Thermal-Hydraulic Phenomena - October 25, 2001

                Official Transcript of Proceedings


Title:                    Advisory Committee on Reactor Safeguards
                               Thermal-Hydraulic Phenomena Subcommittee

Docket Number:  (not applicable)

Location:                 Rockville, Maryland

Date:                     Thursday, October 25, 2001

Work Order No.: NRC-082                               Pages 1-224

                   NEAL R. GROSS AND CO., INC.
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                             OCTOBER 25, 2001
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                            ROCKVILLE, MARYLAND
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                       The ACRS Thermal Phenomena Subcommittee 
           met at the Nuclear Regulatory Commission, Two White
           Flint North, Room T2B3, 11545 Rockville Pike, at 1:00
           p.m., Dr. Graham Wallis, Chairman,
                 DR. GRAHAM WALLIS, Chairman
                 DR. F. PETER FORD, Member
                 DR. THOMAS S. KRESS, Member
                 DR. WILLIAM SHACK, Member
                 DR. VIRGIL SCHROCK, ACRS Consultant
                 DR. JOHN D. SIEBER, Member
                      ACRS STAFF PRESENT:
                 PAUL A. BOEHNERT, ACRS Staff Engineer
                         AGENDA ITEM                       PAGE
           Introduction by Chairman Graham                    4
           Dresden/Quad Cities Power Uprates                  6
                                                    (1:00 p.m.)
                       CHAIRMAN WALLIS:  The meeting will now
           please come to order.  This is a meeting of the ACRS
           Subcommittee on Thermal-Hydraulic Phenomena.  I am
           Graham Wallis, Chairman of the Subcommittee.  
                       Other ACRS Members in attendance are Peter
           Ford, Thomas Kress, William Shack, and Jack Sieber. 
           The ACRS Consultant in attendance is Virgil Schrock. 
                       The purpose of this meeting is for the
           subcommittee to review the license amendment request
           of the Exelon Generating Company for core power
           uprates for the Dresden Nuclear Power Station, Units
           2 and 3; and the Quad Cities Nuclear Power Station,
           Units 1 and 2.
                       The subcommittee will gather information,
           and analyze relevant issues and facts, and formulate
           the proposed positions and actions as appropriate for
           deliberation by the full committee.  Mr. Paul Boehnert
           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 October 15, 2001.  
                       Portions of this meeting may be closed to
           the public as necessary to discuss information
           considered proprietary to General Electric Nuclear
                       A transcript of this meeting is being
           kept, and the open portions of this transcript will be
           made available as stated in the Federal Register
           notice.  It is requested that speakers first identify
           themselves, and speak with sufficient clarity and
           volume so that they can be readily heard. 
                       We have received no written comments or
           requests for time to make oral statements from members
           of the public.  I will say what I said before the last
           meeting that we had on power uprates, that this
           committee has received a large stack of papers, which
           amounted to over two feet high.
                       Some of my colleagues said that was an
           underestimate last time.  I am really looking forward
           to your help in pointing us to the elements of that
           which are important for us to consider.    So I will
           now proceed with the meeting, and I will call upon Mr.
           Bill Bohlke of the Exelon Generating Company after my
           colleague, Peter Ford, makes a statement.
                       DR. FORD:  Yes.  I am a GE retiree, and
           therefore I have a conflict of interest. 
                       MR. BOHLKE:  Thank you.  Good afternoon,
           Mr. Chairman, and Members of the ACRS.  I am Bill
           Bohlke, senior vice president of nuclear services for
           the Exelon Corporation, and the executive sponsor for
           the extended power uprate project for Dresden and Quad
                       We have brought many members of our
           project team who have been working on this project for
           almost two years now, and that this team of engineers,
           and analysts, and operators, I think is pretty well
           positioned to answer the question that you may have
           from reading the material and anything that comes up
           from their presentation, which we hope will help
           clarify and distill all of the information that you
           have been asked to digest.
                       This is an important project for our
           company.  As you are already aware, Dresden and Quad
           Cities are BWR-3s licensed for commercial operations
           from 1969 through 1972 or '73.  
                       Recently, we have seen significant
           improvements in the reliability and safe operation of
           those plants, and in addition to this extended power
           uprate request, we are preparing a license renewal
           application for Dresden and Quad which will be
           submitted at the end of next year.
                       So we have got a substantial investment
           going forward in these plants, and we are anxious to
           tell you how we plan to integrate this uprate into our
           operations, and why we believe that this uprate can be
           safely and reliably achieved.
                       We are also aware that you just went
           through similar material about a month ago on the
           Duane Arnold project.  There are many, many
           similarities between what you heard a month ago, and
           what you will hear today.
                       But there are also some differences,
           because these are BWR3s, and a little bit older than
           a Duane Arnold plant.  Nevertheless, let me summarize
           as I conclude what I think you are going to hear.  
                       That we have followed the GE designed
           approach for an extended power uprate described in
           their EPU license topical report for a constant
           pressure upgrade.  That is to say, the steam dome
           pressure doesn't change.
                       You will see that we have provided an
           extensive sweep of analyses using methodology that has
           been reviewed by the staff and you many times before
           to analyze these plants, and in several cases these
                       We represent an upgrade from the previous
           sweep of methodologies and analyses that existed for
           the units, and we have benefited from that, and we
           will also be able to demonstrate that the inputs to
           the analyses are accurate and reasonably conservative
           in addition.
                       The results of all of this work that we
           have gone through, and the modifications which are
           ensuing on Dresden 2 as we speak, because Dresden 2 is
           in the outage during which the modifications required
           for an extended power uprate must be implemented.  
                       And you will see that at the end of the
           day there are in fact no significant impacts on the
           way that the plant responds to initiating events or
           the way that the plant operates during transients. 
                       And there are no challenges to system
           integrity that are of any concern for us in an
           engineering context.  Near the end of the
           presentation, you will hear a rather extensive review
           of the risk assessment of this uprate.
                       And I think when you have seen what we
           have done and have heard the results, you will
           conclude as we have that there are minimal changes in
           plant risk.  
                       Thus, from all aspects, we believe that
           the plant operation following the increase in power to
           the extended level will be acceptable and safe.  At
           this time, pending any questions, I would like to turn
           it over to our project manager for this project, Mr.
           John Nosko.  Thank you.
                       MR. NOSKO:  Good afternoon.  My name is
           John Nosko, and I am the project manager for the
           Dresden and Quad Cities extended power uprate
                       Our presentation this afternoon has been
           constructed to generally follow the guidelines of the
           agenda provided by the subcommittee.  It incorporates
           materials to address the questions received from the
           ACRS before the meeting.
                       And we expect to take just over two hours,
           Mr. Chairman, to cover all of the topics, which allows
           time for questions from the subcommittee.  We have
           with us today members of our project team from Exelon,
           and from General Electric, Stone & Webster, and Aaron
           Engineering here, to support the presentation.
                       There is no proprietary information
           contained in our presentation, but it may turn out
           that responses to some of your questions would bring
           out proprietary information.  If that is the case, we
           will ask to address the matters separately with you,
           or in a closed session.
                       So looking at the agenda, we propose to
           cover our compliance with regulatory issues in the
           introduction and project overview.  We will talk about
           selected analyses and evaluations as requested by the
                       A separate presentation will focus on
           probablistic risk analyses, and including a discussion
           on open items identified in the draft safety
           evaluation report.
                       And finally we will talk about
           implementing the power uprates at the station from the
           perspective of an operating license holder.  Our
           submittal is requesting a 17 percent increase in
           license power level.
                       The goals of our project are to safely use
           the excess capacity currently available at the
           stations to increase power production levels to
           leverage industry experience using a proven and
           accepted methodology to minimize the impact of that
           uprate on the plant by maintaining a constant reactor
           dome pressure.
                       And to make our analyses and designs for
           both stations as similar as possible to simplify
           reviews and configuration management going forward. 
           Our submittal was prepared in accordance with the
           license topical reports for extended power uprates. 
           They are ELTRs 1 and 2.
                       And it demonstrates compliance with
           applicable regulations and safety limits.  The
           analyses that we have done consider a variety of
           operating transients, postulated accidents, and
           operating conditions.
                       We have evaluated the radiological
           consequences and environmental impacts of the uprate,
           as well as the effect of the uprate on station
                       Now, we have taken only one exception to
           the license topical reports, and that is for
           conducting major transient testing at uprated power
                       Our presentation will address why we are
           taking that exception, and why we believe there is
           compelling data to support that position.  The
           committee has also asked us to address the impact of
           the extended uprate on plant margins, and our approach
           this afternoon is to include that aspect in the
           presentation on the specific topics.
                       DR. SIEBER:  The large transient testing,
           this is two tests, right?
                       MR. NOSKO:  Yes, sir; MSIV closure, and
           generator load --
                       DR. SIEBER:  And maybe you could just say
           a sentence or so as to why you don't want to do that,
           because that is still an open item.
                       MR. NOSKO:  Yes, sir.  We have a -- if I
           could ask that the question be held until a later
           point in time.  We do have a separate session that
           deals with that directly.
                       DR. SIEBER:  All right.
                       MR. NOSKO:  Okay.  Thank you.  
                       DR. SCHROCK:  I have a question.  In
           reading these documents, I find that to a very great
           extent, and perhaps more than 95 percent, are verbatim
           for the two plants.  
                       And yet some numbers come out different
           here and there.  This is puzzling to me, and I don't
           understand the reasons for these differences.  I think
           a better starting point for me would be to tell us
           what are the plant specific differences that have to
           be dealt with.  
                       The scheme as I understand it is that you
           have the generic evaluation done in the G.E. reports,
           and that leaves plant specific considerations to be
           dealt with on a case by case basis.  
                       And what I don't find in these reports is
           a clear delineation of what the plant specific
           considerations are for each of these plants.  
                       MR. HAEGER:  I think that probably the
           best way to answer that is -- 
                       MR. BOEHNERT:  If you could introduce
                       MR. HAEGER:  Yes, I am Allan Haeger, and
           I work for Exelon in the licensing area.  We have in
           our presentation pointed out differences where we
           think that those are significant, and we are prepared
           to discuss the reasons for the differences at that
                       That might go to what you are asking.  If
           you would prefer to wait as we go through the
           presentation, there are opportunities there.  
                       DR. SCHROCK:  I am simply pointing out
           that I have difficulty digesting the material and
           making sense of it for this reason and a few others,
           but it would be helpful I think if you could tell us
           what he plant specific considerations are.  That does
           not seem like an onerous request I don't believe.
                       MR. NOSKO:  Well, they are sister
           stations, and they are both BWR-3s.  The Dresden
           station uses an isolation condenser, for example;
           whereas, Quad Cities is a little bit behind Dresden,
           uses a RCIC system, reactor core isolation cooling
                       There are differences in safe shutdown. 
           They have a safe shutdown pump at the Quad Cities
           station, and a separate system to address that for
           fire protection areas.  We don't have that in the
           Dresden station.
                       It is things like that.  But I am sure
           that we will be able to clarify this in the
           presentation, and if we fail, please bring that to our
           attention, and we will make sure that we get that
                       DR. SIEBER:  In your list of things that
           you are going to talk about, some of the questions
           that I sent in had to do with the fuel design, and I
           recognized that the lead safety analysis are separate
           from the upgrade.
                       But I would be interested in knowing a
           little bit more about the details of the fuel design
           than currently appears in the SER.  Can you address
           that or do you plan to address that?
                       MR. NOSKO:  Well, since the application
           for G.E. 14 fuel was a separate licensing submittal,
           we were not intending to address any of the specifics
           about the G.E. 14 fuel.  
                       But depending on the questions, and
           depending on the proprietary nature, we might be able
                       MR. HAEGER:  We certainly have personnel
           here who can speak and answer those questions.
                       DR. SIEBER:  Well, it seems to me that
           when you extend the rating of the plant by 17 percent,
           other than a few balance of plant things and some new
           analysis that you have to do, everything depends on
           the fuel, and that is where you are getting the uprate
                       MR. HAEGER:  That's right.
                       DR. SIEBER:  And so to me I think it is
           part-and-parcel of it.
                       MR. HAEGER:  Well, we will be covering the
           fuel's response to at risk to LOCA, and we talk about
           the general design to some degree.  But I think there
           is enough points in the presentation that touch on
           that that is an appropriate place to answer questions.
                       DR. SIEBER:  The ACRS doesn't get the
           opportunity to review safety reload, safety
           evaluations, and so we may miss out on the full
           understanding of just exactly what the uprate is all
           about, and how you achieve it, and everything that is
                       Because you actually affect a lot of
           things when you change the fuel parameters.  It
           changes the results and the results virtually of all 
           the safety analyses as I see it.  
                       Well, let's see what you do, and to the
           extent that you miss the questions that I submitted,
           then I will ask them at the appropriate time.
                       MR. NOSKO:  Okay.  This next slide is a
           power-to-flow map, and you are very familiar with
           this.  We have a chart over there that is not as
           visible as we had hoped that it would be and our
                       From this chart, you can identify the
           current hundred percent power level, and the power
           level for uprated conditions, the 2957, and that is
           the far upper right.
                       DR. FORD:  Can I ask about this chart?  I
           mean, this chart -- well, what does it depend on?  It
           depends upon what?
                       MR. NOSKO:  Core flow.
                       DR. FORD:  It depends upon the fuel
           design, and the way the flux is flattened, and so on? 
           Or is it something much more basic than that?  Does
           this middle upper boundary move around as you change
           the way in which you fuel the reactor, or design your
           flux distribution and so on?
                       MR. NOSKO:  Jens or Jason, would you help
           us with that.
                       MR. POST:  Yes, this is Jason Post of G.E. 
           The MELLLA upper boundary is a licensed limit, and
           that does not change.  That is fixed in space, and
           that does not change from reload to reload.  
                       There can be small variations in the load
           lines as a result of the core design, but the changes
           are pretty small, and we have equations that we use
           when we define those, and they basically don't change
           significantly from cycle to cycle.
                       DR. FORD:  Thank you.
                       DR. SCHROCK:  I saw those equations and
           they look like empirical relations.  They don't seem
           to relate to any physical aspect of the plant.  I
           think that I would like to ask the question that
           Graham just asked again.  What is the basis of the
           line?  How does it come to be where it is as a
           licensing limit?
                       MR. PAPPONE:  This is Dan Pappone of G.E. 
           The rod lines that are shown on the power flow map did
           have their origination back in the plant design plant
           response, but we have fixed those in licensing space.
                       So they approximate what the actual
           response would be, but we are treating these as
           licensing boundaries.  So that helps.
                       MR. NOSKO:  So you are right; they are
                       MR. POST:  It is an empirical bounding fit
           to an original set of calculations, and having done
           that original fit, we are now drawing that line and
           saying this is our licensing boundary, and we will not
           allow a plant operation outside of that boundary.
                       DR. SCHROCK:  But if I am not mistaken,
           that is one of the unexplained differences between
           Quad Cities and the Dresden plants.  These power flow
           maps are not identical, and they differ significantly
           I think.  Is that right?
                       MR. PAPPONE:  I believe that we kept the
           power flow maps the same, or what we are counting as
           a licensed power flow map, and I believe that is the
                       MR. NOSKO:  For the uprate, yes.  That's
                       MR. PAPPONE:  For the uprate, yes.
                       MR. NOSKO:  Today they have differences in
           their licensed power levels.  Dresden is 27 (sic)
           megawatts thermal for their license level; and Quad
           Cities is 2511.  So there are some differences there.
                       DR. SCHROCK:  And that is an affirmed
                       MR. NOSKO:  Correct.  And when we go to
           the uprate power, we are bringing those two together
           as part of maintaining a common configuration
                       DR. SCHROCK:  Well, I will have to look
           again, but in searching for what are the differences
           between these two reports, two sets of reports, I was
           struck by the fact that here were different numbers,
           different positioning of various lines -- this little
           dashed line, which has something to do with natural
           circulation, was in a different place.
                       But the numbers in the table that
           characterize where the lines are seem to be different
           also in Quad Cities and in the Dresden reports, SERs. 
           So we will have to look again to confirm if I am right
           or am I wrong.
                       MR. HAEGER:  What we will do is we will
           look closely at those, and try to explain any minor
           differences, and I think they are probably minor, but
           any differences in those.
                       MR. NOSKO:  Okay.  And the purpose of this
           slide frankly was to demonstrate that MELLLA allows us
           to operate at higher power levels without changing
           core flows.
                       The next slide summarizes differences in
           key operating parameters between plants today and what
           we expect after the uprate in Dresden.
                       CHAIRMAN WALLIS:  And you talked about
           flow rate just now.  The flow rates on this diagram
           are not the same as they are either for Quad Cities or
           for Dresden on page 115 on the G.E. safety analysis
                       And I don't know what the differences are
           due to, and Quad Cities shows 105.8 for its full power
           core flow range maximum; and Dresden shows 98.  I
           don't know why they are different, and yet Dresden
           shows 105.8 for its extended power uprate, which is
           not on yours either.  And these are different numbers,
           and I just don't understand why they are so different.
                       MR. HAEGER:  I think I can handle that. 
           The full power expected core flow for both stations is
           going to be as shown here, 98 million pounds mass per
                       Now, Quad Cities currently is licensed to
           achieve what they call increased core flow, which is
           to go beyond the right boundary of the power flow map
           into that increased core flow region.  Dresden is not.
                       For the power uprate, we did some of the
           analysis, and it was stated that we did some of the
           analysis for Dresden at that increased core flow range
           to support future potential licensing actions.  But
           the full power, 100 percent core flow for both
           stations will be the same at 98.  
                       CHAIRMAN WALLIS:  This is one of the
           things that is confusing when you see different
           numbers in different places for the same thing, and it
           needs some explanation.
                       MR. HAEGER:  Well, we do analysis -- and
           you are going to see a few more differences.
                       CHAIRMAN WALLIS:  So it is true then is it
           that you are not extending the core flow rate with
           this application, but that you would like to do so
           sometime in the future, which is why you have some
           higher numbers in some of these other places?
                       MR. HAEGER:  That's correct.
                       CHAIRMAN WALLIS:  Thank you.
                       MR. NOSKO:  Quickly summarizing some of
           these high points, the Dresden station, I mentioned
           thermal power is increasing from 2527 to 2957
           megawatts thermal, and Quad Cities is going from their
           current 2511 to their same uprated level.  
                       Steam flow is increasing from about 9.8
           million pounds per hour to just over 11.7 million
           pounds per hour.  And as you saw in the power flow
           map, the range of core flow at full power decreases
           somewhat under uprated conditions, but maximum flow
           through the core is not changing.
                       And you can also see here that we are not
           changing dome pressure or --
                       CHAIRMAN WALLIS:  The core flow rate has
           to have a range because of condenser temperature
           variations or something to get the same power; is that
           why it varies?
                       MR. NOSKO:  The range on the -- you are
           talking about full power?
                       CHAIRMAN WALLIS:  Why is there a range? 
           Why isn't it just 98?  Why is it 85 to 98?
                       MR. NOSKO:  It is a function of the MELLLA
           line, where the MELLLA line intersects full power.
                       CHAIRMAN WALLIS:  Oh, it is the flat part.
                       MR. NOSKO:  Yes.  Moving on, this uprate
           will be accomplished in one phase.  Mr. Bohlke
           mentioned earlier in his presentation that plant
           modifications will be installed during the next
           refueling outage for each unit, and in the on-line
           period immediately preceding that refueling outage.
                       I mentioned earlier that we will be taking
           advantage of installed spare capacity at the stations. 
           These spares are maintenance spares for the plant, and
           the most obvious example that we have is that we will
           be operating all four of our condensate booster pumps,
           and all three of our motor driven reactor feed pumps.
                       But I should say also that the use of all
           installed feed and condensate pumps is common in the
           industry, and it is just a difference for Exelon at
           this time.  
                       Following the uprate, our units will be
           generator limited, which means that we will be varying
           reactor power seasonally to account for temperature
           differences so that we maintain maximum output from
           the generators.
                       And this slide also shows our schedule for
           implementing the uprates at the four units.  Dresden-2
           is in its outage now, and the remaining three units
           will undergo their outages for the uprate next year.
                       Turning now to the modifications that we
           will be making to the station.  You will find that the
           power uprate generally requires the same modifications
           to be made at both stations.  There are relatively few
           safety related modifications, and the majority of the
           changes are being made to the balance of plant
                       CHAIRMAN WALLIS:  I am going to ask you a
           question, because I don't see it in your presentation
           here.  The method for increasing the power without
           raising the flow rates through core and the pressure
           and so on is flux flattening essentially.
                       So what we have seen is that you have a
           higher flux than you would have had before at the
           outside of the assemblies of the core.  And yet I
           understand that the fluence, the vessel fluence, goes
           down with a power uprate.  How do you achieve that?
                       MR. NOSKO:  Well, we are prepared to
           discuss that.
                       CHAIRMAN WALLIS:  Well, I didn't see it in
           your presentation.
                       MR. NOSKO:  It is there.
                       CHAIRMAN WALLIS:  It is there?  Okay.
                       MR. HAEGER:  It is slightly touched.
                       CHAIRMAN WALLIS:  So you are going to
           answer that question later then? 
                       MR. HAEGER:  Yes, sir.
                       CHAIRMAN WALLIS:  Thank you.
                       MR. NOSKO:  I would like to talk about the
           more significant plant changes that we will be making
           for the uprate, using the chart behind Mr. Haeger as
           a rough guide.
                       That chart over there is a very simplified
           schematic of the steam and feed water cycles.  I will
           begin in the upper left-hand corner with the changes
           to the reactor internals, and then follow that diagram
           in a clockwise manner through the turbine, the
           condenser, through the feed water system, and then
           back to the reactor.
                       So starting with the reactor.  New G.E. 14
           fuel assemblies will replace existing G.E. and
           Siemens's fuel.  This will be done gradually over 3 to
           4 operating cycles, and this new fuel type will allow
           us to reach the higher EPU power levels, while
           maintaining a 24 month operating cycle.
                       Mr. Bohlke mentioned that Dresden and Quad
           Cities are BWR-3 units.  As such the steam dryers are
           smaller than those of the later designed BWR-4s, 5s,
           and 6s, and they are not able to handle the increased
           steam flow of an extended power uprate as well.
                       So to prevent the higher moisture
           carryover levels predicted for the uprate, we elected
           to modify the steam dryers to keep those levels to no
           greater than what they are today.  
                       We are adding clamps to 8 of the 20 jet
           pump sensing lines to eliminate a concern for
           potential vibration induced failure of those lines
           caused by the vein passing frequency of the
           recirculation pumps.  
                       A reactor recirculation system runback and
           the low SCRAM level set point change are being added
           to improve station availability.  Today, only two of
           the three feed pumps and 3 of the 4 condensate pumps
           operate at rated power.  
                       If one pump trips, the standby pump
           automatically starts.  After the uprate, we won't have
           a standby pump, and so we are adding a run back
           feature and a SCRAM set point change to prevent low
           water level SCRAM on either a loss of a single feed
           pump or a single condensate pump.
                       Changes to the isolation condenser time
           delay relay at Dresden and to the low pressure coolant
           injection swing bus timer at both times are being made
           to reflect new accident analyses for the extended
           power uprate.  And we are also making some changes to
           set points on nuclear instrumentation.
                       DR. SIEBER:  Before you leave that, what
           is your guaranteed maximum moisture content at the
           reactor outlet right now?  Is it one percent? 
                       MR. NOSKO:  Currently today?
                       DR. SIEBER:  Yes.
                       MR. HAEGER:  The acceptance test for the
           original steam dryers was less than .2 percent.
                       DR. SIEBER:  So, .2?
                       MR. HAEGER:  Yes.
                       DR. SIEBER:  And what modifications are
           you making to the dryers?
                       MR. HAEGER:  We have a couple of slides on
           that later in the presentation that show an insertion
           of a perforated plate.
                       DR. SIEBER:  Is that going to change the
           pressure drop?
                       MR. HAEGER:  That is going to change the
           pressure drop.
                       DR. SIEBER:  Do you know by how much?
                       CHAIRMAN WALLIS:  Well, the higher flow
           rate will change the pressure drop, too, right?
                       MR. NOSKO:  Right.
                       CHAIRMAN WALLIS:  So you actually have a
           lower pressure at your turbine than you would like or
           that you have now?  
                       MR. NOSKO:  Than we have now, yes.  I
           don't have that specific piece of data, but I am sure
           that we will collect it.
                       DR. SIEBER:  Right.
                       MR. NOSKO:  Okay.  So moving on to the
           turbine generator system modifications, we are making
           changes to our high pressure steam path by installing
           new high pressure turbines, and we are also changing
           the cross-around relief valve set points.
                       An additional steam line residence
           compensator card is being installed in our electro
           hydraulic control circuitry to handle the third level
           harmonic for the steam piping system.  
                       And at Dresden, we found that the existing
           isolated phase bus up cooling system was not
           adequately sized to handle the uprate, and so we are
           making a change to improve the cooling capacity of
           that system.  
                       DR. SIEBER:  You are putting in a new
           return line?
                       MR. HAEGER:  Yes, we are.  We are putting
           in a new return line, and we are having all the
           cooling go down all three of the phases.
                       DR. SIEBER:  And you aren't doing anything
           to the generator to improve cooling I take it or are
                       MR. HAEGER:  We are increasing the flow of
           standard water cooling to the generator, but it is a
           small issue.  I didn't include it int his
                       DR. SIEBER:  And how are you doing that? 
           You aren't changing anything.  Does that take cooling
           water away from other components in the plant and make
           that system marginal?  Is that just a turbine plant
           closed cooling water system?
                       MR. HAEGER:   Yes, and that has been
                       DR. SIEBER:  And you have enough capacity?
                       MR. HAEGER:  Actually, standard water
           cooling is service water.
                       DR. SIEBER:  Service water?
                       MR. HAEGER:  Yes.
                       DR. SIEBER:  Well, that is still a closed
           cooling system, and you can't put service water there.
                       MR. NOSKO:  You are correct.  Standard
           cooling is the closest one. And I didn't mention, but
           Quad Cities doesn't have this problem.  This is a
           Dresden-unique situation.
                       Continuing now with changes to the
           condensate and feed water systems.  The increased flow
           from the uprate causes additional stresses on the
           condenser tubes, particularly in cold weather.
                       Several years ago, the Quad Cities station
           installed intermediate bracing for their condenser
           tubes to eliminate a concern that they had over tube
           vibration.  Dresden did not at that time.  So now we
           are making that change at the Dresden station as a
           part of this uprate.
                       DR. SIEBER:  Have you noticed damage at
           the current levels to condenser tubes on expanded
                       MR. NOSKO:  No, sir, not at the Dresden
           station, and Quad Cities, after they went through
                       DR. SIEBER:  And what kind of tubes are
           they?  Do you know?  
                       MR. NOSKO:  They are stainless.
                       DR. SIEBER:  Stainless?  Okay.  But you
           are expecting that the potential for vibration due to
           the increased exhaust flow will cause damage?
                       MR. NOSKO:  Well, we are expecting that if
           it is staked at the present station, and the stakes
           that we have at Quad have been evaluated for the
           increased steam flow and they are adequate.
                       DR. SIEBER:  Right.  That is a time
           consuming modification to put all of those things in
           there, and there are tons of them.
                       MR. NOSKO:  Yes.  The increased condensate
           and feed water flow also requires us to increase the
           capacities of the condensate demineralizer systems at
           both stations.  Dresden and Quad Cities use four
           stages of feed water heating. 
