarily
           about the simultaneous loss of offsite power
           assumption.  One of the ways that we can envision
           something like that playing out is -- is if the NRC
           were to come up with some acceptable frequency
           distribution for large break LOCAs, Tom already
           mentioned that in NUREG 5750 we have -- or I guess
           Mike may have mentioned that we had a range from 1E-7
           to 1E-5 for PWRs for large break LOCA.
                       If 1E-5 is your upper bound, you could say
           that's the upper bound for large break LOCA and you
           can show that your conditional loss of offsite power
           -- you know, loss of offsite power frequency is on the
           order of 10-2, 10-3, and that could put you below some
           threshold.  And you may decide that that doesn't need
           to be one of your design basis considerations, you
           know, assuming loss of offsite power with the large
           break LOCA.
                       Numbers like that have already been -- as
           part of the resolution I think of generic issue 171,
           there was some look into the conditional loss of
           offsite power probabilities and --
                       MEMBER KRESS:  As a function of time after
           the LOCA?
                       MR. KURITZKY:  No, it was just a -- it was
           just given that you had --
                       MEMBER KRESS:  You may have one eventually
           within --
                       MR. KURITZKY:  Right.  In fact, what was
           driving the initial failure probability was the
           starting of the large ECCS pumps.
                       MEMBER KRESS:  Okay.
                       MR. KURITZKY:  And so that was in the
           range I think for PWRs about 1.1-something, 10-2, and
           for BWRs I think it was 6-2.  So we can see that the
           numbers -- given the large break LOCA frequencies, and
           those numbers put you somewhere in that -- in that
           threshold range.  It was something that may be
           feasible, but --
                       MEMBER KRESS:  Once again, I fail to see
           the relevance of the, say, 10-7, because what I was
           saying is if I want to drop the loop, simultaneous
           loop LOCA rule, why does that change?  Why do people
           want to change?  And does that change the risk status? 
           You know, that's irrespective of the frequency.
                       MR. KURITZKY:  And I would have to -- and
           if someone were to come through and supply the
           justification why they feel their initial loss of
           power is -- why they would make a change, then
           whatever plant change they would then want to --
                       MEMBER KRESS:  You know --
                       MR. KURITZKY:  -- make because of it they
           would have to justify on a risk basis, and it could
           impact many things besides just the large break LOCA. 
           They have to show that the delta risk is acceptable,
           you know, maybe per Reg. Guide 1.174 or --
                       MEMBER KRESS:  But, see, my point is I
           don't see that you can do ahead of time a look at the
           conditional loop, for example, and say you come up
           with a frequency of 10-8 or 10-7 or 10-9 even.  I don't
           see that it tells you anything that's useful in
           saying, "Okay.  We'll do away with that part of it." 
           I don't see that that's helpful to you.
                       MR. KING:  I don't see why you don't see
           it's helpful.  I mean, if you're making assumptions
           that are rather remote in likelihood, does it really
           make sense?  And particularly if it's causing the
           plant --
                       MEMBER KRESS:  There may be some very
           specific things just related to that.  I don't want to
           be, you know, completely on one side of that.  There
           may be some very specific things relating to that that
           has no impact on anything else, and, in fact, may have
           a negative impact that you could obviously change.
                       But I think just to use it as an ultimate
           reason is --
                       MR. KING:  But if it's causing the diesel
           generators to have to start up very quickly --
                       MEMBER KRESS:  Well, there may be other
           reasons that you want the diesels to start up quickly.
                       MR. KING:  There may be.  There may be
           other things that would catch -- I agree with that.
                       MEMBER KRESS:  You can't just throw it
                       MS. DROUIN:  No.  And if you go back to
           the framework, nothing is ever thrown away or added in
           just because of a number.  And that's where we bring
           in this -- we bring in the defense in depth and we
           have six things that we had identified there.
                       Also, another part of the framework is
           that before -- one of the other ground rules before we
           delete something, we have to go in and go back and use
           50.44 as an example, look at all of the tentacles and
           where it would have impact.  And that has to be
           brought in, and that's all part of the ground rules
           under which we make the decisions.  
                       So it's not just, oh, well, there's a
           number and it's below it, so we can throw it away. 
           It's not -- that's not what we do.
                       MR. KURITZKY:  And just to follow -- just
           in direct response to what you said, Dr. Kress, in the
           case of if we were going to relax -- you know, the
           start time had to be relaxed, then we would let -- one
           of the things we would need to consider is, do we need
           some other type of design-based accident that -- that
           governs diesel start time?  Because there may be some
           other parameters that need to be looked at.  So,
           you're right.  That would have to be considered.
                       Okay.  The second one on there is the
           excluding highly unlikely combinations of large break
           LOCA initiators and single -- it's going to fall along
           the same lines of what we just talked about -- loss of
           -- initial loss of offsite power.  It would run in the
           same -- have that same --
                       MEMBER KRESS:  Yes, it's the same issue.
                       MR. KURITZKY:  So whenever fair, the same
           thing holds.
                       Again, so that is something we would
           consider.  There would be a threshold, and we'd have
           to consider other aspects, too, what would be the
           overall risk impact of changes associated with that.
                       The next bullet is to look at the
           conservatisms in Appendix K and decide whether or not
           there are certain conservative models in Appendix K
           that we feel can be replaced with more realistic
           models or assumptions.