                       The uprate increases extraction steam flow
           from the low pressure turbines to the feed water
           heaters, and this raises the internal pressure of the
                       For our two lowest pressure feed water
           heaters, that pressure increase is small enough so
           that the heaters will continue to operate within their
           existing design rating.
                       This is not the case for our two highest
           pressure heaters, and so we are making modifications
           to allow us to increase the pressure ratings of those
                       We are increasing the capacity of the
           bravo heater and normal drain valves at the Dresden
           station to maintain heater normal water level control,
           and avoid the need to bias open our emergency spills. 
                       Because of similar changes already made at
           the Quad Cities station that modification isn't needed
           there.  A change that is being made at the Quad Cities
           station, but not at Dresden, is the staggered feed
           pump low suction pressure trips.  
                       Right now at Quad Cities all the reactor
           feed pumps trip on a low suction pressure signal, and
           after the uprate, they will be staggered somewhat,
           depending on the duration of that low pressure signal.
                       And separately from the extended power
           uprate project, a new digital feed water control
           system is being installed at the Quad Cities station. 
           It of course will be tested and adjusted to support
           planned uprated conditions.
                       And then there are plant changes that
           don't neatly fit into any of the previous categories. 
           The results of the piping analyses require us to make
           some changes to our main steam and torus-attached
           piping supports, as well as to some drywell support
                       We are upgrading the interrupting
           capability of the non-safety related 4kV switchgear to
           handle the additional running loads.  A feature to
           trip the delta condensate pump in the event of a loss
           of coolant accident is being added to retain the
           ability to make up with feed water.
                       And the Dresden station uses a cooling
           lake and supplemental cooling towers to cool the
           circulating water.  We have plans to install new
           cooling towers at the Dresden station to install, or
           excuse me, to handle the additional heat load from the
                       But this is an economic decision driven
           primarily to avoid derating the plants in the summer
           months.  Depending on the results of more recent
           economic evaluations, we may elect to defer
           installation of those additional cooling towers to a
           later date.
                       While we are prepared to go on to selected
           analyses and evaluations, I thought I would ask the
           committee if there are no further questions on the
                       DR. SIEBER:  I have a couple of questions. 
           Because you are now operating your installed spares as
           to provide sufficient pumping capacity, that creates
           a problem with your unit auxiliary transformer and its
           spare; where when you get a bus transfer, you end up
           with more load on the spare transformer than it is
           rated for.
                       And you have addressed that in a number of
           ways, one of which was to test the circuit breaker for
           interrupting capability.  I presume that test is
           complete and satisfactory?
                       MR. NOSKO:  Yes.
                       DR. SIEBER:  And another thing that you
           did was to cut out the instantaneous over current
           protection so that you would end up with a six cycle
           delay or something like that?  
                       MR. NOSKO:  Yes.
                       DR. SIEBER:  What was the basis of doing
           that?  Was it because the peak was too high?
                       MR. HAEGER:  I believe that is the case,
                       MR. NOSKO:  Right now I am not sure
           whether it is the interrupting or the instantaneous.
                       DR. SIEBER:  It is the instantaneous that
           was cut out, and the long term one is designed to
           allow you to start motors where the current one would
           go above the operating current, and as the motor
           starts to the normal operating current.
                       The instantaneous one is for short-circuit
           protection, which now if you have a bolt short in your
           system, you have no protection.  So when you close on
           it --
                       MR. HAEGER:  As I understand it, the
           equivalent protection is obtained by the other relay
           scheme in there that is maintained, but I am not an
           electrical expert.  Is there anybody back there that
           can help with this?
                       MR. KLUGE:  Yes, I am Mark Kluge from
           Exelon.  The test that was performed actually used the
           short-circuit current and then with some modifications
           to the switch gear bracing, and the switch gear then
           proved capable of interrupting that, even with the six
           cycle delay.
                       DR. SIEBER:  The question is not whether
           the circuit-breaker can interrupt it, but whether the
           transformer can take that fault, because the
           protection is gone. 
                       MR. HAEGER:  Yes, and I am pretty sure
           that the answer lies in the equivalent protections in
           the other features of the release scheme.  Let us
           confirm that for you.  
                       DR. SIEBER:  Okay.  Now, the other part of
           that is that you end up with a required manual
           operator action to eliminate or disable some of the
           loads on that transformer to bring it back to its
           current rating.
                       And I take it that the effect of the
           operator not doing some stripping on those buses would
           lead to damage to the core or to the windings of the
           transformer and cause overheating.
                       And you say if he does it within an hour
           everything is just perfect, and where did the one hour
           come from?
                       MR. NOSKO:  We had a separate evaluation
                       DR. SIEBER:  Yes, I have read that, and
           they said one hour, and the question is how did they
           come up with that?  What was the basis?
                       MR. NOSKO:   The basis?  I need to --
                       DR. SIEBER:  Or is that engineering
                       MR. NOSKO:  No, sir, it was based on the
           test results.
                       DR. SIEBER:  Well, it takes the life out
           of the transformer when you do that.
                       MR. HAEGER:  That's correct.  We
           understand that to be the case, but as far as the
           specific basis, I think we are going to have to get
           back to you on that.
                       CHAIRMAN WALLIS:  One hour sounds like a
           rounded-off number in some way.
                       DR. SIEBER:  It certainly does.  It should
           have been 58 minutes, and then we would believe it and
           not ask the question.
                       MR. HANLEY:  This is Tim Hanley from
           Exelon.  I believe the one hour actually came from me. 
           I am the operations representative and I had  them
           evaluate it at one hour because I thought that was an
           acceptable time period for which the operators to take
           those actions.
                       So it was a backward calculation on would
           it be okay from an hour.  So I believe that is why it
           is such a round number.
                       DR. SIEBER:  Let me ask since you are the
           operating person, you probably know this.  Does Exelon
           or its predecessor have a practice of looking at
           transformer gas composition?
                       MR. HANLEY:  Absolutely.  
                       DR. SIEBER:  How often do you do it on
           that transformer; do you know?
                       MR. HANLEY:  We take oil samples to
           measure the gas content I believe on a monthly basis
           on all of our large power transformers.  So, in an
           event like this, if we knew that we had over duty on
           the transformer for some period of time, we would
           immediately go out and take another sample and check
           for gasing.  
                       But we do have an analysis program that we
           do on a regular basis for all the large power
           transformers at the plant.
                       DR. SIEBER:  And if somebody from your
           laboratory came back and said you have got high
           acetylene in this transformer, what would you do as an
                       MR. HANLEY:  It depends on the level at
           which it comes back at.  We trend that.  In fact,
           Dresden this past summer had a transformer that was
           gasing and they trended it over time, and did a
           control plant shutdown, and shut down, and went in and
           repaired the transformer and brought the unit back on-
                       DR. SIEBER:  Why would it be a shutdown?
                       MR. HANLEY:  You would have to with the
           unidox transformer, because it is tied directly to the
           generator.  There is no way to separate it without
           taking the unit off-line.
                       DR. SIEBER:  Thank you.
                       MR. NOSKO:  Moving then to the selected
           analyses and evaluations.  A full scope of the
           evaluations was performed in accordance with the
           ELTRs.  These analyses were used to prove methods
           within previously accepted ranges and in all cases the
           results were within the acceptance criteria for the
           planned EPU configuration.
                       This next slide identifies the analyses
           and evaluations that we will be covering; the
           containment, the emergency core cooling system; and
           thermal-hydraulic stability.  We will talk about the
           anticipated transient without SCRAM analogies, piping,
           and also we will look at the effects of the power
           uprate on reactor internals, and the flow accelerated
           corrosion programs at the stations.
                       These were selected for discussion based
           on a request from the committee and in the case of the
           reactor internals, because of recent industry
           operating experience.  And with that, I will turn the
           discussion over to Mark Kluge, who will begin with the
           review of the containment analyses.
                       DR. SCHROCK:  Excuse me, but before you
           leave, could you say what the current licensing basis
           for these plants is?
                       MR. NOSKO:  In terms of what, sir?
                       MR. HAEGER:  Yes, can you be more
                       CHAIRMAN WALLIS:  That's a pretty broad
                       DR. SCHROCK:  Right.  Well, in terms of
           the LOCA evaluation is what I am thinking of.
                       MR. NOSKO:  Those are covered in this
           presentation.  They are summarized along with the pre-
           EPU and the post.
                       MR. HAEGER:  Are you asking for the
           methodology or the --
                       DR. SCHROCK:  Well, I will ask the
           question subsequently.
                       MR. NOSKO:  Okay.  Very good.  Thank you.
                       MR. KLUGE:  Good afternoon.  I am Mark
           Kluge from Exelon's EPU project engineering team, and
           I will be discussing the containment analysis that we
           performed for the Dresden and Quad Cities power
                       I will cover the methodology that we used
           to perform these analyses, and we will look at the
           results for the design basis accident, and we will
           also look at the Mark I hydrodynamic loads, and I will
           summarize the conclusions of the containment
                       CHAIRMAN WALLIS:  When you say design,
           there are several design basis accidents.
                       MR. KLUGE:  The design basis accident that
           I am referring to is the maximum recirculation and
           suction line break.
                       CHAIRMAN WALLIS:  The most critical one or
           something like that?
                       MR. KLUGE:  It provides the limiting case
           for containment and--
                       CHAIRMAN WALLIS:  Okay.
                       MR. KLUGE:  A containment analysis is
           performed in two phases; a short-term phase, and a
           long-term phase.  For the short-term analysis, we use
           the M3CPT and LAMB codes.  LAMB models flow down and
           then M3CPT calculates the peak dry well pressure and
                       In the long term, we use the SHEX code,
           which then looks at the conditions in the suppression
           pool.  And for the Mark I hydrodynamic loads, we use
           the methodologies that were defined during the Mark I
           long-term program.
                       In all cases our EPU license power is
           within the range for which these codes are applicable,
           and we analyzed a full spectrum of break sizes and
           locations, and we used conservative input parameters
           so that we would have conservative results.
                       Moving to the next slide, the results for
           the design basis accident.  Peak drywell pressure, you
           can see that when we perform the calculation with the
           same methodology for current conditions and uprate
           conditions, here is approximately a one pound rise in
           peak containment pressure, which is still well below
           the acceptance limit for these containments.
                       For drywell air temperature, again when we
           perform the pre-EPU and the EPU case, we have a very
           nominal two degree rise in peak drywell air
                       CHAIRMAN WALLIS:  Now, the drywell metal
                       MR. KLUGE:  The drywell metal is designed
           for a temperature of 281 degrees.
                       CHAIRMAN WALLIS:  And you have to do some
           transient heat transfer analyses or something?
                       MR. KLUGE:  That's correct, and in this
           case the design basis loss of coolant accident is not
           even limiting for the drywell metal temperature.  The
           peak temperature that is given here, and the air
           temperature lasts less than 10 seconds and simply is
           not there long enough to eat up the drywell shell to
           its limit.
                       CHAIRMAN WALLIS:  I read that, and I would
           be a little reassured if you had actually given a
           number to how hot it gets.  How hot does it get in
           this 10 seconds?
                       MR. KLUGE:  I believe the peak drywell
           temperature is in the 277 degree range.
                       CHAIRMAN WALLIS:  So it is a few degrees
           off the limit.
                       MR. PAPPONE:  This is Dan Pappone.  That
           is a typical result that we have seen for
           recirculation line break analysis, and 5 to 10 degrees
           below the shell temperature has been 5 to 10 degrees
           below the design temperature.
                       MR. KLUGE:  Going on to the next slide,
           here are the results for the suppression coolant --
                       CHAIRMAN WALLIS:  Typically is it always
                       MR. KLUGE:  Well, the reason that I said
           typically is that last month we did have the shell
           temperature slightly above, but when they went and
           looked at the structural evaluation for that higher
           temperature in the case where it did come up higher on
           the shell temperature, the structural analysis was
           still acceptable.
                       And so occasionally we have seen the
           drywell shell come above the 281 limit by a handful of
           degrees, and if we go to the next step in the
           structural analysis.  The structural analysis results
           were okay. 
                       DR. SIEBER:  So when you say last month,
           Dan, you were talking about?
                       MR. PAPPONE:  The Duane Arnold analysis.
                       CHAIRMAN WALLIS:  The calculation and not
           an event.  So what is the regulation?  The regulation
           says that if it is above 281, then you have to do a
           detailed structural analysis or something?  What does
           the regulation say about this structural limit?
                       MR. HAEGER:  I don't believe there is any
           direct regulation on this.  I believe that the
           licensing process is to set the structural limit, and
           then ensure that you don't achieve it; or if you do,
           justify a new structural limit.
                       MR. PAPPONE:  This is Dan Pappone.  The
           containment for the drywell torus shells are ASME
           pressure vessels, and so at that point we are working
           within the ASME structural codes.  
                       CHAIRMAN WALLIS:  So there is nothing
           written in some CFR document which says that 281 is a
                       MR. PAPPONE:  No.  
                       CHAIRMAN WALLIS:  I guess we can ask the
           staff the same question and what they think about
           these when we get to them tomorrow.
                       MR. KLUGE:  Moving on to the suppression
           pool analysis.  When we did a limiting analysis using
           the most conservative inputs from the two sites, we
           saw that EPU resulted in approximately a 9 degree rise
           in suppression pool peak temperature.
                       We used that bounding analysis, 202
           degrees, in the containment analysis and piping
           analysis.  We also calculated plant specific heat
           suppression pool temperatures, and that was used in
           the ECCS and NPSH analysis, and as you can see those
           numbers are lower than the limiting analysis.
                       For the EPU wetwell pressure analysis,
           again we had a very nominal rise in peak wetwell
           pressure when we applied the same methodology to the
           pre-EPU and post-EPU case.  
                       The Mark-I hydrodynamic loads, we looked
           at pool swell, and vent thrust, condensation
           oscillation, chugging, and SRV discharge loads.  We
           ran all the limiting cases for EPU as John Nosko
           mentioned, and reactor pressure does not change for
           this uprate.  
                       That is a primary driver in these
           hydrodynamic loads.  So we found in all cases the
           current Mark-I load definitions remained bounding for
           these plants.
                       DR. SIEBER:  That is for pressure and
           flow, as opposed to duration of the transient, right? 
           Because there is additional energy in the extended --
                       MR. KLUGE:  There is additional energy,
           but it was all within the original load definitions.
                       DR. SIEBER:  Okay.  Do you use some kind
           of a starter or something like that on your safety and
           relief help discharge lines?
                       MR. KLUGE:  We have T-quenchers.  In
           conclusion, the containment analyses we performed for
           EPU used accepted methods within the range for which
           those codes are applicable.  
                       We chose conservative input parameters and
           all of our results were within acceptance criteria. 
           Therefore, we conclude that containment performance is
           acceptable under EPU conditions.  
                       If there are no questions, I would like to
           introduce John Freeman, of our nuclear fuels
           department, to talk about the ECCS-LOCA analysis.
                       CHAIRMAN WALLIS:  Well, can we conclude
           that not only containment performance acceptable, but
           containment performance is not a feature which limits
           the amount of power uprate that you can have within
           the range you are considering.
                       And that you are not getting close to a
           limit in containment performance which is preventing
           you from going to, say, 3,000 megawatts?
                       MR. KLUGE:  That is correct.  As you
           observed, there is substantial margins in all of the
           containment acceptance criteria.
                       CHAIRMAN WALLIS:  Thank you.
                       MR. FREEMAN:  Good afternoon.  My name is
           John Freeman, with Exelon Nuclear Fuel Management.  I
           am going to discuss emergency core cooling analysis,
           along with Dan Pappone of General Electric.  
                       Dan is going to go over the methodology
           and some of the acceptance criteria, and part of the
           approach that was used for the extended power uprate.
                       I will go over the results and some of the
           conclusions that we had reached, and with that, I will
           turn it over to Dan Pappone.
                       MR. PAPPONE:  For the for the ECCS
           analysis methodology, we used the SAFER/GESTR-LOCA
           methodology for performing LOCA analysis.  We applied
           it as it was outlined in the ELTR, and we did
           basically a full scope analysis, and I will get into
           a little more of the particulars, because we are
           moving from the previous version of the code for the
           way we had applied it for Quad Cities, and we are
           essentially changing the fuel vendor of the analysis
           for the Dresden plant.
                       DR. SCHROCK:  My question earlier about
           the licensing basis.  I had this specific thing in
           mind.  The current basis is also -- rests on
           SAFER/GESTR calculations, using the provisions of SECY
           83-472; is that right?
                       MR. PAPPONE:  Right.  Well, the current
           analysis for the G.E. fuel in Quad Cities.
                       MR. HAEGER:  Right now Dresden uses
           Siemens fuel, and they have a Siemens analysis
                       DR. SCHROCK:  Which is different.
                       MR. HAEGER:  Yes.
                       MR. PAPPONE:  And because we are bringing
           the Quad Cities analysis up to date, and we are
           bringing Dresden into the SAFER/GESTR methodology, we
           did do a full-scope analysis for the plants, and when
           we do that analysis, we analyze the break spectrum
           using a nominal set of assumptions to determine the
           limiting break location, and limiting break size, and
           the limiting single failure.
                       And once we establish that, we calculate
           a licensing basis peak clad temperature using the
           required models from Appendix K.  This is the process
           that is outlined in SECY 83-482.
                       And in order to demonstrate that licensing
           basis PCT has sufficient conservatism, we also
           calculate an upper-bound peak clad temperature for
           limiting nominal case.
                       DR. SCHROCK:  In all of these descriptions
           of many analyses that have been performed, the results
           seem to be given in sort of a simple narrative
           description that things are well within the existing
           range or increase only by insignificant amounts, as
           opposed to showing us quantitatively what the results
           are, and what the range of investigations span, and
           how many there were, and things of this nature.
                       I would think that we need to hear some of
           those details to have a better understanding of do we
           buy in or don't we.  Do you follow me?
                       MR. PAPPONE:  Yes, I understand.
                       MR. HAEGER:  We actually have some of
           those comparisons in our upcoming slides, but as far
           as --
                       DR. SCHROCK:  Well, my reading of the
           thing is that it is a pretty broad brush description
           of how you comply with an existing set of regulatory
           limits that are imposed on you, as opposed to a
           technical evaluation of how the thing performs under
           these new conditions.
                       MR. PAPPONE:  We did perform that
           technical evaluation.  
                       MR. FREEMAN:  This is John Freeman.  I
           think I can address that.  What was great about this
           analysis was that it gave us a chance to do a complete
           new analysis to cover all four of those units, and we
           very carefully chose all the emergency core cooling
           performance inputs, and we ran it before the power
           uprate and after the power uprate.
                       And that's where the difference is very
           small.  With the same fuel type, all the same inputs,
           and the only difference being the power level for the
           dba, and we are going to go over this here in a minute
           to talk about for the dba, the temperature doesn't
           change that much.
                       Most of the impact due to power uprate is
           in the small break analysis, and we will go over that
           in a little bit.  But we will also talk a little bit
           about the fuel aspect, which is something that you
           wanted to be discussed.
                       When we are finished, maybe you could see
           if you have any more questions on this.
                       DR. SCHROCK:  Sure.
                       MR. PAPPONE:  The prime purpose of doing
           the analysis is to demonstrate that the plant is in
           compliance with 10 CFR 50.46, and acceptance criteria,
           and peak clad temperature, local oxidation for wide
           water reaction, coolable geometry, and long term
                       We do the plant specific analysis for the
           peak clad temperature, and local oxidation of the core
           wide metal-water reaction; and coolable geometry and
           long term cooling we have addressed generically in the
           SAFER/GESTR methodology.
                       The primary parameter of interest is the
           peak clad temperature, and we have to keep the peak
           clad temperature below 2200, which is the 50-46
           acceptance criterion.
                       And out of the SECY methodology, and the
           SECY approach, we also have to demonstrate the
           licensing PCT is greater than the upper bound PCT, so
           that we have demonstrated that licensing PCT we
           calculated is sufficiently conservative.
                       And then as part of the SER conditions
           that were imposed on the SAFER methodology, as part of
           that approval, we have a limit on the upper bound peak
           clad temperature of 1600 degrees.
                       And that was based on the test data that
           was supplied for the code qualification and the
           application methodology calculations that we had in
           the generic LTR for the SAFER methodology.
                       CHAIRMAN WALLIS:  You show here two
           different things for Appendix K and licensing basis. 
           Aren't they the same thing?
                       MR. PAPPONE:  The licensing basis PCT is
           essentially a statistical summation of the nominal
           Appendix K, plus some additional plant variable
           uncertainty terms.  
                       So in the practical sense, it is the
           Appendix K temperature, plus a small ADS.  That ADS
           picks up a few terms that aren't in the Appendix K
           calculations.  So it ends up being slightly higher.
                       Now, back to the actual scope of analysis
           that we did.  We did a full scope SAFER analysis for
           bringing the G.E. 9 fuel, the G.E. fuel that is in
           Quad Cities, and we are bringing that up to the
           current analysis process procedures and code.
                       We are also applying the SAFER methodology
           to the Siemens fuel that is in both Dresden and Quad
           Cities.  So at the end of all of this, we have got one
           common analysis basis for both units, and for all the
           fuels in the units.
                       We did all of the analyses, the full break
           spectrum analyses, assuming G.E. 14 fuel, because that
           was the hottest fuel that we were looking at.  That
           was fuel that was giving us the highest temperatures.
                       DR. SIEBER:  That is 10 by 10 fuel?
                       MR. PAPPONE:  That is a 10 by 10 fuel.
                       DR. SCHROCK:  And that is an equilibrium
                       MR. PAPPONE:  When we do the analysis, we
           are assuming an equilibrium loading.
                       CHAIRMAN WALLIS:  
                       DR. SCHROCK:  And you have a basis for
           concluding that that is the worst situation?
                       MR. PAPPONE:  Yes.  During the -- the two
           places that we look at a transition, versus
           equilibrium core, and during the initial blow down and
           core flow coast down that would affect the boiling
           transition time, that is once place that could be
                       And then the other places during the
           reflooding.  The fuel bundle design is such that it is
           hydraulically compatible.  There isn't much of a
           difference in one fuel bundle to the next, because
           they have got to be able to co-exist and intermixed
                       So there is very little hydraulic
           difference between the two, and you put a bundle in
           that has a lot higher resistance, or otherwise it will
           be starved and be too limiting locally, where we can't
           put in a bundle that has got a low resistance that
           will steal flow from the existing bundles.  
                       So we tend to even things out that way,
           and then the operating limit CPR will take care of any
           small differences from one bundle to the next one, and
           fuel type to the next.
                       DR. SCHROCK:  For your peak clad
           temperature, your decay power is certainly a
           consideration, and so the different points in the life
           of the core and the refueling changes, and all of
           those considerations, I guess my questions would have
           been more appropriate a year ago when we were talking
           about the generic aspect of the thing.
                       I tried to ask it then, and I didn't get
           a very satisfactory answer, but my knowledge of it
           doesn't come really from discussions in these current
           meetings.  It comes from more than 10 year old memory
           of discussions that we had when that methodology was
           bring developed.  
                       MR. PAPPONE:  Right.
                       DR. SCHROCK:  I really think that you owe
           an explanation of how these changes in the fuel
           characteristics impact what you have done to come to
           the methodology that is employed in applying the ANS
           standard to get the decay power curves that you are
           using in these analyses.
                       And they must be different now than they
           were when they were developed for the original cores
           that existed 15 years ago.  
                       MR. PAPPONE:  The key assumption for the
           decay heat is that we are using a nominal -- say mid-
           cycle exposure, and when we are doing the upper bound
           calculation, we do have the two sigma uncertainty on
                       DR. SCHROCK:  But how do you get to that,
           that's what I am talking about, and my recollection of
           it is that you took a lot of different core
           compositions typical of what would occur in the life
           of the core, and you calculate the K-power using the
           ANS standard, and you evaluate the uncertainty using
           the uncertainty values given there for those
           conditions that you did a Monte Carlo evaluation.
                       And it came to some kind of generic curve,
           which was then applied essentially in all of the many
           evaluations that you have described here, for example. 
           But it would be a different one now than it was then.
                       MR. PAPPONE:  No, we have not gone back
           and revisited that Monte Carlo analysis.  I am not
           aware that that Monte Carlo analysis being directly
           applied in the SAFER world.
                       DR. SCHROCK:  You are not aware of that?
                       MR. POST:  I don't think that ever was
           directly used in the SAFER world.
                       MR. HAEGER:  You are talking about the AMS
           standard decay heat curve.
                       MR. PAPPONE:  No, G.E. did an analysis on
           decay heat sensitivity, where we did go and look
           through --
                       DR. SCHROCK:  You see, what I understand
           that I am talking about gets at the difficulty that
           arises when something has been approved, and the
           industry can utilize that approval to move ahead and
           use that methodology and satisfy regulations in that
                       And I accept the fact that that exists,
           and it is a fact of life, and it is probably
           necessary.  But we are looking at the technical site
           of the thing here, and we want to understand are the
           conclusions that are being reached reasonable
                       Now, I find it difficult to come to grips
           with answering the question when confronted with a
           situation where many of the details that I think are
           necessary just don't appear in the discussions.
                       MR. PAPPONE:  We have just recently looked
           at the decay heat curve that we are using in the SAFER
           analysis, and come up with a new one for the -- we
           took a little bit different approach this time.  We
           had been going through and looking at the core average
           exposure of the fuel types, and the operating cycle
                       And coming up with a bounding decay heat
           value based on those parameters that would go into
           this the 79 model.  We have been using that in the
           containment analysis, because that analysis is one
           where we look at each individual part and make sure
           that each individual component is conservative.
                       So out of that family of curves that we
           have developed for the power uprate containment
           analyses, gone back and compared that with the decay
           heat curve that we are using in the SAFER analyses.
                       And on a nominal basis, considering that
           we are going from mid-cycle to end-of-cycle exposure,
           given those differences, the decay heat that we are
           coming up with now, that bounding envelope, is maybe
           a half-a-percent higher than what we had in the
           original SAFER curve.
                       DR. SIEBER:  Could I make an attempt to
           ask about the Appendix K --
                       MR. PAPPONE:  I haven't even gotten to the
           Appendix K yet.  The other pieces in the SAFER
           methodology, the licensing basis PCT, is based on an
           Appendix K PCT calculation, and that includes the 71
           decay heat, plus 20 percent.
                       So we have a large chunk of conservatism
           that we are introducing in the licensing PCT
                       DR. SCHROCK:  And that is done at the end
           for what you have established as the worst situation?
                       MR. PAPPONE:  Right.  But what we have
           done in looking at these containment decay heat
           curves, and comparing to what we are using today in
           SAFER, we are very close.  So I hope that answers your
                       DR. SCHROCK:  I hear what you are saying,
           and I am not saying that I don't believe it, but what
           I am saying is that I haven't seen the backup details
           that make it totally convincing to me.
                       DR. SCHROCK:  I understand.
                       DR. SIEBER:  Maybe we could back up for a
           second to the second bullet.  When you read that off,
           you made a statement that I think I misunderstood,
           which was you chose to use G.E. 14 fuel because it is
           the hottest fuel?
                       MR. PAPPONE:  Right.
                       DR. SIEBER:  I would think you mean in
           comparison to 9-by-9 fuel?
                       MR. PAPPONE:  Yes.
                       DR. SIEBER:  I would think that it would
           be the other way around, because you have more surface
           with 10-by-10 than you do with 9-by-9.  
                       MR. PAPPONE:  If we look at 9-by-9
           bundles, or why don't I take the G.E. 9 8-by-8 bundle
           if it is in there. 
                       DR. SIEBER:  Okay.
                       MR. PAPPONE:  We have got the maximum
           linear heat generation rate that we are allowed is
           14.4 kilowatts per foot.
                       DR. SIEBER:  Right.
                       MR. PAPPONE:  But we have only got 62 fuel
           rods, and they are depending on -- well, we have got
           60 fuel rods in there.  If we look at the G.E. 14
           bundle, its maximum LHGR is 13.4 kilowatts per foot,
           a kilowatt per foot lower.
                       But we have gone to 92 fuel rods in there,
           and so if we look at the power remaining slice, we
           have got a lot more power.
                       DR. SIEBER:  The density is --
                       MR. PAPPONE:  Right.  The total power is
                       DR. SIEBER:  But the PCT should be lower,
                       MR. PAPPONE:  Well, the PCT is --
                       DR. SIEBER:  Or what is the point of going
           to the 10-by-10 fuel?
                       MR. PAPPONE:  It can pack more energy into
           that bundle.
                       DR. SIEBER:  For a given set?
                       MR. PAPPONE:  For the nuclear site, yes.
                       DR. SIEBER:  For thermal conditions?
                       MR. PAPPONE:  Right.  And PCT is primarily
           driven by the LHGR, but the average planer power is
           also secondary, but still significant, input.  
                       So, yes, we would expect if we went and
           looked at an 8-by-8 bundle, and dropped the LHGR, we
           are going to see a large drop in the PCT, a
           significant drop.  But because we have gone to almost
           half again as many fuel rods in that plane, the power
           is up about 12 or 13 percent, 12 or 15 percent higher.
                       DR. SIEBER:  Well, it should be up 17
           percent if that is what your core average power
           increase is.  But your surface probably only goes up
           10 percent, right?
                       MR. PAPPONE:  When we do the analysis, we
           put that hot node -- the hot rod and the hot node
           right on its LHGR limit.  
                       DR. SIEBER:  Okay.
                       MR. PAPPONE:  So that doesn't move around. 
           The hot bundle power that we use in the analysis
           doesn't change.  The average bundle power will change
           with the power uprate.  
                       But when we put that hot node on full
           power, that is when I am saying the power level is
           about 12 to 13 percent higher for that node.  So we
           end up with a little higher PCT because of that.
                       DR. SIEBER:  Thank you.  That clarifies
           that for me.
                       MR. HAEGER:  We didn't finish this slide
           I don't think.
                       MR. PAPPONE:  Okay.  So we did all of the
           analyses for G.E. 14 fuel type, and the full break
           spectrum, non-recirculation line break, like steam
           water, and feed water, and single failure evaluation.
                       And once we establish limiting cases, we
           went back and evaluated those limiting cases using
           legacy fuel types, Siemens fuel, and the older G.E. 9
                       And we also did a sensitivity study for
           the power uprate.  We did all of these analyses at
           power uprate conditions.  We went back and analyzed a
           case of current power condition, where the only
           changes in the analysis were the reactor operating
           conditions.  So we had a true what is the impact of
           power analysis on that.  
                       CHAIRMAN WALLIS:  Which PCT are you
           showing us that you did this analysis for different
           fuels?  Which PCT are you actually showing us?
                       MR. PAPPONE:   The PCTs are the G.E. 14
                       CHAIRMAN WALLIS:  And the others are
                       MR. PAPPONE:  Right, except for the upper
           bound, we had a little larger sensitivity in the upper
           bound for the Siemens fuel.  So the upper bound PCT
           that we are showing is a little bit higher than the
                       It is based on the Siemens 9-by-9 fuel,
           and that was a little higher than the G.E. 14 fuel. 
           But the other temperatures are the G.E. 14.
                       DR. SIEBER:  Right.  Now, let me ask
           another question.  As you march through the next 2 or
           3 fuel cycles, you are going to have a mixture of
           legacy fuel and G.E. 14 fuel, which sort of tells me
           that when you do your reload safety analysis, unless
           you do some pretty fancy things in the fuel design
           space, that you won't achieve the extended power
           uprate for a couple of cycles.  Now, is that true or
           not true? 
                       MR. FREEMAN:  This is John Freeman.  I
           think the question as I understand it was because we
           don't have a full core G.E. 14, we are not going to be
           able to achieve --
                       DR. SIEBER:  Yes, and is that true or not.
                       MR. FREEMAN:  No, that is not true.  They
           are essentially operating strategies for the first
           reload cycle by the enrichment and the guideline
           choices that will allow us to hit the expected
                       Now, something that you have to realize is
           that we are not going to be operating that unit at
           2957 right on the money for the whole cycle.  We will
           be just like John mentioned.  We will be cycling the
           reactor power up and down to meet maximum generator
                       So that is all factored into the reload
           analysis for any particular cycle.  But it is done 
           -- obviously the safety analysis is always done at the
           license conditions, although the energy design will be
           for what we expect to operate at.
                       DR. SIEBER:  Now, for a two year cycle,
           and changing the fuel -- the number of fuel rods per
           assembly, I wold presume that the enrichment has to go
           up and to control it you have to add more guidelines?
                       MR. FREEMAN:  That's right.
                       DR. SIEBER:  Doesn't that place more
           pressure on your core shutdown margin?
                       MR. FREEMAN:  The core is designed to meet
           all of its core shutdown margin criteria.  
                       DR. SIEBER:  Well, I understand that, but
           the pressure -- the more that you go in that
           direction, the harder it is to guarantee to meet core
           shutdown requirements; is that true or not true?
                       MR. FREEMAN:  No, actually every core is
           designed to meet that criteria.  So if the design
           doesn't meet the criteria, it is not used.
                       DR. SIEBER:  Well, yes, I understand that.
                       MR. FREEMAN:  So it is a design process. 
           You either hit the target every time or you don't
           operate that particular design.
                       DR. SIEBER:  Well, there is trade-offs
                       MR. FREEMAN:  Yes.
                       DR. SIEBER:  All of your fuel parameters
           fit in some kind of a regulatory design box, and
           somehow or other you have got to get it in there, and
           the way you do it is to spend money, right?
                       MR. FREEMAN:  That's right.  You have to
           put --
                       DR. SIEBER:  That is usually one of the
           trade-offs.  And I also would imagine that the fuel
           would be most reactive sometime other than the
           beginning of life, and obviously not at the end of
           life; is that true also, because it is a balance
           between remaining enrichment, versus remaining
           venerable poisons?
                       MR. FREEMAN:  Where you get into the
           transient analysis Chapter 15 type world, which is
           apart from this LOCA stuff, yes, the particular core
           can be more reactive from a standpoint of a void
           coefficient, a doppler coefficient, and all of that is
           taken into account.
                       DR. SIEBER:  So about 30 percent of the
           cycle lifetime is usually when it is most reactive?
                       MR. FREEMAN:  It depends on the specific
           design and the goals that are being met for that
           design, and whether it is a spectral shift core, or
           whether it is some other goal.  
                       It can change, but it is all within the
           approved methodology, and the operating limits and to
           include all of that, as well as the LHGR and upper
           hydro limits are all protected for any particular
           design.  And that covers the entire exposure for that
                       CHAIRMAN WALLIS:  I suspect that we are
           getting behind on time; is that not the case?
                       MR. FREEMAN:  Yes, a little bit.
                       DR. SIEBER:  I should not ask any more
           questions I guess.
                       CHAIRMAN WALLIS:  Well, if you are getting
           the right answers --
                       DR. SIEBER:  Well, I understand the
                       MR. FREEMAN:  All right.  Let's go on with
           this slide then.  The approach as Dan mentioned
           calculated full spectrum as required by Appendix K. 
           I would point out that the DBA, which is a break of
           the recirculation section line, was a limiting case
           for this analysis.
                       Of course, small breaks and other selected
           breaks were evaluated, and per Appendix K, the
           limiting single failure was determined and it is the
           diesel generator failure.  
                       And on page 30, I will just go over some
           of the results that I --  
                       CHAIRMAN WALLIS:  I guess I thought when
           I read the SER that the steam line break brought the
           drywell air and shell temperatures very close to the
           limits, and yet you said --
                       MR. HAEGER:  This would not be for the
           LOCA analysis, but for peak clad temperature.
                       CHAIRMAN WALLIS:  It is peak clad
           temperature that is the limiting analysis, but for the
           containment, it may be something else.
                       MR. HAEGER:  That's correct.
                       CHAIRMAN WALLIS:  Now, is this true that
           this upper bound PCT is exactly 1600 Fahrenheit? 
           There must be some kind of a do-loop in this program.
                       MR. PAPPONE:  Well, no.  Well, actually
           there is a do-loop in the process, and that's where
           were if we do calculate a value above 1600 degrees,
           and we run out of fancy tricks to bring it back down
           to 1600 degrees, we have imposed a map of outer limit
           on the plant to keep the PCT below 1600 degrees.
                       In this case the calculated answer came
           out to be just below the 1600 degrees.  What we do
           when we report these temperatures, we run the
           calculated number up to the next 10 degrees, because
           I don't want to say that I calculate that number to
           four significant factors.
                       CHAIRMAN WALLIS:  Is this what determines
           the 2957 megawatt thermal?
                       MR. PAPPONE:  No.
                       CHAIRMAN WALLIS:  It's not? 
                       MR. PAPPONE:  Even if we had to impose a
           map of outer limit, and keep the fuel from going up to
           the 13, there is still margin in the core design world
           to absorb that without affecting the overall plant
           power uprate.
                       CHAIRMAN WALLIS:  What is the upper bound
           PCT with the existing power level?
                       MR. FREEMAN:  The upper bound PCT with the
           existing power level?  I think I have it here.
                       MR. PAPPONE:  Do you mean current
           licensing basis?
                       CHAIRMAN WALLIS:  Yes, current licensing
                       MR. FREEMAN:  I believe for Quad Cities it
           is below 1600. 
                       CHAIRMAN WALLIS:  Well, it better be, yes,
           but what is it?  It just seems high to me.  When we
           were looking at Duane Arnold, I don't think that we
           had anything like such a high PCT.  Why does it come
           so high in this case?
                       MR. PAPPONE:  I believe there is a big
           difference between the Dresden and Quad plants and
           Duane Arnold.  Duane Arnold is a very small vessel,
           and a very small core, and as a result, when they did
           the plant design, they used a smaller recirculation
                       Their recirculation pipe diameter is a 22
           inch pipe, and Dresden and Quad Cities, and the rest
           of the BWR-3s and 4s, it is 28 inch pipe.  So we are
           looking at for Duane Arnold, their break size is about
           60 percent of the Dresden and Quad.
                       And if we looked at the Appendix K PCTs
           for the two plants, if we looked at Dresden's and
           Quad's 60 percent and Duane Arnold's hundred percent
           break size, they are fairly close.  
                       CHAIRMAN WALLIS:  Could you get that
           number that I was asking about, the current licensing
           basis upper bound PCT?  I think it ought to be on one
           of your transparencies, but I am not sure it is.
                       MR. FREEMAN:  We will get back to you on
           that.  Okay. I think we are on page 30.  What we are
           looking at here --
                       DR. SCHROCK:  Excuse me, but you mentioned
           the question of accuracy on the PCT.  There is also
           the question of accuracy on the power level of the
           plant.  When you talk about 1957 or whatever the
           number is, plus or minus what on that?
                       MR. PAPPONE:  The Appendix K calculations
           include the 2 percent core power, and also on the
           linear heat generation rate, peak linear heat
           generation rate, and that is also factored into the
           initial CPR that is used in the analysis.
                       DR. SCHROCK:  No, what I am asking is how
           accurately do you know what the true thermal power is
           in the plant?
                       MR. PAPPONE:  Well, it is within that two
           percent and --
                       MR. HAEGER:  That is what 90 percent is
           for, is the uncertainty.
                       MR. PAPPONE:  Right.
                       DR. SCHROCK:  Well, that is a nominal
           value that was written into law a long time ago, but
           that isn't the true uncertainty in what you know to be
           the case.  So what I am asking is what is your known
           accuracy of thermal power of the plant at any given
                       DR. SIEBER:  It is generally one percent,
           right?  It comes out of a calimetric calculation,
           which used to be 2 percent, and that's why they put
           the 2 percent adder on to the core thermal power when
           it improved their ability to calculate that with
           improved flow instruments and temperatures.
                       MR. HAEGER:  Right, and in fact many
           plants of course are taking small uprates because they
           are demonstrating their uncertainty -- 
                       DR. SCHROCK:  They have reduced that
                       MR. HAEGER:  Right.
                       DR. SIEBER:  So the increment of margin
           that is in these calculations fully encloses the
           uncertainty of the calimetric calculation, at least in
           my opinion?
                       MR. HAEGER:  Yes. 
                       MR. FREEMAN:  Okay.  Page 30, these are
           the results for the LOCA analysis; a peak clad
           temperature of 2110 degrees, which is less than the
           5046 limit at 2200.  
                       As Dan mentioned before, we talked a lot
           about the upper bound and I won't go into that
           anymore.  The local oxidation was 6 percent, which is
           below the 17 percent limits for 5046.
                       Similarly, the core wide metal-water
           reaction was .1 percent, and it is well below the one
           percent limit, and of course the other 5046 criteria
           are met.
                       What this analysis showed that was done
           for the PSAR was that the effect of the power uprate
           on peak clad temperature was less than 10 degrees, and
           that is consistent with what GE has seen with other
                       CHAIRMAN WALLIS:  And so going back to my
           question before then, that means that on the current
           licensing basis, it is something like 50.90 something?
                       MR. FREEMAN:  The current licensing basis
           does not have G.E. 14 fuel.
                       CHAIRMAN WALLIS:  Like I was saying the
           EPU effect on PCT less than 10 degree fahrenheit, that
           presumably means upper bound PCTs is 1590.
                       MR. FREEMAN:  Well, remember that we
           stated earlier that this comparison was done strictly
           with G.E. 14, and the only change being the power
           uprate.  That was for purposes of determining what the
           effect on PCT was of the increase in power.
                       So with the different methods and fuel
           types that the other plants currently have, that 10
           degrees wouldn't apply that difference.
                       CHAIRMAN WALLIS:  So the effect of fuel
           type is some other number of degrees fahrenheit, which
           we don't know here?
                       MR. FREEMAN:  That is right.
                       CHAIRMAN WALLIS:  But you are saying it is
           a small effect, and the message that you are trying to
           convey would seem to me is that EPU has small effect
           on PCT, and it may well be that the change in fuel
           type has a bigger effect than the EPU.
                       MR. HAEGER:  That is precisely right.
                       MR. FREEMAN:  That's right.  
                       CHAIRMAN WALLIS:  So we maybe ought to be
           discussing changes of fuel type, and that is another
           meeting altogether isn't it?
                       DR. SIEBER:  Yes.
                       MR. FREEMAN:  Yes.
                       MR. HAEGER:  Yes, it is a separate license
           amendment request that we have before the Commission.
                       MR. FREEMAN:  Okay.  Moving on to page 31,
           I just want to apologize for this first bullet here.
           It says that the EPU effect on large break LOCA, and
           in the subbullet, really as you mentioned, sir, it is
           the G.E. 14 effect on the large break LOCA that
           motivated us to make a set point change in the swing
           bus delay timer.
                       And it really wasn't the power uprate. 
           This was something that came from the use of G.E. 14
           fuel, and I think that John mentioned that swing bus
           set point change already.  
                       Whereas, the really big effect of the
           power uprate was on the small break LOCA and that was
           expected because of the higher decay heat values.  
                       To summarize, before power uprate, we
           could afford to have one ADS value out of service, and
           we could get adequate depressurization for small
           breaks with four ADS valves.
                       However, at extended power uprate
           conditions, the analysis showed that we needed all
           five of the five ADS valves to operate in order to
           keep our upper bound PCTs below the 1600 degrees.  
                       CHAIRMAN WALLIS:  Does this only affect
           the risk?
                       MR. FREEMAN:  I believe the impact upon
           the risk will be discussed.
                       MR. HAEGER:  We will be discussing that
                       MR. FREEMAN:  Moving on to page 32.  In
           conclusion, the emergency core cooling analysis
           methodology that is being used is conservative, as
           well as accepted by NRC.
                       The licensing basis PCT is a conservative
           way of calculating the result based on Appendix K
           models.  In conclusion, after meeting all 5046
           criteria, the emergency core cooling system
           performance is acceptable at the power uprate
                       And unless there are any other questions,
           I will introduce Tim Hanley, and he is going to go
           over the thermal-hydraulic stability.
                       CHAIRMAN WALLIS:  Thank you very much.  
                       MR. FREEMAN:  You're welcome.
                       MR. HANLEY:  I am Tim Hanley, and I am a
           senior reactor operator at the Quad City station. 
           Jason Post of General Electric will be talking about
           the background methodology and analysis results, and
           then I will be covering operational aspects and
                       CHAIRMAN WALLIS:  I would like to ask
           where we are on the presentation, and when I discussed
           with Exelon earlier, and we thought that we could have
           a break before the risk evaluation, but I noticed that
           we don't even seem to be about half-the-way there yet.
                       MR. HAEGER:  What we thought that we would
           try to do is to get through the slide and all the
           analysis on that slide that stated the selected
                       CHAIRMAN WALLIS:  Well, that will get us
           up to slide 70 something, and we are only to 34 now.
                       MR. HAEGER:  Yes.
                       CHAIRMAN WALLIS:  Can we do that in half-
           an-hour or 40 minutes, or something?  We may have to
           break before we intended to break.
                       MR. HAEGER:  And we can certainly work
           around whatever break time you want.
                       CHAIRMAN WALLIS:  We are behind where we
           thought we would be.  
                       MR. HAEGER:  Yes.  
                       MR. HANLEY:  With that, I will turn it
           over to Jason Post of General Electric.
                       MR. POST:  This is Jason Post.  Dresden
           and Quad Cities are still operating with a BWR owners
           group interim corrective actions in place.  They have
           -- the ICAs provide manual prevention and suppression,
           and they have been in operation for something over 10
           years now with those in place.
                       They have not yet implemented the
           stability solution, and the stability solution that
           they have selected is Option 3, and Option 3 is a
           robust detect and suppress solution. 
                       It requires some new hardware, the
           oscillation power range monitor, the OPRM.  The OPRM
           has been installed, but it has not been operational
           yet, partly as a result of the Part 21 notification
           that G.E. issued earlier, this summary of the DVOM
                       It is a robust detection algorithm that
           looks at LPRM signals, and determines when an
           oscillation occurs, and if the oscillations go up to
           a set number of oscillations in a row, called the OPRM
           count, and the amplitude reaches a certain set point,
           and that occurs within what is called the trip enabled
           region, then the OPRM will give an immediate SCRAM.
                       The next slide shows the ICA power flow
           map, with the ICA regions on them, and the key thing
           to note here is that the absolute power and absolute
           flow on the region boundaries has not changed.
                       They have been effectively rescaled so
           that you maintain the same absolute power and absolute
           flow on those boundaries.  And just the way that the
           ICAs work, ICA in Region 1 is an immediate SCRAM
                       So if they were to get a flow run back
           into that region, there is an immediate manual SCRAM
           by the operator based upon simply being in that
                       It is not -- it doesn't require
           determining that an isolation has occurred or
           anything.  You get an immediate manual SCRAM.  Region
           2 is an immediate active region, and so if there is a
           run back into Region 2, the operator immediately
           inserts control rods or reduces core -- I'm sorry,
           increases core flow to exit that region.
                       Region 3 is called a controlled entry
           region, and under the Owners Group ICAs, you are
           allowed to enter that region if you have a stability
           control.  For example, high core boiling boundary,
           which makes the core more stable.
                       And actually for Dresden and Quad Cities,
           they have just assumed or have included Region 3 as
           part of Region 2.  So it makes the immediate exit
           region include both of those two regions.  
                       CHAIRMAN WALLIS:  And where does this
           Option 3 OPRM -- well, where does that fit in that map
           in terms of where it would SCRAM the reactor?
                       MR. HANLEY:  That is shown on the next
                       MR. POST:  Let me just say that before we
           go to the next slide, to remember that the purpose of
           the ICAs is to prevent a reactor instability, and if
           one does occur, to have a manual SCRAM.
                       So it is drawn to be a limiting condition
           for where you would expect instability to occur.  
                       CHAIRMAN WALLIS:  I would expect the
           limits of his OPRM to be sort of inside the other
                       MR. POST:  It actually needs to be larger.
                       CHAIRMAN WALLIS:  Larger?
                       MR. POST:  Yes, it needs to be actually
           larger, and the reason is that because you want to 
           make sure that it encompasses the area in which an
           instability could possibly occur.
                       CHAIRMAN WALLIS:  Well, it encompasses it,
           but where you actually predict that it is likely to
           SCRAM the reactor is going to be a smaller region than
           where the operator would do it.
                       MR. POST:  Yes.
                       CHAIRMAN WALLIS:  Otherwise, it would
           always be done automatically.
                       MR. POST:  That's correct.
                       CHAIRMAN WALLIS:  So the actual -- what
           you expected to really happen is a fairly small region
           up in the corner there somewhere? 
                       MR. POST:  Yes.  If you were to draw a
           line of constant decay ration, and if you could go to
           the next slide, please.  The line of constant decay
           ratio would be somewhere in here.
                       CHAIRMAN WALLIS:  It is way up in there. 
           Right.  Right.
                       MR. POST:  And so that is the reason that
           you would expect oscillation would actually occur, and
           the OPRM and trip enabled region is defined to be well
           outside that region.
                       Again, for the trip enabled region, what
           we do is rescale the region boundary so that the
           absolute power and flow condition is maintained the
           same as the pre-uprate condition.
                       MR. BOEHNERT:  When is the Option 3 going
           to be implemented?
                       MR. HANLEY:  For Quad Cities and Dresden,
           they will implement that when the Part 21 notification
           has been resolved.  Even plants that have already
           enabled that have gone back to the ICAs as a backup
           because it is non-conservative in some points.  So as
           soon as the Part 21 issue is resolved, we will be trip
           enabling that system.
                       MR. POST:  We are working with the BWR
           owners group on that, and it will probably be a year
           from now before it is actually -- the new subpoints
           are defined and it is ready to go.
                       Just moving on to the next page then, on
           the analysis results, we did a demonstration analysis
           for the demonstration EPU core on the OPRM setpoint
           simply to demonstrate that that calculation can be
                       It is a cycle specific calculation and is
           done for each reload.  The three elements of it are
           the hot bundle oscillation magnitude, and that depends
           upon the OPRM hardware.  It is unaffected by EPU,
           MELLLA or G.E. 14.  
                       It is strictly related to the LPRM
           configuration.  The second part is the CPR change
           versus oscillation magnitude, and that is known as the
           DIVOM curve, and that is currently being revised by
           the owners group and G.E.
                       And the third part is the fuel specific
           CPR performance and limits which are addressed in the
           cycle-specific analysis.  So we use all those elements
           to calculate what the OPRM set point is that provides
           safety limit protection for our reactor instability.
                       CHAIRMAN WALLIS:  Well, that doesn't mean
           anything ot me at all.  That is so full of acronyms
           and -- 
                       MR. POST:  I'm sorry?
                       CHAIRMAN WALLIS:  It didn't mean anything
           to me at all.
                       MR. POST:  Well, I'm sorry.
                       CHAIRMAN WALLIS:  I am not sure that you
           can make it clearer, but --
                       MR. POST:  The OPRM is the oscillation
           power range monitor, and that is the new piece of
           hardware that you install specifically for Option 3.
                       CHAIRMAN WALLIS:  Yes, I understand that.
                       MR. POST:  And it has an amplitude sub-
           point, and so as the oscillation grows, it is a
           normalized value --
                       CHAIRMAN WALLIS:  So that is on the
           reactor when the oscillation is big enough, and I
           understand that.
                       MR. POST:  Yes.
                       CHAIRMAN WALLIS:  But this business about
           the DIVOM curve.
                       MR. POST:  DIVOM stands for delta CPR over
           initial CPR, versus oscillation magnitude.  Hence the
           acronym, DIVOM.  And that that is, is just how much
           does CPR change as a function of the fuel type.
                       What we found for the Part 21 when we did
           the Part 21 notification is that we had a generic
           curve, and we found out that we were a little bit
           overestimated in the generic applicability of that
           curve, and some specific factors were not fully
                       And so that resulted in the Part 21
           notification, and we are developing what a new DIVOM
           curve should be.  It is likely to be more plant and
           cycle specific, and factor in the specific parameters
           that affect that curve.
                       CHAIRMAN WALLIS:  Well, if you are
           developing something, what has that got to do with
           application for a license now?
                       MR. HAEGER:  We should probably go back
           and put this in perspective.  We are going to start up
           using interim corrective actions, which is what we
           have been operating on for quite some time.  And what
           we are trying to show in this slide, number 36, is
           that those interim corrective actions are applicable
           to the EPU power level.  
                       And so really until this Part 21 issue is
           resolved, all this discussion about the OPRM system
           and these DIVOM curves is somewhat moot right now.  
                       CHAIRMAN WALLIS:  So does that mean that
           we have to move on?  Now, this is the drunken man's
           walk; is that what that is?
                       MR. HANLEY:  This is Tim Hanley again from
           Exelon.  I am going to go over some operational
           considerations in discussing stability.  What you see
           on the screen now is a picture of the power flow curve
           with the actual data from our last Unit 2 start up.  
                       Two real operational concerns when talking
           about thermal hydraulic stability is, first, we want
           to avoid entering the regions of potential
                       The real concern there is do you have
           enough room between your cavitation interlock line 
           down here, which is the point at which you can
           increase your recirculation pump speed, and the bottom
           of the instability region.  It is quite a bit of
           margin and not difficult to avoid that region during
           the start-up.
                       So that is the initial thing that we do,
           and the other consideration is what do you do if you
           enter one of the regions of instability, or potential
           instability inadvertently.  The recirculation pump
           trip is evaporating at a high flow control line at low
                       There is a potential if you are operating
           at low power, low flow, loss of heat core heating can
           raise your power levels in those regions.  So what do
           you do if you get there?  
                       Jason mentioned that you have two options;
           inserting rods or increasing flow.  Neither Dresden
           nor Quad Cities do we have increasing flow as an
           option.  We always insert rods to decrease your flow
           control line.
                       So if the operator gets in the instability
           regions, they will monitor for instabilities, and what
           they are looking for is about a two times change in
           the noise level on the nuclear instrumentation --
           SRMs, LPRMs, or ATRMs.
                       CHAIRMAN WALLIS:  Well, there is nothing
           new about extended power about this.  
                       MR. HANLEY:  No, the only thing different
           -- and maybe since we are running behind we ought to
           keep it at that, but the only thing is that the
           potential instability region has expanded, because we
           are going to higher power.
                       And that area that comes off of the top
           there that kind of jets out is a new region of
           instability, and anything above our current 108
           percent MELLLA region is new.
                       But the operator action flow won't change,
           nor will the OPRM change, when we install that.  The
           region will just be expanded.  So in conclusion,
           really we intend to start up with the ICAs in place
           that we have been operating under to implement the
           OPRM, and trip enable that when the Part 21
           notification is completely settled and we can do that
           at the right opportunity.