                       MEMBER KRESS:  I see that as sort of a
           separate issue.  I don't know -- I don't see that's
           related to this particular issue.
                       MR. KURITZKY:  Only in the sense that
           we're looking to make things more realistic.
                       MR. KING:  Yes.  Isn't risk-informing also
           being more realistic?  I mean, the risk analysis is
           supposed to be a realistic analysis.
                       MEMBER KRESS:  Well, the risk analysis is
           supposed to be realistic.  But Appendix K doesn't
           necessarily have to be realistic.  It can be risk-
           informed and be very --
                       MR. KING:  If they're going to be risk-
           informed, that to me also implies we want to be
                       MEMBER WALLIS:  Is the idea that something
           like the peak clad temperature might be a function of
           the risk?  That you might allow a 2300 if it's less
           likely or --
                       MR. KING:  Well, it depends.  Is the peak
           clad temperature 2200?  Is that a very conservative
           number?  Is that a --
                       MEMBER WALLIS:  Even if it's conservative. 
           Does it -- if it's a very likely event, you might want
           some more conservatism.
                       MR. KING:  Yes, I agree with that.  That's
           the margin issue.
                       MEMBER WALLIS:  So you'd reexamine on the
           basis of risk.
                       MR. KING:  Yes.
                       MR. KURITZKY:  In fact, the last bullet up
           there is -- that's pretty low on the screen for you
           guys, but it's modify the ECCS acceptance criteria. 
           It's another one that --
                       MEMBER WALLIS:  We got that.
                       MR. KURITZKY:  Okay.  And then, actually,
           the next three bullets all are things that are
           associated with the best estimate calculations.  And
           just various ways of -- well, in the first case, they
           would be using -- we would be considering, you know,
           would it be possible to use a distribution of break
           size allocation as input to the best estimate file and
           propagate it just like we do with other parameters. 
           Therefore -- 
                       MEMBER WALLIS:  It's just one of the other
                       MR. KURITZKY:  Right.  And, in fact, you
           have the very tail end of the LOCA, the very large
           break -- you know, it's driving what you're getting
           out because it's --
                       MEMBER WALLIS:  It's not --
                       MEMBER KRESS:  Sorry.  Once again, I'm a
           little bothered by that one because to me the break
           size or, alternatively, the leak rate was the
           independent variable.  And you don't normally attach
           uncertainty distributions to your independent
           variable.  You're looking at something that results
           from that independent variable, which is a specific
                       And you put the uncertainties on the
           things that give you the result, and that one -- I
           just don't quite understand what that one is saying to
                       MEMBER WALLIS:  I don't have any problem
           at all admitting I'm uncertain about the break size
           and trying to put it into the analysis.
                       MEMBER KRESS:  Well, sure you're uncertain
           about the break size if you're going to go in and
           decide on a frequency of a given break size to feed
           into a PRA, as part of PRA.  But --
                       MEMBER WALLIS:  You don't think it's part
           of the thermal-hydraulics?
                       MEMBER KRESS:  Oh, I'm sorry.  I think
           it's part of this element of fracture mechanics that
           Mike said when you go from a given leak rate to decide
           what kind of a break size that relates to, it's
           certainly a part of that.  I didn't mean that.  But to
           me it's not part of risk-informing the 10 CFR 50.46. 
           It's a -- it's how you implement that risk-informed
           version.  Once you go back to -- if you're going to go
           so -- say, now what break size can I live with?
                       MEMBER WALLIS:  I'm just sitting here
           looking at all of these things and thinking of how
           much work it would take to do them.
                       MEMBER KRESS:  Oh, this is -- this looks
           like a lot of work.
                       MR. KING:  This is a list of things we've
           considered.  What you're going to hear is how we split
           those up as to what we think is reasonable to go
           forward with in the short term and which ones need
           more work.  This is one of the ones that falls on the
           "more work" list.  It's not anything we're to the
           point we feel comfortable to go forward with now.
                       MR. KURITZKY:  These are all the things we
           -- actually, we've had these on the table for probably
           close to a year now, and we've presented them at
           various public meetings, so -- and in the last --
           well, the next two there as far as the best estimate
           calculation, the fifth bullet, meet improved
           efficiency of the calculations using improved
           statistical sampling methods like Latin Hypercube
           sampling to try and make it a little more efficient.
                       And the sixth one was one we had
           considered the possibility of having the NRC approve
           certain uncertainty increments that would then be
           input, and licensees could then just do their best
           estimate calculation without having to necessarily do
           all of the costs of the uncertainty analysis.  There
           would be some fixed offer or safety margin or
           something that would be associated with a
           predetermined uncertainty increment.
                       Again, these are just things that we had
           put out on the table for possible consideration.
                       And the last one was modifying the ECCS
           acceptance criteria for looking at peak cladding
           temperature, the oxidation, and determining whether or
           not there is any better way, you know, to -- in other
           words, of those acceptance criteria, is there a better
           way to handle it?
                       MEMBER WALLIS:  About like rewriting the
           works of Shakespeare.
                       MR. KURITZKY:  In our spare time.
                       MEMBER WALLIS:  Spare time.