                       We have rescaled the instability region,
           and so we have maintained our absolute levels for when
           we say we are entering the regions of potential
           instabilities, and that power uprate doesn't
           significantly affect how we would handle instabilities
           and our analysis is acceptable for power uprate with
           thermal-hydraulic stability.  Any questions?
                       DR. SCHROCK:  Maybe it is not important,
           but there is a curious effect here on this particular
           curve.  It looks like you went up initially, and then
           you kind of dwelled for a while with rods in and out
           jingling a little bit.  Is that the way they really do
                       MR. HANLEY:  What you have got here -- you
           are talking about the 25 percent power level?
                       DR. SCHROCK:  Forty percent, 40 percent
           flow.  Well, 30.
                       MR. HANLEY:  And then it is about 25 or 30
           percent power.  WE do a lot of testing at that point,
           turbine testing, to verify all the turbine trip SCRAMs
           are all operational.  So we do end up staying at that
           power level for a while during a start up.
                       It is also kind of jagged.  I did get
           this, I believe, off of 15 minute increments of data. 
           So that is why it tends to jump around.  It is not a
           smooth curve because I didn't go to minute data.  
                       But there are certain points where we
           spend more time due to required testing, and that in
           particular is the turbine testing.  
                       DR. SCHROCK:  Well, can the thermal power
           change by as much as this spread and data point shows
           without rod movement?
                       MR. HANLEY:  Certainly.
                       CHAIRMAN WALLIS:  And another question
           becomes how about --
                       MR. HANLEY:  You are looking at flow
           though, right?
                       DR. SCHROCK:  Well, flow is constant
           there, that group of points that I am looking at.
                       MR. HAEGER:  I don't know that we can
           resolve them that clearly.  The resolution isn't --
                       MR. HANLEY:  You are looking just at that
           little glob of points in there?
                       DR. SCHROCK:  Right.  Yes.  I am curious
           about why they would stop there, and it looks like
           there almost was in and out rod jiggling.
                       MR. HANLEY:  What you really see is the --
           you are getting -- depending on how long you stay
           there, you will begin to see some zenon build in, and
           so you may be pulling some rods.  You may be adjusting
           recircs to compensate for that.  
                       And like I said, during this start up, you
           may sit there for as much as eight hours doing your
           testing.  So you will in fact be adjusting power at
           that point.
                       CHAIRMAN WALLIS:  And then there is the
           jingling around at the hundred percent core flow, and
           one has to wonder how much jingling around you would
           do if you got to Point D in your uprate.
                       MR. HANLEY:  Essentially, the way you can
           operate is that right now we have this band to operate
           in from our permanent 100 percent power out to the
           current 108 percent flow control line.
                       You operate on that line and adjust your
           recirc flow so that as your Zenon builds in, you will
           pull up to above the hundred percent flow control
           line.  Zenon builds in your adjust recirc pumps to
           stay at that same power level.
                       The operating band we will have is
           actually between charlie and delta up here.  So we
           will in fact be adjusting recirc flow at the higher
           power level or doing some power rod moves.
                       But we do have an operating region that we
           will be able to operate in so that the operators won't
           constantly be pulling control rods.  They will be able
           to make slight adjustments in recirc flow and maintain
           full power.
                       CHAIRMAN WALLIS:  But they still won't go
           over 2957 megawatts while they are doing that?
                       MR. HANLEY:  No, we won't go over 2957
           megawatts, and until we do modifications to the
           generator, it is unlikely that we will even get there.
                       We will actually be operating at a lower
           thermal power level because we will be limited by the
           capability of the generator.
                       MR. HAEGER:  But I think the point is that
           you do calimetrics frequently to determine that you
           are not over the --
                       MR. HANLEY:  Oh, certainly.  We have a
           computer program that warns us if we get within five
           megawatts thermal of our rated thermal power.  So the
           operators -- it runs on a -- every two minutes.  So
           they will --
                       CHAIRMAN WALLIS:  So it is definitely an
           upper bound.  I mean, it is almost the impression that
           is being given that with the line through that orange
           jiggling around that you can jiggle around some set
           point or something.  But actually the 2957, that is an
           upper bound isn't it?
                       MR. HANLEY:  Well, if you draw crosses,
           and the top of the crosses are all very much the same
           place.  So the actual data goes --
                       CHAIRMAN WALLIS:  But the top of the
           crosses would be the 2957 if you ever get there.
                       MR. HANLEY:  The middle of the cross.
                       MR. HAEGER:  The middle of the cross.
                       CHAIRMAN WALLIS:  The middle of the cross?
                       MR. POST:  This is just a plot in XL.
                       MR. HANLEY:  XL uses the point to put a
           cross at --
                       CHAIRMAN WALLIS:  Okay.  So it is not the
           line that is jiggling around.  All right.  Okay.
                       MR. HANLEY:  Are there any other
           questions?  With that, I will turn it back over to
           John Freeman and Jason to discuss ATWS.  
                       MR. FREEMAN:  Thanks, Tim.  We are going
           to talk about anticipated transient without SCRAM, and
           Jason is going to go over some of the methodology and
                       CHAIRMAN WALLIS:  I guess if you are using
           established methodology and assumptions we can skip to
           the results.  
                       MR. FREEMAN:  Surely.  
                       MR. POST:  That would be great.  We did
           have one slide in here on ATWS instability, or
           actually two slides that I am prepared to cover.  As
           we discussed previously when I was here for Duane
           Arnold, the two reports were NEDO-32047, which was the
           instability with no mitigation; and the 32164, had the
           instability with mitigation.
                       And our previous argument was that these
           generic studies were applicable to EPU and MELLLA, and
           there was some question about that.  We since our last
           meeting, we have done a sensitivity study at a more
           limiting condition.  
                       It is on a rod line actually above the
           MELLLA line.  It is for an EPU condition, and it is
           for G.E. 14, and we have finished the no mitigation
           study, and it showed a less severe fuel response than
           we showed previously in the topical report with no
                       In other words, it had less susceptibility
           to the extended dryout.  It still could experience the
           extended dryout, but it took a little bit longer time
           to get the oscillation that put it into that
                       So this confirms our expectation that the
           generic studies are valid for EPU and MELLLA, and
           confirms our expectation that the mitigation actions
           will be effective.
                       MR. FREEMAN:  Okay.  I would like to skip
           forward to page 47.  These are the results for the
           five criteria and the limiting event.  You can see
           over here the peak pressure of 1492 was below the
           acceptance criteria of 1500.
                       For the peak pool temperature, 201 was
           below this 202 degrees, which I think Mark may have
           mentioned was the TORUS attached piping limit that was
           analyzed for the LOCA.  
                       It turns out -- and you probably remember
           that 281 was a structural limit for the suppression
           pool.  But these results show that they are quite
                       CHAIRMAN WALLIS:  So you are again pushing
           the limit on pressure and temperature, the 1499 versus
           the 1500?
                       MR. FREEMAN:  This 1499 is for transition
           core, and that included -- all these analyses were
           done with exactly the same inputs, and they have
           conservatisms built in.  
                       So we would actually expect not to see a
           pressure like this.  That is a conservative number.
                       CHAIRMAN WALLIS:  But in terms of the
           criteria, you are just meeting the criteria.
                       MR. FREEMAN:  Yes, sir.  Of course, with
           the peak suppression pool temperature, it is very low,
           and the peak clad temperature is also very low, which
           has a negligible maximum local oxidation.  
                       So in every case for ATWS, which is a
           beyond design basis event, this demonstrates that the
           50.62 criteria can be met. 
                       CHAIRMAN WALLIS:  Doesn't this depend on
           valves opening and that sort of thing, and numbers of
                       MR. FREEMAN:  Yes.
                       CHAIRMAN WALLIS:  And do you have to have
           more valves open in this case than before, or is that
           a different --
                       DR. SIEBER:  It depends on the success
                       MR. FREEMAN:  The ATWS analysis takes
           credit for all the relief and safety valves as is
           typical for ATWS analysis.  
                       MR. HAEGER:  However, in the PRA study, we
           will be discussing --
                       CHAIRMAN WALLIS:  Yes, you need one more
           valve to show the open.
                       MR. HAEGER:  That's correct, and we will
           be talking about that.  
                       MR. FREEMAN:  Okay.  With that, I would
           like to introduce Norm Hanley, and he is going to talk
           about the piping analysis.  
                       CHAIRMAN WALLIS:  With the ATWS, there is
           no requirement about operator reaction time in any of
           the ATWS regulations?  It only appears in the PRA? 
           There is nothing in the --
                       MR. POST:  That's right.  There is nothing
           in the regulation that specifies what the minimum or
           maximum operator action time is.
                       MR. N. HANLEY:  Good afternoon.  I am Norm
           Hanley, and I am the test manager for the piping
           evaluations that were performed for the power uprate
           for Quads and Dresden City.  
                       I am going to present the methodology that
           was used to do the piping evaluation, and the actual
           impacts as a result of the EPU, and what the
           disposition and conclusion, and results of those
           evaluations that were performed.
                       The impact of the power uprate would be a
           change in the operating conditions, flow pressure and
           temperature in some of the fluid systems.  In order to
           evaluate those systems, we reviewed the plant specific
           criteria to identify those parameter bases for the
           existing analysis.
                       We also as part of that review identified
           what the original code that was used, the analytical
           techniques that are used consistent with the license
           spaces, and also the code allowables.
                       The one exception to this was that we
           developed some criteria for the main steam piping
           consideration for dynamic loads due to a turbine stop
           valve, and I will address that in my  presentation.
                       The conclusion in the initial review was
           that the majority of the piping systems were not
           impacted by the power uprate.  The methodology that
           was employed to evaluate those systems that were
           impacted was a simple evaluation to identify what we
           call a change factor.  
                       This looked at those parameters such as,
           for instance, in temperature, and if the temperature
           changed or the operating temperature would be higher
           for a power uprate, we simply looked at that delta
           change and compared it to the original analysis basis.
                       And if the comparison was the post-uprate
           versus pre-uprate was greater than 1.0 the ratio, then
           we would evaluate it further.  Any ratio less than
           1.0, the pre-uprate conditions were bounding, and no
           further analysis was required.  For minor changes in
           the parameter --
                       CHAIRMAN WALLIS:  There didn't go for
           pressure or anything like that.  This didn't go for
           vessel pressure?  This is just piping?
                       MR. N. HANLEY:  This is piping, correct. 
           Now, for minor changes, where the parameter change was
           between 1.0 and 1.05, again we considered the change
                       And this is based on a conservatism in the
           original analysis, and some of these conservatisms
           where the initial inputs were conservative, the
           combination of loads, and incorporating loads that had
           been changed for the power uprates for seismic and
           dead weight, and also due to the inherent analytical
           techniques where there were gaps between piping and
           pipe supports were not included.
                       DR. SIEBER:  Could I interpret this to say
           that if it was less than 5 percent, you didn't bother
           to find out where the conservatisms were, or whether
           it was conservative or not?  You just said it was
                       MR. N. HANLEY:  Right.  And that was based
           on experience with the piping systems and evaluations
           that we performed.  We have done a number of power
           uprates where we have used this application.
                       MR. HAEGER:  Realize that we are taking
           one parameter and if it changed five percent, there
           are all the other factors in the equation that we are
           seeing, there is conservatisms in there.  So that is
           the basis of that.  
                       MR. N. HANLEY:  I think when I present the
           systems that were impacted and where we did further
           evaluations, we will see what -- I think we can
           support some of that argument there.  
                       Where the change factors were greater than
           1.05, we did take the next step, which was to look at
           that ratio.  Let's say, for instance, the ratio is
           1.1, and we would take that parameter and scale the
           existing peak load up, and see if it was within the
           acceptance criteria of the code allowables.  
                       And gain if it was less than the code
           allowable acceptance criteria, the analysis was
           acceptable.  Now, for cases where we couldn't do that,
           we did go back and reevaluate or reanalyze the piping
           system, and if needed we would do modifications.
                       The most notable change area was the
           temperature change due to the TORUS border temperature
           increase.  The increase was approximately about a 20
           degree temperature change for the pre-uprate and the
                       We did have to do reanalysis and
           modification for this system.  However, the
           modifications were isolated primarily to piping
           supports, and in existing supports, we didn't have to
           add new supports.
                       Those changes resulted in like the
           replacing of U-bolts, the modification of the base
           plates, structural members, et cetera.  The most
           noticeable change was that we did have to replace the
           rigid support with a snubber to reduce the piping
           loads on the flange connection.
                       So I think that type of analysis, rigorous
           analysis that we did there, a significant change
           resulted in that.
                       CHAIRMAN WALLIS:  Were there any changes
           that ACRS needs to worry about?  I mean, changing
           bolts and snubbers --
                       MR. N. HANLEY:  These were minor
           components to the existing supports, and just to show
           that their load capacity could be handled.  The other
           significant change that we had was the main steam
           piping, where we incorporated the dynamic loads due to
           a turbine stop valve closure event.
                       The original design for Quads and Dresden
           is based on static load conditions outside
           containment, and a dynamic load condition inside
           containment for a safety relief valve-load.  It did
           not include the turbine stop valve loads.
                       We evaluated the impact of the uprate on
           a turbine stop valve closure event, and since we do
           increase flow approximately 20 percent, we felt that
           it would be prudent for us to include the impact of
           that turbine stop valve closure event.
                       The evaluation identified that there was
           significant impact on the loading on the piping system
           outside containment, as well as the piping supports
           and drywell steel on the inside of the containment. 
           The resulting evaluations required modifications.
                       CHAIRMAN WALLIS:  That's because the
           closure is rapid; is that it?
                       MR. N. HANLEY:  Yes, you have a very rapid
           hundred milliseconds or what it is, and so you have a
           significant on the change.  So the approach that we
           took to the evaluation of that was that we wanted to
           make sure that for a turbine stop valve closure event
           itself that we didn't have a defamation of the piping
                       And also we looked at it coupled with a
           seismic, and we wanted to maintain structural
           integrity with a seismic event resulting from a
           turbine stop valve closure.  
                       So the approach that we used was there
           would be no loss of structural integrity coupled with
           a seismic event.
                       DR. SIEBER:  Well, you probably had a
           number of stop valve closure events in the history of
           these two units.
                       MR. N. HANLEY:  Correct.
                       DR. SIEBER:  Did you get damage?
                       MR. HAEGER:  We have never seen damage.
                       CHAIRMAN WALLIS:  Well, damage in terms of
           broken snubbers is a pretty minor thing compared with
           a safety --
                       MR. D. HANLEY:  Right.  There was no
           identified or reported when we did the evaluations. 
           And again the piping system itself is -- that when we
           evaluated it and used conservative assumptions, then
           you would see the overload on the existing snubbers
           and supports.
                       So the result was that for the piping
           inside containment, the changes to the existing
           snubbers, we replaced some with higher capacity.  We
           had to replace some members with higher members.
                       We also had to evaluate the drywell steel
           which was supporting -- taking a load from the
           supports.  There we had to stiffen up the connections
           to take the increased load capacity.
                       The more significant changes were outside
           the containment, where the piping as I mentioned
           earlier was a static load design.  We did have to add
           supports to take the lateral loads.
                       The main supports were -- well, we put in
           specially designed clamps with a box frame support at
           the main steam header to take the load, and we also
           had some lateral guides through the G-line wall at
                       Quad Cities is similar, and we added some
           supports on the main steam lines, and these were more
           towards the main steam isolation valve in the tunnel. 
           Again, we used the specially designed clamps with
           vertical and horizontal struts.  
                       DR. SIEBER:  You would have had to do that
           whether you were doing an uprate or not, right?
                       MR. HAEGER:  As he said, they were not
           designed, originally designed for these dynamic loads. 
                       DR. SIEBER:  But they should have been,
           right?  I guess in '68, which is the code of record,
           it was not in the code of record?
                       MR. HAEGER:  That's correct.
                       CHAIRMAN WALLIS:  Okay.  Go to your
                       MR. N. HANLEY:  Yes.  The conclusion is
           that the piping analysis demonstrated that the piping
           will meet acceptable requirements based on the --
           consistent with the current licensing design basis.
                       CHAIRMAN WALLIS:  But you have made them
                       MR. N. HANLEY:  We made them acceptable by
           doing modifications in the TORUS attached piping area,
           and also we incorporated the TSV loads, and made those
           analyses acceptable as well.  
                       So the conclusion is that with the
           modifications and the reanalysis the piping systems
           will be adequate for an extended power uprate.
                       CHAIRMAN WALLIS:  I am inclined to think
           that we should go to this next one, reactor and
           internals, and perhaps take a break after that.
                       MR. N. HANLEY:  Actually, the next two fit
           real nicely together, and the second one can be short,
           but either way.
                       CHAIRMAN WALLIS:  Well, let's see how we
           do.  We are getting pretty close to the time where we
           are going to need a break.  So, let's go ahead with
           reactor and internals.
                       MR. N. HANLEY:  I would like to introduce
           Keith Moser now to discuss reactor and internals. 
           Thank you.  
                       MR. MOSER:  Hello.  My name is Keith
           Moser, and I am the reactor and internals program
           manager for Exelon, and I want I want to cover today
           is the scope and methods that we used to evaluate
           reactor and internals for power uprate conditions.
                       And the effect that EPU had on those
           components, and the modifications that John Nosko
           talked about earlier.  And then finally conclusions.
                       Before we even started the power uprate
           project, Exelon and G.E. had developed an asset
           management strategy that took into account the
           industry information both from the domestic fleet and
           G.E.'s worldwide experience, and compared that against
           what we had done in our inspection program and
           operating history at Dresden and Quad.
                       And we came up with susceptibility
           rankings for each one of our components, and at that
           point what we did is that we came up with inspection
           strategies, mitigation strategies, and finally repair
           strategies if we needed them.
                       Now, for EPU, we again went component by
           component and one of the first ones that I wanted to
           go over was the fluence issue that was just talked
           about earlier.
                       Now, back in 1992 -- and, John, if you
           don't mind holding that up.  Back in 1992, we wanted
           to take advantage of two co-case.  The first one was
           co-case 640, and the next one was co-case 580.  
                       And especially for Quad Cities and
           Dresden, it lowered our temperature at which we did
           hydro tests from about the 212 range by 50 degrees to
           55 degrees.  
                       And in doing this, we went back and looked
           at what fluence calculation was done in the past.  The
           fluence calculation of record was for the Southwest
           Research, and what they had done is that hey had
           actually taken capsule pools from all four units and
           the capsule pools ranged after they scaled them up
           from 3.5 times 10 to the 17th neutrons per centimeter
           squared, all the way up to 5.1 times 10 to the 17th
           neutrons per centimeter squared.
                       In our evaluations, we took the most
           bounding and said this is where we are going to do our
           fluence calculations for the 1999 and 2000 PT curves.
                       What we have come to find out after we
           have done the neutron transport calculation for power
           uprate is the following.  Yes, we are lower than what
           was previously put into the PT curves that was done by
           Southwest Research, but we have an explanation of why.
                       And I just got that from my expert, Gida
           Boo, and Sam Ranganath, and Brian Frue, and Betty
           Bramlin at G.E., and what we think has happened is
           when they modeled their capsule with their fluence
           methodology, they had it right up against the reactor
                       They did not take into account about a
           little over one inch gap and that difference is where
           we think a lot of this can be explained.  We also
           understand that the methodology at that point in time
           didn't require you to model the jet pump in the -- I'm
           sorry, the fast flux calculation.  
                       Those type of things make it not an apples
           to apples comparison.  Now, there are improvements in
           the methodology, and we are following the new NRC
           requirements, but we honestly think it is the spacing
           that they did not take into account for the capsule
                       CHAIRMAN WALLIS:  Now, tell me more about
           this.  The capsule, it is an experiment?  They put
           something in there?
                       MR. MOSER:  That is a sample capsule that
           he put right in the belt line region.  
                       CHAIRMAN WALLIS:  So it is an experiment. 
           You put something in.
                       MR. MOSER:  It is on a bracket that is
           held away from the vessel walk and the distance like
           I was saying is a little bit over an inch.  And if you
           don't model that, even though it is not that far, just
           the attenuation through that one inch gap, or 1.75
           inch gap, is enough to make a significant difference. 
                       MR. HAEGER:  Let me make sure that we have
           the right perspective on this.  When we applied for
           the EPU application, we used the G.E. improved fluence
           methodology that Keith is describing now.  That
           calculation showed that our fluence is actually lower
           than what we had projected.  
                       DR. SIEBER:  So the bottom line is that
           you made out, right?
                       MR. HAEGER:  Right, although -- well, let
           me finish though.  At the time that we had our
           application in, that methodology was being reviewed by
           the NRC staff and had not yet been accepted.
                       CHAIRMAN WALLIS:  But it has now been
                       MR. HAEGER:  It has now been accepted, but
           there are some data that G.E. needs to collect over
           the next couple of years to do some verifications.
                       CHAIRMAN WALLIS:  So is it true then that
           the actual fluence has probably gone up, but the
           calculated fluence has gone down?
                       MR. HAEGER:  That's correct.
                       MR. MOSER:  As you would expect. 
                       MR. HAEGER:  That's correct.  But to put
           the final note on this, currently we are only asking
           the staff to approve our application for one cycle of
           operation with the current PT curves until this issue
           is further wrung out.
                       CHAIRMAN WALLIS:  Will there be some
           future better measurements of fluence that we can rely
           on, rather than just calculation?
                       MR. MOSER:  Actually, when G.E. did their
           methodology, they actually had samples from KKM that
           they had pulled, along with the overall sample program
           for the industry.  
                       The sample population for BWRs isn't quite
           as big as it is for a PWR.  As we go in time and we
           have more capsules that are being pulled, additional
           fluence calculations will be done, and we will make
           sure that the methodology is correct.
                       MR. BOEHNERT:  Do you have samples at the
           Dresden and Quad Cities?
                       MR. MOSER:  We have samples at Dresden and
           Quad Cities, but they are part of the integrated
           surveillance program that the BWRVIP is in the process
           of pursuing.  
                       DR. SIEBER:  And if you had an extended
           life license you would not have enough samples to take
           you to the end, right?
                       MR. MOSER:  Say that again, sir?
                       DR. SIEBER:  If you went for a 60 year
           license term, you wouldn't have enough samples.
                       MR. MOSER:  Well, as an industry, we will
           have enough samples, but if we --
                       DR. SIEBER:  You have to use the new
           dosimetry methods and you will be okay.
                       MR. MOSER:  Yes.
                       DR. FORD:  How much will the flux
                       MR. MOSER:  You know, I had Harmeta look
           into that for me a whole back, and the nice thing
           about Dresden and Quad, because they have got such a
           big vessel -- it is a 251 inch vessel, and my power
           out of the core is so much lower than a BWR-4 or a
           BWR-5, and a BWR-6 of the same size.
                       At this point in life, I am still below 5
           times 10 to the 20th neutrons per centimeters squared
           at the eight-four.  Now, we have the shroud repairs
           already in place, but it is nice when I inspect my
           vertical welds on the shroud.
                       DR. FORD:  How much will be the flux be?
                       DR. SIEBER:  Seventeen percent.
                       MR. MOSER:  It is about 17 percent, but
           that is based on actually being somewhat lower than
           what we had projected with the Southwest Research
                       DR. FORD:  Is it more than 17 percent
           because you are flattening the --
                       MR. MOSER:  It will be somewhat less than
                       DR. SIEBER:  Well, you don't run it at a
           hundred percent all the time either.
                       MR. HAEGER:  Well, I guess the point is
           that we didn't do an apples to apples comparison pre-
           to-post EPU.  We used the new fluence methodology that
           showed the decrease in the overall fluence, and not
           having done that apples to apples comparison, I don't
           think we can tell you.
                       The point is that it appears to have gone
           down from our previous count.
                       CHAIRMAN WALLIS:  And what is the core
           shroud --
                       MR. MOSER:  Actually, we have done Noble
           Chem, and so that projects the inside and the outside
           surface, and we have also done the shroud repair tie
           rods at all four units.
                       And again that takes care of all of the
           horizontal welds.  So the inspection plan would be the
           vertical welds, which we are doing on a good basis.
                       CHAIRMAN WALLIS:  I would guess that at
           the time of license renewal application that all of
           this is going to be revisited?
                       MR. MOSER:  I am sure it will be.
                       MR. HAEGER:  Yes.
                       MR. MOSER:  You know, going on, the other
           areas that I wanted to discuss were related to flow
           induced vibration, and there is two issues; the
           increase in steam flow, and the increase in the dry
           flow.  If you would switch to the next slide.  The
           Dresden-2 --
                       DR. FORD:  Hold on.  How much will the
           delta-P increase -- well, the --
                       MR. MOSER:  I just read that, and I don't
           have that on the tip of my tongue, but we can look
           that up and give it back to you.  It is not a very
           large increase from what I remember.   
                       DR. FORD:  So in the risk assessment, and
           not the PRA type assessment, but the numerical
           assessment, was there taken into account any potential
           cracking of the excess hole covers?
                       MR. MOSER:  You know, for three out of our
           four units, we have actually replaced the access hoe
           cover, and so that risk somewhat goes away.  And then
           we with the Noble Chem application, and the hydrogen
           injection that we are doing, we feel like we have an
           adequate basis for mitigating the shroud excess hole
                       And for the one unit that we haven't
           replaced, we do inspections on a periodic basis per
           the SIL (phonetic) and the VIP, and while we are down
           there looking at the shroud support, we also look at
           the access hole cover.  Did that answer your question?
                       CHAIRMAN WALLIS:  Noble Chem is good.
                       MR. MOSER:  Say that again?
                       CHAIRMAN WALLIS:  Noble Chem is good.
                       MR. MOSER:  Yes, I really like that
           benefit.  Again, for the dry flow, we had the benefit
           at Dresden of actually being the first BWR-3 plant,
           and so it was well instrumented across all the reactor
           or many of the reactor internals component.
                       And that included the jet pump and the
           steam separator.  When they did the power uprate, they
           varied the levels of power, and they did single loop
           and double-loop operations, and then they were able to
           extrapolate that information as we went to power
           uprate conditions.  
                       The analytical result of that work was
           that accept for the eight jet pump sensing lines, I
           really have no material endurance conditions that I am
           worried about for the components that I have analyzed.
                       Now, for the eight jet pump sensing lines,
           we are slightly increasing our RPM pumps leak speed by
           about 25 to 27 RPM.  And we are so close.  One thing
           that is somewhat unique about Dresden and Quad is we
           have six vain and pillar rather than a five vain and
           pillar at Peach Bottom and Limerick.
                       And when you do that, and just have a
           slight increase, you have eight jet pump sensing lines
           that are close to the natural frequency of the vain
           passing frequency.  
                       We had two options.  We could go down
           there and do a ring test on these eight welds, or
           eight jet pump sensing lines.  But the time that it
           took and the benefit of only being able to exclude
           maybe one or two of these, we decided to preemptively
           strike and install the clamp on all HF pump sensing
           lines, and in fact we will be doing that tomorrow at
                       The dryer posed a different problem, and
           that is a steam flow problem, and just last year at
           Quad Cities when we were in our fall outage, we found
           higher than anticipated radiological issues on our
           secondary side.
                       And as a result of that, we immediately
           went into a route cause analysis, and my job was to
           investigate the dryer and the separators and see if
           there was enough degradation that would cause that
           moisture carryover to occur.  
                       We put a camera on every square inch that
           we could get to with either a robot or a sub, and
           after we looked at this, we really had no degradation
           that would explain the moisture carryover.