                       MR. KURITZKY:  Okay.  Based on the --
           those are some of the options we had thought about. 
           Of those options, there was a few that we felt in the
           -- in the short term we felt we could establish the
           feasibility of.  And when we say "short term" we mean
           in order to get something in the Commission paper by
                       And the ones that we thought we had a fair
           shot at establishing the feasibility or determining
           the feasibility of are the large break LOCA, the
           simultaneous loss of offsite power, large break LOCA
           assumption, and that effects -- these, in fact, don't
           affect -- I think none of these actually affect 50.46
           -- the actual 50.46 itself, but rather Appendix K or
           some of the GDCs.
                       Also, we have the single failure
           assumptions just like we talked about in the previous
                       MEMBER WALLIS:  Associated with the large
           break LOCA.
                       MR. KURITZKY:  Like we have unlikely
           combinations.  And an additional thing with the single
           failure assumption is -- is to pursue maybe the use of
           some type of risk-informed approach consistent with
           the framework that would us to determine how and where
           we might want to change the single failure criteria. 
           But that's a little broader than just looking at the
           single failure associated with that large break LOCA.
                       Reducing decay heat conservatism --
           Appendix K is also one we feel we might --
                       MEMBER WALLIS:  That might be one of the
           easiest ones.
                       MR. KURITZKY:  That's what we like to
                       MEMBER WALLIS:  Well, is that your
           statement?  Isn't this one of the easier ones?
                       MR. KURITZKY:  That depends who you ask.
                       MEMBER WALLIS:  Oh, okay.
                       MR. KING:  We can have Norm Laubin explain
           that to you, but we've done some work on it, and it's
           not as easy as you may think.
                       MR. KURITZKY:  A lot of these are -- some
           of them appear easier, and then if you ask certain
           people there are reasons why they don't think they're
           that easy, so it --
                       MS. DROUIN:  A lot of it -- why it didn't
           get so easy is that, as you see, just the effects of
           it and how far you have to dig down and the things
           that it affects is sometimes not as straightforward. 
           And as you start uncovering all these layers it just
           becomes a little bit more complicated than you thought
           at the onset.
                       MR. KURITZKY:  And another one, actually,
           is not on this slide, but we are also kind of tossing
           about is the possibility of some relaxation in the
           break opening time.  Right now, I think it's specified
           in the standard review plan, Section 3.6.2, as a one
           millisecond break opening time.  And we're considering
                       MEMBER WALLIS:  If it goes to two
           milliseconds, it won't make much difference.
                       MR. KURITZKY:  Or one and a half.
                       Or maybe something else along the lines of
           20 milliseconds or something, and one of the areas
           that they may have significant benefit is for the
           barrel -- the baffle form of bolt.
                       MEMBER WALLIS:  On the loads, is it when
           you get sort of --
                       MR. KURITZKY:  Yes.
                       MEMBER WALLIS:  -- propagations and things
           that --
                       MR. KURITZKY:  Yes.  Lastly, we have up
           there consider enhancements based upon risk insights,
           and then we want to look through the risk insights and
           see if there -- if it indicates that there may be any,
           you know, related safety concerns.
                       MEMBER WALLIS:  What do you mean by
           "enhancement" here?
                       MR. KURITZKY:  Enhancement would be if
           there is a safety concern that is indicated by the
           risk insights, is there something we feel needs to be
           beefed up?
                       MEMBER WALLIS:  Oh, beefed up.  Okay.  It
           means toughening up the regulation.
                       MR. KING:  An example is maybe automatic
           switchover to ECCS recirculation for those plants that
           don't have it.  Is that something the risk insights
           are telling us ought to be in place?  You know, that's
           an example of what we're looking at.
                       MEMBER WALLIS:  It makes sense that you
           should look at both directions, if you can improve
           safety based on risk insights.
                       MR. KURITZKY:  Right.  And then our
           Option 3 framework.  That's part of the Option 3
                       Okay.  Some of the benefits that we've
           identified with these near term -- these possible
           near-term changes, and as they relate to the agency's
           performance goals -- to maintain safety, we feel that
           these changes would help to maintain safety.  In fact,
           there may even be some improvement in safety.  
                       Diesel generator liability, as was
           discussed earlier today, is one area where there may
           be some improvement in safety.  We would maintain the
           elements of defense in depth so there would be no
           degradation there.  
                       And, again, safety system reliability
           would either -- we would -- there would be no
           significant decrease based on these changes, and, in
           fact, in some cases there may be an increase,
           depending on how that -- how we would address the
           single failure criteria.  There's actually some places
           where there may be enhanced system reliability.
                       Also, these changes -- these near-term
           changes would make the PRSA activities more effective,
           efficient, and realistic.  Particularly in the
           realistic arena we would have more realistic
           assumptions in the DBAs.  We'd have, you know, maybe
           more realistic assumptions for Appendix K, and so that
           would -- in keeping with that second goal.
                       MEMBER APOSTOLAKIS:  How would you decide
           whether key elements of defense in depth are
           maintained?  Is that a judgment call, really?
                       MR. KURITZKY:  Well, I guess the actual
           elements themselves we're going to take from doing the
           framework document, which is fairly similar to the one
           that is in Reg. Guide 1.174.  And you would -- I guess
           it is -- I mean, it's necessarily a qualitative
           analysis.  I mean, there may be some qualitative
           pieces to it, but it's going to be some kind of
           judgment qualitative decision that you're not
           degrading anything.
                       MR. KING:  Do you still have prevention
           and mitigation?  Do you still have sufficient, you
           know, redundancy based upon the reliability of the
                       MEMBER APOSTOLAKIS:  You can look at the
           single failure criterion and you'll decide to abolish
           it.  You will rely on some quantitative analysis to
           show that you have not really degraded the --
                       MR. KING:  Some, for example,
           probabilistic definition of the failure criteria. 
           Maybe it results in not having to assume a single
           failure.  Maybe it results in having to assume a
           multiple failure, depending upon the system
           reliability and the break you're looking at.  So it
           can work both ways again.
                       MEMBER WALLIS:  Some people might argue
           that certainly large break LOCA is the biggest thing
           that could ever happen.  Is that kind of element -- it
           has an element of defense in depth to it.  I mean,
           that you -- because you're uncertain, you look at the
           extreme case and defend against that?
                       MR. KING:  Sounds like pre-TMI
                       MEMBER WALLIS:  Isn't that the sort of
           argument that was originally used in support of the
                       MR. KING:  Yes, I think it probably was. 
                       MEMBER WALLIS:  Was that defense in depth
           or is that something else?
                       MR. KING:  I'm not sure I'd call it
           defense in depth.  You may argue, well, that gives you
           a margin because you know you can handle this big
           break.  Therefore, you can handle anything smaller.
                       MEMBER WALLIS:  Defense in depth in depth
           is what you went to when you were uncertain, because
           you sort of have a nagging feeling that if something
           were to happen you're not quite certain about, then
           you --
                       MR. KING:  Defense in depth to me is
           different ways to accomplish the same function. 
           Again, you know, just assuming the large break covers
           everything that --
                       MEMBER WALLIS:  The containment is there
           for the same sort of reason.  But there are different
           ways to perform the function that containment
           performs.  But because you're uncertain you put it
           there anyway.
                       MR. KING:  Okay.
                       MR. KURITZKY:  And the last thing here we
           have the performance goal reduce the unnecessary
           regulatory burden.  And the near-term changes that we
           listed previously should help in a number of these
           areas that are listed up there.  Extension of the
           diesel generator start and loading time, which was
           discussed already.  That's one of the big issues.  
                       In fact, we have some cost information
           that was provided to us from industry which shows that
           extending the diesel generator start and loading time
           could, in fact, save upwards of $400,000 to as much as
           $1.2 million per plant per year.  The big swing there
           is whether or not it's on the critical path outage.
                       Also, relaxation of some AOTs or, in fact,
           even removing equipment from the tech specs, like the
           accumulator, which, again, I think we had some data
           from industry that shows that could save upwards of
           around $17,000 per plant per year.  And additional
           analytic margin for plants that are limited by
           Appendix K right now.
                       It's only going to be some plants, and
           exactly how they're limited and what -- unnecessary
           regulatory burden, we feel, again, is going to be very
           plant-specific.  But it's certainly one area where
           there's some potential.
                       Okay.  We recognize that, obviously, as we
           move forward with these short-term potential changes
           that there's a number of implementation issues that
           will have to be addressed.  And we have them listed I
           think on the next two slides.  We don't need to go
           into a lot of detail on them because there is stuff
           that we can still -- the staff needs to still think
           about the nuances of them, but basically they're many
           of the similar things that we've discussed already.
                       If we're going to use something like a
           combined reliability threshold or a frequency
           threshold for the San Mateas LOOP assumption or the
           single failure criterion, then we're going to need to
           have some kind of frequency of the large break LOCA
           distribution.  And since we can't make a convenient
           cut necessarily at the six inches or wherever a PRA
           says a large break LOCA is, we would actually need to
           have that distribution across all pipe sizes or all
           affected break sizes.  That's one thing we'd have to
           -- we have to consider.
                       When going to the San Mateas LOOP
           assumption there are a number of concerns, at least
           from doing something generically because there are a
           lot of plant-specific aspects.  Plants have different
           types of procedures and designs to handle loss of
           offsite power, particularly delayed loss of offsite
           power concerns, and so there may be, you know, some
           significant work that may have to be done to make sure
           that that's feasible.
                       Again, as we mentioned before for the
           single failure criterion, we may consider whether
           there's some kind of risk-informed replacement for
           what will be combined initiator frequency and failure
                       One of the issues we want to keep in mind
           as we move forward is that we want to try and utilize
           a performance-based approach wherever possible.
                       MEMBER WALLIS:  How do you apply that to
                       MR. KURITZKY:  Well, I think that
           performance-based to my mind -- maybe in the example
           we've talked before about the conditional loss of
           offsite power where if you have some kind of curve for
           the -- you know, for the frequency of the large break
           or breaks, then the utility may come in and try and
           demonstrate that there conditional loss of offsite
           power probability is of a certain value.
                       MEMBER WALLIS:  It also would involve
           perhaps utilities showing that their ultrasound method
           for detecting cracks really could detect cracks.  Is
           that performance-based, too?
                       MR. KURITZKY:  I leave that one to Mike.
                       MEMBER WALLIS:  They would just go through
           the ritual, but it actually works.