                       In fact, they were in fairly pristine
           condition.  So in a sense what happened is that we
           focused our route cause -- and if you will move on to
           the next slide, we focused our route cause on the core
           loading and how we operated the core.
                       And we found that there is some
           differentials in pressure as you get hot areas.  And
           the steaming effect -- and this isn't the best
           picture, but essentially it would overcome the dryer
           in a certain location, and the dryer, because it
           didn't have a perforated plate, wasn't able to
           essentially have the flow dissipate across the dryer
           bank to make full utilization of the dryer.
                       So what we did is we used our Moss Landing
           test data that we had when we were originally
           designing these dryers, and we used computational
           fluid dynamics, and came up with a perforated plate,
           and pulled or looked at each one all the way across
                       And what that does is essentially flattens
           out the steam flow across the dryer bank and decrease
           the velocity going through the dryer so that it is
           able to perform its function. 
                       CHAIRMAN WALLIS:  And all of this has
           already been installed?
                       MR. MOSER:  It is being installed as we
           speak.  In fact, I need to go back and see how the
           progress is doing.
                       CHAIRMAN WALLIS:  So we don't know yet if
           it works?
                       MR. MOSER:  We will know in a couple --
           about a week or two.
                       CHAIRMAN WALLIS:  Now, we had the Duane
           Arnold presentation a couple of weeks ago, and they
           talked about the increase in frequency of loading
           vibration in the steam dryer, and that being
           transferred to the brackets on the steam dryer.  How
           are we set for this one?  
                       MR. MOSER:  Actually, again, since we are
           installing the dryer modification, we do stiffen up
           the whole dryer assembly, but the Dresden and Quad
           dryers, because they were somewhat smaller and thicker
           than the models that preceded it, we have a much
           stiffer unit than say a Peach Bottom unit would be.
                       Now, we also -- if you will flip to the
           next slide, we wanted to cover that.  You know, based
           on what we have done with our asset management, we do
           know that flow induced vibration is a concern.
                       And even though we modeled everything with
           a ANSI finite element program, 3-dimensional, and we
           made sure that both the dryer and the modification
           were well below their endurance limits, and there were
           no problems from that aspect, we know that modeling
           isn't always a perfect science.
                       And so what we have done is we have gone
           to the place to say what can we do from an asset
           management strategy, and what are the safety concerns. 
           Can we address this by just going in and doing an
           inspection plan.
                       And one of the things that I want John to
           hold up -- and this isn't quite a BWR-3 unfortunately,
           but if you look at this dryer up here, we anticipate
           that you will get a fairly good sized chunk out of
           that if it actually cracked off.
                       And the places for it to go are really
           down, and so you get on top of the shroud head, and
           you may get down on the annulus, but it is almost
           impossible -- well, it is impossible in our estimation
           to get it into the fuel where you are really going to
           cause some damage.
                       The other thing that G.E. did for us is
           that in the unlikely case that we actually got part of
           the dryer to go out and get out to an MSIV line, they
           looked at what the MSIV closure would be, and came to
           the conclusion that it would not be an issue and that
           we would be able to close our MSIVs.
                       DR. FORD:  The steam dryer support
           bracket, have you had experience with those cracking
           at Dresden or Quad Cities?
                       MR. MOSER:  I have not had any experience
           with that at Dresden or Quad, but we do understand the
           Susquehanna event and we do understand that there is
           an Asian plant that just had an experience with that.
                       DR. FORD:  Because it could potentially
           crack and you would have he whole dryer assemblies.
                       MR. MOSER:  Well, one of the things that
           we do is we inspect those are a very periodic basis,
           and so far we have not had that problem, but we do
           understand that it is a potential issue, and when we
           set this, we will make sure that we don't have the
           rocking concerning that Susquehanna had.  Any other
                       DR. SCHROCK:  You mentioned the Moss
           Landing data.  That is an experiment that was done on
           a partial mock-up?
                       MR. MOSER:  If I remember right, it was a
           full-scale mockup.
                       DR. SCHROCK:  A full-scale?
                       MR. MOSER:  Yes. This was back in time
           where Moss Landing -- 
                       MR. HAEGER:  George is shaking his head
                       DR. SCHROCK:  I didn't think it was.
                       MR. MOSER:  Partial?  Forgive me, partial. 
           Any other questions?  
                       MR. HAEGER:  Do you want to move on?
                       CHAIRMAN WALLIS:  Well, I guess we should
           probably take a break.  I am just thinking that it
           would be more reassuring to me if you had some sort of
           quantitative measure of success here, and you could
           show that on that scale the present system and the EPU
           were fitted somewhere so that we knew where we were,
           in terms of getting to some --
                       MR. MOSER:  On the carry over?
                       CHAIRMAN WALLIS:  Well, you had a
           discussion here about --
                       MR. HAEGER:  I should point out that each
           of the reactor internal components was formally
           evaluated for stresses, and that those were all within
                       CHAIRMAN WALLIS:  And again it would be
           useful if you could show that you have made -- that it
           appears in the previous case there was criteria for
           acceptance, and here is the new case, and here is some
           criteria for acceptance, and see some numbers or
           matrix of comparisons.  
                       It would be a little bit more reassuring
           to me than a discursive presentation.
                       MR. MOSER:  Actually, we have a backup
           slide.  We did testing at the Peerless facility in
           Dallas to make sure that our perforated plate was
           going to work, and if you don't mind putting that up. 
                       It is a two-pronged approach.  We have to
           manage the core correctly, and we can't have a very
           hot spot.
                       MR. HAEGER:  Are you talking about this
           one, Keith?
                       MR. MOSER:  Yes.
                       MR. HAEGER:  I think he is thinking though
           about -- you are thinking about the stresses?
                       CHAIRMAN WALLIS:  Yes.
                       MR. HAEGER:  And that is all in the
           material that we submitted to the NRC.  I guess -- I
           apologize --
                       CHAIRMAN WALLIS:  So we have to ask the
           staff about how they found this material acceptable,
           rather than see the material itself?
                       MR. MOSER:  The actual stress loads on the
           dryer are very, very low from the analytical
           standpoint.  They are well belong 10,000.
                       CHAIRMAN WALLIS:  As long as it doesn't
                       MR. MOSER:  Yes, as long as it doesn't
                       MR. HAEGER:  And just to summarize what
           Keith said, we did the finite element modeling on the
           dryer, and that showed that within limits, and then we
           are following that up with the inspection program.
                       CHAIRMAN WALLIS:  And you are doing that
           because the actual prediction of these vibrations is
           a little bit iffy, and so you have to keep monitoring
           and inspecting.
                       MR. MOSER:  You know, going back to our
           asset management strategy, if there is industry
           experience, we want to keep on top of it, and that is
           why we have the inspection program.
                       CHAIRMAN WALLIS:  I think this might be a
           good time to take a break.  Can we be back by 3:30? 
           We will take a break until 3:30.
                       (Whereupon, at 3:19 p.m., the meeting was
           recessed and resumed at 3:31 p.m.)
                       CHAIRMAN WALLIS:  Back on the record.  
                       MR. CROCKETT:  Good afternoon.  I am
           Harold Crockett, and I am the fact program manager
           with Exelon and Canterra.  I would like to talk about
           our flow accelerated corrosion program this afternoon,
           and from time to time I will change that name to the
           acronym FAC.
                       What have we done to address uprates.  I
           am going to talk a little bit about susceptibility. 
           It is interesting to note that there are no new
           systems susceptible to FAC as a result of the uprate.
                       And I am going to talk about the
           predictive methodology and the CHECWORKS analysis, and
           then we will go into the impact in a following slide,
           and show some of the details of that.  
                       I will discuss our programmatic controls,
           and how our program works, and how do we do these
           things.  And then I will summarize on a conclusion
                       It is useful to start with susceptibility. 
           This is a chemical degradation, and fact effects,
           carbon steel components in a steam cycle, where the
           temperature exceeds 200 degrees fahrenheit  
                       DR. KRESS:  Do you add oxygen into your
                       MR. CROCKETT:  Yes, sir.  Dissolved oxygen
           is typically I think 30 ppb or greater typically. 
           Dresden and Quad Cities use the standardized Exelon
           programs to predict, detect, and monitor for full
           accelerated corrosion.
                       And we use the EPRI guidelines that is
           really the basis for all domestic power plants, the
           ANSAC-202L document, and that is really a living
           document that is revised from time to time, and it has
           caused us to realize other activities at the plant
           that tie into our FAC program, notably our performance
           monitoring leaking valves, and those kinds of things
           that we turn into our program.
                       We go in and examine now some of the
           components, and the feed water heater shells have been
           a big issue in the past several years.  So staying in
           touch as far as the industry has helped us a lot.
                       The code that we use for our predictive
           analysis is the EPRI CHECWORKS code, and that is how
           we evaluated our changes, and that's how we initially
           modeled the plant.  
                       And then in the next slide, I will
           describe the EPU conditions and how they are bounded
           by the CHECWORKS parameter ranges.  This slide
           addresses the changed input for the analysis.  
                       Obviously, there are other inputs -- the
           typing diameter, and piping material, and geometry
           factors, that did not change.  But here are some of
           them that were, and while I was preparing this slide,
           I called up some of my counterparts at the other
           utilities just to get a feel for what kind of values
           they were using in their plants.
                       Are we are hitting new ranges that we have
           not previously seen in the industry, and that was kind
           of my question, and I wanted to find out where they
                       So I am going to talk about four of these
           values right now; the steam rate, or really for the
           sake of this discussion the feed rate, and these
           numbers will vary because obviously you have seen some
           other charts that may talk about valves wide open,
           versus hundred percent power, and 115 percent power,
           and those kinds of issues.
                       But the numbers will be consistent in our
           analysis.  The CHECWORKS program is really geared up
           to have a hundred-million pounds per hour, and
           obviously nobody is at that level.  
                       The pre-uprate, we were at about 9-1/2
           million pounds per hour, and we will be going to a
           little over 11-1/2 million pounds per hour.  Now,
           BWRS, the ones that I talked to were as high at 14
           million pounds per hour, and PWRs almost approaching
           16 million pounds per hour.
                       Now, the velocity, obviously since your
           diameters change throughout the line in going through
           valves and such, and it is calculated in the program,
           and feedwater is pretty significant to people
                       Our old analysis, I think actually this
           philosophy was before the feed pumps, where we found
           22 feet per second.  With the new analysis, and with
           all the pumps going, we actually -- the highest value
           that I found was just over 23 feet per second.
                       And when I was talking to some of the
           other utilities, the numbers that I got feedback on
           were 24 feet per second and higher, and after I made
           up this slide, I talked to one that mentioned 27 feet
           per second, and these are not uprated conditions.
                       And so we are still within those values as
           well.  Steam quality.  We have talked a little bit
           about how we are maintaining the dryness of the steam,
           and the operating temperature, and some slight
           differences there.  
                       We are going in the final feed water from
           340 degrees to 356.  Boiling water reactors we have
           seen 420 degrees, and PWRs, 446 degrees.  And actually
           check codes have been used on fossil plants to
           slightly higher temperatures.
                       So the conclusion is that all of our
           values are really within where the industry is using
           the predictive analysis.
                       DR. SIEBER:  A quick question on steam
           quality, do you have a way to measure it in your
                       MR. HAEGER:  Yes, we will do a carry over
           test with the steam dryers.  At Braidwood, for
           instance, we did it with saviors.
                       DR. SIEBER:  Well, you can't do that with
           BWR.  It gets swamped out.
                       MR. DIETZ:  My name is Jerry Dietz, and I
           put together the start up tests.  We will be measuring
           the carryover with sodium from the reactor.  It is
           trans-sodium that is naturally occurring, and it will
           take a sample in the hotwell and in the bottom of the
           condenser, and we will compare the two, and that ratio
           will give us the carry over.
                       DR. SIEBER:  Do you do that on a regular
           basis or just as a part of the start up?
                       MR. DIETZ:  Well, we have been doing it
           for almost a year now at the plants in regards to our
           modification, and then we will be doing it as we come
           up at each pipe toe in the test, verifying that it is
                       There has been some new industry data,
           too, that there is some assumed values for carryover
           and some plants have much lower, and we are also
           factoring that into our test program.
                       DR. SIEBER:  It seems to me that unless
           you measure them on a periodic basis, degradation of
           the dryer elements would cause additional moisture,
           which accelerates flow, which accelerates corrosion.
                       MR. DIETZ:  It will change with each set
           of rod patterns, and configuration of rods, and Tim
           may be able to tell us more about what Quad does.
                       MR. HANLEY:  Several years ago -- this is
           Tim Hanley again.  Several years ago, we found that we
           had a carryover issue at Quads City, Unit 1, and to
           monitor that and address this, we do on a periodic
           basis take samples in the hotwell and determine our
           carryover fraction.
                       I can't say for sure that they do that at
           Dresden, but I do know that we do that at Quad Cities
           as part of a routine chemistry sample.
                       DR. SIEBER:  And routine is what, monthly
           or something like that?
                       MR. HANLEY:  Yes, I believe it is done on
           a monthly basis.  
                       DR. SIEBER:  Thank you.
                       CHAIRMAN WALLIS:  So your concern is
           corrosion in the steam line; is that what you are
           worried about?
                       DR. SIEBER:  Yes.
                       DR. SIEBER:  It screws up the carbon, too.
                       CHAIRMAN WALLIS:  Yes, but this is a fact
           that they are talking about.  Does CHECWORKS take
           account of flow patterns and two-face flow in the
           steam line?
                       MR. CROCKETT:  In the steam line, the
           industry has regarded that as being so close to dry
           that it is essentially non-susceptible, and we do some
           analysis and testing.  But at large the plants
           consider that to be dry, and not susceptible, the main
           steam line.
                       CHAIRMAN WALLIS:  When do you worry about
           what steam for fact?
                       MR. CROCKETT:  We have seen no indications
           in the industry of wall loss in the main steam lines.
                       CHAIRMAN WALLIS:  So this is a non-issue?
                       MR. CROCKETT:  Yes, that's correct, and as
           long as the steam does not get any worse, we do not
           see this as an issue.
                       MR. HAEGER:  I guess the point is that he
           is asking why the --
                       CHAIRMAN WALLIS:  Well, the 99.8 percent. 
                       MR. HAEGER:  I guess it was just to show
           a representative input to the fact.
                       CHAIRMAN WALLIS:  Maybe we should move on.
                       MR. HAEGER:  Yes, let's go on.
                       DR. FORD:  Could I just check?  All you
           are expecting is a one foot per second increase in the
           feed water line?
                       MR. CROCKETT:  Well, the earlier higher
           velocity was before the feed pumps, and now we have
           three feed pumps going, and this higher velocity
           downstream of that in the final feed water, and so it
           is not that 5 or 6 percent throughout.  It is just the
           way that it unfolded in here.
                       What is the impact on the wear rates, and
           another thing that I would like to bring up at this
           time is that we have been fairly proactive in material
           upgrades, and putting in chrome moly and materials
           that are not susceptible to flow accelerated
           corrosion, and that has given us a stronger position
           at all our plants.
                       And that is consistent with where the
           industry is, and we are trying to be proactive so that
           even the lines that we are doing now and that we are
           looking at, the scope as time goes on, we continue to
           reduce susceptible lines.
                       DR. FORD:  So is that first one a chrome
                       MR. CROCKETT:  No, I am not talking about
           chrome moly in any of this.  This is still facts
           suspectible lines.  Once I make it chrome moly, it is
           not longer susceptible.  
                       In the wear rates, we saw that we had some
           mild increases and some decreases, and when I first
           reviewed the data, the uprate data, I wanted to know
           what systems are doing what.
                       And so feed water obviously is a
           significant consequence, and the worst wear rate, or
           the highest absolute value was this 21 mils per year. 
           There were some lines that had a higher percentage
           increase.  Like the reactor water cleanup was at one
           mil per year, and that had a 33 percent increase, and
           so that was 1.3 mils per year.
                       CHAIRMAN WALLIS:  These feed water line
           wear rates are actually measured as well as
                       MR. CROCKETT:  Yes, sir.  We go out with
           ultrasonic inspection --
                       CHAIRMAN WALLIS:  When you measurement
           something like 19 mil per a year on your --
                       MR. CROCKETT:  That is correct.  That is
                       DR. FORD:  Now, you predict that it is
           going to go to 21 mils per year, and so presumably you
           have got some faith that the CHECWORKS is correct, and
           presumably in your fact management, you compare --
                       MR. CROCKETT:  We always compare measured
           wear with predicted wear, and that allows you to
           refine your predictive analysis.
                       DR. FORD:  And what would you sigma value
           be on that? 
                       MR. CROCKETT:  Well, what the EPRI
           guidelines are for the predictive analysis is to come
           up with a line correction factor that ranges from .5
           to 2.5, and you get a confidence once your comparison
           is predictive to measure comes closely together.
                       If it does not come closely together, then
           you have to do more work, more inspections
                       DR. FORD:  Is that a kind of fudge factor?
                       MR. CROCKETT:  Well, it is a continual
           refinement of comparing it, yes.  The line correction
           factor shows you how close you are.
                       DR. FORD:  What I am trying to get at is
           that you have only got -- you are only predicting a
           two mils per year change.
                       MR. HAEGER:  I think the next slide will
           answer what you are asking.  
                       DR. FORD:  I mean, does this mean
                       MR. CROCKETT:  That's why we don't believe
           it is a significant impact is what you are going to
           see in the conclusions.  
                       MR. HAEGER:  I think the next slide is
           really what he is talking about.
                       MR. CROCKETT:  Okay.  How do we deal with
           these changes?  That's exactly right.  On the lines
           that have increased wear rates, we have brought out
           next scheduled inspection closer.  So if we are
           looking at R-17 right now, we are at our 17, and the
           next scheduled inspection was perhaps R-20, and we may
           have pulled that back to R-19.
                       MR. HAEGER:  Meaning the refueling outage.
                       MR. CROCKETT:  The refueling outage, yes,
           I'm sorry.  And what we have the dash there for, the
           1.1 factor of save, we increase our wear rates by 10
           percent to account for uncertainties, variations, and
           to give us a little more conservatism.
                       And then as I mentioned earlier, we
           reinspect at least one cycle before we anticipate
           hitting the minimum wall thickness.  
                       DR. FORD:  Are you ever go to advance at
           a rate -- well, are you ever going to hit the minimum
           wall thickness?
                       MR. CROCKETT:  Typically, we do not.  Our
           inspection program has been pretty successful.  We
           don't walk on water.  Sometimes things wear slightly
           faster, and that's why we incorporate the factor of
                       DR. SIEBER:  Well, CHECWORKS is really
           intended to tell you where to inspect.
                       MR. CROCKETT:  That's correct.
                       DR. SIEBER:  And the official number that
           you get is the number that comes off of the thickness
           gauge, the UT thickness gauge.
                       MR. CROCKETT:  That's correct, yes, sir. 
           And I would like to emphasize that in this next 
           bullet that we are going to continue to perform
           inspections on susceptible lines, and compare them to
           the predictions, and we are going to continue to
           upgrade material.
                       When we see a line that is wearing, we are
           not going to get their management wear.  It is not
           cost effective to me to keep going out and seeing
           something that is wearing, and uninsulating scrapple
           and then UT it.
                       After we do that several rounds, we are
           going to upgrade it with fact resistant material.  And
           this was your comment earlier, the last bullet, that
           whenever appreciable wall loss occurs, we expand the
           sample, which means that we look upstream and
                       And we look in sister trains and that type
           of thing to make sure that we bounded the conditions
           of the wear.  What we found is that we are bounded by
           industry experience, as well as our predictive codes.
                       The predictive analysis has been revised
           to determine potential impacts, and the inspections
           for the affected components have been accelerated
           where it is appropriate.  Inspection data is
           incorporated into the program and it will continue to
           be incorporated.
                       In conclusion, the uprated conditions do
           not significantly affect flow accelerated corrosion at
           Dresden and Quad Cities.
                       DR. FORD:  I have another question.  If
           you don't have any platinum eroding --
                       MR. CROCKETT:  Platinum in the feed water
                       DR. FORD:  Platinum from Noble Chem.
                       MR. HAEGER:  Can anybody help us with
           that?  Tim, did you hear the question?
                       MR. T. HANLEY:  This is Tim Hanley again.
           The only part of the feed water lines would be up to
           the check valve to the vessel, the last check valve
           that was injected into the reactor water cleanup
           system.  So it would only be that portion up to the
           last check valve.
                       MR. CROCKETT:  Bill Burchill will be next.
                       MR. BURCHILL:  Good afternoon.  My name is
           Bill Burchill.
                       CHAIRMAN WALLIS:  Welcome, Bill.  I have
           to say that you are twice as old as the last time that
           I saw you.
                       MR. BURCHILL:  Well, Grant, you have not
           changed at all.  Graham and I did some great things
           about 25 years ago together, right?  Or was it 30. 
           Gosh, it has been a long time.  
                       My name is Bill Burchill, and I am the
           Director of Risk Management for Exelon, and on my left
           is Larry Lee from Aaron Engineering.  Larry did most
           of the risk evaluations that we are going to be
           talking about today.  So hopefully he will get a
           chance to participate here.
                       On the next slide, I have outlined the
           topics that we are going to cover.  Principally, there
           are two types of risk evaluations that we did; those
           that were quantitative, and both of a full
           quantification of the PRA mode; and also some limited
           individual special effects quantifications, and then
           the qualitative evaluations.  And we will talk about
           both of those.
                       CHAIRMAN WALLIS:  ACRS will tell you that
           there is no such thing as qualitative risk
                       MR. BURCHILL:  Yes, I have talked to
           George about that, and I am fully aware of his
           position.  Thank you though for reminding me.  The
           purpose of this risk evaluation -- and I want to start
           out by saying that we use generally accepted figures
           of merit for risk, which is CDF and LERF.  
                       So those were applied and those are the
           figures of merit that as you know are called out in
           Regulatory Guide 1.174.  We estimated the change in
           both CDF and in LERF using the full power internal
           events model, and that was the only model that we
           actually did a full quantification evaluation.
                       For other risk sources, external events,
           and the shut down state, we did qualitative
           evaluations, although with some numerical evaluation
                       The other important aspect of this was
           that it helped us to identify parts of the PRA that
           would be impacted EPU plant changes, and that will
           guide us then in updates to the PRA that will be used
           to properly represent the as built as operated plant
           when EPU conditions are implemented.
                       A brief outline and the methods.  Of
           course, we had to identify the plant configuration
           changes that were due to EPU, and most of those had
           been outlined already today.
                       We looked at the hardware changes, and the
           procedure changes, operating condition changes, and
           set point changes.  And in each case, we looked at
           what those changes would impact within the PRA
           evaluation models.    
                       We used recently upgraded PRA models for
           both plants.  These are not the models that were used
           for the IPE studies.  They are significantly upgraded
           models, and both upgrades were completed in 1999.
                       And in both plants the upgraded PRAs have
           been reviewed by the BWR owners group certification
           peer review process.  In each case, we identified the
           elements of the PRA that are affected, and I will go
           over those in somewhat more detail in the next slide.
                       The next two bullets will be the
           foundation for why you will see a number of
           differences between the numbers that I will show you,
           and those that you have seen earlier in the afternoon.
                       PRA by its very nature uses realistic
           evaluation techniques.  It compares with realistic
           success criteria, and limits, and therefore some of
           the numbers that I am going to speak to will be
           different from ones that you heard earlier, and if you
           wish, I will go back and explain some of those
                       When we looked at the impact, we used
           sensitivity studies, and we did not do a full update
           of the PRA.  We looked at individual parts of the PRA,
           and we changed those parts as we felt that they were
           appropriate to represent the impact of the EPU
                       And then finally as a benchmark, we
           compared the results to the guidance for risk
           significance given in Reg. Guide 1.174.  As you know,
           this is not a risk informed submitted, but we felt
           that that guidance was a useful comparison for a
                       Now, we reviewed each of the PRA technical
           elements, and in particular we looked at initiating a
           bench, and we looked at whether there were any new
           initiating events, or whether there were any changes
           to existing initiating events in the PRA.
                       We looked at success criteria.  For
           example, changes due to EPU and boil down times, and
           reactor pressure vessel inventory makeup, rates, pool
           heat load, RPV, over pressure protection and
                       Every one of those as you can readily
           imagine mechanistically can impact what the success
           criteria are.  So in each case, we did look at that,
           and either evaluate that it was insignificantly, or if
           we saw that there was a significant impact, actually
           put it in the PRA and see what influence it had.
                       We looked at all of the system changes
           that were made, both hardware and set point, and we
           looked for whether or not those system changes
           produced any new scenarios, and also whether it
           impacted the failure rates that were assumed within
           the PRA.
                       Similarly then we looked at data to see
           whether or not the increased duty on some of the
           equipment would impact some of the PRA reliability
                       Probably the biggest area that was
           identified, and I think you can readily imagine is in
           the operator response area.  There are a large number
           of operator responses in a PRA.  Failures by the
           operator generally contribute to on the order of 30 to
           50 percent of the core damage frequency in a PRA.
                       So it is a very significant contributor. 
           So we evaluated in each case the most significant
           operator actions in the PRAs.  In both cases, that was
           on the order of two dozen actions which had a FSAR
           vastly greater than .005 or a raw greater than one. 
                       Those are the typical values used to
           determine risk significance, or I'm sorry, a raw
           greater than two.  And we also looked at time critical
           operator actions.  
                       But we looked at structural responses,
           which are particularly important of course in
           containment response.  We looked at quantification,
           and in that regard, you look at whether or not the
           risk profile changes, which gives you an indication of
           whether or not there has been anything new introduced.
                       We looked at individual cut sets, and we
           also looked at whether or not our truncation was
           adequate at the uprate conditions.  And then the
           embodiment of all of that shows up in looking at the
           event tree sequences.  
                       We did do a number of additional thermal
           hydraulic calculations, many of them with a map code,
           to evaluate the impact of the changes due to time to
           boil down, and times to core damage.  
                       The next two slides outline in general the
           qualitative impact on the PRA, and I will follow that
           with then an explicit evaluation summary of the
           quantitative impacts.
                       I would like to preface this by saying
           that we didn't find any new accident types, which is
           of course no real surprise, and we found no
           significant changes to the existing accident scenarios
           in the PRA.
                       We found no changes in system
           dependencies, and of course that is a very important
           aspect of plant modeling.  And we found no
           vulnerabilities that were produced by the PRA, or by
           the EPU rather.  
                       We did find limited logic structure
           changes relative to operator actions, and then of
           course changes in the human error probability of some
           of the actions.  
                       Now, the things that we did find under the
           operating condition area was the decreased decay heat
           load reduces times to boil down pool temperature
           limits and times to core damage itself. 
           This obviously puts more limit on --
                       CHAIRMAN WALLIS:  Hold, please.  I am
           trying to figure out the grammar here.  Reduces.  I
           thought that this read that it reduces pool
           temperature limits and reduces core damage, and
           reduces qualifying evidently came after.   
                       MR. BURCHILL:  It reduces the time to,
                       CHAIRMAN WALLIS:  It doesn't reduce time
           to pull temperatures limits, or I guess it does. 
                       MR. BURCHILL:  Times to is qualifying
           everything after it, and the impact there is primarily
           as you can imagine on the operator action times, the
           response times.
                       Now, recognizing that, and the fact also
           is that most of the operator response times of
           interest are in a fairly long time frame, and so you
           are talking mostly response times that are greater
           than 20 or 30 minutes.