                       MR. MAYFIELD:  There is clearly a
           performance-based element in that, yes.
                       MR. KURITZKY:  Delayed LOOP we just talked
           about.  Just a couple of the issues there -- the
           double sequencing and the degraded voltage issues are
           the ones that we have to kind of do some more thinking
                       And also, the impact other modes of
           operation and potential accidents.  Low power
           shutdown, for example -- whatever we do for --
           anything for 50.46 or large break LOCA, we have to
           make sure that while we're thinking primarily of this
           operation, we've got to make sure that for low power
           shutdown modes we're not going to do anything dumb,
           not giving anything away, we need to be conscious of
                       MEMBER APOSTOLAKIS:  Are you going to be
           able to do that without very good risk assessments for
                       MR. KURITZKY:  There are limitations that
           we have to deal with.  I mean, that's obvious.  And
           even for operation for --
                       MEMBER APOSTOLAKIS:  What does it mean
           "limitations"?  So how would you do it?  Would you be
           more concerned with it?
                       MR. KURITZKY:  That's one possibility. 
           You have to be -- I mean, where there's uncertainty,
           you go to conservatism if you can't address certain
                       Okay.  Some things aren't --
                       MS. DROUIN:  We don't have an answer to
           that, George, at this point of how we're going to deal
           with it.
                       MEMBER APOSTOLAKIS:  All right.  
                       MR. KURITZKY:  Okay.  As Tom mentioned
           before, there is also some things that we're thinking
           about more for the longer term, other changes to
           10 CFR 50.46 or associated GDCs.  
                       One is to redefine large break LOCA.  As
           was discussed previously, that goes back to the first
           three options that we talked about right before Mike
           spoke and also what industry spoke of this morning. 
           We would want to continue working with industry on the
           scope and depth of what work would be entailed.
                       MEMBER WALLIS:  I've been waiting to ask
           you the question, and it seems to me your presentation
           and the industry presentation don't have too much
                       MR. KURITZKY:  Where the overlap would
           have been is those first three options or parts of
           this first step which we've kind of -- we skipped over
           pretty quickly.
                       MEMBER WALLIS:  Maybe we need to discover
           what this extent -- the extent of this work with
           industry is.  I mean, they have their point of view,
           and you have your point of view.  They seem to be
           rather different.  Are you working together or --
                       MR. KURITZKY:  We are now having exchanges
           of information, but our first three options that we
           discussed in the beginning where we -- particularly
           Option 1 is very closely related to what industry is
                       MR. KING:  We've had a number of meetings
           with the industry as was mentioned, and I think what
           you heard Mike say was we're not closing the door on
           the path that they're pursuing.  What Mike's
           presentation tried to do was lay out the issues that
           we felt needed to be addressed if we're going to go
           down that path.  
                       It doesn't mean ultimately we won't go
           down that path, but it means between now and June not
           enough work has been done for us to go to the
           Commission and say, "Let's proceed down that path."
                       MEMBER WALLIS:  What they seem to be
           looking for, though, was for you to open the door and
           say, "We're going to encourage you to do more work
           because we think it's fruitful," rather than to hang
           a plaque on the door which discourages them from doing
           a lot more work.
                       MR. KING:  I think one of the things we
           have to talk about is, how wide is the door?  You
           know, how wide do they see it, and how wide do we see
                       MEMBER WALLIS:  We don't seem to agree yet
           on that.
                       MR. KING:  We probably don't agree on
           that, but I think from our perspective the door is
           open, and we've got to talk about is how wide is it
                       MEMBER WALLIS:  I'm not sure that at this
           stage the ACRS has enough evidence from both sides to
           give much advice about how open the door is.  If
           that's what we're being asked to do.
                       MEMBER BONACA:  One question I have is,
           have you given second thoughts about the generic
           implications of this step?  Really, this is the LOCA. 
           It was presented as the first DBA that can be changed
           where there is implications to load rejection.
                       It's equally unlikely, I think, as an
           event that you will have a sheer load rejection the
           way that you have in the FSAR.  It's true of the steam
           line break.
                       So if you make a change to the LOCA and
           then you go back into the risk evaluation and look at
           the comparisons between, you know, LOCA, you are
           reducing now the expectation resulting from the LOCA,
           but you are looking at the one imposed by the steam
           line break.  Well, tomorrow you will be changing the
           steam line break.  It will change further.
                       I think you have to look globally at here
           you are really fundamentally changing the way you're
           looking at your design of the plant, I mean, and
           you'll do it for a LOCA.  That's a point that also Dr.
           Kress has made, and, you know, without the
           implications for the other accidents.  I mean, it's --
                       MR. KURITZKY:  I think your point is very
           good.  Even if --
                       MEMBER BONACA:  I don't think you can wait
           until you have gone through this gate, and then decide
           how you're going to treat the other accident.  I think
           you have to think about and have some position on
           that, because it will have implications about, you
           know, anything that -- I mean, the example I made of
           doing your risk assessment based on the consequences
           of the LOCA and comparing it to other restrictions
           being imposed by the steam line break, and then coming
           in and having changes to the steam line break that
           will affect the changes you have made now with the
           LOCA.  I mean --
                       MR. KING:  What you are suggesting is
           let's take the whole set of DBAs, take a look at what
           risk information says about them.
                       MEMBER BONACA:  Yes.  I mean, if you're
           making --
                       MR. KING:  Make whatever changes you think
           make sense and then assess that.
                       MEMBER BONACA:  Or even if you progress
           aggressively just with the LOCA, I think you ought to
           have in mind some thoughts about how do you agree with
           the fact that this is a new approach that most likely
           is going to be applied with time to the other
           accidents in the way you design your plant.  I think
           you have to have an understanding; at least I think we
           have to have an understanding of how that will come
                       MR. KING:  I agree there are other things
           on the plate to be looked at, like the rod ejection
                       MEMBER BONACA:  Yes.  Steam line break,
           too, most likely.
                       MR. KING:  Steam line break, probably some
           others as well.
                       MEMBER BONACA:  Yes.
                       MR. KING:  And I agree you need to think
           about the implications of this for those other events,
           particularly if -- if those other events are
           preventing some of the -- the benefit or some of the
           improvements you're really expecting when you go to
           make this change, does it make sense to do that
           individually, or would you be better to go in and look
           at them as a group?
                       MEMBER BONACA:  Right.
                       MR. KING:  One of the things we need to
           spend more time on is looking at, if we would make
           such a change here, what are the other things that are
           going to catch you?  And how do we deal with those
           things, so that we take more of a collective or
           holistic look at this whole LOCA situation?
                       CHAIRMAN SHACK:  Of course, you know, one
           of the problems that Tom keeps pointing out, when you
           tackle the design basis approach here, you have a
           touch time evaluating the risk, because you don't --
           you're not really dealing with a specific change in a
                       You know, it's easier to estimate the
           change in CDF if the guy comes in and says, "I want to
           change my tech spec for diesel startup."  I can sit
           down and compute a delta CDF score.  Here you're going
           to change a design basis accident, and you really
           don't know exactly what he's going to do in response
           to that.
                       MR. KING:  Right.
                       CHAIRMAN SHACK:  So it becomes very
           difficult to go back and try to estimate the risk
           impact of this change because you don't know what the
           changes are, whereas if you're coming the other way
           it's a good deal easier.
                       MR. KING:  You have to think through, what
           are those changes that would ensue?  And what is the
           risk impact?  And maybe some licensees will implement
           them all and some won't.
                       CHAIRMAN SHACK:  But that's the fortune-
           telling aspect of this.
                       MR. KING:  Right.  But you've got to look
           at that.  I mean, there's no way around it.
                       MEMBER BONACA:  Although, I mean, for
           those changes which are being driven by LOCA -- for
           example, the diesel start times -- and you can
           determine that there are no other accidents driving
           that, okay, then you can, you know -- some assessment
           of it can be done.  
                       There are others which are more
           complicated because they are driven by other events,
           and so I agree with --
                       CHAIRMAN SHACK:  Yes.  But could you do a
           -- you know, a standard tech spec change for diesel
           start times?  You know, I mean, we -- I was just going
           to make a wise remark that, you know, it was a good
           thing you got the jet pipe whip restraints out there
           before we decided to risk-inform the regulations.
                       MR. MAYFIELD:  They'd still be there.
                       CHAIRMAN SHACK:  They'd still be there.
                       MR. MAYFIELD:  You were talk about the
           tentacles this thing has.  There was mention made this
           morning that one of the reliefs you'd get is some
           improvement.  Without making a change in containment
           design, you'd get some improvement in the calculated
           margin against failure.
                       If you had that improved calculated margin
           and then discovered that your containment was being
           degraded, and it was going to be a major deal to go
           get to it to repair it, would you then be inclined to
           use up that margin, or a part of it, to avoid a repair
           for a degraded containment?
                       I'm not going to speculate, but it seems
           to me that that's a question that if you were going to
           look at how the -- what changes might be made to a
           plant, you get captured in those kinds of things.  And
           it -- I think that's a very tough thing to do to -- to
           get out the crystal ball and guess at all the things
           people might do.
                       MEMBER KRESS:  It's crystal-balling,
           that's right, yes.  That's why it's hard.
                       MR. WARD:  That's one reason that we had
           -- are proposing an implementation guide with the
           large break LOCA redefinition, so that we go to you
           with a complete package of standard changes that had
           already been reviewed, so that if I get the rule
           change for my plant, then what we have already looked
           at on a generic basis for the diesel start times,
           accumulator number reduction, ECCS flow balancing, on
           and on and on, and have a complete package already
           reviewed and looked at as a compiled list, instead of
           trying to go at it like this, you know, piecemeal one
           at a time, and then figure out the impact, and then to
           piecemeal another one and figure out the impact of it.
                       There are other things, you know, that
           would go beyond that, of course, but if we -- if we
           try to piecemeal it one piece at a time like this, I
           don't think we'll get through it in my lifetime or
           most of our careers.  I think we will still be working
           on that list -- the near-term list, you know, when all
           of us are retired.