                       So the ultimate quantitative impact is
           generally fairly small.  Increased ATWS power levels
           and peak pressures; again, more limiting success
           criteria, and reduced time for operator action.
                       And then again the increased required
           number of feedwater and condensate pumps.  This has
           the potential for increasing the turbine trip
           initiating event frequency, because of the fact that
           with all of the pumps operating, any individual pump
           tripping off may have the potential for producing a
           turbine trip.
                       CHAIRMAN WALLIS:  Increased ATWS power
           levels and peak pressures; isn't that controlled by
           valves opening, and it actually increases the peak
                       MR. HAEGER:  And that is what that second
           bullet is saying; more limiting success criteria for
           ATWS, in terms of the number of valves.
                       CHAIRMAN WALLIS:  Pressure controlled by
           the valves opening?
                       MR. HAEGER:  Yes.  And one of the success
           criteria is how many valves open.
                       CHAIRMAN WALLIS:  I thought the peak
           pressure stayed the same, but more valves had to open
           in order to keep it the same.  And how you are
           actually saying the peak pressure itself does go up?
                       MR. BURCHILL:  In a realistic calculation,
           the peak pressure will go up and you will need more
           valves to stay below the limit.  So both occur.
                       CHAIRMAN WALLIS:  Because of the set
                       MR. BURCHILL:  Right.  Now, on the last
           point that I made here, because this is a fairly
           significant one, this is the only place where we saw
           a potential increase in an initiating event frequency,
           the evaluations that were done were done early before
           a completion of the recirc runback feature that was
           discussed earlier, and so they do not take any credit
           for that recirc runback.
                       We believe that with the recirc runback
           that there would be no increase in initiating event
           frequency, except in the case of a recirc runback
           failure, simply because of the fact that you would not
           have the single pump tripping leading to a turbine
                       And in the next slide, we talk about the
           system effects, and specifically to the point that we
           were just talking about, an over pressure protection.
                       We find that an increased number of
           reactor safety and relief valves is required for over
           pressure protection.  As you know on these plants,
           there are 13 valves available.  The current success
           criteria is 11 valves to hold the pressure.
                       And in the case of the EPU, we found that
           would increase to 12 valves.  The increased number of
           reactor relief valves required for emergency
           depressurization on any of these plants, there are
           five valves, and currently only one valve is required
           for emergency depressurization.
                       Under the EPU conditions, we judge that
           that would go up to two valves.  So this modifies the
           success criteria for transient small and medium LOCAs,
           and again for ATWS.  
                       And we looked a numerous BOP and set point
           changes, as well as logic changes, which produced
           negligible risk, and most all of these changes were
           described by John Nosko at the beginning of this
                 I want to note in particular that the electrical
           load fast transfer that I think was mentioned earlier,
           and talked about by Mr. Sieber, that feature, and the
           addition of the condensate pump trip on LOCA, were
           both found to have a negligible impact.
                       Their impact is conceptually on an
           increased loop frequency, loss of off-site power and
           initiating event frequency.  But when we went through
           the quantification, we found that in fact the increase
           was extremely small compared to the existing loop
           frequency assumed in the model.
                       DR. SIEBER:  I don't know whether you are
           going to get to this later or not, but in the success
           criteria for valves and the way you modeled it, it
           seems that the overriding failure mechanism was common
                       MR. BURCHILL:  True.
                       DR. SIEBER:  And could you explain how you
           treated common cause failures in your analysis?
                       MR. BURCHILL:  Certainly.  You want to go
           through some of the specifics in each case?
                       DR. SIEBER:  Yes.  It doesn't have to be
           real detailed, but I would like to understand it. 
                       MR. LEE:  Okay.  This is Larry Lee from
           Aaron.  So initially the success criteria was one of
           five valves for depressurization.  So it would be a
           common cause of all five valves failing to open.
                       So now that the success criteria is 2 of
           5, you would need common cause failure of any four of
           the valves.  So the common cause failure rate
           increased by approximately a factor of two from around
           1-E minus 4, up to about 2-E minus 4.
                       DR. SIEBER:  And so you came to your
           detailed analysis using beta factors?
                       MR. LEE:  Yes.
                       MR. BURCHILL:  Okay.  The next slide is
           Slide 77, and if we can have that up.  This is the
           slide that we will probably spend most of our time on,
           or at least proportionately on slides, and I will even
           try to time this one.
                       Mention was made earlier that the Dresden
           and Quad plants are similar, but not identical.  And
           this of course is true in the PRA representation. 
           Some of the key features, the Dresden plant has an
           isolation condenser, and it has a dedicated shut down,
           decayed heat removal system.
                       In the Quad plant, we have a dedicated
           high pressure safe shutdown make up pump.  We have no
           isolation condenser.  There are a number of
           differences in the electrical area, and each of those
           are represented in the PRA, and then lead to a
           difference being found in the quantitative importance
           of either those systems or their failure.
                       We looked at about 15 different model
           changes that were quantified with the full PRA
           sensitivity studies, and we looked at a number of
           other model changes, where we looked specifically, for
           example, at just the change in the human error
                       And we found that it was negligible, and
           then did not include that in the full model
           quantification.  This table then in some detail gives
           you the most important ones that we found, in terms of
           carrying through to actually having some significance
           in the eventual impact on CDF.
                       And by significance, we looked at anything
           that was on the order of one percent or more as being
           significant.  And what you will see is that there are
           three groups.
                       One is the impact on the turbine trip
           initiating event frequency, which is on the first
           line, and as I mentioned that is the only initiating
           event frequency that we found impacted.  
                       The next five are in the human error or
           the human operation or action category.  And then the
           last is in the success criteria category, the one that
           we have already talked about with respect to
                       I will briefly speak to each of these, and
           if I am going into too much detail, please don't
           hesitate to stop me.  I am sure that everyone would
           like to get on to something else.
                       In the turbine trip initiating event
           frequency, you will see that there is a range
           represented there for the PRA model change, and the
           size of that range is not indicative of any
           significant difference between the plants.
                       It is indicative of a difference in the
           modeling technique that was used to derive the
           numbers.  In the Quad Cities case, we used a
           simplified fault tree of a fairly conservative nature,
           and that led to the higher number that you see there,
           the 18 percent change.
                       I'm sorry, that was the 2-1/2 percent
           change.  In the Dresden case, we looked at actual
           turbine trip data from a seven year period, and then
           we made an evaluation of whether each one of those
           trips would have actually been aggravated by the EPU,
           or in fact would have occurred under EPU conditions.
                       And so what that led to was the 18 percent
           change that you see.  In quantitative terms, Quad
           Cities initiating event frequency changed from 2 to
           2.05 per year, and Dresden's changed from 1.14 to 1.35
           per year.
                       Now, those changes, when put into the PRA
           model, then lead to the CDF contribution increase of
           the one or less than one to 2-1/2 percent.  
                       Again, I would remind you that if we had
           accounted for the recirc pump run back feature that
           that would essentially be zero.  It would be
                       Each of the five operator actions has to
           do with times being reduced somewhat for the operator
           to take action.  In most cases, we simply scaled these
           times relative to heat load because most of them are
           driven by heat load.
                       The times that we are talking about in
           general are in the 20 to 25 minute range being reduced
           to on the order of 16 to 20 minutes.  So we are
           talking about relatively long action times.  We are
           talking about more or less a 20 percent decrease in
           each case.
                       DR. KRESS:  But what is the time on Item
           4 on that one?
                       MR. LEE:  Line 4?
                       DR. KRESS:  SPC during ATWS.  
                       MR. LEE:  Right.  There are two time
           frames there.  There is an early time frame, and I
           think we talked earlier -- I don't remember if we
           talked the time frame earlier.  On the licensing
           analysis, it is shorter.  
                       But in the PRA analysis, which is a
           realistic analysis, the short time to act is 6
           minutes.  And we looked at the thermal hydraulic basis
           of that and found that that did not change under EPU
           conditions.  For the longer time to act, that went
           from 20 down to 16 minutes.  
                       MR. HAEGER:  That was line 3, I think, and
           so --
                       MR. BURCHILL:  He said line 4, but then he
           said SLCS.  So, I think he was talking about SLCS.
                       DR. KRESS:  It was SLCS that I was talking
                       DR. SIEBER:  Do you have another one that
           was down as long as 10 minutes, I guess.
                       MR. BURCHILL:  Yes, it went from 10 to 8-
           1/2 minutes.  I think it had to do with ADS.
                       DR. SIEBER:  ADS during --
                       MR. BURCHILL:  And what happened was that
           when we evaluated that, that changed and that was well
           less than one percent impact.  That's why you don't
           see it on this chart.
                       DR. SIEBER:  All right.
                       MR. BURCHILL:  Now, one other thing to
           point out, that on the second line there is a range of
           zero to 1.4, and on the fourth through fifth line, it
           is zero to one.  Those zeros are somewhat artificial
           because of the fact that what we found that the actual
           HEP that was in the PRA model in each case was a
           fairly conservative value.
                       So that conservatism in and of itself
           masked any impact.  However, looking at the other PRA
           for a very similar plant, we found more realistic
           values, and we were able to then vary them to give the
           range of influence that you see there.
                       On the last line, the one point that I
           would like to make there, because it is a unique one,
           is that the inadvertent opening of the relief valve,
           or a stuck open relief valve sequences, and the
           increased common cause failure probability that we
           just talked about, is the only place where we actually
           found a modified sequence to occur.
                       If you think about this pre-EPU, we only
           had one valve required for the depressurization, and
           therefore if we had that one valve open through an
           IORV or an SOFV, we would depressurize.
                       With two valves being required for
           depressurization, even though you have one valve
           inadvertently opening or stuck, you still have to
           depressurize.  So there is a new branch that gets
           added to that event tree to accommodate the fact that
           the second valve has to be opened.
                       And Larry has already described the change
           in common cause.  I would also note that you don't see
           on this chart an impact due to the success criteria
           change on the overpressurization.  That was found to
           be very small, well less than one percent.
                       We also looked then at the level two risk. 
           In other words, the containment risk influence.  We
           used a methodology that is described in NEUREG/CR-
                       This is a fairly conservative methodology,
           and it has been reviewed and endorsed by NRC for risk-
           informed submittals.  But it does lead to fairly
           conservative results as we will see in a moment.  
                       There are two groupings of impact that we
           want to consider here.  The first three bullets
           discuss the disposition of the end states from the
           level one analysis.  And that is actually the
           methodology that is described in the NEUREG/CR-6595.
                       It involves a binning technique where a
           binning of the source terms, or fraction of
           radionuclide inventory is used.  That is unaffected by
           the EPU.  The actual release frequency in each bin is
           proportional to the level one result.
                       But the impact of EPU will be specific to
           each bin, depending upon the distribution.  The second
           three bullets are the risk impact on the containment
           response itself.  So there are in fact been
           containment responsive ventries that could attach then
           to the actually end states of each of the level one
           bins if you will.
                       There were very minor changes in the Level
           2 HEPs, and very minor changes in accident progression
           timing, and decay heat load, and a negligible change
           in the timing that we found to containment failure, on
           the order of several minutes over a several hour
                       So what we found then was that the EPU has
           a very minor impact on the Level 2 portion of this
           analysis, but the overall impact on LERF is
           essentially proportional to or similar to Level 1.
                       The quantification results then are given
           in the next slide.  The base PRA results are given in
           the first group there under the first bullet.  Again,
           these plants are similar, but not identical, and for
           the reasons that I cited before, as well as others, we
           do not have identical CDF or LERF based values,
           although I would point out that these are pretty darn
                       CHAIRMAN WALLIS:  Why is LERF so close to
                       MR. BURCHILL:  Because of the conservatism
           in the 6595.  This is about --
                       CHAIRMAN WALLIS:  You might not have the
                       MR. BURCHILL:  You usually expect it to be
           on the order of 10 to 20 percent.  So this is very
           conservative.  To be frank with you, it becomes an
           economic decision.  If we can use it and still meet
           regulatory requirements, we will.
                       And at the time that we find that that
           won't work, we will go to something more extensive. 
           That will probably be during license renewal.  Now,
           the impact of EPU is quite small on both CDF and LERF,
           and in fact if you look at the impact on CDF, for both
           plants, adding up all the little pieces, even though
           there are somewhat differences in the mix, they both
           come out to be an impacted 2.4 times 10 to the minus
           7 per year, which I think you have seen in the
           submittals or in the RAI responses.
                       The difference in percent then is entirely
           due to difference in base value.  It is not a
           difference in the absolute impact.  In the terms of
           LERF, there is a little bit of a difference.  Quad
           Cities has a face value of 1.3 times 10 to the 7th,
           and Dresden is 1.4 times 10 to the 7th.
                       I would note that these results,
           percentage wise, are very similar to what has been
           seen in other evaluations for other plants.  The last
           point is that we did compare these results to the
           guidelines for risk significance in Reg Guide 1.174.
                       Just to refresh, Reg Guide 1.174 for the
           magnitude of CDF and LERF for these plants,
           differentiates between small risk and very small risk
           at 10 to the minus 6th for CDF changes, and 10 to the
           minus 7th for LERF changes.
                       So if you compare what we found on --
           well, I think I said that wrong.  Yes, 10 to the minus
           6 on CDF, and 10 to the minus 7th on LERF.  So the
           change that we found in CDF in both cases is a about
           a quarter of the way up to the threshold between very
           small risk and small.
                       And so we conclude that we are well below
           any concern here, and that the CDF is well within the
           very small risk region.  Relative to LERF, we are just
           barely over the line to small risk, and considering
           the conservatism that we just talked about if we were
           to do that realistically, it seems pretty obvious that
           we would be in the very small risk change arena.
                       An area of considerable concern, and if
           Dr. Apostolakis were here, we would have some
           considerable discussion on are the uncertainties.  We
           looked at the uncertainty and the base full power
           internal events PRAs using standard techniques.  
                       We looked at risk importance measures, and
           we found that the distribution of them and their
           general magnitudes were normal.  We looked at
           sensitivity studies and we looked at the pertinence of
           the various equipment.  
                       We looked at failure rates, and we looked
           at operator actions using ranges of 5 to 10 times the
           human error probabilities, and we compared the results
           to what is reported in NUREG-1150.
                       But we found no uncertainty sources beyond
           those that are identified in NUREG-1150, but we did
           not do an explicit quantitative uncertainty analysis
           of this EPU risk evaluation.  
                       However, if we were to take the
           uncertainty range cited by 1150, which it appears we
           would agree with, the range there is cited to be on
           the order of 5 to 6 times the calculated point value.
                       So if we were to apply that to the delta-
           CDF that we have calculated, we would be just at the
           borderline or slightly above the range, the threshold
           between very small and small risk.  
                       And if we were to apply it to the delta-
           LERF, we would still be within the small risk range,
           even considering the conservatism.  So we think that
           adequately covers the question of uncertainty.
                       Now, we looked at four different areas,
           and qualitatively the present PRA does not explicitly
           include internal flooding in the quantification.  
                       However, in the IPE studies, we did look
           at flooding, and it was found to be a very small risk
           contributor, estimated to be on the order of one
           percent of the base CDF of the plants.
                       Therefore, although the dominant full
           power internal event model changes would apply,
           because they would be applied to such a small fraction
           of the CDF, they are essentially negligible.
                       We found no new initiating events
           increased during initiating event frequencies, and so
           the bottom line conclusion is that the internal flood
           is not impacted by the EPU.
                       Relative to external events, the IPEEE for
           both plants concluded that external events other than
           fire or seismic do not pose any significant risk of
           severe accidents.
                       So what we focused on in this study then
           was the fire and the seismic area.  The fire
           evaluation or both plants used recently revised fire
           PRAs in the 1999 to 2000 time frame, and we completely
           redid the fire PRAs for both plants, and resubmitted
           the associated parts of their IPEEEs. 
                       We did not do a full requantification. 
           Instead, we looked at the dominant scenarios in each
           of these fire PRAs, and qualitatively evaluated
           whether or not they would be impacted by EPU
                       In both cases, we examined the top 10
           scenarios.  In Dresden, the dominance scenario is a
           control room exposure fire, and it contributes about
           40 percent of the fire CDF.  In Quad Cities, the
           control room fire is about 10 percent.
                       Basically, in both cases the control room
           scenarios were evaluated with a very conservative
           conditional core damage probability of about .5, and
           so any impact of EPU would really be subsumed in that,
           and that is not very satisfying.
                       So what we did then was that we looked at
           what were the actual operator actions that that .5
           represents, and we said how much time does he have to
           take those actions.
                       And then again looking at what would be
           the actual impact.  And, for example, if you take
           Dresden, and the time to go out and initiate the
           isolation condenser for a fire scenario, and the
           dominant fire scenario that we are talking about, is
           about 35 minutes.
                       We estimated that would shrink to about
           33, and then the time beyond that to restore makeup to
           the isolation condenser would also change by the type
           of figure that I mentioned previously, the 20 to 16
                       So again a very small impact.  The other
           major type of scenario is decay heat removal scenario,
           and the dominant scenario at Quad is a fire in the
           reactor feed pump area, and that contributes about 25
           percent and leads to a loss of decay heat removal.
                       And that Dresden has about 20 percent of
           its various scenarios tied up in to decay heat removal
           sequences.  Again, the impact on those sequences
           through the human error probabilities is very small,
           because the operator has very long times to respond in
           each one of these cases, on the order of 30 minutes.
                       CHAIRMAN WALLIS:  Are these fire risks 
           -- the CDF contribution is bigger than the full power
           CDF that you were talking about?
                       MR. BURCHILL:  Right.  It is about an
           order of magnitude higher mainly driven --
                       CHAIRMAN WALLIS:  So we were worrying
           about some increases of five percent in something
           which is considerably smaller than this fire risk? 
                       MR. BURCHILL:  Right.  The impact of the
           way that we model fire ignition frequencies, most
           people who do fire PRAs believes is what drives
           results of this type.  This is not an unusual
           comparison between fully quantified fire risk and
           other internal events.
                       So I think it is fair to say that it is
           now a significant debate within the PRA community as
           to how to even compare these two.  In most cases, we
           don't.  We simply address them one at a time, because
           we know that the fire risk evaluation techniques are
           so conservative.
                       Other changes in the success criteria --
           for example, the number of relief valves, has a
           negligible impact, and the ATWS related changes that
           we have talked about would be negligible due to the
           low probability of a fire induced ATWS.
                       We didn't find any new fire initiating
           events or increased fire initiating event frequencies,
           meaning new fire ignition frequencies.  So again we
           felt that the EPU had a negligible impact on fire
                       The seismic area was the third area of
           qualitative evaluation, and we do not have seismic
           PRAs for either one of these plants.  In both cases
           the IPEEE requirements were satisfied using the EPRI
           seismic margin analysis method.  
                       So we looked at those seismic margin
           analyses to determine whether or not there was
           anything in there that would be significantly impacted
           by the increase in power.  
                       We found no impact on the seismic
           qualifications of the structure systems and
           components, and I think that is no surprise.  We did
           look at the potential impact of increased stored
           energy on blow down loads, and we found that that was
           also a very small -- and which as you heard earlier --
           the same conclusion as the deterministic analysis of
           the containment that Mark Kluge described very early
           in the afternoon.
                       We also looked at the impact on ultimate
           heat sink issues, which I think we are going to defer
           and discuss with you in the open issues area.  I will
           just forecast that the result there was determined to
           be minor, but we will describe to you under that
           discussion, which requires really understanding the
                       But we will describe to you how we
           quantitatively evaluated that using a scenario
           specific event tree. 
                       CHAIRMAN WALLIS:  So you are going to come
           back to that?
                       MR. BURCHILL:  We are going to come back
           to that.
                       CHAIRMAN WALLIS:  And the staff has some
           issues with that.
                       MR. BURCHILL:  Right, the staff has some
           issues, and we are going to try to address those under
           our open issues discussion.
                       DR. SIEBER:  I do have one question which
           you can probably answer in one sentence.  I think it
           is Dresden ultimate heat sink operation.  And it talks
           about using the canal to run through the parking lot
                       MR. BURCHILL:  Yes.  
                       DR. SIEBER:  And then having time to
           refill it by pumping into it?
                       MR. BURCHILL:  Yes.
                       DR. SIEBER:  And then the safety
           evaluation talks about portal pumps.  Are those pumps
           at your site at Dresden, and they can be wheeled out
           and operated?
                       MR. KLUGE:  This is Mark Kluge.  Those
           pumps are not on-site, but given the large amount of
           time available to stage those pumps, we have standing
           contracts with pump vendors, and our belief and our
           procedural basis is that we can obtain those pumps in
           ample time to refuel the UHS.
                       MR. BURCHILL:  Not to preempt Mark's later
           presentation, but we are talking about days. 
                       DR. SIEBER:  I'll check that.
                       MR. BURCHILL:  Yes, he will talk about
           that, but we are talking about days, just so we don't
           leave that on the table.  So our conclusion again is
           that EPU has a very minor impact on seismic risk, but
           the particular place where it may have impact is going
           to be described later.  
                       Lastly, in the qualitative area, we did
           look at shutdown risk.  Again, we do not have shutdown
           PRAs for these two plants.  However, it is easy to
           recognize that the dominant full power internal events
           PRA model changes in most cases do not apply, either
           because the times are different or because the
           equipment requirements are different.
                       We did not see any new initiating events
           or increased initiating event frequencies.  It is
           obvious, of course, that the higher decay heat load
           will increase boil down times.  And then we will have
           some minor impact on human error probabilities.
                       Now, recognize that most of the operator
           actions during a shutdown are of a recovery nature. 
           They are recovering, for example, a lost decay heat
           removal system, or something of that type.  And they
           mostly occur in the many minutes to hours time frames.
                       So it is not surprising that there would
           not be much of an impact.  There is one place where
           there is an impact, and that is that there is a number
           of backup systems that are available for decay heat
                       Some of these are low capacity systems,
           and they are not able to be used until the decay heat
           load drops sufficiently so that their heat removal
           capability is sufficient to match decay heat.
                       And so there is a somewhat shortened time
           for that to occur, but again we are talking about
           something out in days, and a shortening of a few days
           on that.  So, a very minor impact there.
                       And the last thing is that we do manage
           our risk during shutdown using configuration risk
           management techniques.  We use a commercial tool
           available that was developed by EPRI called ORAM, and
           I am sure that you have heard of that.
                       It is a defense in depth monitor, and
           there is no impact whatsoever of EPU on the use of
           that tool, and how it would be applied during an
           outage.  So again we conclude that EPU has a
           negligible impact on shutdown risks.  
                       So, I will summarize, and I note, Dr.
           Wallace, that you are getting tired of me saying over
           and over again negligible, small, minor, but that is
           what we found.
                       The risk impact was evaluated using
           standard PRA methods, and with deference to George,
           both quantitative and qualitative.  The quantified
           impact was a small percentage of the current plant
           risk, and it is well within the criteria that the Reg
           Guide 1.174 specifies for either a very small or small
           risk impact.
                       DR. KRESS:  Let me ask you a question
           about that.  
                       MR. BURCHILL:  Yes.
                       DR. KRESS:  I seem to recall in Reg Guide
           1.174 that they had an absolute limit on LERF of 1
           times 10 to the minus 5?
                       MR. BURCHILL:  What you are thinking of is
           in Reg Guide 1.177.  There is an absolute limit of 5
           times 10 to the minus 7th on delta risk, which is
           essentially a CDP, or what is now being called an
           ICCDP, which is a change in risk, multiplied by the
           time over which that risk exists.  I think that is the
           only place that there is an absolute.
                       DR. KRESS:  I thought that the 1.174 was
           divided up into regions.
                       MR. BURCHILL:  Yes, there is.
                       DR. KRESS:  And if you were in a region
           above --
                       MR. BURCHILL:  Oh, that's true.  If your
           base is too high, you're right.
                       DR. KRESS:  Too high, and that value for
           -- well --
                       MR. HAEGER:  If I could reply to that.
                       MR. BURCHILL:  Which one are you putting
                       MR. HAEGER:  The Quad CDF impact.
                       MR. BURCHILL:  Yes, that's fine. If you
           want to turn it on.
                       MR. HAEGER:  Do you want to do LERF or
                       DR. KRESS:  LERF.
                       MR. HAEGER:  You can do it either way.
                       DR. KRESS:  Yes, they are almost the same,
           but we will do the LERF.  Now, the dark region is the
           region where no changes are allowed.
                       MR. HAEGER:  Unacceptable, right.
                       DR. KRESS:  And on that LERF line that is
           like something times 10 to the minus 5 --
                       MR. BURCHILL:  Actually, it is about 10 to
           the minus 4.  This is 10 to the minus 5, and this is
           10 to the minus 6.  And what we found is that we were
           right about here.
                       MR. HAEGER:  Here is where the box is.
                       MR. BURCHILL:  Yes, where the box is, and
           we are about here.  This is where we are, and the 1.37
           times 10 to the minus 7.  And at a base of 4 times 10
           to the minus 6.
                       DR. KRESS:  And if you were to add in the
           low power shutdown, and add in the seismic, and add in
           the fire, would that move you very far in that
                       MR. BURCHILL:  I can give you a judgment
           on that, because we don't have it quantified, but I
           would judge that it would be very small movement in
           this direction.       
                       DR. KRESS:  The other question that I have
           is the LERF value where that line is drawn was derived
           on the basis of the quantitative prompt fatality
           health objective.
                       Now, if you increase the power, it seems
           to me that that line ought to move back the other
           direction, because you are increasing the fission
           product inventory, and if you were to back out the
           same fraction or release value from the prompt
           fatality value that you calculate, then the allowable
           value of that line ought to move back in the other
           direction by at least -- well, it is not linear
           because it has to do with a lot of the iodine.
                       MR. BURCHILL:  The way that these explicit
           boundaries were derived is a mix of philosophy in
           numerics, but there is a relationship that is known,
           and that there is about a 3800 megawatt thermal
           assumption that went into the calculation of trying to
           relate these figures of merit to the public health
                       DR. KRESS:  They use sort of an average
                       MR. BURCHILL:  But they use a very big
                       DR. KRESS:  And your plant is much smaller
           than that big one, and so that --
                       MR. BURCHILL:  A 3800 megawatt thermal.
                       DR. KRESS:  So that would move the line in
           the other direction, and it also uses an average site
           source.  So your site is probably much less populated
           than the average, considering a large LOCA.
                       MR. BURCHILL:  I know that we are at a
           lower power level, but I don't know if we are much
           less populated than what was used there.  But I know
           that in the deliberations that have been going on
           about revisions to Reg Guide 1.174, that has been on
           the key points, is whether or not the 3800 that was
           actually assumed to set these boundaries needs to be
           looked at, in terms of actually making these lines as
           you suggest variable.
                       But if we were to actually take the power
           level that we are talking about, in theory the line
           would actually move to the right.  I wouldn't
           subscribe to that by the way.  I don't think that is
           a proper interpretation of how these were done.
                       DR. KRESS:  I was just trying to figure
           out how close you were actually to that line.
                       MR. BURCHILL:  Well, we know this line
           should not be moving this direction, and I believe
           that if we were able to do an explicit calculation of
           the other risk sources, it obviously wouldn't move
           very far this way.
                       And if I were to actually be doing that,
           I would do an explicit level-2, and this thing would
           drive down here anyway.
                       DR. KRESS:  Okay.
                       MR. BURCHILL:  That is the real key,
           because I have got a factor of -- a minimum of two,
           and probably a 4 or 5 in conservatism in it.