                       I think that's the reason we felt like we
           had to go all the way to the beginning and start from
           there and then work down and come up with a reasonable
           list of things to work on at the same time and not try
           to piecemeal this thing to death, because I think
           that's what will happen if we try to take that
                       MR. KURITZKY:  Okay.  In any case, so on
           the rest of these things, I think most of these items
           we've already discussed at various times.  Some of the
           things we're looking at in the longer term, maybe
           changing the ECCS acceptance criteria, the propagation
           of break size frequency, looking at ECCS availability
           for other modes of operation, and things like multiple
           steam generator tube rupture, you know, whether
           there's a need for multiple steam generator tube
           rupture DBA.
                       Going back to what we discussed before,
           even -- or maybe even in the short term looking at the
           need for maybe a different diesel generator DBA if
           we're going to relax that loss of offsite power
                       So these are some of the things that in
           the longer term we still -- we think we can come to
           some kind of grips on their feasibility.
                       MR. KING:  Okay.  The last viewgraph -- I
           mean, the purpose of the meeting today was to sort of
           put our cards on the table to show you where we stand. 
           We don't have all the answers.  We still have some
           work to do.  But at least we wanted to give you the
           opportunity here, from all the work that's been done
           so far, you know, where we've -- where we are today on
           some of these issues and how we see perceiving in the
           future both the near term and the long term.
                       Again, we're subject to scheduling.  You
           know, we'd like to have some future interactions with
           the committee leading up to our June paper.  That's
                       CHAIRMAN SHACK:  Just, you know, if you
           take the industry's suggestion with, you know, this --
           you're not defining -- you're not redefining the large
           break LOCA in the rule.  You're simply saying the
           large break LOCA can be redefined, and they will have
           to submit a package showing all the implications of
           that in terms of a risk argument.
                       Doesn't that still leave you in control
           and let you evaluate the things the way they -- rather
           than trying to crystal ball it --
                       MR. KING:  That's certainly one way to do
           it, just open the door for any plant to come in and
           say, "Here's my proposal.  These are the things I want
           to change."
                       CHAIRMAN SHACK:  But I'd have to do a
           fully risk-informed version of that.
                       MR. KING:  Risk study, fracture mechanics
           study, everything that comes along with it.  I think
           the question -- maybe Mike is better to answer this
           than me -- but are we in the position to lay out the
           Regulatory Guide that would have to be met, and the
           acceptance criteria that would have to be met?
                       There's a lot of things on Mike's list of
           things that should be addressed in such an analysis,
           and, you know, it's not clear to me that at this point
           we're ready to say, "This is the list, and this is how
           it ought to be approached."
                       MR. MAYFIELD:  I think that that really
           was the point I was trying to get to.  It's not that
           it can't be done.  It's that it's, we believe, a much
           more significant undertaking than has been suggested
           by some of the other discussions we've had.
                       As we've looked at what would -- what
           kinds of things would have to be addressed, it's a
           tougher analysis than has been suggested, where we
           don't believe what was done before for the leak before
           break rule change, in and of itself, was sufficient. 
           Is it a starting point?  Sure.  Of course.  
                       But it's a much tougher analysis to do. 
           The hurdle is higher than it has been for these other
           kinds of changes.  I mean, it's a tough job.  It's not
           that it can't be done, although I personally am
           skeptical that it's practical, but it's not that it
           can't be done.  But it's going to be a major resource
                       MEMBER BONACA:  You said that that was
           because for leak before break defense in depth was not
           challenged.  You said that it was covered by large
           break LOCA in 50.46 requirements.  So in case we
           really missed it, and you have a large break LOCA, you
           still have the ECCS capable of dealing with its own
           certain criteria.
                       MR. MAYFIELD:  Right.  
                       MEMBER BONACA:  Well, have you thought
           about the possibility of the criteria being -- I'm
           talking about, you know, there are a number of
           restrictions to the plant that you could relax based
           on a more likely break -- maximum break size.  And you
           could still impose some fundamental requirements, for
           example, coolability of the core, for, you know, that
           will end -- you can break.  
                       I'm just throwing out a thought because --
           because you still will have some results by the ECCS
           that will not deliver exactly for a full -- give you
           what you are supposed to, but it will, you know --
                       MR. KING:  You say relax the acceptance
           criteria for the large break, is that --
                       MEMBER BONACA:  I'm thinking about the
           fact that if you take out the DBA, not only the LOCA,
           and you reevaluate those with these new concepts in
           mind, you may think about the criteria as something
           with -- with expectations for the current DBAs to
           still be fulfilled, and probably systems are capable
           of delivering that.  And, you know, just --
                       MR. KING:  Yes.  I think I'm still not
           sure exactly what you're proposing.  Maybe we need
           some discussion.
                       MEMBER BONACA:  Well, once you relax your
           diesel starting time, and all of the other things we
           have seen here, okay, you still deliver a flow, and
           you will have some expectations for coolability of the
           core in case -- in case you have the truly double-
           ended guillotine break.
                       MR. KING:  I don't know.  Given the fact
           that the plants already have the right size pumps and
           pipes and everything in there --
                       MEMBER BONACA:  That's exactly right.
                       MR. KING:  For existing plants, that
           probably is --
                       MEMBER BONACA:  As was said this morning,
           that for new plants there will be a different kind
           of --
                       MR. KING:  Yes, new plants will be a
           different story.  
                       I may want to go back and mention one
           other fundamental assumption.  We're talking about,
           you know, we have a short-term and a long-term list. 