                       CHAIRMAN WALLIS:  Well, your box there is
           for this FPIE risk evaluation?
                       MR. BURCHILL:  Yes, it is.  This is a
           legend box and I don't know why there is two of them. 
           And then this one is the result.
                       MR. LEE:  That is what we say in region-2
           and region-3. 
                       CHAIRMAN WALLIS:  You didn't give us
           numbers for fire related CDF, but the staff has some
           numbers which seem to be pretty high.  I mean, 6 or 7
           times 8 to the minus 5.  
                       MR. BURCHILL:  Correct.
                       CHAIRMAN WALLIS:  And they are much bigger
           numbers than any of these.
                       MR. BURCHILL:  Yes, but that is typical.
                       CHAIRMAN WALLIS:  But if we put down the
           same picture, it would take you over into the greater
                       MR. BURCHILL:  If I were to blindly add
           those numbers, it would do that.  But before I would
           do that, I would go in and I would do a whole lot of
           work on my fire ignition frequencies, and I would do
           comp calculations, and --
                       CHAIRMAN WALLIS:  You would bring that
                       MR. BURCHILL:  I would certainly be able
           to bring them down by on the order of --
                       CHAIRMAN WALLIS:  There seems to be a bit
           of uncertainty about the right number to use for these
           fire related CDFs then.
                       MR. BURCHILL:  I'm sorry?
                       CHAIRMAN WALLIS:  There seems to be a lot
           of uncertainty about what to use for these fire
           related CDFs.
                       MR. BURCHILL:  Well, the fire risk
           analyses were a part of the IPEEE, which as to
           identify vulnerabilities.  I think there is a lot of
           question about using them as numerically comparable to
           internal events.
                       CHAIRMAN WALLIS:  Maybe we will ask the
           staff what they think about that.  Do you know what
           that hurricane like region is over to the left there
           on your picture, the dark blob there?
                       DR. KRESS:  That is the crest mark.
                       MR. HAEGER:  That is actually on the
                       MR. BURCHILL:  So our conclusion is that
           we are well within the acceptable ranges on the 1.174,
           which we have just looked at in anguishing detail, and
           that the impact from external events and shutdown is
           either negligible or minor.
                       So overall, if we had the last slide up,
           but it doesn't matter, we believe that the EPU risk
           impact is acceptable.  I would like to make one
           further comment.  I believe that the staff did an
           extremely thorough evaluation in this case.
                       And particularly recognizing that this is
           not, quote, a risk informed submittal, but the fact
           that we did get asked a large number of questions, and
           they spent some times with us in July as you have
           read, I was actually very impressed with their
                       So I just wanted to put that on the
           record.  I know that is something a licensee normally
           says, but I thought that they did a very good job.
                       CHAIRMAN WALLIS:  They were equally
           impressed with your answers to their inquiries.
                       MR. BURCHILL:  Well, I am pleased to hear
           that.  Okay.  I would now like to introduce Mark Kluge
           now, who will continue with the discussion of open
                       CHAIRMAN WALLIS:  Thank you very much,
                       MR. BURCHILL:  You're welcome.  A pleasure
           to meet with you again.
                       MR. KLUGE:  This is Mark Kluge, and we are
           going to cover four of the open items from the staff's
           safety evaluation.  I will be discussing ECCS net
           positive suction head requirements, and the ultimate
           heat sink that we touched on just a moment ago.
                       Then I will bring John Freeman back up to
           talk about the standby liquid control system, and an
           issue involved with that.  And then finally Tim Hanley
           will discuss the large transient testing that came up
           earlier in the presentation.
                       The pre-EPU basis for both Dresden and
           Quad Cities was that credit for a containment
           overpressure is required for adequate ECCS MPSH. 
           Because that is the case, our procedures, our
           training, are all focused on operator awareness of
           that need, and the proper actions to maintain MPSH.
                       The EPU impacts on this condition are that
           using a limiting analysis with the proper conservative
           assumptions to minimize containment pressure, we have
           an overall need to increase the containment over
           pressure credit for the EPU condition.
                       Dresden and Quad Cities installed larger
           suction strainers as to the rest of the BWR fleet, and
           the staff had some open issues with our methodology in
           calculating the head loss for those suction strainers.
                       DR. SIEBER:  That was independent of --
                       MR. KLUGE:  That was independent of EPU. 
           However, EPU provided us the opportunity to address
           those issues.
                       DR. SIEBER:  If that issue is not
           resolved, I take it that EPU is.  What is the caboose
           behind that train?
                       MR. HAEGER:  Well, we have submitted
           material to the staff now that we believe resolves
           that issue. 
                       DR. SIEBER:  Well, it takes two to resolve
           it; you and them.
                       MR. KLUGE:  But we believe that the
           calculation that we have performed now addresses all
           of the staff issues with the head loss methodology. 
           It does result in an increase in head loss at a given
           ECCS flow.  
                       The overall effect from EPU on the Dresden
           and Quad Cities plants, we have a reduced period of
           pump cavitation int he short term over the existing
           analysis.  That small period of cavitation has been
           previously evaluated and shown to be acceptable based
           on some testing that we did of the ECCS pumps some
           years ago.
                       CHAIRMAN WALLIS:  Do you actually know the
           flow characteristics of the pump when it is
                       MR. KLUGE:  Well, there are a couple of
           points to remember here.  First of all, the ECCS
           analysis has to assume a limiting single failure,
           which means inherently that analysis does not use as
           much flow as does our limiting MPSH analysis.
                       Our worse case here is when all of the
           ECCS pumps are operating, and in fact not only are
           they all operating, but we assume a loop select
           failure such that the LPCI pumps are all pumping out
           the break.
                       CHAIRMAN WALLIS:  But when the pump
           cavitates, what do you do?  Do you put in some reduced
           pumping capacity as a function of lower suction head
           or something, or what?
                       MR. KLUGE:  For the assumptions in the
           ECCS analysis, this cavitation wouldn't occur because
           of the reduced number of pumps available.
                       CHAIRMAN WALLIS:  I am just saying that
           there is a period of pump cavitation?
                       MR. KLUGE:  There is a period of pump
           cavitation if I assume that all the ECCS pumps are
           operating.  That period is limited by operator action
           at 10 minutes into the event, and you --
                       CHAIRMAN WALLIS:  Well, what is the
           consequence of having that cavitation?  You reduce the
           flow or what do you do?
                       DR. SIEBER:  You trip a pump.
                       CHAIRMAN WALLIS:  Do you assume that there
           is no flow or what?
                       MR. KLUGE:  Well, the actual pump
           operating characteristics would be slightly reduced
                       CHAIRMAN WALLIS:  Slightly reduced flow?
                       MR. HAEGER:  From all ECCS pumps running,
           and what Mark is trying to say is that the ECCS
           analysis assumes a single failure, and so the flow
           rates are much less there.  
                       The cavitation won't get you anywhere near
           that low of a flow rate.  So we are bounded by the
           ECCS LOCA analysis.   
                       MR. KLUGE:  And not to berate the point,
           but the ECCF analysis also uses lower flows from the
           available pumps; whereas, we assume full flow capacity
           to do the MPSH analysis.  So there are different
           inherent assumptions in these two analyses
                       MR. PAPPONE:  This is Dan Pappone.  The
           flow that they are talking about, there will be a
           degradation in the flow, but that degradation will not
           go from the actual value down to our analysis value. 
                       The value that we assumed in the analysis
           was below the grated flow value.  So effectively we
           have accounted for it in the analysis.  Another factor
           is that --
                       CHAIRMAN WALLIS:  Well, maybe I should ask
           a simpler question.  Even if you have this pump
           cavitation, you are able to calculate that you have
           enough flow?
                       MR. PAPPONE:  That's right.
                       CHAIRMAN WALLIS:  And this is based on
           some model or some understanding of effective
           cavitation on the pump flow characteristic?
                       MR. PAPPONE:  Right. 
                       MR. KLUGE:  Another factor is the time
           when it occurs, and the time when we would expect this
           cavitation to occur after we have reflooded the vessel
           and terminated the core heat up.
                       So that part happens in the first few
           minutes, and the cavitation is out at -- well, let's
           say when we get past the reflooding in 3 or 4 minutes,
           and the cavitation is out in the 5 minute range, the
           5 or 6 minute range.
                       DR. SIEBER:  Plus, there is an implicit
           assumption that there is no vortexing associated with
           the cavitation; is that correct?
                       MR. KLUGE:  Flow characteristics were
           based on testing that we did some years ago.
                       DR. SIEBER:  Where you actually induced
                       MR. KLUGE:  Where we induced cavitation in
           an ECCS pump identical to those installed in Dresden
           and Quad Cities.  That cavitation was allowed to
           continue for a period of an hour, which is far in
           excess of what we are talking here.
                       DR. SIEBER:  Right.
                       MR. KLUGE:  And when the pumps were
           inspected, the results of that cavitation were that
           the pump operability had not been affected.
                       DR. SIEBER:  Well, the vortexing using
           affects the flow in a major way, and I presume that
           during the test that you also did flow measurements to
           see what the degradation was?
                       MR. KLUGE:  That's correct.
                       DR. SIEBER:  And maybe you could tell us
           the percentage.  Was it 90 percent, or 80 percent, or
                       MR. KLUGE:  Well, I don't have that
           information in front of me, but just to echo what Dan
           said, in every case, even the degraded flow would give
           us much lower than what was required for the accident
                       DR. SIEBER:  All right.  Okay.
                       MR. KLUGE:  Moving on to the long term
           reduced pump flow and the long term compared to the
           previous licensing basis analysis, that is partly a
           factor of the increase during our head loss, and
           partly a factor of the increased suppression pool
                       But again all flow requirements, both for
           core cooling and containment cooling, continue to be
           met.  The next two slides show graphically the
           available over-pressure above that which is credited
           in the analysis.
                       If you compare Dresden and Quad Cities,
           there are some minor differences due to plant
           specifics, such as different heat exchanger capacity
           and piping configuration.
                       CHAIRMAN WALLIS:  Now, what does credited
           in the analysis mean?  Is it what the NRC allows you
           to us?
                       MR. HAEGER:  Yes.
                       MR. KLUGE:  Yes, what we have requested.
                       CHAIRMAN WALLIS:  Oh, so you have
           requested something less than what you think is
                       MR. KLUGE:  That's correct.  And all this
           information has been submitted to the staff.
                       CHAIRMAN WALLIS:  When you say credited,
           you mean that is what you need really isn't it? 
                       MR. KLUGE:  That is what will appear in
           our operating license.
                       CHAIRMAN WALLIS:  That is what you need
           and so you are claiming you have got more available
           than what you need?
                       MR. KLUGE:  Yes.
                       MR. HAEGER:  That's correct.
                       DR. SIEBER:  It's always a good idea.
                       CHAIRMAN WALLIS:  And this available is
           calculated with some sort of conservatism which goes
           the other way from when you are trying to calculate
           the loads on the containment when you are conservative
           in the other direction?
                       MR. HAEGER:  That's correct.  There is a
           number of different assumptions made that limit the
           containment pressure that is available.
                       MR. KLUGE:  For instance, the containment
           sprays are assumed to operate since they bring the
           pressure down.  However, the assumed containment heat
           removal capability is the minimum, which of course
           drives the suppression cool temperature up.
                       Moving on to the summary slide, we used
           acceptable methods to determine the suction strainer
           head loss and the NPSH requirements.  Although we do
           experience short term pump cavitation, we devaluated
           that condition and it has no detrimental effect on
           pump operability or meeting the required flow.  
                       And the long term flow rates are
           acceptable, and the operators are aware of the need to
           maintain MPSH per their emergency operating
           procedures.  Therefore, we conclude that the ECCS pump
           and NPSH remains acceptable under EPU conditions.
                       CHAIRMAN WALLIS:  Does the staff agree
           with that?
                       MR. KLUGE:  They haven't indicated to the
           contrary.  We do think we have addressed all of the
           issues with the methodology that we considered.
                       CHAIRMAN WALLIS:  So they have not come
           back to you and said yea or nay yet?
                       MR. KLUGE:  That's correct. 
                       MR. HAEGER:  They have not formally
           replied to us.
                       MR. KLUGE:  Next, I would like to discuss
           the Dresden ultimate heat sink and I will ask Larry
           Lee to come back up here to handle the risk portion.
                       As was previously mentioned, the Dresden
           ultimate heat sink consists of the intake and
           discharge canals to the plant.  And there is a picture
           being put up so we can see what we are talking about.
                       Dresden 2 and 3 intake valve spans from
           this point to this point, and the discharge runs from
           this point to this point.  To give you some idea of
           the scale from the plant to the south end of the lake
           is approximately 3 miles.
                       So we are talking 2,000 foot canals and a
           total inventory that we are looking at in those canals
           once we postulate that the river level has dropped to
           a point, the separation is about 6 million gallons.
                       The ultimate heat sink inventory is used
           both as makeup to the isolation condensers to maintain
           safe shutdown, and for diesel generator cooling water. 
           As indicated before, the canals are then replenished
           by means of portable pumps to ensure long term safe
           shutdown, and those actions are all in the current
                       CHAIRMAN WALLIS:  So whatever it was that
           caused the dam to fail didn't also inhibit the arrival
           of portable pumps?
                       MR. KLUGE:  That is the assumption in the
           current licensing basis.
                       CHAIRMAN WALLIS:  Well, why should that
           be?  I mean, something big enough to fail the dam
           might --  
                       MR. KLUGE:  Well, it certainly could have
           been a localized effect, such as a river barge,
           causing enough damage.
                       CHAIRMAN WALLIS:  Or it could be a seismic
           event or something?
                       MR. KLUGE:  It could be a seismic event.
                       DR. SIEBER:  Well, a lot of plants use
           fire trucks to do that, and they run around to all the
           local fire companies and say if we have this problem
           will you support us.  
                       And I know of a number of plants that have
           made that arrangement.  So it is not impossible to get
           pumping capacity.  
                       MR. KLUGE:  That is correct, and as I
           indicated previously, we do have standing contracts
           with pump vendors to ensure their availability.
                       CHAIRMAN WALLIS:  So portable pumps, or
           something like a fire truck driving up and hitching up
           as a source of water?
                       MR. KLUGE:  Well, the source of water in
           this case is the lowered river bed.
                       DR. SIEBER:  Right.  Is it about a half-a-
           mile from the river to the plant?
                       MR. KLUGE:  Yes, but the required distance
           to pump this water is simply over the contour in the
           canal that has caused the separation.
                       MR. T. HANLEY:  This is Tim Hanley again. 
           We actually had our ice melt line fail at Quad Cities,
           and not this winter, but a winter ago when we had a
           fire truck actually perform this same type of thing to
           keep our intake structure from freezing over.
                       And we had that well within a shift, and
           then portable irrigation pumps also to back that up. 
           So especially in rural Illinois, there are plenty of
           irrigation pumps available if you should need that. 
                       MR. KLUGE:  And to evaluate the impact of
           EPU on the ultimate heat sink, we did a bounding
           analysis, which actually credited the inventory only
           in the intake canal.  
                       And we determined that the available time
           for replenishing the canal would decrease from 5-1/2
           days to 4 days, which we would still consider an ample
           time frame to restore make up means from the lowered
           river bed.
                       DR. SIEBER:  Would you use water from the
           discharge canal?  It seems to me that it was pretty
           hot, and there is always vapor coming off of there.
                       MR. KLUGE:  The assumption in this
           particular analysis was not that we use water from the
           discharge canal.  However, that heat would only make
           a significant difference if we were using the water as
           a cooling source via heat exchangers.  We are just
           pumping it into the isolation condenser and boiling it
                       DR. SIEBER:  Okay.
                       CHAIRMAN WALLIS:  Did you worried about
           net positive suction heads for the fire truck pumps
           and pumping hot water?
                       DR. SIEBER:  They are pumping out of the
           river.  So the river probably never gets about 90
                       MR. KLUGE:  That's correct.  I would like
           to describe the operational scenario here in a little
           more detail.  The initial makeup to the isolation
           condenser is from on-site tanks and the capacity in
           those tanks is considerably beyond what we require in
           the scenario.
                       An operator action is required to reflood
           a bay in the crib house, which due to the lower level
           has lost suction.  And that action is taken by
           installing stop logs and using permanently installed
           pumps to reflood the bay.
                       Then that reflooded bay becomes the
           suction source to the diesel driven fire pump, which
           provides long term makeup to the isolation condenser. 
                       I mentioned that the USH also supplies the
           diesel generator cooling water pumps.  Those pumps
           happen to be at a higher suction level than those that
           reflood the intake bay.  
                       Therefore, if diesel operation is
           required, they become limiting as far as the useable
           inventory in the bay, and they were accounted for in
           the limiting analysis that I described previously.  
                       The diesel generator water cooling water
           flow path is from the intake canal, and through heat
           exchangers, and back to the discharge canal.  
                       The procedures then direct the operator to
           establish recirculation of that water back to the
           intake, which maximizes the use of the available
           water, although again we did not credit the inventory
           in the discharge canal in the limiting analysis.  We
           do credit the recirculation path.
                       The lack of a seismically qualified make
           up path to the isolation condensers was identified
           during our seismic margins analysis.  The original
           FSAR analysis that was the basis for licensing Dresden
           relied on non-seismic equipment, but recognized that
           there was a diversity of make up sources available.
                       However, as a result of the seismic
           margins analysis, we identified the need for a
           modification to provide that seismic makeup path, and
           that is scheduled to go into the plant in 2003. 
                       The staff requested that we evaluate the
           risk of operating with the current configuration and
           in doing that we concluded that EPU had an
           insignificant impact on the plant risk for the
           scenario, and Larry will talk about that a little
                       The seismic margin success path must also
           be able to mitigate a case where a seismically induced
           equivalent one-inch LOCA comes about.  We analyzed the
           situation, and determined that the isolation condenser
           and the available ECCS would mitigate the scenario for
           at least 24 hours.
                       In order to provide a long term
           capability, we identified another modification that
           was necessary, and this would use different portable
           pumps to make up directly to the containment cooling
           heat exchangers, and therefore allow us to maintain
           safe shutdown for a longer time period.
                       All the necessary actions to accomplish
           this will be put into the plant procedures, similar to
           the current required actions.  Again, the staff
           requested that we analyze the risk for the small LOCA
           scenario, and we concluded again that EPU had a very
           negligible impact on this risk.
                       And now Larry will describe those focused
           risk assessments in some detail.
                       MR. LEE:  Hi.  This is Larry Lee.  So,
           consistent with NEUREG or the guidelines provided in
           NEUREG-CR 2300, we used standard seismic risk
           techniques to estimate the risk for specific scenarios
           involving seismic dam failure with failure to the IC
           makeup path.
                       And I will speak to a few of the sub-
           bullets.  First of all, the Dresden site-specific
           seismic hazard curve was used from NEUREG-1488, and
           the information here is based on the studies performed
           by Livermore National Labs, and the curves are judged
           to be conservative.
                       In terms of the -- we evaluated the entire
           seismic hazard curve by dividing the curve into
           discreet .1g intervals so that we could evaluate the
           frequency and the seismic impact for each of the
           intervals, and then add the risk for each individual
           to come up with a total risk for the specific
                       And then the second to the last sub-bullet
           is talking about we calculated the human error
           probabilities for the pre-and-the-post EPU associated
           with the scenarios consistent with how the human error
           probabilities were calculated, and the base Dresden
           PRA model.
                       And we only credited proceduralized makeup
           paths.  So we didn't credit any non-proceduralized
           actions associated with any proposed modifications.
                       In terms of the results, we analyzed two
           cases.  The first one is safe shutdown with the IC for
           a non-LOCA case, and we found that the delta-CDF
           associated with EPU was on the order of 1E-minus 8,
           and for a seismic dam failure with a coincidence small
           LOCA, the delta-CDF was negligible.
                       DR. KRESS:  Did you do an actual CDF?
                       MR. LEE:  In terms of the actual CDF for
           the pre-EPU, and for the first bullet, for the safe
           shutdown with the IC, the CDF was approximately 9.3E-
           minus 6.  So with the delta of 1E-minus 8, the post-
           EPU CDF was approximately negligible.
                       CHAIRMAN WALLIS:  Within the --
                       MR. LEE:  Yes.  For the coincidence small
           LOCA case, the pre-EPU CDF was approximately 1.9E-
           minus 6 per year, and the probabilities for a seismic
           induced small LOCA were based on the Zion analysis
           from NEUREG-4550. 
                       MR. KLUGE:  This is Mark Kluge again.  In
           summary, we have concluded that EPU has minimal impact
           on the ultimate heat sink capability for Dresden.  
                       We will be completing the required
           modifications on the previously committed schedule for
           the seismic margins, IPEEE outlines, and the risk
           impact and increase in risk is very small for these
                       Therefore, the ultimate heat sink is
           acceptable for EPU operation.  If there are no further
           questions, I will ask John Freeman to come back up to
           discuss the standby liquid control system.  
                       CHAIRMAN WALLIS:  Thank you.
                       MR. FREEMAN:  This is John Freeman.  We
           are going to be talking from page 101.  The issue
           involved here was the information notice that was sent
           out a few months ago concerning the standby liquid
           control relief valve margin response under an ATWS
                       Exelon has looked at the standby liquid
           control system for Dresden Unit 2, and concluded that
           there would be no interruption of the standby liquid
           control flow rate delivered to the reactor under the
           analyzed scenario.
                       However, Unit 3 of Dresden and Quad Cities
           1 and 2 are still being evaluated, and there is a high
           potential that we are going to need to make
           modifications to the SLCS relief valves set point in
           order to ensure that that valve will not lift and that
           it will get our ATWS rule required flow rate to the
                       Therefore, the conclusion is that the
           standby liquid control is acceptable at EPU conditions
           for Dresden Unit 2, and it will be acceptable for Unit
           3 of Dresden, and Quad Cities 1 and 2, with the
           completion of the modifications we have planned.
                       DR. SIEBER:  It would seem to me though
           that whether you add EPU or not, that would still be
           an issue.
                       MR. FREEMAN:  That is correct.
                       MR. HAEGER:  Yes, this is not specifically
           an EPU issue.  This same phenomenon would occur prior
           to EPU.
                       MR. HAEGER:  Right. 
                       DR. SIEBER:  Okay.   
                       MR. FREEMAN:  Okay.  If there aren't any
           other questions, I will introduce Tim Hanley
                       MR. T. HANLEY:  This is Tim Hanley again
           from Exelon.  The topic that I am going to discuss is
           the large transient tests.  As you are all aware,
           ELTR-1 specifies two large plant transient tests to be
                       One is an MSIV closure if the power uprate
           goes to 110 percent; and the other one is a generator
           load reject if the power uprate is greater than 115
                       Earlier, a question was asked, well, what
           was the basis, a simple one or two sentence, for not
           doing these tests.  And to begin with, we believe that
           it is unnecessary to assure the plant's response, and
           I will go over some of the reasons why we believe that
           is unnecessary to put the plant through the transient.
                       In both of these scenarios, both the MSIV
           closure and the generator load reject, the SCRAM is
           initiated off an anticipatory signal.  In the case of
           the MSIV closure, when the valves are less than 90
           percent full open, the SCRAM signal is initiated
           inserting the rods, and essentially terminating the
           power excursion.
                       And the generator load reject, as the EHC
           pressure drops and the turbine control valve bodies to
           a certain point, indicating the fact acting solenoids
           have actuated that SCRAMs the reactor and terminates
           the power excursion.  
                       In both tests, feedwater is still
           available for level control and in the case of the
           generator load reject, the bypass valves are still
           available for pressure control.  
                       Most of the major parameters of interest
           in the input into determining how the plant is going
           to respond are unchanged for EPU.  The SCRAM times are
           not being changed, and the valve closure times are
           being changed.        
                       The only thing that has really changed is
           the peak dome pressure, which is really essential in
           both of these.  The beginning dome pressure is not
           being changed.  The only two parameters that are
           changing are the reactor power level and the steam
           line flow.
                       DR. SIEBER:  And the stored energy.
                       MR. T. HANLEY:  Right.  You do have
           additional stored energy.  However, that decays very
           rapidly as soon as the SCRAM goes in.  In both cases,
           you are well within your relief valve capacity are in
           one case within the bypass valve capacity.
                       So the real test and the real parameters
           of concern in these tests is what is your peak
           pressure that you reach, and what is the peak power
           that you reach prior to it turning around prior to the
           SCRAM being effective, and terminating the excursion.
                       When G.E. originally put these in the
           ELTR, they had no experience really with uprating
           plants, and they had no basis for assuming that the
           ODYN code that they used to determine the plant
           response would be effective for uprated conditions.
                       And since that time, G.E. has concluded
           that these tests should no longer be required for
           power uprates at a constant pressure up to a certain
           level, and I believe it is 120 percent, which we are
           not exceeding.
                       CHAIRMAN WALLIS:  Where would this large
           transient test -- you mean that you actually take the
           system to 115 power?
                       MR. T. HANLEY:  No, no, no.  If your power
           uprate goes to 115 percent of your current power
                       DR. SIEBER:  These sub-bullets are
                       CHAIRMAN WALLIS:  They are misleading,
                       MR. HAEGER:  Yes, that is misleading.  
                       CHAIRMAN WALLIS:  Then you have to test
           the ability of the generator to reject load or
           something, but you don't -- okay.  
                       MR. PAPPONE:  This is Dan Pappone.  The
           tests that we are talking about would be performed at
           the uprated power level.  
                       MR. CROCKETT:  That's correct, but not 115
           percent of the uprated power level.  If your power
           uprate exceeds 115 percent of your original license
           power level, then it calls for that.  
                       MR. FREEMAN:  The original intent was to
           perform those tests at the full uprated power level. 
           The safety analysis that has been done at both Dresden
           and Quad Cities has been done using the ODYN code. It
           has been benchmarked against BWR test data, and has
           incorporated industry experience.  
                       MR. BOEHNERT:  What BWR test data?
                       MR. FREEMAN:  Particularly it has been
           benchmarked at --
                       MR. HAEGER:  It is Peach Bottom, right?
                       MR. ANDERSEN:  This is Jens Andersen.  The
           ODYN code has been benchmarked against full-scale
           plant testing, particularly the Peach Bottom turbine
                       MR. BOEHNERT:  Were those at uprated
                       MR. ANDERSEN:  No.
                       MR. BOEHNERT:  So what do you have a
           benchmark at uprated conditions?  
                       MR. ANDERSON:  There are start up tests
           for other plants that have been performed.  
                       MR. T. HANLEY:  In fact, we do have a back
           up of a comparison, I believe, KKM.
                       MR. HAEGER:  Well, what some foreign
           plants have done is do this testing at higher power
           levels than Dresden and Quad.
                       MR. BOEHNERT:  At 120 percent?  At 115? 
           At 110?
                       MR. HAEGER:  Well, it is the thermal power
           that they are at, which is higher than Dresden or
                       MR. BOEHNERT:  So they had a test where
           they had done it 120 percent of uprated conditions?
                       MR. HAEGER:  I think the one set of data
           that we have was 110 percent of their original license
           power.  But I guess the point that we are making is
           that the power levels at Dresden and Quad are at are
           lower than the power levels of these units.
                       MR. T. HANLEY:  And the beginning dome
           pressures are lower than the pressures of these other
           units, and so we are within the bounds of where ODYN
           has been proven to be effective in determining how the
           plant's response will be.
           We are not extrapolating it out to some place where it
           hasn't been proven.  
                       MR. BOEHNERT:  Do we know how applicable
           that plant is to Dresden and Quad Cities?
                       MR. T. HANLEY:  Well, I guess the next
           bullet on the slide is that ODYN uses plant specific
           inputs, models of steam lines and geometries of the
                       DR. KRESS:  Are the valves the same at
           these plants, the same kinds of valves that you have
           to open and close?
                       MR. T. HANLEY:  That I can't say for sure. 
           However, once you isolate the vessel, you essentially
           have relief valves left as your pressure protection. 
           We do know in fact the opening times of our relief
           valves, and those are included in there, which would
           be included at the other plants in their data.
                       And whether they are exactly the same or
           not, that is a specific input that is used in the
                       DR. KRESS:  Oh, that's part of the
           modeling?  That's not in ODYN.
                       MR. HAEGER:  Valve closure times are
                       DR. KRESS:  Valve closure times are
                       MR. HAEGER:  Yes.
                       DR. KRESS:  But whether the valves can
           actually close during time is another issue.
                       MR. HAEGER:  Yes.  We will get to that in
           the next slide.       
                       DR. KRESS:  Okay.
                       DR. SIEBER:  But if you run the test, you
           are going to get all those relief valves and safety
           valve actuations at least for relief valves, right?
                       MR. T. HANLEY:  We will get relief valve
           actuations on the MSIV closure for sure.  You should
           not get any safety valve actuations, but we will get
           relief valve.
                       The power uprate, since the ELTRs were
           initially -- was initially approved, they do have
           additional operating experience to compare the
           predicted plant response to actual plant response.
                       And what it has shown is that the code
           adequately predicts the way the plants would respond
           under those real conditions.  So of those have been
           under plant test conditions, and some have been under
           unplanned transients, where they have gone back and
           collected the data, and compared them.
                       And it does show that the code to
           acceptably predict and also bounding predictions,
           particularly on peak power and peak pressure.  And
           Dresden and Quad Cities both have adequate collection
                       And should we have one of these unplanned
           transients, we would of course go back and verify that
           the code predictions were as we expected.  We have
           done extensive code analysis and the --
                       CHAIRMAN WALLIS:  You might have an
           unintentional test anyway.
                       MR. T. HANLEY:  And we have.  In fact, at
           Quad Cities in the last two years, we have had a
           generator load reject and an MSIV closure at full
                       CHAIRMAN WALLIS:  And you have already
           done the tests?
                       MR. T. HANLEY:  Not at our uprated
           conditions.  Both Exelon and G.E. have analyzed the
           major components that affect the large transients, and
           those are MSIVs, steam piping, SCRAM signal, safety
           release valves, and turbine valves, and the
           interaction of those.
                       We have years of operational experience --
           unfortunately, some of them awfully recently -- to
           show that those components do operate as they are
           designed, and we are well aware of their operational
           history.  And the transient testing does not mean that
           these components will respond as designed.
                       MR. HAEGER:  Now, that was to your point,
           Mr. Kress, that to look at each of these components,
           and really there is nothing in the EPU that would
           change their response to the timing or whatever the
           particular feature is.
                       MR. T. HANLEY:  And in each of them we do
           specific component testing on.  We do stroke our
           relief valves during start up, although some plants
           have gotten away doing that due to the relief valves
                       But in the MSIVs, we do time their closure
           and set their closure time based on to be within our
           tech spec limits.
                       DR. SIEBER:  And do issues like Stone and
           Webster speak to main steam line piping analysis and
           supports, and those are factors here that may be
           different than they were at your previous rating?
                       MR. T. HANLEY:  Those could potentially be
           impacted, because you are interrupting a higher flow.
                       DR. SIEBER:  You have a big hammer, and it
           breaks snubbers and pull things out of the wall, and
           all kinds of stuff.
                       MR. T. HANLEY: The other thing to keep in
           mind though is that we would be running these tests on
           the plants at that power level.  So whether you do it
           planned or it happens sometimes unplanned, the results
           are going to be the same.
                       So from an operational perspective, why
           would I induce this transient on the plant unless I
           had some real concern about the ability of the
           analysis to accurately predict how the plant would
                       If I break a snubber under a planned -- we
           would call it a test, but it is a transient that I am
           inducing, or if I break a snubber when the turbine
           trips from full power at some other time, the effects
           to the operations in the plant are exactly the same.
                       You still have to deal with a broken
           snubber, and so that is really kind of my conclusion
           in all of this, is that we have limited changes to the
           inputs to the plant because we are doing a power
           uprated constant steam dome pressure.
                       Most of the other parameters of interest,
           with the exception of reactor power and main steam
           line flow, are remaining the same.  So these are in
           fact -- although they are labeled as tests, they are
           transients being induced on the plant.
                       And are challenging the equipment of the
           plant, and without a compelling reason, it doesn't
           seem to me operationally to be prudent to go and shut
           all the MSIVs at full power unless there was some
           concern that we didn't have high confidence in the
                       MR. BOEHNERT:  Well, G.E. must have been
           concerned.  I mean, they initially said you should do
           this testing.  What changed their mind?
                       MR. HAEGER:  Well, like I said, they have
           had experience now with some uprates, and it showed
           them that everything works out as predicted.
                       MR. T. HANLEY:  Well, I should ask G.E. to
           respond, but my discussions with them are that in fact
           they have submitted a constant power uprate submitted
           to the NRC that would no longer require these tests.
                       And we can't use that as a basis
           obviously, because it is not approved, but they have
           themselves come to that conclusion, and it is based on
           their experience that their modeling has accurately
           and adequately predicted the plant's response under
           uprated conditions.
                       CHAIRMAN WALLIS:  So their argument is
           that they have already got experience, and there is no
           extrapolation beyond experience involved.
                       MR. T. HANLEY:  That's correct, and in
           fact, Quad Cities and Dresden will be at a lower power
           and lower steam line flow rate than a lot of plants
           were originally licensed to have.
                       Van Gulf, which I have some experience
           with from people that I work with, is over 3,000
           megawatts thermal, with a corresponding steam flow
           rate.  So we are within the bounds where this code has
           been proven to be effective in predicting the plant's
                       CHAIRMAN WALLIS:  This is again where some
           kind of matrix or something would help, and if you
           could show that here is the experience base, and here
           is where you are going to be with the uprate, and just
           as a comparison.
                       MR. HAEGER:  For instance, in the material
           that we have supplied to the staff, we do show some
           specific data from KLL, and I have it here.  KKL is at
           3130 megawatts thermal, and they were -- and that was
           113 percent of their original license thermal power.
                       MR. BOEHNERT:  Has the staff accepted your
                       MR. HAEGER:  That is another open issue.
                       MR. BOEHNERT:  That is an open issue?
                       MR. T. HANLEY:  That's correct.
                       CHAIRMAN WALLIS:  So may be they will
           provide this matrix, or whatever it is, and that we
           can actually look at and see the comparison between
           experience and uprated power in these particular
           plants, and see if it is covered.
                       DR. SIEBER:  Well, I am not sure that you
           can leap right away to the fact that everything is
           okay just by saying that some bigger plant did it
           before me.  I think that it takes more thought than
                       MR. T. HANLEY:  But I think that is part
           of the consideration.  I certainly would be more
           concerned had we been uprating to a new higher power
           level that no plant had ever been licensed to.  So
           that is one of the considerations to look at.
                       DR. SIEBER:  Well, I think more in terms
           of power density, and cubic feet of plant per
           megawatts, and --
                       MR. HAEGER:  Well, once again this power
           density for our plants is lower than other plants that
           are licensed currently. 
                       DR. SIEBER:  I understand.  Okay.
                       MR. T. HANLEY:  So my final conclusion is
           that we shouldn't intentionally put the plant through
           what is a significant transient unless there is really
           a compelling reason, which we haven't found there to
           be one.  Any other questions?
                       CHAIRMAN WALLIS:  And this gets us to the
           end of your presentation?
                       MR. T. HANLEY:  Yes, it does.  It gets me
           actually to the beginning of my next presentation,
           which is the implementation, training, and testing.  
                       I am going to go quickly what training we
           have done for the operators, both classroom and
           simulator training, and what testing we will be doing
           during the start up.
                       When I talk about the testing, it has been
           completed at Dresden, which is going through their
           uprate outage right now.  With the exception that they
           are going to have two hours of delta training that
           they will do just prior to uprate just to get the
           operators reacquainted with the changes, and what they
           will be doing differently when they go about their
           current hundred percent thermal power.
                       At Quad Cities, we have only begun this,
           and we will complete all of the training before our
           February outage on Unit 2, which is our uprate outage.
                       DR. SIEBER:  Will all of the MODS be
           modeled into your simulator?
                       MR. T. HANLEY:  Yes.  In fact, they were
           modeled in the Dresden simulator prior to their last
           session of simulator training, which was all focused
           on EPU, and the same would be true for Quad Cities.
                       Classroom training covered really
           everything that we would normally cover going into an
           outage; any tech specs or other changes; design
           changes, whether they were for EPU or not.
                       We are going to or are covering operating
           procedure revisions that are going in, and mostly
           those are due to modifications.  There are some in
           general that are just due to EPU.
                       Some other things that we did is look at
           the plant limits and operating condition changes, and
           those things include running all the four condensate
           pumps, and all three feed pumps, changes in the
           operation of the pressure control system for the
           turbine throttle.
                       The vessel looked at MELLLA, and the new
           power to flow map, and the differences that you may
           see during certain transients, such as recirc runback,
           and recirc pump trip.  And we did cover some operating
           experience from other plants that have done uprates.
                       Monticello had some feed flow inaccuracies
           that they had not considered when they did uprates,
           and Peach Bottom found that they had excessive
           vibrations and had to put in another coronary EHC
           system, residence compensator.  
                       And in fact that got factored in as a
           modification that we did at Quad Cities and Dresden. 
           Fitzpatrick had excessive vibrations that affected the
           feedwater heating system, and the air line supplying
           those control valves.  So we went over a number of
           things that had happened at other plants. 
                       DR. SIEBER:  How is that incorporated in
           these to look for these things?
                       MR. T. HANLEY:  Well, I will go over --
                       DR. SIEBER:  Are do you just depend on the
                       MR. T. HANLEY:  No, this was a heads up to
           them, but it is incorporated into our start up testing
           programs.  So we will have a controlled look at all of
           those things as we are going up.
                       DR. SIEBER:  Now, your external nuclear
           instruments will all be --
                       MR. T. HANLEY:  We don't have ex-core.  We
           have all in-core.  
                       DR. SIEBER:  All in-core? 
                       MR. T. HANLEY:  That's correct. 
                       DR. SIEBER:  Okay.  Do they all work?
                       MR. T. HANLEY:  Most of the time.  We had
           some issues with copper migration in some of the SRMs
           and IRMs in this last refueling outage that we have
           replaced those that were susceptible.  So we have had
           good response with the nuclear instrumentation.
                       The simulator training began with a static
           walk through the similar was set up as full power EPU,
           and what they should see when they go in to take the
           unit for the first time, and at its new uprated
           condition, and just walk around and see where the
           different parameters are from where they are used to
           seeing it.
                       And just basically to get acquainted with
           the plant as you will be seeing it.  And we went
           through some normal operation scenarios; power
           changes, inserting rods, and doing some small recirc
                       And then did some dynamic scenarios that
           we selected to highlight both the differences that
           they will see at EPU and the similarities in their
           response under these conditions.
                       And we ran through a loss of feed water
           heating, and feed water controller failure, high
           recirc controller failure, condensate pump trip.  And
           obviously before a condensate pump trip, the first
           thing an operator does is verify the standby pump auto
                       Well, there is no standby pumps, and so
           now the new action is verify the recirc pumps are
           running back.
                       DR. SIEBER:  Right.
                       MR. T. HANLEY:  So we ran through a group
           one isolation and a loss of off-site power with a
           LOCA, and also a turbine trip without bypass with a
           ATWS.  Really from the operators experience the --
                       DR. SIEBER:  This is a turbine bypass.
                       MR. T. HANLEY:  That's correct.  So
           essentially it is almost the design basis ATWS,
           because you give no bypass applicability.  Really from
           the operator's feedback, they didn't see a lot of
           changes in their response to transients or accidents
           other than those specifically associated with hardware
           changes, like the condensate pump trip.
                       And that really is a credit to the generic
           EPGs now that we work with symptom-based emergency
           procedures.  You are going everything off a parameter.
                       So you are looking at TORUS temperature,
           and you are looking at drywell pressure, and you are
           taking actions at specific levels of those parameters
           before you reach them.  So it doesn't really affect
           how the operators respond.
                       DR. SIEBER:  Have you had to change your
           emergency response guidelines for the uprate?
                       MR. T. HANLEY:  Yes, there will be some
           minor changes to those.
                       DR. SIEBER:  Like control points, and sub-
           points, and things like that?
                       MR. T. HANLEY:  Right.  We are in fact 
           -- I believe that it is part of this submittal, and it
           may be a separate one.  We are changing our low level
           SCRAMs at that point from 8 inches to zero inches.  
                       So that obviously is an entry point into
           the EOP.  So that will be a change that goes in.  But
           the overall strategy of the Ops has not changed, and
           really the operators, their feedback was that they
           didn't see a significant difference in the way that
           they attack it as transient.
                       DR. SIEBER:  Has the power uprate created
           any walk arounds for the operator that otherwise would
           not exist?
                       MR. T. HANLEY:  We will only be able to
           tell that for sure once we get to those conditions. 
           As designed, operators are always skeptical, which is
                       But as a design, we should not have
           controllers left in manual that are supposed to be in
           automatic.  We should not have additional monitoring
           required once we get through our testing program.
                       DR. SIEBER:  That's right.  
                       MR. T. HANLEY:  And those are the things
           that we are on the lookout for, as designed, and none
           of those are built into this uprate.  
                       But those will be the things that we will
           have to look for when we get to the new license power
           condition to make sure that they are identified, and
           get put in our program, and get fixed in a timely
           basis.  So we don't intend to incur any operator work
           arounds to reach our new power, licensed power.
                       CHAIRMAN WALLIS:  Well, then all the
           modifications will be -- except for records update,
           will be complete, tested, and --
                       MR. T. HANLEY:  Well, digital feedwater,
           which is not being installed as part of EPU, but we
           are taking advantage of that for particular input into
           the recirc runback, obviously we will be doing start
           up testing as we start up from that.  So there will be
           testing that goes on with this.
                       DR. SIEBER:  So the run back won't occur
           until you put that in?
                       MR. T. HANLEY:  No, it will.  It will all
           be in during the outage, but all the testing on that
           now won't be complete you are at power, and that is
           the only way to test it.
                       But our intention is not to have feed
           water heat level control valves left in manual, or
           have the emergency dumps on those bias partially open. 
           So those are the things that the operators are
           concerned about.
                       And we have done a lot of analysis, and
           the increased shell pressure should increase the flow
           through the same sized valves.  So we shouldn't have
           an issue with the drains on the feedwater heaters.
                       DR. SIEBER:  And you will find that out
                       MR. T. HANLEY:  Probably, and that's --
           well, as operations, we are keeping our eyes out for
           anything that didn't come out the way that we were
           told it was going to.
                       That really covers the training portion of
           it, and so I was going to go on to the testing.  The
           way that we are going to perform our testing is do one
           power increase a day, and approximately 3 percent, and
           stop there, and collect all of our data, and compare
           it to the predicted value acceptance criteria.
                       And look for anything that would keep us
           from increasing power the next day, and if we have to
           make minor system adjustments, and if we have to go
           back and reevaluate, and if we have to go back and
           hold power there, that's the point where we will do
                       We will be increasing along a constant
           flow control line to limit the variables that we are
           changing at one time.  So, really essentially we will
           be increasing recirc pump speed over the days to
           increase power.
                       We are going to start collecting our
           steady state day at 90 percent of our current licensed
           thermal power for the systems that we are monitoring
           for vibration data for the main steam and feed lines.
                       And we will actually be getting that data
           at 50 percent of our current license thermal power. 
           But for the systems, we have got good operating
           history, and we just want to get a base line at 90
           percent of our current license power level.
                       DR. SIEBER:  Are you going to do anything
           special with the turbine since you are getting a new
           high pressure turbine?
                       MR. T. HANLEY:  And we are changing the
           diaphragms on the control valves, and what we will be
           doing is we always monitor turbine vibrations, and we
           always do -- 
                       DR. SIEBER:  And that is standard on the
           start up?
                       MR. T. HANLEY:  Right, and we will be
           doing our normal control valve stroking to ensure that
           the other control valves can compensate adequately for
           one control valve closing.
                       But the high pressure turbine itself will
           have a unique MOD test associated with it, and not
           related to EPU.  In fact, Dresden right now is
           installing a new high pressure turbine.
                       And so when they start up, even though
           they won't be licensed EPU, they will be doing their
           generic MOD test for that.
                       DR. SIEBER:  Now, you have a boreless
                       MR. HAEGER:  Boreless rotor? 
                       DR. SIEBER:  Yes.  Well, a spindle.  We
           always run a line through the bore, and if you don't
           have a bore, then I am not sure how you align.
                       MR. HAEGER:  The question, George, is if
           you don't have a bore, how do you do the alignment?
                       MR. NELSON:  This is George Nelson.  They
           are using laser alignment techniques, which are
           primarily off of the opening of the shaft.
                       DR. SIEBER:  And we shoot through the
           shaft with a laser.
                       MR. T. HANLEY:  And these tests will be
           conducted with a dedicated testing team lead by an
           SRO.  There is one assigned to Quad Cities and one
           assigned to Dresden.  We are also sending our people
           to Dresden for our start up testing when they begin
           their power ascension testing.
                       And then those people from Dresden will
           becoming to Quad to make sure that we capture any
           lessons learned about that.  We are doing specific
           signal and system response testing for the two
           systems, control systems, that are being significantly
           altered for EPU.
                       The pressure control system for the main
           turbine, the control valves will actually control
           turbine throttle pressure at a lower pressure than it
           does right now to maintain reactor pressure at a
           thousand-five, because it is controlling at a new set
           point, and we will be doing specific pressure
           incremental changes on it to make sure that it has a
           stable response.
                       And that it does not oscillate
           divergently, and we are also going to do a pressure
           regulator fail over test to make sure that the back up
           pressure regulator takes control when it is supposed
           to, approximately three pounds higher than the normal
           pressure regulator.
                       The feed water level control system, we
           operate normally in three element control, and so the
           input is from feedwater and steam flow have been
                       We are going to do some specific testing
           of that unrelated to our digital feedwater at Quad
           Cities and Dresden, which went digital a number of
           years ago.  
                       And doing incremental level changes and
           verify the system response as stable.  We will put one
           feed rate valve in manual and make adjustments to it,
           and verify that the other valve can control
                       And then we will do that at varying power
           levels to ensure that it is stable over the range of
           normal operation for them.  We will be doing specific
           system equipment performance monitoring.
                       These are mainly geared towards the
           balanced plant systems, which are the ones being
           modified for EU.  Each parameter we have gotten from
           the system engineers are predetermined acceptance
                       And the performance parameters, as we go
           up through our 3 percent increases each day, that is
           where we will be collecting the data, and comparing
           that, and seeing if any changes need to be made to the
           plan, and to the system operation before we continue
           our increase.
                       In addition, there are the 10 balance of
           plant systems that we have selected, and we will also
           be monitoring the recirc pumps since we will be
           operating those at a higher RPM than we are currently
           and also the reactor, and just verifying that we don't
           see anything odd happening there.
                       Specifically, we are increasing the flow
           in the feed water and steam -- main steam line piping,
           and want to verify that we don't have excessive
           vibration and it is difficult to try to determine
           ahead of time where that may occur.
                       And so we are putting vibration monitoring
           equipment, both inside and outside containment.  We
           will be getting lower power vibration data, which I
           talked about earlier, and we are getting about 50
           percent power.  
                       And then the acceptance criteria are
           established from the ASME stress analysis limits on
           what is acceptable and what is not.  And we won't
           exceed any of those limits.
                       In conclusion, we have completed at
           Dresden extensive training, and we will complete at
           Quad Cities extensive training for the operators,
           which has used both the design features and are
           operating and experience from other plants, the
           testing plans, incremental and comprehensive, and
           gives us good guidance before we increase power to the
           next level.
                       And the project implementation will ensure
           that EPU is implemented as designed.  Do you have any
           questions?  If not, with that, I will turn it over to
           Jeff Benjamin, Vice President of Licensing and
           Regulatory Affairs. 
                       MR. BENJAMIN:  Since I am on the verge of
           having to say good evening, I will make my remarks
           brief.  First of all, we are pleased to have the
           opportunity this afternoon to present our submittal.
                       As I think we articulated at the beginning
           of this presentation, our objective at the outset of
           this project was to increase the power output for the
           Dresden and Quad Cities stations, while maintaining
           the appropriate operating margins, and continuing to
           operate the units safely and reliably.
                       I think the project team that has worked
           for the past two years in partnership with our
           vendors, have met those objectives as we talked about
           today, and as supported by the bullets up on the
           slide, I think our package before the Commission for
           their review and approval also reflects those points.
                       I want to particularly emphasize what Tim
           touched on last, and that is that we have had the
           opportunity to go through three power uprates in our
           fleet over the past couple of years, and have learned
           through each one of those the importance of our change
           management program, including the operator training,
           testing program, and the monitoring program.
                       And I am confident that the infusion of
           those lessons learned, as you just heard Tim
           articulate a piece of.  We will also add confidence
           that the assumptions that went into the power uprate
           package will be borne out and tested out appropriately
           as we bring the unit up on line, and as we test it out
           at the higher power levels.
                       So, in summary, we believe that the
           submittal that we have before the staff demonstrates
           the acceptability of our proposed power uprate, and
           that completes our presentation, subject to any
                       CHAIRMAN WALLIS:  Thank you very much.  Do
           we have any questions from the committee or
                       Now, you are going to make a presentation
           to the full committee, and you are going to compress
           this presentation by a factor of eight or something
           like that?
                       MR. HAEGER:  Yes, and we would expect some
           guidance from you on that.
                       MR. BENJAMIN:  I think we would anticipate
           working with you on the areas of emphasis that you
           would like to see, and obviously we would compress
           that material accordingly to facilitate the discussion
           within your schedule constraints.
                       CHAIRMAN WALLIS:  I think things that you
           can show in a diagram would be helpful; like with
           numbers with the containment analysis and the
           conclusions from the ECCS and so on, and show that you
           met some criteria specifically.
                       CHAIRMAN WALLIS:  Okay.
                       MR. BENJAMIN:  I also assume that you
           would look for a condensed version of our risk
                       CHAIRMAN WALLIS:  I would think we would
           need that, yes.  We need a very brief overview to
           remind the committee of what is involved with this
           EPU, in terms of changes in flow rates and so on.
                       MR. BENJAMIN:  We will clearly articulate
           differences between Dresden and Quad Cities as well in
           the presentations.  So we won't have to go over that
                       DR. SCHROCK:  I would think it would save
                       MR. BENJAMIN:  I think it will, yes.
                       DR. KRESS:  I think you want to talk about
           your reasons for doing the transient test, because
           that will be a question of contention perhaps.
                       MR. BENJAMIN:  Very good.
                       CHAIRMAN WALLIS:  Do we need anything on
                       MR. BENJAMIN:  I had a chance to observe
           the Duane Arnold presentation, and we may have an
           opportunity with the full committee to go back over
           the power to flow chart one more time, and have a
           chance to articulate exactly how we operate in the
           higher power regions.
                       And in a very practical way I think show
           how we do that, and --  
                       CHAIRMAN WALLIS:  This is part of the
                       MR. BENJAMIN:  This would be part of an
           overview, and I would suggest that Tim could go back
           through that again with the full committee and do that
           rather efficiently.  And I think that would be
           worthwhile as well.
                       DR. FORD:  As part of the materials
           degradation is concerned, I guess one bullet.
                       MR. BENJAMIN:  No problem.
                       DR. FORD:  I don't know if I am allowed to
           say anything.  Am I?
                       DR. KRESS:  Yes, you can say or talk about
           things like that.
                       CHAIRMAN WALLIS:  Yes, you can.
                       DR. FORD:  Well, I don't see any problems
           at all with that.
                       DR. KRESS:  Well, it seems like they might
           want to discuss the FAC, because that is what will
           come up at the full committee.
                       DR. FORD:  There is a whole range of
           things, such as the FAC, the flow induced vibration,
           and potential cracking of the core shroud.  It seems
           to me that all of those issues were in fact being
           adequately managed.  We all recognize that they are
           being adequately managed.  
                       DR. KRESS:  And I think that the committee
           would probably have a preconceived notion that
           extended power uprates only affects FAC.
                       MR. BENJAMIN:  So could I suggest that we
           would have one slide that would cover that topic, and
           that would have the bounds around how we are managing
           our materials and draw those conclusions?
                       DR. FORD:  Well, depending on what we hear
           from the staff, and they don't have any problems with
                       CHAIRMAN WALLIS:  And for accuracy, you
           could have a summary slide for ATWS.
                       DR. SCHROCK:  One thing that never came up
           in this meeting that I wondered about and that is the
           statement in the SERs that the task code has not had
           prior NRC approval, but it is under review.
                       MR. HAEGER:  Dan, can you speak to that?
                       DR. SCHROCK:  That ought to get clarified
           I would think.
                       MR. PAPPONE:  This is Dan Pappone.  The
           task code has been accepted for transient evaluations,
           and delta-CPR evaluations, and it is currently under
           review for the LOCA considerations, where we are using
           it and taking it one step further.
                       As far as transients, we are looking at
           whether or not when or if transition occurs, and in
           LOCA we are looking at when and where.  But that is
           under review.
                       DR. SCHROCK:  When I look at this table of
           computer codes used for EPU, for transient analysis,
           and ATWS, you have a number of codes, and it appears
           in both places.
                       MR. PAPPONE:  Right. 
                       DR. SCHROCK:  It is a little hard to tell
           -- and also I think it is G.E. terminology.  You have
           SAFER/GESTR, which is a cover name for amalgamations
           of these various codes; is that right?
                       MR. PAPPONE:  That's right.  
                       DR. SCHROCK:  And I may be alone in not
           understanding how they go together to do what you are
           doing it with it, but maybe that is something that
           needs to be clarified.
                       DR. KRESS:  It certainly would be nice to
           see that database that you referred to on the ODYN
           code that shows that you are still within the
           parameters that it has been validated at.
                       MR. BENJAMIN:  Would you like us to submit
           that prior to the full committee, or would you like us
           to submit that at the committee?
                       DR. KRESS:  At the full committee would be
                       MR. BENJAMIN:  Okay.  That's fine.
                       CHAIRMAN WALLIS:  On the piping and
           reactor internals, I don't think you need to spend
           very much time.  I think you do have to address the
           fluence issue, because they expect it to go up and it
           went down, or it appeared to go down.  
                       DR. FORD:  I think that comes under
           materials degradation.
                       CHAIRMAN WALLIS:  Well, we don't need to
           go into a lot of the --
                       MR. BENJAMIN:  That would be an
           approximately one slide treatment as you suggested,
           yes, and we would pick that up in there.
                       CHAIRMAN WALLIS:  If there is nothing
           else, we will recess until tomorrow at 8:30 a.m., and
           we will then hear from the staff.
                       (Whereupon, the meeting was adjourned at
           5:38 p.m, to convene at 8:30 a.m. on Friday, October
           26, 2001.)


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