           One of our fundamental assumptions was, I mean, we
           could continue to work on the issues Mike has raised
           and do the -- do all of the analysis and develop the
           Reg. Guide and then have a complete package type
                       We're not ready to do that by June, but
           one of our fundamental assumptions was we thought it
           would be important to get some short-term successes
           under our belt on this issue and some short-term, you
           know, changes that would get rid of some of these
           unnecessary burdens and maybe -- maybe plug some
           safety enhancement holes.
                       That's why we're proposing to go forward
           in June with some -- some things that we think are
           reasonable, some things that will provide some
           advantages, some safety improvements, and continue to
           work on the long-term.  
                       I think if we decide not to do anything
           until all of the work is done, it's going to take some
           more time, and it's going to have negative
           implications for all of Option 3.  I think getting
           some successes under our belt is important, and that's
           one of the reasons we're proposing to have this two-
           tiered approach.  So, you know, I don't know what the
           committee's views on that are, or the industry's
           views, but that's our view.
                       MEMBER WALLIS:  Well, my impression, if
           you want a view, is that you have thought enough about
           these issues that you will probably come up with a
           good document in April, whenever this -- you know,
           April/May, that timeframe.  I mean, I've got a feeling
           that you know enough about it that --
                       MR. KING:  For the short-term things.
                       MEMBER WALLIS:  -- that you will come up
           with something by then, yes.
                       MR. KING:  Right.
                       MEMBER WALLIS:  So I'm sort of encouraged
           by the progress I've seen so far.
                       MEMBER KRESS:  I would like to throw out
           one of my favorite comments, and that is when you
           actually get around to doing this, the risk
           implications of the changes -- which may be way down
           the road on this thing -- I urge you to reconsider the
           guidance in 1.174 a little more, because the overall
           objectives of this agency are not just CDF and LERF.
                       They're releases of all magnitudes of
           fission products, including late failures and
           contamination, and even worker exposure.  So if those
           things are impacted and are going to change, you need
           to know it also.  And when you do the risk impact
           evaluation, don't just focus on CDF and LERF.  That's
           my plain issue.
                       MR. KING:  Okay.  We're finished with our
                       CHAIRMAN SHACK:  Okay.  I believe Mr.
           Heymer wanted to make some comments.
                       MR. HEYMER:  Adrian Heymer, NEI.  I've
           listened to the staff.  We've been discussing the
           issues with the staff for 15 months now.  I think what
           you've heard today is very much along the lines that
           the discussions have gone for the last 15 months. 
           We've looked into this.  We've evaluated it.  
                       The owners groups have got funding
           authorized to move forward on redefining the large
           break LOCA, and we believe that's where the priority
           should be.
                       So that's what we believe at the moment,
           and we are under no illusions that it's going to be a
           tough task.  But it's a tough task that's got, we
           believe, rewards commensurate with what they're going
           to have to expend to achieve our aim, in the order of
           probably quite substantial funding from the owners
           groups.  And by substantial I'm talking in the
           millions, not in the thousands.
                       I hear the staff talk about short term and
           near term, and I don't want to ask a question of the
           staff, but at some stage I would like a definition of
           what near term and short term is in their mind,
           because I've got a nasty feeling that what I think is
           near term is what they're thinking is something else. 
           So I'd be interested in hearing from the staff at that
           point in time.
                       We need to think about what's been said
           here today again and go back and discuss it amongst
           ourselves as an industry, and then see where we go
           from here.  So that's what I wanted to say.
                       MR. KING:  I mean, I think near term is
           propose some changes this June.  That's near term.  We
           want to be able to --
                       MR. HEYMER:  And do rulemaking by the end
           of the year?
                       MR. KING:  No, of course not.  You know,
           we go to the Commission in June and propose specific
           changes.  They say yes; the rulemaking starts.  Now,
           rulemaking doesn't take six months.  Generally, it
           takes two years.  Maybe 18 months if --
                       MR. HEYMER:  But, I mean, the -- it would
           be out by, say, six to nine months from the time the
           Commission said move ahead.
                       MR. KING:  Do you mean the proposed -- the
           notice of proposed rulemaking?
                       MR. HEYMER:  Yes.
                       MR. KING:  With the proposed rule?
                       MR. HEYMER:  Yes.
                       MR. KING:  That's probably a reasonable
                       CHAIRMAN SHACK:  Are there any more
           comments or questions from the committee members?  Any
           more questions or comments from the members of the
                       Okay.  Mike tells me our next subcommittee
           meeting on this subject will be May 8th.  Whether
           that's --
                       MEMBER WALLIS:  It will be a joint
           subcommittee like these three subcommittees together.
                       MEMBER APOSTOLAKIS:  Why was -- why
           May 8th for the May meeting?
                       MR. MARKLEY:  You decided at the last full
           committee meeting on that date.
                       MEMBER APOSTOLAKIS:  Well, that's a good
                       So May 8th is -- okay.
                       CHAIRMAN SHACK:  That basically means that
           the full committee can attend the meeting because it's
           sort of banged up against the full committee meeting,
           which is probably a good thing.
                       If there are no more questions or
           comments, then I think we can adjourn.
                                   (Whereupon, at 2:07 p.m., the proceedings
                       in the foregoing matter were adjourned.)


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